Rationale and objective Osteoporosis, a common non-pathological disease of bones, has been the cause of many disastrous consequences, in terms of physical, psychological, social, and economic loss. Therefore, it is crucial to diagnose it early for timely prevention and treatment of osteoporotic fractures. Dual-Energy X-Ray Absorptiometry (DEXA) is currently routinely used for determining bone mineral density. However, it has its limitations. Nowadays, CT technology has advanced so rapidly that the Hounsfield units (HU) values can be used in opportunistic screening for osteoporosis in patients during routine CT abdomen for other causes. Hence, there would be no need for additional study with DEXA and also reduce radiation exposure. The aim of our research is to determine whether there is a correlation between the bone mineral density and the Tscore measured by DEXA and the HU values measured from the diagnostic CT images of L1-4 vertebrae. Also, to determine reference CT values that would help in screening the patients with osteoporosis. Materials and methods We conducted a retrospective study of 78 female patients who underwent CT lumbar spine, abdomen, and pelvis in our hospital between the years 2016-2020. We collected data of patients who performed DEXA and CT scans within an interval of up to two years. The final collected data was analyzed to find correlation values of HU with age group and with DEXA bone mineral density (BMD) and T-score using Pearson correlation coefficient.

Highlights Test bolus technique increase the diagnostic quality score of the scans performed. Provides better evaluation of the pulmonary arteries and its subsegmental branches. Increase the main pulmonary artery average density, decrease average density of the aorta and pulmonary veins. Increase the confidence and accuracy rate of diagnostic examinations. Volume of IV contrast decreased by 40 % than in bolus tracking.

Background: Congenital pulmonary artery anomalies are variable and need proper diagnosis and treatment. CT angiography with multiplanar reconstruction has the main role in the assessment of these anomalies and this noninvasive method should be the method of choice for preoperative planning and postoperative follow up. The aim of the study is to assess the value of MDCT in the detection of pulmonary arteries anomalies in the pediatric population with complex congenital heart disease in conjunction with echocardiography as an alternative to conventional angiography and to determine the superiority of MDCT in the assessment of other abnormalities such as airway anomalies. Results: In our retrospective study, 52 patients (28 male and 24 females, aged 1 day to 4 years: mean age 2 years) were examined with contrast-enhanced CT. CT examinations were done using a 128-section CT scanner (Siemens Somatom Definition AS) using non-ionic iodinated contrast media. 2D and 3D reconstructions were performed. The correlation was made with echocardiograms. All imaging studies were reviewed. The echo was done to all patients. Surgery and/or catheter angiography performed to all patients, their findings were reviewed and compared to CTA findings. Other abnormalities such as congenital airway anomalies are detected using axial MDCT images and reconstructed imaging techniques. MDCT was accurate in revealing pulmonary artery anomalies. The commonest pulmonary artery anomaly was atresia, stenosis then hypoplasia. These anomalies may be isolated or associated with other congenital heart diseases. In the current study, MDCT could diagnose all cases of pulmonary arterial anomalies with 96% sensitivity, 100% specificity, 98% accuracy, 100% positive, and 94% negative predictive values. CT scans provide accurate information to assess complex spatial relationships of vascular airway compression frequently associated with CHD in the pediatric population. Conclusion: MDCT scanner can be an alternative to diagnostic conventional angiography for the non-invasive assessment of the pulmonary artery. Higher quality multiplanar and 3D reconstruction achieved by the MDCT scanners offer a rapid, reliable and non-invasive technique that can be used for the evaluation and preoperative assessment of thoracic vascular and extra-vascular anatomy in infants and children with suspected congenital heart disease. CT technologies are constantly developing collaboration between radiologists, pediatric cardiologists, and anesthesiologists, which is essential for improving CT performance.

Background: Although gall bladder perforation (GBP) is not common, it is considered a life-threating condition, and the possibility of occurrence in cases of acute cholecystitis must be considered. The aim of this study was to assess the role of multi-slice computed tomography (MSCT) in the assessment of GBP.Results: It is a retrospective study including 19 patients that had GBP out of 147, there were 11 females (57.8%) and 8 males (42.1%), aged 42 to 79 year (mean age 60) presented with acute abdomen or acute cholecystitis. All patients were examined with abdominal ultrasonography and contrast-enhanced abdominal MSCT after written informed consent was obtained from the patients. This study was between January and December 2018. Patients with contraindications to contrast-enhanced computed tomography (CT) (pregnancy, acute kidney failure, or allergy to iodinated contrast agents) who underwent US only were excluded. Patients with other diagnoses, such as acute diverticulitis of the right-sided colon or acute appendicitis, were excluded. The radiological findings were evaluated such as GB distention; stones; wall thickening, enhancement, and defect; pericholecystic free fluid or collection; enhancement of liver parenchyma; and air in the wall or lumen. All CT findings are compared with the surgical results. Our results revealed that the most important and diagnostic MSCT finding in GBP is a mural defect. Nineteen patients were proved surgically to have GBP.Conclusion: GBP is a rare but very serious condition and should be diagnosed and treated as soon as possible to decrease morbidity and mortality. The most accurate diagnostic tool is the CT, MSCT findings most specific and sensitive for the detection of GBP and its complications.

Atlanto-occipital assimilation is one of the most common congenital anomalies observed at the craniocervical junction. It usually is asymptomatic but some have neurological problems such as myelopathy. We report a case of this malformation with unusual neurological symptoms which correlate with radiological findings. The knowledge of this variation may be of importance to orthopedic surgeons, neurosurgeons& radiologists.