Machine Learning Models for Predicting Facial Nerve Palsy in Parotid Gland Surgery for Benign Tumors.

BACKGROUND: Despite the increasing use of intraoperative facial nerve monitoring during parotid gland surgery (PGS) and the improvement in the preoperative radiological assessment, facial nerve injury (FNI) remains the most severe complication after PGS. Until now, no studies have been published regarding the application of machine learning (ML) for predicting FNI after PGS. We hypothesize that ML would improve the prediction of patients at risk. METHODS: Patients who underwent PGS for benign tumors between June 2010 and June 2019 were included. RESULTS: Regarding prediction accuracy and performance of each ML algorithm, the K-nearest neighbor and the random forest achieved the highest sensitivity, specificity, positive predictive value, negative predictive value F-score, receiver operating characteristic (ROC)-area under the ROC curve, and accuracy globally. The K-nearest neighbor algorithm achieved performance values above 0.9 for specificity, negative predictive value, F-score and ROC-area under the ROC curve, and the highest sensitivity and positive predictive value. CONCLUSIONS: This study demonstrates that ML prediction models can provide evidence-based predictions about the risk of FNI to otolaryngologists and patients. It is hoped that such algorithms, which use clinical, radiological, histological, and cytological information, can improve the information given to patients before surgery so that they can be better informed of any potential complications.

Sialendoscopy-assisted transoral approach for parotid gland lithiasis.

INTRODUCTION: Although lithiasis represents more than 60% of all cases of salivary gland obstruction, only 20% occurs in the Stensen´s duct. Nonetheless, the potential complications related to parotid gland surgery due to facial nerve injury, makes the development of minimally invasive techniques highly relevant. MATERIALS AND METHODS: A pilot study was conducted to assess results of patients treated by sialendoscopy-assisted trans-oral approach to treat Stensen´s duct lithiasis. RESULTS: Eight patients were included; all of them operated satisfactorily. Six of them were male, and 2 were female. The mean size of the stones was 9.6 mm (Min: 6 mm/Max: 16 mm). Regarding to lithiasis location: it was anterior to the masseter line in the distal third of the Stensen's duct in seven patients and in another patient was immediately below the buccinator muscle. During the follow-up, all patients presented a healthy functioning of the gland after the compressive massage. Regarding complications, one patient presented a Stensen's duct stenosis, which required reintervention. CONCLUSION: The transoral Stensen´s duct approach represents a safe technique for lithiasis bigger than 3 mm in the distal portion of the Stensen´s duct, anterior to the Masseter Muscle line and when other minimal invasive techniques fail.

Complications after Functional Neck Dissection in Head and Neck Cancer Patients: An Observational, Retrospective, Single-Centre Study.

INTRODUCTION: Functional neck dissection (FND) represents a surgical procedure usually associated with less morbidity. METHODS: An observational, retrospective, analysis of patients diagnosed with any type of head and neck malignancy was designed to summarize and report the incidence of postoperative complications in patients undergoing FND including just those levels described for selective neck dissections in a tertiary university hospital between June 2016 and June 2019. RESULTS: 131 patients met the inclusion criteria. The total number of sides studied was 200. 40.5% of the patients suffer a complication in the postoperative period, being the spinal accessory nerve (SAN) injury the most common complication (10%). We did not find any statistical -correlation between the previous organ-preservation treatments and surgical complications (p = 0.207). An advanced T stage (p = 0.009) and the need of bilateral FND (p = 0.034) were significantly correlated with a higher risk of surgical complications. CONCLUSION: FND represents a useful technique. In this study, 40.5% of the patients suffer a complication in the postoperative period, being the SAN injury the most common complication. However, these data contribute to increasing our knowledge about surgical complications related to FND.

Wireless inertial measurement unit (IMU)-based posturography.

