Ultrarare heterozygous pathogenic variants of genes causing dominant forms of early-onset deafness underlie severe presbycusis.

Presbycusis, or age-related hearing loss (ARHL), is a major public health issue. About half the phenotypic variance has been attributed to genetic factors. Here, we assessed the contribution to presbycusis of ultrarare pathogenic variants, considered indicative of Mendelian forms. We focused on severe presbycusis without environmental or comorbidity risk factors and studied multiplex family age-related hearing loss (mARHL) and simplex/sporadic age-related hearing loss (sARHL) cases and controls with normal hearing by whole-exome sequencing. Ultrarare variants (allele frequency [AF] < 0.0001) of 35 genes responsible for autosomal dominant early-onset forms of deafness, predicted to be pathogenic, were detected in 25.7% of mARHL and 22.7% of sARHL cases vs. 7.5% of controls (P = 0.001); half were previously unknown (AF < 0.000002). MYO6, MYO7A, PTPRQ, and TECTA variants were present in 8.9% of ARHL cases but less than 1% of controls. Evidence for a causal role of variants in presbycusis was provided by pathogenicity prediction programs, documented haploinsufficiency, three-dimensional structure/function analyses, cell biology experiments, and reported early effects. We also established Tmc1N321I/+ mice, carrying the TMC1:p.(Asn327Ile) variant detected in an mARHL case, as a mouse model for a monogenic form of presbycusis. Deafness gene variants can thus result in a continuum of auditory phenotypes. Our findings demonstrate that the genetics of presbycusis is shaped by not only well-studied polygenic risk factors of small effect size revealed by common variants but also, ultrarare variants likely resulting in monogenic forms, thereby paving the way for treatment with emerging inner ear gene therapy.

Balloon dilation for persistent unilateral chronic obstructive Eustachian tube dysfunction is effective: a prospective multicentre study.

PURPOSE: Balloon dilatation of the Eustachian tube (BDET) is an option for treating chronic obstructive Eustachian tube dysfunction (COETD). In this prospective multicentric study, the main objective was to evaluate the results of BDET in unilateral COETD refractory to medical treatment. METHODS: Adults with unilateral COETD whose Eustachian Tube Score (ETS) was less than 5 despite medical pressure therapy were included. The primary endpoint was the change in ETS measured at 2, 6, and 12 months after BDET. Secondary objectives were the evolution of clinical symptoms assessed by the Eustachian Tube Questionnaire (ETDQ-7), audiometry, tympanometry, and otoscopy changes after BDET. RESULTS: Twenty-eight patients were included between May 2014 and December 2017 and were treated with BDET without adverse effects in three different referral centers. Population's median age was 52 (Q25; Q75: 24, 82) years. The median follow-up time was 381 (Q25; Q75: 364; 418) days. The median ETS was 2 (Q25; Q75: 1; 4) before BDET. There was a significant improvement in ETS at 2 and 6 months and 1 year after BDET (score at 1 year: 6 (Q25; Q75: 2; 8) (p < 0.0001)). There was a significant, sustained improvement in the ETDQ-7 with a score of 4.21 (Q25; Q75-3.50; 4.79) before BDET and 3.43 (Q25; Q75-2.43; 4.14) (p = 0.0012) at 1 year. There was a suggestive improvement in tympanometry results at 1 year (p = 0.025). CONCLUSION: BDET provides an improvement in symptoms and objective measures assessed at 1 year in patients with COETD who have failed medical treatment. TRIAL REGISTRATION: NCT02123277 (April 25, 2014).

Is salvage surgery for large vestibular schwannomas after failed gamma knife radiosurgery more challenging?

