Histamine is a major chemical mediator involved in the development of allergic rhinitis, inducing the symptoms of allergic rhinitis through binding to the histamine H₁ receptor (H1R). H1R is a rate-limiting molecule in histamine signaling, with the signaling increased with elevated receptor expression levels. We found that histamine-mediated stimulation of H1R induced upregulation of the H1R gene through protein kinase Cδ (PKCδ) activation, and that the elevated receptor expression levels in the nasal mucosa increased histamine signaling to further exacerbate the symptoms of allergic rhinitis. Antihistamines have three effects: they block histamine signaling mediated by H1R; they suppress histamine-induced upregulation of transcriptional activation of H1R; they suppress basal transcription of H1R even in the absence of histamine. The third effect may be a part of the inverse agonist action of antihistamines. Dexamethasone inhibits both basal transcription and transcriptional activation of H1R through suppression of extracellular signal-regulated kinase phosphorylation. We also found that pre-seasonal prophylactic treatment with antihistamines or intranasal corticosteroid sprays suppressed the gene expression of H1R in the nasal mucosa, resulting in the suppression of nasal symptoms in patients with cedar pollen pollinosis. Because H1R is an allergic rhinitis disease-sensitive gene, a new treatment strategy for allergic rhinitis targeting PKCδ has been suggested.

Histamine is a major chemical mediator that induces symptoms of allergic rhinitis through binding to the histamine H₁ receptor (H1R). The H1R gene is upregulated in the nasal mucosa of patients with pollinosis, and the expression level of H1R has been shown to be strongly correlated with the severity of the nasal symptoms in allergic rhinitis. However, suppression of H1R mRNA to the basal level by antihistamines alone failed to completely alleviate the nasal symptoms of allergic rhinitis, suggesting that some additional signaling may also be involved in the pathogenesis of allergic rhinitis. We showed that treatment with suplatast in combination with an antihistamine markedly alleviated the nasal symptoms in toluene-2,4-diisocyanate (TDI)-sensitized rats, an animal model of allergic rhinitis. Suplatast was shown to suppress both TDI-induced upregulation of the IL-9 gene in the nasal mucosa of TDI-sensitized rats and ionomycin-induced nuclear factor of activated T cells (NFAT) signaling-mediated IL-9 mRNA upregulation in RBL-2H3 cells. These data suggest that NFAT-mediated upregulation of IL-9 gene expression may also be involved, in addition to upregulation of H1R, in the pathogenesis of allergic rhinitis, and that suplatast suppresses NFAT-mediated signaling to alleviate the symptoms of allergic rhinitis. We then identified pyrogallol from the extract of Awa-tea, a local fermented tea, as an anti-allergic compound. Treatment with pyrogallol in combination with an antihistamine markedly alleviated the nasal symptoms in the TDI-sensitized rat model. Pyrogallol was shown to suppress both ionomycin-induced upregulation of IL-9 gene expression in RBL-2H3 cells and dephosphorylation/nuclear translocation of NFAT in BHK-21 cells. Furthermore, we isolated proanthocyanidin (LRPC) containing a gallocatechin tetramer from the extract of local Bittyu lotus root as an anti-allergic compound. Treatment with LRPC in combination with an antihistamine markedly alleviated the nasal symptoms in the TDI-sensitized rat model. LRPC was demonstrated to suppress both ionomycin-induced IL-9 mRNA upregulation in RBL-2H3 cells and TDI-induced IL-9 mRNA upregulation in the nasal mucosa of the TDI-sensitized rat model. These data suggest that both pyrogallol and LRPC suppress NFAT-mediated upregulation of IL-9 gene expression to alleviate the symptoms of allergic rhinitis. All these data further suggest that NFAT-mediated signaling could be a novel treatment target for allergic rhinitis.

