Leksell Stereotactic Radiosurgery for Cavernous Malformations.

Cavernous malformations (CM) represent a distinct subgroup of brain vascular malformations that are characterized by small sinusoidal vascular channels with hyaline degeneration and old blood pigments. Because of the increasing availability of magnetic resonance imaging (MRI) they are detected much more frequently in the present era. CM may be solitary or found in the context of a familial variant that results in an increasing number of CM developing as the patient ages. Because of the variable risk of subacute bleeding, their management options have been controversial. The annual risk of an incidentally detected CM bleeding is <0.5% each year. Leksell radiosurgery is used for a subgroup of patients who have repeatedly bled. In general, CM best considered for stereotactic radiosurgery are deep seated and do not pre-sent to a pial or ependymal surface where microsurgical corridors for removal are feasible. When radiosurgery is used for patients at high risk for both re-bleeding as well as microsurgical resection, the risk of bleeding can be reduced from as high as 33% each year to <0.5% each year after a 2-year latency interval. The target lies within the hemosiderin rim detected during the MRI that is part of planning. Marginal doses are significantly less than those used for angiographically visible arteriovenous malformations.

Salvage Leksell Stereotactic Radiosurgery for Malignant Gliomas.

The outcome of patients with malignant gliomas has not substantially improved, even with advances in imaging, neurosurgery, molecular subtyping, and radiation, and newer oncologic options. Maximal safe resection when feasible remains the initial treatment of choice for most malignant gliomas. These tumors often recur and require additional therapy to control the tumor growth. Leksell stereotactic radiosurgery (SRS) is offered as salvage therapy in patients with recurrent or residual malignant gliomas. SRS is well tolerated and is associated with a relatively low risk of adverse radiation effects in malignant glial tumor patients who otherwise have relatively few options. SRS allows the surgeon more flexibility in terms of surgical options and may enhance quality of life for patients postoperatively. Although randomized controlled studies are lacking in the use of salvage SRS after the failure of initial standard of care management, preliminary data suggest that radiosurgery improves tumor control and overall survival for patients with recurrent malignant gliomas.

Gamma Knife Stereotactic Radiosurgery for Trigeminal Neuralgia Caused by a Developmental Venous Anomaly.

Background: Trigeminal neuralgia (TN) is mostly caused by vascular compression of the nerve's root entry zone due to an ectatic artery. Rarer causes include compression from tumors, vascular malformations or multiple sclerosis plaques. Developmental venous anomalies (DVAs) are benign, aberrantly appearing venous structures that drain normal cerebral tissue. DVAs are a rare etiology of TN. The management of TN caused by a DVA is controversial as disruption of the DVA can be catastrophic. Methods: We report a case of a young man with severe medically refractory TN related to a brachium pontis DVA who was successfully treated by gamma knife stereotactic radiosurgery (GKSR) to the trigeminal nerve. Results: Within 2 weeks of GKSR, the patient reported experiencing 60% pain relief; 5 years postoperatively, he remains completely pain free with some mild sensory loss in the V2 and V3 areas. Conclusions: GKSR has an established role in the management of TN. This is the first reported case of using GKSR to treat TN caused by a DVA. In the setting of a DVA, GKSR should be an initial consideration for TN therapy after medical failure because of the high surgical risk related to disrupting the DVA. © 2015 S. Karger AG, Basel.

Future perspectives on brain metastasis management.

Brain metastases are the most common intracranial tumors encountered by physicians. Historically, the mainstays of therapy were limited to surgery and whole brain radiation. Surgery is typically reserved for safely accessible and symptomatic tumors in patients well enough to tolerate a procedure. Whole-brain radiation therapy has proven to have limited efficacy and concerns have arisen regarding its toxicity. Advances in the treatment of systemic cancers have yielded improved long-term survival and quality of life for patients. To parallel these efforts in systemic treatment, continual improvement of the treatment of brain metastases is a must. The last two decades have seen a paradigm shift in the thinking about metastatic brain tumor treatment as a result of the advent of stereotactic radiosurgery. Radiosurgery has proven to be an efficacious, minimally invasive, and highly selective treatment for metastatic brain tumors. In this review, we discuss the evolution of metastatic brain tumor management, the appropriately diminished role for reflexive whole brain radiation, and the growing importance of stereotactic radiosurgery as an upfront treatment modality in conjunction with surgery and subsequent salvage radiosurgery.