In order to verify whether a previous gamma knife surgery (GKS) treatment could influence the oncological and functional outcome in large vestibular schwannoma (VS) surgery, we have compared group of patients operated on for large VS after failed GKS to a group of genuine VS that underwent the same functional nerve-sparing resection technique regimen in the same period. Single center retrospective cohort study of 23 consecutive GKS failure and 170 genuine VS patients operated on between April 2003 and March 2019. After resection, patients were allocated to a Wait-&-rescan or an upfront GKS policy. At last follow-up examination, the facial nerve function was good (House-Brackmann grades I or II) in 95% of the GKS failure and 84% of the genuine VS patients (p = .25). The median volume of tumor residue was .56 cc in the GKS failure group and .62 cc in the genuine VS group (p = .70). Tumor control was achieved in 91% and 83% of cases with a mean follow-up of 74 and 63 months in the GKS failure and the genuine VS populations, respectively. The 1-, 5-, and 7-year progression-free survival were 100%, 95%, and 85% respectively in the GKS failure group and 97%, 80%, and 81% in the genuine VS group (p = .27). Despite significant modifications of the microsurgical environment associated to salvage surgery after GKS failure, a functional nerve-sparing resection is an effective strategy to optimize the results on facial nerve function, with similar long-term tumor control to those observed in the genuine VS population.

Signs of spatial neglect in unilateral peripheral vestibulopathy.

BACKGROUND AND PURPOSE: In this study, the question of whether egocentric representation of space is impaired in chronic unilateral vestibulopathies was examined. The objective was to test current theories attributing a predominant role to vestibular afferents in spatial cognition and to assess whether representational neglect signs are common in peripheral vestibular loss. METHODS: The subjective straight-ahead (SSA) direction was investigated using a horizontal rod allowing the translation and rotation components of the body midline representation to be dissociated in 21 patients with unilateral vestibular loss (right, 13; left, eight) and in 12 healthy controls. RESULTS: Compared to the controls, the patients with unilateral vestibulopathy showed a translation bias of their SSA, without rotation bias. The translation bias was not lateralized towards the lesioned side as typically found for biases reported after unilateral vestibular loss. Rather, the SSA bias was rightward whatever the side of the vestibular loss. The translation bias correlated with the vestibular loss, as measured by caloric response and vestibulo-ocular reflex gain, but not with the subjective visual vertical or the residual spontaneous nystagmus. CONCLUSION: The present data suggest that the dysfunctions of neural networks involved in egocentred and allocentred representations of space are differentially compensated for in unilateral vestibular defective patients. In particular, they suggest that asymmetrical vestibular inputs to cortical regions lead to representational spatial disturbances as does defective cortical processing of vestibular inputs in spatial neglect after right hemisphere stroke. They also highlight the predominant role of symmetrical and unaltered vestibular inputs in spatial cognition.

Does NF2 status impact the results of combined surgery and adjunctive Gamma Knife surgery for large vestibular schwannomas?

In order to verify whether neurofibromatosis type 2 (NF2) could influence the oncological and functional outcome in large vestibular schwannoma (VS) surgery, we compared a group of NF2 patients operated with a facial nerve-sparing technique to a group of sporadic VSs of similar volume that underwent the same treatment regimen in the same period. Single-center retrospective cohort study about 12 consecutive NF2 and 69 non-NF2 patients operated on for large VS between September 2006 and November 2016. After resection, patients were allocated to an upfront Gamma Knife surgery policy of the tumor residue. At last follow-up examination, the facial nerve function was good (House-Brackmann grades I or II) in 92% of the NF2 and 83% of the non-NF2 patients (p = .90). The median volume of tumor residue was .92 cc in the NF2 group and .54 cc in the non-NF2 group (p = .14). Tumor control was achieved in 83% and 81% of cases in the NF2 and the non-NF2 populations, respectively, with a mean follow-up of 73 months in both groups. The 1-, 5-, and 7-year progression-free survival were 92%, 83%, and 83% respectively in the NF2 group, and 99%, 83%, and 80% in the non-NF2 group (p = .96). Our analysis of 12 NF2 and 69 non-NF2 patients operated on by the same surgical team with the same treatment regimen did not show any functional or tumor control difference between those groups.

Intratemporal facial nerve schwannomas: multicenter experience of 80 cases.

