The challenges still facing otologists intraoperatively are the inability to determine the patency of the Eustachian tube and the inability to inspect some hidden areas of the middle ear. The endoscope technology development may help to bridge this gap in our analysis of the middle ear cavities. Material, applications, advantages and disadvantages will be underlined for each otologic approaches: external ear canal, mastoid cavity and Eustachian tube. Endoscopy of the cerebellopontine angle (CPA) is a simple and helpful intraoperative refinement, which allows to reach the delicate and deep neurovascular components running through the CPA with minimal morbidity. Our standard practice combining surgical and endoscopic procedure was to use the retrosigmoid approach. Between 1993 to 2001, we applied such a procedure in various circumstances including tumor removal (395 cases) as well as neurovascular conflicts (421 cases).
In the recent study of cell death, dying cells judged by the TdT-mediated dUTP nick end-labeling (TUNEL) method have been classified as “apoptotic” and “non-apoptotic” cells. In this study, 12-day-old mouse embryos were used because of a high frequency of “natural cell death” due to variation in the inner ear morphology, and the percentages of “apoptotic” and “non-apoptotic” dying cells (ADC and NADC) among total dying cells in the inner ear were calculated. Observation of consecutive paraffin sections showed about 90% of the inner ear dying cells to be ADC and about 10% to be NADC. ADC and NADC TUNEL positive dying cells in resin sections observed by light microscopy were reexamined by transmission electron microscopy using a reembedding maneuver. ADC and NADC were then analyzed based on the classification of dying cells (types 1, 2, 3A, 3B) by Clarke. It was clear that ADC were the equivalent of typel (apoptotic) dying cells and NADC were the equivalent of type2 (autophagic) dying cells.
Immunohistochemical study of inner ear autoantibody in experimental autoimmune labyrinthitis is presented. Using a heterogonous bovine crude inner ear antigen (CIEAg) we were able to induce inner ear antibody in C57B/6 mice. In western blot assay, serum reacted several components of the bovine inner ear proteins which were mainly 55-65 kDa, 45-47 kDa and 200 kDa. IgG localization was consistently revealed around the vessels of the stria vascularis, the modiolus, and the bony labyrinth. IgG occasionally localized in the perilymphatic membranous surface, connective tissue in the spiral ligament, the ganglion cells, the cupula, the sensory epithel and the subepithelial layers of the vestibule. These results suggest that autoimmune vasculitis may play an important role in the pathogenesis of autoimmune labyrinthitis.
The chronic animal model of transient cochlear ischemia was successfully developed by bilateral vertebral artery occlusion for 15-min. in Mongolian gerbils. We investigated the effect of glutamate receptor antagonists on the degeneration of inner hair cell (IHC) following transient cochlear ischemia in this model. An alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)/kainate-type glutamate receptor antagonist was administered 10 min. before the ischemic insult. Hearing was assessed by recording compound action potentials (CAPs) before and after the ischemia. The degree of hair cell loss in the organ of Corti was evaluated in speciments stained with rhodamine-phalloidin and Hoechst 33342. On the seventh day after ischemia, the increases in the CAP threshold and the progressive IHC loss were significantly reduced in cochleae treated with DNQX (6-7-dinitroquinoxaline-2, 3-dione). These results suggest that the AMPA receptor plays a critical role in the development of the progressive IHC loss induced by ischemia/reperfusion injury in the cochlea.
