Title: Role of MRI in Evaluation of Posterior Fossa Tumours
Authors: Dr Chandresh Bharada, Dr Bhoomi Angirish, Dr Harshad Shah, Dr Rasesh Vyas
DOI: https://dx.doi.org/10.18535/jmscr/v5i6.219
Abstract
Introduction: Magnetic resonance imaging has been one of the most spectacular advances and has practically revolutionized the diagnosis of brain tumours. MRI scan is more accurate in diagnosing infratentorial brain tumours than CT. Presence of various characteristics like hemorrhage, necrosis, edema, mass effect and neovascularization are all better evaluated with MRI than with CT scan. Hence, MRI is generally the investigation of choice in characterization of them.
Materials and Methods: The study was conducted on 60 patients in the department of Radiodiagnosis, C.U. Shah Medical College, Surendranagar , Gujarat for a period of 24 months from Feburary 2015 to Feburary 2017.
Observations: Most of patients were above 50 years of age with largest age group between 51-60 years. Cerebellum was most commonly involved part of brain in 27 patients. Most common pathological subtypes were metastases. Next most common pathological type of tumour in the present study was schwannoma. Other tumours included ependymoma, arachnoid cyst, epidermoid cyst, pilocytic astrocytoma and glioma.
Conclusion: MRI showed exquisite sensitivity in detecting haemorrhage, necrosis, edema as well as extension of the tumours to other sites and internal auditory canal in case of acoustic schwannoma. Advanced MRI techniques like DWI and MRS helped to diagnose all suspected malignant lesion non-invasively with fair accuracy which was not possible with CT. The salient advantages of MRI thus are its ability to tissue characterize the lesion, detect haemorrhage, necrosis and edema accurately, ability to differentiate malignant from benign lesions non-invasively and most importantly lack of ionizing radiation.
Keywords: Posterior fossa, Metastasis, Schwannoma, Meningioma.