Narrowband ultraviolet B (NB-UVB) phototherapy has been used clinically for the treatment of atopic dermatitis (AD). Therefore, NB-UVB phototherapy could also be effective for the treatment of allergic rhinitis (AR), because AR is also a Th2-dominant disease like AD. Recently, light-emitting diodes (LEDs) that emit selective UVB spectra at a wavelength of 310 nm (NB-UVB) have been developed, that are small enough for intranasal phototherapy. In order to develop NB-UVB phototherapy for AR, we first examined the effects of NB-UVB irradiation on the H1R gene expression in HeLa cells. We demonstrated that low-dose NB-UVB irradiation reversibly suppressed PMA-induced upregulation of H1R mRNA in a wavelength-specific and dose-dependent manner, without inducing apoptosis of the HeLa cells. We then conducted an in vivo study using toluene 2,4-diisocyanate (TDI)-sensitized rats, an animal model of AR. We demonstrated that intranasal NB-UVB pre-irradiation suppressed TDI-induced upregulation of H1R mRNA in the nasal mucosa in a dose-dependent manner, without induction of DNA damage, causing suppression of the TDI-induced nasal symptoms in this animal model of AR. These findings suggest that low-dose NB-UVB phototherapy could be effectively and safely applied for the treatment of AR. Finally, we have developed a prototype of an NB-UVB phototherapy device and demonstrated its safety in phase I and early phase II clinical trials.

Benign paroxysmal positional vertigo (BPPV) caused by a peripheral vestibular lesion is the most commonly encountered type of vertigo in clinical practice. BPPV has been classified according to the canal of origin, as posterior canal BPPV, anterior canal BPPV, and horizontal canal BPPV. In most cases of BPPV, the underlying pathophysiology is canalolithiasis, with a free-floating otolith in the semi-circular canal. Movement of the canalolithiasis with changes of the head position induces endolymphatic flow in the canal, resulting in the accompanying nystagmus. The rotation axis of the nystagmus is perpendicular to the affected canal. Torsional nystagmus can be induced by the Dix-Hallpike maneuver in patients with posterior BPPV. Direction-changing horizontal nystagmus can be induced by the supine roll maneuver in patients with horizontal BPPV. The direction-changing horizontal geotropic nystagmus is caused by canalolithiasis in the horizontal canal and the direction-changing horizontal ageotropic nystagmus is caused by cupulolithiasis. The canalith repositioning procedure is recommended for the treatment of BPPV. The purpose of this procedure is to relocate free-floating otolith from the posterior canal into the vestibule of the vestibular labyrinth. In this review, we provide the classification, pathophysiology, risk factors, natural course, and treatments of BPPV.

Unilateral vestibular dysfunction causes spontaneous nystagmus (SN) and deviations of posture and locomotion. However, the nystagmus and imbalance eventually recover gradually; this functional restoration based on the plasticity of the central vestibular system is called vestibular compensation (VC). VC is divided into static and dynamic VC. Static VC is further subdivided into initial and late processes. In the initial process, the neural activities of the contralateral medial vestibular nucleus (contra-MVe) are inhibited by the cerebello-vestibular inhibitory pathway, and in the late process, the neural activities of the ipsilateral medial vestibular nucleus (ipsi-MVe) are restored after unilateral labyrinthectomy (UL). The initial process of VC was evaluated by observing the decline of the frequency of SN after UL in rats. Diazepam, a GABA_A receptor agonist, facilitated the disappearance of SN after UL in rats, suggesting that the GABA_A agonist facilitated the initial process of VC. We then developed a new immunohistochemical method to evaluate the late process of VC in the rats after UL, and showed that the late process of VC can be demonstrated by the decline in the number of MK801 (an NMDA receptor antagonist)-induced Fos-positive neurons in the contra-MVe after UL. Thioperamide or betahistine, which are histamine H3 receptor antagonists, facilitated the disappearance of MK801-induced Fos-positive neurons in the contra-Mve after UL in the rats, suggesting that histamine H3 antagonists facilitate the late process of VC.

Vestibular rehabilitation is effective for providing relief from dizziness and improving imbalance in uncompensated patients with unilateral vestibulopathy. However, some patients are refractory to conventional vestibular rehabilitation. We developed a new vestibular rehabilitation method using virtual reality technology, to induce the sensory reweighting mechanism in the brain. In the preliminary study, vestibular rehabilitation using the virtual reality technology changed the balance control strategy in normal subjects. We then developed a new wearable device, Tilt Perception Adjustment Device (TPAD), that senses head-tilt vestibular information and transmits it to the mandible through vibration. Vestibular rehabilitation using TPAD improved dizziness and restored body sway and walking in patients with unilateral vestibulopathy who were refractory to conventional vestibular rehabilitation. We speculate that the vibratory somatosensory input of TPAD conveying head-tilt vestibular information serves as a substitute for the impaired processing of vestibular information by the brain, and a sensory reweighting mechanism changes the balance control strategy by reweighting sensorimotor dominance from vision to proprioception for posture and gait regulation in the brain in patients with unilateral vestibulopathy. Virtual reality and TPAD might be a promising tools to increase the efficacy of vestibular rehabilitation.

