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.

Malignant Aspergillus flavus Otitis Externa with Jugular Thrombosis.

We report a case of malignant otitis externa with jugular vein thrombosis caused by Aspergillus flavus. Magnetic resonance imaging revealed an unusual ink smudge pattern deep in a cervical abscess. The pattern was consistent with mycetoma and may be important for diagnosing these life-threatening infections.

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.

Prospective comparison of (68)Ga-DOTATATE and (18)F-FDOPA PET/CT in patients with various pheochromocytomas and paragangliomas with emphasis on sporadic cases.

PURPOSE: Pheochromocytomas/paragangliomas (PHEOs/PGLs) overexpress somatostatin receptors and recent studies have already shown excellent results in the localization of these tumors using (68)Ga-labeled somatostatin analogs ((68)Ga-DOTA-SSA), especially in patients with germline succinate dehydrogenase subunit B gene (SDHB) mutations and head and neck PGLs (HNPGLs). The value of (68)Ga-DOTA-SSA has to be established in sporadic cases, including PHEOs. Thus, the aim of this study was to compare (68)Ga-DOTATATE PET/CT, (18)F-FDOPA PET/CT, and conventional imaging in patients with various PHEOs/PGLs with a special emphasis on sporadic cases, including those located in the adrenal gland. DESIGN: (68)Ga-DOTATATE, (18)F-FDOPA PET/CT, and conventional imaging (contrast-enhanced CT and MRI with MR angiography sequences) were prospectively performed in 30 patients (8 with SDHD mutations, 1 with a MAX mutation and 21 sporadic cases) with PHEO/PGL at initial diagnosis or relapse. RESULTS: The patient-based sensitivities were 93 % (28/30), 97 % (29/30), and 93 % (28/30) for (68)Ga-DOTATATE PET/CT, (18)F-FDOPA PET/CT, and conventional imaging, respectively. The lesion-based sensitivities were 93 % (43/46), 89 % (41/46), and 76 % (35/46) for (68)Ga-DOTATATE PET/CT, (18)F-FDOPA PET/CT, and conventional imaging respectively (p = 0.042). (68)Ga-DOTATATE PET/CT detected a higher number of HNPGLs (30/30) than (18)F-FDOPA PET/CT (26/30; p = 0.112) and conventional imaging (24/30; p = 0.024). (68)Ga-DOTATATE PET/CT missed two PHEOs of a few millimeters in size and a large recurrent PHEO. One lesion was considered false-positive on (68)Ga-DOTATATE PET/CT and corresponded to a typical focal lesion of fibrous dysplasia on MRI. Among the 11 lesions missed by conventional imaging, 7 were detected by conventional imaging with knowledge of the PET results (4 HNPGLs, 2 LNs, and 1 recurrent PHEO). CONCLUSION: (68)Ga-DOTATATE PET/CT is the most sensitive tool in the detection of HNPGLs, especially SDHD-related tumors, which may be very small and fail to concentrate sufficient (18)F-FDOPA. The present study further expands the use of (68)Ga-DOTATATE for all patients with HNPGLs, regardless of their genotype. (68)Ga-DOTATATE PET/CT may be inferior to (18)F-FDOPA PET/CT in the detection PHEOs.

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.

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.

Critical analysis of recurrences of esthesioneuroblastomas: can we prevent them?

Esthesioneuroblastoma (ENB) involving the anterior skull base is a rare malignant tumour derived from the olfactory epithelium. The gold standard of surgical treatment is currently craniofacial resection (CFR), which allows efficient removal of the tumour but entails significant morbidity. To reduce morbidity combined with good visualization of tumour limits removal, endonasal endoscopy resection (EER) has developed. The objective of this work was (1) to describe the EER surgical procedure, the morbidity, and the limitations of this endoscopic approach as compared with CFR, (2) analyse recurrences to define risk factors of recurrences and (3) to discuss a therapeutic decision algorithm. Retrospective series of 18 patients with ENB endoscopically treated in a university tertiary referral centre over 13 years. Fifteen of those underwent radiotherapy. Epidemiological data, clinical and imaging findings, histology, treatment modalities and outcome of patients were studied. Mean follow-up was 31 months. Morbidity was mainly related to radiotherapy. Three recurrences were detected: one bone and one sylvian metastasis, and a local recurrence in a patient not irradiated. One recurrence spread through leptomeningeal propagation. Dural extension and frontal invasion were significantly associated with recurrences (p = 0.001 and p = 0.019, respectively). Patients with dural extension or frontal invasion should receive aggressive treatment. With a low rate of perioperative morbidity and efficient local control, EER seems to be a promising approach for selected cases of ENB.

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.

Sunnybrook Facial Grading System: Intra-rater and Inter-rater Variabilities.

