Gamma Knife surgery for recurrent or persistent Cushing disease: long-term results and evaluation of biological effective dose in a series of 26 patients

Object Trigeminal schwannomas are rare intracranial tumors. In the past, resection and radiation therapy were the mainstays of their treatment. More recently, neurosurgeons have begun to use radiosurgery in the treatment of trigeminal schwannomas because of its successful use in the treatment of vestibular schwannomas. In this article the authors evaluate the radiological and clinical outcomes in a series of patients in whom Gamma Knife surgery (GKS) was used to treat trigeminal schwannomas. Methods Twenty-six patients with trigeminal schwannomas underwent GKS at the University of Virginia Lars Lek-sell Gamma Knife Center between 1989 and 2005. Five of these patients had neurofibromatosis and one patient was lost to follow up. The median tumor volume was 3.96 cm3, and the mean follow-up period was 48.5 months. The median prescription radiation dose was 15 Gy, and the median prescription isodose configuration was 50%. There was clinical improvement in 18 patients (72%), a stable lesion in four patients (16%), and worsening of the disease in three patients (12%). On imaging, the schwannomas shrank in 12 patients (48%), remained stable in 10 patients (40%), and increased in size in three patients (12%). These results were comparable for primary and adjuvant GKSs. No tumor growth following GKS was observed in the patients with neurofibromatosis. Conclusions Gamma Knife surgery affords a favorable risk-to-benefit profile for patients harboring trigeminal schwannomas. Larger studies with open-ended follow-up review will be necessary to determine the long-term results and complications of GKS in the treatment of trigeminal schwannomas.

Download Full-text

Long-term results of gamma knife surgery for growth hormone—producing pituitary adenoma: is the disease difficult to cure?

Journal of Neurosurgery ◽

10.3171/sup.2005.102.s_supplement.0119 ◽

2005 ◽

Vol 102 (Special_Supplement) ◽

pp. 119-123 ◽

Cited By ~ 5

Author(s):

Tatsuya Kobayashi ◽

Yoshimasa Mori ◽

Yukio Uchiyama ◽

Yoshihisa Kida ◽

Shigeru Fujitani

Keyword(s):

Growth Hormone ◽

Gamma Knife ◽

Pituitary Adenomas ◽

Gamma Knife Surgery ◽

Long Term Results ◽

Content Type ◽

The Mean ◽

Dose Radiation ◽

Fine Print

Object. The authors conducted a study to determine the long-term results of gamma knife surgery for residual or recurrent growth hormine (GH)—producing pituitary adenomas and to compare the results with those after treatment of other pituitary adenomas. Methods. The series consisted of 67 patients. The mean tumor diameter was 19.2 mm and volume was 5.4 cm3. The mean maximum dose was 35.3 Gy and the mean margin dose was 18.9 Gy. The mean follow-up duration was 63.3 months (range 13–142 months). The tumor resolution rate was 2%, the response rate 68.3%, and the control rate 100%. Growth hormone normalization (GH < 1.0 ng/ml) was found in 4.8%, nearly normal (< 2.0 ng/ml) in 11.9%, significantly decreased (< 5.0 ng/ml) in 23.8%, decreased in 21.4%, unchanged in 21.4%, and increased in 16.7%. Serum insulin-like growth factor (IGF)—1 was significantly decreased (IGF-1 < 400 ng/ml) in 40.7%, decreased in 29.6%, unchanged in 18.5%, and increased in 11.1%, which was almost parallel to the GH changes. Conclusions. Gamma knife surgery was effective and safe for the control of tumors; however, normalization of GH and IGF-1 secretion was difficult to achieve in cases with large tumors and low-dose radiation. Gamma knife radiosurgery is thus indicated for small tumors after surgery or medication therapy when a relatively high-dose radiation is required.

Download Full-text

Long-term results of gamma knife surgery for growth hormone—producing pituitary adenoma: is the disease difficult to cure?

