Trigeminal Function Research Articles

Neurotrophic Keratitis: A Review

Impairment in trigeminal nerve function causes a loss of corneal sensation and can lead to neurotrophic keratitis (NK). This gradual deterioration in the surface integrity of the cornea predisposes to the development of ulcers and may even progress to perforation, posing a risk for profound vision loss. Many common ophthalmic and systemic conditions, such as herpetic infections, ocular surgeries, neurosurgical procedures, multiple sclerosis and diabetes, can elicit NK by injuring the trigeminal nerve. Disease progression can occur rapidly and without symptoms, therefore, detecting NK early is critical. Management aims to halt continuing corneal damage and promote epithelial cell healing and nerve fibre regeneration. Novel treatment options show promise in restoring corneal sensitivity by re-establishing innervation, targeting the fundamental source of NK.

Rhinology in review: from COVID-19 to biologicals

We look back at the end of what soon will be seen as an historic year, from COVID-19 to real-world introduction of biologicals influencing the life of our patients. This review describes the important findings in Rhinology over the past year. A large body of evidence now demonstrates loss of sense of smell to be one of the most common symptoms of COVID-19 infection; a meta-analysis of 3563 patients found the mean prevalence of self-reported loss to be 47%. A number of studies have now shown long-term reduced loss of smell and parosmia. Given the high numbers of people affected by COVID-19, even with the best reported recovery rates, a significant number worldwide will be left with severe olfactory dysfunction. The most prevalent causes for olfactory dysfunction, besides COVID-19 and upper respiratory tract infections in general, are trauma and CRSwNP. For these CRSwNP patients a bright future seems to be starting with the development of treatment with biologics. This year the Nobel prize in Medicine 2021 was awarded jointly to David Julius and Ardem Patapoutian for their discoveries of receptors for temperature and touch which has greatly enhanced our understanding of nasal hyperreactivity and understanding of intranasal trigeminal function. Finally, a new definition of chronic rhinitis has been proposed in the last year and we have seen many papers emphasizing the importance of endotyping patients in chronic rhinitis and rhinosinusitis in order to optimise treatment effect.

Peroral Trigeminal Rhizotomy Using a Novel 3-Dimensional Printed Patient-Specific Guidance Tool.

Ganglion Gasseri rhizotomy is a viable therapeutic option for trigeminal pain (TP). For this neurosurgical procedure, different potential operative and technical nuances exist. To evaluate a novel peroral trigeminal rhizotomy method and 3-dimensional printed patient-specific guidance tool (3D-PSGT) with respect to their applicability and safety. Between March 2018 and February 2021, 20 peroral balloon compression rhizotomy procedures with a 3D-PSGT were performed in 18 consecutive TP patients (13 female, mean age 58 yr). We registered the procedure duration, side effects, complications, and trigeminal function. The therapeutic effect was gauged from reduction of TP and use of analgesics. All catheter insertions and rhizotomy procedures were successful at the first attempt. Apart from fluoroscopy, no auxiliary material was necessary. The average length of surgery was 19 min (range, 11-27 min). In total, 8 patients indicated complete analgesia and 6 patients pain relief; in 4 patients, persistence of TP was observed during follow-up examinations of up to 20 mo. In total, 6 patients reported of new mild to moderate facial hypesthesia affecting the trigeminal branches V2, V3, or V1-3. No masticatory musculature or corneal affections and device-related complications occurred. The peroral 3D-PSGT trigeminal rhizotomy is straightforward for the neurosurgeon. This operative approach allows for rapid, safe, and simple foramen ovale cannulation in TP patients and reduces the use of additional equipment, radiation exposure, and procedure time.

Outcome and Toxicity of Proton Therapy for Vestibular Schwannoma: A Cohort Study.