PURPOSE: To provide more data on the clinical presentation and natural evolution of facial nerve schwannomas and to provide guidance for therapeutic decision making. METHODS: A retrospective case review of eighty patients diagnosed with a facial nerve schwannoma between 1990 and 2018 in ten tertiary referral centers in Europe was performed. Patients' demographics, symptomatology, audiometry, anatomical site (segments involved), size and whenever possible volume measurement were registered. RESULTS: At presentation, transient or persistent facial palsy was the most common symptom, followed by hearing loss. The schwannoma involved more than one segment in the majority of the patients with the geniculate ganglion being most commonly involved. Initial treatment consisted of a wait and scan approach in 67.5%, surgery in 30% and radiation therapy in 2.5% of the patients. Tympanic segment schwannomas caused mainly conductive hearing loss and were more prone to develop facial palsy at follow-up. Internal auditory canal or cerebellopontine angle schwannomas presented with significantly more sensorineural hearing loss. CONCLUSIONS: Although modern imaging has improved diagnosis of this tumor, choosing the best treatment modality remains a real challenge. Based on the literature review and current findings, more insights into the clinical course and the management of facial nerve schwannomas are provided.

Exploring the link between tumour metabolism and succinate dehydrogenase deficiency: A 18 F-FDOPA PET/CT study in head and neck paragangliomas.

OBJECTIVES: Nuclear imaging findings by virtue of phenotyping disease heavily depend on genetic background, metabolites, cell membrane specific targets and signalling pathways. PPGL related to succinate dehydrogenase subunits mutations (SDHx mutations) are less differentiated than other subgroups and therefore may lack to concentrate 18 F-FDOPA, a precursor of catecholamines biosynthesis. However, this 18 F-FDOPA negative phenotype has been reported mostly in SDHx-PPGL of sympathetic origin, suggesting that both genotype status and location (from sympathetic vs parasympathetic paraganglia; adrenal vs extra-adrenal) could influence 18 F-FDOPA uptake. The aim of this study was to test if SDHx drives 18 F-FDOPA uptake in presence of normal epinephrine/norepinephrine concentrations. DESIGN: Retrospective study PATIENTS: A cohort of 86 head and neck PPGL patients (including three metastatic) with normal metanephrines underwent 18 F-FDOPA PET/CT. The relationships between 18 F-FDOPA uptake and tumour genotype were evaluated. RESULTS: In nonmetastatic HNPGL (50 non-SDHx/33 SDHx), no significant difference was observed between these two groups for SUVmax (P = .256), SUVmean (P = .188), MTV 42% (P = .596) and total lesion uptake (P = .144). Metastatic HNPGL also had high elevated uptake values. CONCLUSIONS: Our results suggest that SDH deficiency or metastatic behaviour have no influence on 18 F-FDOPA uptake in HNPGL probably due to their very-well differentiation status, even at metastatic stage. The potential prognosticator value of 18 F-FDOPA uptake would need to be further explored in the setting of metastatic PPGL of sympathetic origin.

Validation of French versions of the Facial Disability Index and the Facial Clinimetric Evaluation Scale, specific quality of life scales for peripheral facial palsy patients.

OBJECTIVES: To translate and validate French versions of two health-related quality of life questionnaires for patients with peripheral facial palsy: Facial Disability Index (FDI) and Facial Clinimetric Evaluation (FaCE) scale. DESIGN: Prospective cohort study. SETTING: University tertiary referral centre. PARTICIPANTS: A pilot test was performed on 10 subjects (5 patients with facial palsy of more than 1-month duration and 5 normal subjects), and then 67 adult patients with facial palsy were enrolled in the validation study. MAIN OUTCOME MEASURES: Translation of the original questionnaires has followed international guidelines using a forward-backward translation method. A pilot test and a validation study based on the translated questionnaires were performed. Internal consistency, test-retest reliability, validity and responsiveness were assessed. Validity was assessed by comparing to SF-36 and Sunnybrook/House-Brackmann grading systems. Subjects answered scales twice within a one-week interval. RESULTS: Sixty-seven patients were enrolled, among which 63 completed scales one week later (retest). For physical and social functions of FDI and FaCE scores, Cronbach's α representing internal consistency was 0.88, 0.70 and 0.89, and test-retest reliability by intra-class correlation coefficients was 0.81, 0.86 and 0.89, respectively. The correlation of facial movement score of FaCE scale was good with Sunnybrook/House-Brackmann grading systems (0.73 and -0.75, P < 0.01). The correlation of social function of FaCE scale was excellent with social function of SF-36 (0.8, P < 0.01). CONCLUSIONS: French versions of FDI and FaCE scale are psychometrically valid. Both questionnaires can be used for clinical studies to assess the quality of life of patients with peripheral facial palsy.

