Retrospective analysis of imaging techniques for treatment planning and monitoring of obliteration for gamma knife treatment of cerebral arteriovenous malformation.

Background: It has been well established that Gamma Knife radiosurgery (GKS) is an effective treatment for brain arteriovenous malformations (AVMs).

Objective: To evaluate complete obliteration rates for magnetic resonance imaging (MRI)-based GKS treatment planning performed with and without angiography and to conduct a preliminary assessment of the utility of using pulsed arterial spin labeling (PASL) magnetic resonance (MR) perfusion imaging to confirm complete obliteration.

Methods: Forty-six patients were identified who had undergone GKS without embolization with a minimum follow-up of 2 years.

Gamma knife radiosurgery in the treatment of tumor-related facial pain.

Background: Intracranial neoplasms can cause pain similar to trigeminal neuralgia. Literature regarding radiosurgery for this is limited. We present a retrospective review of patients with tumor-related facial pain from benign lesions treated with gamma knife radiosurgery (GKRS) at Wake Forest University.

Toxicity of gamma knife radiosurgery in the treatment of intracranial tumors in patients with collagen vascular diseases or multiple sclerosis.

Purpose: To assess toxicity in patients with either a collagen vascular disease (CVD) or multiple sclerosis (MS) treated with intracranial radiosurgery.

Methods And Materials: Between January 2004 and April 2009, 6 patients with MS and 14 patients with a CVD were treated with Gamma Knife radiosurgery (GKRS) for intracranial tumors. Treated lesions included 15 total brain metastases in 7 patients, 11 benign brain tumors, 1 low grade glioma, and 1 cavernous malformation.

Cavity-directed radiosurgery as adjuvant therapy after resection of a brain metastasis.

Object: As a strategy to delay or avoid whole-brain radiotherapy (WBRT) after resection of a brain metastasis, the authors used high-resolution MR imaging and cavity-directed radiosurgery for the detection and treatment of further metastases.

Methods: Between April 2001 and October 2009, 112 resection cavities in 106 patients with no prior WBRT were treated using radiosurgery directed to the tumor cavity and for any synchronous brain metastases detected on high-resolution MR imaging at the time of radiosurgical planning. A median dose of 17 Gy to the 50% isodose line was prescribed to the gross tumor volume, defined as the rim of enhancement around the resection cavity.

Repeat gamma knife radiosurgery for trigeminal neuralgia.

Purpose: Repeat gamma knife stereotactic radiosurgery (GKRS) for recurrent or persistent trigeminal neuralgia induces an additional response but at the expense of an increased incidence of facial numbness. The present series summarized the results of a repeat treatment series at Wake Forest University Baptist Medical Center, including a multivariate analysis of the data to identify the prognostic factors for treatment success and toxicity.

Methods And Materials: Between January 1999 and December 2007, 37 patients underwent a second GKRS application because of treatment failure after a first GKRS treatment.

Use of 3.0-T MRI for stereotactic radiosurgery planning for treatment of brain metastases: a single-institution retrospective review.

Purpose: To investigate the efficacy of 3.0-T magnetic resonance imaging (MRI) for detecting brain metastases for stereotactic radiosurgery (SRS) planning.

Methods And Materials: All adult patients scheduled for SRS treatment for brain metastases at our institution between October 2005 and January 2008 were eligible for analysis.

The Hug-Kellerer equation as the universal cell survival curve.

The Hug-Kellerer (H-K) equation is one of the earliest proposed radiation cell survival curves. We examine this equation in view of the recent perceived need for a universal cell survival curve which would be applicable to single radiation fractions at high doses. We derive relationships between the three parameters of the H-K equation and the parameters alpha and beta of the linear-quadratic equation.

Alternative dose for choroidal melanoma treated with an iodine-125 radioactive plaque: a single-institution retrospective study.

Purpose: The Collaborative Ocular Melanoma Study (COMS) established iodine-125 plaque brachytherapy as an accepted standard treatment for medium-size choroidal melanoma. In the COMS, the prescription dose was 85 Gy. This is a retrospective review of our outcomes in patients treated with lower doses than those used in the COMS.

Optically guided linac radiosurgery with a Leksell head frame as an adjunct to Gamma Knife treatment.

Because of geometrical limitations in the helmet of the Leksell Gamma Knife(Elekta Corp., Atlanta, GA, USA) certain regions within the cranium cannot be targeted for treatment. We describe a method by which lesions in these regions can be treated with the Varian-Zmed stereotactic radiosurgery system utilizing an infrared optical positioning system attached to a Leksell head frame.

Gamma Knife surgery targeting the resection cavity of brain metastasis that has progressed after whole-brain radiotherapy.

Object: Salvage treatment of large, symptomatic brain metastases after failure of whole-brain radiotherapy (WBRT) remains challenging. When these lesions require resection, there are few options to lower expected rates of local recurrence at the resection cavity margin. The authors describe their experience in using Gamma Knife surgery (GKS) to target the resection cavity in patients whose tumors had progressed after WBRT.

Does dose rate affect efficacy? The outcomes of 256 gamma knife surgery procedures for trigeminal neuralgia and other types of facial pain as they relate to the half-life of cobalt.

Object: Gamma Knife surgery (GKS) is a treatment option for patients with refractory typical trigeminal neuralgia (TN), TN with atypical features, and atypical types of facial pain. The Gamma Knife's 201 60Co sources decay with a half-life of 5.26 years.

The use of a Leksell-BRW adapter for linac radiosurgery as an adjunct to Gamma Knife treatment.

We have investigated the use of an adapter that permits the use of a Leksell coordinate frame with a linear accelerator stereotactic radiosurgery system based on the Brown-Robert-Wells (BRW) design. This device is useful when lesions that are planned for treatment on a Leksell Gamma Knife system are found to be inaccessible to the Gamma Knife. We have found that with this device objects within a head phantom can be targeted by the linear accelerator within an accuracy of approximately 1 mm.