scholarly journals Gamma Knife Radiosurgery: An Overview of Physics, Chemistry, Biology and Neuro-medicine

1970 ◽  
Vol 28 (2) ◽  
pp. 100-112
Author(s):  
KMN Uddin ◽  
JN Islam
Keyword(s):  
Gamma Knife ◽  
Vascular Malformations ◽  
Gamma Knife Radiosurgery ◽  
High Energy ◽  
Quadratic Model ◽  
High Dose ◽  
Linear Quadratic ◽  
Treatment Unit ◽  
Stereotactic Technique ◽  
Living Tissues

The gamma knife is a highly specialized treatment unit thatprovides an advanced sophisticated stereotactic approachto treatment of tumour and vascular malformations withinthe internal structure of the head. The gamma knife deliversa single high dose of radiation emanating from 201 cobalt-60 unit sources. All 201 beam simultaneously intersect atthe same time in a pre-defined location. The treatmentplanning system for gamma knife radiosurgery has beendeveloped using nonlinear programming techniques. Thesystem optimizes the shot sizes, location and weights forgamma knife treatments. Open stereotactic technique in the1990’s was essential for the treatment of a number offunctional conditions and cystic space occupying lesions.It has an important part to play in the investigation oftumours and can help to increase the number which areaccessible to treatment. It can be employed to guide notonly solid instruments but also ionizing irradiation to “masslesion– targets”. It is just this combination of stereotacticguidance and narrow beam, high energy radiation toprecisely defined target, is the basis of gamma kniferadiosurgery . The topic on radiological physics presents abroad field, which includes physics of radiation therapy,diagnosis and nuclear medicine. The emphasis is on thebasic physical principles which form a common foundationfor these areas. Consequently, the topic provides both basicradiation physics, physical aspects of treatment planningand use of radiation beams. Some knowledge of the effectof ionizing radiation on living tissues is necessary, for thosewho wish to understand the nature of any treatment usingradiation and who also wish to inform patients about suchtreatment. The topic relates to the effects of radiation onvisible structures, in other words, cells and tissues. Theradiobiological knowledge described here has beendeveloped in relation to standard radiotherapy. Moreover,the linear quadratic model of cell killing is also applicablefor single dose irradiation.DOI: 10.3329/jbcps.v28i2.5370J Bangladesh Coll Phys Surg 2010; 28: 100-112

Gamma knife radiosurgery in patients with advanced breast cancer undergoing bone marrow transplant

2002 ◽  
Vol 97 ◽  
pp. 663-665 ◽  
Author(s):  
Kenneth J. Levin ◽  
Emad F. Youssef ◽  
Andrew E. Sloan ◽  
Rajiv Patel ◽  
Rana K. Zabad ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Advanced Breast Cancer ◽  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
High Dose Chemotherapy ◽  
Advanced Breast ◽  
High Dose ◽  
Initial Management ◽  
Content Type ◽  
Fine Print

Object. Recent studies have suggested a high incidence of cognitive deficits in patients undergoing high-dose chemotherapy, which appears to be dose related. Whole-brain radiotherapy (WBRT) has previously been associated with cognitive impairment. The authors attempted to use gamma knife radiosurgery (GKS) to delay or avoid WBRT in patients with advanced breast cancer treated with high-dose chemotherapy and autologous bone marrow transplantation (HDC/ABMT) in whom brain metastases were diagnosed. Methods. A retrospective review of our experience from 1996 to 2001 was performed to identify patients who underwent HDC/ABMT for advanced breast cancer and brain metastasis. They were able to conduct GKS as initial management to avoid or delay WBRT in 12 patients following HDC/ABMT. All patients were women. The median age was 48 years (range 30–58 years). The Karnofsky Performance Scale score was 70 (range 60–90). All lesions were treated with a median prescription dose of 17 Gy (range 15–18 Gy) prescribed to the 50% isodose. Median survival was 11.5 months. Five patients (42%) had no evidence of central nervous system disease progression and no further treatment was given. Four patients were retreated with GKS and three of them eventually received WBRT as well. Two patients were treated with WBRT as the primary salvage therapy. The median time to retreatment with WBRT was 8 months after the initial GKS. Conclusions. Gamma knife radiosurgery can be effectively used for the initial management of brain metastases to avoid or delay WBRT in patients treated previously with HDC, with acceptable survival and preserved cognitive function.