The neural mismatch hypothesis is widely accepted to explain the development of motion sickness. Essential to the neural mismatch hypothesis of motion sickness is the neural mismatch signal encoding spatial disorientation. We examined the neurochemical response to caloric stimulation with hot or cold water in the rat brain. Caloric stimulation with hot or cold water induced biphasic release of glutamate in the vestibular nucleus, indicating that the vestibular input is directly transmitted from the inner ear to the vestibular nucleus. However, hot or cold caloric stimulation induced monophasic release of histamine and acetylcholine in the hypothalamus and hippocampus respectively, suggesting that the neural mismatch signal, but not vestibular input itself, is transmitted to these regions. Our previous study showed that the hypothalamus plays an important role in the vestibule-autonomic reflex. Since the hippocampus has a spatial map, the possibility that the hippocampus generates the neural mismatch signal was examined. In our lesion study using a rat model, the hippocampal lesion aggravated motion sickness, suggesting that the hippocampus counteracts spatial disorientation. On the other hand, the cerebellar lesion had no effect on the development of motion sickness, suggesting that the cerebellum is not the origin of the neural mismatch signal.

Histamine H₁ receptors are involved in the development of the symptoms and signs of motion sickness and vertigo-induced vomiting. In the development of motion sickness and vertigo-induced vomiting, a neural mismatch signal encoding spatial disorientation activates the histaminergic neuron system in the hypothalamus, and the histaminergic descending impulse stimulates H₁ receptors in the emetic center of the brainstem. The histaminergic input to the emetic center through H₁ receptors is independent of the dopaminergic emetic inputs through dopamine D₂ receptors in the chemoreceptor trigger zone of the area postrema or the serotoninergic emetic inputs through serotonin 5HT₃ receptors in the visceral afferents. Antihistamines block the emetic H₁ receptors to prevent motion sickness and vertigo-induced vomiting. Central post-synaptic H₁, but not H₂ or peripheral H₁ receptors, play an important role in the development of motion sickness. Therefore, BBB-penetrating and sedating H₁ receptor blockers, but not non-BBB-penetrating and non-sedating H₁ receptor blockers or H₂ receptor blockers, prevent motion sickness and vertigo-induced emesis.

Once facial sequela has established in facial palsy patients with severe nerve impairment, the facial nerve functions can hardly be restored completely. The most unpleasant sequelae of facial palsy are facial synkinesis and facial contracture. First, we developed an objective method (% eye opening) to evaluate oral-ocular synkinesis, which refers to involuntary eye closure during mouth movements. We used % eye opening as an index of oral-ocular synkinesis, and showed that biofeedback rehabilitation using a mirror prevented the development of facial synkinesis in patients with facial palsy. We then developed a combined strategy of botulinum toxin injection and mirror biofeedback rehabilitation for the treatment of established facial synkinesis. A single injection of botulinum toxin provided transient relief from facial synkinesis, and the mirror biofeedback rehabilitation maintained this improved state for a long time in patients with facial palsy. Because facial synkinesis develops as a result of aberrant regeneration of an impaired peripheral facial nerve, we hypothesized that the mirror biofeedback rehabilitation induces cortical reorganization in the facial motor cortex. Furthermore, we developed an objective method for measuring the cheek asymmetry using a 3D scanner to evaluate another sequela of facial palsy, namely, facial contractures. We used the cheek asymmetry rate as an index and showed that a single injection of botulinum toxin provided transient relief also from facial contracture in patients with facial palsy.

The division of pediatric otology was established in the Department of Otolaryngology Head and Neck Surgery of Tokushima University Hospital in 2000, and continues to examine children with hearing loss living in Tokushima Prefecture. Pediatric otolaryngologists in the division of pediatric otology are engaged in the diagnosis and follow-up of hearing loss, hearing aid fitting, and performance of cochlear implant surgery in pediatric patients with hearing loss. In particular, they are also involved in performing genetic analyses and providing counseling, constituting multidisciplinary conferences for determining the indications for cochlear implantation, and cartilage-conduction hearing aid fitting.

Pediatric otolaryngologists in the division of pediatric otology have developed a medical and educational intervention program and follow-up system for children with hearing loss, in collaboration with speech language hearing therapists, teachers in the school for deaf children, and a school doctor. The medical and educational intervention program and follow-up system support children with hearing loss from the newborn period to their working years.

