Diagnostic accuracy of magnetic resonance imaging in detection of acoustic neuroma

ABSTRACT

Acoustic neurojna is the most frequent benign tumour at cerebellopontine angle. It accou-ntsfor 8 - 10% of all primary intracranial tumours and 80% of Cerebellopontine angle tumours.[2] Meningioma constitutes 5 - 10% of Cerebellopontine angle tumors, with rare tumours constituting only a small percentage out of which epidennoid cyst is the most frequent. This study was performed to determine the diagnostic accuracy of magnetic resonance imaging in the detection of acoustic neuroma that is taking histopathology a gold standard. It is a cross sectional study conducted in the Department of Diagnostic Radiology, Lahore General Hospital, Lahore from 14-07-2012 to 14-07-2013. The study comprised of 55 patients with clinical suspicion of acoustic neuroma. Magnetic resonance imaging on a 1.5-T Philips whole body magnetic resonance system was performed. The cases were operated and histopathological results were recorded. The results of magnetic resonance imaging and histopathology were compared taking histopathology as gold standard. Out of 55 patients, 43 patients [78.2%] had acoustic neuroma on magnetic resonance imaging. After comparison of results of magnetic resonance imaging with histopathology, the sensitivity, specificity, positive piedictive value, negative predictive value and diagnostic accuracy of magnetic resonance imaging were 97.7%, 91.7%, 97-7%, 91-7% and 96.4% respectively. Magnetic resonance imaging is a highly accurate, non-invasive, safe and convenient imaging modality for the evaluation of acoustic neuroma and is valuable for guiding surgical biopsies thereby decreasing unnecessary intervention. It allows detection of small tumors which is very useful in tumor characterization and plays an integral role m early detection, planning management and estimating patient's prognosis