Global registration of kidneys in 3D ultrasound and CT images.

Purpose: Automatic registration between abdominal ultrasound (US) and computed tomography (CT) images is needed to enhance interventional guidance of renal procedures, but it remains an open research challenge. We propose a novel method that doesn't require an initial registration estimate (a global method) and also handles registration ambiguity caused by the organ's natural symmetry. Combined with a registration refinement algorithm, this method achieves robust and accurate kidney registration while avoiding manual initialization.

Vascular renal anatomy and the ureteropelvic junction: preoperative multidetector CT scanning with split-bolus injection as a predictor of laparoscopic findings.

Purpose: To compare multidetector CT scan (MDCT) results with intraoperative findings in the detection of an inferior-pole pedicle crossing the ureteropelvic junction.

Patients And Methods: Over the 2-year study period, 35 patients receiving laparoscopic pyeloplasty underwent preoperative investigation with a novel MDCT protocol in order to detect crossing vessels. Postprocessing, including maximum intensity projection, volume-rendering technique, and multiplanar reconstruction, was used in addition to standard axial views.

Characterization of human renal stones with MDCT: advantage of dual energy and limitations due to respiratory motion.

Objective: Our aim was to determine, using CT attenuation values, the chemical composition of 241 human renal stones placed in a jelly phantom and to analyze the influence of respiratory motion on the classification.

Materials And Methods: The stones were placed in a jelly simulating the X-ray attenuation of the kidneys. A dynamic platform was used to apply to the phantom free-breathing motion (sinusoidal motion in z-axis) and motion due to lack of maintenance of a breath-hold (5 mm x s(-1) in z-axis).

Efficiency of MR imaging to orientate surgical treatment of posterior deep pelvic endometriosis.

Objective: The purpose of this retrospective study was to evaluate the accuracy of MRI using pelvic-phased-array and endocavitary coils in detecting intestinal wall invasion by an endometriotic nodule.

Materials And Methods: Forty-seven patients (32.1 +/- 4.

Degradation of the z- resolution due to a longitudinal motion with a 64-channel CT scanner.

Isotropic acquisitions are routinely achievable with 64- channel CT scanners,. As it predecessors, it includes MultiPlanar Reformation (MPR) projection for the reconstruction of two-dimensional images and volume rendering for the creation of three dimensional images. The accuracy of images obtained with these postprocessing methods depends on the spatial resolution of image data acquired along the long axis of the patient (ie longitudinal, or z-inis spatial resolution).

Influence of a longitudinal motion on image quality with a 64-channel CT scanner.

Physiologic motions can appear during a Computed Tomography (CT) exam. Even if some motions can be prevented, others are unavoidable. To tempt to correct the resulting artifacts, it is necessary to understand their apparition and their influence on the image quality.

Accuracy of intermediate dose of furosemide injection to improve multidetector row CT urography.

Objective: Evaluate the usefulness of intermediate dose furosemide to improve visualization of the intrarenal collecting system and ureter using MDCTU.

Materials And Methods: Two groups of 100 patients without urinary tract disease or major abdominal pathology underwent MDCTU. Group I (various abdominal indications) was performed without any additional preparation and Group II (suspicion of urinary tract disease) 10 min after injection of furosemide (20mg).

MR Imaging of papillary renal neoplasms: potential application for characterization of small renal masses.

The purpose of our study was to evaluate the role of MRI in demonstrating the precise nature of papillary renal tumors (P RCC) and its potential application to select patients for partial surgery. Ninety-seven tumors less than or equal to 3 cm in size [55 papillary renal cell carcinoma - 42 clear cell renal carcinoma (CC RCC)] were preoperatively evaluated by MRI. Imaging findings were assessed with a special focus on the aspect of the tumoral process.