The COVID-19 frontiers - sink or swim.

OBJECTIVES: The objective of this study is to address issues faced by doctors working in the COVID-19 units during the second phase of COVID-19 in the Czech Republic, when the country registered the highest per capita rate of new COVID-19 cases in the world. METHODS: A prospective study was designed using Google online questionnaire. Inclusion criteria were doctors from medical and surgical specialties working in COVID-19 units. The Czech Medical Association was approached in obtaining permission and helping us distribute the questionnaire with an introductory message with the aims of the study via email to the chairpersons of 18 medical and surgical Czech Societies and their respective members. The online questionnaire link was active for 31 days. Completion of a questionnaire implied consent to participate. Data was collected from the completed responses and statistical analysis was done. RESULTS: Fifteen out of eighteen invited Societies participated in the study. Out of all the transferred or volunteering doctors at the COVID units, 47.6% were from 9 medical specialties and 52.4% from 6 surgical units. The highest transfers were seen amongst male surgeons with 21 to 35 years of work experience, whilst the youngest group of doctors made the highest contribution. There was no statistical significance between the effects of COVID-19 and gender. Despite adequate medical provisions, 42% of all doctors had issues with procedural diagnostic methods, 40% tested positive for COVID-19 and 31% reported staff reduction leading to diminished patients' admissions and compromised care. Doctors from surgical departments experienced more difficulties in working in COVID-19 units. Furthermore, on contraction of COVID-19, 114 doctors asserted a lack of support and another 26% were unaware of any services. CONCLUSIONS: Our survey reiterates the relationship between factors related to occupational health and safety, standards of patient care and possibility of medicolegal consequences with the continuing COVID-19 pandemic.

Hemihypoglossal-facial nerve anastomosis: results and electromyographic characterization.

INTRODUCTION: The facial nerve surgery belongs to the basic procedures during lateral skull base approaches. Its damage has serious medical and psychological consequences, and therefore mastery of reconstruction and correction techniques should belong to the repertoire of skull base surgeons. The goal of this study was to demonstrate usefulness of electromyographic follow-up in facial nerve reconstruction. MATERIAL AND METHODS: A total of 16 patients underwent hemihypoglossal-facial anastomosis between 2005 and 2017. Most of the primary lesions came from vestibular schwannoma surgery. All patients were examined with electromyography and scored according to the House-Brackmann and IOWA grading scales. Function of the tongue has been evaluated. RESULTS: Ten patients achieved definitive House-Brackmann grade 3 score (62.5%). We did not observe any association with the patient's age, previous irradiation and the etiology of the damage. Electromyography showed pathological spontaneous activity after the first surgery. Incipient regeneration potentials were detected in 4-17 months (average 7.6) and reached maximum in 6.5-18 months (average 16). Electromyographic assessment of the effect of tongue movement showed better mimic voluntary activity by swallowing or by moving the tongue up. There was no relationship between the start of activity and the interval to achieving maximal activity. CONCLUSION: Hemihypoglossal-facial nerve anastomosis is a safe procedure and it is an optimal solution for cases lacking a proximal stump or in the case of reconstruction in the second stage. Electromyography can predict initial reinnervation activity after reconstructive procedures. During subsequent follow-up it can help to discover insufficiently recovering patients, however clinical characteristics are crucial.

Otorhinolaryngology in the COVID-19 era: Are there significant differences between hospital-based and private practices?

OBJECTIVES: The COVID-19 disease has an incredible impact on both hospital-based and private practices in the field of otorhinolaryngology and head and neck surgery. Practical issues faced by both types of practices have not been well addressed in most studies. A national survey was conducted in April 2020 to identify the challenges faced by otorhinolaryngologists practicing in the Czech Republic. DESIGN: Prospective questionnaire-based study SETTING: Online Google questionnaire sent to the members of the Czech Society of Otorhinolaryngology and Head and Neck Surgery PARTICIPANTS: All doctors practicing Otorhinolaryngology in the Czech Republic with access to the online questionnaire between 15th and 26th April 2020. MAIN OUTCOME MEASURES: The primary aims of the study were to evaluate any significant differences between the two types of practice in the field of Otorhinolaryngology. We formulated null hypotheses stating there were no statistical differences in the preparation and availability of personal protective equipment amongst both practices a month after the first case of COVID-19 in the Czech Republic. Statistical analyses including the Mann-Whitney U test were performed to test the hypotheses. RESULTS: Analysis and results were based on the completion of the entire questionnaire by the doctors. There were no statistically significant differences between both the practices; however, individual analyses of both the practices showed a different outcome. CONCLUSION: Despite our statistical results, it was observed that private practices faced more deficits and were more financially vulnerable. They were also other issues reported by both practices that could compromise the care of patients, functioning of workplaces and support of doctors.

