نتایج جستجو برای: cone beam
تعداد نتایج: 145331 فیلتر نتایج به سال:
abstract deep seated cavernous angioma (ca) is a very rare entity, those occurring in the hypothalamus are still less common. we present a case of a 52-year-old man who presented with behavior and memory disturbance attacks. he had a ca of the hypothalamus as revealed by magnetic resonance imaging (mri). we will discuss the role and importance of imaging in such scenario and also the differenti...
neurofibroma is an autosomal dominant disorder which has major criteria such as hyperpigmentation (cafe-au lait spots), cutaneous and subcutaneous tumors and bone deformities. in this report, a case of multifocal intraosseous neurofibroma in a 16-year-old male with right facial asymmetry, multiple unerupted maxillary posterior teeth and a previous history of infratemporal and orbital neurofibro...
مقدمه: آگاهی از موقعیت دقیق کف سینوس ماگزیلا در تعیین مکان ایمن جهت اقدام جراحی و گذاشتن ایمپلنت عاملی بسیار مهم می باشد. هدف از این مطالعه مقایسه فاصله لبه کرست تا کف سینوس ماگزیلا در سه نمای سه بعدی، کراس سکشنال و پانوراما از تصاویر cone beam computed tomography (cbct) بود. مواد و روش ها: در این مطالعه توصیفی- تحلیلی تعداد 94 تصویر cbct تهیه شده با دستگاه galileos با روش نمونه گیری آسان انتخا...
a 20-year-old man presented with the history of pain and swelling in the anterior maxillary segment. the periapical radiography was indicative of a dental anomaly in right maxillary lateral incisor. due to the insufficient information from conventional radiography, cone-beam computed tomography (cbct) was ordered. cbct showed apical root resorption, large apical lucency and two separate canals ...
i ntroduction: vertical root fracture (vrf) is the longitudinal fracture of the root in endodontically treated teeth. considering the limitations of two-dimensional radiographic images in detection of vrf and introduction of cone-beam computed tomography (cbct), this study was designed to find the sensitivity, specificity and accuracy of cbct and periapical (pa) radiography in detection of vrfs...
BACKGROUND AND PURPOSE The development of flat panel detectors (FPDs) has made cone-beam CT feasible for practical use in a clinical setting. Our purpose was to assess the usefulness of cone-beam CT using the FPD in conjunction with conventional digital subtraction angiography (DSA) for performing superselective intra-arterial chemotherapy for head and neck tumors. MATERIALS AND METHODS Twent...
Most of the treatment units, both new and old models, are equipped with a megavoltage portal imager but its use for volumetric imaging is limited. This is mainly due to the poor image quality produced by the high-energy treatment beam (> 6MV). A linac at our center is equipped with a prototype 2.5 MV imaging beam. This study evaluates the feasibility of low-dose megavoltage cone-beam imaging wi...
Abstract Cone-beam computed tomography (CT) with circular scanning trajectory is known to suffer from so called cone-beam artifacts. Cone-beam artifacts are errors in the reconstructed volume due to incomplete radon data. These artifacts increase with increasing distance of the reconstructed plane from the midplane, i.e. the plane containing the X-ray source. Theoretically, the midplane represe...
Cone beam CT, usually used in dental area, could easily obtain 3-dimensional images using cone beam shaped ionized radiation. Cone beam CT is very useful for direct percutaneous sac injection (DPSI) which needs very precise measurement to avoid puncture of inferior vena cava or vessel around sac or stent graft. Here we describe two cases of DPSI using cone beam CT. In case 1, a 79-year-old male...
A filtered backprojection reconstruction algorithm was developed for cardiac single photon emission computed tomography with cone-beam geometry. The algorithm reconstructs cone-beam projections collected from ;short scan' acquisitions of a detector traversing a noncircular planar orbit. Since the algorithm does not correct for photon attenuation, it is designed to reconstruct data collected ove...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید