ORIGINAL ARTICLE Reduction Mammoplasty: The Experience In Ile
MS Id sto. H333/67531/metadc...American women underwent augmentation or reconstructive mammoplasty...
Transcript of MS Id sto. H333/67531/metadc...American women underwent augmentation or reconstructive mammoplasty...
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MS Id sto. H333
NEUROPSYCHOLOGICAL DEFICITS ASSOCIATED WITH
SILICONE GEL BREAST IMPLANTS
DISSERTATION
Presented to the Graduate Council of the
University of North Texas in Partial
Fulfillment of the Requirements
For the Degree of
DOCTOR OF PHILOSOPHY
By
Mary E. Kasper, B.A., M.A.
Denton, Texas
August, 1996
37*?
MS Id sto. H333
NEUROPSYCHOLOGICAL DEFICITS ASSOCIATED WITH
SILICONE GEL BREAST IMPLANTS
DISSERTATION
Presented to the Graduate Council of the
University of North Texas in Partial
Fulfillment of the Requirements
For the Degree of
DOCTOR OF PHILOSOPHY
By
Mary E. Kasper, B.A., M.A.
Denton, Texas
August, 1996
t-iV-
Kasper, Mary E. Neuropsychological Deficits Associated
with Silicone Gel Breast Implants. Doctor of Philosophy
(Clinical Psychology), August, 1996, 70 pp., 6 tables,
references, 64 titles.
Thirty-two silicone breast implant patients scored in
the mild to moderate range of impairment on the Halstead-
Reitan Neuropsychological Battery. An unusual number of
patients had positive tests for antinuclear antibody on
immunological testing and a high incidence of EEG
abnormalities were found. Personality testing revealed an
MMPI profile which is typical for neuropsychological^
impaired subjects but components were consistent with
extreme emotional distress. None of the subjects were near
the cutoff score for malingering or faking bad on the F-K
index of the MMPI. There was no apparent relationship
between length of exposure and the severity of neurological
impairment. Also, explanted subjects performance was not
improved when compared to subjects whose implants were still
in place.
TABLE OF CONTENTS
Page
LIST OF TABLES iv
Chapter
I. INTRODUCTION 1
Silicone and its Medical Uses Silicone and Autoimmune Disorders Why Silicone Breast Implants are Thought to
be Harmful Complications Associated with Silicone Breast
Implants Importance of Study
II. METHOD 21
Subjects Materials Procedure
III. RESULTS 28
Description of Sample Neuropsychological Test Scores of Silicone
Implant Patients Versus Published Cutoff Scores
Comparison of Silicone Breast Implant Group to Published Scores from SLE Patients
Length of Exposure to Silicone Implants and Neuropsychological Deficits
Patients with Silicone Implants Versus Patients who have had Their Implants Removed
Patients with Documented Rupture Versus Patients with Documented Intact Implants
IV. DISCUSSION 39
Limitations of Study Research Directions
APPENDICES 50
REFERENCES 62
111
LIST OF TABLES
Table Page
1. Mean WAIS-R IQ Values for Silicone Breast Implant Patients 56
2. Means of Silicone Implant Patients on the Most Sensitive Components of the HRNB 57
3. Mean Personality Test Scores of Silicone Breast Implant Patients 58
4. Silicone Implant Patients' HRNB Performance Versus Cutoff Scores Used to Determine Brain Damage 59
5. Silicone Implant Patients Performance Versus Three Groups of Systemic Lupus Eretymatosus Patients' Performance on Trails A and B and Finger Tapping Tests 60
6. Silicone Implant Patients Performance Versus Three Groups of Systemic Lupus Eretymatosus Patients' Performance on the WAIS-R 69
IV
CHAPTER I
INTRODUCTION
From 1962 to the early 1990's, 300,000 to two million
American women underwent augmentation or reconstructive
mammoplasty and were implanted with silicone breast
prostheses (Smith, 1993). Despite the large number of
silicone implants, the long term effects of silicone
implants were unknown. Due to the laws applicable to
medical devices, implant manufacturers were not required to
show that the devices were safe and effective.
Silicone breast implants were unregulated until 1976,
when the Medical Device Amendments to the Food, Drug and
Cosmetic Act (21 U.S.C.A. S 360 et seq; West 1976) gave the
FDA the authority to regulate all medical devices. However,
the 1976 act only required devices classified as high risk
(Class III) to be proved safe and effective. The FDA did
not classify silicone breast implants as Class III devices
until 1988, and it was not until 1991 that the FDA required
manufacturers to submit premarket approval (PMA) or proof of
the product's safety and effectiveness (Rohrich & Clark,
1993). The FDA advisory panel met to evaluate data
presented by seven breast implant manufacturers, and the
following year concluded that there was insufficient
evidence to prove implants were safe and effective.
Consequently, in 1991 the FDA imposed restrictions on the
use of silicone implants (Human Resources and
Intergovernmental Subcommittee of the Committee on
Government Operations, 1993). As a result of the FDA's long
inaction, a large number of women received silicone breast
implants, a product with long term sequelae that are not yet
fully understood.
Silicone and its Medical Uses
Silicone is a general term that refers to a generic
class of materials that are composed of polymer chains of
alternating silicon and oxygen atoms. The viscosity of
silicone is determined by the average length of the chains
(Kossovsky & Heggers, 1987). Many types of medical implants
are pure silicone, silicone encased, or silicone treated.
Examples of other silicone based medical products include
silicone encased pacemakers, silicone clips used in tubal
ligations, silicone hydrocephalus shunts, and silicone joint
prostheses (Englert, Howe, Penny & Brooks, 1994). Some
physicians believe that silicone is a biologically inert
material, as evidenced by its many successful uses (Giltay,
Moens, Riley, & Tan, 1994). Others believe that silicone
has a high degree of biocompatibility, but is not a
biologically inert substance (Spiera, Gibofsky & Spiera,
1994). The many failures of implants associated with
periprosthetic fibrosis, lymphadenopathy, silicone
migration, and silicone fragmentation are believed to be
related to silicone bioreactivity (Heggers, Kossovsky,
Parsons, Robson, Pelley, & Raine, 1983; Kossovsky & Heggers,
1987). These authors believe that some individuals may be
predisposed to silicone hypersensitivity, which involves an
immunological reaction to silicone. The hypothesis that
some individuals are silicone hypersensitive would be
consistent with the fact that not all breast implant
patients appear to develop complications.
Silicone and Autoimmune Disorders
Many of the common complications currently thought to
be associated with silicone breast implants are autoimmune
disorders. To clarify how silicone relates to autoimmune
disorders, a brief explanation of the immune system follows.
The immune system is composed of white blood cells that
function to protect the body against toxins (bacteria,
viruses, foreign substances, etc.). Macrophages are
important immune cells which ingest, kill, and digest
foreign substances, and send messages that mobilize other
immune cells. Antibodies are substances that bind to the
foreign substance and help identify it for attack by other
immune cells, and differentiate the foreign substance from
body tissue. The immune system is able to effectively
differentiate the foreign substance from body tissues until
the amount of the foreign substance surpasses a critical
level. At this point, the immune system becomes
overwhelmed, and works as hard as it can in an attempt to
rid the body of the toxins. In these circumstances, the
immune system may become confused and attack various body
tissues. This immune system overload may only affect one
part of the body, or may affect the entire body. Autoimmune
disorders can affect the central nervous system (CNS),
although the exact mechanism of pathogenesis is not known.
Some researchers have proposed that the autoimmune disorder
can affect the brain through vasculitis and/or antibodies
against nervous system tissue (Bluestein, 1984; Denburg &
Temesvari, 1983). This type of immune system dysfunction is
hypothesized to happen in silicone breast implant patients
as a result of chronic silicone exposure (Vasey & Feldstein,
1993; Lewy, 1994).