How I do it: the combined petrosectomy.

BACKGROUND: Petroclival and ventral brain stem tumors require a complex approach. METHOD: The combined petrosectomy is an epidural transtentorial-transpetrosal otoneurosurgical approach to achieve a retrolabyrinthine presigmoidal approach and an anterior petrosectomy in one single procedure. The different steps of this approach are described and illustrated by figures and a video. The indications and limitations of the technique are presented. CONCLUSION: The combined petrosectomy offers multiple corridors to the petroclival region and ventral brainstem while preserving the intrapetrous neurotological structures. Meticulous stepwise bony resection optimizing the dural opening and preservation of veins contributes to reducing the risk inherent to this technique.

Histological identification of nasopharyngeal mechanoreceptors.

The auditory tube plays a fundamental role in regulating middle ear pressure. A "system" sensitive to a pressure gradient between the middle ear and the ambient environment is necessary. The presence of mechanoreceptors in the middle ear and the tympanic membrane has been studied, but the presence of these receptors in the nasopharyngeal region remains unclear. The aim of this study is to confirm the presence of pressure sensitive corpuscles in the nasopharynx. An experimental study was conducted on five fresh and unembalded human cadavers. The pharyngeal ostium of the auditory tube and its periphery was removed in one piece by video-assisted endonasal endoscopy. Samples were fixed in formaldehyde solution, embedded in paraffin, and cut. Slides were analyzed by HES (Hematoxyline Eosine Safran) coloration, by S100 protein and neurofilament protein immunostaining. Encapsulated nerve endings were researched and identified by slides analysis. Eight samples were included in our study. On seven samples, Ruffini corpuscles were identified in the mucosa of the posterior area of the pharyngeal ostium, with a higher concentration in the pharyngeal recess and in the posterior nasopharyngeal wall. Our study identified nasopharyngeal mechanoreceptors that could detect the nasopharyngeal pressure and, by extension, the atmospheric pressure. These findings support the theory of the neuronal reflex arc of isobaric system of the middle ear, based on the existence of a "system" sensitive to a pressure gradient between the middle ear and the ambient environment. Understanding of this system has been helpful in the diagnosis and management of middle ear diseases.

Clinical evaluation of the xDP output compression strategy for cochlear implants.

Technological advances in the domain of digital signal processing adapted to cochlear implants (CI) are partially responsible for the ever-improving outcomes observed with this neural prosthesis. The goal of the present study was to evaluate audiometric outcomes with a new signal processing strategy implemented in Oticon Medical-Neurelec cochlear implant systems, the xDP strategy. The core of this approach is a preset-based back-end output compression system, modulating a multi-channel transfer function depending on the intensity and information content of input sounds. Twenty adult CI patients, matched for age and CI experience, were included in this study. Pure-tone thresholds and vocal audiometry scores were measured with their former signal processing strategy and with xDP. Speech perception was assessed using dissyllabic words presented in quiet, at different intensity levels: 40, 55, 70, and 85 dB SPL, and in a cocktail party noise at a signal-to-noise ratio of +10 dB. Results with the xDP strategy showed, as awaited, no major modification of pure-tone thresholds. A global increase of speech perception scores was observed after a 1-month habituation period, with significant improvements for speech perception in quiet for moderate (55 dB SPL), loud speech sounds (85 dB SPL), and speech-in-noise comprehension. Subjective signal quality assessment showed a preference for Crystalis(xDP) over the former strategy. These results allow the quantification of improvements provided by the xDP signal processing strategy.

The Voice Track multiband single-channel modified Wiener-filter noise reduction system for cochlear implants: patients' outcomes and subjective appraisal.

