Kenzo Tsuzuki

Differential regulation of P2X3 mRNA expression by peripheral nerve injury in intact and injured neurons in the rat sensory ganglia

&NA; The P2X3 receptor is a ligand‐gated cation channel activated by the binding of extracellular adenosine 5′‐triphosphate (ATP), an agent that has been suggested to have a role in the nociceptive pathway after tissue and nerve injury. After peripheral nerve injury, both down regulation and up regulation of the P2X3 receptor in sensory ganglion neurons have been observed. The purpose of this study was to examine the precise regulation of P2X3 mRNA expression in primary sensory neurons after nerve injury. We used two nerve injury models in the rat, the transection of the tibial and common peroneal nerves and the transection of the infraorbital nerve, and observed dorsal root ganglion (DRG) and trigeminal ganglion neurons, respectively. P2X3 mRNA in both neuron populations was detected by in situ hybridization with an oligonucleotide probe that was confirmed by Northern blot analysis. To identify axotomized neurons, we examined the expression of activating transcription factor 3 (ATF3), which is regarded as a neuronal‐injury marker, using immunohistochemistry. In the DRG, the mean percentage of P2X3 mRNA‐labeled neurons relative to the total number of neurons increased from 32.7% in the naive rats to 42.7% at 3 days after injury. The mean percentage of P2X3 mRNA‐labeled neurons in ATF3 immunoreactive (ir) neurons was 29.5% at 3 postoperative days, which gradually decreased to 11.2% at 28 days after injury. In the trigeminal ganglion, the mean percentage of P2X3 mRNA‐labeled neurons was 36.9% at 3 days after injury, versus 26.0% in the naive rats. In the ATF3‐ir neurons, the mean percentage of P2X3 mRNA‐labeled neurons was 25.3% at 1 postoperative day and was reduced to 6.1% at 28 postoperative days. The finding that P2X3 mRNA in ATF3‐ir neurons decreased significantly after injury indicates that axotomized neurons decreased the expression of P2X3 mRNA, despite the increase in P2X3 mRNA relative to the total number of sensory ganglion neurons. These data strongly suggest that P2X3 mRNA expression increases in intact neurons and that P2X3 mRNA in intact neurons may play a role in the pathomechanism of post‐nerve injury in primary sensory neurons.

Difficulty of diagnosing Wegener's granulomatosis in the head and neck region

OBJECTIVE The objective of this study was to review the various clinical features associated with Wegeners granulomatosis (WG) in the head and neck region and to discuss the difficulty of diagnosing patients with early stage WG. METHODS Between January 1998 and August 2007, WG was diagnosed and treated in 16 patients at the Department of Otolaryngology, Hyogo College of Medicine. Clinical and operating records of these patients were analyzed retrospectively. Diagnosis was based on the Japanese criteria proposed by the Japanese Ministry of Health and Welfare in 1998. RESULTS Ten patients (62.5%) had a definite diagnosis of WG, and the other six patients (37.5%) had a probable diagnosis of WG. The period from the onset to diagnosis was between 1 month and 30 years. The generalized form of WG was observed in three patients (18.8%), and the limited form of WG was observed in the other 13 patients (81.2%). Nasal, aural, and ophthalmic symptoms were initially presented in 10, 3, and 3 patients, respectively. Cytoplasmic pattern antineutrophil cytoplasmic antibodies (cANCAs) and perinuclear pattern ANCA (pANCA) were positively detected in 68.8% (11/16) and 27.2% (3/11) of the patients, respectively. Five of 14 patients (35.7%) had pathologic features of WG in biopsy samples from the head and neck region. Three patients in whom a diagnosis of WG was difficult are presented, and immediate lessons of our experience were discussed. CONCLUSIONS This study emphasized the difficulty of diagnosing WG, particularly at an early stage and when limited to the head and neck region. The biggest challenge faced in diagnosing WG is that it requires a high index of suspicion. When WG was suspected, we should obtain an accurate medical history from patients and repeat serologic and histopathologic examinations.

