C-methionine-PET-guided Gamma Knife radiosurgery boost as adjuvant treatment for newly diagnosed glioblastomas.

Background: The most common glial tumor is the glioblastoma, and the prognosis remains dismal despite a multimodal therapeutic approach. The role of radiosurgery for the treatment of glioblastomas has been evaluated in several studies with some benefit at the recurrent stage. We evaluate the results of the protocol administered at the Gamma Knife unit administering radiosurgery as a boost to metabolic active parts of the tumor after the patient had completed traditional external beam radiotherapy (XBRT) as part of the Stupp protocol for high-grade gliomas.

Definition of the key target volume in radiosurgical management of arteriovenous malformations: a new dynamic concept based on angiographic circulation time.

Object: The cumulative experience worldwide indicates complete radiosurgical obliteration rates of brain arteriovenous malformations (AVMs) ranging from 35 to 90%. The purpose of this study was to propose a strategy to increase the obliteration rate for AVMs through the dynamic definition of the key target volume (KTV).

Methods: A prospective series of patients harboring an AVM was assessed using digital subtraction angiography in which a digital counter was used to measure the several stages of the frame-by-frame circulation time.

[Traumatic dissection of extracranial internal carotid artery with middle cerebral artery stroke: imaging diagnosis].

Cervical carotid artery dissections (CCAD) are common in young adults with a mean age of 44 years and may account for as many as 20% of strokes in patients younger than 30 years. Trauma and primary diseases of the arterial wall such as fibromuscular dysplasia are the main predisposing factors. Some CCAD cases are diagnosed solely on clinical history and physical examination, and even imaging tools such as helical/multi-slice computed tomography (CT) and magnetic resonance imaging (MRI) sometimes are not sufficient to reach a diagnosis.

Stereotactic noninvasive volume measurement compared with geometric measurement for indications and evaluation of gamma knife treatment.

Object: Volume estimation is one of the most important criteria in the evaluation and follow up of radiosurgical treatments and outcomes; however, several limitations are involved in the calculation estimation of target volumes.

Methods: Retrospective and prospective studies were conducted to evaluate the efficacy of a new noninvasive stereotactic method when it is compared with geometric volume calculation of intracranial tumors for planning stereotactic radiosurgery treatment as well as for follow up and outcome evaluation. Two equations were created that permit comparison of the calculated and measured volumes.

Endovascular treatment of a transverse-sigmoid sinus aneurysm presenting as pulsatile tinnitus. Case report.

The authors report on the case of a 38-year-old woman who had experienced incapacitating pulsatile tinnitus in the left ear for 6 months. Angiographic studies revealed a wide-necked venous aneurysm of the left transverse-sigmoid sinus. Solitary stent placement across the aneurysm neck resulted in a slight modification in the lesion's characteristics.

Primary empty sella syndrome: the role of visual system herniation.

Background: It has been traditionally accepted that ophthalmologic alterations in cases of primary empty sella syndrome are caused by the herniation of the visual system in the pituitary fossa, but this cannot be stated categorically.

Methods: Two female patients with primary empty sella syndrome and visual field defects were included in this series. The peculiarity of these cases was that in neither of them was there an evident herniation of the visual system.