BACKGROUND: Classical posturography techniques have been recently enhanced by the use of different motion tracking devices, but for technical reasons they are not used to track directly the body spatial position of a subject. OBJECTIVE: To describe and clinically evaluate a wireless inertial measurement unit-based mobile system to track body position changes. METHODS: The developed system used a calculus transformation method using the acceleration data corrected by Kalman and Butterworth filters to output position data. A prospective non-randomized clinical study involving 15 healthy subjects was performed to evaluate the agreement between the confidence ellipse areas synchronously measured by the new developed system and a classical posturography system while performing a modified clinical test of sensory interaction in balance. RESULTS: The overall intra-class correlation index was 0.93 (CI 0.89, 0.96). Grouped by conditions, under conditions 1-4, Pearson's correlation was 0.604, 0.78, 0.882, and 0.81, respectively. CONCLUSION: The developed wireless inertial measurement unit-based posturography system was valid for tracking the sway variances in normal subjects under habitual clinical testing conditions. Further studies are needed to validate this system on patients and also under other posture conditions.

Metformin Results in Diametrically Opposed Effects by Targeting Non-Stem Cancer Cells but Protecting Cancer Stem Cells in Head and Neck Squamous Cell Carcinoma.

Cancer stem cells (CSCs) have been shown as a distinct population of cancer cells strongly implicated with resistance to conventional chemotherapy. Metformin, the most widely prescribed drug for diabetes, was reported to target cancer stem cells in various cancers. In this study, we sought to determine the effects of metformin on head and neck squamous cell carcinoma (HNSCC). CSCs and non-stem HNSCC cells were treated with metformin and cisplatin alone, and in combination, and cell proliferation levels were measured through MTS assays. Next, potential targets of metformin were explored through computational small molecule binding analysis. In contrast to the reported effects of metformin on CSCs in other cancers, our data suggests that metformin protects HNSCC CSCs against cisplatin in vitro. Treatment with metformin resulted in a dose-dependent induction of the stem cell genes CD44, BMI-1, OCT-4, and NANOG. On the other hand, we observed that metformin successfully decreased the proliferation of non-stem HNSCC cells. Computational drug⁻protein interaction analysis revealed mitochondrial complex III to be a likely target of metformin. Based on our results, we present the novel hypothesis that metformin targets complex III to reduce reactive oxygen species (ROS) levels, leading to the differential effects observed on non-stem cancer cells and CSCs.

Porcine experimental model for perforator flap raising in reconstructive microsurgery.

BACKGROUND: Perforator free flap-based reconstruction of the head and neck is a challenging surgical procedure and needs a steep learning curve. A reproducible mammal large animal model with similarities to human anatomy is relevant for perforator flap raising and microanastomosis. The aim of this study was to assess the feasibility of a swine model for perforator-based free flaps in reconstructive microsurgery. METHODS: Eleven procedures were performed under general anesthesia in a porcine model, elevating a skin flap vascularized by perforating musculocutaneous branches of the superior epigastric artery to evaluate the relevance of this model for head and neck reconstructive microsurgery. RESULTS: The anterior abdominal skin perforator-based free flap in a swine model irrigated by the superior epigastric artery was elevated in eleven procedures. In six of these procedures, we could perform an arterial and venous microanastomosis to the great vessels located in the base of the neck. CONCLUSIONS: The porcine experimental model of superior epigastric artery perforator-based free flap reconstruction offers relevant similarities to the human deep inferior epigastric artery perforator flap. We could demonstrate this model as acceptable for perforator free flap training due to the necessity of perforator and pedicle dissection and transfer to a distant area.

Cochlear implantation in the elderly: outcomes, long-term evolution, and predictive factors.