To assess the efficacy and toxicity of proton radiotherapy in vestibular schwannoma. Retrospective chart review and volumetric MRI-analyses. Tertiary referral center. Vestibular schwannoma patients treated with protons between 2003 and 2018. Proton radiotherapy. Tumor control was defined as not requiring salvage treatment. Progressive hearing loss was defined as a decrease in maximum speech discrimination score below the 95% critical difference in reference to the pretreatment score. Hearing assessment includes contralateral hearing and duration of follow-up. Dizziness and/or unsteadiness and facial and trigeminal nerve function were scored. Patients who had surgery prior to proton radiotherapy were separately assessed. Of 221 included patients, 136 received single fraction and 85 fractionated proton radiotherapy. Actuarial 5-year local control rate was 96% (95% CI 90-98%). The median radiological follow-up was 4.5 years. Progressive postirradiation speech discrimination score loss occurred in 42% of patients with audiometric follow-up within a year. Facial paresis was found in 5% (usually mild), severe dizziness in 5%, and trigeminal neuralgia in 5% of patients receiving protons as primary treatment. Proton radiotherapy achieves high tumor control with modest side effects aside from hearing loss in vestibular schwannoma patients. Limited and heterogeneous outcome reporting hamper comparisons to the literature. Potential sequelae of radiation therapy impacting vestibular function, cognitive function, and quality of life warrant further evaluation. Subgroups that benefit most from proton radiotherapy should be identified to optimize allocation and counterbalance its costs.

Neurological susceptibility to environmental exposures: pathophysiological mechanisms in neurodegeneration and multiple chemical sensitivity.

The World Health Organization lists air pollution as one of the top five risks for developing chronic non-communicable disease, joining tobacco use, harmful use of alcohol, unhealthy diets and physical inactivity. This review focuses on how host defense mechanisms against adverse airborne exposures relate to the probable interacting and overlapping pathophysiological features of neurodegeneration and multiple chemical sensitivity. Significant long-term airborne exposures can contribute to oxidative stress, systemic inflammation, transient receptor subfamily vanilloid 1 (TRPV1) and subfamily ankyrin 1 (TRPA1) upregulation and sensitization, with impacts on olfactory and trigeminal nerve function, and eventual loss of brain mass. The potential for neurologic dysfunction, including decreased cognition, chronic pain and central sensitization related to airborne contaminants, can be magnified by genetic polymorphisms that result in less effective detoxification. Onset of neurodegenerative disorders is subtle, with early loss of brain mass and loss of sense of smell. Onset of MCS may be gradual following long-term low dose airborne exposures, or acute following a recognizable exposure. Upregulation of chemosensitive TRPV1 and TRPA1 polymodal receptors has been observed in patients with neurodegeneration, and chemically sensitive individuals with asthma, migraine and MCS. In people with chemical sensitivity, these receptors are also sensitized, which is defined as a reduction in the threshold and an increase in the magnitude of a response to noxious stimulation. There is likely damage to the olfactory system in neurodegeneration and trigeminal nerve hypersensitivity in MCS, with different effects on olfactory processing. The associations of low vitamin D levels and protein kinase activity seen in neurodegeneration have not been studied in MCS. Table 2 presents a summary of neurodegeneration and MCS, comparing 16 distinctive genetic, pathophysiological and clinical features associated with air pollution exposures. There is significant overlap, suggesting potential comorbidity. Canadian Health Measures Survey data indicates an overlap between neurodegeneration and MCS (p < 0.05) that suggests comorbidity, but the extent of increased susceptibility to the other condition is not established. Nevertheless, the pathways to the development of these conditions likely involve TRPV1 and TRPA1 receptors, and so it is hypothesized that manifestation of neurodegeneration and/or MCS and possibly why there is divergence may be influenced by polymorphisms of these receptors, among other factors.