The pediatric otolaryngologists have persuaded the local governments to extend public financial support for the purchase of hearing aids for children with hearing loss. The public financial support service also covers purchase of hearing aids for children with mild to moderate hearing loss, purchase of cartilage-conduction hearing aids, and purchase of wireless communication systems for the classroom.

The speech recognition ability in children with unilateral hearing loss is similar to that in age-matched children with normal hearing in quiet and slightly noisy environments. However, in noisy environments, such as in working classrooms, children with unilateral hearing loss show reduced hearing ability as compared to children with normal hearing. An FM system, consisting of a microphone worn by the teacher and a receiver fitted in the normal ear of students with unilateral hearing impairment, is used in school classrooms. The FM receiver fitted into the normal hearing ear was shown to improve the speech recognition ability of children with unilateral hearing loss in noisy environments. Use of the FM system is recommended as an audiological management tool to overcome the listening difficulties of children with unilateral hearing loss in noisy school classrooms.

In the past, it was believed that unilateral hearing loss has a minimal impact on the speech and language development in children. However, several studies have suggested that some school-age children with unilateral hearing loss show language learning impairments. We found that the development of receptive vocabulary and verbal intelligence, but not that of performance intelligence, was delayed in more than a half of preschool-age children with unilateral hearing loss. However, children with unilateral hearing loss who showed delayed language development in preschool age often caught up with the children with normal hearing in terms of vocabulary and verbal intelligence after school admission. Future investigations are warranted to explore what kinds of auditory amplification or educational assistance may be effective to compensate for the delay in language development in children with unilateral hearing loss.

In Japan, infant health examinations and school medical checkups are well established and are useful for early identification of speech and language disorders in children. In Tokushima, we have well-developed advanced infant health examination and school medical checkup systems, where doctors in cooperation with speech-language-hearing therapists perform detailed screening of children for speech and language disorders. Our findings in regard to speech and language development in children through out the advanced infant health examination and school medical checkup systems suggest that the prevalence of delayed language development has recently increased in preschool-age and school-age children. We speculate that prolonged periods of time spent in watching TV, playing video games, using the internet, etc., may prevent children from experiencing normal social communication, leading to delays in language development.

In order to clarify human mucosal and systemic immunity against influenza viral infection, we measured the anti-influenza viral-specific secretory IgA (s-IgA) titers in the nasal secretions and IgG titers in the serum of adults. We used a safe and easy method for collecting nasal washings, the so-called nasal spray and aspiration (NSA) method, developed by us. The antiviral nasal s-IgA to total IgA ratio and serum IgG titers in 155 healthy adults and the changes in their levels at one month after subcutaneous vaccination were examined by an ELISA method in 2006. In addition, the induction and maintenance of antiviral nasal s-IgA and serum IgG responses throughout the first year after influenza infection were measured in 16 adults in 2007–2009. About 70% of the 155 healthy adults had nasal antiviral s-IgA against the A(H1N1) and A(H3N2) subtype and B type influenza viruses, and almost all had serum antiviral IgG prior to the vaccination. The mean serum antiviral IgG titers increased significantly after vaccination in the subjects with low pre-vaccination IgG titers, but not in those with high pre-vaccination IgG titers. On the other hand, no significant increase of the mean nasal antiviral IgA titer was found after the vaccination, irrespective of the pre-vaccine immune status. The antiviral s-IgA titers in the nasal washings in the patients with influenza virus infection were significantly lower at the onset of illness than that in healthy adults. While the serum antiviral IgG titers and HI titers varied widely, the HI titers were over 40 in 63% of patients at the onset of illness. Both the nasal s-IgA and serum IgG titers increased significantly at a later phase after the onset of illness, reaching their peak titers within day 21. The induced nasal s-IgA titers were maintained for 5 months, and returned toward the initial levels by 300 days after the onset of illness. Currently available subcutaneous influenza vaccines induce systemic immunity, with the appearance of antiviral IgG in the serum, in adults. However, subcutaneous vaccination did not elicit mucosal immunity (antiviral secretory IgA in the nasopharynx). Our findings also suggest that subjects with low levels of nasal antiviral secretory IgA are at an elevated risk for influenza infection.

