Multivoxel proton MRS for differentiation of radiation-induced necrosis and tumor recurrence after gamma knife radiosurgery for brain metastases.

摘要: Multivoxel proton magnetic resonance spectroscopy (MRS) was used for differentiation of radiation-induced necrosis and tumor recurrence after gamma knife radiosurgery intracranial metastases in 33 consecutive cases. All patients presented with enlargement the treated lesion, increase perilesional brain edema, aggravation or appearance neurological signs symptoms on average 9.3 ± 4.9 months primary treatment. Metabolic imaging defined four types lesions: pure (11 cases), partial (10 peritumoral (1 case). In 1 patient, diagnosed 9 radiosurgery; however, identified 6 later. With exception midline shift, which found to be more typical (P < 0.01), no one clinical, radiologic, radiosurgical parameter either at time treatment deterioration showed a statistically significant association type lesion. Proton MRS-based diagnosis confirmed histologically all surgically (7 cases) corresponded well clinical course others. conclusion, multivoxel MRS is an effective diagnostic modality identification that can monitoring metabolic changes neoplasms It also helpful brain, may have important medicolegal implications.