Gamma Knife Radiosurgery for Brain Metastases from Breast Cancer

Objective

The authors conducted a retrospective cohort study to determine prognostic factors and treatment outcomes of brain metastases (BM) from breast cancer (BC) after Gamma Knife radiosurgery (GKS).

Methods

Pathologic and clinical features, and outcomes were analyzed in a cohort of 62 patients with BM from BC treated by GKS. The Kaplan-Meier method, the log-rank test, and Cox''s proportional hazards model were used to assess prognostic factors.

Results

Median survival after GKS was 73.0 weeks (95% confidence interval, 46.0-100.1). HER2+ [hazard ratio (HR) 0.441; p=0.045], Karnofsky performance scale (KPS) ≥70 (RR 0.416; p=0.050) and systemic chemotherapy after GKS (RR 0.282; p=0.001) were found to be a favorable prognostic factor of overall survival. Actuarial local control (LC) rate were 89.5±4.5% and 70.5±6.9% at 6 and 12 months after GKS, respectively. No prognostic factors were found to affect LC rate. Uni- and multivariate analysis revealed that the distant control (DC) rate was higher in patients with; a small number (≤3) of metastasis (HR 0.300; p=0.045), no known extracranial metastasis (p=0.013, log-rank test), or the HER2+ subtype (HR 0.267; p=0.027). Additional whole brain radiation therapy and metastasis volume were not found to be significantly associated with LC, DC, or overall survival.

Conclusion

The treatment outcomes of patients with newly diagnosed BM from BC treated with GKS could be affected primarily by intrinsic subtype, KPS, and systemic chemotherapy. Therapeutic strategy and prognosis scoring system should be individualized based on considerations of intrinsic subtype in addition to traditionally known parameters related to stereotactic radiosurgery.     

Gamma Knife Radiosurgery for Brainstem Metastasis

Objective

Brainstem metastases are rarely operable and generally unresponsive to conventional radiation therapy or chemotherapy. Recently, Gamma Knife Radiosurgery (GKRS) was used as feasible treatment option for brainstem metastasis. The present study evaluated our experience of brainstem metastasis which was treated with GKRS.

Methods

Between November 1992 and June 2010, 32 patients (23 men and 9 women, mean age 56.1 years, range 39-73) were treated with GKRS for brainstem metastases. There were metastatic lesions in pons in 23, the midbrain in 6, and the medulla oblongata in 3 patients, respectively. The primary tumor site was lung in 21, breast in 3, kidney in 2 and other locations in 6 patients. The mean tumor volume was 1,517 mm³ (range, 9-6,000), and the mean marginal dose was 15.9 Gy (range, 6-23). Magnetic Resonance Imaging (MRI) was obtained every 2-3 months following GKRS. Follow-up MRI was possible in 24 patients at a mean follow-up duration of 12.0 months (range, 1-45). Kaplan-Meier survival analysis was used to evaluate the prognostic factors.

Results

Follow-up MRI showed tumor disappearance in 6, tumor shrinkage in 14, no change in tumor size in 1, and tumor growth in 3 patients, which translated into a local tumor control rate of 87.5% (21 of 24 tumors). The mean progression free survival was 12.2 months (range, 2-45) after GKRS. Nine patients were alive at the completion of the study, and the overall mean survival time after GKRS was 7.7 months (range, 1-22). One patient with metastatic melanoma experienced intratumoral hemorrhage during the follow-up period. Survival was found to be associated with score of more than 70 on Karnofsky performance status and low recursive partitioning analysis class (class 1 or 2), in terms of favorable prognostic factors.

Conclusion

GKRS was found to be safe and effective for management of brainstem metastasis. The integral clinical status of patient seems to be important in determining the overall survival time.     

Multiple Gamma Knife Radiosurgery for Multiple Metachronous Brain Metastases Associated with Lung Cancer : Survival Time

Objective

We compared the survival time between patients with multiple gamma knife radiosurgery (GKRS) and patients with a single GKRS plus whole brain radiation therapy (WBRT), in patients with multiple metachronous brain metastases from lung cancer.

Methods

From May 2006 to July 2010, we analyzed 31 patients out of 112 patients who showed multiple metachronous brain metastases. 20 out of 31 patients underwent multiple GKRS (group A) and 11 patients underwent a single GKRS plus WBRT (group B). We compared the survival time between group A and B. Kaplan-Meier method and Cox proportional hazards were used to analyze relationship between survival and 1) the number of lesions in each patient, 2) the average volume of lesions in each patient, 3) the number of repeated GKRS, and 4) the interval of development of new lesions, respectively.