Patients with COVID-19-associated olfactory impairment also show impaired trigeminal function

ObjectiveNext to olfactory function, the nose can also perceive chemestetic sensations mediated by the trigeminal nerve. While olfactory dysfunction as a symptom of COVID-19 is well described, there has been little research on the limitation of other nasal sensory inputs due to SARS-CoV-2 infection. The aim of this study was to determine possible limitations of nasal chemesthesis after COVID-19 infection by a psychophysiological diagnostic tool. MethodsIn 65 patients with a PCR-confirmed, former COVID-19 disease, olfaction was tested by means of a sniffin' sticks test, tasting by taste sprays and chemesthesis with a menthol dilution series. The subjective self-assessment of the patients was recorded via a questionnaire. ResultsWe found a restriction of nasal chemesthesis and the extent correlated with the loss of smell, as well as with the values of the taste score, but not with subjective self-assessment. ConclusionNot only the ability to smell and taste, but also nasal chemesthesis is affected by COVID-19.

Smell, taste and trigeminal disorders in a 65\u2010year\u2010old population

BackgroundSmell, taste and trigeminal disorders likely have a substantial impact on human daily life. However, data regarding the prevalence of these disorders in Norway are scarce. The aim of this study was to investigate the prevalence of smell, taste, trigeminal disorders and associated factors in a 65-year-old population in Oslo, Norway.MethodsA random sample of 223 individuals (123 men, 100 women) participated in the study. Medical history was obtained, and unstimulated whole saliva (UWS) and stimulated whole saliva (SWS) were collected to determine salivary secretion rates. Sniffin`n Sticks and Taste Strips (Burghart Messtechnik GmbH, Wedel, Germany) were used for quantitative testing of olfactory and gustatory function. In addition, the participants’ self-reported perceptions of smell and taste, and burning mouth sensation were investigated.Results The results showed that 34 % of the participants had reduced smell (28 % hyposmia and 6 % anosmia) and 28 % had reduced taste perception (21 % hypogeusia and 7 % ageusia). 13 % of the partcipants had a combination of smell and taste disorders. Dysgeusia was reported by 5 % and burning mouth sensation (syndrome) by 3 % of the participants. Hyposmia, hypogeusia and ageusia were significantly more prevalent among men. Significant associations were found between taste disorders and previous history of cerebral hemorrhage and heart attack, and between burning mouth sensation and gastrointestinal disorders. Disturbances in olfactory, gustatory and trigeminal function were significantly related to medication use. Ageusia and burning mouth sensation were significantly more prevalent among smokers. Except from higher prevalence of ageusia among participants with hyposalivation with respect to SWS, no significant associations were found between salivary secretion rate and chemosensory or trigeminal disorders in the present study.ConclusionsThe present study revealed that one-third of 65-year-old individuals had impaired smell and more than one-fourth had impaired taste function. The prevalence of dysgeusia and burning mouth sensation was very low. Reduced smell and taste perception were more common among men than women. Furthermore, some diseases and medications were associated with chemosensory and trigeminal disorders. Ageusia was associated with SWS hyposalivation.

Blink reflex monitoring in microvascular decompression for trigeminal neuralgia

ABSTRACT Aim: To determine the value of the blink reflex in evaluating trigeminal sensory function during microvascular decompression for trigeminal neuralgia. Methods: The blink reflex (BR) in 103 patients with primary typical trigeminal neuralgia treated by microvascular decompression (MVD) was tested pre- and intraoperatively. The changes in BR were recorded. All patients underwent general anesthesia with intravenous propofol and fentanyl. Surgical efficacy and complications were evaluated after surgery. The relationship between intraoperative changes in the BR and postoperative trigeminal sensory function was analyzed. Results: The BR was elicited in all patients before surgery, and no significant difference was found between the affected side and the contralateral side. In 93 of the 103 cases, the BR was successfully elicited during MVD surgery. Therefore, the recordability of the BR was 90.29%. R1 latency on the affected side and the contralateral side were 11.62 ± 4.96 ms and 11.66 ± 4.37 ms, respectively. During MVD surgery, R1 of the BR disappeared on the affected side in 7 cases and remained in 86 cases. After the operation, 98 of the 103 patients had immediate and complete remission of trigeminal neuralgia symptoms, and 5 cases had partial remission. The 7 patients whose R1 disappeared during the surgery all experienced facial numbness postoperatively. Of the 86 patients whose R1 remained, only 2 patients had postoperative facial numbness. Of the 10 patients whose R1 was not recordable during the operation, one complained of postoperative facial numbness. No patients had complications such as facial paralysis, cerebrospinal fluid leakage, and death. Conclusions: Conclusion: The blink reflex may allow monitoring of trigeminal sensory function during microvascular decompression under general anesthesia.

Petrosal Approach With Preservation of the Superior Petrosal Sinus (the Graceful Petrosal) for Resection of Giant Trigeminal Schwannoma: 2-Dimensional Operative Video

Trigeminal schwannomas are benign tumors amendable to curative surgical resection.1 Excellent outcomes, with preservation and improvement of cranial nerve function, including trigeminal nerve function, have been reported with microsurgical resection through skull base approaches.2 Dumbell shaped tumors, involving the middle and posterior fossa, are more challenging.3 They are resected via a middle cranial fossa approach with the expanded Meckel cave providing access to the posterior fossa. However, tumors with a large caudal extension below the internal auditory meatus typically cannot be adequately accessed with this approach and the posterior petrosal approach is utilized.2 Specific venous anatomy might deter from cutting the tentorium. This article describes the surgical resection of a trigeminal schwannoma with a large posterior fossa component through a petrosal approach without cutting the tentorium.4 The patient is a 34-yr-old man who presented with headaches and gait disturbance. Neurological exam revealed hypoesthesia and hypoalgesia in the left V1 and V2 distributions. Magnetic resonance imaging (MRI) revealed a large dumbbell-shaped schwannoma causing brainstem compression. Magnetic resonance venography (MRV) demonstrated temporal lobe venous drainage into the superior petrosal sinus and tentorium proximal to the transverse sigmoid junction. A single temporal-suboccipital bone flap and a retro-labrynthine mastoidectomy were performed. The petrous apex was drilled and Meckle's cave opened. The presigmoid dura was opened and extended toward the petrous apex region beneath the tentorium. This provided access to and safe resection of the tumor. A gross total tumor resection was achieved. The patient remained stable neurologically and was without tumor recurrence at 3 yr postoperatively. The patient had consented to the procedure. Figures in video at 4:06 from Jafez et al, Preservation of the superior petrosal sinus during the petrosal approach, J Neurosurg. 2011;114(5):1294-1298, with permission from JNSPG.

Trigeminal impairment in treatment-refractory chronic nasal obstruction.

Patients with anatomically unexplained, chronic nasal obstruction (CNO) that is refractory to medical treatment pose a challenge for clinicians. A surgical solution, addressing mechanical obstacles, is unsuited for these patients. CNO may result from disrupted airflow perception due to activation of the intranasal trigeminal system; therefore, aim of this study is to evaluate if intranasal trigeminal function of these CNO patients is decreased. In this retrospective cross-sectional study, we compared 143 CNO patients and 58 healthy volunteers, between 18 to 80 years old. We assessed nasal patency by means of rhinomanometry (RM) and measured susceptibility of intranasal trigeminal system by the trigeminal lateralization task (TLT). TLT scores were significantly lower in CNO patients compared to controls (p less than 0.001), but RM scores were not different between groups. Accordingly, TLT allowed to identify CNO patients with an accuracy of the area under the curve (AUC) of 0.78, while the value for RM was at chance (AUC=0.47). CNO patients showed normal reaction to vasoconstrictive agents with significantly lower RM values after Xylomethazoline application. Results suggest that reported nasal obstruction in CNO patients without any obvious anatomical obstacle and resistant to medical treatment may be linked to decreased perception of nasal airflow rather than physical obstruction. In this sub-set of CNO patients, trigeminal testing more adequately reflects the reported obstruction than nasal resistance assessment does. In future studies, the relation of the trigeminal status and the subjective sensation of nasal obstruction needs to be addressed with validated patient rated outcome measures (PROMs).

Chemosensory Dysfunctions Induced by COVID-19 Can Persist up to 7 Months: A Study of Over 700 Healthcare Workers.

