Glossopharyngeal Research Articles

Morphology of GNAT3-immunoreactive chemosensory cells in the nasal cavity and pharynx of the rat.

Solitary chemosensory cells and chemosensory cell clusters are distributed in the pharynx and larynx. In the present study, the morphology and reflexogenic function of solitary chemosensory cells and chemosensory cell clusters in the nasal cavity and pharynx were examined using immunofluorescence for GNAT3 and electrophysiology. In the nasal cavity, GNAT3-immunoreactive solitary chemosensory cells were widely distributed in the nasal mucosa, particularly in the cranial region near the nostrils. Solitary chemosensory cells were also observed in the nasopharynx. Solitary chemosensory cells in the nasopharyngeal cavity were barrel like or slender in shape with long lateral processes within the epithelial layer to attach surrounding ciliated epithelial cells. Chemosensory cell clusters containing GNAT3-immunoreactive cells were also detected in the pharynx. GNAT3-immunoreactive cells gathered with SNAP25-immunoreactive cells in chemosensory clusters. GNAT3-immunoreactive chemosensory cells were in close contact with a few SP- or CGRP-immunoreactive nerve endings. In the pharynx, GNAT3-immunoreactive chemosensory cells were also attached to P2X3-immunoreactive nerve endings. Physiologically, the perfusion of 10mM quinine hydrochloride (QHCl) solution induced ventilatory depression. The QHCl-induced reflex was diminished by bilateral section of the glossopharyngeal nerve, suggesting autonomic reflex were evoked by chemosensory cells in pharynx but not in nasal mucosa. The present results indicate that complex shape of nasopharyngeal solitary chemosensory cells may contribute to intercellular communication, and pharyngeal chemosensory cells may play a role in respiratory depression.

SARS-CoV-2: The Road Less Traveled-From the Respiratory Mucosa to the Brain.

Neurological manifestations have been reported in COVID-19; however, the route used by SARS-CoV-2 to enter the brain is still under debate. Recent studies have focused on the olfactory route. SARS-CoV-2 viral proteins were also detected in the glossopharyngeal and vagal nerves originating from the lower brainstem and in isolated cells of the brainstem. Our proof of concept in vivo real-time imaging study of mice using an indocyanine green dye indicated that the neurovascular component of the connective tissue of the respiratory mucosa can also provide an alternate route to the brain.

Laryngofissure in comorbid patient under ultrasound-guided regional anesthesia of the neck

BackgroundMajor neck surgery is done typically under general anesthesia (GA). The neural blocks of the neck include blocking of the cervical plexus, superior laryngeal nerve, trans-laryngeal, block of the glossopharyngeal nerve, and local anesthetic infiltration. In patients with a high risk of GA, including those with pulmonary dysfunction, and prior myocardial ischemia or infarction, regional anesthesia is mainly indicated.Case presentationWe record a case of a comorbid geriatric patient with dysphonia and left glottic mass that was diagnosed as squamous cell papilloma by transoral biopsy using curved biopsy forceps under local spray anesthesia, and after 6 months, this patient developed stridor for which tracheostomy, laryngofissure, and left cordectomy were then performed solely under neck blocks. Surgery was performed while the patient remained pain-free and stable without any morbidity throughout the operation.ConclusionsIn high-risk patients and low-resource health systems, regional anesthesia in neck surgery can be a reasonable and cheap alternate to general anesthetics.

Refractory neck pain due to Eagle syndrome.