Results

Median survival time was 18 months (range 6-50 months) in group A and 6 months (range 3-18 months) in group B. Only the average volume of individual lesion (over 10 cc) was negatively related with survival time according to Kaplan-Meier method. Cox-proportional hazard ratio of each variable was 1.1559 for the number of lesions, 1.0005 for the average volume of lesions, 0.0894 for the numbers of repeated GKRS, and 0.5970 for the interval of development of new lesions.

Conclusion

This study showed extended survival time in group A compared with group B. Our result supports that multiple GKRS is of value in extending the survival time in patients with multiple metachronous brain metastases, and that the number of the lesions and the frequency of development of new lesions are not an obstacle in treating patients with GKRS.     

Clinical Outcomes of Gamma Knife Radiosurgery for Metastatic Brain Tumors from Gynecologic Cancer : Prognostic Factors in Local Treatment Failure and Survival

ObjectiveBrain metastases in gynecologic cancer (ovarian, endometrial, and cervical cancer) patients are rare, and the efficacy of Gamma Knife Radiosurgery (GKRS) to treat these had not been evaluated. We assessed the efficacy of GKRS and prognostic factors for tumor control and survival in brain metastasis from gynecologic cancers.MethodsThis retrospective study was approved by the institutional review board. From May 1995 to October 2012, 26 women (mean age 51.3 years, range 27–70 years) with metastatic brain tumors from gynecologic cancer were treated with GKRS. We reviewed their outcomes, radiological responses, and clinical status.ResultsIn total 24 patients (59 lesions) were available for follow-up imaging. The median follow-up time was 9 months. The mean treated tumor volume at the time of GKRS was 8185 mm³ (range 10–19500 mm³), and the median dose delivered to the tumor margin was 25 Gy (range, 10–30 Gy). A local tumor control rate was 89.8% (53 of 59 tumors). The median overall survival was 9.5 months after GKRS (range, 1–102 months). Age-associated multivariate analysis indicated that the Karnofsky performance status (KPS), the recursive partitioning analysis (RPA) classification, and the number of treated lesions were significant prognostic factors for overall survival (HR=0.162, p=0.008, HR=0.107, p=0.038, and HR=2.897, p=0.045, respectively).ConclusionGKRS is safe and effective for the management of brain metastasis from gynecologic cancers. The clinical status of the patient is important in determining the overall survival time.     

Radiosurgical Techniques and Clinical Outcomes of Gamma Knife Radiosurgery for Brainstem Arteriovenous Malformations

Objective

Brainstem arteriovenous malformation (AVM) is rare and radiosurgical management is complicated by the sensitivity of the adjacent neurological structures. Complete obliteration of the nidus is not always possible. We describe over 20 years of radiosurgical procedures for brainstem AVMs, focusing on clinical outcomes and radiosurgical techniques.

Methods

Between 1992 and 2011, the authors performed gamma knife radiosurgery (GKRS) in 464 cerebral AVMs. Twenty-nine of the 464 patients (6.3%) reviewed had brainstem AVMs. This series included sixteen males and thirteen females with a mean age of 30.7 years (range : 5-71 years). The symptoms that led to diagnoses were as follows : an altered mentality (5 patients, 17.3%), motor weakness (10 patients, 34.5%), cranial nerve symptoms (3 patients, 10.3%), headache (6 patients, 20.7%), dizziness (3 patients, 10.3%), and seizures (2 patients, 6.9%). Two patients had undergone a previous nidus resection, and three patients had undergone a previous embolization. Twenty-four patients underwent only GKRS. With respect to the nidus type and blood flow, the ratio of compact type to diffuse type and high flow to low flow were 17 : 12 and 16 : 13, respectively. In this series, 24 patients (82.8%) had a prior hemorrhage. The mean target volume was 1.7 cm³ (range 0.1-11.3 cm³). The mean maximal and marginal radiation doses were 38.5 Gy (range 28.6-43.6 Gy) and 23.4 Gy (range 18-27 Gy), and the mean isodose profile was 61.3% (range 50-70%).

