Yoshihisa Ueda

Conditioning the Cochlea to Facilitate Survival and Integration of Exogenous Cells into the Auditory Epithelium

The mammalian auditory epithelium (AE) cannot replace supporting cells and hair cells once they are lost. Therefore, sensorineural hearing loss associated with missing cells is permanent. This inability to regenerate critical cell types makes the AE a potential target for cell replacement therapies such as stem cell transplantation. Inserting stem cells into the AE of deaf ears is a complicated task due to the hostile, high potassium environment of the scala media in the cochlea, and the robust junctional complexes between cells in the AE that resist stem cell integration. Here, we evaluate whether temporarily reducing potassium levels in the scala media and disrupting the junctions in the AE make the cochlear environment more receptive and facilitate survival and integration of transplanted cells. We used sodium caprate to transiently disrupt the AE junctions, replaced endolymph with perilymph, and blocked stria vascularis pumps with furosemide. We determined that these three steps facilitated survival of HeLa cells in the scala media for at least 7 days and that some of the implanted cells formed a junctional contact with native AE cells. The data suggest that manipulation of the cochlear environment facilitates survival and integration of exogenously transplanted HeLa cells in the scala media.

Long-Term Postoperative Vocal Function after Thyroplasty Type I and Fat Injection Laryngoplasty

Objectives: We evaluated the differences in the long-term functional results of medialization thyroplasty type I (MT) and autologous fat injection laryngoplasty (FIL) in patients with unilateral vocal fold paralysis. Methods: Forty-one patients underwent MT, and 73 patients underwent FIL. The voice functions before and after both surgeries were examined by aerodynamic, pitch and intensity, and acoustic analyses. The postoperative voice examinations were performed 12 months (median) after the MT, and 4 years (median) after the FIL. The differences between the preoperative and postoperative parameters were examined with a paired t-test for each group separately. For each variable, a comparison of the effects of surgery was conducted with an analysis of covariance model, with the change between the preoperative and postoperative values as the dependent variable and the preoperative value as the covariate. Results: In both groups, all parameters significantly improved after surgery. In particular, there was a significant difference for the postoperative acoustic analyses. However, the aerodynamic analysis after FIL improved more significantly in comparison to that after MT because of the respiratory handicap. Conclusions: We found that MT and FIL provided almost the same effectiveness, and that both surgeries were reliable in improving the vocal function in patients with vocal fold paralysis.

Surgical treatment of labyrinthine fistula in patients with cholesteatoma

Labyrinthine fistula is one of the most common complications of chronic otitis media associated with cholesteatoma. The optimal management of labyrinthine fistula, however, remains controversial. Between 1995 and 2005, labyrinthine fistulae were detected in 31 (6 per cent) patients in our institution. The canal wall down technique was used in 27 (87 per cent) patients. The cholesteatoma matrix was completely removed in the first stage in all patients. Bone dust and/or temporalis fascia was inserted to seal the fistula in 29 (94 per cent) patients. A post-operative hearing test was undertaken in 27 patients; seven (26 per cent) patients showed improved hearing, 17 (63 per cent) showed no change and three (11 per cent) showed a deterioration. The study findings indicate that there are various treatment strategies available for cholesteatoma, and that the treatment choice should be based on such criteria as auditory and vestibular function, the surgeons ability and experience, and the location and size of the fistula.

Effect of tympanic membrane perforation on middle-ear sound transmission.

Tympanic membrane perforation causes a sound conduction disturbance, and the size of this conduction disturbance is proportional to the perforation area. However, precise evaluation of perforation size is difficult, and there are few detailed reports addressing this issue. Furthermore, such evaluation becomes more difficult for irregularly shaped perforations. This study conducted a quantitative evaluation of tympanic membrane perforations, using image analysis equipment.A significant correlation was found between the degree of sound conduction disturbance and the perforation area; this correlation was greater at low frequencies following a traumatic perforation. The conductive disturbance associated with chronic otitis media was significantly greater at low frequencies. Circular perforations caused only minor conduction disturbance. Perforations in the anteroinferior quadrant were associated with greater conduction disturbance. Traumatic spindle-shaped perforations and malleolar perforations were associated with greater conduction disturbance.

New silicone tube placement therapy for patients with an anterior glottic web.

An anterior glottic web in adults comprises a bridge of scar tissue commonly formed as a result of iatrogenic laryngeal injury. Traditionally, procedures such as transcervical midline thyrotomy and keel placement have been used to repair this condition. However, we recently repaired an anterior glottic web using a new surgical procedure involving a silicone tube instead of a keel. We herein report this case, in which we placed a silicone tube at the anterior commissure after resection of an anterior glottic web, under endolaryngeal microsurgery, without performing a tracheostomy.