Journal of Neurosurgery ◽

10.3171/jns.2005.102.s_supplement.0119 ◽

2005 ◽

Vol 102 (s_supplement) ◽

pp. 119-123 ◽

Cited By ~ 37

Author(s):

Tatsuya Kobayashi ◽

Yoshimasa Mori ◽

Yukio Uchiyama ◽

Yoshihisa Kida ◽

Shigeru Fujitani

Keyword(s):

Growth Hormone ◽

Pituitary Adenoma ◽

Gamma Knife ◽

Gamma Knife Surgery ◽

Long Term Results

Download Full-text

Long-Term Results for Trigeminal Schwannomas Treated With Gamma Knife Surgery

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2013.09.010 ◽

2013 ◽

Vol 87 (5) ◽

pp. 1115-1121 ◽

Cited By ~ 13

Author(s):

Toshinori Hasegawa ◽

Takenori Kato ◽

Hiroshi Iizuka ◽

Yoshihisa Kida

Keyword(s):

Gamma Knife ◽

Gamma Knife Surgery ◽

Long Term Results

Download Full-text

Long-term results of Gamma Knife surgery for arteriovenous malformations: 10- to 15-year follow up in patients treated with lower doses

Journal of Neurosurgery ◽

10.3171/sup.2006.105.7.64 ◽

2006 ◽

Vol 105 (Supplement) ◽

pp. 64-68 ◽

Cited By ~ 19

Author(s):

Hiroshi K. Inoue

Keyword(s):

Adverse Effects ◽

Brain Edema ◽

Gamma Knife ◽

Arteriovenous Malformations ◽

Cyst Formation ◽

Gamma Knife Surgery ◽

Surrounding Tissue ◽

Long Term Results

ObjectSeveral adverse effects such as brain edema, necrosis, arterial stenosis, hemorrhage after obliteration, and delayed cyst formation have been reported as early and late complications of Gamma Knife surgery (GKS) for arteriovenous malformations (AVMs). These adverse effects seem to be decreased in a lower-dose treatment regimen compared with the classic higher margin doses of 25 Gy because the radiation insult to the surrounding tissue is minimized. Long-term results of lower-dose GKS for AVMs are presented.MethodsOne hundred fourteen patients with AVMs were treated with lower-dose GKS (≤ 20-Gy margin dose). There were 68 male and 46 female patients, aged 10 to 68 years (mean 35.4 years). The evaluation of AVM nidi and dose planning were performed using both angiography and MR imaging in all cases to exclude the surrounding brain tissue. The mean margin dose was 19.5 Gy.Total angiographically documented obliteration was achieved in 65 (85.5%) of 76 patients. Eleven patients underwent a second treatment, including staged treatment for large AVMs; total AVM obliteration has been achieved in six of them to date. Of 38 patients in whom no follow-up examination could be performed, 19 of them were healthy and 10 were lost from follow up. Nine patients experienced bleeding during the latency period, and four of them suffered lethal hemorrhage. Symptomatic early complications were extensive brain edema after repeated GKS in one patient and an adverse effect on the internal capsule in one. Delayed cyst formation was found in one patient as a late complication 10 years after treatment. No treatment-related death has been noted to date.Conclusions Lower-dose GKS is an effective and safe treatment for patients with AVMs and may decrease long-term adverse effects to the surrounding brain.

Download Full-text

Long-term Results of Gamma Knife Surgery for Partially Embolized Arteriovenous Malformations

Neurosurgery ◽

10.1227/neu.0b013e3182720280 ◽

2012 ◽

Vol 71 (6) ◽

pp. 1139-1148 ◽

Cited By ~ 41

Author(s):

