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A Clinical Approach to Abnormal Eye Movements
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
The horizontal canal variant of BPPV is elicited by the supine roll test, in which the patient's head is first flexed forward about 30° to align the horizontal canal with the earth vertical, and then turned about 90° to each side. Two types of positional nystagmus can be observed in horizontal BPPV, that is geotropic and apogeotropic. In the geotropic type, the nystagmus beats to the ground. In the supine head roll test, when head is turned to the right, the nystagmus beats to the right. When the head is turned to left, the nystagmus beats to the left. In the apogeotropic type, the nystagmus beats away from the ground. In the supine head roll test, when head is turned to the right, the nystagmus beats to the left. When the head is turned to left, the nystagmus beats to the right. The geotropic BPPV is due to canalolithiasis, whereas the apogeotropic BPPV is due to cupulolithiasis and is more persistent.
Vertigo
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
Christopher C. Glisson, Jorge C. Kattah
Episodic triggered vertigo: The most common triggers are the traditional positional maneuvers (Dix–Hallpike)7 and head roll.10,11 The examiner finds absent nystagmus in straight-ahead gaze, and within a few seconds upon completion of the positional trigger maneuver, the patient develops paroxysmal nystagmus, usually upbeat/torsional, geotropic for the most commonly affected posterior SCC.12,13 The nystagmus will be horizontal during the head roll maneuver in patients with horizontal canal BPPV (h-canal BPPV), with two main variants: 1. Geotropic (free-floating particles in the canal), where the fast phase of the triggered horizontal nystagmus (h-nystagmus) matches the direction of the head roll, and 2. Apogeotropic (particles attached to h-canal cupula)7 in which the nystagmus fast phase beats opposite to the head roll position.11 On rare occasions, a primary position horizontal nystagmus in straight gaze “may still represent horizontal canal BPPV” (pseudospontaneous nystagmus). It is recognized by a change in the h-nystagmus direction with the head pitch forward; thus, it is advisable to perform this step in any patient with spontaneous horizontal nystagmus.14
Common otology viva topics
Published in Joseph Manjaly, Peter Kullar, Advanced ENT Training, 2019
Nystagmus is horizontal, and either geotropic (towards the ground) or apogeotropic (away from the ground), depending on whether the debris is within the long arm or short arm of the canal, respectively, as well as, which ear is downmost and therefore being stimulated.
Vertical “pseudospontaneous” nystagmus in a patient with posterior canal BPPV: case report
Published in Acta Oto-Laryngologica Case Reports, 2021
Bernardo Faria Ramos, Renato Cal, Pedro Luiz Mangabeira Albernaz, Francisco Zuma e Maia
In order to explain the evoked nystagmus in patients with BPPV it is first necessary to consider the location of the otoliths in the starting position [2]. In posterior canal BBPV the debris are usually located in the most inferior part of the ampullary arm of this canal, next to the ampulla. When patients are submitted to the Dix Hallpike test to the affected side, the otoliths fall away from the ampulla, emerging in an ampullofugal excitatory endolymphatic flow. The posterior canal excitation activates the ipsilateral superior oblique and the contralateral inferior rectus muscles. The primary action of these muscles are respectively, incyclotorsion and depression of the eyes. Hence, the provoked nystagmus (fast phase) is geotropic vertical torsional with the vertical component upwards and the upper pole of the eye beating to the undermost ear.
A prospective randomized controlled study of Li quick repositioning maneuver for geotropic horizontal canal BPPV
Published in Acta Oto-Laryngologica, 2018
Jinrang Li, Shizhen Zou, Shiyu Tian
Presently, several types of repositioning maneuvers are available for treating different forms of canal BPPV. For HC-BPPV, which has the second highest incidence among all forms of BPPV, the primary repositioning treatment procedures are the barbecue, Gufoni and forced prolonged positioning maneuvers [1,7]. From research studies and clinical practice, we have also found that the Semont maneuver, which is used for treating PC-BPPV, enables the otoliths that are floating in the posterior canal to reposition into the utricle through rapid changes in the patient’s position, and the method is characterized by short treatment duration [8]. Based on the theory and characteristics of the Semont maneuver, Li et al. [9] developed a novel repositioning maneuver for the treatment of HC-BPPV, which was termed the ‘Li quick positioning maneuver for HC-BPPV’ (Li maneuver for short in this article). According to the direction of the nystagmus, the HC-BPPV has two types: geotropic and apogeotropic, but the geotropic HC-BPPV is very common. So in this study, the efficacy of the Li and barbecue maneuvers for the treatment of geotropic HC-BPPV was compared in a randomized controlled study, in order to further confirm the Li maneuver’s clinical efficacy for treating geotropic HC-BPPV.
Effect of intratympanic steroid injection in light cupula
Published in Acta Oto-Laryngologica, 2018
Jin Su Park, So Yean Kim, Min-Beom Kim
Although Geotropic DCPN in HC canalolithiasis is transient; it usually ceases within 1 min and can be fatigued, some patients have been reported with positional vertigo who display a persistent (over 1 min) geotropic DCPN with a null point (when the head is slightly turned to the affected side in the supine position until the HC cupula is aligned with the plane of the gravitational vector, the nystagmus stops; the direction changes with further head-turn) and without latency or fatigability. To explain this variant of geotropic DCPN, the ‘light cupula’ mechanism was introduced [2–4]. Under normal conditions, the specific gravity of the cupula is almost the same as that of endolymph. However, if the cupula becomes relatively lighter than the endolymph for any reason, the cupula increases in buoyancy which results in geotropic positional nystagmus [3].