Yasuo Mishiro

Tympanoplasty with and without mastoidectomy for non-cholesteatomatous chronic otitis media.

Objectives: Cases of non-cholesteatomatous chronic otits media (COM) were reviewed to determine whether mastoidectomy is helpful when combined with tympanoplasty for these conditions. Study design: A retrospective analysis of 251 ears with non-cholesteatomatous COM operated on by one surgeon (Y.M.) in an 11-year period was conducted. Methods: Patients in group A (n = 147) were treated by tympanoplasty with mastoidectomy. Patients in group B (n = 104) were operated on without mastoidectomy. Results: Graft success rates were 90.5% in group A and 93.3% in group B. There was no statistically significant difference. Graft success rates of discharging ears were 90.0% in group A and 85.7% in group B. Graft success rates of dry ears were 90.7% in group A and 94.4% in group B. There was no statistically significant difference between discharging ears and dry ears. The rates of the postoperative air–bone gap within 20dB were 81.6% in group A and 90.4% in group B, without a statistically significant difference. Conclusions: Mastoidectomy is not helpful in tympanoplasty for non-cholesteatomatous COM, even if the ear is discharging.

Rate of recovery of taste function after preservation of chorda tympani nerve in middle ear surgery with special reference to type of disease.

To study the recovery of function of the chorda tympani nerve, we examined by electrogustometry 79 patients (83 ears) with both preoperative normal function of the nerve and operative preservation of the nerve, every 2 days during hospitalization and at 6 months after surgery. For symptoms such as tongue numbness and taste disturbance, patients with noninflammmatory (NI) diseases (13/20 or 65.0%) showed a significantly higher rate of symptoms than did patients with chronic otitis media (COM; 13/35 or 37.1%) at 2 weeks after surgery (p = .032). The patients with NI diseases (5/20 or 25.0%) tended to show a higher rate of symptoms than did the COM patients (2/35 or 5.7%) or cholesteatoma patients (2/28 or 7.1%) at 6 months after surgery. The rate of recovery of the EGM threshold to normal at 2 weeks after surgery was significantly lower in NI disease patients (6/20 or 30.0%) than in COM patients (23/ 35 or 62.9%) or cholesteatoma patients (19/28 or 67.9%; p = .015 and .008, respectively). Thus, the patients with NI diseases had postoperative symptoms and elevation of EGM threshold more frequently than did the patients with inflammatory diseases.

Up-regulation of cochlear aquaporin-3 mRNA expression after intra-endolymphatic sac application of dexamethasone.

Abstract The final aim of the present study is to see if the endolymphatic sac is really available as a drug delivery system to have effect on the inner ear organs. In the present study, we examined effects of a single insertion of dexamethasone into the rat unilateral endolymphatic sac on mRNA expression of the inner ear aquaporin (AQP) family, transmembrane water transporters and putative endolymphatic fluid modulators, by means of real-time quantitative PCR. Only AQP-3 mRNA expression in the ipsilateral cochlea was significantly up-regulated in comparison with controls and the up-regulation was demonstrated both in dose-dependent and time-dependent manners. These findings suggest that the intra-endolymphatic sac steroids could make regulatory effects on the inner ear AQP-3 expression via vestibular aqueduct and modulate the homeostasis of endolymphatic fluids, encouraging the possibility that the endolymphatic sac could be a therapeutic window for the inner ear disease.

Effects of Exposing the Opened Endolymphatic Sac to Large Doses of Steroids to Treat Intractable Meniere's Disease

To enhance the effect of treatment for intractable Menieres disease, we exposed the opened endolymphatic sac to high concentrations of steroids. This technique — endolymphatic sac drainage and steroid instillation surgery — involves the application of a mass of prednisolone followed by absorbable gelatin sponges soaked in a high concentration of dexamethasone into a sac lumen opened and expanded with a bundle of absorbable gelatin film. These sponges are also placed around the sac and coated with biochemical adhesive so that the medicine is slowly delivered into the sac over a prolonged period of time by means of a natural sustained-release vehicle. The short-term results (6 to 14 months) in 12 patients with Menieres disease, including those in stage IV, treated by the above techniques showed that definitive spells were completely controlled in all cases. Hearing was improved, and annoyance due to tinnitus was decreased in all cases except one.

Eustachian tube function and habitual sniffing in middle ear cholesteatoma.

Objective: To investigate the incidence of habitual sniffing and the function of eustachian tube in middle ear cholesteatoma. Study Design: Prospective study. Setting: University hospital. Patients: One hundred thirteen consecutive cases of primary acquired cholesteatoma were operated on from July 2005 to December 2007, and they consisted of 78 pars flaccida type (69.9%), 25 pars tensa type (22.1%), and 10 unclassified large type (8.8%). As a comparison, 178 consecutive cases of chronic otitis media (COM) and 30 consecutive cases of otosclerosis were also examined. Methods: A questionnaire was administered regarding symptoms of patulous tube and habitual sniffing to alleviate ear symptoms. Eustachian tube function was examined by sonotubometry. Results: The eustachian tube function in cholesteatoma showed patulous type (25.7%), stenotic type (44.2%), and normal type (30.1%), whereas that in COM showed 11.2%, 25.3%, and 63.5%, respectively, and that in otosclerosis showed 6.7%, 16.6%, and 76.7%, respectively. The incidence of patulous type is significantly higher in cholesteatoma than in COM (p < 0.01) and in otosclerosis (p < 0.05). Habitual sniffing was found to be significantly higher in cholesteatoma (31/113, 27.4%) than in COM (9/178, 5.1%) (p < 0.001) and in otosclerosis (1/30, 3.3%) (p < 0.001). The existence of diseases on the contralateral side was significantly higher in cases with habitual sniffing (26/31, 83.9%) than in those without habitual sniffing (32/82, 39.0%) (p < 0.001). After the canal wall up method, postoperative retraction of the eardrum is significantly related to habitual sniffing continuing after the surgery. Conclusion: Patulous eustachian tube and habitual sniffing may play a role for pathogenesis of middle ear cholesteatoma.

