The covering problem of a three dimensional body using different radii spheres is considered. motivating application – the treatment planning Gamma Knife radiosurgery briefly discussed. We approach only by geometric point view, that is, given set and body, objective to cover smallest possible number spheres, regardless dosage issue. In order solve this mathematical programming problem, we consi...

Rotating gamma systems (RGSs), GammaART-6000, and its Chinese equivalents, such as OUR and MASEP, etc., are new radiosurgery systems that use rotating 60Co sources instead of the 201 static sources (Leksell gamma knife, LGK). The rotating sources of RGSs simulate an infinite number of beams and promote extremely high target to surface dose ratios. However, the results of Monte Carlo in this stu...

A 43-year-old female was treated with gamma knife radiosurgery (GKS) for right frontal arteriovenous malformation (AVM) manifesting as absence seizures. Complete nidus obliteration was confirmed on angiography 4 years after GKS. However, she experienced recurrence of her previous seizures and delayed hemorrhage occurred within the treated nidus, despite absence of abnormalities by repeated angi...

We present results of investigations of the clinical significance of variations in the value of the 4-mm-collimator output factor, OF(4/18). Changes in treatment volume, dose-volume histograms (DVHs), and isodose distributions were studied, by varying OF(4/18) up to 20%. The variations were performed on a sample of clinical patient treatment plans for which the 4 mm collimator was used. Althoug...

A 50-year-old man was treated with stereotactic gamma knife radiosurgery for an incidentally detected small callosal arteriovenous malformation (AVM) with stenosis of the main draining pathway. He suffered two episodes of intraventricular hemorrhage at 4 and 14 weeks after the radiosurgery. Radiological studies demonstrated that the anterior portion of the draining system including a varix, whi...

Since its introduction by Leksell, Gamma Knife radiosurgery (GKRS) has become increasingly popular as a management approach for patients diagnosed with trigeminal neuralgia (TN). For this reason, we performed a modern review of the literature analyzing the efficacy of GKRS in the treatment of patients who suffer from TN. For patients with medically refractory forms of the condition, GKRS has pr...

INTRODUCTION The accuracy of radiation delivery is increasingly important as radiotherapy technology continues to develop. The goal of this study was to evaluate intrafractional motion during intracranial radiosurgery and the relationship between motion change and treatment time. METHODS AND MATERIALS A total of 50 treatment records with 5988 images, all acquired during treatments with the Cy...

Brain stem arteriovenous malformations (AVMs) are rare and their clinical management is controversial. A location in highly eloquent areas and a greater risk of radionecrosis are both serious issues for radiosurgery of this entity. We report a case of a pontine AVM treated successfully with gamma knife therapy. At 3 years angiographic follow-up, imaging demonstrated complete thrombosis and ther...

PURPOSE To evaluate an automated treatment planning system for gamma knife radiosurgery. This planning system was developed in our clinic and is now in routine clinical use. The system simultaneously optimizes the shot sizes, locations, and weights. It also guides the user in selecting the total number of radiation shots. METHODS AND MATERIALS We assessed the clinical significance of the auto...