Why Silicone Breast Implants are Thought to be Harmful
There are two main reasons why silicone gel breast
implants are thought to be more likely to cause immunologic
problems than other types of silicone implants. The first
is that all silicone breast prostheses release some of their
gel content into the patient's system, where it can then
migrate. Most other types of implants are made of hard
silicone, which is less likely to migrate, and is much
easier to remove in the case of complications (Vasey &
Feldstein, 199 3). The most common type of breast implant is
similar to the prototype model developed in the 1960's,
which consists of a silicone rubber envelope or shell that
is filled with silicone gel (Sanger, Kolachalam, Komorowski,
Yousif, & Matloub, 1992). In some cases the silicone shell
ruptures, releasing silicone gel into the patient's system.
Estimates of implant rupture range from 4% (Atwood et. al,
1994) to 16% (Nelson^ 1981). Many times implant ruptures
are "silent" and go undetected until the patient has surgery
for implant exchange or a mammogram (Rohrich & Clark, 1993).
Fifty seven patients out of a sample of 96 who underwent
implant removal due to complications were found to have
ruptured implants (Shoaib, Patten, & Calkins, 1994).
Ruptured implants are commonly seen by plastic surgeons
during implant revision surgery, and some believe that
"ruptured implants are often not detectable, asymptomatic,
and not likely to cause problems" (Berger & Bostwick, 1995).
Silicone gel is also able to migrate into the patients'
system through an intact envelope. In a study of tissue
samples from 41 women undergoing implant revision surgery,
free silicone resulting from gel bleed was found in 70% of
the patients. While the authors did not observe free
silicone in the remaining 30% of the cases, they believe
that silicone escaped from the envelope in each instance, as
they found evidence of empty holes and cysts in surrounding
breast tissue representing silicone damage in every patient
(Kasper & Chandler, 1994). Other sources agree that all
breast implants leak silicone gel through the hard silicone
envelope (Atwood et al., 1994).
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The second hypothesis, related to why silicone gel
implants are associated with problems to a greater degree
than other types of silicone implants, is related to their
placement in the body. The location of the implant makes it
likely that the silicone that escapes from the implant will
drain into the lymphatic system, which makes an immunologic
response more likely (Kossovsky & Heggers, 1987).
The silicone gel that escapes from the implant shell is
a major area of concern. However, some researchers believe
that the nature of the silicone envelope may be contributing
to the autoimmune problems experienced by many silicone
implant patients. The silicone shell of the implant is
recognized as a foreign substance by the immune system. The
immune system sends macrophages to attack the implant shell
and causes microscopic pieces of silicone to be shed into
surrounding tissues. This process is known as shell
erosion. Shell erosion is thought to be due to the
composition of the shell, as it has been observed in saline
filled implants as well as in silicone gel filled implants
(Vasey & Feldstein, 1993).
In review, it appears that the majority of breast
implant recipients will have gel outside the prosthesis
envelope either through rupture or gel bleed, as well as
exposure to microscopic pieces of silicone due to shell
erosion. The location of the implant may also facilitate
drainage into the lymphatic channels of the upper body.
Some implant patients may be predisposed to silicone
hypersensitivity, and gradually develop an immunologic
reaction, and subsequent rheumatic and CNS complications.
Complications Associated With Silicone Breast Implants
Although all physicians do not agree on what types of
complications are associated with silicone breast implants,
the most commonly listed major health concerns include:
capsular contracture, a possibility of increased cancer
risk, delayed mammographic detection of breast tumors, and
implant rupture or gel migration, contributing to the
development of autoimmune disorders and subsequent CNS
deficits (Rohrich & Clark, 1993). Capsular contracture is a
condition that can occur after implantation, when the
fibrous capsule surrounding the implant becomes hard,
uncomfortable, and sometimes deforms the breast (Brautbuar,
Vojdani, & Campbell, 1994).
Researchers are not in agreement as to the risk of
cancer associated with gel implants, and the implications
silicone implants have for mammography (Rohrick & Clark,
1993). In a study involving 68 breast augmentation
patients, a 3 0% decrease was noted in the area of breast
tissue visualized by standard compression mammography
(Handel, Silverstein, Gamagami, Jensen, & Collins, 1992).
Eklund, Busby, Miller and Job (1988) developed a modified
mammography procedure for breast implant patients designed
to increase the amount of breast tissue visualized. The
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Eklund mammography technique has been shown to be
ineffective in increasing the amount of tissue visualized in
patients with moderate or severe capsular contracture
(Handel et al., 1992). Some mammography units do not
utilize the Eklund technique with implant patients, because
of the possibility of implant rupture during the procedure
(Bantick & Taggart, 1995). The health concerns that are
most salient to this investigation of central nervous system
deficits are the risks of implant rupture, gel migration and
the resulting risk of autoimmune disorders.
At the present time, there is no definitive
epidemiologic data that establishes a link between silicone
gel breast implants and autoimmune diseases (Bridges &
Vasey, 1993). Some believe that the connection between
silicone breast implants and autoimmune disorders may be
coincidental, as this type of disorder is most common in
young thin women, and young thin women are the typical
implant recipients (Atwood et. al, 1994). A commonly cited
retrospective study involving a record review of 749 women
failed to find an association between rheumatoid arthritis,
SLE, Sjoren's Syndrome, dermatomyositis, polymyositis,
systemic sclerosis, ankylosing spondylitis, psoriatic
arthritis, polymyalgia rheumatica, vasculitis, arthritis
associated with inflammatory bowel disease, polychondritis,
Hashimoto's thyroiditis, primary biliary cirrhosis,
sarcoidosis, and cancer other than breast cancer (Gabriel,
O'Fallon, Kurland, Beard, Woods, & Melton, 1994). While
this study was well designed, the sample had been exposed to
implants for a relatively short time (M = 7.8 years
exposure), and diagnoses of atypical Lupus or atypical
Multiple Sclerosis were not included, both of which are
common diagnoses for silicone breast implant patients.
There are many studies that suggest a relationship
nonetheless. Typical signs of autoimmune disorders include:
pain and swelling of joints, tightness, redness or swelling
of the skin, swollen glands or lymph nodes, unusual and
unexplained fatigue, swelling of the hands and feet, and
hair loss (U.S. Food and Drug Administration, 1994). The
group of specific neurologic and autoimmune diseases are
referred to as human adjuvant diseases. This group of
disorders associated with silicone gel implants includes:
systemic lupus erythematosus (SLE), scleroderma,
polymyositis, rheumatoid arthritis, mixed connective tissue
disease, Sjogren's syndrome, fibrositis, carcoidosis,
atypical neurologic diseases such as atypical Lupus and
atypical Multiple Sclerosis, and myositis (Spiera, Gibofsky,
& Spiera, 1994), as well as silicone adjuvant disease (Lewy,
1994) .
Silicone implants and Systemic Lupus Erythematosus.
SLE is defined as "a chronic inflammatory disease of
connective tissue that causes injury to the skin, joints,
kidneys, nervous system, and mucous membranes" (Taber, 1993,
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p. 1139). SLE is one of the more serious of the autoimmune
diseases listed above, and is the autoimmune disorder most
commonly associated with central nervous system involvement.
The central nervous system is estimated to be compromised in
30 to 75% of patients with SLE (Carbotte, Denburg, Denberg,
Nahmias, & Garnett, 1992; Kushner et al., 1987).
SLE with nervous system involvement is often referred
to as Neuropsychiatric SLE (NP-SLE). There is currently no
consistent diagnostic clinical criteria for NP-SLE (Kassan,
& Lockshin, 1979). Neuropsychological testing of SLE
patients, and NP-SLE patients showed cognitive impairment to
be present in 66% of a sample of NP-SLE patients, and in
almost half of SLE patients in which there previously was no
suspected CNS involvement (Denberg, Carbotte, & Denberg,
1987). It appears that although the term NP-SLE is in use,
it is currently of questionable usefulness in discriminating
SLE with CNS impairment from SLE without CNS impairment.