Extremely wicked, shockingly evil and undoubtedly COVID-19: the silent serial killer.

BACKGROUND: The SARS-COV-2 virus has more than just an infectious role to play in the society. The rapid spread has also led to significant personal, professional, financial and economic recession globally. Health care professionals are getting seriously compromised due to these issues. No published data are available on the indirect effects of COVID-19 on high-risk medical specialties. Otorhinolaryngology is considered as one such specialty. Hence, we designed a national survey to address these issues. MATERIALS AND METHODS: A google questionnaire was sent to all the otorhinolaryngologists in Czech Republic with the help of the Czech Society of Otorhinolaryngology and Head and Neck Surgery to evaluate the problems they encountered during the first wave of COVID-19. Personal, professional and financial losses were also addressed. Online access to the survey was from 15th April 2020 to 26th April 2020. RESULTS: The psychosomatic indirect impact of the disease affected female doctors than males. Burnout syndrome was the most commonly reported problem. Around 44.75% of all doctors had a combination of health, financial and economic as well as professional development and educational issues. Doctors from private practices faced higher financial losses. CONCLUSIONS: Our study showed that personal, professional and financial disturbances amongst doctors can lead to more serious consequences. With the lack of drastic measures in improving the support system for healthcare workers, the healthcare systems will fail quickly. Adequate support should be made mandatory by health authorities.

Face to face with COVID-19: highlights of challenges encountered in various ENT practices across the Czech Republic (a national survey).

The SARS-CoV-2 virus causing the COVID-19 disease created considerable complications and disruptions due to it's pandemic spread. The nature of the disease left certain clinical specialties more vulnerable than others, causing serious problems with organization of care of patients. Most studies concentrated on protocols and strategies to control the situation and reduce further spread amongst medical fields. Only few were designed to identify the various issues faced by doctors. We decided to design a questionnaire addressing relevant matters for doctors working in the field of ear, nose and throat (ENT). This was then sent to all the members of the Czech Society of Otorhinolaryngology. All ENT doctors were invited to fill out the survey within a stipulated time. The aim of the study was to evaluate the impact of a pandemic situation amongst such a high risk specialty. Our results showed a significant difference between the first cases of COVID-19 and progress of the disease during April 2020 in terms of workplace preparation, adequacy of personal protective equipment and other disposable aids. There was also inadequate support of medical personnel within the ENT practices. Furthermore, financial losses were also experienced due to mainly patient-related problems. In conclusion, the obtained results were used to formulate some recommendations for the public, patients, medical staff and employers. These suggestions will hopefully help avoid a repetition of the glitches if faced with another pandemic situation.

Prevalence of Fabry disease in men with tinnitus and sensorineural hearing loss.

Fabry disease (FD) is a lysosomal storage disorder caused by pathogenic mutations in the alpha-galactosidase A (AGALA) encoding gene region. This rare disease affects several organs including the cochlea-vestibular system. Tinnitus and sensorineural hearing loss (SNHL) are reported among otoneurological symptoms. Early and correct diagnosis of FD is important with a view to available therapy. The aim of the study was to screen for alpha-galactosidase deficiency in men with tinnitus/SNHL. A prospective multicentric study including consecutive patients with SNHL confirmed by tone audiometry or tinnitus evaluated (10/2016-8/2019). The diagnosis of AGALA deficiency was done by dry blood spot method using a threshold of 1.2 µmol/l/h. Only men aged 18-60 were included. 181 patients were subject to evaluation. SNHL was reported in 126 (70%) patients, 50 (28%) patients had unilateral, 76 (42%) patients had bilateral SNHL. Tinnitus was found in 161 (89%) patients, unilateral in 96 (53%) and bilateral in 65 (36%) patients. Suspected FD was not detected in any patient; alpha-galactosidase The AGALA values ranged 1.5-8.8 µmol/l/h, an average of 3.4 µmol/l/h. None of the 181 patients participating in the study had AGALA levels below the threshold 1.2 µmol/l/h. The occurrence of tinnitus and sensorineural hearing loss in men appears to be an irrelevant clinical sign for FD systematic screening.

