General Neurology: “Mind Bendingâ€‌ Neurologic Neurology:...

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Transcript of General Neurology: “Mind Bendingâ€‌ Neurologic Neurology:...

  • Metropolitan Underwriting Discussion Group

    General Neurology: Mind Bending Neurologic Conundrums

    Dave Rengachary, MDVice President and Medical AdvisorJanuary 26, 2015

  • Transient Ischemic Attacks (versus mimics)


  • 3

    We often receive attending physician statements where we have difficulty telling whether an individual had a TIA. We already know what TIAs are and how to apply ratings for these events. We need some guidance on situations where it is not entirely certain that a person had an actual TIA or whether it might be another condition like migraine

  • TIA: Previous definition

    Sudden focal neurologic deficit lasting less than 24 hours, presumed to be of vascular origin, and confined to an area of the brain or eye perfused by a specific artery

  • TIA: New Definition (AHA/ASA)

    a brief episode of neurologic dysfunction caused by focal brain or retinal ischemia, without evidence of acute infarction

    Easton JD et al. Stroke. 2009; 40:228 1

  • Causes of TIA mimics

    Amort M et al. Cerebrovascular Diseases. 2011;32:602

    Diagnosis of Mimic PercentSeizure 44Migraine 23Psychogenic 7Hypertensive encephalopathy 4Transient Global Amnesia 4Sepsis 4Hypoglycemia 2Benign Paroxysmal Vertigo 2Cerebral venous thrombosis 2Brain Neoplasm 1Subarachnoid hemorrhage 1Peripheral nerve lesion 1*Syncope ??

  • Symptoms Predictive of TIA mimic

    Headache - no mechanism whereby TIA should cause headache Memory Loss (*see below!) Blurred vision (as opposed to loss of vision or diplopia) Syncope Recurrent stereotyped episodes with negative workup Symptoms that do not conform well to a single artery - generalized

    symptoms with a gradual or hazy onset rather than focal sudden onset symptoms ("weak" all over, "dizzy)

    Lack of other vascular risk factors

  • Symptoms and TIAs

    Sudden onsetWeakness face/arm/legSlurred speechAble to walkDizzinessSeizureLOCConfusion



    Stroke 2006; 37: 769-75 13

    Lancet 2005; 4:727-34 14

  • Prognosis of TIA mimics

    At 3 months, stroke, recurrent TIA and myocardial infarction were absent in patients with TIA mimics but occurred in 13 (5.2%), 20 (8.1%) and 3 (1.2%) TIA patients, respectively.

    Amort M et al. Cerebrovascular Diseases. 2011;32:62 1

  • Transient global amnesia

    One of the most interesting neurologic phenomenon happens in entirely normal people with little medical history

    Pathogenesis unknown Key feature is sudden and profound inability to form new memories,

    repetition of questions lasting on the order of hours without focal symptoms

    Often follows exercise Workup typically normal (MRI, ECHO, carotids, EEG) Entirely different prognosis

    Low rate of recurrence (6%) Lower rate of stroke, myocardial infarction or deathPantoni Let al. European Journal of Neurology. 2005; 12: 350


  • Funny Spots on the Brain

  • Notation is made of white matter hyperintensities these are nonspecific findings of unlikely clinical significance. However..

  • cannot exclude Lyme disease, vasculitis, multiple sclerosis and demyelinating variants, small vessel strokes, dementia, migrainous phenomenon, hypertensive disease, microbleeds..

  • .clinical correlation is advised(please dont sue me)

  • 15Boddaert et al. 9 Creative Commons Attributions License

  • White matter hyperintensities Small vessel ischemic changes Leukoaraiosis Lacunar infarcts Microvascular Changes High Signal Intensity Areas (HSIA) Age related changes FLAIR hyperintensities Dilated Virchow-Robin Spaces UBOs (Unidentified Bright Objects)

    Different names for the same game


  • Complicating matter further these and other incidental findings are quite common - NEJM article by Vernooij et al.6 found that about one in ten people in the general population had a incidentaloma on imaging.

    Studies also vary significantly in terms of what is counted as a white matter change size? Number?

    White Matter Hyperintensities


  • ??? 25% risk of

    MS with RIS8

    Mortality Ratio of 2.3

    Hazard Ratio of 2.9

    Hazard Ratio of 3.1

    Stroke Dementia



    Clinical Implication of White Matter Hyperintensities7


  • Age


    Vascular Risk Profile




    Progression (or stability)

    Factors to consider and Red Flags


  • Mild Carotid Stenosis

  • We receive carotid ultrasound reports that show lesions in the range of 10-49% obstruction. How worried should we be about this degree of obstruction?