Several studies have revealed either self-reported chemosensory alterations in large groups or objective quantified chemosensory impairments in smaller populations of patients diagnosed with COVID-19. However, due to the great variability in published results regarding COVID-19-induced chemosensory impairments and their follow-up, prognosis for chemosensory functions in patients with such complaints remains unclear. Our objective is to describe the various chemosensory alterations associated with COVID-19 and their prevalence and evolution after infection. A cross-sectional study of 704 healthcare workers with a RT–PCR-confirmed SARS-CoV-2 infection between 2020 February 28 and 2020 June 14 was conducted 3–7 months after onset of symptoms. Data were collected with an online questionnaire. Outcomes included differences in reported chemosensory self-assessment of olfactory, gustatory, and trigeminal functions across time points and Chemosensory Perception Test scores from an easy-to-use at-home self-administered chemosensory test. Among the 704 participants, 593 (84.2%) were women, the mean (SD) age was 42 (12) years, and the questionnaire was answered on average 4.8 (0.8) months after COVID-19. During COVID-19, a decrease in olfactory, gustatory, and trigeminal sensitivities was reported by 81.3%, 81.5%, and 48.0%, respectively. Three to 7 months later, reduced sensitivity was still reported by 52.0%, 41.9%, and 23.3%, respectively. Chemosensory Perception Test scores indicate that 19.5% of participants had objective olfactory impairment. These data suggest a significant proportion of COVID-19 cases have persistent chemosensory impairments at 3–7 months after their infection, but the majority of those who had completely lost their olfactory, gustatory, and trigeminal sensitivities have improved.

Outcomes of Fractionated Radiosurgery in Cystic Vestibular Schwannoma

Evaluate outcomes of fractionated SRS in predominantly cystic vestibular schwannoma. Patients undergoing fractionated Radiosurgery for VS were retrospectively reviewed. Patients with cystic tumors were considered candidates for SRS only if they did not have symptomatic or significant radiologic brainstem compression. VSs containing dominant intra-tumoral or peri-tumoral cyst(s) > 50% of the total tumor diameter by greatest linear axial CPA dimension, single or multicystic, were included for study. Pre-treatment clinical and radiographic features, including AAO-HNS hearing class, history of facial weakness, current facial and trigeminal nerve function, AAO-HNS tumor size, and intratumoral vs peritumoral cysts were captured. All Patients underwent treatment on C-Arm Linac with CBCT image guidance to a dose of 25gy/5#. Patients underwent MRI surveillance every 6 months for the first year, annually thereafter for the subsequent 2 years, and then every other year. 15 patients (12 women; median age at treatment, 53 years; range, 36-85 years) with cystic VS met inclusion criteria. The median radiologic follow-up within the cystic group was 48 months (range, 17-100 months), and the median change in tumor size was − 4.3mm. 12 tumors (80%) shrank, 2 (13%) remained stable (experienced significant cyst enlargement within 1 year after treatment, followed by spontaneous cyst shrinkage back to the original pretreatment size), and 1 patient (7%) experienced cyst enlargement of 9 mm over 21 months and underwent retrolabyrinthine subtotal tumor removal and cyst decompression enlarged. Tumor control rate in cystic group of 93%. The median radiologic follow-up in the non-cystic control group, comprising of 53 pts. was 67 months (range, 6-141 months), and the median change in size was −2.0 mm. Tumor control in the solid group was 94%. Comparing only those tumors that decreased in size showed that there was a trend toward a greater reduction within the cystic group, intratumoral being better than peri-tumoral cystic VSs (P = .05). The present study demonstrates that tumor control after fractionated SRS for dominant intratumoral cystic VS may not differ from that of noncystic VS in properly selected cases suggesting that intratumoral cysts have a different behavior compared with those with peripheral cystic components, latter may result from trapped arachnoid or a hemorrhage-related process making them, thus, more susceptible to growth despite control of the solid portion of the tumor.

