[Vascular loop. A contributing factor to vascular cerebellopontile syndrome].

Modern diagnostic methods such as brainstem-evoked response audiometry and CT scanning with positive and negative contrast enhancement represent a major advance in the diagnostic evaluation even of small acoustic neuromas. However difficulties arise in differentiation between tumours and other cerebellopontine angle lesions, as shown by means of a case report. An arterial loop of the anterior inferior cerebellar artery (AICA) between the facial and the eighth cranial nerve was the cause of progredient neural hearing loss, peripheral vestibular dysfunction and hemifacial spasm. Vascular decompression was performed with total relief of spasm and partial restitution of hearing. In differential diagnosis of the pathology of the cerebellopontine angle region and the internal auditory canal the clinical symptoms are important.