Neuropsychological testing is thought to be the most
sensitive method to evaluate CNS involvement in SLE, and has
been shown to be more useful than Magnetic Resonance Imaging
(MRI), Computerized Tomography (CT) etc. (Carbotte, Denburg,
Nahmias, & Garnett, 1992; Mondrego, Venegas, Cuenca, Moreno,
& Delgado, 1994)
Denburg, Carbotte & Denburg (1987) administered a
complex battery of standard neuropsychological tests to 86
women diagnosed with SLE. SLE patients with suspected CNS
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involvement (NP-SLE) showed a pattern of neuropsychological
test results that the authors believe is reflective of
diffuse or multifocal CNS dysfunction. Results showed this
group to differ significantly from a control group on verbal
and nonverbal measures of memory, Reasoning and fluency
(speed).
Silicone svmptomotolav may comprise a distinct
disorder. Current research suggests that the autoimmune
symptoms associated with silicone breast implants (SBI) that
are sometimes diagnosed as SLE or other connective tissue
disorders may in fact be a unique syndrome composed of
diverse symptomatology (Solomon, 1994). The silicone
syndrome was first identified in 1964 and labeled Adjuvant
Breast Disease (Miyoshi et al.). An adjuvant is a substance
that changes or enhances immune system functioning. An
entire sample of 100 consecutive cases of silicone exposed
patients presented with a variety of neurological,
rheumatological and nonspecific symptoms that differed
markedly from idiopathic rheumatological or neurological
disorders (Shoaib, Patten, & Calkins, 1994).
Common symptoms include: weakness, fatigue, myalgia,
morning stiffness, arthralgia, short term memory loss,
sensory loss, headache, dry eyes and mouth (Solomon, 1994).
Patients with adjuvant breast disease typically have at
least 20 complaints and commonly endorse over 50% of the
common disease symptoms (Patten, & Shoaib, in press). A
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list of common symptoms is contained in the Information
Sheet: Breast Implant Cases (Krusz, 1994) in Appendix A.
Lappe (1993) also believes that silicone related
symptoms represent a distinct syndrome. He refers to this
syndrome as "silicone reactive disorder" (p. 348), based on
findings that the most seriously ill patients in his study
showed antibody patterns that were uncharacteristic of other
disorders, and the fact that the disorder associated with
silicone appears to be partially reversible. Approximately
7 0% of patients experience a lessening of their rheumatic
symptoms within two years after removal of their implants
(Patten & Shoaib, 1995; Vasey & Feldstein, 1993). Most
classic autoimmune disorders do not show this pattern of
revers ib i1ity.
Lewy (1994) also believes that there is a unique
syndrome associated with silicone breast implants. He
refers to the syndrome as Silicone Human Adjuvant Disease
(SHAD), "a multisystem disorder with a unique combination of
impaired higher neurological functions, neuropathic
symptoms, arthralgias, and constitutional symptoms
associated with multiple autoantibodies and easily found
abnormalities on imaging" (p. 1). Forty-seven percent of
230 implant patients showed areas of demyelination,
infarction or vasculitis on brain MRI (Lewy, 1993). Lewy
describes a typical SHAD patient's symptoms as: burning
chest and shoulder, breast tenderness and pain, insomnia,
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difficulty breathing, palpitations, rapidly worsening short
term memory loss, confusion, presence of at least one
autoantibody on lupus panel testing, and prolific basic
protein antibody production.
Rheumatologists at the University of South Florida
Medical School have also observed a common group of symptoms
in silicone implant patients who develop problems. This
syndrome, referred to as silicone disease, consists of the
following six symptoms: chronic fatigue, inflammation and
muscle pain, joint pain and swelling, swollen lymph nodes in
chest, neck underarms and groin, low grade fever (100 to 101
degrees), and gastrointestinal symptoms including cramping
and abdominal pain. Other common symptoms include:
burning/crawling sensations indicative of peripheral nerve
problems, night sweats, memory loss, dry eyes and mouth,
headache, rashes, difficulty swallowing, bladder problems,
sinus irritation, numbness or altered sensation in the body,
skin tightening, lung problems, decreased sex drive, and
depression. Silicone breast implant patients presenting at
the University of South Florida Medical School often show
constellations of these symptoms, plus a borderline positive
antinuclear antibody test, and the absence of a "butterfly"
facial rash, or kidney disease. The absence of a butterfly
rash and kidney disease is significant as these symptoms
would suggest that the patient is suffering from true SLE
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rather than atypical lupus due to silicone toxicity (Vasey &
Feldman, 1993).
The theory that silicone toxicity may result in an
atypical disease has been met with criticism by some who
believe that this syndrome is a fabrication of unscrupulous
plaintiff attorneys (Bernstein, 1995). Bernstein states
that this theory was invented because, as there is no clear
definition of an "atypical" disease, it is impossible to
engineer an epidemiological study to determine the existence
or causes of this type of disorder. On the surface this
argument may appear plausible to some, however there is
enough medical evidence to explore the theory that some
silicone implant patients may be suffering from a spectrum
of immune disorders.
Based on clinical observation of approximately 30
individual silicone breast implant patients, a Dallas
neurologist observed commonalities within the group. The
constellation of symptoms noted include; subtle EEG
abnormalities indicative of cortical irritability especially
in the posterior frontal and temporal lobes; confusion,
short term memory loss, and peripheral neuropathy (J. C.
Krusz, personal communication, October, 1994).
The above mentioned observations are consistent with a
recent study which found significant QEEG abnormalities on
100% of the first 23 silicone breast implant patients being
evaluated for neurocognitive symptoms (Hoffman, Stockdale,
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Hicks, & Schwaninger, in press). These authors found memory
related symptoms to be the most prevalent patient complaint
in this group, and the most common QEEG abnormalities to be
in the temporal region.
After examination of approximately 20 silicone breast
implant patients, a Dallas neuropsychologist believes that
there may be a distinct pattern of neuropsychological
deficits associated with silicone breast implants. After
observing these cases, clinical impressions are that these
patients tend to show impairment on the following portions
of the Halstead-Reitan Neuropsychological Battery: Category
test, Tactile Form Recognition, Tactual Performance Test
Total Time and Localization score, as well as mildly
depressed scores on the Finger Oscillation Test, and mild
deficits on the Digit Symbol subtest of the Wechsler Adult
Intelligence Scale-Revised (W. B. Jones, personal
communication, November 15, 1994).
Examination of central nervous system deficits in
silicone breast implant patients. Upon analysis, it appears
that many medical professionals believe that some type of
chronic, progressive autoimmune disorder is associated with
SBI's. Many believe that silicone toxicity leads to an
atypical neurologic disorder that shares common symptoms
with SLE as well as other autoimmune disorders like Multiple
Sclerosis.
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There is a general consensus that CNS involvement is
present in a large proportion of patients with SLE, and that
neurological and neuropsychological testing is an
appropriate way to investigate and document these deficits.
As silicone associated syndrome is' an atypical neurological
disease similar to SLE, neurological and neuropsychological
testing is an appropriate way to investigate CNS deficits in
this population as well.
While no studies of this type have yet been published,
a similar study of 15 women revealed interesting findings.
This small scale investigation found common abnormalities on
SPECT scans, especially statistically significant bilateral
temporal decreases. These authors also found that the
implant patients had significantly below average
performances on the verbal learning, short and long delayed
free recall, and delayed recognition portions of the
California Verbal Learning Test. However, their sample
showed average performance on measures of attention,
language and intelligence (Brown, Patten, Cooke, Shoaib, &
Jhingran, in press).
The purpose of the present study was to investigate a
possible association between neuropsychological deficits on
standard neuropsychological tests, neurological testing
(Quantitative Electroencephalogram), and autoimmune
symptomology in SBI patients. While this study will
primarily investigate central nervous system deficits
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associated with silicone breast implants, autoimmune data
will be included in an effort to make findings useful to a
wider range of health care professionals.
Five main research questions were investigated in this
study. The first level of analysis attempted to
differentiate silicone breast implant patients from normal
controls (using published norms) on neuropsychological,
neurological (QEEG, SPECT scan), and immunological measures.