Results

Twenty-four patients had brainstem AVMs and were followed for more than 3 years. Obliteration of the AVMs was eventually documented in 17 patients (70.8%) over a mean follow-up period of 77.5 months (range 36-216 months). With respect to nidus type and blood flow, the obliteration rate of compact types (75%) was higher than that of diffuse types (66.7%), and the obliteration rate of low flow AVMs (76.9%) was higher than that of high flow AVMs (63.6%) (p<0.05). Two patients (6.9%) with three hemorrhagic events suffered a hemorrhage during the follow-up period. The annual bleeding rate of AVM after GKRS was 1.95% per year. No adverse radiation effects or delayed cystic formations were found.

Conclusion

GKRS has an important clinical role in treatment of brainstem AVMs, which carry excessive surgical risks. Angiographic features and radiosurgical techniques using a lower maximal dose with higher isodose profiles are important for lesion obliteration and the avoidance of complications.     

伽玛刀治疗原发性三叉神经痛临床随访疗效分析

目的总结分析伽玛刀治疗原发性三叉神经痛（ITN）的效果。方法对132例ITN患者进行了伽玛刀治疗，随访77例，其中早期选择三叉神经根邻近半月节处照射治疗16例，后期选择三叉神经根人脑桥处（脑桥段）照射治疗6例；选用4mm单准直器照射56例，多准直器照射21例；照射中心剂量〈70Gy27例，70-90Gy50例。结果随访3～47个月，平均25．6个月，66例（85．7％）有效，其中完全缓解41例（53．2％），部分缓解25例（32．5％）；无效11例（14．3％）；出现相关并发症（面部麻木）13例（16．9％）。结论 伽玛刀治疗1TN有良好效果，是一种安全、成熟、副作用少的治疗技术。     

Retrospective Analysis on 76 Cases of Cerebral Arteriovenous Malformations Treated by Gamma Knife Radiosurgery

Objective

Outcome of gamma knife radiosurgery (GKS) in the consecutive 100 cases with cerebral arteriovenous malformations (AVMs) was analyzed.

Methods

Data from initial 100 patients treated with GKS in the authors'' institute were reviewed retrospectively. Spetzler-Martin grade at diagnosis were I in 18 patients, II in 27, III in 36, IV in 11, and V in 8. Thirty-five patients had experienced previous bleeding, 27 patients presented with seizure, and 31 patients presented with headache. The mean volume of the lesion was 4.3 cm³ (0.1-29.3 cm³). The median radiation dose delivered to the margin was 20.0 Gy (13-32 Gy). Mean follow-up period was 37.5 months (5-63 months).

Results

Angiographic follow-up was performed in 48 patients at least 2 years after GKS. Sixteen patients were lost in follow up following 2 years from GKS. Twenty-eight of 48 patients (58%) showed complete obliteration and 20 patients (42%) showed partial obliteration. Seven patients presented with post-GKS hemorrhage. Adverse radiation effect (ARE) was observed at follow-up MRI in 25 of 76 patients, and it was symptomatic in 5 patients. Complete obliteration was confirmed in 24 of 31 (77%) patients with volume less than 4 cm³, meanwhile only 4 of 17 (24%) patients with volume of 4 cm³ or more showed complete obliteration. Complete obliteration rate was 67% with 20 Gy or higher marginal dose, 63% with 15-20 Gy, and 17% with less than 15 Gy.

Conclusion

GKS can provide high rates of obliteration with acceptable risk of morbidity in a subgroup of small AVMs. However, overall outcome in whole spectrum of AVMs, in which large proportion of cases have unfavorable characteristics for radiosurgery, is much worse. More effective therapeutic strategy needs to be developed for large AVMs that are difficult to be managed with current available treatment modalities.     

伽玛刀在海绵窦脑膜瘤治疗中的价值

目的探讨伽玛刀在海绵窦脑膜瘤治疗中的效果。方法1997年至2004年间93例海绵窦脑膜瘤患者接受了伽玛刀治疗。其中57例有开颅手术史,36例为初发。治疗前肿瘤容积为1.3～128.6cm^3（平均24.18cm^3）,采用40%～60%（平均48%）的等剂量曲线,边缘剂量为7～18Gy（平均10.9Gy）,中心剂量为16～40Gy（平均22.5Gy）,等中心点为2～21个（平均8.7个）。结果本组93例患者获得36～78个月（平均43.7个月）的影像学随访,其中肿瘤消失12例（12.9%）,肿瘤缩小37例（39.8%）,肿瘤无明显变化26例（28.0%）,肿瘤增大18例（19.3%）,肿瘤总控制率为80.6%。结论对于累及海绵窦区的脑膜瘤,伽玛刀治疗手术风险小,并发症少,长期随访效果较好。     

