Current diagnostic procedures for diagnosing vertigo and dizziness

Quantitative vestibular assessment: The development and validation of a novel, remote video head impulse test against in-clinic measurements

Objectives

To develop a novel remote head impulse test (rHIT), and to provide preliminary data validating the rHIT vestibular-ocular reflex (VOR) gains against the in-clinic vHIT.

Methods

A convenience sample of 10 patients referred for vestibular assessment at our institution was recruited. In-clinic vHIT was used to quantify lateral VOR gains. Patients subsequently underwent an rHIT protocol, whereby patients performed active, lateral head rotations while their eyes and heads were recorded using a laptop camera and video-conferencing software. The vHIT and rHIT VOR gains were compared using paired t-tests, and a Pearson correlation coefficient between the gains was calculated. Absolute accuracy, sensitivity, and specificity of the rHIT were additionally calculated.

Results

Of the 10 patients recruited, 4 were male, and the average ± standard deviation (SD) age was 61.4 ± 15.3 years. As determined by the vHIT, 2 patients had normal bilateral VOR gains, 6 with unilateral vestibular hypofunction, and 2 with bilateral vestibular hypofunction. The correlation between the rHIT and vHIT gains was 0.73 (p < .001). The rHIT exhibited an absolute accuracy of 75.0%, sensitivity of 70.0%, and specificity of 80.0%. When ears had a vHIT VOR gain less than 0.40, the rHIT exhibited 100.0% accuracy. Conversely, 60.0% of deficient ears with vHIT VOR gains greater than 0.40 were incorrectly categorized by the rHIT.

Conclusion

The rHIT may be better suited for detecting more severe vestibular deficiencies. Future iterations of the rHIT should aim to increase the video frame-rate capabilities to detect subtler VOR impairments.

Level of Evidence

4.

Effects of saccade delay, side of deficit, and training on detection of catch-up saccades during head-impulse test in virtual-reality-enhanced mannequin

In this study, a training simulator for the examination of dizzy patients based on a virtual-reality-enhanced mannequin (VREM) was developed to evaluate the detection of catch-up saccades during head impulse test (HIT) and the effect of training in VREM. For novices (n = 35), 2 trials were conducted before and after a training session. Experts (n = 7) were submitted to an evaluation session. In each trial, a left or a right horizontal canal deficit with an overt catch-up saccade (delay between 110 and 320 ms) was randomly presented. Participants scored the difficulty in performing the maneuver, in recognizing the saccades, and the self-confidence in the diagnosis using a visual analogue scale (VAS). Saccade delay significantly influenced the performance. Training significantly improved the sensitivity in the residents (69.1% before to 97.9% after the training, p < 0.001, Fisher's exact test, n = 560 tests), surpassing experts' performances (p < 0.001, versus 87% in experts, Fisher's exact test). The specificity also increased to the expert level (78% before to 95% after the training, and 95% in experts, p < 0.001, Fisher's exact test). The VAS showed a decrease difficulty to execute the HIT, with an increase in the confidence after training. VREM improved the HIT execution performance and the confidence in novice practitioners.

A prospective study on the application of HINTS in distinguishing the localization of acute vestibular syndrome

BACKGROUND

Acute vestibular syndrome (AVS) is a common clinical syndrome in neurology clinics and emergency department. Canonical standard for AVS diagnosis requires the presence of persistent vertigo for more than 24 h. HINTS (head impulse-nystagmus-test of skew) is an emerging scheme in the diagnosis of AVS. In this prospective study, we evaluated the specificity and sensitivity of HINTS in distinguishing between central and peripheral AVS.

METHODS

A cohort of 239 cases with complete clinical record was recruited in the study. All patients completed emergency brain CT examination to exclude hemorrhagic stroke. HINTS examination was conducted to distinguish between central AVS and peripheral AVS, and all patients completed head MRI, BAEP and vestibular function examinations within one week. Patients diagnosed as central AVS were subject to angiography (CTA/MRA/DSA), and patients with peripheral AVS were considered for a 3-month follow-up to correct the initial diagnosis.

RESULTS

Patients with central AVS were associated with an elder age, higher incidences of hypertension, atrial fibrillation, family history of stroke and previous history of stroke. Posterior circulation cerebral infarction, vestibular migraine and cerebellitis were the dominant diseases associated with central AVS. The sensitivities of HIT, GE, and TS in the diagnosis of central AVS were 73.5%, 61.2%, and 26.5%, and the specificities were 97.9%, 92.6%, and 93.2% respectively.