OBJECTIVE: Our goal in this study is to find out the outcomes of cochlear implantation in elderly (> 60 years) and check if this improvement is similar to that of their younger counterparts in short- and long-term evolution. In addition, we have attempted to ascertain the predictive factors that might affect the verbal comprehension results of older patients. STUDY DESIGN: Retrospective cohort study. METHODS: Ninety-four patients older than 40 years, divided into two groups. 40-60 years n = 55 and > 60 years n = 39. A pure-tone audiometry, a disyllabic word test, and the test of phonetically balanced sentences of Navarra were made in silence to each patient. These measurements were made pre-implantation and 1, 5, and 10 year post-implantation. Peri- and postoperative complications were registered. The hypothetic predictive factors of post-implanted performance were evaluated in the elderly. RESULTS: Our study shows no significant difference between young and old adult´s outcomes in short- and long-term evolutions, nor in the complication rate. Furthermore, we proved the significant influence of the side of implantation, use of hearing aids, and duration of hearing loss in the short- and long-term results in the elderly. CONCLUSION: This study shows that cochlear implantation in the elderly is as safe, useful, and worthwhile as in young adults. Age has a low influence in cochlear implant outcomes; however, we have found the significant influence of the side of implantation, the use of hearing aids, and the duration of hearing loss in the short- and long-term results.

Utility of diffusion-weighted magnetic resonance imaging in the diagnosis of cholesteatoma and the influence of the learning curve.

OBJECTIVE: The aim of this study is to assess the usefulness and reliability of this technique in our center, correlating the radiological and surgical findings and to study the influence of the learning curve by comparing the initial results with a radiological analysis performed 3 years after. STUDY DESIGN: Retrospective cohort study. METHODS: 67 patients with clinical cholesteatoma suspicion were included in the study, 24 with previously not operated cholesteatoma and 43 with suspicion of recurrent or residual cholesteatoma. All of them underwent diffusion-weighted magnetic resonance imaging, comparing these results with the histological confirmation after surgery. At 3 years, a blind radiological review of these cases was performed and the results were compared with those obtained after the first assessment to objectify the influence of the learning curve. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of the total sample were 93.9, 77.8, 92 and 82.4. The overall results after the blind review of the cases were 95.9, 94.4, 97.9 and 89.5, respectively. CONCLUSION: The diffusion-weighted magnetic resonance imaging is a very useful technique during the diagnostic process of doubtful cases of cholesteatoma, especially in cases of follow-up. As for the influence of the learning curve, we observed a clear improvement in the specificity of the test.

The role of subtotal petrosectomy in cochlear implant recipients.

Describe the indications and outcome of subtotal petrosectomy for cochlear implant recipients. Tertiary care referral center. This is a retrospective study of all subtotal petrosectomies and cochlear implants performed between January 2012 and December 2014. We review the charts of these patients collecting the following data: age, gender, otologic history, audiologic tests, indication of subtotal petrosectomy, data of surgery, surgical and immediate complications, late complications and follow-up of for at least 2.5 years. 12 cases of subtotal petrosectomies with cochlear implantation in 11 patients were performed during this period; 2 children and 10 adults. The indication for a cochlear implant was in 10 cases bilateral severe to profound sensorineural hearing loss and in the remaining 2 cases was asymmetric hearing loss or unilateral hearing loss. The reason for performing a subtotal petrosectomy was chronic otitis media with or without cholesteatoma, radical cavities from previous surgeries or electrode extrusion of previously implanted devices. All cases were performed in one stage. One patient had an infectious complication that required revision surgery and finally an explantation. No other complications are described. Subtotal petrosectomy combined with cochlear implantation is a procedure required in certain situations. It is an effective and safe procedure for managing middle ear problems and creating a safe cavity to receive a cochlear implant either in adults and children.

[Treatment of giant acoustic neuromas]. / Tratamiento del neurinoma acústico gigante.