Lucia Schwyzer ◽

Chun-Po Yen ◽

Avery Evans ◽

Sebastian Zavoian ◽

Ladislau Steiner

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Combined Treatment ◽

Gamma Knife Surgery ◽

Long Term Results ◽

Historical Series ◽

Radiation Induced ◽

The Mean ◽

Induced Changes

ABSTRACT BACKGROUND: The effectiveness and risk of Gamma Knife surgery (GKS) in the management of partially embolized cerebral arteriovenous malformations (AVMs) remain to be elucidated. OBJECTIVE: To evaluate the long-term imaging and clinical outcomes of GKS in AVM patients who had undergone previous partial embolization and compare the results with patients treated with GKS alone. METHODS: A total of 215 embolized AVMs were analyzed. The mean patient age was 32.9 years. The mean volume of the nidus was 4.6 mL (range, 0.1-29.4 mL), and the mean prescription dose was 19.6 Gy (range, 4-28 Gy). This group was compared with 729 nonembolized AVMs. RESULTS: After embolization and GKS, angiographically confirmed total obliteration of the AVMs was significantly lower (33%) compared with patients in whom GKS was used alone (60.9%; P < .001). However, the mean nidus size was larger and the Spetzler-Martin grade was higher for the embolized AVMs compared with the nonembolized AVMs. Radiation-induced changes occurred more often in the embolized (43.4%) than the nonembolized (33.4%) AVMs (P = .028). Permanent neurological deficits associated with radiation-induced changes occurred in 2.7% of the embolized compared with 1.3% of the nonembolized patients (P = .14). CONCLUSION: In our retrospective and historical series, the long-term results suggest that the obliteration rate is significantly lower in embolized AVMs compared with nonembolized AVMs, also because of the fact that the combined treatment is applied to higher grade AVMs; the percentage of grade III-V AVMs was 58.6% and 48.8% for nonembolized AVMs.

Download Full-text

Long-term results of Gamma Knife surgery for optic nerve sheath meningioma

Journal of Neurosurgery ◽

10.3171/2010.7.gks10869 ◽

2010 ◽

Vol 113 (Special_Supplement) ◽

pp. 28-33 ◽

Cited By ~ 11

Author(s):

Dong Liu ◽

Desheng Xu ◽

Zhiyuan Zhang ◽

Yipei Zhang ◽

Yanhe Li ◽

...

Keyword(s):

Optic Nerve ◽

Gamma Knife ◽

Gamma Knife Surgery ◽

Optic Nerve Sheath ◽

Long Term Results ◽

Nerve Sheath ◽

Optic Nerve Sheath Meningioma ◽

The Mean

Object The goal of this study was to assess the long-term results of Gamma Knife surgery (GKS) in patients harboring an optic nerve sheath meningioma (ONSM). Methods Thirty patients harboring an ONSM were treated with GKS between 1998 and 2003. Gamma Knife surgery was performed as the sole treatment option in 21 of these patients and resection had been performed previously in 9 patients. The mean volume of the tumor at the time of GKS was 3.6 cm3 (range 1.4–9.7 cm3), and the mean prescription peripheral dose was 13.3 Gy (range 10–17 Gy). The mean number of isocenters used to treat these lesions was 8 (range 5–14 isocenters). Results At a median follow-up of 56 months, visual acuity improved in 11 patients, remained stable in 13 patients (including 4 patients who were completely blind before GKS), and deteriorated in 6 patients. Follow-up images were available in all patients and showed tumor regression in 20 patients and stable tumor in 8 patients. Persistent imaging evidence of progression was only present in 2 patients. With the exception of reversible conjunctival edema in 4 cases, no other serious acute side effect was observed. Conclusions Gamma Knife surgery provides long-term tumor control for ONSM. The results of this study add substantial evidence that GKS may definitely become a standard treatment approach in selected cases of ONSM.

Download Full-text

Long-term results of Leksell gamma knife surgery for trigeminal schwannomas

Journal of Neurosurgery ◽

10.3171/jns.2005.102.s_supplement.0220 ◽

2005 ◽

Vol 102 ◽

pp. 220-224 ◽

Cited By ~ 31

Author(s):

Li Pan ◽

En-Min Wang ◽

Nan Zhang ◽

Liang-Fu Zhou ◽

Bing-Jiang Wang ◽

...