Multisensory environmental sensitivity in patients with chronic tinnitus

ObjectiveThe study aimed at investigating the sensitivity to noise and chemosensory environmental stressors as well as the relation to perceived stress, depression and anxiety in subjects with chronic tinnitus as compared to subjects without tinnitus. MethodsWe included 75 subjects with chronic tinnitus and 75 age and sex-matched subjects without tinnitus. Standardized questionnaires assessing the level of distress and impairment of quality of life caused by tinnitus, perceived level of stress, anxiety and depression, environmental noise and chemosensory sensitivity were used. A subgroup of 27 subjects with chronic tinnitus and 20 age-matched subjects without tinnitus underwent testing of olfactory function with the Sniffin’ Sticks test and testing of intranasal trigeminal function using CO2 thresholds. ResultsOur data confirmed the increased environmental noise sensitivity (NSS) in patients with tinnitus. Furthermore, we observed an increased environmental chemosensory sensitivity (CSS), but no difference in measured chemosensory function. Subjects with tinnitus showed also significant higher levels of perceived stress, anxiety and depression and those symptoms partially correlated to CSS and NSS. Predictors of both NSS and CSS results were the presence / absence of tinnitus and high anxiety levels while neither stress nor depression were found as predicting variables. ConclusionsThe results suggest that chronic tinnitus is related to a multisensory environmental hypersensitivity. Anxiety seems to be a predictor of this environmental vulnerability.

Short-term results of treatment outcome and toxicities following gamma knife surgery in cerebellopontine angle tumors

Introduction: About 5% to 10% of all intracranial neoplasms are located at the cerebellopontine (CP) angle. The most common of these is the vestibular schwannoma (VS). Aims and Objectives: The primary objective was to assess treatment outcomes in CP angle tumor post-Gamma Knife radiosurgery (GKS). Secondary objectives were the assessment of dose conformity and gradient indices for target coverage and organs-at-risk sparing along with the assessment of hearing function preservation post-GKS. We also assessed facial and trigeminal nerve function and quality of life (QoL) post-GKS. Materials and Methods: This was a retrospective study carried out in a tertiary care center of North India for 2 years and 3 months. All patients were followed up for 24 months posttreatment with a minimum follow-up at least 12 months. Tumor expansion was assessed post-GKS along with hearing preservation rates, facial and trigeminal nerve function and QoL. Results: No significant relationship between age, sex, and study variables was made out. The target tumor coverage ranged from 94% to 100%, with a mean of 97.24%. The conformity index ranged from 1.17 to 1.92, and the gradient index ranged from 1.35 to 1.73. Tumor expansion occurred in 52% of the patients (13) 6 months after GKS, though the increase in size was minimal with a standard deviation of 0.59 and did not result in any clinical deterioration of patients. Positive correlation was seen between maximum tumor size and loss of hearing function. The hearing preservation rate at 12 months post-GKS is 80%. This study also showed that GKS for VS has little impact in the deterioration of the function of the trigeminal and facial nerve and the general QoL. Conclusion: The radiation changes after GKS are generally seen after 6–12 months post-GKS and about 3–5 years are required to ascertain tumor control and any meaningful change in hearing levels and other toxicities. Thus, a longer period of follow-up is needed to validate the findings of this study.

Conceptual study of Anantavata with special reference to its Trigeminal neuralgia

Trigeminal neuralgia is a chronic pain condition that affects the trigeminal nerve, which carries sensation from face to the brain. If anyone has this condition, even mild stimulation of face such as from brushing teeth or putting on makeup may trigger a jolt of excruciating pain. Trigeminal neuralgia affects women more often than men and it’s more likely to occur in people who are older than 50 years. Trigeminal neuralgia also called as Tic Douloureux, the function of trigeminal nerve is disrupted. This disorder is not fetal but can be debilitating. Due to the intensity of the pain, some individuals may avoid daily activities or social contact because they fear an impending attack. According to Ayurveda trigeminal neuralgia can be understood as Anantavata. It is explained as diseases of head involving simultaneous vitiation of all tridosha producing sever pain at unilateral side of face. The present article deals with the Ayurvedic approach to the trigeminal neuralgia as Anantavata. Ayurvedic management of trigeminal neuralgia is based on pacifying tridosha.

