Examinations of mechanical, and shielding properties of CeO2 reinforced B2O3-ZnF2-Er2O3-ZnO glasses for gamma-ray shield and neutron applications.

The glass system 75B2O3 - 4.5ZnF2 - 0.5 Er2O3- ( 20 - x ) ZnO- x CeO2, x = (0 ≤  x  ≤ 1 mol. %) was manufactured using a melt quenching process, with CeO2 substituted for ZnO in the glass matrix in concentrations ranging from 0 to 1 mol %. The Makishima-Mackenzie model and sound wave velocity measurements were used to evaluate the mechanical parameters and elastic characteristics of the examined glass system, respectively. The results showed that increasing CeO2 doping ratio from 0 to 1 mol% increased density, sound velocities, elastic properties, and microhardness from 5.80 to 9.01 GPa. Phy-X/PSD software was employed to assess the effect of replacing ZnO with CeO2 on shielding capacity. The obtained results revealed that replacing ZnO with CeO2 enhances shielding characteristics and the manufactured glass may be useful in shielding applications.

256 Slice Multi-detector Computed Tomography Thoracic Aorta Computed Tomography Angiography: Improved Luminal Opacification Using a Patient-Specific Contrast Protocol and Caudocranial Scan Acquisition.

CLINICAL RELEVANCE STATEMENT: Caudocranial scan direction and contrast injection timing based on measured patient vessel dynamics can significantly improve arterial and aneurysmal opacification and reduce both contrast and radiation dose in the assessment of thoracic aortic aneurysms (TAA) using helical thoracic computed tomography angiography (CTA). OBJECTIVES: To investigate opacification of the thoracic aorta and TAA using a caudocranial scan direction and a patient-specific contrast protocol. MATERIALS AND METHODS: Thoracic aortic CTA was performed in 160 consecutive patients with suspected TAA using a 256-slice computed tomography scanner and a dual barrel contrast injector. Patients were subjected in equal numbers to one of two contrast protocols. Patient age and sex were equally distributed across both groups. Protocol A, the department's standard protocol, consisted of a craniocaudal scan direction with 100 mL of contrast, intravenously injected at a flow rate of 4.5 mL/s. Protocol B involved a caudocranial scan direction and a novel contrast formula based on patient cardiovascular dynamics, followed by 100 mL of saline at 4.5 mL/s. Each scan acquisition comprised of 120 kVp, 200 mA with modulation, temporal resolution 0.27 seconds, and pitch 0.889:1. The dose length product was measured between each protocol and data generated were compared using Mann-Whitney U nonparametric statistics. Receiver operating characteristic analysis, visual grading characteristic (VGC), and κ analyses were performed. RESULTS: Mean opacification in the thoracic aorta and aneurysm measured was 24 % and 55%, respectively. The mean contrast volume was significantly lower in protocol B (73 ± 10 mL) compared with A (100 ± 1 mL) (P<0.001). The contrast-to-noise ratio demonstrated significant differences between the protocols (protocol A, 18.2 ± 12.9; protocol B, 29.7 ± 0.61; P < 0.003). Mean effective dose in protocol B (2.6 ± 0.4 mSv) was reduced by 19% compared with A (3.2 ± 0.8 mSv) (P < 0.004). Aneurysmal detectability demonstrated significant increases by receiver operating characteristic and visual grading characteristic analysis for protocol B compared with A (P < 0.02), and reader agreement increased from poor to excellent. CONCLUSIONS: Significant increase in the visualization of TAAs following a caudocranial scan direction during helical thoracic CTA can be achieved using low-contrast volume based on patient-specific contrast formula.

Contrast Media Delivery in the Assessment of Anomalous Left Coronary Artery From the Pulmonary Artery.

BACKGROUND: A patient with a history of mitral valve prolapse and regurgitation that was corrected with a mitral ring repair 15 years earlier received a diagnosis of anomalous left coronary artery arising from the pulmonary artery and underwent repair. DISCUSSION: Coronary computed tomography angiography (CTA) was employed to image the patient before surgical intervention. Synchronizing contrast media administration to opacify the right coronary artery in the arterial phase and the left coronary artery in the venous phase required a test-bolus approach. CONCLUSION: Matching compromised cardiovascular dynamics with patient-specific contrast media administration protocols was improved considerably with the use of a test-bolus technique during electrocardiography-gated coronary CTA.

Neurocysticercosis: A case report and brief review.

Neurocysticercosis (NCC) is one of the seven neglected endemic zoonoses targeted by the World Health Organization. It is considered a common infection of the nervous system caused by the Taenia solium and is known to be the primary cause of preventable epilepsy in many developing countries. NCC is commonly resulted by the ingestion of Taenia solium eggs after consuming undercooked pork, or contaminated water. The parasite can grow in the brain and spinal cord within the nervous system, causing severe headache and seizures beside other pathological manifestations. Immigration and international travel to endemic countries has made this disease common in the United States. NCC can be diagnosed with computed tomography and magnetic resonance imaging of the brain. The treatment of the NCC including cysticidal drugs (e.g., albendazole and praziquantel), and neurosurgical procedure, depending upon the situation. A patient of Asian origin came to our clinic with complaints of dizziness, headaches and episodes seizures for the past twelve years without proper diagnosis. The computed tomography and magnetic resonance imaging scans indicated multilobulated cystic mass in the brain with the suspicion of neurocysticercosis.

Contrast medium administration and image acquisition parameters in renal CT angiography: what radiologists need to know.

Over the last decade, exponential advances in computed tomography (CT) technology have resulted in improved spatial and temporal resolution. Faster image acquisition enabled renal CT angiography to become a viable and effective noninvasive alternative in diagnosing renal vascular pathologies. However, with these advances, new challenges in contrast media administration have emerged. Poor synchronization between scanner and contrast media administration have reduced the consistency in image quality with poor spatial and contrast resolution. Comprehensive understanding of contrast media dynamics is essential in the design and implementation of contrast administration and image acquisition protocols. This review includes an overview of the parameters affecting renal artery opacification and current protocol strategies to achieve optimal image quality during renal CT angiography with iodinated contrast media, with current safety issues highlighted.

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein.

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart.