Minim Invasive Neurosurg 2011; 54(05/06): 286-289
DOI: 10.1055/s-0031-1297987
Technical Note
© Georg Thieme Verlag KG Stuttgart · New York

“Donut’s Shape” Radiosurgical Treatment Planning for Large Cystic Metastatic Brain Tumors

M. Hayashi
Department of Neurosurgery, Neurological Institute, Tokyo Women’s Medical University, Tokyo, Japan
Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, Tokyo, Japan
,
M. Chernov
Department of Neurosurgery, Neurological Institute, Tokyo Women’s Medical University, Tokyo, Japan
Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, Tokyo, Japan
,
N. Tamura
Department of Neurosurgery, Neurological Institute, Tokyo Women’s Medical University, Tokyo, Japan
,
M. Tamura
Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, Tokyo, Japan
,
M. Izawa
Department of Neurosurgery, Neurological Institute, Tokyo Women’s Medical University, Tokyo, Japan
,
Y. Muragaki
Department of Neurosurgery, Neurological Institute, Tokyo Women’s Medical University, Tokyo, Japan
Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, Tokyo, Japan
,
H. Iseki
Department of Neurosurgery, Neurological Institute, Tokyo Women’s Medical University, Tokyo, Japan
Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, Tokyo, Japan
,
Y. Okada
Department of Neurosurgery, Neurological Institute, Tokyo Women’s Medical University, Tokyo, Japan
› Author Affiliations
Further Information

Publication History

Publication Date:
25 January 2012 (online)

Abstract

Background

Radiosurgical management of large cystic metastatic brain tumors represents a significant challenge. Nevertheless, modified dose planning has shown beneficial results in such cases.

Method and Results:

“Donut’s shape” radiosurgical treatment planning is based on the chain-like application of multiple, small-sized isocenters for selective coverage of the contrast-enhancing tumor capsule and minimal irradiation of the central cystic area. Such an approach was used for the management of large cystic intracranial metastases, which were not accompanied by a significant mass effect and did not require immediate volume reduction. Treatment was done using Leksell Gamma Knife model C with automatic positioning system. The majority of treated lesions showed significant shrinkage after radiosurgery and no major complications were met.

Conclusion:

Large cystic metastatic brain tumors may be successfully treated with gamma knife radiosurgery alone using the proposed “donut’s shape” dose planning with coverage of the contrast-enhancing tumor capsule by multiple small-sized isocenters.