Anatomic features of the fetal round and oval windows, and their relations with the tympanic nerve.

OBJECTIVE: The study aimed to examine morphometric properties of the round window (RW) and oval window (OW) and to show their relation with the tympanic nerve (the Jacobson's nerve, JN) in human fetuses from the otologic surgeon's perspective. METHODS: Thirty temporal bones of 15 fetal cadavers (8 males, 7 females) aged with 24.40 ± 3.71 weeks were included in the study. The height, width and surface area of the RW and OW and also distance from the JN to the OW and RW were measured. RESULTS: The height, width and surface area of the RW in this work were measured as 1.48 ± 0.25 mm, 1.57 ± 0.37 mm, and 2.05 ± 0.69 mm2, respectively. The RW was detected as round-shaped (8 cases, 26.7%), oval-shaped (15 cases, 50%), and dome-shaped (7 cases, 23.3%). The height, width and surface area of the OW were measured as 1.42 ± 0.26 mm, 2.90 ± 0.44 mm, and 3.63 ± 0.74 mm2, respectively. The OW was observed as oval-shaped (15 cases, 50%), kidney-shaped (10 cases, 33.3%), D-shaped (4 cases, 13.3%), and trapezoid-shaped (1 case, 3.3%). The JN was found 1.21 ± 0.60 and 1.18 ± 0.54 mm away from the RW and OW, respectively. CONCLUSION: This study containing morphological data about the shapes, diameters and area of the RW and OW may be useful to predict surgical difficulty, and to select implants of suitable size preoperatively for the windows. Knowing the relationship between the JN and the windows can be helpful to avoid iatrogenic injuries of the nerve.

Post-tonsillectomy dysphagia secondary to glossopharyngeal nerve injury.

The glossopharyngeal nerve lies in close proximity to the tonsillar fossa making it susceptible to injury during tonsillectomy, though it is uncommonly injured in practice. We present a case of severe dysphagia due to glossopharyngeal nerve injury following tonsillectomy and demonstrate the efficacy of the McNeill Dysphagia Therapy Program (MDTP), a novel stepwise exercise-based rehabilitation program, in improving clinical outcomes. In patients with persistent, severe dysphagia following tonsillectomy, glossopharyngeal nerve injury should be on the differential diagnosis. The MDTP is one method by which clinicians may be able to treat this complex condition.

A New Neuropathologic Mechanism of Blood pH Irregularities After Neck Trauma: Importance of Carotid Body-Glossopharyngeal Nerve Network Degeneration.

OBJECTIVE: We created a neck trauma model by injecting blood into the sheath of rabbits' carotid bodies (CBs). Then we determined the relationship between neuronal degeneration of the CB due to hemorrhage of this organ and its clinical effects such as blood pH and heart rhythm. METHODS: The present study included 24 adult male New Zealand rabbits. The animals were divided into 3 groups: control (n = 5); sham (0.5 mL saline injected into CBs; n = 5); and study (CB trauma model; n = 14). pH values and heart rhythms were recorded before the experiment to determine the values under normal conditions, and measurements were repeated thrice in the days following the experiment. The number of normal and degenerated neuron density of CBs was counted. The relationship between the blood pH values, heart rhythms, and degenerated neuron densities was analyzed. RESULTS: Heart rhythms were 218 ± 20 in the control group, 197 ± 16 in the sham group (P = 0.09), and 167 ± 13 in the study group (P < 0.0005). pH values were 7.40 ± 0.041 in the control group, 7.321 ± 0.062 in the sham group (P = 0.203), and 7.23 ± 0.02 in study group (P < 0.0005). Degenerated neuron densities were 12 ± 4/mm3 in the control group, 430 ± 74/mm3 in the sham group (P < 0.005), and 7434 ± 810/mm3 in the study group (P < 0.0001). CONCLUSIONS: A high degenerate neuron density in the CB can decrease blood pH and hearth rhythm after neck trauma, and there might be a close relationship between the number of degenerated neurons and clinical findings (such as heart rhythm and blood pH). This relationship suggests that injury to the glossopharyngeal nerve-CB network can cause acidosis by disturbing the breathing-circulating reflex and results in respiratory acidosis.

Bilateral glossopharyngeal nerve palsy following tonsillectomy: a very rare and difficult complication of a common procedure.

OBJECTIVES: Tonsillectomy is one of the most commonly performed otolaryngological procedures. Bilateral palsy of the glossopharyngeal nerve is an exceedingly rare complication that can result in significant morbidity. This case report aimed to raise awareness of this complication and outline management strategies. CASE REPORT: A 31-year-old woman who underwent routine tonsillectomy presented with progressive numbness of the palate, dysgeusia, xerostomia, paraesthesia of the tongue and the feeling of something in her throat within 2 weeks of surgery. She reported the post-operative onset of snoring. Examination revealed a symmetrically low, 'dropped' soft palate. Over time, her symptoms have lessened, but dysgeusia and snoring remain. CONCLUSION: The position of the glossopharyngeal nerve in the tonsillar bed makes it prone to injury during tonsillectomy, especially if 'hot' methods are used. Bilateral injury can result in significant morbidity that can be difficult to treat. Patients should be warned about this risk and care should be taken to minimise it.

Vernet's syndrome after carotid endarterectomy.

Unilateral paresis of cranial nerves IX to XI is defined as Vernet's syndrome. We retrospectively assessed cranial nerve symptoms from the clinical records of 143 carotid endarterectomy patients. A flexible nasolaryngoscope was used to examine vocal fold movements in 73 patients. If vocal fold paresis (VFP) was confirmed, the patient also underwent magnifying laryngoscopy (for correct diagnosis of injury to the glossopharyngeal and vagus nerves). It was found from clinical records that 8 patients (6%) were confirmed to have cranial nerve symptoms corresponding to Vernet's syndrome; 7 patients (9 %) had VFP on nasolaryngoscopy. In 2 patients, magnifying laryngoscopy confirmed ipsilateral VFP, pharyngeal paresis, pharyngeal wall hypesthesia, and ipsilateral pharyngeal wall swelling. These 2 patients also had symptoms of injury to the accessory nerve. Damage to cranial nerves IX to XI probably occurred in the parapharyngeal space, based on the existence of posterior pharyngeal wall edema or swelling after carotid endarterectomy.