 von Hippel-Lindau disease vHL is a hereditary multi-system disease requiring life-long prophylactic surveillance. Affected individuals are predisposed to development of tumors and cysts in multiple organs. In recent years, it has become apparent that endolymphatic sac tumors ELSTs, aggressive tumors of the petrous bone, occur in up to 16 of vHL patients. ELST can lead to severe and progressive hearing loss and vertigo as well as other audio-vestibular and neurological symptoms. However, surgical excision of tumors can preserve patients pre-operative hearing level, and eliminate most other audio-vestibular symptoms. As even small ELSTs have been shown to lead to sudden and irreversible deafness, timely diagnosis of ELSTs is essential to prevent severe audio-vestibular morbidity in ELST patients. Several recommendations of ELST surveillance in vHL patients have been proposed; some suggest that diagnostic tests for ELST should be done only in vHL patients with subjective audio-vestibular symptoms, while others recommend audiological examinations or MRI of the inner ear in all vHL patients as a screening tool. However, there has not previously been much focus on specification of screening strategies, and it is not known, which is the most optimal approach. The results of a national study of ELST surveillance among Danish vHL patients indicated that specific patterns of audiologic parameters in patients with ELSTs, indicating that a distinct audiologic pattern may be typical in ELST development, perhaps even before the ELST is detectable on MRI. However, a larger study of audiologic parameters in vHL patients with and without diagnosed ELSTs is needed in order to fully investigate such a model and its use in early ELST detection. 