Preliminary Report of Multisession Gamma Knife Radiosurgery for Benign Perioptic Lesions: Visual Outcome in 22 Patients

Objective

Radiosurgery may be contraindicated for lesions adjacent to the optic pathways because of the substantial risk of visual complication. Multisession radiosurgery has been tried as a compromise between single session radiosurgery and fractionated radiotherapy. The purpose of this study is to evaluate the outcomes of multisession gamma knife radiosurgery (GKRS) in 22 patients with perioptic lesions of benign pathology.

Methods

In all 22 cases, the lesions were within 1 mm of the optic apparatus and were therefore not considered suitable for single session radiosurgery. Radiation was delivered in 3 to 4 fractions with a median cumulated marginal dose of 20 Gy (range, 15-20 Gy).

Results

During a mean follow-up of 29 months (range, 14-44 months), tumor control was achieved in 21 patients. Visual function improved in 7 patients, remained unchanged in 14 patients, and deteriorated in 1 patient with tumor progression. No other complication was observed.

Conclusion

This preliminary result supports the idea that multisession GKRS may be an effective and safe alternative for treatment in perioptic lesions that are unsuitable for single session radiosurgery.     

Efficacy and Safety of Fractionated Stereotactic Radiosurgery for Large Brain Metastases

Objective

To investigate the efficacy and safety of fractionated stereotactic radiosurgery for large brain metastases (BMs).

Methods

Between June 2011 and December 2013, a total of 38 large BMs >3.0 cm in 37 patients were treated with fractionated Cyberknife radiosurgery. These patients comprised 16 men (43.2%) and 21 women, with a median age of 60 years (range, 38-75 years). BMs originated from the lung (n=19, 51.4%), the gastrointestinal tract (n=10, 27.0%), the breast (n=5, 13.5%), and other tissues (n=3, 8.1%). The median tumor volume was 17.6 cc (range, 9.4-49.6 cc). For Cyberknife treatment, a median peripheral dose of 35 Gy (range, 30-41 Gy) was delivered in 3 to 5 fractions.

Results

With a median follow-up of 10 months (range, 1-37 months), the crude local tumor control (LTC) rate was 86.8% and the estimated LTC rates at 12 and 24 months were 87.0% and 65.2%, respectively. The median overall survival (OS) and progression-free survival (PFS) rates were 16 and 11 months, respectively. The estimated OS and PFS rates at 6, 12, and 18 months were 81.1% and 65.5%, 56.8% and 44.9%, and 40.7% and 25.7%, respectively. Patient performance status and preoperative focal neurologic deficits improved in 20 of 35 (57.1%) and 12 of 17 patients (70.6%), respectively. Radiation necrosis with a toxicity grade of 2 or 3 occurred in 6 lesions (15.8%).

Conclusion

These results suggest a promising role of fractionated stereotactic radiosurgery in treating large BMs in terms of both efficacy and safety.     

Clinical Outcome in Gamma Knife Radiosurgery for Metastatic Brain Tumors from the Primary Breast Cancer : Prognostic Factors in Local Treatment Failure and Survival

Objective

Brain metastases in primary breast cancer patients are considerable sources of morbidity and mortality. Gamma knife radiosurgery (GKRS) has gained popularity as an up-front therapy in treating such metastases over traditional radiation therapy due to better neurocognitive function preservation. The aim of this study was to clarify the prognostic factors for local tumor control and survival in radiosurgery for brain metastases from primary breast cancer.

Methods

From March 2001 to May 2011, 124 women with metastatic brain lesions originating from a primary breast cancer underwent GKRS at a tertiary medical center in Seoul, Korea. All patients had radiosurgery as a primary treatment or salvage therapy. We retrospectively reviewed their clinical outcomes and radiological responses. The end point of this study was the date of patient''s death or the last follow-up examination.

