Acta Otolaryngol (Stockh) 1998; 118: 455 – 460 The Management of Horizontal-canal Paroxysmal Positional Vertigo DANIELE NUTI 1 , GIUSEPPE AGUS 2 , MARIA-TERESA BARBIERI 1 and DESIDERIO PASSALI 1 From the 1 Department of Otolaryngology, Uniersity of Siena, Italy and the 2 Department of Otolaryngology, Uniersity of Cagliari, Italy Nuti D, Agus G, Barbieri M-T, Passali D. The management of horizontal -canal paroxysmal positional ertigo. Acta Otolaryngol (Stockh) 1998; 118: 455 – 460. Horizontal-canal paroxysmal positional vertigo (HC-PPV) is a vestibular syndrome due to canalolithiasis of the horizontal canal. The more common posterior-canal paroxysmal positional vertigo has a well defined and effective therapy, while there have been few reports on physical therapy for HC-PPV, and these have been tried in relatively few patients. We report the results of two different types of treatment of HC-PPV in 92 patients. A group of 21 untreated patients acted as a control group. One method, known as forced prolonged position (FPP), proposes liberating the affected canal by gravitation, and involves having the patient lie on the healthy side for many hours. The other method (the barbecue rotation) is a liberatory manoeuvre which proposes to expel the otoconia from the canal by rotating the patient 270° around the longitudinal axis of the body in rapid steps of 90°. FPP was successful in more than 70% of our patients; the barbecue rotation had slightly less successful but more immediate results. Both methods enable otoconial debris to migrate into the posterior canal. We suggest treating all patients with the two methods in succession. Key words : canalolithiasis, horizontal semicircular canal, paroxysmal positional ertigo, physical therapy. INTRODUCTION Paroxysmal positional vertigo (PPV) is the most com- mon peripheral vestibular disorder. In most cases it is due to canalolithiasis of the posterior semicircular canal (PC). The existence of a PPV due to canalolithi- asis of the horizontal canal (HC) was also recently proposed (1, 2). HC-PPV differs from PC-PPV mainly in that the vertigo is more intense, it is principally caused by rotary movements of the head or body in supine position, and nystagmus is horizon- tal instead of vertical-torsional. In most cases, rota- tion to the pathological side from supine position causes a very intense horizontal nystagmus beating towards the undermost ear (geotropic); when the patient is rolled to the other, healthy side, there is a less intense horizontal nystagmus again beating to- wards the undermost ear. Less frequently, the syn- drome presents with horizontal nystagmus beating towards the uppermost ear (apogeotropic) and is usually more intense when the affected ear is upper- most (2, 3). In some patients, either type of nystag- mus may occur on different occasions (3). The clinical findings can be explained by displace- ment of otoconia in the HC. Otoconial debris moving under gravity may cause deflections of the cupula and excitatory or inhibitory nystagmus. In the geotropic variant, when the patient is rolled towards the af- fected side, the particles fall towards the ampulla which, acting as a plunger, causes a very intense geotropic nystagmus; rotation of the head to the other side makes the debris and the cupula move in the opposite direction, provoking an inhibitory nys- tagmus, less intense and again geotropic. In the apo- geotropic variant, the different direction of the nystagmus may be due to the fact that the starting position of the otoconial debris in the long arm of the canal is much closer to the ampulla (3). The management of PC-PPV relies on positioning manoeuvres designed to free the affected canal of debris. The most frequently-used techniques are those proposed by Epley (4) and Semont et al. (5), both of whom have a high success rate. There have been few reports on physical therapy for HC-PPV. In 1993 Baloh et al. (6) tried to liberate the affected canal by a method consisting of a 180° rotation from supine to prone position, towards the unaffected ear. Although the physiopathological basis of this manoeuvre was convincing, it failed to stop positional vertigo in the two patients so treated. In 1994 Vannucchi et al. (7) proposed to treat this syndrome by a very simple method: the pathological ear is identified and the patient lies, healthy side down, for about 12 h. With this method, known as ‘‘forced prolonged position’’ (FPP), the authors ob- tained excellent results in the 35 patients treated (8). In the same year, Thomas Lempert suggested treat- ing HC-PPV with a liberatory manoeuvre he called the ‘‘barbecue rotation’’. The manoeuvre consists of a single 270° rotation around the supine patient’s yaw (longitudinal) axis, performed in rapid steps of 90° at 30 s intervals (9). Two patients obtained immediate relief by this method. The same rehabilitation treat- ment was used by Epley (10), and a similar manoeu- vre, with 360° rotation, is also recommended by Baloh (11, 12). The aim of this study is to verify the efficacy of two different methods of treating HC-PPV. In order to have a large patient population, a prospective study was performed in the ENT departments of Siena and Cagliari universities. © 1998 Scandinavian University Press. ISSN 0001-6489