OBJECTIVE: The aim of this study was to evaluate the potential improvements of speech perception and sound quality provided by a multiband single channel noise-reduction algorithm based on the modified Wiener-filter adapted to cochlear implant sound processing. DESIGN: This study was a longitudinal trial with a repeated-measures design. Outcome measures were performed on the first day when the noise reduction feature was provided and after a one month habituation period. Objective measures included pure-tone thresholds and vocal audiometry assessments. Speech perception was measured in quiet and in the presence of two types of noise: a stationary speech shaped noise and a two-talker cocktail noise. Subjective sound quality was assessed using a ten item questionnaire. STUDY SAMPLE: Thirteen post-lingual deaf adults, experienced users of a cochlear implant system, took part in this study. RESULTS: The noise-reduction algorithm provided a benefit for the perception of speech presented in a stationary speech shaped noise and an overall improvement in subjective sound quality ratings. CONCLUSIONS: It was shown that a single channel noise reduction system based on a modified Wiener-filter approach can improve speech in noise perception performance and subjective sound quality in cochlear implant patients.

Temporal bone fractures: sequelae and their impact on quality of life.

PURPOSE: To present a prospective temporal bone fracture database, and study facial and cochleovestibular sequelae and their impact on quality of life. MATERIALS AND METHODS: Prospective study of consecutive cases of 39 patients with 45 temporal bone fractures over 11-month period in a university tertiary referral center. Based on epidemiological data, clinical and imaging findings, treatment modalities and outcome of patients with follow-up of one year, the present study focused on facial and cochleovestibular sequelae and their impact on quality of life after one-year period. RESULTS: After 12 months, 44% of patients present with balance problems, 56% with hypoacusis, 56% with tinnitus, and 15% with facial paralysis. In 75%-80% of patients, the cochleovestibular sequelae are described as disabling. Post-trauma quality of life was significantly impaired compared with pre-trauma quality of life, even after 12 months. Long-term cochleovestibular sequelae were significantly associated with poor long-term quality of life. CONCLUSIONS: The study demonstrates the need to focus on prevention of temporal bone fractures, notably by promoting the use of helmets and improvements in helmet design. The rapid diagnosis of temporal bone fracture is crucial as it enables effective initial management aimed at avoiding sequelae. The frequency of cochleovestibular sequelae after temporal bone fracture and their impact on quality of life demonstrate the importance of, and need for, ongoing follow-up by a local medical team who can diagnose and manage these long-term sequelae.

Vitamin D3 potentiates myelination and recovery after facial nerve injury.

Roles of vitamin D on the immune and nervous systems are increasingly recognized. Two previous studies demonstrated that ergocalciferol (vitamin D2) or cholecalciferol (vitamin D3) induced functional recovery and increased myelination in a rat model of peroneal nerve transection. The current report assessed whether cholecalciferol was efficient in repairing transected rabbit facial nerves. Animals were randomized into two groups of rabbits with an unilateral facial nerve surgery: the vitamin D group included animals receiving a weekly oral bolus of vitamin D3 (200 IU/kg/day), from day 1 post-surgery; the control group included animals receiving a weekly oral bolus of vehicle (triglycerides). Contralateral unsectioned facial nerves from all experimental animals were used as controls for the histological study. The facial functional index was measured every week while the inner diameter of myelin sheath and the G ratio were quantified at the end of the 3 month experiment. The current report indicates that cholecalciferol significantly increases functional recovery and myelination, after 12 weeks of treatment. To the best of our knowledge, this is the first study investigating the therapeutic benefit of vitamin D supplementation in an animal model of facial paralysis. It paves further the way for clinical trials based on the administration of this steroid in individuals with injured facial nerves.

Multicenter evaluation of Neurelec Digisonic® SP cochlear implant reliability.

Over the past decade, the adoption of universal hearing screening in newborns has led to earlier detection of hearing problems and significant lowering of the age of first cochlear implantation. As a consequence, recipients are now expected to keep their cochlear implants (CIs) for a longer period of time. Comprehensive longitudinal information on CI reliability is essential for device choice. The aim of this study was to assess the reliability (in children and adults) of the latest generation of the Digisonic(®) SP CI launched in 2006 by Neurelec. Failure rate (FR) and cumulative survival rate (CSR) for a 5-year period were calculated. This survey is a multicenter retrospective study. A questionnaire was sent to nine CI centers requesting information about patients implanted with Neurelec Digisonic(®) SP CIs. FR and CSR over a 5-year period were calculated on this group. Collaborating centers collected data on 672 patients (362 children and 310 adults) implanted between March 2006 and March 2011. The overall rate of explantation was 2.23 % (15 cases): six devices were explanted due to device failure (0.89 %) and nine were explanted for medical reasons (1.34 %). Four patients were lost to follow-up. The CSR at 5 years was 98.51 % on all patients, 98.48 % for children and 98.57 % for adults. FR was 0.97 % for adults and 0.83 % for children. This first independent study that assesses FR and CSR on the current generation of Digisonic(®) SP CI represents an important resource that can help clinicians and patients during their device choice.