A priori, the silicone implant group was expected to
significantly differ from normal controls on the following
scores; the Halstead-Reitan Impairment Index, and the Global
Neuropsychological Deficit Score (GNDS). The Impairment
Index and the GNDS are general indicators of
neuropsychological impairment. Exploratory analysis was run
on the remainder of the test scores, with special focus on;
Category Test, Tactual Performance Test Localization Score,
Tactile Performance Test Total Time, Finger Oscillation
Test, and the Digit Symbol subtest of the WAIS-R.
The second level of analysis attempted to determine if
SBI patients are significantly different from SLE patients
on neuropsychological measures using the norms for women
with SLE with suspected CNS involvement published in
Denberg, Carbotte and Denberg's 1987 study. A priori the
silicone implant group was expected to be different from the
SLE group norms on measures of cognitive speed. Exploratory
analyses was run on the remainder of the test scores.
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The third level of analysis attempted to determine
whether there is a typical neuropsychological profile
associated with patients who have or have had silicone
breast implants. The fourth research question examined
length of exposure to silicone implants and
neuropsychological deficits to determine if there is a
relationship. Finally we attempted to determine if patients
who have had their implants removed are significantly
different on test data than patients who still have their
implants.
Importance of Study
Currently the Brown et al. (in press) study stands
alone in addressing the neuropsychological deficits
associated with silicone gel breast implants. Since the
1992 FDA ruling that limited silicone breast implants to
controlled trials, there have been a large number of
articles speculating on possible side effects. The majority
of these articles address the rheumatic symptoms thought to
be associated with the implants, have small sample sizes,
and are composed of patients who have been exposed to
implants for less than 10 years. Some physicians have noted
irregularities in brain scans, confusion, and short term
memory loss in a significant number of their silicone breast
implant patients. However, it is not yet clear if there is
a common constellation of neuropsychological deficits
associated with the implants.
1 9
This project began to research the relationship between
neuroimmunologic symptoms and neuropsychological deficits.
Results from this initial study add to the existing data on
the long term effects of silicone breast implants, and give
direction to future researchers in the area.
It is important that the relationship between central
nervous system deficits and silicone implants be
investigated for several reasons. Probably the most
significant reason is to be able to have more data on
silicone implants available to women with silicone breast
implants and professionals treating them. With more data,
better informed decisions could be made about treatment.
Women with silicone implants who suffer from some of the
associated symptoms may receive conflicting information
about the cause of those symptoms. One example involves a
43 year old woman experiencing significant confusion and
memory loss, who was told by her gynecologist that she
likely was having some type of premenopausal syndrome, and
that her problems were not implant related, while another
physician believed her implants may be the culprit (W. B.
Jones, personal communication, October 7, 1994). For women
experiencing significant difficulties, such conflicting
information can be quite distressing.
Another reason why it is imperative that more data is
compiled as to the side effects of silicone breast implants
is so that informed decisions about the surgical removal of
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implants (explantation) can be made. This procedure
generally costs between $1,500 and $30,000, and typically is
not covered by insurance companies (Vasey & Feldman, 1994).
It is essential that all types of symptoms associated with
silicone implants be - documented, so that women with
difficulties not likely to be implant related do not undergo
explantation unnecessarily.
CHAPTER II
METHOD
Subjects
Files on silicone breast implant patients from the
offices of two neuropsychologists in private practice were
selected for use in the study. Supporting neurological data
was available for 16 subjects, and immunological data were
available on 19 subjects. Each of the files involve women
who were 18 years old or older at the time of the
evaluations. All of these women either had silicone breast
implants at the time of the evaluations, or at some time
previous to the evaluations. Data to be used in this study
were archival, and all identifying information was removed
during the coding process to ensure patient confidentiality.
This data set of 38 files represents the entire population
of silicone breast implant patients evaluated by these
service providers who have undergone neuropsychological
testing.
Materials
Data selected from the files for entry originally
included the following measures: the Halstead- Reitan
Neuropsychological Battery, Wechsler Adult Intelligence
Scale-Revised, the Controlled Oral Word Association Test,
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22
Paced Auditory Serial Addition Test, Recognition Memory
Test, the visual reproduction and logical memory subtests
from the Wechsler Memory Test, Rey Complex Figure Test,
Minnesota Multiphasic Personality Inventory, Beck Depression
Inventory, 22 channel Electroencephalogram (EEG),
Quantitative Electroencephalogram (QEEG), SPECT scan, and/or
other event related potentials, peripheral neuropathy data
(nerve conduction velocity study), antibody assay, and the
Information Sheet: Breast Implant Cases (Krusz, 1994). The
Information Sheet: Breast Implant Cases is contained in
Appendix A. After data entry began, it became evident that
very few subjects had been administered the Controlled Oral
Word Association Test, the Paced Auditory Serial Addition
Test, the Wechsler Memory Scale, the Rey Complex Figure
Test, EEG, and nerve conduction studies. Because of this,
these measures were deleted from further analysis.
Reliability and Validity of Measures. The Halstead-
Reitan Neuropsychological Battery is a standard battery of
tests designed to test the biological integrity of the
brain. This test battery yields the Impairment Index and
the General Neuropsychological Deficit Score as composite
scores, and is comprised of the following eleven subtests;
Lateral Dominance Examination, Reitan-Indiana Aphasia
Screening Test, Finger Tapping Test, Grip Strength, Sensory
Perceptual Examination, Rhythm Test, Speech-Sounds
Perception Test, Trail Making Test, Tactual Performance
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Test, and Category Test. The battery has been shown to have
sufficient validity. A study involving 50 brain damaged
subjects matched on gender, age and education with 50
control subjects showed differences between the two groups
on all subtests significant at the .001 level (Reitan,
1955).
The Wechsler Adult Intelligence Scale-Revised (WAIS-R)
is a commonly used measure of intellectual functioning.
Test-retest reliability of the WAIS-R has been found to be
.96. Construct validity has also been shown to be
sufficient, with comparisons with the Wechsler Bellevue
Intelligence test and the Wechsler Adult Intelligence Scale
yielding a correlation coefficient of .69 (Kaufman, 1990).
The MMPI is the personality test often administered to
complement the Halstead-Reitan Neuropsychological Battery
(Anastasi, 1988). The MMPI is made up of three validity
scales, and 10 clinical scales, and has been shown to have
sufficient reliability and validity. Typical test retest
reliability coefficients for the MMPI taken by psychiatric
patients at one to two week intervals were .80 to .85
(Schwartz, 1977). In the standardization sample, eight of
the clinical scales differentiated between a specified
clinical group and a normal control group of approximately
1500 people (Hathaway & McKinley, 1940, 1943). When used
with persons with cerebral damage, the MMPI customarily
yields a profile that reveals some degree of deviation from
24
normal. Persons with cerebral damage often show elevations
on the first three clinical scales, although other
populations without cerebral damage also show elevations on
these scales (Reitan & Wolfson, 1993).
The validity scales of the MMPI have often been used in
an attempt to determine whether subjects are overreporting
symptoms, or faking bad on the MMPI (Rogers, Sewell, &
Salekin, 1994). A commonly cited method for determining
faking bad on the MMPI involve the validity scales F and K.
The F scale was developed to detect deviant or atypical
responses to MMPI items, and is comprised of items that are
endorsed by fewer than 10 percent of adult normals. The K
scale is designed to be a subtle index of attempts to deny
psychopathology (low scores) or to exaggerate
psychopathology (high scores) (Meehl & Hathaway, 1946).
These two validity scales are combined in the formula (F raw
score - K raw score), known as "F - K" index. When the F -
K index yields a high positive number, there is a
possibility that the profile is a fake bad profile (Gough,
1950). There is disagreement as to what cut score is
optimal, with estimates ranging from F - K > 0 t o F - K >
34, with optimum classification achieved with cut scoress of
> 12 and > 16 . For the purposes of our study, we will
employ the formula F - K > 16 as an index of faking bad on
the MMPI, as it has been shown to correctly identify 94% of
MMPI profiles (Berry, Baer, & Harris, 1991).
