use of non ceramic hydroxyapatite in mastoid cavity obliteration and posterior canal wall reconstruction

Despite the higher security [concerning cholesteatoma recurrence using the open cavity procedure, yet such technique represents some disadvantages including: lifelong care for the cavity, often discharging granulations, and vestibular vertigo due to the lack of labyrinthine protection. Most of these disadvantages can be avoided by mastoid cavity obliteration, which involves different materials described in literature. In this study we used non ceramic bioactive Hydroxyapatite micro granules [Osteo Graf / LD-300] with polycaboxylic acid to form a paste for mastoid cavity obliteration. In addition, we placed a conchal cartilage graft to replace the deep part of posterior canal wall, which acted as a support for the filling material and separated the middle ear cavity from the obliterated attic. Also temporal fascia grafting to repair the tympanic memberane was done. Such technique helped in a later second ossiculoplasty procedure to improve hearing in such patients. Our technique was assessed for its validity to obtain a permanent stable bony mastoid obliteration and secondary hearing gain reconstructive procedures; our assessment was clinical, radiological, and audiological. Our use of bony obliteration. The latter statement is true, as only expensive serial contrast enhanced MRI studies are needed for the detection of such recurrence when soft tissue is used for mastoid cavity obliteration

X-Ray energy dispersive analysis and scanning electron microscopic study of normal and otosclerotic stapes with associated middle ear mucosa

A thorough description of ultrastructure of the normal stapes was required to determine changes associated with disease processes. In this work, the morphological appearance and mineral composition of normal and otosclerotic stapes were studied. In addition to the x-ray diffraction and x-ray micro-analysis, these methods allowed us to compare not only the morphology but also the mineral distribution in normal bone with that of otosclerotic lesions in order to gain some new insights into the disease process.12 human specimens [including the stapes with its associated mucosa] were studied. Six of them were normal fresh frozen, while the remaining were otosclerotic ones. The specimens were examined and photographed with Philips Scanning Electron Microscopy XL 3 at 30 kv. Also X-ray energy dispersive micro-analysis was performed with EDAX New XL-30 Zaphire equipment. In examination of the normal stapes, the surface architectural appearance of the human stapes appeared to have four different types of distinct patterns in all the specimens namely; honeycomb, fibrillar, dense and pitted. In the scanning electron microscope of the otosclerotic one, the four types' architectural appearance was not evident. There were two clearly differentiated zones corresponding to apparently normal bone and otosclerotic foci, with clear line of demarcation separating them. The apparently normal bone showed only a fibrillar structure with an irregular trabecular diagram on which rounded expansions were seen. However, in the otosclerotic plate zone even the fibrillar aspect disappeared. Disorganized collagen fibers surrounding holes with incomplete walls were seen. Next to the holes, there were patches of neo-bone formation appeared as abnormal irregular deposited Ca compounds, which seemed to be formed of irregular hydroxyl apatite crystals and rounded Ca deposits. Moreover, the analytic data of the otosclerotic stapes reflected lesser mineral components also the Ca/P ratio of the otosclerotic bone was [1.7] less then that of the normal bone [1.87]. That, perhaps might be attributed not only to the poor mineralization, but also to a changed mineral composition most probably, transformation of apatite into another calcium phosphate crystals. As regards the mucosal changes, this study revealed apparently marked decrease in the ciliated cells and multiple ulcers with loss of epithelial cells in otosclerotic specimens, which might be secondary to the capillary obstruction that also might be proved also by decrease in oxygen content found in the microanalysis technique. The gross morphology and transmission electron microscope did not clearly differentiate between the normal and the otosclerotic stapes, yet the scanning electron microscope and X ray microanalysis described many changes between them that might help clarifying some of the pathogenesis of otosclerosis

role of MMP2 and nm23H1 in predicting the aggressiveness and lymph node metastasis in laryngeal carcinoma

we examined the degree of expression of both MMP2 and nm23 H1 proteins in 24 cases with primary laryngeal carcinoma using immunohistochemistry and correlated the results with the clinical, radiological and histopathological data, in order to evaluate their role in predicting the local spread and/or lymph node status. Preoperative clinical evaluation of these patients included; a full history taking, thorough ENT and neck examination and direct laryngoscopy. Radiological assessment via CT neck thin axial cuts was done. Then laryngeal and nodal specimens were examined histopathologically and immunohistochemically for nm 23H1 and for MMP2 proteins. There was a significant correlation between MMP2 expression and the site of the tumor since much lowering of MMP2 was mainly associated with glottic carcinoma [P<0.05]. Concerning the tumor stage, advanced tumor stages were associated with increase in MMP2 expression, yet it didn't reach statistical significance [P0.07]. However, the presence of lymph node metastasis was significantly related to excess expression of MMP2 [P<0.05]. As regard nm23Hl, a statistically significant correlation was found between nm3H1 expression and tumor stage [P< 0.05]. Moreover, the presence of lymph node metastasis was significantly correlated to the loss of nm23H 1 expression and vice versa [P<0.05]. But correlating the expression levels of MMP2 and nm 23H1, it was statistically insignificant [P >0.05]. Although MMP2 and nm23Hl were correlated to the aggressiveness of malignancy, yet the statistical correlation of their expression levels were statistically insignificant [P >0.05]. Collectively, MMP2 increased expression was related to the occurrence of nodal metastasis of the tumor and also to the tumor sites characterized by frequent metastasis [supraglottic and transglottic]. On the contrary, nm23Hl expression was inversely related to the advancement of tumor stage and the nodal metastatic state