CONCLUSIONS

The sensitivity of HINTS for central AVS diagnosis is 89.8% and the specificity is 84.2%. HINTS is an easy-to-operate, low-cost, high-sensitivity and specific examination technique, which is practical in neurology outpatient clinics and emergency departments.

Changing Paradigm for Vertigo/Dizziness Patients: a Retrospective Before-After Study from Tertiary Hospitals in Northwestern China

BACKGROUND

Single disciplinary management of patients with vertigo and dizziness is an important challenge for most physicians in China.

OBJECTIVE

To assess the impact of a new paradigm of practice (Clinic for Vertigo and Dizziness, CVD) performed by a multidisciplinary team (MDT) on diagnostic spectrum, medical costs, and patient satisfaction.

DESIGN

Retrospective before-after study.

PARTICIPANTS

Sample of 29,793 patients with vertigo/dizziness as primary complaint.

MEASURES

Changes in diagnostic spectrum, medical costs, and patient satisfaction before and after the establishment of a CVD based on a 4-year database in three tertiary hospitals in northwestern China.

KEY RESULTS

The most common diagnoses of patients with vertigo and dizziness were Meniere's disease (25.77%), cervical disease (25.00%), cerebral vascular disease (13.96%), vestibular syndrome (10.57%), and other etiologies (6.34%) before the CVD establishment. In contrast, after the CVD establishment, the most common diagnoses were BPPV (23.92%), vestibular migraine (15.83%), Meniere's disease (14.22%), CSD/PPPD (11.61%), and cerebral vascular diseases (4.45%). Extended implementation of a structured questionnaire for vertigo/dizziness and vestibular-oriented examinations (nystagmus, positional tests, HINTS) at the CVD resulted in a remarkable decline in the utility of CT/MRI and X-ray examination (p < 0.001). Meanwhile, medical costs in patients with vertigo/dizziness dropped by 11.5% (p < 0.001), with a significant improvement in patient satisfaction after the establishment of CVD (p < 0.001).

CONCLUSIONS AND RELEVANCE

Our study suggested that the MDT paradigm of CVD practice may facilitate the medical management of patients with vertigo/dizziness and improve patient satisfaction.

Preferential Cochleotoxicity of Cisplatin

Cisplatin-induced ototoxicity in humans is more predominant in the cochlea than in the vestibule. Neither definite nor substantial vestibular dysfunction after cisplatin treatment has been consistently reported in the current literature. Inner ear hair cells seem to have intrinsic characteristics that make them susceptible to direct exposure to cisplatin. The existing literature suggests, however, that cisplatin might have different patterns of drug trafficking across the blood-labyrinth-barrier, or different degrees of cisplatin uptake to the hair cells in the cochlear and vestibular compartments. This review proposes an explanation for the preferential cochleotoxicity of cisplatin based on current evidence as well as the anatomy and physiology of the inner ear. The endocochlear potential, generated by the stria vascularis, acting as the driving force for hair cell mechanoelectrical transduction might also augment cisplatin entry into cochlear hair cells. Better understanding of the stria vascularis might shed new light on cochleotoxic mechanisms and inform the development of otoprotective interventions to moderate cisplatin associated ototoxicity.

Detecting positional vertigo using an ensemble of 2D convolutional neural networks

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We trained Deep Neural Networks to detect attacks of motion provoked dizziness.

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2D Convolutional Deep Neural Networks outperform 1D network architectures.

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Best results were provided by input features combining eye- and head-movement.

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An ensemble of five networks outperformed each individual network alone.

The aim of the work presented here was to develop a system that can automatically identify attacks of dizziness occurring in patients suffering from positional vertigo, which occurs when sufferers move their head into certain positions. We used our novel medical device, CAVA, to record eye- and head-movement data continually for up to 30 days in patients diagnosed with a disorder called Benign Paroxysmal Positional Vertigo. Building upon our previous work, we describe a novel ensemble of five 2D Convolutional Neural Networks, using composite recognition features, including eye-movement data and three-channel accelerometer data. We achieve an F1 score of 0.63 across an 11-fold cross-fold validation experiment, demonstrating that the system can detect a few seconds of motion provoked dizziness from within over a 100 h of normal eye-movement data. We show that the system outperforms our previous 1D Neural Network approach, and that our ensemble classifier is superior to each of the individual networks it contains. We also demonstrate that our composite recognition features provide improved performance over results obtained using the individual data sources independently.