OBJECTIVES: Evaluate intra-rater and inter-rater variabilities of the Sunnybrook Facial Grading System (SFGS) and explore potential factors of variability. STUDY DESIGN: Prospective test of hypothesis. SETTING: University tertiary referral center. PARTICIPANTS/METHODS: Facial video recordings of 20 patients with variable degrees of peripheral facial palsy (PFP) were anonymized then presented to 31 independents raters in 2 trials. The raters were senior and junior professionals involved in the management of PFP: ENT specialists, physiotherapists, and speech therapists. The SFGS was used for grading paralysis. MAIN OUTCOME MEASURE: Intra-rater and inter-rater variabilities were estimated by intraclass correlation coefficient (ICC [95% confidence interval]) for the composite score and the three subscores of the SFGS. Factors of variability studied were: rater professions and rater experience (senior vs junior). RESULTS: For the total population, the intra-rater ICC was 0.915[0.900-0.929] for the composite score considered to represent almost perfect repeatability. Repeatability was important for symmetry at rest (0.694[0.646-0.737]), almost perfect for voluntary movements (0.903[0.886-0.918]), and important to almost perfect for synkinesis (0.810[0.778-0.838]). The inter-rater ICC for the composite score was 0.847[0.755-0.923] indicating important to almost perfect agreement between all raters. Agreement between raters was important to almost perfect for voluntary movements (0.839[0.746-0.919]), but moderate to important for symmetry at rest (0.553[0.408-0.730]) and weak to important for synkinesis (0.476[0.333-0.666]). Some variability was found between raters groups; however, repeatability and agreement were good for all raters. CONCLUSIONS: The SFGS is a reproducible scale. It can be used with good reproducibility by both novices and experts, and by all professionals involved in the management of PFP.

Facial Nerve Canal Paraganglioma.

We report the case of a 72-year-old woman presenting with a progressive left peripheral facial paralysis and a facial canal mass extending through the stylomastoid foramen along the posterior edge of the parotid gland. On MRI, the early and intense enhancement was highly suggestive of paraganglioma but could not rule out a nonossifying hemangioma. Laboratory analysis showed normal plasma metanephrines. On F-FDOPA PET/CT, the mass exhibited a typical paraganglioma feature with a marked tumor uptake. Our case demonstrates that F-FDOPA plays a vital role in this rare entity and can avoid any further confirmatory invasive procedure.

The Effects of Hypoxia on Middle Ear Pressure Regulation.

Background: Middle ear (ME) pressure regulation has been suggested as a physiological mechanism that maintains pressure equilibrium between the ME and the ambient environment. This mechanism would be based on a complex sensorineural reflex loop composed of mechanoreceptors, an integrative center, and efferent neural pathways. Our aim was to demonstrate that hypoxic conditions, which would inhibit mechanoreceptors in general, similarly participate in the inhibition of the opening of the Eustachian tube (ET), and thus, to suggest that such receptors are involved in the overall regulation of ME pressure. Materials and Methods: Among 14 healthy volunteers, tubomanometry was performed in normoxia followed by hypoxia, and 3 parameters were evaluated for each ear under each condition, allowing the evaluation of the reactivity of the system: ET opening latency index (R), the Index of Velum Contraction (IVC), and the latency of pressure instauration (C2-C1). Results: Hypoxia induced a significant increase in the opening latency index of ET opening, without deleterious effects on the quality (IVC) and latency (C2-C1) of soft palate contraction. Conclusions: Our study supports the theory of a sensorineural reflex loop and provides evidence for the existence of mechanoreceptors, whose function is modified by changes in oxygen partial pressure, able to collect information on pressure variations between the ME and the external environment.

Incidental Effect of Long-Term Tacrolimus Treatment on Sporadic Vestibular Schwannoma Volume Shrinkage and Clinical Improvement.

OBJECTIVE: We describe the effect of long-term tacrolimus delivery on sporadic vestibular schwannoma (VS). PATIENT: A 48-year-old woman who was diagnosed a right VS. INTERVENTION: Long-term tacrolimus delivery following liver transplant. MAIN OUTCOME MEASURES: Clinical examination, audiometric test, and gadolinium-contrasted magnetic resonance imaging. RESULTS: During the reported follow-up period, the patient felt hearing improvement especially in noisy environment. This was consistent with a clear audiometric improvement. Over a 26 months follow-up period, we noticed a 50% volume regression and a 40% decrease in the intensity of enhancement of the tumor after gadolinium injection. CONCLUSION: Tacrolimus, an immunosuppressant used to prevent rejection in organ transplant, could lead to VS volume shrinkage and hearing improvement. Tacrolimus could be an interesting new therapeutic weapon, especially for VS in Neurofibromatosis type 2.

Syngeneic Transplantation of Rat Olfactory Stem Cells in a Vein Conduit Improves Facial Movements and Reduces Synkinesis after Facial Nerve Injury.