Many classifications of ossicular chain reconstruction, which is a fundamental procedure in tympanoplasty, have been reported since Wullstein and Zoellner. In Japan, the Otomicrosurgery Research Team Surgical Terminology Committee proposed in 1972 a “classification and naming of surgical techniques for otitis media and its after effects (COMI)”. This view became the basic way of thinking concerning ossicular chain reconstruction for Wullstein types I, II, III (modified), and N (modified). In 2000 the Otological Society of Japan Terminology Committee proposed a new classification for classifying and naming sound conduction methods. Under this plan, the classifications III (modified) and N (modified) that had always been somewhat vague were clearly classified into “columella” and “interposition”, making it easier to evaluate improvement in hearing. Using the new proposal, we therefore classified in detail the surgical technique that had conventionally been regarded as type N (modified) and examined the results. Subjects were 48 patients who had undergone tympanoplasty N-c and N-i at our institution and whose hearing ability was followed for at least 6 months after the surgery. The results were applied to the guideline in reporting hearing results in middle ear and mastoid surgery (2000) proposed by the Otological Society of Japan Terminology Committee, and the hearing results examined. The difference in air conduction and bone conduction was no more than 15 dB in 4/32 cases of N-c (13%) and 6/16 cases of N-i (38%). However, hearing improvement was no more than 15 dB in 13/32 cases of N-c (41%) and 4/16 cases of N-i (25%). Furthermore, hearing level was no more than 30 dB in 6/32 cases of N-c and 2/16 cases of N-i (13%). Accordingly, there were 17/32 successful N-ccases (53%) and 10/16 successful N-i cases (63%). There have been a few reports such as this one that classify surgical technique in line with the new proposal and offer a detailed study.
Our purposes of surgical treatment for attic cholesteatoma are 1) complete removal or cnolesteatoma, 2) retainment of aerated tympanic and mastoid cavity, 3) hearing improvement by reconstruction of the tympanic membrane and ossicular chain, 4) preservation of function and morphology of the external and middle ear. Recently the number of cholesteatoma cases with otorrhea and granulation tissue is decreasing, and the number of cholesteatoma cases with well-aerated tympanic cavity and no granulation tissue in the mastoid cavity is increasing, by the development of antibiotics or the improvement of sanitary condition. Twenty-nine ears of 26 cases with attic cholesteatoma underwent canal wall up tympanoplasty with scutumplasty and onestage ossicular chain reconstruction during 1992-2001. We discussed the indication, complication, and hearing result of the cases operated by this method. The essential points of this operation are summarized as follows: 1) spread of the tympanic isthmus by anterior tympanotomy and posterior hypo tympanotomy, 2) attention to preserve the tympanic membrane and the tympanic annulus, 3) preservation of the manubrium of the malleus, 4) scutumplasty by using cartilage. Canal wall up tympanoplasty in this method consequently concludes in restricted defect of tympanic membrane, and so early epithelization is obtained after operation. We provide answer for the patient who requests hearing improvement by operation or shortening of duration of admission.
Tympanoplasty on only hearing ears of profound hearing loss more than 100 dB with persistent otitis media was performed on 5 patients in Numazu City Hospital during 1996-2001. Two of 5 ears were postoperative otitis media and 3 were adhesive otitis media. Preoperatively, even by fitting a hearing aid, practical hearing levels was not obtained. Our postoperative results of tympanoplasty in the patients were satisfactory. Compared with preoperative hearing level, postoperative hearing level showed improvement of 20 to 40 dB, and daily conversation was achieved at least by fitting a hearing aid in all the patients. Although no consensus exist regarding indication and management of tymoanoplasty for only hearing ears, careful operation minimizing the risk to labyrinthine function seemed most effective for making risky ear with only hearing ear and profound hearing loss into safe and stable ear.
Aeration of the middle ear cleft after tympanoplasty plays an important role in determining postoperative hearing and the recurrence of retraction cholesteatoma in patients with middle ear cholesteatoma. We investigated reaeration in each child with cholesteatoma after operation, and examined the relationship between the extent of reaeration and various clinical factors Forty children aged 10 years or under were included in this study. They underwent posterior canal wall reconstruction tympanoplasty for middle ear cholesteatoma during 1995-2001. We evaluated the extent of aeration of the middle ear about one year after the first operation based on temporal bone CT images. The extent of reaeration was classified into four categories;A) to the mastoid antrum, B) to the attic, C) to the mesotympanium, and D) no aeration. We also analyzed the aeration with respect to the various clinical factors in each child. As controls, the aeration of the middle ear of adult patients who underwent posterior canal wall reconstruction tympanoplasty for middle ear cholesteatoma was also investigated one year after the first operation. The middle ear of the children was significantly well-aerated compared with the adults after tympanoplasty. The children with otitis media with effusion exhibited a significantly poor aeration of the middle ear postoperativery. The children with cholesteatoma localized in the mesotympanum or localized lateral to the ossicles showed significantly better aeration than those with big cholesteatoma extending to the entire attic or the antrum. The present study clearly showed that reaeration of the middle ear is significantly better in children than in adults. This may be due to the fact that the middle ear is in the process of pneumatization in young children. The children with otitis media with effusion usually have eustachian tube dysfunction and are prone to respiratory infections which affect the reaeration of the middle ear. In children with cholesteatoma extending to the entire attic, to preserve the mucosa of the attic is usually difficult. Removal of the mucosa of the attic may delay the reaeration of the attic and the antrum.