Advanced Statistical Analysis of 3D Kinect Data: Mimetic Muscle Rehabilitation Following Head and Neck Surgeries Causing Facial Paresis.

An advanced statistical analysis of patients' faces after specific surgical procedures that temporarily negatively affect the patient's mimetic muscles is presented. For effective planning of rehabilitation, which typically lasts several months, it is crucial to correctly evaluate the improvement of the mimetic muscle function. The current way of describing the development of rehabilitation depends on the subjective opinion and expertise of the clinician and is not very precise concerning when the most common classification (House-Brackmann scale) is used. Our system is based on a stereovision Kinect camera and an advanced mathematical approach that objectively quantifies the mimetic muscle function independently of the clinician's opinion. To effectively deal with the complexity of the 3D camera input data and uncertainty of the evaluation process, we designed a three-stage data-analytic procedure combining the calculation of indicators determined by clinicians with advanced statistical methods including functional data analysis and ordinal (multiple) logistic regression. We worked with a dataset of 93 distinct patients and 122 sets of measurements. In comparison to the classification with the House-Brackmann scale the developed system is able to automatically monitor reinnervation of mimetic muscles giving us opportunity to discriminate even small improvements during the course of rehabilitation.

Lymph node metastasis of parotid gland high-grade adenoid-cystic carcinoma.

Adenoid cystic carcinoma (ACC) is one of the most common salivary gland malignancies. In rare cases, ACC undergoes high-grade transformation, which is associated with poor prognosis, in contrast to relatively long survival in the conventional ACC. Conventional ACC is characterized by typical histopathology showing glandular arrangement with sharply demarcated lumina, the tumor cells have sparse cytoplasm and angulated hyperchromatic nuclei. ACCs undergoing high-grade transformation lack these morphological features. In this paper we present a case of 46 years old female patient presenting with locally advanced tumor of the parotid gland and neck lymphadenopathy, coming for surgery. A suspect lymph node was sent to freeze section histology. Large non-cohesive cells with vesicular nuclei and prominent nucleoli along with well persevered lymph node architecture were seen in the frozen slide. This finding lead to suspicion of a lymphoma, the surgery finished in the extent of superficial parotidectomy and selective neck dissection of regions II-IV. Subsequent histopathological examination of formalin-fixed lymph node proofed epithelial nature of the atypical cells by p63 positivity. In the parotid gland resection specimen, an ACC with high-grade component was indentified. The high-grade ACC shared cell morphology with the lymph node metastasis. 17 from 20 lymph neck nodes contained metastases of high-grade ACC. Interestingly, there was strong CD117 expression in the high-grade ACC, whereas the conventional part was fully negative. To the best of our knowledge, the high-grade ACC of the parotid gland was reported only in 10 cases in the medical literature.

Syndromes that predispose to epistaxis.

PURPOSE: Our aim was to evaluate if epistaxis is directly associated with the etiology or pathophysiological mechanism which results in the syndrome itself or arises as a secondary effect. METHODS: We performed an extensive literature review of the web-based PubMed database from the National Library of Medicine to ascertain syndromes related to this condition. Etiology, pathophysiological mechanisms, occurrence, clinical features and management were noted for each of these syndromes. RESULTS: Epistaxis is commonly seen in syndromes that are usually directly related to vascular abnormalities or coagulation defects. However, in some cases, it is not. DISCUSSION AND CONCLUSION: Since a number of these syndromes are rare and elaborate tests are not carried out in the absence of a positive family history or until other specific clinical features appear, a risk of underdiagnosis and the dilemma of whether epistaxis is specifically related to the syndrome or a secondary effect still remains.

The evaluation of vestibular compensation by vestibular rehabilitation and prehabilitation in short-term postsurgical period in patients following surgical treatment of vestibular schwannoma.

