Assessment of Large Tumor Shrinkage Using Hypofractionated Gamma Knife Radiosurgery

Abstract

Background:    The Gamma Knife (GK) is a radio surgical method to treat malignant and benign brain tumours, atrioventricular malformations (AVM), and functional disorders.
Objective:    To investigate the tumor shrinkage after six months of GK with hypofractionation.
Methods:    A study at Dr. Saad Al-Witry Hospital for Neurosciences and Al-Altaj Hospital involved 50 patients with large brain tumors. Each patients underwent a magnetic resonance imaging and computed tomography images before and after treatment. 
Results:    The mean dose distribution was higher in metastasis. After irradiation, gliosis around the tumor was observed, with 86% showing a positive response to radiation treatment. The results of tumor shrinkage were classified according to the number of treatment fractions, with highly significant shrinkage observed in those treated in three fractions and those treated after four fractions.
Conclusion:    The hypo fractionated GK appears to be a viable and effective method of treating various brain tumors that are benign or malignant. The method has a favorable outcome that involves both a decrease in tumor size and a minimum of side effects. 
Keywords:    Large brain tumor, volumetric change, gradient index (GI), gamma knife, stereotactic
Citation:    Kadhem MH, Ahmed RS, Hamandi YMH. Assessment of large tumor shrinkage using hypofractionated gamma knife radiosurgery. Iraqi JMS. 2025; 23(2): 222-228. doi: 10.22578/IJMS.23.2.4