L. Dade Lunsford

The History of Movement Disorder Brain Surgery

The first surgical procedures for abnormal movement disorders began in the 1930s, when surgeons first proposed ablative techniques of the caudate nucleus or transection of motor (pyramidal) pathways to reduce involuntary movements in patients with Parkinsons related tremor. During the 50-year interval between 1945 and 1995, the development of precise intracranial guiding devices, brain maps, and advanced imaging led to the refinement of appropriate deep brain targets affecting extrapyramidal pathways. Lesional surgery and subsequent neuroaugmentation using deep brain stimulation extended the role of deep brain surgery for a wider group of patients with tremor, rigidity, dyskinesia, and other involuntary movement disorders. Stereotactic radiosurgery has had wide application for tremor. The history of movement disorder surgery reads like a whos who of brilliant and resourceful surgeons who pushed the frontiers of neurosurgery. Even today, practitioners of functional brain surgery are among the most innovative practicing neurosurgeons.

Stereotactic Radiosurgery in the Multimodality Management of Residual or Recurrent Glioblastoma Multiforme

Management options for residual or recurrent glioblastoma multiforme (GBM) are limited despite advances in surgical, chemotherapeutic, and radiotherapeutic techniques. Stereotactic radiosurgery (SRS) is often beneficial in such cases providing improved survival of patients, but still remains underutilized as part of the multimodality management of malignant gliomas. During the last 20 years, 297 patients with histologically proven residual or recurrent GBM underwent Gamma Knife surgery in the University of Pittsburgh. Retrospective analysis of outcomes revealed median survival after initial diagnosis of 18 months, and 1- and 2-year survival rates of 72.5 and 29.5%, respectively. Median survival from the time of SRS was 9 months. The use of modified RPA (recursive partitioning analysis) classification demonstrated superior survival in our series in comparison with historical data. Important prognostic variables include tumor volume <14 cm3, marginal radiation dose of ≥15 Gy, and younger age of the patients (<60 years). Adverse radiation effects (ARE) were noted in 23% of cases and were mainly controlled with corticosteroids. Combining SRS with bevacizumab resulted in further improvement of the overall and progression-free survival and decreased incidence of ARE. Nevertheless, for future application of SRS in patients with GBM, evaluation of its efficacy in a well-designed prospective controlled clinical trials seems mandatory.

Chapter 18 – Treatment of Brain Metastases from Ovarian and Endometrial Carcinomas Using Stereotactic Radiosurgery

Brain metastases from ovarian and endometrial carcinomas are rare but the incidence appears to be increasing in the setting of improved systemic therapies and prolonged survivals. Whole brain radiation therapy (WBRT) has long been a reflexive treatment for patients with brain metastases. Stereotactic radiosurgery (SRS) has evolved into a highly individualized, safe, and effective approach for the treatment of intracranial tumors. Concerns over the toxicities of WBRT have arisen with improved quality of life and longer survivals experienced by many cancer patients. However, due to their limited numbers, patients harboring brain metastases from these histologies have not been meaningfully incorporated in the larger, prospective SRS studies that serve as the framework that guides most clinicians. All the available data involves small, retrospective case series, with most patients treated on Gamma Knife units. From these low quality data, SRS appears to an appropriate treatment modality for patients harboring brain metastases from ovarian or endometrial carcinomas. Extrapolation of data from high-quality, prospective clinical trials that do not include patients with ovarian or endometrial carcinomas support the use of upfront SRS followed by surveillance and salvage SRS as necessary. Withholding WBRT except in the setting of carcinomatous meningitis or miliary brain disease seems not to negatively affect survival and sustained neurological function, and appears to protect against cognitive dysfunction. Further study of patients with ovarian or endometrial brain metastases is necessary to confirm this extrapolation and should be facilitated by combining data within prospective registries from large consortia studying these patients (ie, North American Gamma Knife Consortium).