[Histological and ultrastructural aspects of oto-mastoid cholesteatoma in children]

Cholesteatomas were intraoperatively removed from subjects under 14 years of age presenting widespread cholesteatoma with bone erosion. The samples were studied under light and transmission electron microscopy in order to consider the features of inflammation and bone erosion. The results showed that the perimatrix of cholesteatoma in children is rich in mononuclear inflammatory elements and generally presents the features of chronic, as well as acute, inflammation. The perimatrix infiltrates and erodes the surrounding bone. Next to the resorption areas many areas were observed having new bone the surface of which is lined with osteoblasts. The new bone formation activity is marked in these cases of childhood cholesteatoma and appears to be an attempt at spontaneous repair which is thwarted by the persistence of inflammation.

Patterns of epithelial migration in the unaffected ear in patients with a history of unilateral cholesteatoma

Epithelial migration in a centrifugal manner is an established phenomenon in the normal human tympanic membrane. This pattern of migration is symmetrical in both ears of any one individual. We present a prospective study on the pattern of tympanic ink dot migration on the normal drum, in patients with a history of cholesteatoma in one ear. It was demonstrated that patients who develop cholesteatoma have a normal migratory pattern and rate in the unaffected ear. The conclusion from this study is that defective migration is not the initiating factor in the development of acquired cholesteatoma.

Middle ear cholesteatoma extending into the petrous apex: evaluation by CT and MR imaging

CT and MR imaging findings were reviewed in four cases of acquired cholesteatoma of the middle ear that extended medially into the petrous apex and middle cranial fossa. In one case the lesion further extended anteromedially into the sphenoid sinus. CT demonstrated the lesions as nonenhancing hypodense masses with bone destruction, extending medially from the middle ear cavity to the petrous apex region. On MR imaging, the lesion was slightly hypointense relative to brain on T1-weighted images and hyperintense on T2-weighted images. MR imaging clearly delineated the extraaxial location of the lesion and associated brain displacement. The medial extension of the cholesteatomas seems to have proceeded via a detour around the bony labyrinth into the petrous apex region by following normal pathways of temporal bone pneumatization.

Tympanic membrane microstructure in experimental cholesteatoma

This study assessed changes in tympanic membrane microstructure associated with cholesteatoma development following middle ear application of 50% propylene glycol in chinchillas. Although the epidermal layer of the tympanic membrane (TM) was destroyed immediately after propylene glycol application, the epidermal basal lamina remained intact and appeared to serve as a substrate for regrowth of epidermis over the TM. During the initial phase of epidermal repair (4 to 7 days after propylene glycol administration), pseudopodial processes from the epidermal cells occasionally penetrated the basal lamina; however, no migration of epidermis into the lamina propria occurred at that time. The basal lamina remained largely intact until about 2 weeks, when it became fragmented in some areas, so that sizable gaps appeared. Hyperplastic epidermal cells then migrated through the gaps into the rapidly proliferating connective tissue of the lamina propria. At 2 to 4 weeks, degenerative changes were observed in portions of the fibrous layer, which underwent phagocytosis by foreign body giant cells. This process created defects in the fibrous layer which permitted invasion of epidermis to the medial portion of the lamina propria. The epidermis subsequently reached the medial side of the TM in areas where there was incomplete repair of the mucosal layer.

Allograft tympanoplasty: predictive value of preoperative status

The functional and anatomical results of a series of 181 consecutive allograft tympanoplasties for ears with drum perforation and an intact ossicular chain were retrospectively reviewed and related to preoperative factors. Drum closure was realized in 92% (166 of 181 cases evaluated 1 year after surgery), and 96.6% of the reconstructed drums were still intact 3 years after surgery (118 cases evaluated). An air-bone gap of less than 21 dB was reached in 79.6% (of a total of 162 cases) 1 year after surgery, and in 78% (of a total of 118 cases) 3 years after surgery. Age, contralateral pathology, the wet or dry status of the ear preoperatively, and the preoperative air-bone gap had no influence on anatomical results. The preoperative air-bone gap did not predict the postoperative air-bone gap. The influence of age and existence of contralateral pathology on hearing gain was only visible in some of the strictly defined patient groups. The wet preoperative status of the ear generally predicted lower functional gain.