Results

In total, 106 patients (268 lesions) were available for follow-up imaging. The median follow-up time was 7.5 months. The mean treated tumor volume at the time of GKRS was 6273 mm³ (range, 4.5-27745 mm³) and the median dose delivered to the tumor margin was 22 Gy (range, 20-25 Gy). Local recurrence was assessed in 86 patients (216 lesions) and found to have occurred in 36 patients (83 lesions, 38.6%) with a median time of 6 months (range, 4-16 months). A treated tumor volume >5000 mm³ was significantly correlated with poor local tumor control through a multivariate analysis (hazard risk=7.091, p=0.01). Overall survival was 79.9%, 48.3%, and 15.3% at 6, 12, and 24 months, respectively. The median overall survival was 11 months after GKRS (range, 6 days-113 months). Multivariate analysis showed that the pre-GKRS Karnofsky performance status, leptomeningeal seeding prior to initial GKRS, and multiple metastatic lesions were significant prognostic factors for reduced overall survival (hazard risk=1.94, p=0.001, hazard risk=7.13, p<0.001, and hazard risk=1.46, p=0.046, respectively).

Conclusion

GKRS has shown to be an effective and safe treatment modality for treating brain metastases of primary breast cancer. Most metastatic brain lesions initially respond to GKRS, though, many patients have further CNS progression in subsequent periods. Patients with poor Karnofsky performance status and multiple metastatic lesions are at risk of CNS progression and poor survival, and a more frequent and strict surveillance protocol is suggested in such high-risk groups.     

巨大脑胶质瘤的分次伽玛刀治疗

目的 探讨巨大脑胶质瘤的分次γ刀治疗及其疗效。方法 巨大脑胶质瘤的γ刀治疗分两次或三次完成,每次间隔1d,分次照射的周边剂量为5～10 Gy。治疗效果通过MRI和临床表现综合评估。结果 随访3～33月,28例巨大脑胶质瘤分次γ刀治疗有效率为78.6％,2例病人γ刀术后出现迟发性脑水肿。治疗效果与肿瘤分化程度有关,而与肿瘤大小无关。结论 巨大脑胶质瘤分次γ刀治疗效果显著,但其远期疗效有待进一步的临床和实验观察。     

The Variable Ellipsoid Modeling Technique as a Verification Method for the Treatment Planning System of Gamma Knife Radiosurgery

Objective

The secondary verification of Leksell Gamma Knife treatment planning system (LGP) (which is the primary verification system) is extremely important in order to minimize the risk of treatment errors. Although prior methods have been developed to verify maximum dose and treatment time, none have studied maximum dose coordinates and treatment volume.

Methods

We simulated the skull shape as an ellipsoid with its center at the junction between the mammillary bodies and the brain stem. The radiation depths of the beamlets emitted from 201 collimators were calculated based on the relationship between this ellipsoid and a single beamlet expressed as a straight line. A computer program was coded to execute the algorithm. A database system was adopted to log the doses for 31×31×31 or 29,791 matrix points allowing for future queries to be made of the matrix of interest.

Results

When we compared the parameters in seven patients, all parameters showed good correlation. The number of matrix points with a dose higher than 30% of the maximal dose was within ± 2% of LGP. The 50% dose volume, which is generally the target volume, differs maximally by 4.2%. The difference of the maximal dose ranges from 0.7% to 7%.

Conclusion

Based on the results, the variable ellipsoid modeling technique or variable ellipsoid modeling technique (VEMT) can be a useful and independent tool to verify the important parameters of LGP and make up for LGP.     

Clinical Analysis of Novalis Stereotactic Radiosurgery for Brain Metastases

Objective

The authors analyzed the effectiveness and therapeutic response of Novalis shaped beam radiosurgery for metastatic brain tumors, and the prognostic factors which influenced the outcome.

Methods

We performed a retrospective analysis of 106 patients who underwent 159 treatments for 640 metastatic brain lesions between January 2000 and April 2008. The pathologies of the primary tumor were mainly lung (45.3%), breast (18.2%) and GI tract (13.2%). We classified the patients using Radiation Therapy Oncology Group Recursive Partitioning Analysis (RPA) and then analyzed the survival and prognostic factors according to the Kaplan Meier method and univariate analysis.

Results

The overall median actuarial survival rate was 7.3 months from the time of first radiosurgery treatment while 1 and 2 year actuarial survival estimates were 31% and 14.4%, respectively. Median actuarial survival rates for RPA classes I, II, and III were 31.3 months, 7.5 months and 1.7 months, respectively. Patients'' life spans, higher Karnofsky performance scores and age correlated closely with RPA classes. However, sex and the number of lesions were not found to be significantly associated with length of survival.

Conclusion

This result suggests that Novalis radiosurgery can be a good treatment option for treatment of the patients with brain metastases.     

