Functional magnetic resonance imaging (FMRI) is a new noninvasive technique for imaging cerebral function. Studies of the human central auditory pathway examined responses in eight normal hearing volunteers following auditory stimuli, including narrative speech and pure-tone audiometry. The activation demonstrated by FMRI is modeled on an increase in regional blood flow with increased neuronal activity. The FMRI signals represent deoxyhemoglobin concentration changes in capillaries within the region of the brain that is activated. Brain activation was imaged in the superior temporal gyrus during text reading and pure tones. Activation in both text and pure-tone presentation did not vary with the intensity of the auditory stimulus and elicited a dominant response in the left temporal lobe. These observations demonstrate the capability of FMRI to correlate anatomic and functional relationships in the human central auditory pathway.

The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding.

Sudden sensorineural hearing loss is a well recognized phenomenon in otologic practice with both viral and vascular etiologies being supported. However, sudden hearing loss as a complication of non‐otologic surgical procedure is a seldom reported and rare phenomenon. Five cases of unilateral sudden sensorineural hearing loss which are time related and probably causally related to non‐otologic surgery are presented. Two cases underwent open heart surgery and support previous reports of hearing loss secondary to cardiopulmonary bypass procedures. Three noncardiac cases are also reviewed. None of these patients had prior otologic disease which would predispose to a sudden hearing loss, and no intraoperative or postoperative complication was specifically noted as a cause of the hearing loss. The literature is reviewed and attention is drawn to the problem. We wish to encourage further reports and to recommend early identification and treatment in those cases related to cardiopulmonary bypass.

We present our 2-year experience with a contrast enhancement agent in magnetic resonance imaging (MRI) examining facial nerve pathology. Characteristics of the agent gadolinium diethylenetriamine pentaacetic acid are reviewed. The radiographic capability to differentiate pathologic vs. normal facial nerves based on enhancement and a change in signal intensity generated by the nerve is demonstrated. Experience with facial nerve disorders including Bell's palsy, facial nerve neuromas, a facial nerve graft site, postoperative facial paralysis, and traumatic facial paralysis is presented. The ability to image the facial nerve in Bell's palsy provides an entirely new means of examining this disorder, and its implications are discussed. The ability to enhance the paralyzed facial nerve in the temporal bone after posterior fossa surgery supports a previously held concept as to the pathophysiology of this problem.

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