diagnosis of corneal diseases is possible by measuring and evaluation of corneal thickness in different layers. thus, the need for precise segmentation of corneal layer boundaries is inevitable. obviously, manual segmentation is time‑consuming and imprecise. in this paper, the gaussian mixture model (gmm) is used for automatic segmentation of three clinically important corneal boundaries on opt...

background: the purpose of this study was to evaluate the infl uence of ejection fraction (ef) on peak aortic time (pat) and  peak aortic enhancement (pae) during coronary computed tomography angiography (cta). materials and methods: one-hundred and twenty patients (64 men, 56 women) underwent measurement of coronary cta with a measurement of ef within 3 months of coronary cta.pearson’s correla...

introduction : to evaluate the efficacy of niti mechanical rotary instrumentation and hedstrom file for gutta-percha/sealer removal computed tomography (ct) was utilized in vitro . materials and methods: thirty extracted human single rooted teeth, each with a single canal were selected. the samples were decoronated with a double faced diamond disk to have 17-mm root; teeth roots were instrument...

abstract: cone-beam computed tomography (cbct) has been accepted as a useful tool for diagnosis and treatment in endodontics. despite a growing trend toward using cbct in endodontic practice the cbct images should be interpreted carefully. this case report presents a case that showed radiolucency inside and around a tooth which was free of pathologic changes under a dental operative microscope ...

introduction: this study aimed to perform a rigorous sample standardization and also evaluate the preparation of mesiobuccal (mb) root canals of maxillary molars with severe curvatures using two single-file engine-driven systems (waveone with reciprocating motion and oneshape with rotary movement), using micro-computed tomography (micro-ct). methods and materials: ten mb roots with single canal...

introduction: the aim of the present in vitro study was to compare the accuracy of cone-beam computed tomography (cbct) in determining root canal morphology of mandibular first molars in comparison with staining and clearing technique. methods and materials: cbct images were taken from 96 extracted human mandibular first molars and the teeth were then evaluated based on vertucci’s classificatio...

conclusion this study has highlighted the anatomical variations of npc regarding its dimension, location and morphological appearance. cylindrical was the most common shape followed by funnel-shape, hourglass, and spindle, which were the other canal shapes with less frequency, respectively. the results suggest significant relationship between npc, and gender and dental status. the influence of ...

contralateral pneumothorax crossing the midline in a patient with autopneumonectomy can mimic bilateral pneumothoraces on chest radiography. in this study, we report a rare case of right pneumothorax mimicking bilateral pneumothoraces in a patient with left autopneumonectomy. a 37-year-old man complained of progressive chest pain and dyspnea. the initial chest radiography revealed visible visce...

conclusions our study shows in terms of figures that measurements of features of the temporal bone made from spiral ct scan images and those directly obtained during surgery are similar to an adequate extent. results twenty cases were included. in the three measurements performed in this study, only the first parameter (distance between the canal and the sigmoid sinus) was significantly differe...

to our knowledge, bilateral supernumerary kidney is a very rare renal abnormality and there are five cases presented in the literature. it is difficult to diagnose supernumerary kidney and clinicians have not detected most cases preoperatively. laboratory and imaging studies were acquired and carefully examined. the normal laboratory tests were found. emergency ultrasonography was performed and...