Clinical effect of vestibular rehabilitation on benign paroxysmal positional vertigo: A protocol for systematic review

BACKGROUND

This study will evaluate the clinical effect of vestibular rehabilitation (VR) on benign paroxysmal positional vertigo (BPPV).

METHODS

In this study, we will identify relevant trials on the topic published in MEDLINE, EBASE, Web of Science, Cochrane Library, Scopus, CINAHL, CBM, and CNKI from inception to the present. We will also search conference proceedings, thesis/dissertation, ongoing trials in clinical trial registry, and reference lists of included studies. Two researchers will independently carry out record selection, data extraction, and study quality assessment, respectively. Any disagreement will be arbitrated and solved with the help of a third researcher. If necessary, we will conduct random-effects meta-analysis to pool the effect estimates of included trials determined to be acceptable heterogeneity.

RESULTS

We will summarize the latest evidence to assess the effect of VR for the treatment of patients with BPPV.

CONCLUSION

The findings of this study will help determine whether or not VR is effective in treating BPPV.

OSF REGISTRATION

osf.io/k83y5.

Comparison of test results from two separate video head impulse test systems in a cohort of patients diagnosed with a unilateral vestibular schwannoma

PURPOSE

Video head impulse testing (vHIT) is a relatively new technology enabling evaluation of vestibular function. The aim of this study was to compare the test results from two separate vHIT systems in a group of patients diagnosed with a unilateral vestibular schwannoma (VS) with regards to sensitivity, specificity and inter-examiner differences.

METHODS

Forty-two patients were examined with two separate vHIT systems: EyeSeeCam^® (system A) and ICS Impulse^® (system B), by one of two examiners. All six semicircular canals (SCCs) were tested under standardized conditions, and strict criteria were set up for post-test interpretation.

RESULTS

With the majority of test parameters, the two test systems were in agreement. Vestibular deficits were found in 40.5% (system A) to 45% (system B) of patients with a VS on the tested side; corresponding to a positive predictive value (PPV) of 86.4% (system B) to 94.4% (system A). The specificity was 97.6% for system A and 92.9% for system B. An overall agreement between the two vHIT systems measured as kappa was computed to be 0.61. There were no significant inter-examiner differences. When testing the vertical SCCs, a tendency of too high mean gain values was seen with system A but not with system B.

CONCLUSION

In patients with unilateral VS, vHIT is a test with moderate sensitivity and high specificity in regard to identification of a vestibular deficit. There were no significant differences in test results between the two vHIT systems.

Cervical spine radiographs in patients with vertigo and dizziness

OBJECTIVE

The purpose of this study is to investigate the role of cervical radiography in the study of patients with vertigo and dizziness.

PATIENTS

This is a retrospective single-institution case series study of 493 patients suffering from vertigo and dizziness who were referred (from January 2011 to December 2012) to the hospital to study those symptoms.

METHODS

We studied cervical radiographies, CT and MRI of the cervical spine made in the sample and the radiological findings. We analyzed demographic characteristics, presence of psychiatric pathology and emergency assistance due to vertigo in patients who have undergone cervical study.

RESULTS

A total of 57% of patients had cervical radiography made; this was more frequent in women, Spanish people, with psychiatric pathology and who have gone to the emergency department for vertigo (p < 0.05). Degenerative changes were found in 74.1% of the patients with radiography made, more frequently at an older age, osteophytes in 49.5% and abnormal cervical lordosis in 37.1%.

CONCLUSIONS

There are sociodemographic factors that influence in the request for cervical radiographs in patients with vertigo and dizziness. Given the suspicion of cervical vertigo, we do not consider that the findings in the radiographs help in the diagnosis. In our opinion, an excessive use of cervical radiography is made in patients with vertigo and dizziness.

Comparing Ocular Responses to Caloric Irrigation and Electrical Vestibular Stimulation in Vestibular Schwannoma

