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OBJECTIVES: To establish a new surgically relevant classification system of the anatomic variations of the temporal bone tegmen plate as well as to perform a comparative analysis, with respect to the pneumatization patterns in the cadaveric temporal bones. MATERIALS AND METHODS: Microdissection of the human cadaveric temporal bones was performed after obtaining ethical approval from the Institutional Ethical Committee (F.8-522/A-522/2017/RS). The pneumatization pattern of the temporal bones was noted as "under-pneumatized" or "well-pneumatized." The tegmen mastoid (TM) was classified into two grades as per the position of the tegmen plate and the visibility of the superior semicircular canal (SSCC) and the aditus. The latter two structures were well visualized in Grade A and poorly visualized in Grade B. The data were analyzed using Stata 14.0 (Stata Corp, 4905, Lakway drive, College Station, Texas, USA). RESULTS: Ninety-three temporal bones were dissected under microscope. Fifty-eight bones were well-pneumatized and 35 were under-pneumatized. The tegmen plates were classified as Grade-A in 49 bones (well-pneumatized -37 and under-pneumatized -12), and as Grade-B in 44 bones (well-pneumatized-21, poorly-pneumatized-23). Grade-A classification was significantly more common in well-pneumatized temporal bones, while Grade-B was more common in under-pneumatized bones (p=0.0057). CONCLUSION: We propose a surgically relevant classification for TM positioning. A well-pneumatized temporal bone is associated with a significantly higher position of the tegmen plate (Grade-A TM).

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Infections with nontuberculous mycobacteria (NTM) are being identified with increasing frequency, but the otologic manifestations of NTM infection are not well defined. Mycobacterium abscessus is a ubiquitous rapidly growing mycobacterium (RGM) known to cause disease by inoculation after trauma. Though reported following open heart and breast augmentation surgery, it is not recognized as a cause of sporadic post-tympanostomy tube otorrhea. This report presents detailed clinical information on six sporadic cases and partial information on 15 additional cases of ear infection caused by RGM over the past 7 years. Of these, 20 of 21 cases (95%) were attributable to M. abscessus, 14 of 21 (67%) subjects lived in a southern coastal state and 16 of 16 with available histories had previously undergone placement of tympanostomy tubes. Each isolate exhibited resistance to many antibiotics, with 50 percent exhibiting high level mutational resistance to aminoglycosides related to prior topical aminoglycoside use. Therapy was difficult, requiring debridement and prolonged antibiotic therapy. M. abscessus is a problematic infection requiring specific diagnosis and treatment and should be sought as a cause of refractory post-tympanostomy tube otorrhea.

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Following our previous experimental studies on the performance of macroporous biphasic calcium phosphate (MBCP) in canine mastoid cavities, we used this material in patients requiring surgical intervention. Twenty-two cases were selected, and in eight specific cases a biopsy specimen was taken. Histologic, ultrastructural, and microanalysis studies were performed. This study demonstrates the effectiveness of MBCP implants as bone graft substitutes for mastoid cavity obliteration. Clinical evaluation of the series and histologic and ultrastructural results demonstrated the bioactivity and osteo-conduction of this material, with partial transformation of MBCP granules into lamellar bone after several months.

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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.

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Physiological changes in body position affect the degree of opening and closing of human auditory tubes. Notable changes were observed in lateral body position concerning the opening rate of the auditory tubes, which corresponds to the changes in pressure within the lower portion of the middle ear cavity. This physiological mechanism seems to be related with the anatomical direction of the auditory tube and the natural mechanism for the protection of the middle ear cavity. When a change takes place which moves the compliance of the eardrum to the positive side (e.g. head position change or static lateral body position), observation suggests the possibility of venostatis and production of gas. Measurement of the oxygen tension in the middle ear cavity under atmospheric pressure revealed the existence of constant gas production which maintains the pressure in the middle ear cavity at the same level as atmospheric pressure. This result denies the influx of gas from the atmospheric environment into the middle ear cavity. These results stem from the intrinsic physiologic mechanism of the middle ear cavity, namely maintenance of effective auditory sound conduction (a function to keep eardrum compliance as close to zero as possible), by keeping the pressure within the middle ear cavity below the atmospheric pressure, either at the same level as or slightly higher than that of the environment pressure. Gas emission from the middle ear cavity in the atmospheric environment and a low oxygen tension are a natural physiologic mechanism to protect the middle ear cavity from infection and other hazards.

