Surgical Options for Parkinson’s Disease

Dr. Zachary LevineWashington Brain & Spine InstituteProf. Neurosurgery GWUDir. Neuroscience and Neurosurgery Holy Cross Health

www.brainsurgery.com

Surgical Options for Parkinson’s Disease

Disclosures

• No Disclosures

History of Surgery for Parkinson’s Disease

1930-1940 “Tractotomy” for tremor and ataxia of all typesSevering connections in the brain

1940’s Stereotactic Pallidotomy and Thalamotomy: Spiegel and WicisBurning holes in the brain

1950’s Thalamotomy and Pallidotomy show promise1960’s – L-DOPA 1970’s - 90’s Resurgence of Pallidotomy: Laitenen1980’s to present Neural Transplantation: Madrazo1990’s Chronic Stimulation1975- treatment for chronic pain1987’s to present for Movement Disorders BenibidNew Methodslesioning of the brain using U/SAlternative method of L-Dopa Administration

Basal Ganglia

Surgery for Parkinson’s Disease

● ABLATIVE SURGERY

○ Tissue destruction

○ Irreversible

○ Non-invasive options

■ SRS

■ MG-FUS

○ Unilateral/Bilateral*

○ Modification requires repeat procedure

● NEUROMODULATION - DBS

○ Non-destructive – based on ablative procedures

○ Reversible

○ Implanted Hardware

■ Brain – wires or “leads”

■ Chest/abdomen – pulse generator

○ Unilateral/Bilateral

○ Modifiable over time without additional surgery

Ablative Surgery

● NON-INVASIVE

○ STEREOTACTIC RADIOSURGERY (SRS)

■ Uses ionizing radiation to create a lesion in the brain

■ No Test – YOU GET WHAT GET based on anatomic targeting

■ Has been done bilaterally

○ MRI Guided – FOCUSED ULTRASOUND (MG-FUS)

■ Uses U/S to produce heat – tissue destruction

■ Test of lesion is done prior to ablation

■ Only approved for unilateral ablation

● INVASIVE

○ RADIOFREQUENCY

■ Uses heat

■ Test of lesion is done prior to ablation

■ Has been done bilateral

● Cognitive issues

Focused Ultrasound for Tremor Predominant PD – Randomized trial

● 27 patients randomized 2:1 FUS vs. Sham to test efficacy of FUS thalamotomy JAMA Neurol. 2017 Dec; 74(12): 1412–1418 – Medically refractory tremor with PD○ Focused Ultrasound Ablation - Thalamotomy: 20

○ Sham: 7

● Tremor rating scores ○ 62% improvement (7 points) – FUS group

○ 22% improvement (2 points) - Sham group

○ Statistically significant. P=0.04

● UPDRS (on Medication - Median Score)○ 8 point improvement (base score of 23) - FUS group

○ 1 point improvement (base score 25) Sham group

● Adverse events○ Hemiparesis (2, transient), orofacial and finger paresthesia (4 and 1 respectively), ataxia (1)

Ablative Surgery Procedure Mg-FUS

OUTPATIENT procedure• Head Shave – necessary to fit the special membrane for

ultrasound penetration

• Place stereotactic frame – no frameless option

• Placed in MRI Scanner

• Initial scans to localize target• Test lesion- no tissue destruction – readjust or confirm

based on testing• Lesion using higher energy U/S• Confirmation scan• Frame removed - D/C to home• Surgical time 3-6 hours

Mg-FUS Complications

IntraproceduralDizzinessNausea

Immediate Post ProceduralAtaxia – difficulty walking (2-3 weeks)Dizziness

Long term ComplicationsAtaxiaTremor recurrence

may require subsequent ablation

NO INFECTIONSNO HARDWARENO INCISIONCANNOT BE MODIFIED

Ablative Surgery Targets

Mg FUSFDA approved for Thalamic target only (unilateral)

