Twenty-three years follow-up after low-dose Gamma Knife surgery of a brainstem juvenile pilocytic astrocytoma: a case report and review of the literature

ObjectThe treatment of solitary vestibular schwannomas by performing Gamma Knife surgery is well established. It has been reported that decreasing the surface dose reduces patient morbidity, especially facial weakness and numbness. The authors of this retrospective study examine patient data from a single center to determine if low-dose (≤ 14 Gy) GKS controls tumor growth as effectively as higher doses (> 14 Gy).MethodsBased on the formula for ellipsoid volumes, the tumor volumes were calculated using measurements from MR images obtained at follow up in patients treated at the authors' center. Follow-up data were available in 159 patients with a mean age of 59.5 ± 14.2 years at treatment. Fifty-six percent of the patients were women and 53.5% of the tumors were located on the right side of the brain. The mean tumor volume was 3.3 ± 4.3 cm3 with 10% of the tumors having volumes larger than 8 cm3. After GKS, smaller tumors (≥ 40% decrease in volume) were observed in 44.8% of patients treated with a low dose and in 48.8% treated with a high dose. Enlarged tumors (≥ 40% increase in volume) were seen in 5.2% of the patients receiving a low dose and 2.3% of those receiving a high dose. These differences were not statistically significant.Patients who had been followed up for longer than 5 years after treatment had median residual volumes of only 28.2% of the starting volume in the low-dose group and 26% in the high-dose group. This difference was statistically not significant.Conclusions No statistically significant differences were observed between tumors given low-dose radiation treatment and those given high-dose radiation treatment.

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Intradural Microsurgery and Extradural Gamma Knife Surgery for Hypoglossal Schwannoma: Case Report and Review of the Literature

min - Minimally Invasive Neurosurgery ◽

10.1055/s-2007-993206 ◽

2007 ◽

Vol 50 (6) ◽

pp. 374-378 ◽

Cited By ~ 9

Author(s):

A. Tucker ◽

H. Miyake ◽

M. Tsuji ◽

T. Ukita ◽

K. Nishihara ◽

...

Keyword(s):

Case Report ◽

Gamma Knife ◽

Gamma Knife Surgery ◽

Review Of The Literature ◽

Hypoglossal Schwannoma

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Gamma Knife surgery for low-flow cavernous sinus dural arteriovenous fistulas

Journal of Neurosurgery ◽

10.3171/2010.8.gks10977 ◽

2010 ◽

Vol 113 (Special_Supplement) ◽

pp. 21-27 ◽

Cited By ~ 5

Author(s):

Hyun Ho Jung ◽

Jong Hee Chang ◽

Kum Whang ◽

Jin Soo Pyen ◽

Jin Woo Chang ◽

...

Keyword(s):

Gamma Knife ◽

Cavernous Sinus ◽

Transarterial Embolization ◽

Gamma Knife Surgery ◽

Low Flow ◽

Close Monitoring ◽

Arteriovenous Fistulas ◽

Ocular Symptoms ◽

Dural Arteriovenous Fistulas

Object The purpose of this study was to assess the efficacy of Gamma Knife surgery (GKS) for treating cavernous sinus dural arteriovenous fistulas (CSDAVFs). Methods Of the 4123 GKSs performed between May 1992 and March 2009, 890 procedures were undertaken to treat vascular lesions. In 24 cases, the vascular lesion that was treated was a dural arteriovenous fistula, and in 6 of these cases, the lesion involved the cavernous sinus. One of these 6 cases was lost to follow-up, leaving the other 5 cases (4 women and 1 man) to comprise the subjects of this study. All 5 patients had more than 1 ocular symptom, such as ptosis, chemosis, proptosis, and extraocular movement palsy. In all patients, CSDAVF was confirmed by conventional angiography. Three patients were treated by GKS alone and 2 patients were treated by GKS combined with transarterial embolization. The median follow-up period after GKS in these 5 cases was 30 months (range 9–59 months). Results All patients experienced clinical improvement, and their improvement in ocular symptoms was noticed at a mean of 17.6 weeks after GKS (range 4–24 weeks). Two patients received embolization prior to GKS but did not display improvement in ocular symptoms. An average of 20 weeks (range 12–24 weeks) was needed for complete improvement in clinical symptoms. There were no treatment-related complications during the follow-up period. Conclusions Gamma Knife surgery should be considered as a primary, combined, or additional treatment option for CSDAVF in selected cases, such as when the lesion is a low-flow shunt without cortical venous drainage. For those selected cases, GKS alone may suffice as the primary treatment method when combined with close monitoring of ocular symptoms and intraocular pressure.