INTRODUCTION AND OBJECTIVES: To analyze the treatment modality and outcome of a series of patients with giant acoustic neuromas, a particular type of tumour characterised by their size (extracanalicular diameter of 4cm or more) and high morbidity and mortality. MATERIALS AND METHODS: This was a retrospective unicentre study of patients with acoustic neuromas treated in a period of 12 years. In our institutional series of 108 acoustic neuromas operated on during that period, we found 13 (12%) cases of giant acoustic neuromas. We reviewed the available data of these cases, including presentation and several clinical, anatomical, and microsurgical aspects. RESULTS: All patients were operated on by the same neurosurgeon and senior author (EU) using the suboccipital retrosigmoid approach and complete microsurgical removal was achieved in 10 cases. In one case, near total removal was deliberately performed, in another case a CSF shunt was placed as the sole treatment measure, and in the remaining case no direct treatment was given. One patient died in the immediate postoperative period. One year after surgery, 4 patients showed facial nerve function of iii or more in the House-Brackman scale. CONCLUSIONS: The 4 most important prognostic characteristics of giant acoustic neuromas are size, adhesion to surrounding structures, consistency and vascularity. Only the first of these is evident in neuroimaging. Giant acoustic neuromas are characterised by high morbidity at presentation as well as after treatment. Nevertheless, the objective of complete microsurgical removal with preservation of cranial nerve function is attainable in some cases through the suboccipital retrosigmoid approach.

Clinical practice guideline on the management of vestibular schwannoma.

INTRODUCTION: Vestibular schwannoma (VS) is the most common tumour of the cerebellopontine angle. The greater accessibility to radiological tests has increased its diagnosis. Taking into account the characteristics of the tumour, the symptoms and the age of the patient, three therapeutic strategies have been proposed: observation, surgery or radiotherapy. Choosing the most appropriate for each patient is a frequent source of controversy. MATERIAL AND METHODS: This paper includes an exhaustive literature review of issues related to VS that can serve as a clinical guide in the management of patients with these lesions. The presentation has been oriented in the form of questions that the clinician usually asks himself and the answers have been written and/or reviewed by a panel of national and international experts consulted by the Otology Commission of the SEORL-CCC. RESULTS: A list has been compiled containing the 13 most controversial thematic blocks on the management of VS in the form of 50 questions, and answers to all of them have been sought through a systematic literature review (articles published on PubMed and Cochrane Library between 1992 and 2023 related to each thematic area). Thirty-three experts, led by the Otology Committee of SEORL-CCC, have analyzed and discussed all the answers. In Annex 1, 14 additional questions divided into 4 thematic areas can be found. CONCLUSIONS: This clinical practice guideline on the management of VS offers agreed answers to the most common questions that are asked about this tumour. The absence of sufficient prospective studies means that the levels of evidence on the subject are generally medium or low. This fact increases the interest of this type of clinical practice guidelines prepared by experts.

A New Method for Gain Calculation in Quantified Visuo-vestibular Interaction Test.

OBJECTIVE: To develop a new method to quantify visually-enhanced vestibulo-ocular reflex (VVOR) gain, in patients with vestibular function loss, that is mathematically suitable given the nature of the test, and determine the reliability of the method by comparing results with those of the gold standard, the video head impulse test (vHIT). MATERIALS AND METHODS: We developed a new method for VVOR gain quantification and conducted a cross-sectional study in patients diagnosed with vestibular function loss and controls, all participants undergoing both a VVOR test and a vHIT. We measured VVOR gain with three different methods: area under the curve (AUC), slope regression, and a Fourier method (VVORAUC , VVORSP , and VVORFR , respectively); and compared these gain values with vHIT gain calculated using the AUC method. RESULTS: Overall, 111 patients were included: 29 healthy subjects and 82 patients with vestibular function loss. Intraclass correlation coefficients (ICC(1,1)) between gain from the gold standard and each of the VVOR gain methods were: 0.68 (CI: 0.61-0.75) for VVORAUC , 0.66 (CI: 0.58-0.73) for VVORSP and 0.71 (CI: 0.64-0.77) for VVORFR . No interference was found between VVOR gain calculation methods and potentially influential variables considered (p ≥ 0.98). CONCLUSION: The new method for quantifying VVOR gain showed good concordance with the vHIT method. LEVEL OF EVIDENCE: 2: Individual cross-sectional studies with consistently applied reference standard and blinding (Diagnosis) Laryngoscope, 133:3554-3563, 2023.

