The pediatric larynx has the following definitive characteristics: the larynx in children is higher than in adults;the larynx is small and narrow as an airway; the epiglottis is soft and omega-shaped; and the aryepiglottic folds are shorter. Of the morphological features of the pediatric larynx, in this study we examined the morphology of the epiglottis and the length of the aryepiglottic folds retrospectively using flexible nasolaryngoscopic videos. The subjects were 282 patients generally treated as children and under 15 years of age during the 5-year period from May 2017 to April 2022, who visited our department of otorhinolaryngology. Of the 282 patients, 105 (37.2%) were found to have the omega-shaped epiglottis, and in neonates, infants, and pre-school children, it was found in one-third to one-half of the patients. A flat epiglottis similar to the epiglottis in adults was found not only in schoolchildren but also in neonates and infants. The morphology of the epiglottis was not significantly different between genders, but age and the presence of underlying disease resulted in significant differences. These findings suggested that the length of the aryepiglottic folds may serve as a subjective means of evaluation. The omega-shaped epiglottis was observed using an indirect laryngoscope. It is difficult to get a clear view and understand the laryngeal features using a flexible nasolaryngoscope. We believe it is easier to understand the epiglottis's omega shape if it is described together with the curled epiglottis.

Vagus nerve stimulation (VNS) therapy is a palliative surgical treatment for treatment-resistant epilepsy. Electrical stimulation is ascendingly transmitted to the cerebral cortex via an electrode placed on the left cervical vagus nerve, and it is thought that the frequency and degree of epileptic seizures are reduced by strengthening the inhibitory mechanism. However, there have been reports of side effects that are thought to occur from stimulation of other fibers of the vagus nerve, such as hoarseness, pharyngolaryngeal paresthesia, dyspnea, and dysphagia. We experienced a case in which VNS therapy could not be started due to severe dyspnea with wheeze and choking resulting from constriction of the glottis during VNS. Here we report the details of laryngeal findings and the course of this case, as well as a review of the literature.

Type 2 thyroplasty (TP2) using a titanium bridge (TB) is a standard surgery used to treat adductor spasmodic dysphonia (ADSD). We report 3 cases of broken TB after TP2. The patients complained of spasmodic or weak voice continuing after TP2, so a second TP2 was carried out. During the second TP2, in 2 cases the TB was seen to have previously been broken, and in 1 case the TB broke intraoperation. The broken TBs were checked by scanning electron microscope, and all sections showed characteristics typical of metal fatigue caused by repeated bending. If a TB is bent numerous times, it will break on the thyroid cartilage. However, so long as the central part of the TB remains unbroken, the voice does not become spasmodic. TBs should not be bent more than once, as repeated bending will cause the TB to break.

There are three causes of unilateral recurrent nerve palsy:postoperative, idiopathic, and tumor disease. When tumor invasion of the recurrent nerve is observed, nerve palsy is difficult to improve. In the present case, we experienced a case in which recurrent nerve palsy improved after chemotherapy for esophageal cancer. The patient was a 65-year-old man with advanced esophageal cancer (cT4bN2M1, cStage IVb) who was treated with CDDP+5-FU at the Department of Clinical Oncology of our hospital. He was referred to our department for close examination of his hoarseness, which had worsened since the start of treatment. Laryngoscopy revealed left vocal cord paralysis with arcuate changes, and CT scan revealed a primary tumor in the upper esophagus, multiple lymph node metastases, and lung metastases. The regimen was changed to nivolumab due to tumor progression. Laryngoscopy performed 205 days after the start of treatment showed improvement of left vocal cord paralysis. In general, nerve preservation is difficult in patients with malignant tumors due to direct nerve invasion or concurrent resection at surgery, and improvement of recurrent nerve palsy is not expected. Among peripheral neuropathies, however, in the case of neurapraxia, complete recovery of neuropathy is possible. In the present case, nerve compression by the cancer caused neurapraxia, and shrinkage of the cancer by chemotherapy was considered to have improved the recurrent nerve palsy.

Endoscopic cricopharyngeal myotomy (ECPM) is an alternative procedure with less invasiveness but equal effectiveness as traditional transcervical cricopharyngeal myotomy. Here, we report a 70-year-old man with insufficient oral intake after total laryngectomy. Computed tomography findings and videofluorography indicated a protruded lesion at the posterior wall of the pharynx, causing dysphasia. We performed ECPM, and postoperative videofluorography showed adequate entrance openings in the esophagus with no adverse effects. The patient became able to follow a normal diet again. Although ECPM is generally applied for patients with brainstem infarction, this surgical method is useful for postoperative stenosis of the pharynx attributable to the residual cricopharyngeal muscle.

Endoscopic laryngo-pharyngeal surgery (ELPS) was developed in Japan for superficial carcinoma of the pharynx or larynx. This method requires special instruments, such as malleable electrocauteries and curved forceps. We often use an electrocautery in hemostasis; however, an electrocautery alone may not be sufficient for thick blood vessels. Hemostasis by clipping is a helpful method in such cases, but many of the existing clip forceps are linear in shape, and there have been problems, such as inability to reach the surgical field exposed with a curved laryngoscope. Therefore, we developed a prototype of curved clip forceps for ELPS. The forceps are curved, and the distal end can be rotated. Using these forceps, it is now possible to reach almost all operative fields exposed with a curved laryngoscope. Using hemostatic curved clip forceps is expected to enable even safer trans-oral surgery.