202 Gamma Knife Pituitary Sblation for Chronic Cancer Pain Control

Neurosurgery ◽  
2017 ◽  
Vol 64 (CN_suppl_1) ◽  
pp. 254-254
Author(s):  
Richard L Weiner
Keyword(s):  
Pituitary Gland ◽  
End Of Life ◽  
Gamma Knife ◽  
Anterior Pituitary ◽  
Gamma Knife Radiosurgery ◽  
High Dose ◽  
Intractable Pain ◽  
Pituitary Insufficiency ◽  
Alcohol Injection ◽  
Pituitary Ablation

Abstract INTRODUCTION Neurosurgeons are, at times, called upon to help manage cancer patients with intractable, progressive pain towards the end of life when the common treatment modalities including high dose narcotics become ineffective. Various neurosurgical interventions, either destructive or neuromodulatory in nature, can offer quality of life enhancement to palliative care. METHODS Gamma Knife radiosurgery was performed focusing on the anterior pituitary gland. RESULTS >7 patients presenting with a variety of metastatic cancer diagnoses in intractable pain were given 200gy of focused cobalt 60 energy to the anterior pituitary with significant improvements in all patients chronic, intractable pain which greatly helped their end of life experience. Patient survival time ranged from 3 months to 2 years. No patient developed pituitary insufficiency. One patient underwent autopsy histologic evaluation of the pituitary gland. No patient developed visual disturbances. CONCLUSION Pituitary ablation for metastatic bony cancer via alcohol injection has been around for years but infrequently thought of as a current treatment. Gamma Knife radiosurgery is a noninvasive method of partial pituitary ablation without signficant side effects.

scholarly journals Fractionated Gamma Knife radiosurgery for skull base meningiomas: a single-institution experience

2019 ◽  
Vol 46 (6) ◽  
pp. E8 ◽  
Author(s):  
Krishna C. Joshi ◽  
Alankrita Raghavan ◽  
Baha’eddin Muhsen ◽  
Jason Hsieh ◽  
Hamid Borghei-Razavi ◽  
...  
Keyword(s):  
Skull Base ◽  
Gamma Knife ◽  
Tumor Volume ◽  
Gamma Knife Radiosurgery ◽  
Cranial Neuropathy ◽  
High Dose ◽  
Perilesional Edema ◽  
The Mean ◽  
Skull Base Meningiomas

OBJECTIVEGamma Knife radiosurgery (GKRS) has been successfully used for the treatment of intracranial meningiomas given its steep dose gradients and high-dose conformality. However, treatment of skull base meningiomas (SBMs) may pose significant risk to adjacent radiation-sensitive structures such as the cranial nerves. Fractionated GKRS (fGKRS) may decrease this risk, but until recently it has not been practical with traditional pin-based systems. This study reports the authors’ experience in treating SBMs with fGKRS, using a relocatable, noninvasive immobilization system.METHODSThe authors performed a retrospective review of all patients who underwent fGKRS for SBMs between 2013 and 2018 delivered using the Extend relocatable frame system or the Icon system. Patient demographics, pre- and post-GKRS tumor characteristics, perilesional edema, prior treatment details, and clinical symptoms were evaluated. Volumetric analysis of pre-GKRS, post-GKRS, and subsequent follow-up visits was performed.RESULTSTwenty-five patients met inclusion criteria. Nineteen patients were treated with the Icon system, and 6 patients were treated with the Extend system. The mean pre-fGKRS tumor volume was 7.62 cm3 (range 4.57–13.07 cm3). The median margin dose was 25 Gy delivered in 4 (8%) or 5 (92%) fractions. The median follow-up time was 12.4 months (range 4.7–17.4 months). Two patients (9%) experienced new-onset cranial neuropathy at the first follow-up. The mean postoperative tumor volume reduction was 15.9% with 6 patients (27%) experiencing improvement of cranial neuropathy at the first follow-up. Median first follow-up scans were obtained at 3.4 months (range 2.8–4.3 months). Three patients (12%) developed asymptomatic, mild perilesional edema by the first follow-up, which remained stable subsequently.CONCLUSIONSfGKRS with relocatable, noninvasive immobilization systems is well tolerated in patients with SBMs and demonstrated satisfactory tumor control as well as limited radiation toxicity. Future prospective studies with long-term follow-up and comparison to single-session GKRS or fractionated stereotactic radiotherapy are necessary to validate these findings and determine the efficacy of this approach in the management of SBMs.