Electrical Vestibular Stimulation (EVS) is a non-invasive technique for activating the vestibular-ocular reflex, evoking mainly a torsional eye movement response. We have previously demonstrated that this response can be used to detect vestibular asymmetry in patients with vestibular schwannoma (VS). Here we perform a direct comparison of EVS with caloric irrigation in this patient group. We studied 30 patients with unilateral VS, alongside an equal number of aged-matched healthy control subjects. EVS current was delivered to the mastoid process in a monaural configuration using a sinusoidal stimulus (2 Hz; ± 2 mA; 10 s), with an electrode placed over the spinous C7 process. Evoked eye movements were recorded from the right eye in darkness using an infra-red sensitive camera while the subject sat relaxed with their head on a chinrest. Ocular torsion was subsequently tracked off-line using iris striations. Each subject separately underwent water caloric irrigation, in accordance with the British Society of Audiology guidelines. For the caloric test, eye movement was recorded in the yaw axis using electro-oculography. For both EVS and calorics, inter-aural response asymmetry was calculated to determine the extent of canal paresis. Both tests revealed impaired vestibular function in the ipsilesional ear of VS patients, with a mean asymmetry ratio of 15 ± 17% and 18 ± 16% for EVS and calorics, respectively. Overall, the caloric test results discriminated controls from patients slightly more effectively than EVS (Cohen's D effect size = 1.44 vs. 1.19). Importantly, there was a significant moderate correlation between the AR values produced by EVS and calorics (r = 0.53, p < 0.01), and no significant difference between mean AR estimates. When questioned, ≥85% of participants subjectively preferred the EVS experience, in terms of comfort. Moreover, it took ~15 min to complete, vs. ~1 h for caloric. These results confirm that the results of the EVS test broadly agree with those of caloric irrigation, in terms of detecting vestibular asymmetry. Furthermore, they suggest a higher degree of convenience and patient comfort.

Comparison of acute vertigo diagnosis and treatment practices between otolaryngologists and non-otolaryngologists: A multicenter scenario-based survey

Acute vertigo is a common problem in emergency departments. However, clinical strategies of acute vertigo care vary among care providers. The aim of the study was to investigate differences in diagnosis [Dix-Hallpike test, the head impulse, nystagmus, and the test of skew (HINTS) procedure, and imaging modalities] and treatment (pharmacological treatments and the Epley maneuver) by otolaryngologists and non-otolaryngologists in emergency medicine settings. We used a multicenter case-based survey for the study. Four clinical vignettes of acute vertigo (posterior canal benign paroxysmal positional vertigo, vestibular neuritis, Meniere disease, and nonspecific vertigo) were used. Total 151 physicians from all study sites participated in the study. There were 84 non-otolaryngologists (48 emergency physicians and 36 internists) and 67 otolaryngologists. The multivariate analysis indicated that otolaryngologists ordered fewer CT scans (odds ratio (OR), 0.20; 95% confidence interval (CI), 0.07-0.53) and performed fewer HINTS procedures (OR, 0.17; 95% CI, 0.06-0.46), but used the Dix-Hallpike method more often (OR, 2.36; 95% CI, 1.01-5.52) for diagnosis compared to non-otolaryngologists. For treatment, otolaryngologists were less likely to use the Epley method (OR, 0.19; 95% CI, 0.07-0.53) and metoclopramide (OR, 0.09; 95% CI, 0.01-0.97) and more likely to use sodium bicarbonate (OR, 20.50; 95% CI, 6.85-61.40) compared to non-otolaryngologists. We found significant differences in the acute vertigo care provided by non-otolaryngologists and otolaryngologists from a vignette-based research. To improve acute vertigo care, educational systems focusing on acute vertigo are needed.

Visual dependency and postural control on swing performance in golf players

Individuals have to reweight the respective contribution of the different sources of sensorial information for regulating posture and balance, especially during fine task execution. Given the evidences indicating strategy during swing performance as associated with prioritization of task-relevant visuospatial information for skill execution, the aim of the present work is to assess differences in visual dependency (VD) and postural control in a population of expert (EXP) and non-expert (NEXP) golfers when compared with healthy subjects (HC) and to discover possible relationships between these outcomes and swing performance. Thus, 15 golfers (EXP = 7; NEXP = 8) and 32 matched HC underwent otoneurological testing including video Head Impulse Test, posturography and Rod and Disk Test (RDT). Golf players also underwent a swing session procedure, which performance was measured by means of the Flightscope X2 Doppler-radar launch monitor system. EXP subjects demonstrated significant (p < 0.05) lower values in i) counter-clockwise (CCW) and clockwise (CW) dynamic conditions when compared with both NEXP and HC subjects RDT outcome measures and ii) surface and length posturography values as compared with HC subjects. When treating golf players outcomes as 'a continuum', CCW and CW scores were found to positively correlate with both lateral distance and horizontal launch angle and to negatively correlate with spin rpm. In conclusion, the present study suggests that the high-level of visual-independency demonstrated by EXP subjects may be functionally related in expert golfers to an effective motor strategy preferentially not referring to an inappropriate reliance on visual input.