Eagle syndrome, named after Watt W. Eagle, who described the first cases in 1937, is an uncommon syndrome (4-8/10,000 persons) resulting from the styloid process's elongation or mineralization of the stylohyoid ligament.1Badhey A. Jategaonkar A. Anglin Kovacs A.J. Kadakia S. De Deyn P.P. Ducic Y. et al.Eagle syndrome: a comprehensive review.Clin Neurol Neurosurg. 2017; 159: 34-38Crossref PubMed Scopus (54) Google Scholar The typical symptoms are throat and neck pain radiating into the ear, which can be wrongly attributed to various facial neuralgias. A 64-year-old woman had presented to the otolaryngology clinic with a slowly progressive intermittent dull pain in the upper neck of 10 years' duration. The pain was localized to the tonsillar fossa and radiated to the jaw, ear, neck, throat, and oropharynx. It was worsened by head movement and accompanied by dysphagia, a foreign body sensation, a sore throat, and voice changes. She had no history of trauma. The patient had undergone several consultations during the 10-year period, including otolaryngology, family practice, neurology, neurosurgery, psychiatry, and dentistry, with various interventions performed (ie, steroid injection in the temporomandibular joint, radiofrequency ablation, stellate ganglion block, lignocaine infusion, posterior auricular nerve block) without relief. A computed tomography angiogram demonstrated a 4-cm-long styloid process at the level of the mid-internal carotid artery (A and B). Cervical neck incision and styloidectomy were planned. We exposed the common carotid artery and cranial nerves and retracted the posterior belly of the digastric to peel the tendinous attachment around the styloid process toward the mastoid posteriorly and mandible anteriorly for easy separation. The distal end of the styloid process was found to lie close to the hypoglossal, glossopharyngeal, and vagus nerves (C). A 2.5-cm excision of the styloid process was performed. She had complete resolution of the symptoms postoperatively. She had provided written informed consent for the report of her case details and images. The styloid process normally measures 2.5 to 3 cm. However, when its length is >3 cm, the patient will become symptomatic owing to the subsequent pressure on the adjacent structures.1Badhey A. Jategaonkar A. Anglin Kovacs A.J. Kadakia S. De Deyn P.P. Ducic Y. et al.Eagle syndrome: a comprehensive review.Clin Neurol Neurosurg. 2017; 159: 34-38Crossref PubMed Scopus (54) Google Scholar Cervical neck surgery with styloidectomy is the definitive treatment. An alternative approach includes the intraoral transtonsillar route. However, this approach has been associated with high risks, including uncontrolled bleeding and cranial nerve injury because it limits visualization of the important structures.2Strauss M. Zohar Y. Laurian N. Elongated styloid process syndrome: intraoral versus external approach for styloid surgery.Laryngoscope. 1985; 95: 976-979Crossref PubMed Google Scholar

Risk and Clinical Risk Factors Associated With Late Lower Cranial Neuropathy in Long-term Oropharyngeal Squamous Cell Carcinoma Survivors

Lower cranial neuropathy (LCNP) is a rare, but permanent, late effect of radiotherapy and other cancer therapies. Lower cranial neuropathy is associated with excess cancer-related symptoms and worse swallowing-related quality of life. Few studies have investigated risk and clinical factors associated with late LCNP among patients with long-term survival of oropharyngeal squamous cell carcinoma (OPSCC survivors). To estimate the cumulative incidence of and identify clinical factors associated with late LCNP among long-term OPSCC survivors. This single-institution cohort study included disease-free adult OPSCC survivors who completed curative treatment from January 1, 2000, to December 31, 2013. Exclusion criteria consisted of baseline LCNP, recurrent head and neck cancer, treatment at other institutions, death, and a second primary, persistent, or recurrent malignant neoplasm of the head and neck less than 3 months after treatment. Median survival of OPSCC among the 2021 eligible patients was 6.8 (range, 0.3-18.4) years. Data were analyzed from October 12, 2019, to November 13, 2020. Late LCNP events were defined by neuropathy of the glossopharyngeal, vagus, and/or hypoglossal cranial nerves at least 3 months after cancer therapy. Cumulative incidence of LCNP was estimated using the Kaplan-Meier method, and multivariable Cox proportional hazards models were fit. Among the 2021 OPSCC survivors included in the analysis of this cohort study (1740 [86.1%] male; median age, 56 [range, 28-86] years), 88 (4.4%) were diagnosed with late LCNP, with median time to LCNP of 5.4 (range, 0.3-14.1) years after treatment. Cumulative incidence of LCNP was 0.024 (95% CI, 0.017-0.032) at 5 years, 0.061 (95% CI, 0.048-0.078) at 10 years, and 0.098 (95% CI, 0.075-0.128) at 15 years of follow-up. Multivariable Cox proportional hazards regression identified T4 vs T1 classification (hazard ratio [HR], 3.82; 95% CI, 1.85-7.86) and accelerated vs standard radiotherapy fractionation (HR, 2.15; 95% CI, 1.34-3.45) as independently associated with late LCNP status, after adjustment. Among the subgroup of 1986 patients with nonsurgical treatment, induction chemotherapy regimens including combined docetaxel, cisplatin, and fluorouracil (TPF) (HR, 2.51; 95% CI, 1.35-4.67) and TPF with cetuximab (HR, 5.80; 95% CI, 1.74-19.35) along with T classification and accelerated radiotherapy fractionation were associated with late LCNP status after adjustment. This single-institution cohort study found that, although rare in the population overall, cumulative risk of late LCNP progressed to 10% during the survivors' lifetime. As expected, clinical factors associated with LCNP primarily reflected greater tumor burden and treatment intensity. Further efforts are necessary to investigate risk-reduction strategies as well as surveillance and management strategies for this disabling late effect of cancer treatment.