The α-Fodrin N-terminal portion (AFN) autoantigen is involved in T cell-medicated autoimmune responses in patients with Sjögren’s syndrome. The infiltration of autoreactive T cells and the cleavage products of AFN were found in the salivary gland duct cells, and anti-AFN antibodies were detected in the serum of patients with Sjögren’s syndrome. The cleavage of α-Fodrin into the 120-kd fragment of AFN induced by Fas-mediated apoptosis and proliferative responses of T cells against AFN autoantigen were observed in the peripheral blood mononuclear cells of patients with Sjögren’s syndrome. AFN induced Th1-immune responses of T cells and accelerated downregulation of Fas-mediated T cell apoptosis in patients with Sjögren’s syndrome. These findings suggest that AFN autoantigen plays an important role in the development of Sjögren’s syndrome.

Dysphagia increases the risk of aspiration pneumonia. Cough reflex plays an important role in protecting the respiratory tract against inhalation of foreign particles. However, the sensitivity of the cough reflex is reduced in elderly subjects and patients with aspiration pneumonia. Capsaicin is the main component of red pepper, and stimulation of the pharyngolaryngeal mucosa with capsaicin induces the cough reflex by activating the sensory C-fibers. Stimulation of the auricular branch of the vagus nerve, the Arnold’s nerve, with 0.025% capsaicin ointment applied to the external auditory canal also improves glottal closure and the cough reflex via stimulating the Arnold-cough reflex in elderly patients with dysphagia. Repeated alternative application of 0.025% capsaicin ointment to each external auditory canal once a day for 2 weeks improved glottal closure and the cough reflex in a sustained manner in elderly patients with dysphagia, without the development of capsaicin defunctionalization. Moreover, a reduced incidence of pneumonia was observed in elderly dysphagic patients during the 6 months of daily alternative application of 0.025% capsaicin ointment to each external auditory canal, as compared with that recorded during the 6 months prior to the intervention. These findings suggest that daily auricular stimulation with capsaicin ointment is a potentially safe and promising intervention for prevention of aspiration pneumonia in elderly patients with dysphagia.

We developed a new method to evaluate dynamic narrowing of the pharynx induced by the Bernoulli effect producing maneuver (BEPM) of forced inspiration through the nose with the mouth closed in patients with obstructive sleep apnea syndrome (OSAS) using computer-assisted analysis of nasopharyngoscopic images. There was a significant correlation between the narrowing rate of the pharyngeal images obtained by nasopharyngoscopy during BEPM and the apnea index measured by single-night polysomnography. It is suggested that in addition to static pharyngeal narrowing, dynamic narrowing of the pharynx also contributes to the pathophysiology of OSAS. The pharyngeal narrowing rate during BEPM at a cut-off value of 50% combined with the body mass index (BMI) at a cut-off value of 25 kg/m² yielded a sensitivity of 93%, but a specificity of only 67% in differentiating simple snoring from OSAS. It is suggested that the pharyngeal narrowing rate during BEPM combined with the BMI is a promising index for predicting OSAS and that nasopharyngoscopy during BEPM could be a good OSAS screening method.

We developed the ratio of the apo/holo activities of angiotensin-converting enzyme (ACE ratio) in the serum as an index of the zinc nutrition status. The zinc nutrition status in patients with taste impairment was estimated based on the dietary zinc intake, serum zinc concentration and the ACE ratio in the serum. The results obtained in a series of our studies suggested that zinc deficiency is the predominant factor underlying taste impairment, even when the serum zinc concentrations were within the normal range, and that the ACE ratio is a more sensitive indicator of the zinc nutrition status than the serum zinc concentration. There were no differences in the dietary intake of zinc after adjustment for the energy intake or the serum zinc concentration between patients with taste impairment and age-matched healthy subjects. On the other hand, the ACE ratio in patients with taste impairment was significantly higher than that in age-matched healthy subjects. These findings suggest that zinc deficiency in patients with taste impairment is due to malabsorption of dietary zinc from the duodenum and jejunum, and not because of low dietary intake of zinc.

