Stereotactic Radiosurgery of the Brain Using the First United States 201 Cobalt-60 Source Gamma Knife

Abstract The first United States 201 cobalt-60 source gamma knife for stereotactic radiosurgery of brain tumors and arteriovenous malformations became operational at the University of Pittsburgh on August 14, 1987. Four and one-half years of intensive planning, regulatory agency review, and analysis of published results preceded the first radiosurgical procedure. Installation of this 18,000-kg device and loading of the 201 cobalt-60 sources posed major challenges in engineering, architecture, and radiophysics. In the first 4 months of operation, we treated 52 patients (29 with arteriovenous malformations, 19 with extra-axial neoplasms of the skull base, and 4 with intra-axial malignant tumors). Most patients either had lesions considered “inoperable” or had residual lesions after attempted surgical resection. Neither surgical mortality nor significant morbidity was associated with gamma knife radiosurgery. As compared with treatment by conventional intracranial surgery (craniotomy), the average length of stay for radiosurgery was reduced by 4 to 14 days, and hospital charges were reduced by as much as 65%. Based on both the previously published results of treatment of more than 2,000 patients worldwide and on our initial clinical experience, we believe that gamma knife stereotactic radiosurgery is a therapeutically effective and economically sound alternative to more conventional neurosurgical procedures, in selected cases.

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Stereotactic radiosurgery of intracranial arteriovenous malformations and the use of the K index in determining treatment dose

Neurosurgical FOCUS ◽

10.3171/2014.7.focus14157 ◽

2014 ◽

Vol 37 (3) ◽

pp. E15 ◽

Cited By ~ 4

Author(s):

Symeon Missios ◽

Kimon Bekelis ◽

Gasser Al-Shyal ◽

Peter A. Rasmussen ◽

Gene H. Barnett

Keyword(s):

Stereotactic Radiosurgery ◽

Gamma Knife ◽

Arteriovenous Malformations ◽

Univariate Analysis ◽

Gamma Knife Radiosurgery ◽

Maximum Diameter ◽

Obliteration Rate ◽

K Index ◽

Kaplan Meier ◽

Cerebral Avms

Object The appropriate dose during stereotactic radiosurgery (SRS) of cerebral arteriovenous malformations (AVMs) remains a matter of debate. In the present study, the authors retrospectively evaluated the association of using a prescribed dose calculated utilizing the K index with the obliteration rate of cerebral AVMs after SRS. Methods The authors performed a retrospective analysis of the Cleveland Clinic SRS database. All patients undergoing Gamma Knife radiosurgery for cerebral AVMs from 1997 to 2010 were selected. Regression techniques and Kaplan-Meier analyses were used to investigate the effect of divergence from the optimal K index dose on the rate of AVM obliteration. Results In the study period 152 patients (mean age 43.6 years; 53.9% of treatments were performed in females) underwent 165 Gamma Knife radiosurgery treatments for AVMs. In a univariate analysis Spetzler-Martin grade (OR 0.63 [95% CI 0.42–0.93]), higher AVM score (OR 0.43 [95% CI 0.27–0.70]), larger AVM volume (OR 0.88 [95% CI 0.82–0.94]), and higher maximum diameter (OR 0.56 [95% CI 0.41–0.77]) were associated with a lower rate of AVM obliteration. Higher margin dose (OR 1.16 [95% CI 1.08–1.24]) and higher maximum dose (OR 1.08 [95% CI 1.04–1.13]) were associated with a higher obliteration rate. To further examine the effect of prescribed dose divergence from the calculated K index dose, cases were classified to groups depending on the AVM volume and dose variance from the ideal K index dose. Contingency tables and Kaplan-Meier curves were then created, and no significant differences in rates of obliteration were noted among the different groups. Conclusions Gamma Knife radiosurgery for cerebral AVMs remains an effective and safe treatment modality. Smaller AVMs may receive doses less than the calculated K index dose without an apparent effect on obliteration rates.

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Gamma knife radiosurgery for cerebral arteriovenous malformations in children/adolescents and adults. Part II: Differences in obliteration rates, treatment-obliteration intervals, and prognostic factors

Yearbook of Neurology and Neurosurgery ◽

10.1016/s0513-5117(08)70168-6 ◽

2007 ◽

Vol 2007 ◽

pp. 242

Author(s):

W.B. Gormley

Keyword(s):

Prognostic Factors ◽

Gamma Knife ◽

Arteriovenous Malformations ◽

Gamma Knife Radiosurgery ◽

Cerebral Arteriovenous Malformations ◽

Adolescents And Adults

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Gamma knife radiosurgery as a single treatment modality for large cerebral arteriovenous malformations

Journal of Neurosurgery ◽

10.3171/jns.2000.93.supplement_3.0113 ◽

2000 ◽

Vol 93 (supplement_3) ◽

pp. 113-119 ◽

Cited By ~ 82

Author(s):

D. Hung-Chi Pan ◽

Wan-Yuo Guo ◽

Wen-Yuh Chung ◽

Cheng-Ying Shiau ◽

Yue-Cune Chang ◽

...