Thermographic follow-up of postherpetic neuralgia (PHN) subsequent to Ramsay Hunt syndrome with multicranial nerve (V, VII, VIII and IX) involvement: a case report

BackgroundRamsay Hunt syndrome (RHS) is caused by a reactivation of varicella-zoster virus (VZV) infection, and it is characterized by the symptoms of facial paralysis, otalgia, auricular rash, and/or an oral lesion. Elderly patients or immunocompromised patients, deep pain at the initial visit and no prompt treatment are significant predictors of postherpetic neuralgia (PHN). When PHN occurs, especially involved cranial polyneuropathy, multiple modalities should be administered for patients with the intractable PHN. The use of thermography in the follow-up of PHN secondary to RHS with multicranial nerve involvement has not yet been described yet in the literature.Case presentationThe patient was a 78-year-old man with the chief complaint of a 3-month history of PHN secondary to RHS with polycranial nerve (V, VII, VIII, and IX) involvement. Multimodality therapy with oral gabapentin, pulsed radiofrequency (PRF) application to the Gasserian ganglion for pain in the trigeminal nerve region, linear-polarized near-infrared light irradiation for pain in the facial nerve region, and 2% lidocaine spray for pain in the glossopharyngeal nerve region was used to the treat patient, and follow-up evaluations included thermography. This comprehensive treatment obviously improved the quality of life, resulting in considerable pain relief, as indicated by a decrease in the numerical rating scale (NRS) score from 9 to 3 and a decrease in thermal imaging temperature from higher to average temperature on the ipsilateral side compared with the contralateral side. Lidocaine spray on the tonsillar branches of the glossopharyngeal nerve resulted in an improvement in odynophagia, and the NRS score decreased from 9 to 0 for glossopharyngeal neuralgia after three applications.ConclusionAlthough the use of thermography in the follow-up of RHS with multiple cranial nerve (V, VII, VIII, and IX) involvement is very rare, in this patient, thermal imaging showed the efficacy of combination therapy (oral gabapentin, 2% lidocaine sprayed, PRF application and linear-polarized near-infrared light irradiation) and that is a good option for treatment.

Psychosomatic disorders: influence of white noise on disease in patients with cervicalgia (Message 1)

Introduction . Psychosomatic disorders (PSR) develop as a result of somatization of psychogenic factors. In osteopathy, PSRs are reflected in the so-called psychoviscerosomatic disorder which is a variant of a global neurodynamic functional disorder characterized by poly-regional disorders of tissue mobility that are associated with psychoemotional overloads. In most cases of PSR, neurotization of patients is obligate due to the involvement of a number of nervous structures in the pathological process and the subsequent general decrease in the body's adaptive reserves. According to the polyvagal theory of S. Porges (1995), the vagus nerve is divided into two functionally different branches: nucl. dorsalis n. vagi and n. ambigius. Third core nucl. tractussolitarii is the endpoint of many afferent pathways through n. vagus from peripheral organs, which forms the central regulator of the vagal system. In the process of phylogenesis, the vagus nerve system became more complex due to the inclusion of the pathways of the trigeminal, facial, accessory and glossopharyngeal nerves. S. Porges distinguishes the autonomic vagus nerve associated with passive regulation of visceral functions and the social or intellectual vagus, which is responsible for the processes of attention, movement and communication. The auditory sensory system provides encoding and evaluation of acoustic stimuli that determine the ability to adapt. We suggested that by affecting the auditory system, it is possible to affect the autonomic nervous system and reduce the severity of individual symptoms of PSR. The goal of research — is to study the effect of white noise (WN) stimulation of the auditory sensory system on the manifestations of the disease in patients with cervicalgia (CA). Materials and methods . In the period from 03.2020 to 07.2020 on the basis of the «Professor Novikov'sFamily Osteopathy Clinics», an analytical one-stage (cross-sectional) study was conducted, which involved 109 patients with an established clinical diagnosis of CA, who were divided into two groups: an experimental group (76 people) exposed to WN, and a control group (33 people), in which there was no such exposure. To irritate the auditory sensory system, a WN with a frequency of 1-22,05 kHz was used. Patients of the experimental group were divided into 3 groups depending on the level of neuroticism: low (13 people), medium (49 people), high (14 people). The examination included an assessment of the level of neuroticism, biomechanical indicators that characterize the volume of movements in the cervical region, and the level of pain. The L. I. Wasserman questionnaire was used to assess the level of personal neuroticism. The volume of movements in the cervical spine in degrees was determined using an original device for determining the mobility of the cervical spine. Subjective assessment of pain was performed using the VAS scale. To obtain a quantitative assessment of the achieved result, a «B-A-analysis» method is proposed, based on the evaluation of the modules of 6-timer (by the number of analyzed indicators) vectors A (after the study) and B (before the study) and pairwise analysis of the corresponding components of these vectors. Results . Patients of the main group in subgroups with high, medium and low levels of neuroticism irritation auditory system has led to increased range of motion in the cervical spine that best identified patients with low levels of neuroticism, and minimally high. No significant changes were registered in the control group. There was no convincing difference in the dynamics of VAS indicators. Conclusion . The study showed the possibility of influencing biomechanical parameters when the auditory sensory system is irritated by WN in patients with CA, and the result differed depending on the level of neuroticism — high, medium, low. The subjective assessment of the pain syndrome in VAS case is significantly influenced by the emotional component. Thus, if the nervous system is exposed, the biomechanical parameters changes take place, and it indirectly confirms the integrity and interdependence of the neurodynamic and biomechanical components of functional disorders. The results suggest further study of the possibilities of using WN in patients with various somatic dysfunctions accompanying PSR.

