The dilemma of early postoperative magnetic resonance imaging: when efficiency compromises accuracy: case report.

Abstract

Postoperative magnetic resonance imaging (MRI) is critical to the clinical decision-making process for patients undergoing resection of intracranial tumors. The accuracy of immediate postoperative MRI in determining the presence of residual disease following intracranial tumor resection, however, has not been studied. A 57-year-old man underwent an uncomplicated retrosigmoid craniotomy for the resection of a cystic vestibular schwannoma. Immediate gadolinium-enhanced postoperative MRI, performed within 1.5 hours of surgery, was notable for a plaquelike, lobular, avidly enhancing collection with MRI characteristics consistent with fluid density extending from the porus acusticus into the cerebellopontine angle. This anomalous lesion disappeared upon repeat imaging 48 hours later, and the patient had no attributable clinical sequelae. He was discharged home without issues within 12 hours of repeat imaging. We demonstrate here that immediate postoperative, gadolinium-enhanced MRI scans after tumor resection may result in avid enhancement in the region of surgical manipulation, likely due to leakage of gadolinium chelates into the subarachnoid space from residual compromise of the blood-brain barrier immediately following surgical manipulation. Early imaging is no longer routinely performed at our institution unless otherwise clinically indicated. FLAIR, fluid-attenuated inversion recoveryIAC, internal auditory canal.