BACKGROUND: Posttraumatic facial paralysis is a disabling condition. Current surgical management by faciofacial nerve suture provides limited recovery. To improve the outcome, the authors evaluated an add-on strategy based on a syngeneic transplantation of nasal olfactory stem cells in a rat model of facial nerve injury. The main readouts of the study were the recording of whisking function and buccal synkinesis. METHODS: Sixty rats were allocated to three groups. Animals with a 2-mm facial nerve loss were repaired with a femoral vein, filled or not with olfactory stem cells. These two groups were compared to similarly injured rats but with a faciofacial nerve suture. Olfactory stem cells were purified from rat olfactory mucosa. Three months after surgery, facial motor performance was evaluated using video-based motion analysis and electromyography. Synkinesis was assessed by electromyography, using measure of buccal involuntary movements during blink reflex, and double retrograde labeling of regenerating motoneurons. RESULTS: The authors' study reveals that olfactory stem cell transplantation induces functional recovery in comparison to nontransplanted and faciofacial nerve suture groups. They significantly increase (1) maximal amplitude of vibrissae protraction and retraction cycles and (2) angular velocity during protraction of vibrissae. They also reduce buccal synkinesis, according to the two techniques used. However, olfactory stem cell transplantation did not improve axonal regrowth of the facial nerve, 3 months after surgery. CONCLUSIONS: The authors show here that the adjuvant strategy of syngeneic transplantation of olfactory stem cells improves functional recovery. These promising results open the way for a phase I clinical trial based on the autologous engraftment of olfactory stem cells in patients with a facial nerve paralysis.

Predictive Factors of Early Postoperative and Long-Term Facial Nerve Function After Large Vestibular Schwannoma Surgery.

OBJECTIVE: The preservation of acceptable facial nerve (FN) function after surgery is the key concern for most patients with vestibular schwannomas (VS). To assess predictive factors of early postoperative and long-term FN function in patients harboring large VS operated with a FN-sparing technique. METHODS: Single-center retrospective cohort study with 169 consecutive large VS operated on between January 2003 and May 2015. Clinical, radiologic, and intraoperative factors were assessed according to FN function. RESULTS: At last follow-up examination, among the 145 patients without preoperative FN palsy, FN function was good (House-Brackmann [HB] grades I or II) in 84% and moderate (HB grade III) in 15% of patients. Only 1 patient presented with poor HB grade IV function. Multivariate logistic regression model showed the mean preoperative VS extrameatal diameter as being an independent predictor of an unfavorable initial FN outcome (odds ratio [OR], 1.062; P = 0.038). Surgical anatomic preservation of the cochlear nerve was associated with better FN outcomes (OR, 0.237; P = 0.012). A history of previous surgery seemed to be related to long-term impaired FN function (OR, 71.405; P = 0.042), as well as early postoperative FN function (OR, 19.068; P = 0.000). No correlation was found between a history of previous Gamma Knife surgery treatment (P = 0.225) or the extent of resection (P = 0.438) and impaired FN outcomes. History of previous surgery was identified as an unfavorable predictive recovery factor of impaired postoperative FN function (P = 0.034). CONCLUSIONS: As long as the extent of resection or additional Gamma Knife surgery have not been identified as predictive risk factors of postoperative FN palsy, we suggest that optimal resection is the main option for patients harboring large VS.

Unilateral vestibular deafferentation impairs embodied spatial cognition.

A growing number of studies indicate that cognitive complaints are common in patients with peripheral vestibular disorders. A better understanding of how vestibular disorders influence cognition in these patients requires a clear delineation of the cognitive domains affected by vestibular disorders. Here, we compared the consequences of left and right vestibular neurectomy on third-person perspective taking-a visuo-spatial task requiring mainly own-body mental imagery, and on 3D objects mental rotation imagery-requiring object-based mental imagery, but no perspective taking. Patients tested 1 week after a unilateral vestibular neurectomy and a group of age- and gender-matched healthy participants played a virtual ball-tossing game from their own first-person perspective (1PP) and from the perspective of a distant avatar (third-person perspective, 3PP). Results showed larger response times in the patients with respect to their controls for the 3PP taking task, but not for the 1PP task and the 3D objects mental imagery. In addition, we found that only patients with left vestibular neurectomy presented altered 3PP taking abilities when compared to their controls. This study suggests that unilateral vestibular loss affects mainly own-body mental transformation and that only left vestibular loss seems to impair this cognitive process. Our study also brings further evidence that vestibular signals contribute to the sensorimotor bases of social cognition and strengthens the connections between the so far distinct fields of social neuroscience and human vestibular physiology.

Tumor multifocality with vagus nerve involvement as a phenotypic marker of SDHD mutation in patients with head and neck paragangliomas: A 18 F-FDOPA PET/CT study.

BACKGROUND: 18 F-FDOPA PET/CT was proved to be a highly sensitive imaging method for detecting head and neck paraganglioma (HNPGL). The primary aim of the study was to evaluate the relationship between tumor characteristics and the SDHx-mutational status in a large series of patients with HNPGL evaluated by 18 F-FDOPA PET/CT. METHODS: A total of 104 patients with HNPGL (65 sporadic/39 SDHx-mutated) were included. RESULTS: In comparison to SDHB/SDC/SDHx-negative cases, patients with SDHD were younger at diagnosis and had a higher rate of multifocal, vagal, and carotid paraganglioma. In patients with SDHD, vagal paraganglia represented the primary site of tumor origin. Multicentric involvement of the vagus nerve alone or in association with other locations was found to be a typical feature of SDHD cases compared to other cases (odds ratio = 59.4). CONCLUSION: The present study shows that tumor multifocality within the vagus nerve is a phenotypic marker of SDHD mutation. This information is essential in the choice of the therapeutic strategy.