The incidence and morphology of maxillary sinus septa in dentate and edentulous maxillae: a cadaveric study with a brief review of the literature

OBJECTIVES: The aim of this study is to determine the incidence, location, and orientation of maxillary sinus septa in formalin embalmed cadavers. MATERIALS AND METHODS: The study was conducted on 210 cadaveric heads available in our department. After taking the mid-sagittal section the specimens were opened from the medial aspect and the sinus cavity was explored for the presence of maxillary sinus septa, their anatomical plane, location and dimensions. RESULTS: The mean linear distance between maxillary sinus floor and its anatomical ostium was 26.76+/-5.21 mm and 26.91+/-4.96 mm on right and left side, respectively. A total of 59 maxillary sinus septa (28.1%) were observed in 210 maxillary specimens. Septae were most common, 33 septa (55.9%), in the middle region (between first and second molar tooth) of the sinus cavity. The maxillary sinus membrane (Schneiderian membrane) adhered tightly to the maxillary sinus and over the septae. Significantly more maxillary sinus septa were observed in edentulous maxillae in comparison to the dentate upper jaw. CONCLUSION: Knowledge of location of maxillary sinus ostium is mandatory for the rhinologist for drainage of secretions in maxillary sinusitis. The morphological details of maxillary sinus septa, particularly their location and anatomical planes, will guide dentists in performance of safe implant surgeries. The maxillary antrum septa of category I and II may complicate the procedure of inversion of bone plate and elevation of sinus membrane during maxillary augmentation surgeries. The category III septa observed in the sagittal plane were embedded by one of the branches of the infraorbital nerve in it, and if accidentally cut will lead to infraorbital nerve palsy in maxillary sinus surgeries.

Morphological variations of papillary muscles in the mitral valve complex in human cadaveric hearts

<p><b>INTRODUCTION</b>Papillary muscle rupture and dysfunction can lead to complications of prolapsed mitral valve and mitral regurgitation. Multiple operative procedures of the papillary muscles, such as resection, repositioning and realignment, are carried out to restore normal physiological function. Therefore, it is important to know both the variations and the normal anatomy of papillary muscles.</p><p><b>METHODS</b>This study was carried out on 116 human cadaveric hearts. The left ventricles were opened along the left border in order to view the papillary muscles. The number, shape, position and pattern of the papillary muscles were observed.</p><p><b>RESULTS</b>In this series, the papillary muscles were mostly found in groups instead of in twos, as is described in standard textbooks. Four different shapes of papillary muscles were identified - conical, broad-apexed, pyramidal and fan-shaped. We also discovered various patterns of papillary muscles.</p><p><b>CONCLUSION</b>No two mitral valve complexes have the same architectural arrangement. Each case seems to be unique. Therefore, it is important for scientists worldwide to study the variations in the mitral valve complex in order to ascertain the reason behind each specific architectural arrangement. This will enable cardiothoracic surgeons to tailor the surgical procedures according to the individual papillary muscle pattern.</p>

Variations of anterior cerebral artery in human cadavers

Background: Anterior cerebral artery is an important terminal branch of internal carotid artery. It forms the anterior component of circle of Willis along with the anterior communicating artery. Circle of Willis is known for the frequent variations. The knowledge of anatomical variations in anterior cerebral artery is of considerable help to clinicians. Method: Morphology and variations of the anterior cerebral arteries and the anterior communicating artery were studied in 112 formalin preserved brain. Results: Variations were found in 31.3% (n=35). Variations of the segments in relation with size, course, communications and terminations of the anterior cerebral artery (ACA) were noted. These were divided into different groups like hypoplasia, aplasia, duplication and fenestrations. The mean diameter and length of the proximal segment of the anterior cerebral artery (A1) was 3.2 mm and 15.7 mm, anterior communicating artery (ACoA) was 2.4 mm and 3.3 mm and distal segment of the anterior cerebral artery (A2) was 2.5 mm and 42.1 mm respectively. Conclusion: Variation of anterior cerebral artery is common in this study of Indian human cadavers.