Identification of Follow-Up Markers for Rehabilitation Management in Patients with Vestibular Schwannoma.

This study delves into the absence of prognostic or predictive markers to guide rehabilitation in patients afflicted with vestibular schwannomas. The objective is to analyze the reweighting of subjective and instrumental indicators following surgery, at 7 days and 1 month postoperatively. This retrospective cohort encompasses 32 patients who underwent unilateral vestibular schwannoma surgery at the Marseille University Hospital between 2014 and 2019. Variations in 54 indicators and their adherence to available norms are calculated. After 1 month, one-third of patients do not regain the norm for all indicators. However, the rates of variation unveil specific responses linked to a preoperative error signal, stemming from years of tumor adaptation. This adaptation is reflected in a postoperative visual or proprioceptive preference for certain patients. Further studies are needed to clarify error signals according to lesion types. The approach based on variations in normative indicators appears relevant for post-surgical monitoring and physiotherapy.

Place of Tubomanometry in Patulous Eustachian Tube Diagnosis.

OBJECTIVE: The aim of our study was to describe the diagnostic performances of tubomanometry (TMM) and to determine tubomanometric parameter thresholds for the diagnosis of patulous eustachian tube (PET). STUDY DESIGN: We performed a retrospective, monocentric study, including patients treated for PET vs control group. SETTING: This study was performed at the Otolaryngology Department of a tertiary-care hospital in the south of France. METHODS: We collected epidemiologic and clinical data, as well as adjusted opening latency index ("R"-index), rhinopharyngeal pressure threshold of tubal opening (Po), and velar contraction index (IVC) on TMM. Receiver operating characteristic (ROC) curves were used for determination of R index and Po thresholds. RESULTS: Twenty-one patients (26 patulous ears) and 14 controls (24 normal ears) were included. The R index values and Po values were significantly lower in the PET group vs controls (0.46 vs 0.80, respectively; P < .05 for R index and 13.89 vs 26.42 mbar, respectively; P < .05 for Po). No significant difference was reported between the 2 groups on IVC measurement (P = .784). After ROC curve analysis, R index was the most discriminating factor to classify PET patients with 89% specificity and 76% sensitivity with a threshold ≤0.6. Po value ≤10 mbar could support this diagnosis with more than 83% specificity. CONCLUSION: TMM is a reliable noninvasive method for positive diagnosis of PET. TMM could provide an accurate positive PET diagnosis and an objective evaluation for PET management.

Navigation strategies in patients with vestibular loss tested in a virtual reality T-maze.

During navigation, humans mainly rely on egocentric and allocentric spatial strategies, two different frames of reference working together to build a coherent representation of the environment. Spatial memory deficits during navigation have been repeatedly reported in patients with vestibular disorders. However, little is known about how vestibular disorders can change the use of spatial navigation strategies. Here, we used a new reverse T-maze paradigm in virtual reality to explore whether vestibular loss specifically modifies the use of egocentric or allocentric spatial strategies in patients with unilateral (n = 23) and bilateral (n = 23) vestibular loss compared to healthy volunteers (n = 23) matched for age, sex and education level. Results showed that the odds of selecting and using a specific strategy in the T-maze were significantly reduced in both unilateral and bilateral vestibular loss. An exploratory analysis suggests that only right vestibular loss decreased the odds of adopting a spatial strategy, indicating an asymmetry of vestibular functions. When considering patients who used strategies to navigate, we observed that a bilateral vestibular loss reduced the odds to use an allocentric strategy, whereas a unilateral vestibular loss decreased the odds to use an egocentric strategy. Age was significantly associated with an overall lower chance to adopt a navigation strategy and, more specifically, with a decrease in the odds of using an allocentric strategy. We did not observe any sex difference in the ability to select and use a specific navigation strategy. Findings are discussed in light of previous studies on visuo-spatial abilities and studies of vestibulo-hippocampal interactions in peripheral vestibular disorders. We discuss the potential impact of the history of the disease (chronic stage in patients with a bilateral vestibulopathy vs. subacute stage in patients with a unilateral vestibular loss), of hearing impairment and non-specific attentional deficits in patients with vestibular disorders.