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Gamma knife surgery for vestibular schwannoma: 10-year experience of 195 cases

Journal of Neurosurgery ◽

10.3171/sup.2005.102.s_supplement.0087 ◽

2005 ◽

Vol 102 (Special_Supplement) ◽

pp. 87-97 ◽

Cited By ~ 19

Author(s):

Wen-Yuh Chung ◽

Kang-Du Liu ◽

Cheng-Ying Shiau ◽

Hsiu-Mei Wu ◽

Ling-Wei Wang ◽

...

Keyword(s):

Mr Imaging ◽

Gamma Knife ◽

Vestibular Schwannoma ◽

Tumor Volume ◽

Radiation Effect ◽

Gamma Knife Surgery ◽

Homogeneous Distribution ◽

Content Type ◽

Fine Print

Object. The authors conducted a study to determine the optimal radiation dose for vestibular schwannoma (VS) and to examine the histopathology in cases of treatment failure for better understanding of the effects of irradiation. Methods. A retrospective study was performed of 195 patients with VS; there were 113 female and 82 male patients whose mean age was 51 years (range 11–82 years). Seventy-two patients (37%) had undergone partial or total excision of their tumor prior to gamma knife surgery (GKS). The mean tumor volume was 4.1 cm3 (range 0.04–23.1 cm3). Multiisocenter dose planning placed a prescription dose of 11 to 18.2 Gy on the 50 to 94% isodose located at the tumor margin. Clinical and magnetic resonance (MR) imaging follow-up evaluations were performed every 6 months. A loss of central enhancement was demonstrated on MR imaging in 69.5% of the patients. At the latest MR imaging assessment decreased or stable tumor volume was demonstrated in 93.6% of the patients. During a median follow-up period of 31 months resection was avoided in 96.8% of cases. Uncontrolled tumor swelling was noted in five patients at 3.5, 17, 24, 33, and 62 months after GKS, respectively. Twelve of 20 patients retained serviceable hearing. Two patients experienced a temporary facial palsy. Two patients developed a new trigeminal neuralgia. There was no treatment-related death. Histopathological examination of specimens in three cases (one at 62 months after GKS) revealed a long-lasting radiation effect on vessels inside the tumor. Conclusions. Radiosurgery had a long-term radiation effect on VSs for up to 5 years. A margin 12-Gy dose with homogeneous distribution is effective in preventing tumor progression, while posing no serious threat to normal cranial nerve function.

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Intramedullary Teratoma: Case Report and Review of the Literature

Tumori Journal ◽

10.1177/030089169608200622 ◽

1996 ◽

Vol 82 (6) ◽

pp. 616-620 ◽

Cited By ~ 18

Author(s):

Riccardo Caruso ◽

Mariano Antonelli ◽

Luigi Cervoni ◽

Maurizio Salvati

Keyword(s):

Case Report ◽

Surgical Removal ◽

International Literature ◽

Review Of The Literature ◽

Personal Case

Aims and Background Intramedullary teratoma is an extremely exceptional tumor (5 cases), although a careful review of international literature has shown it to be more frequent (32 cases) than believed. Methods The authors present a personal case with some unusual aspects. Results Our case is unusual not only because it was diagnosed by MRI (only one case has been reported in the literature) but also because surgical removal of the tumor was apparently total (only 4 other cases have been described), with a long follow-up period (4.5 years) and excellent results, in clinical and neuroradiologic terms.

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