PURPOSE: Vestibular schwannoma removal causes unilateral vestibular deafferentation, which results in dizziness and postural unsteadiness. Vertigo and balance problems together are among the most important aspects affecting quality of life. Intensive vestibular rehabilitation, which starts before surgery, with following postsurgical supervised rehabilitation, using visual biofeedback propose an instrument to accelerate a recovery process. Another option how to accelerate the vestibular compensation, is employment of presurgical gentamicin ablation together with vestibular rehabilitation (prehabilitation) of vestibular function. Purpose of present study was to examine the dynamics of vestibular compensation process using supervised intensive vestibular rehabilitation with visual biofeedback in the short-term postsurgical period. The second aim was to compare both studied groups mainly to evaluate if prehabilitation has potential to accelerate the compensation process in the early postoperative course. METHODS: The study included 52 patients who underwent the retrosigmoid vestibular schwannoma removal. They were divided into two groups. The first group was prehabilitated with intratympanic application of gentamicin before surgery to cause unilateral vestibular loss (14 patients), the second group (38 patients) was treated in standard protocol without prehabilitation. All patients underwent at home vestibular training before surgery to learn new movement patterns. Following the surgery supervised intensive vestibular rehabilitation including visual biofeedback was employed daily in both groups between the 5th and 14th postoperative day. Outcome measurements included an evaluation of subjective visual vertical (SVV), posturography and the Activities-Specific Balance Confidence Scale (ABC). ANOVA for repeated measurements was used for statistical analysis. RESULTS: We observed significant improvement in SVV (p < 0.05), posturography parameters (p < 0.05) and ABC scores (p < 0.05) with postoperative rehabilitation program following surgery in both groups. There was no statistically significant difference between group treated by prehabilitation and group without prehabilitation. CONCLUSIONS: Results of this study showed that intensive postsurgical rehabilitation represents key factor in compensation process following retrosigmoid vestibular schwannoma surgery. Prehabilitation did not speed up recovery process.

Tumors of the temporal bone.

Temporal bone tumors are rare entities. Histologically these pathologies represent heterogeneous group of diseases. The most common tumors of the temporal bone are vestibular schwannoma, tympanojugular paragangliomas and temporal bone carcinomas. Inner ear tumors, tumors of intratemporal segment of facial nerve and petrous bone tumors represent specific problematics. Clinical symptomatology reflects localization, extent of temporal bone invasion and involvement of individual temporal bone structures. Atypical symptomatology, dysfunction of the cranial nerves of the temporal bone and clustering of inner and middle ear symptoms are key warning signs. Imaging methods, audiometric, neurootological, and neurophysiological examinations are crucial for diagnosis and therapeutic decision planning. Modern therapeutic approaches are dictated by improved understanding of the biology of different tumors and follow recommended guidelines. The treatment is multidisciplinary in many aspects. Surgical treatment requires specific equipment, experience and accumulation of adequate number of cases, therefore it is realized in specialized centers. Unique surgical approaches from the spectrum of neurootologic surgery and skull base surgery are employed.

Baha implant as a hearing solution for single-sided deafness after retrosigmoid approach for the vestibular schwannoma: audiological results.

Skull base tumors and, in particular, vestibular schwannoma (VS) are among the etiological reasons for single-sided deafness (SSD). Patients with SSD have problems in understanding speech in a noisy environment and cannot localize the direction of sounds. For the majority, this is the handicap for which they try to find a solution. Apart from CROS hearing aids, Baha is one of the most frequently used systems for SSD compensation. 38 patients with single-sided deafness after retrosigmoid removal of a vestibular schwannoma underwent testing with a Baha softband from September 2010 to August 2014. Sixteen patients (42 %) finally decided to accept Baha implantation. Subjective experience with the Baha softband was evaluated by patients using the BBSS questionnaire immediately after testing. Objective evaluation of the effect was performed as a measurement of the sentence discrimination score in noise and side horizontal discrimination without a Baha and 6 weeks and 12 months after a sound processor fitting. There was a significant improvement in sentence discrimination in the 6 week (64.0 %) and 1 year (74.6 %) interval of follow-up in comparison with understanding without Baha (24.0 %, p = 0.001) in situations when sentences are coming from the side of the non-hearing ear and noise contralaterally with SNR -5 dB. Baha can significantly improve sentence discrimination in complex-listening situation in patients with SSD after the VS surgery.

Baha implant as a hearing solution for single-sided deafness after retrosigmoid approach for the vestibular schwannoma: surgical results.