Growing Organized Hematomas Following Gamma Knife Radiosurgery for Cerebral Arteriovenous Malformation : Five Cases of Surgical Excision

Organized hematoma is a rare complication that can develop following gamma knife radiosurgery (GKS) for cerebral arteriovenous malformation (AVM). Here, we describe 5 patients with growing organized hematomas that developed from completely obliterated AVMs several years after GKS. The patients were 15, 16, 30, 36, and 38 years old at the time of GKS, respectively, and 3 patients were female. Four AVMs were located in the lobe of the brain, and the remaining AVM were in the thalamus. Between 2-12 years after GKS, patients developed progressive symptoms such intractable headache or hemiparesis and enhancing mass lesions were identified. Follow-up visits revealed the slow expansion of the hematomas and surrounding edema. Steroids were ineffective, and thus surgery was performed. Histology revealed organized hematomas with a capsule, but there was no evidence of residual AVMs or vascular malformation. After surgery, the neurological symptoms of all patients improved and the surrounding edema resolved. However, the hematoma continued to expand and intraventricular hemorrhage developed in 1 patient whose hematoma was only partially removed. GKS for cerebral AVM can be complicated by growing, organized hematomas that develop after complete obliteration. Growing hematomas should be surgically evacuated if they are symptomatic. Radical resection of the hematoma capsule is also strongly recommended.     

伽玛刀放射治疗听神经瘤的长期疗效分析

目的总结评价伽玛刀放射治疗对听神经瘤生长的控制作用和对肿瘤周围的颅神经功能变化的影响。方法从1997年至2005年我科伽玛刀中心采用多中心点照射治疗159例（164个）听神经瘤,其中137例有完整的随访资料。MRI随访6～96个月,平均37.2个月;临床随访6～116个月,平均36.4个月。单纯行伽玛刀治疗86例,开颅手术后再行伽玛刀治疗51例。结果肿瘤控制率为94.16%;肿瘤体积增大8例（5.84%）。术前有听力的106例患者中听力保留率为72.64%,听力下降率为27.36%。面神经功能保留率为95.50%,三叉神经功能保留率为94.16%。结论伽玛刀治疗听神经瘤有良好的控制效果,并发症少,对肿瘤周围颅神经有较高的功能保留作用。     

The Treatment Outcome of Elderly Patients with Idiopathic Trigeminal Neuralgia : Micro-Vascular Decompression versus Gamma Knife Radiosurgery

Objective

This study was designed to compare the efficacy of micro-vascular decompression (MVD) and Gamma knife radiosurgery (GKRS) for elderly idiopathic trigeminal neuralgia patients by analyzing the clinical outcome.

Methods

In the past 10 years, 27 elderly patients were treated with MVD while 18 patients were treated with GKRS (>65-years-old). We reviewed their clinical characteristics and clinical courses after treatment as well as the treatment outcomes. For patients who were treated with MVD, additional treatment methods such as rhizotomy were combined in some areas. In GKRS, we radiated the root entry zone (REZ) with the mean maximum dose of 77.8 (70-84.3) Gy and one 4 mm collimator.

Results

The mean age was 68.1 years for MVD, and 71.1 years for GKS group. The average time interval between first presenting symptom and surgery was 84.1 (1-361) months, and 51.4 (1-120) months, respectively. The mean follow-up period after the surgery was 35.9 months for MVD, and 33.1 months for GKRS. According to Pain Intensity Scale, MVD group showed better prognosis with 17 (63%) cases in grade I-II versus 10 (55.6%) cases in GKRS group after the treatment. The pain recurrence rate during follow up did not show much difference with 3 (11.1%) in MVD, and 2 (11.1%) in GKRS. After the treatment, 2 cases of facial numbness, and 1 case each of herpes zoster, cerebrospinal fluid (CSF) leakage, hearing disturbance, and subdural hematoma occurred in MVD Group. In GKRS, there was 1 (5.6%) case of dysesthesia but was not permanent. Three cases were retreated by GKRS but the prognosis was not as good as when the surgery was used as primary treatment, with 1 case of grade I-II, and 1 case of recurrence. The maximal relieve of pain was seen just after surgery in MVD group, and 1 year after treatment in GKRS group.

Conclusion

For trigeminal neuralgia patients with advanced age, MVD showed advantages in immediately relieving the pain. However, in overall, GKRS was preferable, despite the delayed pain relief, due to the lower rate of surgical complications that arise owing to the old age.