Clinical Application of Different Vertical Position Tests for Posterior Canal-Benign Paroxysmal Positional Vertigo-Cupulolithiasis

Abstract

BackgroundPosterior canal-benign paroxysmal positional vertigo-cupulolithiasis (PC-BPPV-cu) is a new and controversial type of benign paroxysmal positional vertigo (BPPV). At present, there are few relevant clinical studies as to whether the Half Dix-Hallpike test (Half D-HT) induces more obvious nystagmus than the Dix Hallpike test (D-HT) and straight head hanging test (SHH) in patients with PC-BPPV-cu.ObjectivesTo investigate the clinical characteristics of PC-BPPV-cu, and analyze the diagnostic significance of the Dix-Hallpike test (D-HT), Half D-HT, and straight head hanging (SHH) test in these patients.MethodsA total of 46 patients with PC-BPPV-cu were enrolled, and divided into two groups (N = 23): a group A (induction order: D-HT, Half D-HT, SHH) and a group B (induction order: Half D-HT, D-HT, SHH).ResultsAmong 46 patients with PC-BPPV-cu, the bilateral and unilateral abnormality rates of the disease side were 5 cases and 41 cases, respectively. There were significant differences in the proportion of torsional-upbeating nystagmus and upbeating nystagmus among the three headhanging positions in 46 patients with PC-BPPV-cu (P < 0.001). The slow phase velocity (SPV) of induced nystagmus at half D-HT supine position was slower than D-HT supine position (P < 0.05) and SHH supine position (P < 0.05). The nystagmus latency of D-HT supine position was significantly shorter than half D-HT (P < 0.05) and SHH (P < 0.05). PC-BPPV-cu patients were accompanied by 53.5% semicircular canal paresis, 69.6% audiological abnormalities, 76% cervical vestibular evoked myogenic potential (cVEMP), and 75% video head impulse test (vHIT) abnormalities, the concordance rates of the four detection methods were similar (χ2 = 0.243, P = 0.970).ConclusionsThe Half D-HT is simple and feasible, but might have a risk of false-negative diagnoses of the torsional-upbeating nystagmus and upbeating nystagmus. The D-HT is still a classic induction method for PC-BPPV-cu. The two complement each other and may aid in the diagnosis of PC-BPPV-cu patients. Future clinical applications of Half D-HT require extensive research to determine its diagnostic efficacy.

Posterior canal benign paroxysmal positional vertigo with long duration: Heavy or light cupula?

“…A nystagmic characterization of PSCC BPPV cupulolithiasis has been recently demonstrated, 4,6 and PSCC BPPV cupulolithiasis is receiving increasing attention in differential diagnosis for positional vertigo. The incidence of PSCC BPPV cupulolithiasis is considered much lower than that of canalolithiasis, and the proportion of cupulolithiasis cases in PSCC BPPV has been reported to be 6.4%–7.2%, 6,8 consistent with the proportion of 5.1% in the present study. Although many studies have supported the efficacy of canalith repositioning maneuvers (CRMs) in PSCC BPPV canalolithiasis, immediate resolution of BPPV after CRMs was not achieved in any of the patients with PSCC BPPV cupulolithiasis 9,22 .…”

“…PSCC BPPV can be diagnosed when upbeating and torsional nystagmus, which lasts for less than 1 min in most cases, is induced by a Dix‐Hallpike maneuver. 1 , 2 , 3 The concept of PSCC BPPV cupulolithiasis has been recently introduced, 4 , 5 , 6 , 7 , 8 , 9 and diagnostic criteria for PSCC BPPV cupulolithiasis were proposed by the Barany Society. 3 , 10 Cupulolithiasis in PSCC BPPV is distinguished from canalolithiasis in that the duration of positional nystagmus is longer than 1 min.…”

“…The authors reported that the axis angles of positional nystagmus were parallel to the ipsilateral PSCC and the contralateral anterior semicircular canal (ASCC) 6. Wang et al investigated whether the half Dix-Hallpike test induces more conspicuous nystagmus than the classical Dix-Hallpike test in PSCC BPPV cupulolithiasis, and reported that the occurrence rate of torsional-upbeating nystagmus was higher in the classical Dix-Hallpike test than in the half Dix-Hallpike test 8. The authors concluded that the classic Dix-Hallpike test is a better diagnostic test than the half Dix-Hallpike test for the diagnosis of PSCC BPPV cupulolithiasis because the half Dix-Hallpike test, although feasible and simple, could elicit a higher false negative rate.…”

The effectiveness of the modified Epley maneuver for the treatment of posterior semicircular canal benign paroxysmal positional vertigo

“…The G-Force swivel chair system (Figure 1) has a high accuracy and stability for nystagmus detection and recording, with spatial and temporal resolution of 640*480@60 Hz (16). The system we have developed also generates a BPPV virtual simulation model based on the patient's nystagmus data and repositioning maneuver parameters, which can be used to visually analyze the movement of the otolith in the semicircular canal (17).…”

“…Developed using Unity 3D software (version 2020.3) and the NVIDIA physics engine, the model simulated head movements and postural changes based on maneuver parameters (17). Real patient nystagmus data from the G-Force swivel chair system were used for calibration and validation, generating realistic and dynamic images of otolith movement in the semicircular canal under varying head positions (16,18,19).…”