25
The F - K formula is also used with the MMPI-2, however
changes in the F and K scales on the MMPI-2 necessitated
additional research as to the most useful cut score for the
F - K formula. Recent research indicates the formula F - K
> 7 yields a 87% hit rate for faking bad (Bagby, Rogers,
Buis, & Kalemba, 1994). For an index of faking bad on the
MMPI-2 the formula F - K > 7 will be used for the purposes
of this study.
While the F - K index is commonly used as indices of
exaggerating psychopathology, it primarily relates to faking
bad on the MMPI. It is unclear whether a subject's MMPI
presentation is correlated to their presentation on
neuropsychological measures. It is possible that a subject
may attempt to fake bad on the MMPI but not on
neuropsychological tests, or vice versa. In spite of these
difficulties in inferring faking bad from MMPI indices, we
used the F - K formula in this study because it was a
readily available commonly used index for assessing
malingering/faking bad.
The other measure of personality used in this study is
the Beck Depression Inventory (BDI). This is a 21 item self
report inventory designed to assess depressive
symptomatology. The BDI has been shown to be sufficiently
valid and reliable for inclusion in this study. Internal
consistency reliability was found to be .80 for single
episode depression, .86 for recurrent episodes, and .79 for
26
dysthymia (Beck & Steer, 1993). Test retest reliability was
found to be .90 in a sample of college students when tested
at a two week interval (Lightfoot & Oliver, 1985). The BDI
has been shown to differentiate between Dysthymic and Major
Depression (Steer, Beck, Brown, & Berchick, 1987), and
between Generalized Anxiety Disorder and Major Depression
(Steer, Beck, Riskind & Brown, 1986).
The Information Sheet: Breast Implant Cases (Krusz,
1994) is a symptom checklist designed to elicit specific
information regarding autoimmune symptomology. It is a
checklist consisting of 37 symptoms that are checked yes or
no, and questions about type of silicone implant, and dates
of surgery. This self-report measure was recently designed,
and no validity or reliability information is available.
The quantitative EEG is a statistical analysis of the
quietest background activity available on an EEG recording.
The data are subjected to a neurometric analysis and
compared against controls from a normative database. Other
neurological data includes Brain Spec Scans. This test
involves a complex computer analysis of the brain's blood
flow and function.
Procedure
The procedure of this project entailed organizing and
entering data from the above described measures.
Neurological data was collected by a neurologist, and
qualified technicians. Brain Spec scan data was collected
27
by Advanced Metabolic Imaging of North Dallas, a laboratory
certified by the American College of Nuclear Physicians.
The neuropsychological data was collected by
neuropsychologists and neuropsychological testing
technicians, who are advanced graduate students in
psychology with additional specialized training in
neuropsychological testing and scoring techniques. Twenty
of the subjects were administered the neuropsychological
battery by the principal author of the study, seven were
tested by a neuropsychologist, and 11 subjects had been
tested by other neuropsychological testing technicians.
CHAPTER III
RESULTS
Description of Sample
The study group consisted of 38 files containing
neuropsychological evaluations from silicone breast implant
patients. Six files were dropped from further analysis due
to history of additional CNS insult. The remaining 32 cases
consisted of White, right handed females, who ranged in age
from 3 0 to 64 years (M = 45.81. SD = 8.69). Two patients
had undergone augmentation following mastectomy. One
mastectomy patient had been diagnosed with breast cancer,
and one had severe fibroid tumors of the breast. All other
patients had recieved implants for cosmetic reasons. The
minimum number of years of education completed was 7, and
the maximum was 18 (M = 13.41, SD = 2.20). Eleven patient
files contained immunologic and neurological data in
addition to a complete neuropsychological battery. Five
files contained only neurological data in addition to a
neuropsycholgical evaluation, and 8 files contained only
immunolgical data in addition to a neuropsycholgical
evaluation. Only 7 cases contained neuropsychological data
with no supporting neurological or immunologic data.
28
29
The minimum number of years exposed to silicone
implants was 4, and the maximum was 27 (M = 14.10, SD =
5.95), representing a total of 451 years of implant
exposure. Sixteen of the files (50%) contained medical
documentation of implant rupture, which involved silicone
gel spilling outside of the envelope. Twenty six of the
files contained information on capsular contracture. Of
those 26, 12 patients (46.2%) had experienced capsular
contracture.
While ten patients still had silicone implants in place
at the time of the evaluation, twenty two women (68.8%) had
undergone surgical removal of the implants. Of this group,
only two (9.1%) had their silicone implants replaced with
saline breast implants. The minimum number of months
elapsed since explantation was 0, and the maximum was 39 (M
= 11.36, SD = 9.12).
Description of WAIS-R Performance. The mean Full Scale
IQ (FSIQ), Performance IQ (PIQ), and Verbal IQ (VIQ) values
for the sample fall within the Average range of performance.
The average VIQ/PIQ disparity was 7.8 points (SD = 4.8).
The four Wechsler subtests most useful in determining
premorbid intellectual abilities ("Hold" subtests) include
Information, Comprehension, Similarities and Vocabulary
(Reitan & Wolfson, 1993). Means for these subtests were 9.3
(SD = 2.1), 9.0 (SD= 1.8), 9.8 (SD = 2.1) and 10.3 (SD =
2.3) respectively. Analysis of WAIS-R subscales indicates
30
that the highest mean scaled score was on the Vocabulary
subtest. This finding is consistent with the observation
that the Vocabulary subtest is relatively insensitive to
cerebral damage (Reitan, Horn & Wolson, 1988). These pattern
of test scores indicate that on the whole, the sample
experienced relatively normal neuropsychological maturation
during the developmental period.
The lowest scaled scores were on the Digit Symbol
subtest (M = 8.2, S D = 2.7). This finding is also
consistent with the observation that the Digit Symbol
subtest is the most sensitive of the Wechsler subtests to
cerebral impairment (Doehring, Reitan, & Klove, 1961; Klove
& Reitan, 1958; Reitan, 1955). While each of the means of
the "Hold" tests were higher than the mean of the Digit
Symbol subtest, paired t tests revealed the means of
Vocabulary and Similarities to be significantly higher
(t(31) = -.3.47, e <.005), and (t(31) = -3.24, p c.005)
respectively. Mean values for the subtests of the WAIS-R
are located in Table 1, located in Appendix B.
Description of Halstead-Reitan Neuropsychological
Battery fHRNB) performance. The most sensitive indicators
of neuropsychological impairment in the HRNB are the
Impairment Index and the GNDS. These two scores are
composite scores made up of other scores in the battery, and
general indicators of neuropsychological impairment.
Specific tests in the Battery known for their sensitivity to
31
the biological condition of the brain are the Category Test,
Tactual Performance Test (TPT) Total Time, TPT Memory, TPT
Localization, Rhythm Test, Speech Sounds Perception Test,
Dominant Hand Tapping, and Part B of the Trail Making Test.
Means and standard deviations for these measures are
reported in Table 2 located in Appendix B.
Description of Personality Test Results. Twenty-seven
subjects had completed the MMPI, and two subjects had
completed the MMPI-2. Results of the MMPI were included for
analysis. To maintain continuity with related research,
subjects qualified as experiencing significant emotional
disturbance if they met the qualifications determined by
Denberg, Carbotte and Denberg (1987). These criteria define
emotional distress as T scores above 7 0 on two or more of
scales 2, 4, 6, 7, 8, and 9 on the MMPI. These authors do
not include scales 5 and 0 since those scales are relatively
insensitive to the presence of acute distress, and 1 and 3
because physical illness might elevate these two scales.
According to these criteria, 34% of the SLE patients in the
Denberg, Carbotte & Denberg (1987) study experienced
significant emotional distress at the time of evaluation.
This is in contrast to our finding that 70% (19) of our
sample experienced significant emotional distress at the
time of the evaluation. The most commonly elevated scale in
our sample was scale 2 (Depression), with 22 patients (81%)
scoring at or above a T score of 70. Pearson product moment
32
correlation revealed no significant relationship between
depression and GNDS (r = .24, p = .24) or depression and
years exposed to implants (r =-.25, p = .21). A biserial
correlation revealed no significant relationship between
patients who had been -explanted versus patients who still
had their implants (r = .29, p = .15).
