background: the aim of this study is to evaluate the geometry of the distal femur and the proximal tibia in the osteoarthritic knee using 3d reconstructive ct scan imaging. methods: 449 patients with knee osteoarthritis were treated surgically in our center with patient-specific technology total knee arthroplasty. preoperatively, all the patients underwent a ct scan according to a standard prot...

introduction: nowadays virtual colonoscopy has become a reliable and efficient method of detecting primary stages of colon cancer such as polyp detection. one of the most important and crucial stages of virtual colonoscopy is colon segmentation because an incorrect segmentation may lead to a misdiagnosis.  materials and methods: in this work, a hybrid method based on geometric deformable models...

introduction: mandibular fracture is the most common facial bone fracture due to facial trauma. a variety of imagings have been used for diagnosis of mandibular fractures. however, the choice of imaging for diagnosis of mandibular fractures is controversial.present study compares the accuracy of the three most common imaging methods in mandibular fracture diagnosis panoramic radiography, corona...

Letournal and Judet classification of acetabular fracture is widely used. The classification is based on the identification of fracture lines on plain radiographs. Three-dimensional CT scan was claimed to give a better view of the fracture line. Our study showed that intraobserver reproducibility and interobserver reliability were almost the same when classification was done by using plain radi...

ct image quality has been affected by many factors such as kvp, ma, exposure time, alogorithm and section thickness. gantry tilt has the main role in visualization of the temporal bone anatomic structures. in this study, we tried to optimize these factors to determine the best gantry tilt. this study was performed on the human skull phantom and then extended to 15 patients. the phantom was made...

Background: In intensity modulated radiation therapy, cone beam computed tomography (CT) has been used to evaluate patients prior to treatment. This study conducted a comparative evaluation of the image reconstruction ability of the clinically used half-fan bowtie filter and the full-fan bowtie filter. Materals and Methods: A CT simulation marker was inserted inside a human phantom, and the pel...

the presence of anatomic variations of paranasal sinuses must be noted in order to attain a full understanding and accurate diagnosis of chronic sinusitis. the frequency of anatomic variations in chronic sinusitis is different in various studies. the purpose of this study is to assess the frequency of anatomic variations in chronic sinusitis patients admitted to otolaryngology ward of shahid sa...