Skull base tumors and, in particular, vestibular schwannoma (VS) are among the etiological reasons for single-sided deafness (SSD). Patients with SSD have problems in understanding speech in a noisy environment and cannot localize the direction of sounds. Baha is one of the most frequently used systems for SSD compensation. Out of 38 patients with SSD after retrosigmoid removal of VS who underwent testing with Baha softband, 16 were satisfied and were indicated for Baha implantation. Two surgical approaches have been used-the Nijmegen linear incision technique with subdermal thinning (Group I, implant BI300) and fast surgery technique without subdermal thinning (Group II, implant BIA400). The duration of the surgery, the implant stability measured by Ostell, and skin or soft tissue reactions in long range follow-up were evaluated and compared between Group I and II. There was a difference in duration of surgery, in Group II procedures averaged significantly faster (p > 0.001). In both groups, there was a similar trend of the gradual increase of implant stability. In the Group I and II, there was comparable rate of the skin or soft tissue reactions grade 0, I, II, or III. We have proved Baha to be a suitable possibility for SSD patients after the removal of VS, regardless of the approach. After the retrosigmoid approach to the VS, the key step of Baha implantation must be to reach intact healthy bone to avoid implantation into scar tissue.

Cancer Microenvironment: What Can We Learn from the Stem Cell Niche.

Epidermal stem cells (ESCs) are crucial for maintenance and self- renewal of skin epithelium and also for regular hair cycling. Their role in wound healing is also indispensable. ESCs reside in a defined outer root sheath portion of hair follicle-also known as the bulge region. ECS are also found between basal cells of the interfollicular epidermis or mucous membranes. The non-epithelial elements such as mesenchymal stem cell-like elements of dermis or surrounding adipose tissue can also contribute to this niche formation. Cancer stem cells (CSCs) participate in formation of common epithelial malignant diseases such as basal cell or squamous cell carcinoma. In this review article, we focus on the role of cancer microenvironment with emphasis on the effect of cancer-associated fibroblasts (CAFs). This model reflects various biological aspects of interaction between cancer cell and CAFs with multiple parallels to interaction of normal epidermal stem cells and their niche. The complexity of intercellular interactions within tumor stroma is depicted on example of malignant melanoma, where keratinocytes also contribute the microenvironmental landscape during early phase of tumor progression. Interactions seen in normal bulge region can therefore be an important source of information for proper understanding to melanoma. The therapeutic consequences of targeting of microenvironment in anticancer therapy and for improved wound healing are included to article.

Gait disorder classification based on effective feature selection and unsupervised methodology.

In gait stability analysis, patients suffering from dysfunction problems are impacted by shifts in their dynamic balance. Monitoring the patients' progress is important for allowing physicians and patients to observe the rehabilitation process accurately. In this study, we designed a new methodology for classifying gait disorders to quantify patients' progress. The dataset in this study includes 84 measurements of 37 patients based on a physician's opinion. In this study, the system, which includes a Kinect camera to observe and store the frames of patients walking down a hallway, a key-point detector to detect the skeletal key points, and an encoder transformer classifier network integrated with generator-discriminator networks (ET-GD), is designed to evaluate the classification of gait dysfunction. The detector extracts the skeletal key points of patients. After feature engineering, the selected high-level features are fed into the proposed neural network to analyse patient movement and perform the final evaluation of gait dysfunction. The proposed network is inspired by the 1D encoder transformer, which is integrated with two main networks: a network for classification and a network to generate fake output data similar to the input data. Furthermore, we used a discriminator structure to distinguish between the actual data (input) and fake data (generated data). Due to the multi-structural networks in the proposed method, multi-loss functions need to be optimised; this increases the accuracy of the encoder transformer classifier.

Upregulation of IL-6, IL-8 and CXCL-1 production in dermal fibroblasts by normal/malignant epithelial cells in vitro: Immunohistochemical and transcriptomic analyses.

BACKGROUND INFORMATION: Considering an analogy between wound healing and tumour progression, we studied chemokine and cytokine transcription and expression in normal fibroblasts by co-culture and in situ. RESULTS: Whole-genome transcriptome profiling revealed strong upregulation for the interleukin (IL)-6, IL-8 and the chemokine CXCL-1 in in vitro co-cultures of normal fibroblasts with either normal or malignant epithelial cells compared to fibroblast cultures. The same ILs/chemokines were distinctly upregulated in clinical samples of squamous cell carcinoma when compared with paired normal mucosae. Analysis of culture supernatants showed that during the course of co-culture of the fibroblasts with the epithelial cells, IL-6, IL-8 and CXCL-1 were secreted to the culture medium. Experiments with addition of any of the proteins to the culture medium supported the notion that these ILs/chemokines strongly contributed to maintenance of a low-differentiation phenotype of epithelial cells, evaluated by the detection of keratin-8. Simultaneous addition of all factors increased the extent of the effect. These studies were extended by experiments with epithelial cells, either cultured in medium conditioned by preceding use for malignant keratinocytes without and in the presence of normal or cancer-associated fibroblasts or medium containing antibodies against IL-6, IL-8 and CXCL-1. CONCLUSIONS: Our results indicate an analogy between wound healing and tumour growth, support the importance of epithelial-mesenchymal interaction in this model system and establish a potential bio-inspired anticancer therapy.