F - K scores were computed for all 27 MMPI profiles,
and for the two MMPI-2 profiles. Analysis revealed that no
subject had an F - K MMPI score above the cutoff of 16.
Neither of the MMPI-2 profiles yielded a F - K score in the
"fake bad" range (F - K > 7). These data indicate that it
is unlikely that these patients were attempting to malinger
on the MMPI or MMPI-2.
Findings from the Beck Depression Inventory were
consistent with the MMPI test results. A Pearson product
moment correlation revealed that the MMPI Depression Scale
(Scale 2) was highly correlated with the Beck Depression
Inventory (r = .76). Mean BDI scores for breast implant
patients of 22.6 (SD = 11.2) were well above the cutoff of
16 used to indicate the presence of significant depression
(t(26) = 3.08, p <.05). Means and standard deviations for
the personality tests are reported in Table 3 located in
Appendix B.
Immunological findings. Nineteen files contained
laboratory results including Antinuclear Antibody (ANA)
titer. Twelve of these subjects (63.2%) had abnormally high
33
ANA levels. ANOVA revealed no significant difference on
GNDS between subjects with abnormal ANA titer and subjects
with normal ANA titer (F(l,17) = .008, E = .93). Fourteen
files contained laboratory results which included Rheumatoid
Factor titer. Nine of these subjects (64.3%) had abnormally
high Rheumatoid Factor levels.
Electrophysiological findings. Quantitative EEG
results were available for 13 patients. Four patients who
had not had a QEEG had undergone SPEC Scanning. Therefore,
electrophysiological data on brain functioning was available
on 16 (50%) of our sample. All 16 (100%) of the available
QEEG and records contained noted abnormalities. The most
common abnormality noted was some type of abnormality in the
temporal lobe(s), present in 14 (88%) of the cases. Frontal
abnormalities were noted in 10 (63%) of the cases. The
least common abnormalities noted were located in the
parietal lobe, with 6 cases (38%) exhibiting these type of
abnormalities.
The temporal lobes are known to be involved in the
storing and retrieval of memories, and temporal lobe
difficulties have been linked to memory difficulties. An
one way analysis of variance was computed to determine
whether subjects with temporal lobe problems were
significantly more impaired on a memory task than subjects
without temporal lobe problems. The memory task used was
the Memory component of the Tactual Performance Test. While
34
this task does involve memory, it does not specifically tap
into temporal lobe abilities. However, it was the only
component of the battery that is specifically designated as
a memory task. ANOVA revealed no significant difference
between the two groups (F(l,15) = .18, p = .68).
Another HRNB test that known to be localized is the
Finger Tapping Test. This measure is sensitive to deficits
in the posterior frontal lobe area. To determine whether
subjects with frontal lobe abnormalities were significantly
more impaired on the finger tapping test than subjects
without frontal abnormalities, an ANOVA was used. The ANOVA
revealed no significant differences between the two groups
(F(l,15) = .32, E = -58).
Neuropsychological Test Scores of Silicone Implant Patients
Versus Published Cutoff Scores
Paired t tests revealed the sample to differ
significantly on several measures from Reitan's 1971 cutoff
scores used for inferring brain damage. A Bonferoni
correction was used to adjust for familywise error, yielding
an adjusted p of .006. The mean Impairment Index and GNDS
of the silicone implant patients were significantly more
impaired than the cutoff scores (t(29)= 4.63, pi <.001) and
(t(27) = 3.85, p = .001) respectively. Analysis of the
component tests of the HRNB revealed that the sample showed
significant deficits on three of the eight most sensitive
parts of the HRNB. These measures include the Category
35
Test (t (31) = 4.17, e <.001), TPT Memory (t(31) = 5.82, e
<.001), , and dominant hand Finger Tapping (t(29) = -7.28, p
c.001). The silicone implant group was not significantly
more impaired than the cutoff scores for inferring brain
damage on TPT Total Time (t(31) = 1.82, 2 = -08), Trails B
(t(31) = -.07, p = .94), Rhythm Test (t(30) = .77, p = .45)
or on the Speech Sounds Perception Test (t(30) = -1.66, p =
.11). While the scores on the Localization component of the
TPT approached significance, (t(31) = -2.04, p = .05), they
did not meet the significance level of jo < .006 required by
the Bonferoni correction. Table 4 includes a comparison of
HRNB performance of silicone implant patients to published
cutoff scores used for inferring cerebral deficits. Table 4
is located in Appendix B.
Comparison of Silicone Breast Implant Group to Published
Scores From SLE Patients
Denburg, Carbotte and Denberg (1987) published
normative data from a sample of SLE patients. SLE patients
were classified into one of three groups; as Lupus with
active neuropsychiatric symptomology, inactive symptomology,
or Lupus without neuropsychiatric symptomology. The SLE
group tended to be younger than the silicone implant group,
with mean ages of 36.8 years, and 45.8 years respectively.
The SLE group tended to have completed fewer years of
education than the silicone implant group, with mean years
of eduction completed 11.8 years, and 13.4 years
36
respectively. The silicone breast implant group was
compared to mean values for the three groups of SLE patients
using one sample t tests on Trails A, Trails B, Finger
Tapping Dominant, Finger Tapping NonDominant, WAIS-R FSIQ,
WAIS-R VIQ, and WAIS-R PIQ. A Bonferroni correction was
used to adjust for familywize error, yielding an adjusted JD
of .02. The silicone implant group did not significantly
differ from the SLE patients on any measures with the
exception of the WAIS-R values. A comparison of the
silicone implant group to the three groups of SLE patients
on Trails A and B and Finger Tapping is presented in Table
5. The silicone implant group had significantly lower WAIS-
R FSIQ, VIQ and PIQ values than all three SLE patient
groups. A comparison of the silicone implant group to the
mean of the three groups of SLE patients on the WAIS-R is in
Table 5, located in Appendix B.
Length of Exposure to Silicone Implants and
Neuropsychological Deficits
A hierarchical regression was used to determine whether
length of exposure to silicone breast implants was related
to severity of neuropsychological deficits on the HRNB. The
HRNB composite scores (Impairment Index and GNDS) were used
as indicators of neuropsychological deficit. Analysis
revealed that number of years of exposure to silicone breast
implants does not predict greater impairment on these two
variables (F(l,30) - .70, p = .50). Beta weights for the
37
variables Impairment Index and GNDS were .21 and .24
respectively.
The relationship between length of exposure and
severity of deficits was also explored using Pearson product
moment correlations. These analyses revealed that there was
no significant relationship between length of time exposed
to implants, and the Impairment Index (r = .21, p = .26), or
between length of time exposed to implants and GNDS (r =
.11, p = .54).
Patients With Silicone Implants Versus Patients Who Have Had
Their Implants Removed
A one way MANOVA revealed no significant differences on
three variables between patients who had undergone
explantation and patients who still had silicone implants in
place at the time of evaluation. The three variables used
were the two HRNB composite scores (Impairment Index and
GNDS) and Trails B. Although the multivariate F was
significant (F(3,27) = 4.12, p = .016), breakdown into
univariate analyses revealed no significance for any of the
three variables [Impairment Index (F(l,29) = .70, p = .41),
GNDS (£(1,29) = 1.63, p = .21), Trails B (£(1,29) = 2.37, p
= .13)]. Stepdown F test revealed GNDS to be the only
significant variable when Impairment Index was covaried out
(F(l,28) = 7.53, p = .01). These results are in question
however due to the fact that the data violated the
38
assumption of homogeneity of regression (F(l,27) = 6.97, p =
.014).
Patients With Documented Rupture Vs. Patients with
Documented Intact Implants
ANOVA was used to determine whether patients with
ruptured implants were significantly more impaired on the
GNDS than patients with implants not shown to be ruptured.
