Suprameatal triangle

Abstract: Three-dimensional (3D) surface renderings of the temporal bone were created from routine axial computed tomographic (CT) images in 15 subjects and in cadaver specimens. The displayed anatomy was correlated with these specimens, as well as with images from the routine study. Six sets of viewing angles were derived for optimal display of surgically important surface landmarks, such as the suprameatal triangle and supramastoid crest. The 3D CT images were found to be of excellent quality and permitted a global view of the temporal bone surface anatomy. Bone depletion artifacts ("pseudoforamina") posed a potentially serious problem in evaluating the tegmen and wall of the sigmoid sulcus, being present in eight of 20 cases. Three-dimensional CT may be a useful adjunct to routine temporal bone imaging.

Abstract: This article presents a new repositioning method in dystopic microtia (low-set microtia, anteriorly tilted microtia, or both) with the presence of the external auditory canal. In the case of low-set malformations, the dystopic auricular canal complex was freed from adjacent bony structure, shifted upward, and anchored to the thick periosteum of the suprameatal triangle or the adjacent superior portion of the temporal bone with nonabsorbable sutures. When the auricular vestige was large and dystopia was severe, the complex was shifted with attachment of the temporoparietal fascia on its cranial part. Meanwhile, when the auricular vestige was small and dystopia was mild, the complex was shifted without attachment of the temporoparietal fascia. Then, the ear framework fabricated with autogenous costal cartilage was positioned and wrapped with the temporoparietal fascial flap. In the case of anteriorly tilted malformations, the dystopic complex was freed, shifted posteriorly, and anchored to the periosteum of the suprameatal triangle. Preauricular dead space, resulting from shifting the complex, was obliterated with pieces of costal cartilage. Simultaneously, the ear framework was placed and wrapped with the temporoparietal fascial flap. No skin necrosis of the shifted complexes occurred in any of the cases. In one case, the facial nerve was transected during dissection and reanastomosed. Upward repositioning distances in low-set microtias were between 1 and 3.5 cm. Posteriorly repositioning distances in anteriorly tilted microtias were 2 and 3 cm. Thirteen patients with low-set malformations, two patients with anteriorly tilted malformations, and three patients with low-set and anteriorly tilted malformations underwent reconstructive operations. The new repositioning method is relatively simple, safe, and effective.

Abstract: Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was studied on Anatolian skulls. In all, 363 male and 231 female skulls were studied. The most prevalent type of suprameatal spine resembled a crest and was found in both sexes on the right (77.6%) and left (80%) sides. The absence of a suprameatal depression was significantly higher in females (right 9.1%; left 8.7%) than in males (right 1.7%; left 2.5%). Suprameatal depressions were mostly shallow in female subjects, but were mostly observed in males to be at a medium depth or deep.

Abstract: Objective: The aim of this study is to evaluate the use of mastoid process as a tool for sex determination in unidentified skeleton. Methods: Eighty (40 male and 40 female) complete undamaged skulls of known sex in book record were used for the study. Eight different measurements on the right mastoid of each skull were recorded. Measurements were made using vernier calipers (0.01mm). The values were subjected to univariate and multivariate analysis employing SPSS Windows 13.00 version program. Results : Statistics revealed high significance (p<0.000) in five measurements except Asterion porion, Posterior end of incisura mastoidea - depression of suprameatal triangle and Asterion-depression of suprameatal triangle. Direct method with all parameters gave discrimination accuracy of 82.5% and in step wise analysis an accuracy of 65.0%. Stepwise analysis selected Mastoidale Porion as the best discriminant. Conclusion : Reports on the use of mastoid process as a tool for sex estimation in unidentified human skeleton has been reported in different populations. The present study supports this finding among the South Indian population.