    Non-stenotic carotid disease

  • 0








    0 10 20 30 40 50 60 70 80 90 100






    Diameter Stenosis %


    Velocity versus Degree of Stenosis

    Adapted from Zwibel et al.10

  • ulceration complex heterogeneous soft intraluminal thrombus plaque hemorrhage Echo Lucent (high lipid content)

    Bottom line: red flags for non-stenotic carotid lesions

  • Impact of heterogeneous plaque on mortalityPetersen C et al. Cardiovascular Ultrasound 11 Creative Commons Attributions License

  • Carotid Intima Media Thickness (CIMT)

    Abhashi, et al.12 Creative Commons Attributions License

  • Peripheral Neuropathy

  • It is fairly common for us to see applicants with either sensory or motor neuropathies as determined by either clinical history or EMG reports. Which ones should we worry about, and which ones are less concerning?

    Peripheral neuropathy

  • 23% of patients aged 70-7915

    40% of patients over 8015

    Bottom line : isolated absence of sural nerve likely little consequence in terms of morbidity and mortality, especially in the elderly

    Normal loss of sural nerve with aging

  • Time course Demyelinating Any neuropathy that affects the arms or cranial nerves suggests a more advanced

    process Same as indicators for nerve biopsy:

    o Demyelination by NCTso Asymmetry (also indicate an immune process)o Significant functional disability (e.g. foot drop/AFO)o Hereditary history (e.g. Friedreichs ataxia, familial amyloid, certain spino-

    cerebellar ataxias)o Systemic disease (vasculitis, Sjogren's, amyloid)

    Peripheral neuropathy: malignant indicators

  • Red flag indicators in NCT/EMG reports

    "Demyelinating" or "significant slowed conduction velocities"

    "Conduction Block AsymmetricNCT "Acute" "Fibrillations" "Positive Sharp

    Waves" these latter two are indicators of an active recent process very much analogous to contrast enhancement on MRI


  • Diabetic peripheral neuropathy

    57% of patients who died related to complications of diabetes (68% cardiovascular) had neuropathy compared to 23% of those survivors at the end of a 9 year follow up period16.

  • Diabetic autonomic neuropathy

    The 5-year mortality rate in patients with diabetic autonomic neuropathy is three times higher than in diabetic patients without autonomic involvement17

    Silent cardiac ischemia a particular concern

    Vinik et al.18 Creative Commons Attributions License

  • Syrinx

  • Please define a syrinx and help understand the associated mortality.


  • Cross sectional Spinal Cord Anatomy uploaded by Ruth Lawson, Oligo Polytechnic Creative Commons Attribution 3.0 Unported License

  • Hydromyelia



  • Cape like pattern of

    sensory loss

    Bowel and Bladder loss

    Incomplete Paraplegia

    and sensory loss

    Syrinx Symptoms

  • uploaded by Cyborg Ninja license CC Attribution ShareAlike 3.0

  • Very often can be an incidental or equivocal finding (a slightly enlarged central canal is a normal variant)

    Overall rare condition (8.4 out of 100,000, mean age of onset is 30) with a wide variety of underlying structural conditions:

    Etiologies Congenital

    Birth Defects (Chiari Malformations) Tethered Spinal cord

    Acquired Spinal cord tumors Trauma Hemorrhage Meningitis Arachnoiditis Idiopathic

    Surgical indications and outcomes are unclear (are you treating the cause or temporizing a solution? - shunts can become clogged)


  • Good prognostic indicators Idiopathic, asymptomatic, incidental Localized syrinx (< 3 vertebra)

    predicted stability without surgical intervention

    Bad prognosticators: Any progression (clinically or

    radiographically) over time Higher = worse - more to lose

    Syrinx prognostic indicators

    91% of 48 children with idiopathic (but not necessarily incidental) syrinxes remained asymptomatic over 2.5 years19

    In a retrospective study of small incidental syrinxes (2 mm and < 3 vertebral levels) , none of the 32 syrinxes enlarged at 32 months20

  • Arnold Chiari Malformations

  • Please review the various types of Arnold Chiari Malformations and mortality concerns with each.

    Arnold Chiari Malformations


  • 43 uploaded by Christian Linder Creative Commons Attribution Share Alike L