Gamma Knife radiosurgery for low-grade tectal gliomas

• Published in: Acta neurochirurgica 2015-02, Vol.157 (2), p.247-256
• Main Authors: El-Shehaby, Amr Mohamed Nageeb, Reda, Wael Abdel Halim, Abdel Karim, Khaled Mohamed, Emad Eldin, Reem Mohamed, Esene, Ignatius Ngene
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Astrocytoma - pathology; Astrocytoma - surgery; Brain Stem Neoplasms - pathology; Brain Stem Neoplasms - surgery; Child; Clinical Article - Brain Tumors; Female; Glioma - pathology; Glioma - surgery; Humans; Hydrocephalus - surgery; Interventional Radiology; Male; Medicine; Medicine & Public Health; Middle Aged; Minimally Invasive Surgery; Neoplasm Grading; Neurology; Neuroradiology; Neurosurgery; Radiosurgery - methods; Surgical Orthopedics; Tectum Mesencephali - pathology; Tectum Mesencephali - surgery; Treatment Outcome; Tumor Burden; Ventriculostomy; Young Adult
• ISSN: 0001-6268; 0942-0940
• DOI: 10.1007/s00701-014-2299-y

Background Tectal gliomas are present in a critical location that makes their surgical treatment difficult. Stereotactic radiosurgery presents an attractive noninvasive treatment option. However, tectal gliomas are also commonly associated with aqueductal obstruction and consequently hydrocephalus. This necessitates some form of CSF diversion procedure before radiosurgery. The aim of the study was to assess the efficacy and safety of Gamma Knife radiosurgery for tectal gliomas. Patients and methods Between October 2002 and May 2011, 11 patients with tectal gliomas were treated with Gamma Knife radiosurgery. Five patients had pilocytic astrocytomas and six nonpilocytic astrocytomas. Ten patients presented with hydrocephalus and underwent a CSF diversion procedure [7 V-P shunt and 3 endoscopic third ventriculostomy (ETV)]. The tumor volume ranged between 1.2–14.7 cc (median 4.5 cc). The prescription dose was 11–14 Gy (median 12 Gy). Results Patients were followed for a median of 40 months (13–114 months). Tumor control after radiosurgery was seen in all cases. In 6/11 cases, the tumors eventually disappeared after treatment. Peritumoral edema developed in 5/11 cases at an onset of 3–6 months after treatment. Transient tumor swelling was observed in four cases. Four patients developed cysts after treatment. One of these cases required aspiration and eventually disappeared, one became smaller spontaneously, and two remained stable. Conclusion Gamma Knife radiosurgery is an effective and safe technique for treatment of tectal gliomas. Tumor shrinkage or disappearance after Gamma Knife radiosurgery may preclude the need for a shunt later on.