The Investigation of the Recurrence Rate of Cholesteatoma Using Kaplan-meier Survival Analysis

Objectives: To investigate the recurrence rate of cholesteatoma using Kaplan-Meier survival analysis. Study Design: Retrospective study. Setting: Tertiary referral center. Patients: Three hundred forty-five patients with middle ear cholesteatoma operated on by the same surgeon between 1987 and 2002. Methods: The cumulative recurrence rate of cholesteatoma during a 5-year follow-up period was calculated using Kaplan-Meier survival analysis. Results: The overall 5-year recurrence rate was 11.8%. The recurrence rate increased with the follow-up time. The 5-year recurrence rate was 3.9% in patients treated with canal wall down tympanoplasty (CWDT) and 16.7% in patients treated with intact canal wall tympanoplasty (ICWT) or canal wall reconstruction (CWR) after CWDT with a significant difference (p < 0.01). The 5-year recurrence rate was 26.0% in patients operated on between 1987 and 1996 and 0.7% in patients operated on between 1997 and 2002, again with a significant difference (p < 0.001). Conclusion: Kaplan-Meier survival analysis should be used for calculating the recurrence rate of cholesteatoma. Although this analytic method further demonstrates that CWDT is a more reliable surgical method than ICWT/CWR in reducing cholesteatoma recurrence, clinical judgment should be exercised, and we continue to recommend that a flexible approach should be adopted in deciding whether to perform CWDT or ICWT/CWR for individual cases.

Long-term observation on hearing change in patients with chronic otitis media

OBJECTIVE Very few reports are available in the literature to clarify the natural long course of hearing change in an individual patient with chronic otitis media (COM). We reviewed hearing change in patients suffering from perforated COM without an operation. METHODS Eighty-seven ears of 70 patients had COM with tympanic perforation and were observed without an operation. The mean follow-up period was 10.7 years (5-22 years) and the mean age at the first examination was 51.3 years. To minimize the effect of aging, 23 patients with normal ear drums on the other side were further analyzed. RESULTS All 87 ears tended to show deterioration of hearing gradually under long observation. In 23 patients, hearing deterioration was 0.13 dB/year in the control side and 0.61 dB/year in the COM side (P < 0.02). Although elevation of bone conduction hearing level tended to be larger at high frequencies than at low and middle frequencies, there was no significant difference between COM and normal ears. CONCLUSIONS Air conduction hearing levels deteriorated with the passage of time and surgery is recommended at the early stage of COM to prevent progress of hearing loss.

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.

Taste function in elderly patients with unilateral middle ear disease.

Objective It is generally said that taste function deteriorates naturally with age. Taste function after middle ear surgery in elderly patients has not been clarified. Material and Methods The taste function of the chorda tympani nerve on the normal and diseased sides was examined before and after middle ear surgery using electrogustometry in 79 patients aged>60 years, and the findings were compared with those in 228 young and middle-aged patients. Results The threshold of electrogustometry on the normal side increased significantly with increasing age (p<0.0001). The rate of thresholds that were off the scale was highest in the>70 years age group. The preoperative threshold on the diseased side increased significantly with increasing age in patients with chronic otitis media (p=0.0029) and cholesteatoma (p<0.0001). In patients with chronic otitis media, the postoperative threshold of the>60 years age group tended to be higher than that of the<60 years age group. Conclusions These findings suggest that the taste function of the chorda tympani nerve deteriorated on the diseased side as much as on the normal side in elderly patients. Therefore, in most cases, we do not have to pay as much attention to the chorda tymapani nerve when performing surgery in elderly patients compared to young and middle-aged patients.

Horizontal canal type BPPV: bilaterally affected case treated with canal plugging and Lempert's maneuver.

A 54-year-old woman complained of positional vertigo. During 3 months’ observation, the patient showed mostly geotropic or apogeotropic nystagmus due to right canalolithiasis or cupulolithiasis, however, she sometimes showed nystagmus which suggested left horizontal canalolithiasis. We suspected that she suffered from bilateral horizontal canal type benign paroxysmal positional vertigo (BPPV) and performed Lempert’s maneuver for both directions, however, they were ineffective. She underwent canal plugging for right horizontal canal. After surgery she showed no positional nystagmus of right horizontal canal origin. However, apogeotropic nystagmus of the left horizontal canal origin was still observed. This nystagmus changed to geotropic nystagmus and finally disappeared following Lempert’s maneuver for the left side. Bilateral horizontal canal BPPV is difficult to be resolved, probably because physical treatment for one side would move debris to the cupula in the other canal. Canal plugging combined with Lempert’s maneuver to the other side is one treatment option for intractable bilateral horizontal canal BPPV.