Tacoma Valley Oncology Centers staffs will be attending the 2022 RSS Scientific Meeting on March 4th – 6th, 2022

Tacoma Valley Oncology Centers staffs will be attending the 2022 RSS Scientific Meeting on March 4th – 6th, 2022. The meeting will be located inside the Omni La Costa in Carlsbad, California.

This past summer, Tacoma Valley Oncology Centers hosted 4 junior research interns. Our junior research interns worked with our Radiation Oncologists and Nursing Manager on a research project involving Gamma Knife Stereotactic Radiosurgery treatment for Essential and Parkinsonian Tremor. They documented their evaluation which was submitted to the 2022 RSS Scientific Meeting. Below is their abstract that was accepted as a Poster to be presented at the meeting. All Poster authors will have the opportunity to provide an overview of their Poster during a scheduled time at the Poster Viewing Question & Answer Session during the Evening Reception from 5:00pm – 6:30pm PST on Friday, March 4th, 2022. We are very excited to see their hard work showcased!

Evaluation of Functional Outcomes in Gamma Knife Stereotactic Radiosurgery Treatment of Essential and Parkinsonian Tremor – A Private Institution Evaluation

D. Dunham, C. Cuthbert, N. Tyroum, H C. Wang, V. Wang, H L Wang, A. Pittier
Tacoma Valley Radiation Oncology Centers, Tacoma, WA, United States of America

Background: Our institution has previously reported on effectiveness and side effects of Gamma Knife Thalomotomy (GKT) for treatment resistant essential tremor(ET) and Parkinsonian tremor(PT).

Objective: Examine the functional outcomes and side effect profile of patients with Essential and Parkinsonian tremor, resistant to medical therapy, treated with GKT.

Methods: Fifteen-year review of our experience with medically refractory patients treated with GKT for disabling ET and PT. Previous treatments included DBS (1/91) and medications (58/91). Utilizing the Leksell treatment planning system, gamma knife was utilized to target the ventralis inter-medius (VIM), target dose ranged from 125-130Cy, utilizing a single 4mm shot. Effectiveness of therapy and evaluation of side effects was evaluated utilizing the Archimedes spiral test, in combination with patient follow ups.

Results: Complete resolution or significant improvement of tremor symptoms occurred in 85% of patients (77/91) at an average of 6 months post treatment. Archimedes tremor score pre and post op was utilized for analysis of therapeutic benefit. Median post-operative follow-up for evaluation was 16 months (duration 1-64). Side effect symptoms were evaluated clinically and radiographically utilizing MRI. Radiographically confirmed edema was noted on the side of treatment in 15% of patients (14/91). Major side effects included extremity weakness in 13% of patients. Unsteady gait developed in 5% (5/91), with 2% requiring a cane or wheel chair. Visual change in 2% (2/91), this manifested as blurriness. Verbal change 1% (1/91) manifested as expressive aphasia.

Conclusion: Gamma Knife Thalamotmy provides effective relief from tremors, comparable to that of DBS and RF. Persistent side effects were noted in 15% of patients, of which 50% diminished in time.