Loss of adhesion/growth-regulatory galectin-9 from squamous cell epithelium in head and neck carcinomas.

Galectins are potent effectors of cell adhesion and growth regulation. Their expression as comples network necessitates systematic study of each member of this family. Toward this aim, we here focus on the tandem-repeat-type galectin-9. Its presence is monitored in normal squamous epithelium of the head and neck, the surgical margin, and four types of squamous cell carcinoma. Lectin presence was detected in cells of the basal layer of the epithelium. All galectin-9-negative epithelia showed aberrant positivity for keratins 14 and 19. The surgical margin presented either a normal pattern of galectin-9 and keratin presence or a mosaic-like presence/absence of galectin-9 and aberrant expression of both keratins 14 and 19. All studied specimens of squamous cell carcinoma were negative for galectin-9. When biotinylated galectin-9, or its N-terminal domain, was tested, no significant tissue reactivity for both probes was observed. Neuraminidase treatment generated reactivity to the N-domain. In conclusion, galectin-9 is expressed in the majority of samples of normal epithelium, along with regular presence of keratins 14 or 19. This lectin can represent a potential marker of normality in the cases of the studied squamous cell epithelia.

Impact of video-endoscopy on the results of retrosigmoid-transmeatal microsurgery of vestibular schwannoma: prospective study.

Endoscopy-assisted microsurgery represents modern trend of treatment of the cerebellopontine angle (CPA) pathologies including vestibular schwannoma (VS). Endoscopes are used in adjunct to microscope to achieve better functional results with less morbidity. Angled optics, magnification and illumination enable superior view in the operative field. Consecutive 89 patients with untreated unilateral sporadic vestibular schwannoma undergoing tumor resection via a retrosigmoid approach during 2008-2010 were prospectively analysed. Endoscopy-assisted microsurgical (EA-MS) removal was performed in 39 cases (Grade 1: 2, Grade 2: 5, Grade 3: 9, Grade 4: 22, Grade 5: 1) and microsurgical (MS) removal was performed in 50 cases (Grade 1: 1, Grade 2: 3, Grade 3: 9, Grade 4: 34, Grade 5: 3). Minimally invasive approach with craniotomy ≤ 2.5 cm was employed for small tumors (Grade 1 and 2) in the EA-MS group. Endoscopic technique was used for monitoring of neuro-vascular anatomy in CPA, during dissection of the meatal portion of tumors, assessment of radicality and for identification of potential pathways for CSF leak formation. All cases in MS group were deemed as radically removed. In the EA-MS group, residual tumor tissue in the fundus of internal auditory canal not observable with microscope was identified with endoscope in four cases. Such cases were radicalized. Tumor recurrence was not observed during the follow-up in EA-MS group. There is a suspicious intrameatal tumor recurrence on the repeated MRI scan in one patient in the MS group. Neither mortality nor infection was observed. The most common complication was pseudomeningocele (EA-MS 20 cases; MS 23). It was managed with aspiration with or without tissue-gluing in all cases without the need for any surgical revision. Adjunctive use of endoscope in the EA-MS group identified potential pathways for CSF leak formation, which was not observable with the microscope in five patients. Improved cochlear nerve (EA-MS: 22, MS: 14; p = 0.012), brainstem auditory evoked potentials (EA-MS: 3 of 8, MS: 0 of 4) and hearing (EA-MS: 14 of 36, MS: 4 of 45; p = 0.001) preservation were observed in EA-MS group. Despite the trend for better useful hearing (Gardner-Robertson class 1 and 2) preservation (EA-MS: 8 of 26, MS: 1 of 16) there were no significant differences in the postoperative hearing handicap inventory in both groups. There were no differences in the postoperative tinnitus in both groups. Better facial nerve preservation (EA-MS: 39, MS: 44; p = 0.027) and excellent-very good (House-Brackmann 1 or 2) facial nerve function (EA-MS: 31, MS: 29; p = 0.035) were observed in EA-MS group. Postoperative compensation of vestibular lesion, symptoms typical for VS, patients assessed by dizziness handicap inventory, facial disability index were comparable in both studied groups. Adjunctive use of endoscope during the VS surgery due to its magnification and illumination enable superior view in the operative field. It is valuable for assessment of radicality of resection in the region of internal auditory meatus. Improved information about critical structures and tumor itself helps the surgeon to preserve facial nerve and in selected cases also hearing. These techniques can help to decrease incidence of postoperative complications.