Lineac- and Gamma-Knife Radiosurgery for Angiographically Occult Vascular Malformations

1994 ◽  
pp. 195-208
Author(s):  
Kazumasa Ehara ◽  
Norihiko Tamaki ◽  
Katsuzo Fujita ◽  
Atsufumi Kawamura ◽  
Kazufumi Imanaka ◽  
...  
Keyword(s):  
Gamma Knife ◽  
Vascular Malformations ◽  
Gamma Knife Radiosurgery

Worldwide variance in the potential utilization of Gamma Knife radiosurgery

2016 ◽  
Vol 125 (Supplement_1) ◽  
pp. 160-165 ◽  
Author(s):  
Travis Hamilton ◽  
L. Dade Lunsford
Keyword(s):  
Gamma Knife ◽  
Malignant Tumors ◽  
Vascular Malformations ◽  
Gamma Knife Radiosurgery ◽  
Pituitary Tumors ◽  
Cavernous Malformations ◽  
Electronic Survey ◽  
Significant Variance ◽  
Health Care Barriers

OBJECTIVEThe role of Gamma Knife radiosurgery (GKRS) has expanded worldwide during the past 3 decades. The authors sought to evaluate whether experienced users vary in their estimate of its potential use.METHODSSixty-six current Gamma Knife users from 24 countries responded to an electronic survey. They estimated the potential role of GKRS for benign and malignant tumors, vascular malformations, and functional disorders. These estimates were compared with published disease epidemiological statistics and the 2014 use reports provided by the Leksell Gamma Knife Society (16,750 cases).RESULTSRespondents reported no significant variation in the estimated use in many conditions for which GKRS is performed: meningiomas, vestibular schwannomas, and arteriovenous malformations. Significant variance in the estimated use of GKRS was noted for pituitary tumors, craniopharyngiomas, and cavernous malformations. For many current indications, the authors found significant variance in GKRS users based in the Americas, Europe, and Asia. Experts estimated that GKRS was used in only 8.5% of the 196,000 eligible cases in 2014.CONCLUSIONSAlthough there was a general worldwide consensus regarding many major indications for GKRS, significant variability was noted for several more controversial roles. This expert opinion survey also suggested that GKRS is significantly underutilized for many current diagnoses, especially in the Americas. Future studies should be conducted to investigate health care barriers to GKRS for many patients.

Treatment of unresectable malignant rhabdoid tumor of the orbit with tandem high-dose chemotherapy and gamma-knife radiosurgery

2006 ◽  
Vol 47 (6) ◽  
pp. 846-850 ◽  
Author(s):  
Hiroyoshi Watanabe ◽  
Tsutomu Watanabe ◽  
Michiya Kaneko ◽  
Hiroko Suzuya ◽  
Toshihiro Onishi ◽  
...  
Keyword(s):  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
High Dose Chemotherapy ◽  
Rhabdoid Tumor ◽  
High Dose ◽  
Malignant Rhabdoid Tumor
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