Epithelioid sarcoma of the neck: case report

Epithelioid sarcoma is an aggressive, malignant tumour of the soft tissue which tends to arise in proximity to large tendons and aponeuroses. We report the case of a patient presenting with an epithelioid sarcoma arising in the neck. A 56-year-old man was referred with a three-year history of a sensory disorder as well as a slowly growing mass in his right neck. The patient underwent resection of the tumour by means of a conservative neck dissection. The final diagnosis, based on the histological and immunohistochemical findings, was epithelioid sarcoma. Radiotherapy was performed after the operation. The post-operative course was uneventful, and there was no local recurrence or distant metastasis.

Analysis of the Surgical Treatment for Middle Ear Cholesterol Granuloma

Middle ear cholesterol granuloma is still an intractable ear disease, and its pathogenesis has not been clearly demonstrated. In this study, we evaluated treatment of middle ear cholesterol granuloma.We reviewed middle ear cholesterol granuloma in 16 ears that underwent surgical treatment at Kurume University Hospital between 1990 and 2006.Cases that were healed by ventilation tube insertion only and those combined with other middle ear disease such as cholesteatoma were excluded from this study. We analyzed the relation between preoperative findings of the tympanic membrane and postoperative course. Preoperative findings of the tympanic membrane were grouped into the swollen type or retracted type. The cases that underwent myringotomy more than twice, showed persistent otorrhea from the tympanic ventilation tube, or the ventilation tube was missed were classified as showing a poor postoperative course. Cases without the above symptoms were classified as showing a good postoperative course. The hearing results were analyzed using the Guidelines for Evaluating Hearing Results after Middle Ear and Mastoid Surgery published by the Otological Society of Japan (2000).The postoperative courses of patients with a swollen tympanic membrane were significantly poorer. The postoperative courses of those with a retracted tympanic membrane and those undergergoing ossicular chain reconstruction showed significantly better results. However, 3 of 4 cases showing swollen tympanic membrane achieved a good passage. Such cases underwent posterior tympanotomy with ossicular chain reconstruction.Success rate for hearing improvement at about 14 post operative days was 75%. Yet, beyond 6 months postoperatively, the success rate deteriorated to 62.5%. Cases showing a poor hearing result at 14 postoperative days never showed a permanently improved hearing result.To acquire better postoperative results in patients with swollen tympanic membrane, posterior tympanotomy with ossicular chain reconstruction is highly recommended.

Two Cases of Soft Tissue Tumor Arising in the Deep Neck

We encountered two rare cases of soft tissue tumor arising in the deep neck. The first case was a 29-year-old woman diagnosed as having pseudomalignant osseous tumor. At surgery, a circumscribed, hard mass was found in the deep portion and adhered to the cervical vertebra. The mass was extirpated together with a layer of the surrounding macroscopically intact tissue. The post-operative course was uneventful. The second case was a 59-year-old man diagnosed as having epithelioid sarcoma. At surgery, a circumscribed, invasive mass was found in the deep portion and adhered to the cervical vertebra. The mass was excised together with adjacent muscle tissue and fat tissue. The post-operative course was uneventful. Immunohistochemical evidence in these cases are also presented.

P101: Intra-Arterial Infusion Chemotherapy for External Ear Cancer

OBJECTIVES: In the treatment of carcinoma of the external auditory canal (EAC), surgical resection has mainly been applied for patients with external ear carcinoma. However, surgical resection severely compromises the quality of life due to sacrificing of organ function. For organ preservation, superselective intra-arterial (IA) rapid infusion chemotherapy was combined with radiotherapy against carcinomas of the EAC. METHODS: Stages, feeding arteries, and outcomes were reviewed. Tumors were staged according to the Pittsburgh staging system. Chemotherapy was administered intra-arterially in the angiography suite via transfemoral catheterization of the feeding arteries. The patients received up to four weekly infusions of cisplatin (100 mg/body). The patients received external beam radiation simultaneously with IA cisplatin infusion chemotherapy at a dose of 2.0 Gy per fraction once daily five days a week with photon beam energy of 6MV (total dose of 60Gy). RESULTS: Four patients underwent superselective IA infusion chemo-radiotherapy. The median follow-up period was 23 months ranging from 12 to 42 months. Two patients were staged as T2 and other patients were staged T3 and T4. All patients were free from neck metastases. Cisplatin was delivered through the posterior auricular artery in three patients and the superficial temporal artery in one patient. Complete response (CR) was obtained in all four patients. Overall toxic side effects were modest. CONCLUSIONS: Surgical treatment of carcinoma of the EAC has always caused functional disturbances such as hearing loss even at its early stages. Superselective intra-arterial infusion chemotherapy can be an effective organ preservation treatment with high cure rates.