Binocular video head impulse test: Normative data study.

Introduction: The video head impulse test (vHIT) evaluates the vestibulo-ocular reflex (VOR). It's usually recorded from only one eye. Newer vHIT devices allow a binocular quantification of the VOR. Purpose Aim: To investigate the advantages of simultaneously recorded binocular vHIT (bvHIT) to detect the differences between the VOR gains of the adducting and the abducting eye, to define the most precise VOR measure, and to assess gaze dys/conjugacy. We aimed to establish normative values for bvHIT adducting/abducting eye VOR gains and to introduce the VOR dysconjugacy ratio (vorDR) between adducting and abducting eyes for bvHIT. Methods: We enrolled 44 healthy adult participants in a cross-sectional, prospective study using a repeated-measures design to assess test-retest reliability. A binocular EyeSeeCam Sci 2 device was used to simultaneously record bvHIT from both eyes during impulsive head stimulation in the horizontal plane. Results: Pooled bvHIT retest gains of the adducting eye significantly exceeded those of the abducting eye (mean (SD): 1.08 (SD = 0.06), 0.95 (SD = 0.06), respectively). Both adduction and abduction gains showed similar variability, suggesting comparable precision and therefore equal suitability for VOR asymmetry assessment. The pooled vorDR here introduced to bvHIT was 1.13 (SD = 0.05). The test-retest repeatability coefficient was 0.06. Conclusion: Our study provides normative values reflecting the conjugacy of eye movement responses to horizontal bvHIT in healthy participants. The results were similar to a previous study using the gold-standard scleral search coil, which also reported greater VOR gains in the adducting than in the abducting eye. In analogy to the analysis of saccade conjugacy, we propose the use of a novel bvHIT dysconjugacy ratio to assess dys/conjugacy of VOR-induced eye movements. In addition, to accurately assess VOR asymmetry, and to avoid directional gain preponderance between adduction and abduction VOR-induced eye movements leading to monocular vHIT bias, we recommend using a binocular ductional VOR asymmetry index that compares the VOR gains of only the abduction or only the adduction movements of both eyes.

The effect of aging, hearing loss, and tinnitus on white matter in the human auditory system revealed with fixel-based analysis.

Introduction: Aging negatively influences the structure of the human brain including the white matter. The objective of our study was to identify, using fixel-based morphometry, the age induced changes in the pathways connecting several regions of the central auditory system (inferior colliculus, Heschl's gyrus, planum temporale) and the pathways connecting these structures with parts of the limbic system (anterior insula, hippocampus and amygdala). In addition, we were interested in the extent to which the integrity of these pathways is influenced by hearing loss and tinnitus. Methods: Tractographic data were acquired using a 3 T MRI in 79 volunteers. The participants were categorized into multiple groups in accordance with their age, auditory thresholds and tinnitus status. Fixel-based analysis was utilized to identify alterations in the subsequent three parameters: logarithm of fiber cross-section, fiber density, fiber density and cross-section. Two modes of analysis were used: whole brain analysis and targeted analysis using fixel mask, corresponding to the pathways connecting the aforementioned structures. Results: A significantly negative effect of aging was present for all fixel-based metrics, namely the logarithm of the fiber cross-section, (7 % fixels in whole-brain, 14% fixels in fixel mask), fiber density (5 % fixels in whole-brain, 15% fixels in fixel mask), fiber density and cross section (7 % fixels in whole-brain, 19% fixels in fixel mask). Expressed age-related losses, exceeding 30% fixels, were particularly present in pathways connecting the auditory structures with limbic structures. The effect of hearing loss and/or tinnitus did not reach significance. Conclusions: Our results show that although an age-related reduction of fibers is present in pathways connecting several auditory regions, the connections of these structures with limbic structures are even more reduced. To what extent this fact influences the symptoms of presbycusis, such as decreased speech comprehension, especially in noise conditions, remains to be elucidated.