Patient-Reported Outcome Measures and Provocative Testing in the Workup of Empty Nose Syndrome-Advances in Diagnosis: A Systematic Review.

Background The last 5 years have seen a surge of both clinical and scientific interest in empty nose syndrome (ENS). Although ENS is still considered a controversial diagnosis plagued by a lack of standardized diagnostic criteria, ENS is increasingly becoming recognized as a legitimate, physiologic disease entity. As such, it is important for clinicians to understand the most up-to-date diagnostic tools to assess ENS, confirm the diagnosis, and create a more standardized means to counsel these complex patients. Objective Contemporary literature review to discuss diagnostic modalities in the evaluation of ENS, in order to introduce evidence-based diagnostic criteria. Methods A systematic review was conducted in PubMed and Embase (2013–2019) using the search term “empty nose syndrome” to identify peer-reviewed articles on the topic of ENS. Articles advancing contemporary methods of ENS diagnosis and testing were included. A quality assessment was conducted using The Rational Clinical Examination Levels of Evidence. Results The novel development of the Empty Nose Syndrome 6 Questionnaire (ENS6Q) offers the clinician a validated patient-reported outcome measure to supplement history and physical examination. The in-office cotton test, performed by placing an endoscopically directed cotton plug in the site of tissue loss, may help to identify patients who may benefit from turbinate augmentation. Tools such as the sinus computed tomography scan, computational fluid dynamics, and intranasal trigeminal nerve function testing currently have insufficient evidence to support routine use in the workup of ENS. Up to 66% of ENS patients present with comorbid anxiety or depression. Conclusion The ENS6Q and cotton test assist in creating a standardized approach to the evaluation of patients suspected of ENS. These instruments should be used as an adjunct, rather than the sole criteria, on which to ascertain the presumptive diagnosis. Patients suspected of ENS should be screened for comorbid psychological dysfunction.

Chemosensory decrease in different forms of olfactory dysfunction.

The aim of this study is to investigate the effect of olfactory dysfunction (OD) on the two other chemical senses, namely gustation and the intranasal trigeminal system. Taste and trigeminal function were analyzed in a retrospective cross-sectional study of 178 participants with OD (n = 78 posttraumatic, n = 42 idiopathic, n = 27 post-infectious and n = 31 chronic rhinosinusitis (CRS) OD). All patients had been investigated for OD at our smell and taste outpatient clinic. Evaluation of olfaction was performed by means of the Sniffin' Sticks test (odor threshold, odor discrimination and odor identification), whereas gustatory function was assessed with the Taste Strips test and the intranasal trigeminal sensitivity by means of the lateralization task. The degree of olfactory impairment was found to depend on the cause of OD, but not on patients' age. Patients with posttraumatic OD showed lower olfactory function than patients with idiopathic, post-infectious and CRS OD (p = 0.01). Gustatory and trigeminal sensitivity in turn depended on age rather than the cause of olfactory dysfunction. Partial correlations between olfactory, gustatory, and trigeminal scores, with age as covariate, were significant, showing a decrease of taste and trigeminal function proportional to the OD (p < 0.05). The present data suggest that the three chemical senses are closely connected for humans underlining that in case of OD the remaining chemical senses (taste, trigeminal function) tend to decrease rather than compensate as this is seen for sensory loss in other modalities. This finding has direct clinical implications and importance when dealing with smell and taste disorders.

Twelve-year results of LINAC-based radiosurgery for vestibular schwannomas.

