scholarly journals Advanced Gamma Knife Treatment Planning of Epilepsy

10.5772/29760 ◽  
2011 ◽  
Author(s):  
Andrew Hwang ◽  
Lijun M
Keyword(s):  
Treatment Planning ◽  
Gamma Knife

A simple treatment planning strategy for patients with multiple metastases treated with Gamma Knife surgery

2006 ◽  
Vol 105 (Supplement) ◽  
pp. 2-4 ◽  
Author(s):  
James G. Douglas ◽  
Robert Goodkin
Keyword(s):  
Mr Imaging ◽  
Treatment Planning ◽  
Gamma Knife ◽  
Gamma Knife Surgery ◽  
Planning Method ◽  
Cns Metastases ◽  
Cell Lung Carcinoma ◽  
Dose Volume Histograms ◽  
Number Of Patients ◽  
The Brain

ObjectIn a substantial number of patients treated at the authors' facility for brain metastases, additional lesions are identified at the time of Gamma Knife surgery (GKS). These lesions are often widely dispersed and may number over 10, which is the maximal number of matrices that can be currently placed for treatment with Leksell Gamma-Plan 4C. The authors describe a simple planning method for GKS in patients with multiple, widely dispersed central nervous system (CNS) metastases.MethodsTwo patients presented with three to five identified recurrent metastases from non–small cell lung carcinoma and breast carcinoma after having received whole-brain radiotherapy. At the time of treatment with GKS in each patient, spoiled-gradient Gd-enhanced magnetic resonance (MR) imaging revealed substantially more metastases than originally thought, which were widely scattered throughout all regions of the brain. The authors simplified the treatment planning approach by dividing the entire CNS contents into six contiguous, nonoverlapping matrices, which allowed for the planning, calculation, and treatment of all lesions.Two patients were successfully treated with GKS for more than 10 CNS metastases by using this simple planning method. Differing peripheral doses to varied-size lesions were delivered by prescribing to different isodose curves within any given matrix when required. Dose–volume histograms showed brain doses as follows: 10% of the total brain volume received 5 to 6.4 Gy; 25% received 3.8 to 4.8 Gy; 50% received 2.7 to 3.1 Gy; and 75% received 2.2 to 2.5 Gy.Conclusions The delineation of more metastases than appreciated on the diagnostic MR imaging is a common occurrence at the time of GKS at the authors' institution. The treatment of multiple (>10), widely dispersed CNS metastases can be simplified by the placement of multiple, contiguous, non-overlapping matrices, which can be employed to treat lesions in all areas of the brain when separate matrices cannot be utilized.

scholarly journals 111. Treatment planning in radiosurgery with GAMMA KNIFE : Accuracy & device useing CAG

1993 ◽  
Vol 49 (2) ◽  
pp. 231
Author(s):  
Eisaku Katoh ◽  
Rituo Satoh ◽  
Yoshihito Hagiwara ◽  
Norio senzui ◽  
Masami Gotoh ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Gamma Knife

Optic radiation tractography integrated into simulated treatment planning for Gamma Knife surgery

2007 ◽  
Vol 107 (4) ◽  
pp. 721-726 ◽  
Author(s):  
Keisuke Maruyama ◽  
Kyousuke Kamada ◽  
Masahiro Shin ◽  
Daisuke Itoh ◽  
Yoshitaka Masutani ◽  
...  
Keyword(s):  
Visual Field ◽  
Treatment Planning ◽  
Gamma Knife ◽  
Diffusion Tensor ◽  
Maximum Dose ◽  
Gamma Knife Surgery ◽  
Optic Radiation ◽  
Imaging Studies ◽  
Visual Field Deficits ◽  
Neurological Change

Object No definitive method of preventing visual field deficits after stereotactic radiosurgery for lesions near the optic radiation (OR) has been available so far. The authors report the results of integrating OR tractography based on diffusion tensor (DT) magnetic resonance imaging into simulated treatment planning for Gamma Knife surgery (GKS). Methods Data from imaging studies performed in 10 patients who underwent GKS for treatment of arteriovenous malformations (AVMs) located adjacent to the OR were used for the simulated treatment planning. Diffusion tensor images performed without the patient's head being secured by a stereotactic frame were used for DT tractography, and the OR was visualized by means of software developed by the authors. Data from stereotactic 3D imaging studies performed after frame fixation were coregistered with the data from DT tractography. The combined images were transferred to a GKS treatment-planning workstation. Delivered doses and distances between the treated lesions and the OR were analyzed and correlated with posttreatment neurological changes. Results In patients presenting with migraine with visual aura or occipital lobe epilepsy, the OR was located within 11 mm from AVMs. In a patient who developed new quadrantanopia after GKS, the OR had received 32 Gy. A maximum dose to the OR of less than 12 Gy did not cause new visual field deficits. A maximum dose to the OR of 8 Gy or more was significantly related to neurological change (p < 0.05), including visual field deficits and development or improvement of migraine. Conclusions Integration of OR tractography into GKS represents a promising tool for preventing GKS-induced visual disturbances and headaches. Single-session irradiation at a dose of 8 Gy or more was associated with neurological change.