The inferiorly based superior tympanomeatal flap for removal of congenital cholesteatoma

We believe that the IB-STMF is preferable to the P-TMF for removal of a congenital cholesteatoma from the anterior superior portion of the mesotympanum. Though developing an IB-STMF may require extra time and special care to avoid tearing the flap, the exposure that is achieved affords the best chance for complete removal of the mass, thus decreasing the chance for persistence or recurrence of the lesion.

Ear involvement in the yellow nail syndrome

Recognized features of the yellow nail syndrome include yellow nails, lymphedema, and pleural effusions. We report a patient with the additional feature of keratosis obturans, which may be a manifestation of this syndrome in the external ear.

Inner ear cholesteatoma and the preservation of cochlear function

Labyrinthine destruction by direct cholesteatoma invasion has always been considered a serious threat to the inner ear function. A number of reports in the literature have cited both patients who had preservation of hearing despite widespread erosion of the labyrinth by cholesteatoma and patients who had retained auditory function despite surgical removal of the matrix from the labyrinth. In most cases the vestibular portion of the inner ear was invaded but cases of cochlear involvement have been described as well. Twelve cases with pre-operative auditory function preservation despite extensive labyrinthine destruction treated at our Institution are reported. Seven cases retained cochlear function post-operatively. Possible explanations of this occurrence and implications of related with hearing preservation in the presence of widespread inner ear destruction by chronic inflammatory disease are discussed.

Pseudocyst of the auricle. Case report and world literature review

We treated a patient with pseudocyst of the auricle and reviewed the 113 cases previously published in the world literature. Pseudocyst of the auricle is an asymptomatic, noninflammatory cystic swelling that involves the anthelix of the ear, results from an accumulation of fluid within an unlined intracartilaginous cavity, and occurs predominantly in men (93% of patients). Characteristically, only one ear is involved (87% of patients), and the lesion is usually located within the scaphoid or triangular fossa of the anthelix. Previous trauma to the involved ear is uncommon. The diagnosis may be suggested by the clinical features, and analysis of the aspirated cystic fluid and/or histologic examination of a lesional biopsy specimen will confirm the diagnosis. Therapeutic intervention that maintains the architecture of the patient's external ear should be used in the treatment of this benign condition.

Effects of middle ear ventilation on cholesteatoma development in experimental animals

This study was designed to evaluate the effect of middle ear ventilation on cholesteatoma formation following propylene glycol application in experimental animals. Fifteen chinchillas had stainless steel ventilation tubes chronically implanted in their bullae and 60% propylene glycol was subsequently instilled into the middle ear cavities. The animals were kept alive for 4 weeks, during which time the middle ear pressure was monitored tympanometrically and the tubes were frequently inspected to verify patency. Of the 30 ears in the study, 20 (66.6%) developed middle ear cholesteatoma--a rate of occurrence comparable to that found in earlier studies in which middle ear ventilation was not provided. These results indicate that negative middle ear pressure is not a necessary factor for cholesteatoma development following application of chemical irritants in experimental animals.

Homograft tympanoplasty: the Iowa experience

Homograft tympanic membranes have been used in tympanoplasty for nearly 30 years. Reported anatomical success rates vary from 50 to 100 percent. One hundred and one homograft tympanoplasty procedures were performed at the University of Iowa over the 10-year period of July 1978 through June 1988. The anatomical success rate was 76 percent. Hearing results were satisfactory in 86 percent of cases. The homograft tympanic membrane, with or without ossicles, has proven to be a highly satisfactory modality for the reconstruction of the severely ravaged middle ear.

[Epidermal growth factor in cholesteatoma--the first report: the localization in the cholesteatoma tissue]

The localization of epidermal growth factor (EGF) in human cholesteatoma tissue was examined immunohistochemically, using sections of formalin-fixed, paraffin-embedded tissue with avidin-biotin peroxidase complex method. Thirty-three cases of active cholesteatoma which had abundant granulation and debris were studied. Out of 33 cases, EGF was positive in 32 cases (97%) in the epidermis, 30 cases (91%) in the fibroblast, and 21 cases (64%) in the endothelial cells. In 9 cases of inactive cholesteatoma, on the other hand, EGF was positive in 5 cases (56%) in the epidermis, no case in the fibroblast, and a case (11%) in the endothelial cells. Active cholesteatoma had higher immunoreactivity in the epidermis than inactive cholesteatoma. This suggests that the activity of cholesteatoma is indicated by the immunoreactivity of EGF. Difference of EGF immunoreactivity between active and inactive cholesteatoma was bigger in the fibroblast in the subcutaneous tissue of cholesteatoma than in the epidermis. This gives the reason that the activity of cholesteatoma exists in the subcutaneous tissue. These results suggest that EGF plays an important role in accelerating the growth of cholesteatoma.