Acute otitis media due to mucoid type Streptococcus pneumoniae (mucoid otitis media) in 9 adults was treated (10 ears) during the period from June 2000 to August 2002. They complained of severe otalgia, otorrhea, high fever and ear fullness. All the tympanic membrane showed hyperemia, bulging or blister with masked mastoiditis. Six cases showed bone conduction hearing loss. Recovery of the hearing loss delayed about 1.5 months. Tympanotomy was performed in all cases and a ventilation tube was inserted in 4 ears. All cases were treated by antibiotics. In 6 cases with bone conduction hearing loss, steroids and vitamins were administered. In all cases mucoid type Streptococcus pneumoniae was isolated. This pathogen was found to have pbp2x gene in this country, and to resist against cephem antibiotics. The antibiotics of the first choice against mucoid otitis media is penicillin.
We reviewed the postoperative complications of cochlear implantation for 44 patients, including 21 adults and 23 children. The major complications defined as what required surgical interventions were found in 4 patients (9%). These included wounds abscesses in 2 patients, electrode slippage in one, and device failure in one. The minor complications defined as self-limiting or settling with medical treatment and causing little distress to patients were found in 11 patients (25%); transient vertigo or dizziness in 5 patients, facial stimulations in 4 patients, and taste disturbances in 2 patients. The incidence of postoperative complications in the current study was similar to those reported in previous studies.
A 29-year-old woman underwent an operation for removal of infralabyrinthine petrous bone cholesteatoma. Her inner ear function was successfully preserved by introducing a rigid endoscope usually used for endonasal sinus surgery. The patient complained of dizziness and headache 9 years ago and CT examination revealed a tumor in her left petrous bone. She had been observed without any major symptoms for 8 years. However facial paralysis and hearing loss on the left side suddenly occurred last year, which recovered after one-week daily injections of steroid. The preoperative inner ear function was minimally impaired with 10dB hearing loss compared with the healthy side. Facial paralysis was not observed. The operation was conducted under the transmastoid approach using a rigid endoscope, which helped us to get a full operative view without destroying the bony labyrinth such as the semi-circular canals, cochlea and the facial canal. The cholesteatoma was successfully removed and the inner ear function was completely preserved. We concluded that the rigid endoscope was useful for the removal of petrous bone cholesteatoma of the infralabyrinthine type.
Adenoma that develops in the middle ear is still a rare disease in Japan, and only several cases of it have been reported so far. Adenoma of the middle ear is classified into two types. One is aggressive papillary type (APMET), and the other is mixed type (middle ear adenoma: MEA), which is clinically non-aggressive. A report was made of a 49-year-old patient with MEA. The only symptom was a feeling of ear fulness. A white mass was observed in front of the handle of the malleus on examination of the eardrum. The mass was removed under a diagnosis of congenital cholesteatoma. On pathologic examination, the mass was diagnosed as MEA. On immunohistochemical staining, tumor cells were positive for keratin, EMA, chromogranin A, synaptophysin, and CD56 suggesting neuroendocrine nature. The postoperative course of this patient has been satisfactory.
We encountered 2 patients with Turner syndrome showing auditory disorders. The first patient noticed progressive hearing loss around the age of 20 years, and visited out department due to acute sensorineural hearing loss. She showed improvement after treatments similar to that for sudden sensorineural hearing loss. The second patient was a 5-year-old female with recurrent otitis media since the age of 3 years. After insertion of a tympanostomy tube, she was followed up in outpatient department. Recurrent otitis media was suggested to be associated with brachycephaly due to cranial growth failure, high-arched palate, and impaired growth of the eustachian tube. Sensorineural hearing loss is considered to be due to damage in sensory hair cells and may develop at the lower age group, showing progression. Therefore, regular physical examinations, treatments, and hearing examinations are necessary in patients with Turner syndrome.