Analysis revealed that patients with ruptured implants were
not significantly more impaired on the GNDS than patients
whose implants had been shown to be intact (F(l,20) = .001,
E = -98)
CHAPTER IV
DISCUSSION
While the sample group was composed entirely of white
females, this is not inconsistent with the general
population of silicone implant patients. Other studies from
the United States are also comprised largely of white
females. The sample differed from most current studies in
that our patients tended to be older (mean age = 45.81
years) and to have been exposed to implants longer (mean
years of implant exposure = 14.10).
Fifty percent of patient files contained medical
documentation of an implant rupture. In most cases, the
rupture was diagnosed during explantation, therefore some of
the remaining 50% of our sample may have had silent or
undetected ruptures. This high incidence of implant rupture
is inconsistent with 4% to 16% estimates of implant ruptures
in the general population of breast implant patients. The
incidence of implant rupture in our study is similar to that
of Patten & Shoaib (1995) who noted 60% of their explanted
Human Adjuvant Disease patients had experienced at least one
ruptured implant.
Of the 26 files with information on capsular
contracture, 46.2% had experienced this side effect. This
39
40
is above the 10% to 40% estimates of capsular contracture in
the general breast implant population (Bridges & Vasey,
1993). The high incidence of implant failure and capsular
contracture indicates that the sample group was likely to be
comprised of individuals who were more sensitive to silicone
than the majority of silicone breast implant patients.
Overall, the sample group tended to present with a
valid testing profile consistent with mild generalized
cerebral deficits. Group performance on IQ measures fell
within the Average range, indicating adequate premorbid
neuropsychological development. Analysis of WAIS-R
intratest performance revealed group performance on the
Digit Symbol subtest to be lower than group performance on
any of the other subtests. Patients in the sample group
tended to score in the mild to moderate range of impairment
on the Impairment and in the mild range of impairment on the
GNDS, the two most sensitive HRNB measures. This pattern of
test results is consistent with mild to moderate
neuropsychological impairment of a diffuse nature acquired
during adulthood.
Personality measures revealed that the sample was
experiencing significant emotional distress and depression
at the time of evaluation. This is a typical type of
reaction to a mild brain injury (Gualtieri, 1995). It is
commonly known that brain damaged patients endorse more MMPI
symptoms than normals. Studies indicate that brain damaged
41
MMPI profiles are characterized by primary elevations on the
neurotic triad (Scales 1, 2, 3) and secondary elevations on
the psychotic scales (Scales 6, 7, 8) (Dikmen, & Reitan,
1977) .
Persons unfamiliar with the intricacies of brain injury
may misunderstand this depressive reaction, and instead
believe this type of patient is hysterical or malingering.
This is a serious problem faced by many silicone breast
implant patients with organic brain syndrome. Because they
look much like anyone else, are typically verbal, and retain
their premorbid intelligence level, their deficits are
missed or dismissed by many laypersons and professionals.
This can be a constant source of frustration for persons
with toxic brain syndrome due to implants. These
frustrations are likely a contributing factor to the high
degree of emotional distress experienced by the sample
group.
Neurological and immunologic data was only available
for part of the sample, but was included in the study to
provide a better picture of the subject group. The QEEG and
Spec scan data that was available strongly supported our
neuropsychological test findings. All of the patients with
electrophysiological test data had exhibited abnormalities,
the most common being temporal lobe abnormalities.
Immunologic findings also tended to be positive. Sixty-
three percent of the subjects who had undergone ANA testing
42
had abnormally high ANA titer, and 64% of those who had
undergone Rheumatoid Factor testing had abnormally high
Rheumatoid Factor titer.
Halstead-Reitan Neuropsychological Battery results for
the sample revealed some striking deficits. The patient
group scored more impaired than the cut scores used for
inferring brain damage on several of the most sensitive
measures in the battery. In addition to impaired composite
scores (Impairment Index and GNDS), the sample showed
significant deficits on the Category Test, TPT Memory,
dominant hand Finger Tapping, and deficits approaching
significance on TPT Localization. Scores for the sample
group were within the normal range on Trails B, Rhythm Test,
and Speech Sounds Perception Test.
These findings may be indicative of a
neuropsychological profile of an atypical neurologic
disorder due to silicone toxicity. In general such a
profile would consist of the following components. The
patient is likely to exhibit average WAIS-R intelligence,
with the Digit Symbol subtest being the lowest of the
subtest scores. Personality testing is likely to reveal
scores in the depressed range on the Beck Depression
Inventory. The MMPI typically shows a valid profile with
multiple elevations, indicating emotional distress.
Neuropsychological testing with the HRNB is likely to show
marked deficits in abstract reasoning and executive
43
abilities (Category Test), in incidental memory (TPT Memory,
TPT Localization), and in upper extremity motor speed
(Finger Tapping). Performance on measures of attention and
concentration (Speech Sounds Perception Test, Rhythm Test)
is likely to be in the normal range', as is psychomotor speed
(Trails B).
Comparison of the silicone implant group to published
norms for patients diagnosed with Systemic Lupus
Erethrymatosus (Denberg, Carbotte & Denberg, 1987) revealed
the two groups to differ significantly only on WAIS-R
scores. Trails A, Trails B, Finger Tapping Dominant Hand
and Finger Tapping NonDominant Hand did not show significant
differences between the two groups. These findings are not
surprising, due to the similarities between the systemic
disorder caused by silicone toxicity and SLE. The two
disorders share so much in common that many silicone breast
implant patients are diagnosed with atypical Lupus (Lewy,
1994).
Although the mechanism of pathogenesis is not known,
the silicone syndrome bears striking similarities to SLE, a
known autoimmune disorder. The results of this study are
consistent with research indicating commonalities between
silicone implants and immune symptoms.
Length of exposure to silicone gel breast implants was
not a good predictor for severity of neuropsychological
deficits on the HRNB. There are several reasons why our
44
data revealed no correlation between these two variables.
Firstly, the sample consisted of women who had been exposed
to implants on the average of 14 plus years. While all
implants are noted to bleed silicone through the intact
shell, the viscosity of the gel is likely to influence rates
of gel bleed, and consequently the amount of silicone gel
released into the patient's system. Half of our sample had
experienced a rupture of one or both implants, drastically
influencing the amount of silicone gel released into the
woman's system. The amount of gel released into a patient's
system appears to be a complicated equation, and cannot be
reliably estimated simply by length of exposure. In a much
larger sample, however it may be possible to assume that on
the average, the more years of implant exposure, the more
silicone the patient has been exposed to. Finally, the
intraindividual differences in reactivity to a toxin is
likely to account for some of the variability found.
Patients who had undergone explantation were not found
to be significantly different on neuropsychological testing
from patients who still had their implants. This analysis
was done in an attempt to investigate the observation that
many silicone adjuvant disease patients experience a
lessening of symptoms after explantation. This may have
been an inappropriate analysis for the sample group for
several reasons. Patients who had undergone explantation
surgery may have been experiencing greater difficulties
45
previously, and their performance on our testing could have
represented a lessening of their condition. Also important
is that the explanted group had only been implant free for
less than a year on the average, and it takes about two
years for most patients symptoms to begin to abate. It
would be logical to assume that women who undergo
explantation surgery experience more implant related
symptoms than those who do not, however financial reasons
may also influence which patients undergo the procedure.
Finally, while most silicone adjuvant disorder symptoms are
said to decrease after explantation, it is unclear whether
the CNS deficits can be expected to improve. Due to the
complexity of the intervening variables, it is not
surprising that the explanted group did not appear
significantly different than the non-explanted group on the
HRNB.
A comparison of explanted patients with documented
rupture versus explanted patients with intact implants
revealed no significant differences between these two groups
on GNDS scores. This type of analysis was innapropriate to
perform on the entire population, due to the fact that it is
impossible to determine which non-explanted patients had
silent ruptures at the time of the evaluation.
The issue of malingering is a valid concern for
researchers in this area, due to ongoing legal battles
surrounding breast implants. No specific measure of
46
malingering was included in the files used for the study
however. To address this issue, we utilized the F - K index
of faking from the MMPI. Analysis of the 29 available MMPI
and MMPI-2 F - K indices of faking bad revealed that only no
subjects had profiles in the faking bad range. These
results offer no evidence that the sample group exaggerated
their symptoms on the MMPI.