Quantitative biomarkers allow the diagnosis of head and neck paraganglioma on multiparametric MRI.

PURPOSE: The aim of this study is to identify quantitative MR biomarkers in head and neck paragangliomas. METHODS: The study was approved by an institutional review board. A retrospective review of patients with head and neck paragangliomas (HNPGL) evaluated by time-resolved MRA sequences between 2009 and 2019 was performed. A control group investigated during the same period was analyzed, including nerve sheath tumors and metastatic lymph nodes from squamous cell carcinomas or undifferentiated nasopharyngeal cancer (UCNT). A gold standard was obtained for all cases. Semi-quantitative parameters of enhancement were extracted from time-intensity curves on time-resolved MRA sequences and diffusion weighted imaging/DWI was assessed for each lesion. RESULTS: Sixty head and neck paragangliomas (HNPGLs) were included from 50 patients. The control group consisted of 30 parapharyngeal space lesions (27 patients), which included nerve sheath tumors (n = 12) and metastatic lymph nodes (n = 18) from squamous cell carcinomas or UCNT. PGLs showed a shorter time-to-peak value compared to other groups, measured at 25.0 +/- 29 sec. The wash-in and wash-out ratios were also significantly higher for PGLs, respectively measured at 5.34 ± 2.99 (p < 0,001) and 1.24 ± 0.80 (p < 0.001). On DWI sequences, the mean ADC value for PGLs (1.17 ± 0.19 10^-3 mm2/s) was significantly different than the other tumor groups (p < 0.001). HNPGLs were clearly distinguishable from other tumors on classification with regression tree based on TTP and ADC values. These distinct group features were also consistent on principal component analysis. CONCLUSION: Our study identifies a multiparametric signature for disease subtyping, providing a strong impetus for switching from qualitative to quantitative analysis of deep soft-tissue tumors of the neck.

Representation of Body Orientation in Vestibular-Defective Patients Before and After Unilateral Vestibular Loss.

Introduction: The unilateral vestibular syndrome results in postural, oculomotor, perceptive, and cognitive symptoms. This study was designed to investigate the role of vestibular signals in body orientation representation, which remains poorly considered in vestibular patients. Methods: The subjective straight ahead (SSA) was investigated using a method disentangling translation and rotation components of error. Participants were required to align a rod with their body midline in the horizontal plane. Patients with right vestibular neurotomy (RVN; n =8) or left vestibular neurotomy (LVN; n = 13) or vestibular schwannoma resection were compared with 12 healthy controls. Patients were tested the day before surgery and during the recovery period, 7 days and 2 months after the surgery. Results: Before and after unilateral vestibular neurotomy, i.e., in the chronic phases, patients showed a rightward translation bias of their SSA, without rotation bias, whatever the side of the vestibular loss. However, the data show that the lower the translation error before neurotomy, the greater its increase 2 months after a total unilateral vestibular loss, therefore leading to a rightward translation of similar amplitude in the two groups of patients. In the early phase after surgery, SSA moved toward the operated side both in translation and in rotation, as typically found for biases occurring after unilateral vestibular loss, such as the subjective visual vertical (SVV) bias. Discussion and Conclusion: This study gives the first description of the immediate consequences and of the recovery time course of body orientation representation after a complete unilateral vestibular loss. The overall evolution differed according to the side of the lesion with more extensive changes over time before and after left vestibular loss. It is noteworthy that representational disturbances of self-orientation were highly unusual in the chronic stage after vestibular loss and similar to those reported after hemispheric lesions causing spatial neglect, while classical ipsilesional biases were reported in the acute stage. This study strongly supports the notion that the vestibular system plays a major role in body representation processes and more broadly in spatial cognition. From a clinical point of view, SSA appeared to be a reliable indicator for the presence of a vestibular disorder.