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Radiation Treatment ◽

Gamma Knife Radiosurgery ◽

Consecutive Series ◽

Content Type ◽

Obliteration Rate ◽

Complete Obliteration ◽

Fine Print

Object. A consecutive series of 240 patients with arteriovenous malformations (AVMs) treated by gamma knife radiosurgery (GKS) between March 1993 and March 1999 was evaluated to assess the efficacy and safety of radiosurgery for cerebral AVMs larger than 10 cm3 in volume. Methods. Seventy-six patients (32%) had AVM nidus volumes of more than 10 cm3. During radiosurgery, targeting and delineation of AVM nidi were based on integrated stereotactic magnetic resonance (MR) imaging and x-ray angiography. The radiation treatment was performed using multiple small isocenters to improve conformity of the treatment volume. The mean dose inside the nidus was kept between 20 Gy and 24 Gy. The margin dose ranged between 15 to 18 Gy placed at the 55 to 60% isodose centers. Follow up ranged from 12 to 73 months. There was complete obliteration in 24 patients with an AVM volume of more than 10 cm3 and in 91 patients with an AVM volume of less than 10 cm3. The latency for complete obliteration in larger-volume AVMs was significantly longer. In Kaplan—Meier analysis, the complete obliteration rate in 40 months was 77% in AVMs with volumes between 10 to 15 cm3, as compared with 25% for AVMs with a volume of more than 15 cm3. In the latter, the obliteration rate had increased to 58% at 50 months. The follow-up MR images revealed that large-volume AVMs had higher incidences of postradiosurgical edema, petechiae, and hemorrhage. The bleeding rate before cure was 9.2% (seven of 76) for AVMs with a volume exceeding 10 cm3, and 1.8% (three of 164) for AVMs with a volume less than 10 cm3. Although focal edema was more frequently found in large AVMs, most of the cases were reversible. Permanent neurological complications were found in 3.9% (three of 76) of the patients with an AVM volume of more than 10 cm3, 3.8% (three of 80) of those with AVM volume of 3 to 10 cm3, and 2.4% (two of 84) of those with an AVM volume less than 3 cm3. These differences in complications rate were not significant. Conclusions. Recent improvement of radiosurgery in conjunction with stereotactic MR targeting and multiplanar dose planning has permitted the treatment of larger AVMs. It is suggested that gamma knife radiosurgery is effective for treating AVMs as large as 30 cm3 in volume with an acceptable risk.

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Factors related to complete occlusion of arteriovenous malformations after gamma knife radiosurgery

Journal of Neurosurgery ◽

10.3171/jns.2000.93.supplement_3.0096 ◽

2000 ◽

Vol 93 (supplement_3) ◽

pp. 96-101 ◽

Cited By ~ 67

Author(s):

Jong Hee Chang ◽

Jin Woo Chang ◽

Yong Gou Park ◽

Sang Sup Chung

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Gamma Knife Radiosurgery ◽

Maximum Diameter ◽

Content Type ◽

Complete Occlusion ◽

Factors Associated ◽

Martin Grade ◽

Fine Print

Object. The authors sought to evaluate the effects of gamma knife radiosurgery (GKS) on cerebral arteriovenous malformations (AVMs) and the factors associated with complete occlusion. Methods. A total of 301 radiosurgical procedures for 277 cerebral AVMs were performed between December 1988 and December 1999. Two hundred seventy-eight lesions in 254 patients who were treated with GKS from May 1992 to December 1999 were analyzed. Several clinical and radiological parameters were evaluated. Conclusions. The total obliteration rate for the cases with an adequate radiological follow up of more than 2 years was 78.9%. In multivariate analysis, maximum diameter, angiographically delineated shape of the AVM nidus, and the number of draining veins significantly influenced the result of radiosurgery. In addition, margin radiation dose, Spetzler—Martin grade, and the flow pattern of the AVM nidus also had some influence on the outcome. In addition to the size, topography, and radiosurgical parameters of AVMs, it would seem to be necessary to consider the angioarchitectural and hemodynamic aspects to select proper candidates for radiosurgery.

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