SU-E-T-542: Impact of Convolution Algorithm Based Treatment Planning in Gamma Knife Radiosurgery

2013 ◽  
Vol 40 (6Part19) ◽  
pp. 330-330
Author(s):  
gopishankar natanasabapathi ◽  
Raj Kishor Bisht
Keyword(s):  
Treatment Planning ◽  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
Convolution Algorithm

Optimizing computerized treatment planning for the gamma knife by source culling

1999 ◽  
Vol 45 (5) ◽  
pp. 1339-1346 ◽  
Author(s):  
Limin Luo ◽  
Huazhong Shu ◽  
Wenxue Yu ◽  
Yulong Yan ◽  
Xudong Bao ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Gamma Knife ◽  
Computerized Treatment

Multidimensional treatment planning for gamma knife stereotactic radiosurgery

1991 ◽  
Vol 21 ◽  
pp. 232
Author(s):  
A.M. Kalend ◽  
Andrew Wu ◽  
A.H. Maitz ◽  
J.C. Flickinger ◽  
L.D. Lunsford ◽  
...  
Keyword(s):  
Stereotactic Radiosurgery ◽  
Treatment Planning ◽  
Gamma Knife ◽  
Gamma Knife Stereotactic Radiosurgery

scholarly journals Integration of rotational angiography enables better dose planning in Gamma Knife radiosurgery for brain arteriovenous malformations

2018 ◽  
Vol 129 (Suppl1) ◽  
pp. 17-25 ◽  
Author(s):  
Hirotaka Hasegawa ◽  
Shunya Hanakita ◽  
Masahiro Shin ◽  
Mariko Kawashima ◽  
Taichi Kin ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Volume Ratio ◽  
Rotational Angiography ◽  
Rank Tests ◽  
Signed Rank ◽  
Dose Planning ◽  
Before And After

OBJECTIVEIn Gamma Knife radiosurgery (GKS) for arteriovenous malformations (AVMs), CT angiography (CTA), MRI, and digital subtraction angiography (DSA) are generally used to define the nidus. Although the AVM angioarchitecture can be visualized with superior resolution using rotational angiography (RA), the efficacy of integrating RA into the GKS treatment planning process has not been elucidated.METHODSUsing data collected from 25 consecutive patients with AVMs who were treated with GKS at the authors’ institution, two neurosurgeons independently created treatment plans for each patient before and after RA integration. For all patients, MR angiography, contrasted T1 imaging, CTA, DSA, and RA were performed before treatment. The prescription isodose volume before (PIVB) and after (PIVA) RA integration was measured. For reference purposes, a reference target volume (RTV) for each nidus was determined by two other physicians independent of the planning surgeons, and the RTV covered by the PIV (RTVPIV) was established. The undertreated volume ratio (UVR), overtreated volume ratio (OVR), and Paddick’s conformal index (CI), which were calculated as RTVPIV/RTV, RTVPIV/PIV, and (RTVPIV)2/(RTV × PIV), respectively, were measured by each neurosurgeon before and after RA integration, and the surgeons’ values at each point were averaged. Wilcoxon signed-rank tests were used to compare the values obtained before and after RA integration. The percentage change from before to after RA integration was calculated for the average UVR (%ΔUVRave), OVR (%ΔOVRave), and CI (%ΔCIave) in each patient, as ([value after RA integration]/[value before RA integration] − 1) × 100. The relationships between prior histories and these percentage change values were examined using Wilcoxon signed-rank tests.RESULTSThe average values obtained by the two surgeons for the median UVR, OVR, and CI were 0.854, 0.445, and 0.367 before RA integration and 0.882, 0.478, and 0.463 after RA integration, respectively. All variables significantly improved after compared with before RA integration (UVR, p = 0.009; OVR, p < 0.001; CI, p < 0.001). Prior hemorrhage was significantly associated with larger %ΔOVRave (median 20.8% vs 7.2%; p = 0.023) and %ΔCIave (median 33.9% vs 13.8%; p = 0.014), but not %ΔUVRave (median 4.7% vs 4.0%; p = 0.449).CONCLUSIONSIntegrating RA into GKS treatment planning may permit better dose planning owing to clearer visualization of the nidus and, as such, may reduce undertreatment and waste irradiation. Further studies examining whether the observed RA-related improvement in dose planning also improves the radiosurgical outcome are needed.

SU-FF-T-311: Monte-Carlo Calculation of Integral Dose for Gamma Knife Treatment Planning

2007 ◽  
Vol 34 (6Part12) ◽  
pp. 2473-2473
Author(s):  
K Li ◽  
J Wang ◽  
M Cai ◽  
N Mayr
Keyword(s):  
Monte Carlo ◽  
Treatment Planning ◽  
Gamma Knife ◽  
Monte Carlo Calculation ◽  
Integral Dose
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