Gamma knife thalamotomy for Parkinson disease and essential tremor: a prospective multicenter study.

Background: No prospective study of gamma knife thalamotomy for intractable tremor has previously been reported.

Objective: To clarify the safety and optimally effective conditions for performing unilateral gamma knife (GK) thalamotomy for tremors of Parkinson disease (PD) and essential tremor (ET), a systematic postirradiation 24-month follow-up study was conducted at 6 institutions. We present the results of this multicenter collaborative trial.

Primary Ewing's sarcoma of the orbit: case report.

A 22-year-old man presented with tenderness and swelling of the left lateral part of the orbit. Computed tomography revealed a left intraorbital mass measuring 3 cm x 3 cm involving the left lateral wall of the orbit and the greater wing of the left sphenoid bone. Magnetic resonance imaging revealed that the intraorbital mass was extraneuroaxial.

Ultrastructural and immunohistochemical study of an adult case of chordoid meningioma.

A 64-year-old male patient presented with generalized convulsions. Magnetic resonance imaging revealed a large meningeal tumor with some cysts in the right frontal region. Surgical resections were performed three times, and local radiation therapy was administered twice over a period of 8 years for the treatment of tumor recurrences.

Treatment of functional disorders with gamma knife thalamotomy.

Gamma knife (GK) thalamotomy for functional disorders, primarily Parkinson disease and central pain, are described herein. The goal was to extend our present indications for selective thalamotomy. Our target for tremor surgery is about 45% of the thalamic length.

From selective thalamotomy with microrecording to gamma thalamotomy for movement disorders.

A theoretical and practical process from microrecording-guided thalamotomy to gamma knife thalamotomy was briefly reviewed. Based on our own experiences of selective thalamotomy with microrecording, we are trying to apply gamma knife to the treatment of movement disorders. An important technical problem is how to determine the exact thalamic target.

Neurophysiological evaluation of the optimum target in gamma thalamotomy: indirect evidence.

Gamma thalamotomy has been useful for the treatment of Parkinson's disease and other movement disorders, but it has disadvantages, such as a delayed clinical effect after irradiation and the inaccuracy of targeting because depth recording is not available. Therefore, we sought to determine the optimum target in gamma thalamotomy based on the results of conventional selective thalamotomy with reference to the AC-PC line. To obtain indirect support for the appropriateness of the optimum target, we performed depth recording around the region of the estimated optimum target based on the results of conventional thalamotomy.

Gamma knife thalamotomy for movement disorders: evaluation of the thalamic lesion and clinical results.

Object: The authors studied the effects of gamma knife thalamotomy (GKT) on Parkinson disease-related tremor and essential tremor before and after reloading of radioactive cobalt.

Methods: Based on experience in stereotactic thalamotomy aided by depth microrecording, the target was located at the lateral border of the thalamic ventralis intermedius nucleus (VIM). For more precise targeting, the percentage representation of the thalamic VIM in relation to the entire thalamic length is useful.

Forty years with Professor Narabayashi.

Professor Hirotaro Narabayashi (1922-2001) was the founder of stereotactic neurosurgery in Japan and one of the early great world pioneers in this field. He constructed his first stereotactic apparatus in 1949 and performed his first pallidotomy in 1951, unaware of the similar work of others outside postwar Japan. His neurological clinic, which opened in Tokyo in 1957, became an international center for stereotaxy for more than 40 years.

Thalamic lesions produced by gamma thalamotomy for movement disorders.

Object: The treatment of Parkinson disease and other kinds of involuntary movement by gamma knife radiosurgery (GKS) is presented. This is an extension of previous work. The clinical course and thalamic lesions were the main factors examined.

Hemorrhage risks and obliteration rates of arteriovenous malformations after gamma knife radiosurgery.

Object: The purpose of this study was to analyze the risk of hemorrhage and the obliteration rate after treatment of patients with arteriovenous malformations (AVMs).

Methods: Between 1991 and 1995, 115 patients were treated using gamma knife radiosurgery (GKS). Surgical planning was based on angiograms and three-dimensional images.

Barbarian medicine in feudal Japan.

THE FIRST EUROPEANS to discover Japan were Portuguese traders who arrived in 1542. Fifteen years later, the Portuguese Jesuit priest and surgeon Luis De Almeida (1525-1583) founded the first Western hospital in Japan, for the care of lepers, syphilitics, and orphans. Because the hospital had a negative influence on the spread of Christianity, the Jesuits closed it in 1586.