Translation into Spanish and validation of the Tinnitus Functional Index (TFI).

OBJECTIVE: The objectives of this study were to translate into Spanish, cross-culturally adapt and validate the TFI. MATERIALS AND METHODS: The TFI questionnaire translated into Spanish (Sp-TFI) and cross-culturally adapted following the published guidelines on cross-cultural adaptation of health questionnaires was evaluated using two indicators. Its internal consistency was assessed with Cronbach's α considering the Tinnitus Handicap Inventory (THI) as the gold standard. Further, its test-retest reliability was assessed with intraclass correlation coefficients (ICCs). ICCs were also calculated for the THI and visual analogue scales (VAS) for tinnitus tested and retested in all participants. RESULTS: The mean age of the 18 participants was 45.77 (SD: 11.87) years; 12 were female (66.67 %) and 6 were male (33.33%). Half of the participants experienced tinnitus in their left ear and half in their right. The mean pure-tone average (PTA) in the affected ear was 29.34 (SD: 8.08) dB-HL. Regarding internal consistency and reliability of the Sp-TFI respectively, Cronbach's α was 0.83 and the ICC type (2,1) was 1 (CI: 0.99-1). Among the variables studied, we found the following independent predictors had statistically significant effects on THI score: sex (p < 0.01), PTA (p = 0.03), overall Sp-TFI score (p = 0.02) and Sp-TFI SL, R and A subscale scores (p = 0.03, p = 0.03, and p < 0.01, respectively). CONCLUSION: Based on the internal consistency and reliability results obtained in this study, the cross-culturally adapted Spanish version of the TFI (Sp-TFI) has been validated for use in Spain. LEVEL OF EVIDENCE: 2B: Individual cohort study/low-quality randomized control studies.

Salinomycin induces cell death and differentiation in head and neck squamous cell carcinoma stem cells despite activation of epithelial-mesenchymal transition and Akt.

BACKGROUND: Cancer stem cells (CSC) are believed to play a crucial role in cancer recurrence due to their resistance to conventional chemotherapy and capacity for self-renewal. Recent studies have reported that salinomycin, a livestock antibiotic, selectively targets breast cancer stem cells 100-fold more effectively than paclitaxel. In our study we sought to determine the effects of salinomycin on head and neck squamous cell carcinoma (HNSCC) stem cells. METHODS: MTS and TUNEL assays were used to study cell proliferation and apoptosis as a function of salinomycin exposure in JLO-1, a putative HNSCC stem cell culture. MTS and trypan blue dye exclusion assays were performed to investigate potential drug interactions between salinomycin and cisplatin or paclitaxel. Stem cell-like phenotype was measured by mRNA expression of stem cell markers, sphere-forming capacity, and matrigel invasion assays. Immunoblotting was also used to determine expression of epithelial-mesenchymal transition (EMT) markers and Akt phosphorylation. Arrays by Illumina, Inc. were used to profile microRNA expression as a function of salinomycin dose. RESULTS: In putative HNSCC stem cells, salinomycin was found to significantly inhibit cell viability, induce a 71.5% increase in levels of apoptosis, elevate the Bax/Bcl-2 ratio, and work synergistically with cisplatin and paclitaxel in inducing cell death. It was observed that salinomycin significantly inhibited sphere forming-capability and repressed the expression of CD44 and BMI-1 by 3.2-fold and 6.2-fold, respectively. Furthermore, salinomycin reduced invasion of HNSCC stem cells by 2.1 fold. Contrary to expectations, salinomycin induced the expression of EMT markers Snail, vimentin, and Zeb-1, decreased expression of E-cadherin, and also induced phosphorylation of Akt and its downstream targets GSK3-ß and mTOR. CONCLUSIONS: These results demonstrate that in HNSCC cancer stem cells, salinomycin can cause cell death and decrease stem cell properties despite activation of both EMT and Akt.

Island cartilage tympanoplasty in revision cases: anatomic and functional results.

We report our experience with island cartilage tympanoplasty in revision cases and assess the anatomical and functional outcomes. We conducted a retrospective chart review at a tertiary referral center for patients who underwent revision tympanoplasty using cartilage with the island technique without mastoidectomy between January 2002 and December 2008. 60 cases were included in the study and successful closure without reperforation was obtained in 52 of 60 patients (87%). Three failed cases underwent a subsequent procedure endaurally with a positive result (92% accumulated success rate). Average postoperative pure-tone audiometry air-bone gap was 13 ± 7 dB compared with 21 ± 11 dB preoperatively (p = 0.004). An overall postoperative air-bone gap of 20 dB or less was achieved in 46 of the 60 patients (76.7%). Tympanoplasty with island cartilage grafting is a reliable procedure for revision cases with excellent anatomic results as well as significant improvement of hearing.

Synchronized refixation saccades in enhanced VVOR test. A new application for PR score.

OBJECTIVE: Main objectives for this study were to develop a quantification method to obtain a Perez-Rey (PR) score adapted to the VVOR test and to evaluate the correlation of the PR score obtained with quantified VVOR with the PR score of the vHIT test. METHODS: A new PR score calculation method for quantified VVOR test was developed using the MATLAB computational software based on saccadic response time latency variability between each head oscillation cycle of the VVOR test. Retrospective correlation between PR scores in VVOR and vHIT tests, performed in the same vHIT testing session for patients with vestibular neuritis and vestibular neurectomy, was performed to correlate new PR (VVOR) score with the classic PR (vHIT) score. RESULTS: Thirty patients were included: 11 post-neurectomy and 19 subacute vestibular neuritis. Pearson's correlation coefficient (R2) for the overall sample was 0.92 (p < 0.001) and 95% confidence interval was 0.85 -0.96. In the linear mixed-effects statistical model developed, only PRVHIT and PRVVOR scores showed statistical association in Wald X2 test (p = 0.008). CONCLUSION: The new developed PR score for synchronization measurement of saccadic responses in VVOR testing is a valid method that outputs synchronization values and highly correlates with PR score in vHIT test.

"Omepralith": A novel simulation model for training in sialoendoscopy.

INTRODUCTION: There are no previously described training models for learning or teaching how to remove lithiasis from the salivary ducts. Therefore, we present a new simulation model to enable us to faithfully represent the process of endoscopic lithiasis extraction by sialoendoscopy. MATERIALS AND METHODS: A simulation model was developed using a pig's head, omeprazole spheres were used to simulate lithiasis in the various ducts of each salivary gland and a Dormia basket was used to train in extraction of the lithiasis model. RESULTS: Twenty-seven residents in training and/or young specialists were successfully trained in this technique using this model. Twenty-six (96.3%) considered the model useful for training in the use of baskets; all of them were able to capture the omeprazole sphere in the salivary duct. A satisfaction rate of 92.25 out of 100 points was obtained through an anonymous survey. CONCLUSION: We describe a novel simulation model using omeprazole spheres, which allows the surgeon to practice how to diagnose and treat obstructive pathology of the salivary glands in a risk-free environment guaranteeing the reproducibility of the technique in conditions similar to those of normal practice.

Unplanned Hospital Readmission and Visit to the Emergency Room in the First Thirty Days after Head and Neck Surgery: A Prospective, Single-center Study.