The spatial organisation of keratinocytes in acquired middle ear cholesteatoma resembles that of external auditory canal skin and pars flaccida

A scanning electron microscopic study of acquired middle ear cholesteatoma was undertaken in order to compare morphological findings with those of keratinising squamous epithelium of the tympanic membrane and external auditory meatus. Analysis of results confirms a highly ordered vertical architecture, with cell stacking, in the stratum corneum of cholesteatoma, similar to that found in the skin of the deep external auditory meatus and the pars flaccida of the tympanic membrane. These findings support the notion that acquired cholesteatoma originates by immigration of epithelium from the pars flaccida and external meatus rather than by metaplasia of middle ear mucosa.

Middle ear as a gas pocket

An analysis of 45 adult ears that underwent a modified radical mastoidectomy for cholesteatoma and remained with an intact unperforated pars tensa is described. 1) While in practically all these ears some air was present behind the tympanic membrane, its amount varied considerably. 2) The air present behind the tympanic membrane was always in communication with the eustachian tube. 3) The regions in the middle ear devoid of air presented a deep atelectasis that was found predominantly in the posterior-superior part of the middle ear. Topographically the regions of air and atelectasis corresponded to the distribution of ciliated and flat epithelia in the middle ear, respectively. The presence of air in the middle ears obliges us to view these ears as being aerated gas pockets. The aeration difference between such an atelectatic ear and one in a physiologic state is probably a difference of degree. This difference can result from reduction in aeration through the eustachian tube or from excessive absorption of gases into the circulation, or from deficient normal diffusion of carbon dioxide or nitrogen from the circulation into the middle ear, or from a combination of these factors. The analogy with the respiratory system is emphasized.

Auricular chondritis in Wistar rats

The macroscopic and microscopic features of auricular chondritis in Wistar rats are described. Histologic lesions are characterized by granulomatous inflammation, chondrolysis, and multinodular proliferative foci. The condition in Wistar rats is compared to auricular chondritis in other strains of rats.

[A case of cholesteatoma extending into the medial petrous bone]

A case of facial nerve palsy caused by cholesteatoma was reported. High-resolution CT was very excellent in delineating the mass extension and bony destruction. The labyrinthine segment of facial canal was thought to be the route of spread of cholesteatoma to the medial petrous bone as this case of poor pneumatized petrous bone.

Cartilaginous pseudocyst of the external auricle in children with atopic eczema

Four children with severe atopic eczema developed painless endochondral pseudocysts of the external auricle. The lesions were bilateral in two cases. In one case the lesion spontaneously resolved; of the remaining five lesions, one contained haematoma and the other four contained serous fluid. The aetiology of these lesions and their association with atopic eczema are unclear, but repeated minor trauma from rubbing may play a part.

Ligneous conjunctivitis with ear involvement

We report the association of ligneous conjunctivitis with middle-ear and tympanic membrane involvement in two children. Eye and ear specimens revealed histopathologic and ultrastructural findings consistent with ligneous conjunctivitis, characterized by an amorphous, eosinophilic material with acute and chronic nongranulomatous inflammation. Ear specimens demonstrated granulation tissue along with the above features. Conjunctival and ear lesions from these patients were studied histochemically, immunohistochemically, and ultrastructurally. Our studies demonstrate fibrin and albumin deposition as a common feature in all lesions. Deposition of other components, such as mucopolysaccharides, amyloid, immunoglobulins, and mast cells, were, however, variable. The diversified nature of these lesions, together with the association of eye and ear disease, substantiates the existence of an underlying systemic disorder of unknown cause.

Amyloidosis of the middle ear in a chronically hemodialyzed patient

We report a 24-year-old woman on chronic hemodialysis for 7 years in whom investigations for an acute hearing loss revealed a serous otitis media. Tissue obtained at bilateral tympanotomy contained amyloid, which proved to be sensitive to potassium permanganate. This finding may indicate that amyloidosis in hemodialyzed patients is more common than initially thought. A brief review of amyloidosis in hemodialyzed patients is given.