Pallidotomy target being researched

SRSApproved for Thalamotomy

Staged Bilateral has been investigatedNot as effective in the pallidum

Neuromodulation

● Alteration of neuronal activity● Chemical – Electrical● Deep Brain Stimulation

○ Using electrical current to change neuronal output

○ Improves some symptoms

○ May produce side effects

○ May lower medication

○ Requires surgical a procedure

○ Neural Prosthetic

Neural Prosthetic

● Electrical stimulation to modulate output from target

● Based on “lesioning” studies● Mimic lesioning with fewer adverse events● Symptomatic treatment

○ Tremor

○ Bradykinesia

○ Rigidity

○ Freezing

○ Dystonia

○ Dyskinesia

Deep Brain Stimulation for PD

"Off"50%

"On" with dyskinesias

23%

"On" without

Dyskinesias27%

"On" with dyskinesias

7% "On" without

dyskinesias74%

"Of f "19%

Baseline Assessment 6 Months after DBS

NEJM Vol 345 No 13 9/27/2001

DBS v. Best Medical Therapy for PD

● Bilateral Deep Brain Stimulation vs Best Medical Therapy for People with Advanced Parkinson’s Disease -JAMA 2009; 301(1) 63-73

● 255 Randomized Patients 121 - DBS, 134 - Best Medical Therapy - compared “on time.” motor function, QOL, Cognitive function and adverse events

● DBS patients gained an average of 4.6h/d of “on time” vs. 0h/d p<0.001● 71% improvement of motor function for DBS vs. 32% medical group p<0.001● 7/8 QOL scores significantly improved with DBS as did the summary of QOL vs. No significant improvement

p<0.001● Cognitive function slightly decreased at the 6month mark with DBS (Not statistically significant)● More adverse events with DBS p<0.001 (49 adverse events with DBS vs 15)

● Conclusion: Deep Brain stimulation is superior to best medical therapy for people with Parkinson’s Disease

DBS Procedure

● Stereotactic – or precision operation based on imaging● Two Stages

○ Lead placement – often done awake

○ Battery placement – done asleep● Programming done by the neurologists

○ Usually 3-4 weeks after lead implantation

○ Initial session is done off medication and is a long appointment

○ Multiple sessions are needed to fine tune the initial setting

DBS Procedure : Stage One, Lead Placement

Often done awakeFrame based or Frameless

Frame based – Imaging/Planning done the day of surgeryFrameless - Imaging and planning done before surgery

Confirmatory tests for lead placementMicroelectrode recordingTest stimulationIntra-operative imaging (MRI or CT)

Operative time (Bilateral) dependent on technique and operator

Admit to hospital over night – D/C next day

DBS Procedure : Stage Two, IPG Placement

Done under Anesthesia

Approximately 1 hour or less

Outpatient procedure

IPG in chest or abdomen

● Subthalamic Nucleus (STN)

○ Usually lower medication more than other targets

● Globus Pallidus, internal segment (GPi)

○ Unilateral surgery has more bilateral effects

● Ventral Intermediate nucleus (Vim)

○ Useful for TPPD with medication resistance

DBS Targets

Bilateral STN

Bilateral GPi

DBS Complications

Lead Migration/Breakage (1-3%) <1%Usually due severe trauma or twisting of the cables

Infection (3-5%) 2%Pulse generator is more common than “brain lead”

Hemorrhage - Blood clot (2%) <1%Most are insignificant found on postop imaging

DBS Expectations

Deep Brain Stimulation is NOT a cure

Tremor control does not mean tremor arrest in every case

Parkinson’s Disease symptoms that are improved are not completely arrestedtremor, bradykinesia, dyskinesia, rigidity

expect your best “on” time to be the majority of your day

DBS does not replace the use of medication

Dystonia improvement is better in large muscle groups

Conclusions

Surgery for PD is not experimental – based on real data and controlled trials

Surgery for PD is not a cure

The current approved methods are not mutually exclusive and not interchangeable

Each surgical intervention has its place

No surgical procedure is without complication

Seek experienced teams when considering surgery