To report long-term outcomes of 53patients with vestibular schwannomas (VS) submitted to asingle high-dose LINAC-based radiosurgery (SRS) in our institution. 48 (92%) patients were evaluable for clinical and MRI response as well as late toxicity. At amedian follow-up of 12years (range 2-16years), local control (LC), hearing capacity, trigeminal and facial nerve function, and toxicity were assessed. Hearing capacity was classified according to the Gardner-Robertson scale, where classI-II patients had "serviceable hearing." Median dose of SRS was 16.5 Gy (range 13-20Gy) and median tumor volume 1.7 cm3 (range 0.09-7.4 cm3). 35 (73%) patients were treated with SRS alone, in the remaining 13 (27%) patients, SRS was performed as salvage therapy for recurrent or progressive tumors after previous microsurgery. Before SRS, 44patients (92%) had hearing loss and 25 (52%) had "non-serviceable" hearing. Tumor extension, classified with Koos categories, was gradeI-II in 27 (56%) and gradeIII-IV in 21 (44%) cases. LC was 100% and hearing preservation in "serviceable hearing" patients was 91%. 4 (11%) patients developed incomplete and intermittent ipsilateral facial nerve palsy which regressed in amedian time of 6months. Trigeminal toxicity was registered in 11 (23%) patients, reversible in 6 (13%) and permanent in 5 (10%). Only Koos tumor gradeIII-IV significantly influenced late toxicity (p = 0.01). LC and hearing preservation after SRS were excellent. Toxicity proved acceptable. Although the median administered dose (16.5 Gy) was rather high, the only factor which significantly influenced late toxicity was Koos tumor gradeIII-IV.

Update on empty nose syndrome: disease mechanisms, diagnostic tools, and treatment strategies.

To discuss the proposed pathophysiology of empty nose syndrome (ENS), summarize and evaluate the role of validated diagnostic tools in the diagnosis of ENS, and review the medical and surgical treatment strategies for patients with ENS. Historically, ENS has been associated with a reduction in nasal turbinate size; new data suggest that impaired trigeminal nerve function may also play a role in the pathophysiology of the disease. The newly validated empty nose syndrome 6 item questionnaires and Cotton test are steps forward to standardize the diagnosis of ENS. Finally, there has been a marked increase in surgical treatment strategies to reconstitute turbinate volume with various implant materials. The diagnosis of ENS remains controversial but the last several years have seen a rejuvenation of interest in this disease entity. The validated empty nose syndrome 6 item questionnaires and Cotton test provide a standardized and objective means by which to characterize ENS. Prevention of iatrogenic ENS through avoidance of excessive turbinate reduction remains critical in preventing paradoxical nasal obstruction. Nasal humidification, patient education, and treatment of possible concomitant medical conditions (e.g., depression) constitute first lines of treatment. We support the cautious use of these screening tools as adjuncts to clinical decision-making. Although injectable implants to augment turbinate volume show promise as a therapeutic surgical technique, there is insufficient data to fully support their use at this time.

Development of a new psychophysical method to assess intranasal trigeminal chemosensory function.

The aim of this study was to develop a new psychophysical test to assess intranasal trigeminal chemosensory function. The test is similar to the Sniffin’ Sticks test, but using pens impregnated with substances preferentially activating trigeminal afferents. Our test comprises detection threshold, discrimination, identification and lateralization tasks. In a first study, we evaluated healthy controls. In a second study, we evaluated the potential usefulness of this test in patients with rhinological conditions. Study 1: 86 controls were included. Threshold, identification and lateralization performance decreased with age. Test-retest reliability was similar to that of olfactory tests. Study 2: results of the controls group were compared to those of 59 patients (14 allergic rhinitis, 11 chronic rhinosinusitis with nasal polyps (CRSwNP), 9 without nasal polyps (CRSsNP), and 25 with an olfactory disorder (OD)). Controls had 1) lower detection thresholds compared to CRSwNP, CRSsNP and OD, 2) better discrimination and identification scores compared to OD, and 3) better lateralization scores compared to CRSwNP and CRSsNP. Our test allows to identify age-related changes in trigeminal chemosensory function. Trigeminal function seems to be differently affected in different pathologies. Further studies are necessary to validate our results and evaluate the impact of olfactory co-activation on the observed results.