Kazuhiro Yamanaka

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UNLABELLED We evaluated the diagnostic accuracy of PET with l-methyl-(11)C-methionine ((11)C-MET) for the differentiation of recurrent brain tumors from radiation necrosis. METHODS Seventy-seven patients who had been previously treated with radiotherapy after primary treatment for metastatic brain tumor (n=51) or glioma (n=26) were studied to clarify the(More)
OBJECTIVE We evaluated the effectiveness of gamma knife radiosurgery in the treatment of nonfunctioning pituitary adenomas. METHODS Between January 1994 and December 1999, we treated 34 patients with nonfunctioning pituitary adenomas. Thirty-one of these patients were followed for more than 30 months. Their mean age was 52.9 years. All patients underwent(More)
BACKGROUND We aimed to examine whether stereotactic radiosurgery without whole-brain radiotherapy (WBRT) as the initial treatment for patients with five to ten brain metastases is non-inferior to that for patients with two to four brain metastases in terms of overall survival. METHODS This prospective observational study enrolled patients with one to ten(More)
We evaluated the endocrinological outcomes of gamma knife radiosurgery (GKS) for the treatment of growth hormone (GH)-producing pituitary adenomas. Twenty-six patients treated with GKS (median treatment [tumour] volume: 0.8 mL; median marginal radiation dose: 20Gy) were followed for a median of 84 months. "Disease remission" was defined as either nadir(More)
OBJECTIVE We report on the efficacy of gamma knife radiosurgery for cavernous sinus meningiomas. METHODS Between January 1994 and December 1999, we used gamma knife radiosurgery for the treatment of 43 patients with cavernous sinus meningiomas. Forty-two patients were followed up for a mean of 49.4 months (range, 18-84 mo). The patients' average age was(More)
OBJECT In this study the authors examined how to differentiate radiation necrosis from recurrent metastatic brain tumor following stereotactic radiosurgery by using positron emission tomography (PET) with L-[methyl-11C]methionine (MET). METHODS In 21 adult patients with suspected recurrent metastatic brain tumor or radiation injury, MET-PET scans were(More)
UNLABELLED The treatment of acoustic neuromas has been improved by advancements in microsurgical techniques and in radiosurgery. To further elucidate the degree of clinical improvement, we evaluated the treatment results of a combination of surgery and radiosurgery for large acoustic neuromas. METHODS From January 1994 through December 2000, we treated 14(More)
BACKGROUND We evaluated results of resection surgery followed by boost radiosurgery for the treatment of brain metastases. METHODS We treated 21 patients (13 male, 8 female) with surgical resection (subtotal or total) followed by boost radiosurgery. The mean patient age was 61 years (range, 41-80 years); supratentorial lesions were treated in 12 patients,(More)
OBJECT Following stereotactic radiosurgery (SRS), we examined how to differentiate radiation necrosis from recurrent malignant glioma using positron emission tomography (PET) with 11C-methionine (Met). METHODS Met-PET scans were obtained from 11 adult cases of recurrent malignant glioma or radiation injury, suspected on the basis of magnetic resonance(More)
OBJECT In this study, the authors evaluate the long-term results after Gamma Knife radiosurgery of cranial base meningiomas. This study is a follow-up to their previously published report on the early results. METHODS Between January 1994 and December 2001, the authors treated benign cranial base meningiomas in 108 patients using low-dose Gamma Knife(More)