Singular Neurectomy in the Management of Paroxysmal Positional Vertigo

Surgical Therapy in Intractable Benign Paroxysmal Positional Vertigo

OBJECTIVES: Benign paroxysmal positional vertigo (BPPV) is the most frequent vestibular disorder. Although it is easily cured with canal repositioning maneuvers for the majority of patients, it can be disabling in rare cases. For these patients, surgical solutions may be proposed. The aim of this article is to review the techniques used, the reported cases in the literature, and to discuss their indication in intractable BPPV.

STUDY DESIGN: Literature review.

MATERIALS AND METHODS: All the articles from 1972 to 2005 that discussed a specific surgical therapy in BPPV were reviewed. Many of them reported cases of operated patients and described original techniques. Some others are anatomic studies that discussed the two techniques used: singular neurectomy and posterior semicircular canal occlusion.

RESULTS: Singular neurectomy (posterior ampullary nerve transsection) and posterior semicircular canal occlusion are the 2 specific techniques used in intractable BPPV surgery. The numbers of operated cases are 342 and 97, respectively. These small numbers indicate that the procedures are difficult and risk compromising hearing and that a very small population of patients require surgical treatment of BPPV. The operated cases have been decreasing since the early 1990s because of improved management in BPPV. This article summarizes the techniques and their results and proposes a currently recommended practice of surgical therapy in BPPV as well as new insights into intractable BPPVs’ physiopathology.

Benign Paroxysmal Positional Vertigo: An Integrated Perspective

Benign paroxysmal positional vertigo (BPPV), the most common cause of dizziness, occurs in all age groups. It presents with vertigo on head movement, but in older patients presentation may be typical and thus accounting for a low recognition rate in the primary care setting. It may be recurrent in up to 50% of cases. BPPV is associated with displacement of fragments of utricular otoconia into the semicircular canals, most commonly the posterior semicircular canal. Otoconia are composed of otoconin and otolin forming the organic matrix on which calcium carbonate mineralizes. Otoconia may fragment with trauma, age, or changes in the physiology of endolymph (e.g., pH and calcium concentration). Presentation varied because otoconia fragments can be displaced into any of the semicircular canals on either (or both) side and may be free floating (canalolithiasis) or attached to the cupula (cupulolithiasis). Most cases of BPPV are idiopathic, but head trauma, otologic disorders, and systemic disease appear to be contributory in a subset. Positional maneuvers are used to diagnose and treat the majority of cases. In rare intractable cases surgical management may be considered. A strong association with osteoporosis suggests that idiopathic BPPV may have diagnostic and management implications beyond that of a purely otologic condition.

Long-term results of posterior semicircular canal occlusion for intractable benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is a common condition which is usually managed conservatively, surgical intervention being recommended only for those small number of patients in whom it becomes persistent and incapacitating. The results of surgery in 13 patients who underwent posterior semicircular canal occlusion for intractable (> 12 months duration) and incapacitating BPPV are presented with special emphasis on their long-term follow-up. The mean follow-up was 66 months (range, 29-119 months). All patients reported complete and immediate resolution of their positional vertigo, which has been maintained in the long term. Most patients, however, reported some postoperative transient unsteadiness which lasted up to 4 weeks. All patients developed a transient mild conductive hearing loss secondary to a middle ear collection, which usually resolved within 4 weeks. Five patients developed a transient mild high frequency sensorineural hearing loss which resolved in all cases within 6 months. There were no reports of sensorineural hearing loss nor tinnitus in the long term. All patients believed that the operation was beneficial and would undergo it again. Our findings indicate that posterior semicircular canal occlusion is an effective and safe operation in the long term and is the procedure of choice for intractable and incapacitating BPPV rather than singular neurectomy.

A review of management of benign paroxysmal positional vertigo by exercise therapy and by repositioning manoeuvres

Benign paroxysmal positional vertigo (BPPV) is a common condition that often resolves spontaneously, but can cause significant distress to a patient. Management of this condition includes no intervention, medication, surgery, physical exercises and more recently 'particle repositioning' manoeuvres. Repositioning manoeuvres aim to relocate free-floating particles from the posterior semicircular canal into the utricle where they will no longer cause vertiginous symptoms. This article describes the different exercises and repositioning manoeuvres in use and examines their efficacy. In the light of this review a management strategy for BPPV is suggested.

Surgical anatomy of the singular nerve

Rare cases of chronic persistent positional vertigo do not respond to physiotherapy. For the treatment of these cases Gacek suggested singular nerve neurectomy as a new surgical procedure. The aim of the present study was to investigate the surgical anatomy of the singular nerve in order to evaluate the exact topography. In 25 cadaver temporal bones the posterior ampullary ("singular") nerve was prepared. The topographical correlation between singular nerve, posterior semicircular canal, and the round window membrane was evaluated. The average length of the nerve was 4.2 mm, its diameter 0.6 mm. The shortest distance between singular nerve and round window membrane was 0.7 mm in average, the nerve could be detected at a depth of 1.3 mm. The transtympanal access was impossible in 7 of 25 cases either because of its close relation to the round window or its direct course towards the ampulla. In only 5 of 25 cases was the nerve located sufficiently inferior in the round window niche for neurectomy. Thus, transtympanal singular nerve neurectomy can be performed only in selected cases. The presented data are helpful for preoperative and intraoperative decisions.