It is unclear whether we can assume that the sample
group did not attempt to malinger on the remainder of the
test battery. However, in addition to our MMPI findings,
several other points can be made in relation to malingering.
First, we observed the correct profile on tests of premorbid
ability, such as the WAIS-R. The patient group also showed
consistent abnormalities on neurological and immunological
measures. QEEG abnormalities were most commonly located in
the temporal lobe. Similar QEEG data was found by Hoffman,
Stockdale, Hicks, and Schwaninger (in press). Finally, our
results appear to be valid because they show similarities to
the findings of the only other existing study (Brown et al.,
in press) involving the neuropsychological performance of
silicone breast implant patients.
In summary, it appears that a significant number of
silicone implant patients with a history of implant related
problems and/ or atypical neurologic disorders can be
expected to exhibit significant neuropsychological deficits
on the HRNB. These data suggest that this patient group
47
tends to suffer from a mild to moderate, diffuse organic
brain syndrome that can be observed on physiological and
neuropsychological measures. Typical HRNB battery
performance includes average WAIS-R, Speech Sounds
Perception Test, and Rhythm Test performance, with deficits
evident on Impairment Index, GNDS, Category Test, Finger
Tapping, TPT Memory and Localization. The patient group
tended to be experiencing significant emotional distress and
depression. Spec scan and QEEG data for a subset of the
sample confirmed physiological and structural CNS deficits,
most often in the temporal lobe.
Limitations of Study
The main limitation of this study was the small sample
size of patients with silicone gel breast implants. This
was a difficult limitation to overcome, because of the
involved nature of the test battery. Each patient file
represented a minimum of eleven hours of patient time and a
considerable expense. The lack of a control group also was
a significant limitation, but again the time and expense
that would have been involved would have been great.
Another limitation of the study also stemmed from the
small sample size. Some researchers report symptom
differences in the implant group by type of implant.
Presumably these symptom differences are due to the varying
degrees that the implants leak their contents, and to the
differing chemical composition of the silicone gel. If a
48
great number of files were available, we would have been
able to subdivide our implant group by type of implant.
Research Directions
Future researchers may find it productive to continue
to explore neuropsychological deficits and silicone gel
breast implants. The HRNB seemed especially well suited to
this type of research, as it is a standard battery that is
commonly used by neuropsychologists. Additional measures of
malingering and motivation may be useful, due to the
litigation surrounding breast implants. It may be
interesting to compare the performance of patients involved
in litigation and patients not involved in litigation.
Future research to replicate our results would be
beneficial, as this is the first study of this kind using a
sufficient sample size.
One area of future research that may help to document
the CNS deficits associated with silicone adjuvant disease
involves the children of implant patients. Some physicians
are currently recommending explantation for implant patients
contemplating pregnancy, because silicone has been observed
in breast milk, and to cross the placental barrier (Lewy,
1994). No studies exist that explore pediatric CNS
difficulties related to prenatal silicone exposure, and/or
silicone transmitted through nursing. As medical
recommendations are being made for pediatric silicone
49
exposed patients, studies examining this group would be
useful.
APPENDIX A
INFORMATION SHEET: BREAST IMPLANT CASES
50
51
Information Sheet
(Breast Implant Cases)
Full name of patient:
Full name of patient's present spouse:.
Address:
Telephone No. at work:.
Telephone No. at home:.
Facts about your implant surgery:
Date surgery performed:
Hospital or clinic of surgery:.
Surgeon performing implantation:.
Why were implants placed? Purely cosmetic,
reconstruction, following mastectomy, or other?.
Facts about removal of your implants (if applicable):
Not removed:
Date implants removed:.
Location of surgery:
Surgeon performing implant removal:.
Manufacturer of implants:
Name of manufacturer (if known):
Name of implant (if known):
Symptoms associated with implants:.
52
Do you presently or have you previously had any of the
following?
Symptom Beginning Ending
Nipple Discharges Yes No_
Memory difficulties Yes No_
Shooting pains on
limbs and trunk Yes No
Pins and needles or
numbness on limbs/
trunk Yes No
Fatigue Yes No
Joint pain Yes No
Rash in breast
area Yes No
Burning in breast Yes No
area Yes No
Headaches Yes No
Swelling in face
or eyelids Yes No
Inflammation in
mouth or nasal
area Yes No_
Bitter taste in
mouth Yes No
Date Date
53
Unusual lumps in
breasts Yes No_
Nausea/vomiting Yes No_
Hair loss/ thinning
of hair Yes No_
Abnormal periods Yes No_
Change of shape of
breasts Yes No_
Chronic flu-like
symptoms Yes No_
Irritation of skin
in bra area Yes No_
Severe/chronic
cough Yes No_
Swollen glands Yes No_
Mouth sores Yes No_
Prolonged difficulty
sleeping Yes No_
Night sweats Yes No_
Swollen joints Yes No_
Prolonged/persistent
diarrhea Yes No_
Prolonged fluid
retention Yes No_
Prolonged temperature
elevation Yes No
54
Change in skin
texture Yes No_
Prolonged nasal
congestion Yes No_
Prolonged muscle
spasms Yes No_
Prolonged chest
pains Yes No_
Prolonged
dizziness Yes No_
Dry eyes Yes No_
Face pain or
tenderness Yes No_
Recurrent yeast
infections Yes No_
Kidney problems
too much urine/
too little urine Yes No
Other symptoms (Please specify in detail- use additional
paper, necessary).
APPENDIX B
TABLES
55
56
Table 1
Mean WAIS-R 10 Values for Silicone Breast Implant Patients
M SD n
Verbal Subtests
Information3 9.34 2 . 10 32
Digit Span 9 . 06 2.21 32
Vocabulary3 10. 28 2 . 30 32
Arithmetic 9.38 2 .31 32
Comprehension3 9.00 1.76 32
Similarities3 9.81 2 . 05 32
Performance Subtests
Picture Completion 8 . 50 2 .31 32
Picture Arrangement 8.44 2 .14 32
Block Design 8 . 66 2.22 32
Object Assembly 8.31 2.38 32
Digit Symbolb 8. 19 2.73 32
VIQ 98 . 19 8.24 32
PIQ 97 . 16 10.14 32
FSIQ 96.91 8. 12 32
aThese are the subtests most useful for determining premorbid IQ.
bThis is the subtest most sensitive to cerebral impairment.
57
Table 2
Means of Silicone Implant Patients on the Most Sensitive
Components of the HRNB
M SD n
Composite Scores
Impairment Index . 59 . 22 30
GNDSa 35. 50 13 . 04 28
Subtest Scores
Category 65 .41 26 . 35 32
TPTb Total Time 18. 89 9. 91 32
TPTb Memory 7 . 03 1. 98 32
TPTb Localization 3 . 22 2. 17 32
Rhythm 25 .74 5 . 39 31
Speech 6 .81 4 . 00 31
Tapping (Dominant Hand) 35 .21 11 .12 30
Trails B 85 . 37 47 .39 32
aGlobal Neuropsychological Deficit Scale
bTactual Performance Test
58
Table 3
Mean Personality Test Scores of Silicone Breast Implant
Patients
M • SD n
Minnesota Multiphasic Personality Inventory Scales
Validity Scales
L 54.33 12.55 27
F 63.96 12.14 27
K 54.67 8.15 27
Clinical Scales
1 (Hypochondriasis) 84.00 13.08 27
2 (Depression) 81.67 14.79 27
3 (Hysteria) 84.30 11.50 27
4 (Psychopathic Deviate) 69.33 10.88 27
5 (Masculinity-Femininity) 43.22 7.75 27
6 (Paranoia) 69.96 12.96 27
7 (Psychasthenia) 70.44 13.18 27
8 (Schizophrenia) 78.78 14.35 27
9 (Hypomania) 55.93 10.76 27
0 (Social Introversion) 59.70 11.24 27
Beck Depression Inventory (BDI) Total Score
BDI 22.63 11.17 27
59
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