Introduction Head and neck surgery remains a complex field; the patients can suffer important functional or life-threating complications after treatment that need unplanned readmissions, increasing the cost related to the treatment. Objective To evaluate the incidence risk factors and causes associated with 30-day unplanned hospital readmission and visit to the emergency room (ER) after surgery for head and neck cancer. Methods Prospective, longitudinal, nonrandomized study. Results A total of 834 patients were included, 726 in the major surgery group and 108 in the minor surgery group. The 30-day readmission rate for all causes was of 7,9% for the patients treated by a major surgery and of 0% for the patients treated in the outpatient clinic for minor procedures, to a total readmission rate of 6,8%. The rate of visit to the emergency room for all causes in the first 30 days was of 14% for the patients treated by a major surgery and of 2,7% for the patients treated in the outpatient clinic. Conclusion Major surgery, the American Society of Anesthesiologists (ASA) status and type of wound are conditions related to unplanned readmission or visit to the ER in the first 30 day after discharge. The most commonly associated causes are infections or wound complications. An evidence-based risk stratification of the patients can be important to improve decision-making and resource utilization. An educational strategy can provide possible ways to improve the rate of readmission and reduce the amount of money expended by healthcare systems.

Enhanced Eye Velocity With Backup Saccades in vHIT Tests of a Menière Disease Patient: A Case Report.

Reduced eye velocity and overt or covert compensatory saccades during horizontal head impulse testing are the signs of reduced vestibular function. However, here we report the unusual case of a patient who had enhanced eye velocity during horizontal head impulses followed by a corrective saccade. We term this saccade a "backup saccade" because it acts to compensate for the gaze position error caused by the enhanced velocity (and enhanced VOR gain) and acts to return gaze directly to the fixation target as shown by eye position records. We distinguish backup saccades from overt or covert compensatory saccades or the anticompensatory quick eye movement (ACQEM) of Heuberger et al. (1) ACQEMs are anticompensatory in that they are in the same direction as head velocity and so, act to take gaze off the target and thus require later compensatory (overt) saccades to return gaze to the target. Neither of these responses were found in this patient. The patient here was diagnosed with unilateral definite Meniere's disease (MD) on the right and had enhanced VOR (gain of 1.17) for rightward head impulses followed by backup saccades. For leftwards head impulses eye velocity and VOR gain were in the normal range (VOR gain of 0.89). As further confirmation, testing with 1.84 Hz horizontal sinusoidal head movements in the visual-vestibular (VVOR) paradigm also showed these backup saccades for rightwards head turns but normal slow phase eye velocity responses without backup saccades for leftwards had turns. This evidence shows that backup saccades can be observed in some MD patients who show enhanced eye velocity responses during vHIT and that these backup saccades act to correct for gaze position error caused by the enhanced eye velocity during the head impulse and so have a compensatory effect on gaze stabilization.

Clinical Prevalence of Enhanced Vestibulo-Ocular Reflex Responses on Video Head Impulse Test.

OBJECTIVE: To measure and analyze the clinical and epidemiological characteristics of patients and healthy controls with enhanced eye velocity responses as well as evaluate their relationship with endolymphatic hydrops related diseases. STUDY DESIGN: Cross-sectional clinical study. SETTING: Tertiary hospital. PARTICIPANTS: Three hundred sixty three participants allocated to patients (310) and healthy control (53) groups were collected on first time visit to neurotology unit. INTERVENTION: Diagnostic. MAIN OUTCOME MEASURES: Video head impulse test records, clinical diagnose, and variables and demographic data were used to get cross tables, a general linear model, diagnostic epidemiological parameters, and machine learning variable importance evaluation methods. RESULTS: All the statistical tests revealed a significant association between enhanced vestibulo-ocular reflex (VOR) and diagnostic categories (p < 0.001). Chi-squared residual and machine learning analyses showed Menière's disease as the main associated diagnostic category, whereas the lowest residuals and gain values were found in the control group. Enhanced VOR as a diagnostic sign of Menière's disease had a sensitivity of 42.59% and a specificity of 86.32%, with an odds ratio of 4.68 (p < 0.001). CONCLUSION: There is a significantly higher prevalence of enhanced VOR responses in patients with Menière's disease, central origin vertigo, otosclerosis, and vestibular migraine than in those with other neurotologic diseases and controls. Our study found that enhanced VOR are not pathognomonic of hydrops-related diseases and the diagnosis should not solely be based on these and instead take into context other clinical and examination findings.