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The pathologic changes of the middle ear and mastoid bone mucosa in two pediatric patients with long standing chronic serous otitis media were studied by electron and light microscopy. The embryological development of the eustachian tube, middle ear cleft, and mastoid bone suggests a common physiological and anatomical continuity. The histological changes by light and electron microscopy in these patients demonstrates the metaplastic changes of the basal cell of the mucosa differentiating into mucous and keratin cells. These metaplastic changes are associated with the exudative process known as chronic serous otitis media.

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Light- and electron microscopic studies of recent years have definitely concluded that the epithelium of the middle ear is a modified respiratory epithelium with ciliated and secretory cells including goblet cells. Goblet cells are secretory cells completely filled with secretory granules. Secretory cells and ciliated cells are both derived from the basal cell. The subepithelial layer which consists of loose connective tissue is a structure of just as great importance as the epithelial layer. It is still not clear whether the dark granulated cell is the site of production of the serous middle ear effusion or whether it merely represents an immature stage of the mucigen-producing cell.

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Granulocytic sarcoma (chloroma) is a localized tumefaction of immature granulocytes that is typically seen in association with myelogenous leukemia. The primitive cell population seen in biopsy material may be misinterpreted as histiocytic lymphoma or other sarcoma unless additional studies are performed. We saw a 36-year-old woman with promyelocytic leukemia in remission who had the signs and symptoms of an acute coalescent mastoiditis. Histologic examination of the surgical specimen, however, demonstrated a granulocytic sarcoma. Our case exemplifies some of the difficulties that may be encountered in the diagnosis of granulocytic sarcoma and illustrates the point that symptoms of an inflammatory process in a patient with a diagnosis of leukemia must be regarded with a degree of suspicion.

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This paper deals with the surgical approaches to that part of the intratemporal facial nerve lying proximal to the cochleariform process and focuses on two issues: the advisability of disarticulating the ossicular chain to reach this area and the accessibility of the labyrinthine segment via the transmastoid, extralabyrinthine, subtemporal route. Relevant anatomical features, which are based on 39 gross temporal bones, 47 histologic sections, and 10 cadaveric specimens are first considered. In the head specimens, it was possible to attempt exploration of the entire nerve with the transmastoid, extralabyrinthine, subtemporal operation and then remove the labyrinth to gauge the adequacy of this approach as an avenue to the labyrinthine segment. These anatomical findings, their bearing on the questions at hand, and the author's clinical experience are incorporated into descriptions of the operations currently in vogue for exploring the proximal nerve in patients with Bell's palsy.

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In a histochemical and ultrastructural study the pathogenesis of cholesteatoma ostitis is analysed on human tissue. In the subepithelial layer there is evidence of an inflammatory reaction leading to proliferation of granulation tissue with bony invasion. Bony destruction is initiated by osteocytic osteolysis. In the case of cholesteatoma there is a combined action of extraosseous and osseous lysosomal enzymes. The pathological changes of the fibrillar elements suggest that the self-perpetuation of degeneration is maintained by a disturbance of fibrillogenesis. The causal pathogenesis of cholesteatoma formation is discussed as a function of a disturbance between cellular activity, extracellular matrix, and cellular surface.

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The clinical picture of otitis nigra (idiopathic sero-hemmorrhagic otitis media) as independent clinical entity is shown, presenting 5 cases requiring mastoid surgery. Samples of mastoid mucosa were investigated by light- and electron-microscopy employing histochemical, immunofluorescent and virological techniques. Pathological changes of the small vessels in the subepithelial connective tissue with increased vascular permeability and extravasation of red blood cells and serum play a central role in the pathogenetic course of the disease. Disintegration of erythrocytes leads by catabolism of hemoglobin to formation of hemosiderin and ferretin, whereas by processing of phospholipids of the cell-membrane cholesterin cristals are deposited in the connective tissue. These cholesterin deposits in turn induce a foreign body reaction with formation of typical cholesterol granulomas. The mucosa shows secretory activity in intraepithelial secretory cells and glandlike structures in the subepithelial connective tissue. Neutral and acidic mucopolysaccharides are demonstrated in the secretory product. As possible cause for the vascular lesion that in turn sets off the pathomechanisme of otitis nigra a subclinical viral infection is discussed. This conjecture is supported by demonstration of virus-like inclusion bodies in macrophages and fibrocytes and of virus-like particles in antral smears. In addition myxoviruses of the parotitis-epidemica group could be identified in these smears by serological methods. Furthermore, the stimulation of the local immunological defense system, evidenced by the presence of numerous immunoglobulin-producing plasmacells in the tissue, is in concord with a viral infection. Therapy requires mastoidectomy in combination with posterior tympanotomy in order to eradicate completely the intractably diseased mastoid mucosa.

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