R-spondin substitutes for neuronal input for taste cell regeneration in adult mice

Taste bud cells regenerate throughout life. Taste bud maintenance depends on continuous replacement of senescent taste cells with new ones generated by adult taste stem cells. More than a century ago it was shown that taste buds degenerate after their innervating nerves are transected and that they are not restored until after reinnervation by distant gustatory ganglion neurons. Thus, neuronal input, likely via neuron-supplied factors, is required for generation of differentiated taste cells and taste bud maintenance. However, the identity of such a neuron-supplied niche factor(s) remains unclear. Here, by mining a published RNA-sequencing dataset of geniculate ganglion neurons and by in situ hybridization, we demonstrate that R-spondin-2, the ligand of Lgr5 and its homologs Lgr4/6 and stem-cell-expressed E3 ligases Rnf43/Znrf3, is expressed in nodose-petrosal and geniculate ganglion neurons. Using the glossopharyngeal nerve transection model, we show that systemic delivery of R-spondin via adenovirus can promote generation of differentiated taste cells despite denervation. Thus, exogenous R-spondin can substitute for neuronal input for taste bud cell replenishment and taste bud maintenance. Using taste organoid cultures, we show that R-spondin is required for generation of differentiated taste cells and that, in the absence of R-spondin in culture medium, taste bud cells are not generated ex vivo. Thus, we propose that R-spondin-2 may be the long-sought neuronal factor that acts on taste stem cells for maintaining taste tissue homeostasis.

Innervation of human soft palate muscles.

Our objective was to determine the branching and distribution of the motor nerves supplying the human soft palate muscles. Six adult specimens of the soft palate in continuity with the pharynx, larynx, and tongue were processed with Sihler's stain, a technique that can render large specimens transparent while counterstaining their nerves. The cranial nerves were identified and dissection followed their branches as they divided into smaller divisions toward their terminations in individual muscles. The results showed that both the glossopharyngeal (IX) and vagus (X) nerves have three distinct branches, superior, middle, and inferior. Only the middle branches of each nerve contributed to the pharyngeal plexus to which the facial nerve also contributed. The pharyngeal plexus was divided into two parts, a superior innervating the palatal and neighboring muscles and an inferior innervating pharyngeal constrictors. The superior branches of the IX and X nerves contributed innervation to the palatoglossus, whereas their middle branches innervated the palatopharyngeus. The palatoglossus and palatopharyngeus muscles appeared to be composed of at least two neuromuscular compartments. The lesser palatine nerve not only supplied the palatal mucosa and palatine glandular tissue but also innervated the musculus uvulae, palatopharyngeus, and levator veli palatine. The latter muscle also received its innervation from the superior branch of X nerve. The findings would be useful for better understanding the neural control of the soft palate and for developing novel neuromodulation therapies to treat certain upper airway disorders such as obstructive sleep apnea.

Risk and Predictors of Late Lower Cranial Neuropathy in Long-term Oropharyngeal Cancer Survivors Treated with Definitive Radiotherapy: A Retrospective Cohort Study among 1,988 Survivors

Lower cranial neuropathy (LCNP) is a rare, but permanent, late effect of radiotherapy (RT) and other cancer therapies. The objective of this study was to quantify the cumulative incidence and identify clinical predictors of late LCNP. We hypothesized that 5-year incidence rate of late LCNP would approximate 5% and risk would correlate with tumor subsite and stage, RT dose, fractionation schedule, smoking status, and systemic therapy. This study included 1,988 OPC survivors (median survival: 6.85, range: 0.30-18.41 years) who received definitive RT at a single institution from 2000 to 2013. Late LCNP events defined by neuropathy of the glossopharyngeal (IX), vagus (X) and hypoglossal (XII) nerves ≥3-months after cancer therapy with normal baseline nerve function were abstracted from medical records. Cumulative incidence of LCNP was estimated using the Kaplan Meir method and multivariable Cox proportional hazard models were fit. About 4.4% (n = 87) of OPC survivors were diagnosed with late LCNP with median time to LCNP onset of 5.52 (range: 0.3-14.1) years post-treatment. Cumulative incidence of LCNP was 0.02 (95% CI: 0.02-0.03), 0.06 (95% CI: 0.05-0.08), and 0.10 (95% CI: 0.07-0.13) at 5, 10, and 15 years of follow-up, respectively. Multivariable Cox regression identified T4 vs T1 stage (HR: 3.90; 95%CI: 1.89-8.05, p<0.001) and accelerated vs standard RT fractionation (HR 2.20, 95%CI 1.37-3.53, p = 0.001) as independently associated with late LCNP status, adjusting for age, subsite, smoking, therapeutic modality, and solid food diet at baseline. Further, among all patients induction chemotherapy regimen as either TPF (docetaxel, cisplatin, and fluorouracil; HR: 2.37; 95%CI: 1.28-4.39; p = 0.006) or C-TPF (cetuximab, docetaxel, cisplatin, and fluorouracil; HR: 4.0; 95%CI: 1.22-13.15, p = 0.022) were identified in addition to T-stage (model with TPF; HR: 3.72, 95%CI: 1.81-7.65, p = <0.001; model with CTPF; HR: 3.97, 95%CI: 1.92-8.21, p = <0.001 ) and accelerated RT fractionation (model with TPF; HR: 2.56, 95%CI: 1.55-4.21, p = <0.001; model with CTPF; HR: 2.28, 95%CI: 1.41-3.68, p = 0.001) as significantly associated with late LCNP after adjustment. In our large cohort study, the risk of late LCNP progressed to exceed 10% cumulative risk over the lifetime of OPC survivors at 15 years follow-up. Our prediction model identified survivors with larger T4 tumors, those treated with more intensive treatment regimens including accelerated RT fractionation and induction TPF or CTPF as having a higher risk of late LCNP even after controlling for potential cofounders, suggesting that some LCNP risk may be modifiable. Further efforts are necessary to investigate other associations and effective risk reduction strategies for this disabling late effect experienced by growing numbers of long-term OPC survivors.

Frameless Radiosurgery for Intractable Idiopathic Glossopharyngeal Neuralgia

Glossopharyngeal neuralgia (GPN) is a rare disorder of the ninth cranial nerve characterized by severe, paroxysmal episodes of pain localized to the posterior tongue, tonsil, throat, or external ear canal. The pain is similar to that experienced with trigeminal neuralgia (TN) and can be triggered by eating, swallowing, and speaking. The pain of GPN can also be associated with hemodynamic instability and life-threatening syncopal episodes. Though traditional treatment for GPN involves medical management at first and surgery for refractory cases, these therapies are often poorly tolerated in the elderly population. Goal of this study was to evaluate the safety and efficacy of Linac based frameless stereotactic radiosurgery (SRS) for patients with intractable idiopathic glossopharyngeal neuralgia From 20011 to 2017, 7 patients (3 male and 4 female) with median age was 60 years presented with medically refractory GPN and all had a long history of pain, median duration (28-70 mo.). In 4 cases, a neurovascular conflict had been identified on MRI. Three patients had unsuccessful prior surgical procedures, including microvascular decompression (MVD) (n = 2) and balloon compression (n = 1). In 4 cases, a neurovascular conflict had been identified on MRI. For the SRS procedure, all patients underwent double reinforced mask/byte immobilization, planning bone CT, Planning MRI (T2 CISS / FIESTA). The target was located at the glossopharyngeal meatus of the jugular foramen. Treatment was delivered on C arm Linac with 6-DOF couch capabilities, 5mm stereotactic cones and intrafraction imaging to ensure submm and sub degree precision. The median dose administered to the nerve was 80 Gy (range: 80-85gy). Follow-up was planned for 3, 6, and 12 months after the procedure and annually thereafter 5 patients experienced an improvement in their pain. The median length of time from SRS to symptom improvement in this group was 7 weeks (range 2-12 months). At the first follow-up, 5 patients were pain-free (pain intensity scores of I-III, based on an adaptation of the Barrow Neurological Institute scoring system for trigeminal neuralgia), including 4 patients who were also medication-free (I). One patient had partial improvement (IV) and 1 patient had no change. The mean duration of follow-up was 46 months (range 10-50 months). No side effect was observed. No patient developed changes in vocal cord function or swallowing disorders after SRS in this study First paper reported in literature showing efficacy of non-invasive frameless radiosurgery as surgical alternative with very high short- & long-term efficacy and without permanent complications for medically refractory glossopharyngeal neuralgia.

RETCHING IN PNEUMONIA: AN UNCOMMON PRESENTATION OF A COMMON PROBLEM

SESSION TITLE: Medical Student/Resident Chest Infections Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Retching is defined as periodic, forceful, spasmodic contraction of the muscles of the diaphragm, abdomen and chest wall without the expulsion of the contents of the stomach. It often occurs as a precursor to vomiting. Here we present the case of a patient presenting with retching as his only symptom, the cause was deemed to be community acquired pneumonia. CASE PRESENTATION: A 60-year-old man with a 40-pack-year smoking history presented with 4 days of severe retching. He described this as dry heaving, the sensation of vomiting with nothing coming up. He denied any cough, fever, chest pain or vomiting. Labs were significant for a WBC of 19,700/mL, and a serum sodium of 126mEq/L. Remaining serum electrolytes were normal. Urine sodium was 24mEq/L and urine osmolality was 307mOsm/kg. CT chest showed a 7.5 x 3.6cm focal opacification in the right upper lobe (fig 1). The patient was started on Piperacillin/Tazobactam with a plan to biopsy the lesion if there was no improvement. He was given Prochlorperazine which led to immediate improvement, with complete resolution of retching by day 4. A Repeat CT done after completion of a 10 day course of antibiotics (fig 2) showed some improvement. Follow up CT at 6 months (fig 3) showed complete resolution. DISCUSSION: Retching is a prelude to vomiting and involves contraction of the diaphragm and intercostal muscles with a closed glottis to reduce intrathoracic pressure while abdominal wall muscles contract to increase intra-abdominal pressure. The lower esophageal sphincter remains closed preventing ejection of gastric contents. The physiologic pathway of the emetic reflex is not completely understood, but it involves afferent input to the brainstem centers like solitary tract nucleus and the chemoreceptor trigger zone (CTZ) via the vagus, glossopharyngeal, trigeminal and phrenic nerves. This leads to stimulation of the vomiting center. Impulse then travels to the nucleus ambiguus, dorsal motor nucleus of the vagal nerve, and the ventral respiratory group leading to the aforementioned muscular action associated with retching. In the index patient we hypothesize that the inflammatory response associated with pneumonia led to irritation of the vagus and phrenic nerves causing persistent retching. This is supported by the improvement of symptoms after administration of prochlorperazine, which works via suppression of the CTZ. Further, there was complete resolution of retching after treatment with antibiotics. The patient’s smoking history, hyponatremia due to SIADH, and the presence of a large mass raised concerns for malignancy, as such biopsy was planned if lesion did not improve after antibiotic treatment. CONCLUSIONS: Evaluation of the thorax with imaging is prudent in patients presenting with retching as inflammatory, infectious or malignant lesions can cause this symptom via stimulation of the afferent limbs of the vagus or phrenic nerves. Reference #1: Quigley EM, Hasler WL, Parkman HP. AGA technical review on nausea and vomiting. Gastroenterology. 2001;120(1):263-86. Reference #2: Nair J, Streeter KA, Turner SMF, et al. Anatomy and physiology of phrenic afferent neurons. J Neurophysiol. 2017;118(6):2975-2990 Reference #3: Babic T, Browning KN. The role of vagal neurocircuits in the regulation of nausea and vomiting. Eur J Pharmacol. 2014;722:38-47 DISCLOSURES: No relevant relationships by Muhammad Faiz, source=Web Response No relevant relationships by Jovan Gayle, source=Web Response No relevant relationships by Somshukla Ghosh, source=Web Response No relevant relationships by Moises Matos, source=Web Response No relevant relationships by Jose Urdaneta Jaimes, source=Web Response

Nerve fiber analysis of the lingual branch of the glossopharyngeal nerve in human adult subjects.

Fibers of the glossopharyngeal part of the superior constrictor muscle are connected with fibers of the transverse lingual muscle, forming a ring of muscle at the base of the tongue. This group of muscles constrict the midpharyngeal cavity during retrusive movement of the tongue. The purpose of this study is to identify the contribution of the lingual branch of the glossopharyngeal nerve to the neuro-motor control of three muscles: the glossopharyngeal part of the superior pharyngeal constrictor muscle, the palatopharyngeal and the palatoglossus muscles. Six en bloc samples (9 sides), including the tissue from the skull base to the hyoid bone were obtained from adult human cadavers. Nerve fiber of the lingual branch of the glossopharyngeal nerve (main root of the glossopharyngeal nerve) was examined by the use of a binocular stereomicroscope. We observed that, after branching to the stylopharyngeal muscle, the lingual branch of the glossopharyngeal nerve branched to the glossopharyngeal part of the superior pharyngeal constrictor muscle, the palatopharyngeal and the palatoglossus muscles before inserting into the space between the muscle layers of the superior and middle pharyngeal constrictors. These neuromuscular arrangements may suggest the presence of specialized constrictive movements of the midpharygeal cavity at the level of the base of the tongue with the retrusive movement of the tongue. The simultaneous contraction of the palatopharyngeal and palatoglossus muscles on the pharyngeal stage of deglutition may aid in the passage of bolus from the oral cavity to the midpharyngeal cavity by increasing pharyngeal pressure.

Anatomical study of a surgical approach through the neck to the jugular foramen under endoscopy.

To investigate the feasibility of an endoscopic surgical approach through the neck to the jugular foramen, to determine the relevant techniques and extent of exposure, and to provide a new surgical approach with minimal trauma. Nine cadaveric head specimens with attached necks were fixed with 10% formalin solution. Two of the heads were fixed and injected withcolored silicone rubber. Through the dissection of these cadaver head and neck specimens, we designed a surgical approach from the neck to the jugular foramen area with the use of a neuroendoscope and performed simulated surgery to determine which anatomical structures were encountered in the approach. The posterior aspect of the internal jugular vein is adjacent to the rectus capitis lateralis. The internal carotid artery is anteromedial to the internal jugular vein, with the glossopharyngeal nerve, accessory nerve, vagus nerve and hypoglossal nerve in between. Removal of the rectus capitis lateralis can reveal the jugular process, and exposing the space between the superior oblique muscle and the jugular process can reveal the atlanto-occipital joint. Drilling through the occipital condyle can facilitate entrance into the skull, expose the flank of the medulla oblongata, and reveal the medullary olive and accessory nerve, vagus nerve, hypoglossal nerve, vertebral artery and posterior inferior cerebellar artery. Removing the jugular vein and completely opening the posterior wall of the jugular foramen can expose the inferior wall of the jugular bulb and the inferior wall of the sigmoid sinus. Drilling through the styloid process, which is lateral to the internal jugular vein, can expose the lateral area and upper wall of the jugular bulb and cranial nerves (CN) IX-XII; and near the top of the jugular bulb, the tympanic cavity and the external auditory canal can be easily opened. Endoscopic surgical access from the neck to the jugular foramen is feasible. This surgical approach can simultaneously remove intracranial and extracranial tumors and can also be used to remove tumors in the ventral region of the occipital foramen and the hypoglossal canal. Furthermore, this approach is advantageous in that minimal trauma is inflicted. With judicious patient selection, this approach may have significant advantages and may be used as a primary or secondary surgical approach in the future. Nonetheless, this approach is still in development in a laboratory setting, and further research and improvements are needed before facing more complicated situations in clinical practice.

Advanced Robotic Surgery of the Parapharyngeal Space: Transoral Robotic Styloidectomy in Eagle Syndrome.

Eagle syndrome (ES) is characterized by symptomatic elongation of the styloid process or ossification of the stylohyoid ligament causing irritation and inflammation of the trigeminal, facial, glossopharyngeal, and vagus nerves. The use of robotic surgery has been accepted as a first-line treatment for some head and neck squamous cell carcinomas but not for styloidectomy. The aim of this article is to document our experience with a transoral robotic approach to treat ES and to present the outcomes of 6 patients.The author present the transoral robotic surgery as a successful alternative for the surgical management of ES. Our experience with this approach has been excellent, granting an optimal vision of the surgical field with the consequent safe manipulation of the instruments avoiding injuries to healthy tissue.

Study of the Anatomical Features of the Offending Arteries Involved in Glossopharyngeal Neuralgia.

The anatomic features of the posterior inferior cerebellar arteries (PICAs) and the anterior inferior cerebellar arteries (AICAs) as offending arteries involved in glossopharyngeal neuralgia (GPN) are important to dictate the best surgical approach. To study and classify the anatomic features of the offending arteries. All clinical data and surgical videos from 18 GPN cases that were surgically treated during the past 10 yr were retrospectively reviewed. Among these 18 patients, the offending arteries involved were the PICA in 12 (66.7%), AICA in 4 (22.2%), and both PICA and AICA in 2 (11.1%). The PICA were then classified into the following groups based on their anatomic features: type I: the PICA formed an upward loop at the level of the glossopharyngeal nerve and passed between the glossopharyngeal and vestibulocochlear nerves; type II: the PICA formed an upward loop at the level of the glossopharyngeal nerve and passed between the glossopharyngeal and vagus nerves or between the rootlets of the vagus nerve; and type III: the PICA passed between the glossopharyngeal and vestibulocochlear nerves without forming a loop. The AICA had only one running pattern. The offending arteries involved in GPN, mainly the PICA and/or AICA, were classified into 4 different types based on their anatomic features.