Keyword(s):

Tumor Progression ◽

Gamma Knife ◽

Growth Control ◽

Gamma Knife Surgery ◽

Neurological Deficits ◽

Long Term Results ◽

Content Type ◽

The Mean ◽

Fine Print

Object. The authors evaluated the long-term efficacy of gamma knife surgery (GKS) in patients with trigeminal schwannomas. Methods. Fifty-six patients, 31 women and 25 men (mean age 42 years), underwent GKS for trigeminal schwannomas. Fourteen had previously undergone surgery, and GKS was the primary treatment in the remaining 42 patients. The mean target volume was 8.7 cm3 (range 0.8–33 cm3); the mean maximum dose was 27 Gy (range 20–40 Gy); the mean tumor margin dose was 13.3 Gy (range 10–15 Gy); and the mean follow-up period was 68 months (range 27–114 months). Disappearance of the tumor occurred in seven patients. An obvious decrease in tumor volume was observed in 41 patients, four tumors remained unchanged, and four tumors progressed at 5, 26, 30, and 60 months, respectively. One patient with disease progression died of tumor progression at 36 months after GKS. The tumor growth control rate in this group was 93% (52 of 56 cases). Mild numbness or diplopia was relieved completely in 14 patients. Improvement of other neurological deficits was demonstrated in 25 patients. Trigeminal nerve dysfunction was either unchanged or slightly worse in 13 patients after GKS. Four patients experienced mild symptom deterioration related to tumor progression. Conclusions. Radiosurgery proved to be an effective treatment for small- and medium-sized trigeminal schwannomas. Some larger tumors are also suitable for radiosurgery if there is no significant brainstem compression.

Download Full-text

Repeat Gamma Knife surgery for trigeminal neuralgia: long-term results

Journal of Neurosurgery ◽

10.3171/2010.8.gks101075 ◽

2010 ◽

Vol 113 (Special_Supplement) ◽

pp. 178-183 ◽

Cited By ~ 17

Author(s):

Brent Y. Kimball ◽

Jeffrey M. Sorenson ◽

David Cunningham

Keyword(s):

Pain Relief ◽

Trigeminal Neuralgia ◽

Gamma Knife ◽

Trigeminal Nerve ◽

Treatment Plan ◽

Gamma Knife Surgery ◽

Long Term Results ◽

Long Term Outcome ◽

Facial Numbness

Object The purpose of this study was to assess the long-term outcome achieved after repeat Gamma Knife surgery (GKS) for trigeminal neuralgia (TN) using a uniform treatment plan. Methods Between 1985 and 2010, 53 patients underwent repeat GKS for refractory TN. In the initial GKS, which involved targeting the root entry zone of the trigeminal nerve, a maximal dose of 80 Gy was used with a 4-mm collimator so that the 50% isodose line abutted the pons. In the second GKS, the treatment plan consisted of a 70-Gy dose directed at a target 4–5 mm distal to the first target on the trigeminal nerve. The mean follow-up duration in these patients was 42 months. Outcomes were defined using the Marseille scale: excellent (Class I or II, no pain with or without medications), good (Class III or IV, ≥ 50% relief), and poor (Class V, < 50% relief). Results Trigeminal neuralgia pain was controlled (≥ 50% improvement with or without medications) after repeat GKS in 70% of patients at 1 year, 50% at 3 years, 50% at 5 years, and 50% at 10 years, as defined by a Kaplan-Meier analysis. A correlation was found between facial numbness and pain relief (p = 0.047). No difference was found between patients with Type 1 TN and those with Type 2 TN, and there was no correlation between the best relief obtained and long-term durability of relief from pain. Twenty-two patients (47.8%) described their trigeminal dysfunction in the following manner: numbness (45.6%), dry eye (10.9%), taste change (8.7%), or jaw weakness (2.2%). In only 8.7% of cases did the patient experience facial numbness that was regarded as bothersome. Conclusions Repeat GKS for TN at the doses used provides substantial long-term relief. Treatment failure occurred up to 28 months after the second GKS. Facial numbness correlated with more durable pain relief after repeat GKS in this series.

Download Full-text