Abnormal Rhomboid Lip and Choroid Plexus Should be Valued in Microvascular Decompression for Vestibulocochlear Diseases.

Background: Surgical outcomes for functional vestibulocochlear diseases vary, and the influencing factors are not fully understood. The role of a rhomboid lip (RL) and choroid plexus (CP) in microvascular decompression (MVD) of the vestibulocochlear nerve has not been studied. This study aims to evaluate the surgical efficacy of MVD for vestibulocochlear diseases, with and without addressing the RL and CP, to enhance our understanding of their etiology.

Methods: A total of 15 patients who underwent MVD for the vestibulocochlear nerve between 2013 and 2022 were retrospectively identified and followed up. The patients were classified into 4 categories: vestibular paroxysmia (VP), benign positional paroxysmal vertigo (BPPV), and Meniere disease (MD). The fourth was a "tinnitus" group. The relief of symptoms, recurrence, satisfaction after surgery, available relevant imaging studies, and intraoperative observation data were evaluated.

Results: Following MVD, 6 of the 7 patients in the VP group, the 1 patient in the BPPV group, and 1 of 2 patients in the MD group were completely relieved of vertigo. The seventh VP patient showed significant improvement. The 5 patients in the "tinnitus" group remained unchanged. Retrospectively, 4 patients from the VP, BPPV, and MD groups who underwent RL incision and CP excision were also free of vertigo, although vascular compression was not confirmed in these cases.

Conclusions: MVD is generally considered a useful treatment for VP and could also be effective in managing recurrent vertigo caused by BPPV and MD. Our results highlight the potential role of an abnormal RL and CP in the development of vertigo symptoms. Patients presenting with "tinnitus" require further investigation and might not be suitable for MVD.