Glossopharyngeal neuralgia due to exposed glossopharyngeal nerve post tonsillectomy and transoral styloidectomy

&lt;p&gt;Glossopharyngeal neuralgia (GN) is a rare facial pain syndrome, characterized by paroxysm of excruciating radiating pain in the sensory distribution of the auricular and pharyngeal branches of glossopharyngeal and vagus nerves. In relation to the tonsil, the glossopharyngeal nerve passes deep to the styloid process and related muscles attaching to styloid process. The lingual branch of the glossopharyngeal nerve provides sensation to the posterior tongue and enters the tongue base by traveling through the constrictor muscles in the area of the lingulotonsillar sulcus. Post tonsillectomy fossa with exposed nerve causing intractable pain is a rare entity. We report a case of 64 year male patient, post tonsillectomy and transoral styloidectomy, with complaint of severe throat pain on left side for 2 years, radiating upwards to the ipsilateral ear, face and eye. Glossopharyngeal nerve and its branches were found exposed in the posterior and inferior aspect of tonsillar bed. Surgical resection of exposed glossopharyngeal nerve and its branches was carried out in view of failure to respond to oral carbamazepine. Patient was symptom free during 10 months of follow up visit. GN is a rare condition following tonsillectomy and styloidectomy. Radical dissection of tonsillar bed during tonsillectomy and not suturing tonsillar bed properly after styloidectomy can lead to exposure of glossopharyngeal nerve and its branches, resulting in intractable GN.&lt;/p&gt;

Olfactory, trigeminal, facial, glossopharyngeal and vagus nerves: links with sars-cov-2 and neurosemiological prospects

A brief review of olfactory, facial, glossopharyngeal and vagus nerves is presented, the first one functionally related to odoriferous chemosensory innervation in the nasal mucosa, the following four cranial nerves to endocranial headache and oropharyngeal mucosa for purposes of gustatory sensory transduction. These nerves are associated with symptoms in Covid-19 positive patients, which dysosmia, anosmia, dysgeusia, ageusia manifestation, among other neurosemiological characteristics. It is concluded that these semiological characteristics may be due to neurotropic and transynaptic mechanisms, therefore a more rigorous neurological examination should be performed on symptoms and signs of Covid-19 patients.

Transection of Gustatory Nerves Differentially Affects Dietary Fat Intake in Obesity-Prone and Obesity-Resistant Rats.

The current prevalence of obesity has been linked to the consumption of highly palatable foods and may be mediated by a dysregulated or hyposensitive orosensory perception of dietary fat, thereby contributing to the susceptibility to develop obesity. The goal of the current study was to investigate the role of lingual taste input in obesity-prone (OP, Osborne-Mendel) and obesity-resistant (OR, S5B/Pl) rats on the consumption of a high-fat diet (HFD). Density of fungiform papillae was assessed as a marker of general orosensory input. To determine if orosensory afferent input mediates dietary fat intake, surgical transection of the chorda tympani and glossopharyngeal nerves (GLX/CTX) was performed in OP and OR rats and HFD caloric intake and body weight were measured. Fungiform papillae density was lower in OP rats, compared with OR rats. GLX/CTX decreased orosensory input in both OP and OR rats, as measured by an increase in the intake of a bitter, quinine solution. Consumption of low-fat diet was not altered by GLX/CTX in OP and OR rats; however, GLX/CTX decreased HFD intake in OR, without altering HFD intake in OP rats. Overall, these data suggest that inhibition of orosensory input in OP rats do not decrease fat intake, thereby supporting that idea that hyposensitive and/or dysregulated orosensory perception of highly palatable foods contribute to the susceptibility to develop obesity.

Sodium-glucose cotransporter 1 as a sugar taste sensor in mouse tongue.

We investigated potential neuron types that code sugar information and how sodium-glucose cotransporters (SGLTs) and T1Rs are involved. Whole-nerve recordings in the chorda tympani (CT) and the glossopharyngeal (GL) nerves and single-fibre recordings in the CT were performed in T1R3-KO and wild-type (WT) mice. Behavioural response measurements were conducted in T1R3-KO mice using phlorizin (Phl), a competitive inhibitor of SGLTs. Results indicated that significant enhancement occurred in responses to sucrose and glucose (Glc) by adding 10mmol/L NaCl but not in responses to KCl, monopotassium glutamate, citric acid, quinine sulphate, SC45647(SC) or polycose in both CT and GL nerves. These enhancements were abolished by lingual application of Phl. In single-fibre recording, fibres showing maximal response to sucrose could be classified according to responses to SC and Glc with or without 10mmol/L NaCl in the CT of WT mice, namely, Phl-insensitive type, Phl-sensitive Glc-type and Mixed (Glc and SC responding)-type fibres. In T1R3-KO mice, Phl-insensitive-type fibres disappeared. Results from behavioural experiments showed that the number of licks and amount of intake for Glc with or without 10mmol/L NaCl were significantly suppressed by Phl. We found evidence for the contribution of SGLTs in sugar sensing in taste cells of mouse tongue. Moreover, we found T1R-dependent (Phl-insensitive) type, Glc-type and Mixed (SGLTs and T1Rs)-type fibres. SGLT1 may be involved in the latter two types and may play important roles in the glucose-specific cephalic phase of digestion and palatable food intake.