Patients with advanced head and neck cancer often experience dysgeusia as an adverse effect during chemoradiotherapy. Chemoradiotherapy-induced dysgeusia leads to malnutrition, which is a strong independent predictor of survival in patients with head and neck cancer. We found that chemotherapy specifically changed the gene expressions of T1R3 and T2R5 in the lingual mucosa, resulting in impairment of both umami and sweet tastes, and phantogeusia. The monosodium salt of L-glutamate (monosodium glutamate, MSG) is an umami compound that is used as a seasoning around the world. We examined the effects of dietary supplementation with MSG on chemotherapy-induced downregulation of T1R3 gene expression in the tongues of patients with head and neck cancer receiving chemoradiotherapy. MSG supplementation suppressed chemotherapy-induced dysgeusia by inhibiting chemotherapy-induced downregulation of T1R3 gene expression in the tongue, resulting in an increase of energy intake in the patients. Thus, dietary supplementation with MSG during CRT may be a promising nutritional intervention to improve the prognosis of patient with head and neck cancer.

Recent advances in head and neck surgery, such as transcanal endoscopic ear surgery, endoscopic laryngopharyngeal surgery, and transoral videolaryngoscopic surgery, have been introduced at Department of Otolaryngology Head and Neck Surgery of Tokushima University Hospital. A surgical navigation system and nerve-integrity monitoring system have also been introduced for computer-assisted head and neck surgery. Surgical training using human cadavers and virtual reality simulator are now well-recognized to be helpful for acquiring complex skills. Tokushima University Hospital developed the Clinical Anatomy Lab (CAL) for surgical training using fresh frozen cadavers, and our department started surgical training for acquiring skills in head and neck surgery in CAL. The virtual reality-simulated surgical training system is also adopted for surgical education of medical students and residents. Recently, our department launched the Tokushima ENT Skills Lab workshop for high-level training in surgical techniques.

In the present retrospective study, a total of 89 patients with laryngeal cancer who had received their primary treatment at the Department of Otolaryngology Head and Neck Surgery, Tokushima University Hospital, between January 2008 and December 2015 were enrolled. The patients consisted of 88 men and one woman, with a median age of 69 years (range 38–90 years). The cancer was located in the glottis in 68 patients and in the supraglottis in 21 patients. The distributions of the T and clinical stages of cancer in the patients with glottic cancer were as follows: T1s/T1a/T1b/T2/T3/T4: 4/26/6/18/10/4 patients; stage I/II/III/IV: 32/18/8/6 patients. The distribution of the T and clinical stages in the patients with supraglottic cancer were as follows: T1/T2/T3/T4: 3/9/7/2 patients; stage I/II/III/IV: 3/6/3/9 patients. Among the patients with glottic cancer, 33 patients underwent radiotherapy alone, 19 underwent chemoradiotherapy, 6 underwent transoral laser microsurgery, and 10 underwent total laryngectomy. Among the patients with supraglottic cancer, 3 patients underwent radiotherapy alone, 10 underwent chemoradiotherapy, 1 underwent vertical partial laryngectomy, and 7 underwent total laryngectomy. The disease-specific survival rate was 98.1% (stage I/II/III/IV: 100%/100%/100%/83.3%) in the patients with glottic cancer and 79.1% (stage I/II/III/IV: 100%/100%/100%/50%) in the patients with supraglottic cancer. The laryngeal preservation rates in the patients with glottic cancer according to the T stage were as follows: T1a, 84.6%; T1b, 66.7%; T2, 83.3%; T3, 30%; T4, 0%.

In the present retrospective study, a total of 42 patients with tongue cancer who had received their primary treatment at the Department of Otolaryngology Head and Neck Surgery, Tokushima University Hospital, between January 2010 and December 2015 were enrolled. The patients consisted of 24 men and 18 women, with a mean age of 63.7 years (range 30–93 years). The 5-year overall and disease-specific survival rates were 65.7% and 67.7%, respectively. The 5-year overall survival rates according to the disease stage were as follows: stage I, 85.7%; stage II, 85.7%; stage III, 66.6%; stage IVA, 36.1%. The 5-year overall survival rates according to the T stage were as follows: T1, 85.7%; T2, 63.1%; T3, 62.5%; T4, 50.0%. The 5-year overall survival rates according to the N stage were as follows: N0, 86.9%; N1, 50.0%; N2b, 34.0%; N2c, 0%.

Of the 22 (32%) tongue cancer patients with stage I or II disease, 7 developed occult nodal metastasis after the primary surgery. Out of the 9/15 patients with stage II disease who underwent elective neck dissection as part of the primary surgery, 2 developed occult nodal metastasis outside the dissection area; on the other hand, 4 of the 6 patients with stage II disease who did not undergo elective neck dissection developed occult nodal metastasis. These results suggest that elective neck dissection could improve the prognosis of patients with tongue cancer, however, the indications still remain controversial. We developed a new combined index of SUVmax of the lymph nodes in PET/CT by a weighting coefficient plus the minor axis diameter of the LN on CECT, and showed that this combined index might be a promising tool to improve the diagnostic performance of occult nodal metastasis and enable selection of clinical N0 patients with tongue SCC for elective neck dissection.

