The developed software (HITCal) may be a useful tool in the analysis and measurement of the saccadic video head impulse test (vHIT) responses and with the experience obtained during its use the authors suggest that HITCal is an excellent method for enhanced exploration of vHIT outputs. To develop a (software) method to analyze and explore the vHIT responses, mainly saccades. HITCal was written using a computational development program; the function to access a vHIT file was programmed; extended head impulse exploration and measurement tools were created and an automated saccade analysis was developed using an experimental algorithm. For pre-release HITCal laboratory tests, a database of head impulse tests (HITs) was created with the data collected retrospectively in three reference centers. This HITs database was evaluated by humans and was also computed with HITCal. The authors have successfully built HITCal and it has been released as open source software; the developed software was fully operative and all the proposed characteristics were incorporated in the released version. The automated saccades algorithm implemented in HITCal has good concordance with the assessment by human observers (Cohen's kappa coefficient = 0.7).

Objective. To evaluate vestibular compensation via measurement of the vestibulo-ocular reflex (VOR) following vestibular schwannoma surgery, and its relationship with changes in saccades strategy after surgery. Patients. 36 consecutive patients with vestibular schwannomas, without midbrain compression, who underwent surgical resection. Patients were recruited from University Hospital of Salamanca, Spain. Methods. We assessed the age, sex, tumour size, degree of canalicular weakness and pre-operative video head impulse test (Gain and saccade organization measured with PR score). Gain and saccade organization were compared with post –operative values at discharge and also at 1, 3 and 6 months. PR scores are a measure of the scatter of refixation saccades. Results: Patients with normal pre-operative caloric function had higher PR scores (saccades were scattered) following surgery compared to patients with significant pre-operative canal paresis (P0.05), but a group of patients with very low VOR gain (<0.45) and covert/overt saccades before surgery had lower PR scores after surgery. The differences after six months were not significant. Conclusions: Patients with more severe vestibular dysfunction before vestibular schwannoma surgery show significantly faster vestibular compensation following surgery, manifested by changes in VOR gain and PR score. The scatter of compensatory saccades (as measured by the PR score) may be a surrogate early marker of clinical recovery, given its relationship to the Dizziness Handicap Inventory.

The application described in this study appears to be accurate and valid, thus allowing calculation of a hearing handicap and assessment of the pure-tone air conduction threshold with iPhone/iPad devices. To develop and evaluate a newly developed professional, computer-based hearing handicap calculator and a manual hearing sensitivity assessment test for the iPhone and iPad (AudCal). Multi-center prospective non-randomized validation study. One hundred and ten consecutive adult participants underwent two hearing evaluations, a standard audiometry and a pure-tone air conduction test using AudCal with an iOS device. The hearing handicap calculation accuracy was evaluated comparing AudCal vs a web-based calculator. Hearing loss was found in 83 and 84 out of 220 standard audiometries and AudCal hearing tests (Cohen's Kappa = 0.89). The mean difference between AudCal and standard audiogram thresholds was -0.21 ± 6.38 dB HL. Excellent reliability and concordance between standard audiometry and the application's hearing loss assessment test were obtained (Cronbach's alpha = 0.96; intra-class correlation coefficient = 0.93). AudCal vs a web-based calculator were perfectly correlated (Pearson's r = 1).

Conclusion: VOR adaptation and organization of refixation saccades in a gathered pattern is a process that can be artificially induced in patients with unilateral vestibular loss who have not developed it naturally, improving imbalance and vestibular disability. Objective: To test that temporary grouping of refixation saccades should be linked to better clinical status without gain recovery. Methods: A training to induce the refixation saccades into gathered fashion is performed. The outcome measures are handicap level measured by the dizziness handicap index (DHI) and refixation saccades organization pattern measured by a numeric score called ‘PR’ given by a software developed by the authors. Analysis is done before the training and 1 and 3 months after ending, Non-parametric tests were used for statistical analysis. Results: This study has included 10 healthy subjects (four males, six females), and 16 patients with chronic unsteadiness due to unilateral vestibular loss (nine vestibular neuritis, four post-surgical vestibular schwannoma, and three cases after intra-tympanic gentamycin in patients with Ménière’s disease). The reduction in the DHI score was significant at 1 (p = 0.028) and 3 months (p = 0.042) post-treatment. Also, statistically significant differences were found between the PR score before and PR score 1 (p = 0.005) and 3 months after the treatment (p = 0.003).

Background: Visually enhanced vestibulo–ocular reflex (VVOR) is a well-known bedside clinical test to evaluate visuo–vestibular interaction, with clinical applications in patients with neurological and vestibular dysfunctions. Owing to recently developed diagnostic technologies, the possibility to perform an easy and objective measurement of the VVOR has increased, but there is a lack of computational methods designed to obtain an objective VVOR measurement. Objectives: To develop a method for the assessment of the VVOR to obtain a gain value that compares head and eye velocities and to test this method in patients and healthy subjects. Methods: Two computational methods were developed to measure the VVOR test responses: the first method was based on the area under curve of head and eye velocity plots and the second method was based on the slope of the linear regression obtained for head and eye velocity data. VVOR gain and vestibulo–ocular reflex (VOR) gain were analyzed with the data obtained from 35 subjects divided into four groups: healthy (N = 10), unilateral vestibular with vestibular neurectomy (N = 8), bilateral vestibulopathy (N = 12), and cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) (N = 5). Results: Intra-class correlation index for the two developed VVOR analysis methods was 0.99. Statistical differences were obtained by analysis of variance statistical method, comparing the healthy group (VVOR mean gain of 1 ± 0) with all other groups. The CANVAS group exhibited (VVOR mean gain of 0.4 ± 0.1) differences when compared to all other groups. VVOR mean gain for the vestibular bilateral group was 0.8 ± 0.1. VVOR mean gain in the unilateral group was 0.6 ± 0.1, with a Pearson’s correlation of 0.52 obtained when VVOR gain was compared to the VOR gain of the operated side. Conclusion: Two computational methods to measure the gain of VVOR were successfully developed. The VVOR gain values appear to objectively characterize the VVOR alteration observed in CANVAS patients, and also distinguish between healthy subjects and patients with some vestibular disorders.