introduction: computed tomography (ct) and cone-beam ct (cbct) are valuable diagnostic aids for many clinical applications. this study was designed to compare the gray scale value (gsv) and hounsfield unit (hu) of selected dental materials and various hard tissues using ct or cbct. methods and materials: three samples of all test materials including amalgam (am), composite resin (cr), glass ion...

BACKGROUND The precision in carbon ion radiotherapy depends on the calibration of Hounsfield units (HU) as measured with computed tomography (CT) to water equivalence. This calibration can cause relevant differences between treatment planning and treatment delivery. METHODS Calibration data for several soft tissues were measured repeatedly to assess the accuracy of range calibration. Samples ...

-This paper describes initial results of a 3D field topology analysis for automating colour transfer function design aiming at comprehensible volume rendering. Computed tomography (CT) scanners measure the linear xray radio density attenuation values of body tissues in Hounsfield units (HU). Many alternative colour maps have little additional diagnostic or intuitive value relative to grayscale....

BACKGROUND AND PURPOSE Electrocardiogram-gated 4D-CTA is a promising technique allowing new insight into aneurysm pathophysiology and possibly improving risk prediction of cerebral aneurysms. Due to the extremely small pulsational excursions (<0.1 mm in diameter), exact segmentation of the aneurysms is of critical importance. In vitro examinations have shown improvement of the accuracy of vesse...

In this paper, we investigate the transferability limitations when using deep learning models, for semantic segmentation of pneumonia-infected areas in CT images. The proposed approach adopts a 4 channel input; 3 channels based on Hounsfield scale, plus one (binary) denoting lung area. We used different, publicly available, datasets. If area mask was not model generates proxy image. Experimenta...

Purpose To evaluate the impact of various computed tomography scan-based parameters of renal stones on the outcome of extracorporeal shock wave lithotripsy (ESWL). Materials and Methods We conducted a retrospective study of patients who underwent ESWL for renal stones (sized 5-20 mm) from January 2013 to December 2016. We evaluated body mass index, location of the stone, skin-to-stone distanc...

Aim Bladder ruptures are commonly misdiagnosed as gastrointestinal perforations or intestinal ischemia. If a diagnosis is made preoperatively, conservative treatment is a safe and effective option. We evaluated the validity of using the attenuation value of ascites, measured by non-contrast computed tomography (CT), to identify patients with bladder ruptures. Methods A retrospective search of...

Background and aims. Cone-beam computed tomography (CBCT) is an imaging system which has many advantages over computed tomography (CT). In CT scan, Hounsfield Unit (HU) is proportional to the degree of x-ray attenuation by the tissue. In CBCT, the degree of x-ray attenuation is shown by gray scale (voxel value). The aim of the present study was to investigate the relationship between gray scale...