Introdouction: An exact knowledge of the anatomical variations of the paranasal sinuses (PNS) is critical for surgeons performing endoscopic sinus surgery and for radiologists involved in making preoperative evaluations. An important aspect is the determination of correlation between the anatomical variations of PNS and the presence of chronic rhinosinusitis (CR). Cone-beam computed tomograph...

the computational method based on using the operational matrix of anorthogonal function for solving variational problems is computeroriented. in this approach, a truncated hartley series together withthe operational matrix of integration and integration of the crossproduct of two cas vectors are used for finding the solution ofvariational problems. two illustrative examples are included todemon...

internal iliac artery (iia) shows frequent variations in its branching pattern. we saw variations in the branching pattern of right iia in a male cadaver. the iia divided into anterior and posterior divisions. the branches of the anterior division included umbilical artery, inferior vesical artery, obturator artery. the other branches arose from posterior trunk such as iliolumbar, lateral sacra...