The pathogenesis of middle ear cholesteatoma is considered as the migrating process of keratinizing epithelia with hyperproliferative behavior to the middle ear cavity. In the present study, antibodies to the proliferating cell nuclear antigen (PCNA), which is a marker for proliferating cells in the S phase cell cycle, and specific cytokeratins (CKs) 5 and 19 were used in order to characterize cellular growth in middle ear cholesteatoma. Confocal laser scanning microscopy (CLSM) was employed to assess the density of antigen positive cells and to evaluate the fluorescence intensity quantitatively. PCNA positive cells were consistently identified in the basal and suprabasal matrix layers of cholesteatoma. Well-developed thick epithelia generally showed an intense PCNA staining compared to that of thin and flattened matrix tissues. The average cell densities positively stained for PCNA were 780.3cells/mm2 in 79 cholesteatoma specimens taken from 25 patients, and 257.8cells/mm2 in 8 control specimens of external meatal skin. The degree of cytokeratin expression as determined by fluorescent intensity of the labeled cells was correlated with the PCNA distribution in each sample. The presence of CK5 was broadly confirmed in cholesteatoma matrix. In contrast, a focal expression of CK19, which is known to reflect the presence of proliferating stem cells, was found in the basal layer of well-developed cholesteatoma matrix. A positive correlation was found between the degree of CK19 reactivity and the density of PCNA distribution (R=0.72, Pearson). Our results indicate that unusual growth patterns of cholesteatoma are mainly ascribable to the hyperproliferative activity of the basal and suprabasal layers, and their activities may vary considerably in each specimen.
The vestibular hair cell recovery after transtympanic administration of gentamicin (GM) in the gerbil was examined by use of immunocytochemical labeling for calmodulin, a hair cell marker. Nine animals were treated with transtympanic injection of GM for 5 days. Three animals were killed at 1 week, 2 weeks, and 4 weeks post-treatment (PT). Another two animals were untreated for a control. Twelve sections in the central region of the utricle of each animal were used for the calmodulin labeling. Hair cells stained with antibodies to calmodulin were 25.6/section at 1 week, 34.6 at 2 weeks, 38.4 at 4 weeks PT in number. The results indicated that hair cells showed recovery in number based on immunocytochemical labeling for calmodulin.
External Auditory canal cholesteatoma (EACC) is a rare lesion, with cholesteatoma more commonly occurring in the middle ear. We experienced three cases of EACC which required surgical removal. The sequestrated necrotic bone was also removed, and canaloplasty using free grafts of auricular conchal cartilage and temporal fascia was successively performed. The clinical findings of our EACC cases, and the pathology, etiology and treatment of EACC are discussed.
A retrospective analysis of 38 cholesteatomas operated by either type III (23 cases) or IV (15 cases) tympanoplasty is reported. The follow up periods were ranged from 7 months to 4.7 years and a mean period was 2.1 years. Canal wall down and complete mastoidectomy followed by meatal reconstruction and mastoid obliteration in one stage was performed if cholesteatoma expanded in and around the stapes. We evaluated postoperative hearing level according to the guideline of the Organizing Committee of Otology Japan (1987) in this study. Thirteen cases (72.2%) with primary operation with type III tympanoplasty improved in hearing level. From the technical point of view, a ossicular reconstruction with a cortical bone (60.6%) or residual ossicle (62.5%) was successful compared to a cartilage columella.(20.0%) Three patients were required surgical revision because of otorrhea or attic retraction, but residual cholesteatoma was observed in two cases. In conclusion, we propose that canal wall down technique and complete removal of cholesteatoma followed by meatal reconstruction using cortical bone and mastoid obliteration with bone chips are mandatory, if cholesteatoma is invaded in and around the stapes.
The MRI system used in this study was a new scanning sequence, 3D-CISS (Three dimensionalconstructive interference in steady state) with 1.5 Tesla. Ten normal ears and one ear with Mondini type anomaly were scanned and reconstructed. In Imagings of normal inner ears, the cochlea has three spiral layers; basal, middle and apical turns. Each turn was separated into three parts; the scala vestibuli, osseous spiral lamina and scala tympani. Three semicircular ducts, utricle and saccule were also reconstructed in one frame. In the inner ear of Mondini anomaly, 3D MRI showed cochlear aplasia, hypoplasia of semicircular ducts and widely dilated vestibule. The imaging was identical with findings of “common cavity”. The anomaly was easily recognized in 3D MRI more than in 2D imagings. The detailed and cubic imagings of the Mondini anomaly in 3D MRI could not be observed with conventional 2D MRI. 3D MRI is not invasive method and can scan a target very quickly.
Using an infrared CCD camera we observed spontaneous nystagmus (SPN) chronologically in 19 patients with sudden deafness and vertigo (V+group) and 25 patients with sudden deafness without vertigo (V-group) who were hospitalized within 10 days after the onset of hearing loss. As a control group, 20 healthy volunteers were examined. The results were as follws: 1) SPN were recognized in 100% of the V+group and in 96% of the V-group. No SPN was recognized in the control group. 2) The average period of persisting SPN was 33.4 days in the V+group and 29.7 days in the V-group. The average period of persisting vertigo in the V+group was 14.8 days. 3) The frequency of nystgmus was higher in the V+group than in the V- group. 4) Paralytic SPN was seen in 18 out of 19 cases in the V+group and in 23 out of 25 cases in the V-group. 5) Abnormal caloric responses were recognized in 6 cases (32%) in the V+group and in 2 cases (8%) in the V-group. 6) Average hearing level before and after the therapy were 95.3dB and 71.3dB, respectively, and hearing recovery more than 30dB was seen in 9 out of 19 cases (47%) in the V+group. On the other hand, in the V-group the average hearing level before and after the therapy were 77.2dB and 35.4 dB, respectively, and hearing recovery more than 30dB were seen in 18 out of 25 cases (72%). These results suggested that there were subclinical vestibular dysfunctions in most cases of the sudden deafness without vertigo, and these findings might reflect the extension and severity of the inner ear lesions.