Comparison of gonadal radiation doses from CT enterography and small-bowel follow-through in pediatric patients.

OBJECTIVE. CT enterography is superior to small-bowel follow-through (SBFT) for diagnosis of inflammatory bowel disease (IBD). It is widely assumed that the radiation dose from CT enterography is greater than that from SBFT in the pediatric patient.

Optimization of kilovoltage and tube current-exposure time product based on abdominal circumference: an oval phantom study for pediatric abdominal CT.

Objective: This CT study evaluates image noise and radiation dose using a modified CT dose index phantom to approximate pediatric abdominal shape. Contrast-to-noise ratio (CNR) and radiation dose were measured.

Materials And Methods: The oval shape was simulated by fixing 1000-mL saline bags aside cylindric phantoms with variable circumferences.

Comparison of indirect radiation dose estimates with directly measured radiation dose for patients and operators during complex endovascular procedures.

Background: A great deal of attention has been directed at the necessity and potential for deleterious outcomes as a result of radiation exposure during diagnostic evaluations and interventional procedures. We embarked on this study in an attempt to accurately determine the amount of radiation exposure given to patients undergoing complex endovascular aortic repair. These measured doses were then correlated with radiation dose estimates provided by the imaging equipment manufacturers that are typically used for documentation and analysis of radiation-induced risk.

Optimization of kVp and mAs for pediatric low-dose simulated abdominal CT: is it best to base parameter selection on object circumference?

Objective: The objective of our study was to determine the effect of mAs and kVp reduction on pediatric phantoms based on patient circumference to optimize dose reduction and maintain image quality for abdominal CT.

Subjects And Methods: Three polymethylmethacrylate right cylindric CT dose index (CTDI) phantoms with diameters of 10, 16, and 32 cm simulated the abdomen of an infant, child, and adolescent, respectively. Using a National Institute of Standards & Technology ion chamber and Victoreen 660 electrometer, doses at centerline were recorded on a 16-MDCT scanner.

Effect of altering automatic exposure control settings and quality reference mAs on radiation dose, image quality, and diagnostic efficacy in MDCT enterography of active inflammatory Crohn's disease.

Objective: The purpose of our study was to determine whether the MDCT enterography dose can be reduced by changing automatic exposure control (AEC) setting and quality reference milliampere-seconds (mAs) without altering subjective image quality or efficacy in active inflammatory Crohn's disease.

Subjects And Methods: This is a prospective study of 2,310 MDCT enterography procedures performed using 16- and 64-MDCT in three cohorts (original, intermediate, and final dose levels). For 16-MDCT, the original and intermediate dose level quality reference mAs was 200, and weight-based (1 pound [0.

CT arthrography: in vitro evaluation of single and dual energy for optimization of technique.

The purpose of this study was to optimize CT arthrography technique and determine if dual energy CT (DECT) can provide any benefit over single energy CT (SECT). Iodinated contrast attenuation at different concentrations was measured using DECT and SECT at different beam energies (140, 120, and 80 kVp). Dose and noise were measured on phantoms at different tube currents.

Rheumatoid arthritis: evaluation with contrast-enhanced CT with digital bone masking.

The purpose of this HIPAA-compliant study was to prospectively evaluate the feasibility of contrast material-enhanced computed tomography (CT) with digital bone masking for the evaluation of synovitis and tenosynovitis in patients with rheumatoid arthritis. Four patients with rheumatoid arthritis and findings at magnetic resonance (MR) imaging were evaluated after informed consent for this institutional review board-approved study was obtained. To improve the conspicuity of synovial enhancement, postcontrast CT was performed with a relatively low kilovoltage and high iodine concentration and precontrast images were used as a subtraction mask to eliminate high-attenuation cortical bone contours.

Imaging characteristics of zinc sulfide shell, cadmium telluride core quantum dots.

Aims: Quantum dots are optical nanocrystals whose in vitro and in vivo use in molecular imaging is expanding rapidly. In comparison with organic fluorophores, quantum dots exhibit desirable properties, such as multiwavelength fluorescence emission, excellent brightness and resistance to photobleaching. Their electron-dense, metallic cores suggest utility in other clinical imaging modalities.

Radiation exposure to the surgeon and the patient during kyphoplasty.

Study Design: Prospective study of patients who underwent single or multilevel kyphoplasty for vertebral fractures.

Objective: To quantify the radiation exposure to the surgeon and to the patient during kyphoplasty, and also to provide a procedural algorithm that effectively minimizes the radiation exposure to the surgeon during any fluoroscopic-guided procedure.

Summary Of Background Data: Spine surgeons who perform minimally invasive procedures often employ fluoroscopy for intraoperative navigation.

Sealing of type III endoleaks with ethylene vinyl alcohol copolymer in a canine model.

Purpose: To test ethylene vinyl alcohol copolymer (EVOH) as a sealing agent for persistent abdominal aortic aneurysm (AAA) endograft leaks.

Materials And Methods: Twelve dogs underwent creation of AAAs with a Palmaz P4014 stent. A 10-mm x 5-cm Wallgraft endoprosthesis with a 4-mm-diameter hole cut into its side was deployed within the AAA.

Diagnostic imaging: radiation dose and patients' concerns.

Exposure to ionizing radiation during diagnostic radiologic procedures carries small but real risks, and children, young adults, and pregnant women are especially vulnerable. Exposure of patients to diagnostic energy levels of ionizing radiation should be kept to the minimum necessary to provide useful clinical information and allay patients' concerns about radiation-related risks.

Selective retention of bone marrow-derived cells to enhance spinal fusion.

Connective tissue progenitors can be concentrated rapidly from fresh bone marrow aspirates using some porous matrices as a surface for cell attachment and selective retention, and for creating a cellular graft that is enriched with respect to the number of progenitor cells. We evaluated the potential value of this method using demineralized cortical bone powder as the matrix. Matrix alone, matrix plus marrow, and matrix enriched with marrow cells were compared in an established canine spinal fusion model.

Spine fusion using cell matrix composites enriched in bone marrow-derived cells.

Bone marrow-derived cells including osteoblastic progenitors can be concentrated rapidly from bone marrow aspirates using the surface of selected implantable matrices for selective cell attachment. Concentration of cells in this way to produce an enriched cellular composite graft improves graft efficacy. The current study was designed to test the hypothesis that the biologic milieu of a bone marrow clot will significantly improve the efficacy of such a graft.