Olfactory changes after endoscopic sinus surgery in patients with chronic rhinosinusitis

OBJECTIVE To address the controversy over whether olfactory function is improved or not after endoscopic sinus surgery (ESS) in patients with eosinophilic (ECRS) and non-eosinophilic chronic rhinosinusitis (non-ECRS). METHODS Between June 2006 and March 2012, 89 adult patients with CRS underwent ESS at Hyogo College of Medicine. There were 55 men and 34 women with a mean age of 53 years old, ranging from 23 to 79 years. The average follow-up period was 10.7 months (3-24) after ESS. Peripheral blood examination, sinonasal CT imaging, and four kinds of olfaction tests [self-administered olfaction test (SAOQ), visual analog scale (VAS), T&T recognition threshold tests (T&T) and intravenous olfaction test using prosultiamine] were performed. We diagnosed ECRS when (i) symptoms of nasal congestion and olfactory disorder, (ii) bilateral chronic rhinosinusitis with nasal polyps (CRSwNPs), (iii) peripheral blood eosinophilia (>7.0%), and (iv) ethmoid sinus dominant opacification in preoperative CT findings (i.e. ethmoid sinuses (E) were more bilaterally occupied than those of maxillary sinuses (M), E/M≥1), were completely fulfilled. We divided the patients into two groups of ECRS (group A) and non-ECRS (group B). Olfaction tests before operation, and at the 3rd, 6th, 12th, and 24th month postoperation were analyzed. The severity and therapeutic evaluation of olfaction were based on criteria of T&T recognition thresholds. RESULTS The mean SAOQ and VAS scores showed significant improvement within 6 months after ESS in both group A and group B. In total, the improvement rates were 52.0% (26/50) at 3 months, 58.5% (24/41) at 6 months, 40.5% (15/37) at 12 months, and 41.2% (7/17) at 24 months. The significant improvement of T&T recognition thresholds in group B was maintained for 24 months, whereas those in group A, showing transient improvement, deteriorated after 12 months or more. A significant difference in postoperative T&T recognition between groups A and B was found at the 12th postoperative month. In both A and B, 84% of patients had a response to prosultiamine (positive group) in the preoperative stage. T&T thresholds in the positive group were significantly better that those in the negative groups in the postoperative stage. CONCLUSION Olfactory disorders due to ECRS showed transient improvement that deteriorated as time passed after surgery. The olfaction in the non-ECRS patients recovered comparatively well. Postoperative olfactory results were unfavorable in patients without a preoperative reaction to prosultiamine.

Bilateral same day surgery for bilateral perforated chronic otitis media

OBJECTIVE Bilateral same day surgery has been performed rarely because of the risk of postoperative sensorineural hearing loss following conventional myringoplasty or tympanoplasty (CMT). Simple underlay myringoplasty (SUM) through the ear canal has been developed by Yuasa R, Saijo S, Tomioka Y, et al. Office closure of eardrum perforation with fibrin glue (in Japanese), Otolaryngol Head Neck Surg (Tokyo) 1989;61:1117-1122, which has little risk of sensorineural hearing loss. We tried bilateral same day surgery using this technique and evaluated its outcome. METHODS Of 86 cases with bilateral perforated chronic otitis media that we treated between 1995-1997, 25 cases underwent bilateral same day surgery. Bilateral SUMs was performed on seven patients, SUM and CMT on 16 patients, and bilateral CMTs on two patients. RESULTS Closure of perforation was successful in 18 patients (72%) on both sides and in seven patients (28%) on one side. Postoperative air-bone gap of less than 20 dB was achieved in 15 cases (60%) on both sides and in 23 cases (92%) on one side. CONCLUSION Bilateral same day surgery for bilateral perforated chronic otitis media is possible if the operative indications are considered.

Tympanosclerosis involving the ossicular chain: mobility of the stapes in association with hearing results

Conclusion. The preoperative bone conduction level provides not only prognostic information but also information on the mobility of the stapes in tympanosclerosis. The surgical results depend upon the stapes mobility. Objectives. We aimed to evaluate operative findings and hearing results of tympanosclerosis involving the ossicular chain, in order to understand the pathophysiology and to establish better surgical treatment of tympanosclerosis. Patients and methods. Between January 1998 and March 2004, 29 patients (29 ears) with tympanosclerosis involving the ossicular chain underwent tympanoplasty at our hospital. Patients with myringosclerosis only, or with an associated cholesteatoma, were excluded from this study. The clinical and operational records and pre- and postoperative pure tone audiograms were reviewed retrospectively. Results. Intact canal wall tympanoplasty was applied to all 29 patients. A non-staged operation was performed on 21 patients, and a staged operation was performed on the remaining 8 patients. In 25 patients (86.2%), the sclerotic lesion of the ossicles was located in the epitympanum. In the remaining four, the sclerotic lamella coated only the ossicular chain. On average, the preoperative air conduction hearing level of 57.9 dB was significantly improved to 46.3 dB after tympanoplasty. The success rate of middle ear surgery was 65.5% (19 of 29 patients), according to the criteria of the Otological Society of Japan. In 16 patients (55.2%), the mobility of the stapes was preserved (group A), while in the remaining 13 patients (44.8%), the stapes was fixed (group B). The mean preoperative bone conduction of 25.5 dB in group A was significantly better than that of 37.2 dB in group B. The hearing result significantly improved in group A but not in group B. The success rates were 75% (12 of 16 patients) in group A and 53.8% (7 of 13 patients) in group B.

Novel endoscopic scoring system after sinus surgery.

OBJECTIVE To propose a simple post-operative endoscopic scoring system for use after endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis (CRS), and to demonstrate the usefulness of this approach. METHODS Subjects comprised 116 patients (84 men, 32 women; mean age, 54 years) with CRS who were analyzed endoscopically and radiologically after ESS between 2006 and 2012. The study was designed as a case series with planned data collection in the setting of university medical centers. Patients were followed-up for ≥ 6 months after ESS (mean, 13.1 months). Both pre- and post-operative computed tomography (CT) findings of each sinus and olfactory cleft (OC) were scored according to the Lund-Mackay scoring system: 0, normal; 1, partially; or 2, completely occupied. CT score represents the total score expressed as a percentage of the maximum possible score (12 points per side). Post-operative endoscopic score (E score, %) was calculated as the maximum score according to physical findings on each operated sinus and OC: 0, normal; 1, partially diseased; or 2, completely closed. Post-operative course using E score was verified by comparison with the Lund-Kennedy (L-K) scoring system. RESULTS E score was easily and quickly determined. Interclass correlation coefficient among 10 otolaryngologists indicated high-level inter-rater reliability (0.922). E score correlated strongly with both CT score (n=116, p<0.0001, rs=0.755) and L-K score (n=79, p<0.0001, rs=0.723). CONCLUSION Endoscopic evaluation using E score for sinuses and OCs after ESS is a useful method, together with L-K score for the nasal cavity and radiological study.

Taste disturbance after stapes surgery--clinical and experimental study.

Conclusion: Most of the clinical cases experienced taste disturbance after stapes surgery, and in a few cases this disturbance persisted for a long time. The animal experiment suggested the role of geniculate ganglion (GG) cells in nerve generation. Objectives: To clinically examine taste disorder and its recovery after stapes surgery and experimentally demonstrate a role of GG. Patients and methods: Taste function after preservation of chorda tympani nerve (CTN) in stapes surgery was prospectively investigated with a questionnaire and electrogustometry (EGM). Further, expression of neurotrophic factors in GG after injury of CTN was examined by in situ hybridization histochemistry (ISSH) and RT-PCR. Results: Among the cases, 15/18 (83.3%) were associated with taste disturbance and 6/18 (33.3%) were associated with tongue numbness 2 weeks after surgery; however, the symptoms ceased in 14/18 cases (77.8%). Two weeks after surgery, the EGM threshold was found to be elevated in 15/18 cases (83.3%), while in 10/18 cases (55.6%), it did not decrease until 1 year after surgery. Expression of ISSH and amplified bands of BDNF and GFR increased at 7 and 14 days after nerve injury in ipsilateral GGs and also increased at 7 days on the contralateral side.