In the present retrospective study, a total of 44 patients with hypopharyngeal cancer who had received their primary treatment at the Department of Otolaryngology Head and Neck Surgery, Tokushima University Hospital, between July 2010 and June 2015 were enrolled. The five-year overall survival and disease-specific survival (DSS) rates were 53% and 65%, respectively. In the 41 patients who underwent radical treatment (median follow-up period: 64 months), the T status was identified as an independent predictor of the DSS and distant metastasis-free survival (DMFS) rates, and the N status was found to be an independent predictor of the DSS, regional control, and DMFS rates. The five-year DMFS rate in the patients with T3 or T4 disease who had undergone total pharyngolaryngectomy (TPL) after induction chemotherapy (ICT) was significantly higher (67%) than that in the patients who had undergone TPL alone (33%). This finding suggests that ICT may suppress distant metastasis in patients with advanced, but resectable, hypopharyngeal cancer.

In the present retrospective study, 55 patients with cholesteatoma who received tympanoplasty at Department of Otolaryngology Head and Neck Surgery, Tokushima University Hospital, between April 2010 and March 2014 were enrolled. The success rate of hearing improvement after tympanoplasty was 69.1% in all patients with cholesteatoma except congenital cholesteatoma, 73.7% in patients with pars flaccida cholesteatoma, and 64.3% in patients with pars tensa cholesteatoma. Canal wall-down mastoidectomy+canal wall reconstruction with soft materials+meatoplasty was performed in 53 out of the 55 patients; in the remaining 2 patients, transcanal atticotomy with scutumplasty was performed. Type III or IV tympanoplasty with columella was performed in most patients. A cartilage autograft was used for ossiculoplasty. No recurrence of cholesteatoma was reformed until 80.7 months after surgery. Staged tympanoplasty was performed in 20 patients and residual cholesteatoma was found in 6 patients at the revision tympanoplasty. In other 49 patients, however, no residual cholesteatoma was identified after the surgery.

Japanese cedar (JC) pollinosis is the most common form of allergic rhinitis (AR) in Japan, and its prevalence is only increasing. Now, more than one-third of Japanese people are estimated to suffer from JC pollinosis. Recently, sublingual immunotherapy (SLIT) with a standardized JC pollen and house dust mite (HDM) extract has been adopted in Japan for treatment of the respective forms of AR. At our department, SLIT with JC pollen and HDM significantly improved the nasal symptoms in patients with JC pollinosis and HDM-induced AR, respectively. The improvement became manifest from the first year of SLIT and remained sustained thereafter. SLIT with JC pollen decreased the Athens Insomnia Scale scores during the pollen season in patients with JC pollinosis. These findings suggest that SLIT with JC pollen suppresses nasal symptoms, leading also to improvement in AR-related sleep disturbance. Posterior nasal neurectomy (PNN) is effective for suppressing nasal discharge and sneezing in patients with refractory AR. Our questionnaire survey showed that improvement of the nasal symptoms, remained sustained for at least 5 years in patients with refractory AR who underwent PNN at our department. Our findings suggest that the long-term prognosis after PNN is satisfactory in patients with refractory AR.

In the present study, we enrolled a total of 506 patients who visited the Department of Otolaryngology Head Neck Surgery, Tokushima University Hospital, complaining of vertigo or dizziness between January 2017 and December 2020. Patients were diagnosed based on the diagnostic criteria prescribed by the Japan Society for Equilibrium Research. The age distribution of the patients showed a peak in the seventh to eighth decade. The most common peripheral vestibular disorder was benign paroxysmal positional vertigo (36%), followed by Meniere’s disease (11%). Central vestibular disorder was diagnosed in 11% of patients. The percentage of patients in whom the diagnosis remained unknown was 7%, which was lower than the percentage of 21% determined in our previous survey conducted in 2005. The new diagnostic criteria for vestibular migraine, persistent postural-perceptual dizziness, and vestibular paroxysmia, and the new equilibrium function tests, including vestibular evoked myogenic potential and video head impulse test were useful for differential diagnosis.