Association of the superior semicircular canal and tegmen tympani dehiscences and its relationship with the pneumatisation of the temporal bone.

PURPOSE: To analyse the degree of pneumatisation of the temporal bone when there is an association between dehiscence of the superior semicircular canal and dehiscence of the tegmen tympani. MATERIALS AND METHODS: We analysed a retrospective CT study of 124 selected cases. A single inclusion criterion was applied: the presence of a dehiscence of the tegmen tympani. On the other hand, the degree of temporal pneumatisation was assessed by axial and coronal planes, and has been divided into the following grades O, I, II and III, according to the status and relationship of the mastoid, the bony labyrinth, the petrous segment of the carotid canal and sigmoid sinus. RESULTS: Of the 124 cases studied, 35 (28.2%) presented both dehiscences. In 26 of the 35 (47.3%), grade II pneumatisation, 4 (14,8%), grade I, and 5 (11,9%) grade III was observed, with a statistically significant relationship (p < 0.001). On the other hand, we did not find a significant relationship when relating both dehiscences in any age or sex group. However, when relating the degree of pneumatisation to sex, among those with grade III pneumatisation, the proportion of men (52.4%) was significantly higher than that of women (47.6%) (p = 0.017). CONCLUSION: We have detected a statistically significant relationship between the coexistence of grade II pneumatisation and the presence of both dehiscences in the temporal bone.

[Peculiarities of the parietal organisation of the superficial temporal artery]. / Peculiaridades de la organización parietal de la arteria temporal superficial.

INTRODUCTION: The study of the structure in the arterial wall has been essential to use vessels in the coronary and cerebral bypass. The superficial temporal artery, owing to its high elastic content and its topography, close to the middle cerebral artery, has made possible the revascularization surgery in cerebral areas with ischemia. AIM. The purpose of this study is define the structure of the superficial temporal artery. MATERIAL AND METHODS: The material of the present study are 60 arteries from medico legal necropsies without apparent vascular pathology. Pieces were fixed in 10% formol, embedded in Paraplast, sectioned in sequence of 7 mm and were stained to detect elastic, collagen and reticulin fibers. Histochemical techniques have been done too. RESULTS: The superficial temporal artery shows a high elastic content, above all in the middle outer of the tunica media. The negative aspect is the great quantity of collagen in this tunica, that produces the progressive hardness of this vessel with the increase of the age. Histochemistry shows how the accumulation of acid mucosubstances interferes in the correct nourishing of the internal elastic membrane, that is disorganized in the cushions. CONCLUSION: The superficial temporal artery is an appropriate vessel to the coronary and cerebral bypass, due to its high elastic content in this tunica and the limitants. It have not been observed in our material zones without internal elastic membrane. Histochemistry shows abundant acid mucosubstances that difficult the nourishing in the arterial wall.