Therapeutic Evaluation of Outpatient Submucosal Inferior Turbinate Surgery for Patients with Severe Allergic Rhinitis

BACKGROUND Surgical treatment for inferior turbinate (IT) is selected to treat severe allergic rhinitis (AR) that is unresponsive to conservative treatment. This study aimed to determine the clinical effects of outpatient submucosal IT surgery (OSITS) on patients with severe AR. METHODS Between January 2008 and August 2012, 95 patients with severe AR who underwent OSITS at the Department of Otolaryngology, Hyogo College of Medicine, were retrospectively analyzed. There were 53 men and 42 women. Their mean age was 27 years (11-75 years). OSITS was bilaterally performed using a bipolar radiofrequency electrocautery under local anesthesia. Symptoms, QOL, and physical findings were evaluated using scores from both pre- and postoperative periods (average: 12.4 months), according to Practical Guideline for the Management of AR in Japan 2009. RESULTS In perennial AR, all mean scores of nasal symptoms, QOL, and physical findings significantly improved after OSITS (p < 0.05, n = 83). Nasal obstruction, sleep problems, and IT congestion were the most strongly affected. Eye symptoms were not influenced by OSITS. OSITS also showed significant effects on nasal obstruction and IT congestion in seasonal AR (p < 0.05, n = 12), but not sneezing, nasal discharge, and QOL. In terms of the efficacy, OSITS was beneficial in 90% of perennial AR cases and 75% of seasonal AR cases. Epistaxis (1%), vestibulitis (1%), and IT atrophy (4%) were observed after OSITS. CONCLUSIONS These data indicate that OSITS using radiofrequency electrocautery could be a beneficial therapeutic option in patients with severe AR.

Increase of preprotachykinin mRNA in the uninjured mandibular neurons after rat infraorbital nerve transection

An increasing number of studies are suggesting that the adjacent uninjured primary afferents contribute to the mechanisms of neuropathic pain following peripheral nerve injury. In this study, we report that transection of the infraorbital nerve, a major branch of the maxillary nerve, causes exaggerated face grooming to normally innocuous mechanical stimuli in the skin territory of the uninjured mandibular nerve, and increases the expression of preprotachykinin mRNA in the primary afferent neurons in the mandibular zone in the trigeminal ganglia. Considering the various functions of substance P in the sensory transmission process, the increase in preprotachykinin mRNA in the uninjured primary afferent neurons may be one of the mechanisms of pain-related behavior in this neuropathic pain model.

Expression of Activating Transcription Factor 3 and Growth-associated Protein 43 in the Rat Geniculate Ganglion Neurons after Chorda Tympani Injury

The purpose of this study was to evaluate the degree of damage in the geniculate ganglion and its target organ as a result of chorda tympani (CT) injury. We performed unilateral transection of the rat CT and examined expression of the activating transcription factor 3 (ATF3), a neuronal injury marker, and the growth-associated protein 43 (GAP-43), a regeneration-associated molecule. The mean proportion of ATF3-immunoreactive (ir) neurons in the geniculate ganglion was: 32% at 3 days after CT injury, but these neurons were never detected in the naive ganglion. Using in situ hybridization, the mean percentage of GAP-43 mRNA-labeled neurons (signal: noise ratio S 10) was observed to have increased significantly to 60% for 1-7 days after CT injury, while that in the naive ganglion was <15%. The results of morphological studies using scanning electron microscopy and immunohistochemistry indicated that atrophic change and reduction of protein gene-product 9.5-ir fibers in the denervated papillae, mainly in the intragemmal region, were observed after CT injury. Increase in GAP-43 mRNA, suggesting CT axonal regeneration, may have a role in recovery from taste disorders. However, this regenerative process may be involved in abnormal activity in the axotomized neurons or the adjacent intact neurons and so one must not disregard the existence of injured geniculate ganglions when considering the treatment of diseases that cause CT injury.