Search

Rationale and Objectives: The purpose of this study was to compare tumor volume in a VX2 rabbit model as calculated using semiautomatic tumor segmentation from C-arm cone-beam computed tomography (CBCT) and multidetector computed tomography (MDCT) to the actual tumor volume. Materials and Methods: Twenty VX2 tumors in 20 adult male New Zealand rabbits (one tumor per rabbit) were imaged with CBCT (using an intra-arterial contrast medium injection) and MDCT (using an intravenous contrast injection). All tumor volumes were measured using semiautomatic three-dimensional volumetric segmentation software. The software uses a region-growing method using non-Euclidean radial basis functions. After imaging, the tumors were excised for pathologic volume measurement. The imaging-based tumor volume measurements were compared to the pathologic volumes using linear regression, with Pearson''s test, and correlated using Bland-Altman analysis. Results: Average tumor volumes were 3.5 ± 1.6 cm3 (range, 1.4–7.2 cm3) on pathology, 3.8 ± 1.6 cm3 (range, 1.3–7.3 cm3) on CBCT, and 3.9 ± 1.6 (range, 1.8–7.5 cm3) on MDCT (P < .001). A strong correlation between volumes on pathology and CBCT and also with MDCT was observed (Pearson''s correlation coefficient = 0.993 and 0.996, P < .001, for CBCT and MDCT, respectively). Bland-Altman analysis showed that MDCT tended to overestimate tumor volume, and there was stronger agreement for tumor volume between CBCT and pathology than with MDCT, possibly because of the intra-arterial contrast injection. Conclusions: Tumor volume as measured using semiautomatic tumor segmentation software showed a strong correlation with the “real volume” measured on pathology. The segmentation software on CBCT and MDCT can be a useful tool for volumetric hepatic tumor assessment. [Copyright &y& Elsevier]

Background: No qualitative or quantitative analysis of contrast-enhanced computed tomography (CT) images has been reported for the differentiation between ameloblastomas and central giant cell granulomas (CGCGs)., Aim: To describe differentiating multidetector CT (MDCT) features in CGCGs and ameloblastomas and to compare differences in enhancement of these lesions qualitatively and using histogram analysis., Methods: MDCT of CGCGs and ameloblastomas was retrospectively reviewed to evaluate qualitative imaging descriptors. Histogram analysis was used to compare the extent of enhancement of the soft tissue. Fisher's exact tests and Mann-Whitney U test were used for statistical analysis ( P < 0.05)., Results: Twelve CGCGs and 33 ameloblastomas were reviewed. Ameloblastomas had a predilection for the posterior mandible with none of the CGCGs involving the angle. CGCGs were multilocular (58.3%), with a mixed lytic sclerotic appearance (75%). Soft tissue component was present in 91% of CGCGs, which showed hyperenhancement (compared to surrounding muscles) in 50% of cases, while the remaining showed isoenhancement. Matrix mineralization was present in 83.3% of cases. Ameloblastomas presented as a unilocular (66.7%), lytic (60.6%) masses with solid components present in 81.8% of cases. However, the solid component showed isoenhancement in 63%. No matrix mineralization was present in 69.7% of cases. Quantitatively, the enhancement of soft tissue in CGCG was significantly higher than in ameloblastoma on histogram analysis ( P < 0.05), with a minimum enhancement of > 49.05 HU in the tumour providing 100% sensitivity and 85% specificity in identifying a CGCG., Conclusion: A multilocular, lytic sclerotic lesion with significant hyperenhancement in soft tissue, which spares the angle of the mandible and has matrix mineralization, should indicate prospective diagnosis of CGCG ., Competing Interests: Conflict-of-interest statement: All the authors declare that they have no conflict of interest., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

A 3 month- old boy was admitted with recurrent severe respiratory distress and refractory to therapeutic options. Patient underwent a helical multidetector CT examination. Axial, coronal and three- dimensional imaging, revealed tracheal bronchus, stenosis, diverticulum and bronchiectasis. In this situation, CT scanning, Perfectly 3D imaging is recommend for rule out congenital tracheobronchial tree anomalies. Therefore, with proper evaluation and therapeutic options we can prevent pulmonary complications and infantile mortality.

Purpose: To evaluate the diagnostic value of multidetector computed tomography (MDCT) in radial head or neck fracture, and to evaluate factors that affect MDCI image quality. Materials and Methods: Sixty-six radial fractures in 65 patients, who underwent both radiography and MDCI, were included. Detection of fracture and classification of types were recorded for each modality. Patients were divided into the good (A) and poor (B) image quality groups, and recorded the factors, such as arm positioning, flexion angle, and cancellous bone density. Results: The detection rate of fracture showed no significant difference between the two modalities. However, classification of the fracture type was significantly ac- curate by MDCT (p < 0.0001). Eight cases were only detected on MDCI and three cases were only detected on radiography. Fracture type was discordant in 11 cases. MDCI scanning with raising arm (p < 0.0001), with lesser flexion angle (p = 0.004), and higher cancellous bone density (p = 0.010) showed better image quality. Conclusion: Radiography is a good primary tool for detecting radial head or neck fracture. Hdwever, MDCI can be an additional tool for classifying the fracture type and cases with negative radiographic findings. Arm positioning, flexion angle, and cancellous bone density affect MDCI image quality. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The aim of this study was to assess the rule of the MDCT in the diagnosis of central skull base osteomyelitis complicating otogenic and odontogenic sources as well as assessment of the extensions. Material and methods: This study was conducted on 8 patients. Two patients had skull base osteomyelitis (SBO) complicating malignant otitis externa. Three cases of associated masticator space infection were seen. Two cases with history of oto-mastoiditis and one case of combined oto-mastoiditis and otitis externa were seen. Multi-slice CT machine was used for the assessment of all patients. Results: The involved bony structures showed medullary expansion and sclerosis with cortical discontinuity. Involvement of the foramen ovale, foramen spinosum and pterygo-palatine fossa was noted in 62.5% of cases. Conclusion: The MDCT can precisely detect the source and degree of extension of the fulminate infective process reaching the central skull base. The radiological evaluation of the skull base foramina and pterygo-palatine fossa is critical for the radiologist, which will be the link between different specialties that will deal with such spreading conditions including the oto-rhino-laryngologist, ophthalmogist, dentist, maxillo-facial, head and neck surgeons. [Copyright &y& Elsevier]

Abstract: Background: Despite advent of rapid arterial revascularization as 1st line treatment for acute myocardial infarction (AMI), incomplete restoral of flow at the microvascular level remains a problem and is associated with adverse prognosis, including pathological ventricular remodeling. We aimed to study the association between multidetector row computed tomography (MDCT) perfusion defects and ventricular remodeling post-AMI. Methods: In a prospective study, 20 patients with ST-elevation AMI, treated by primary angioplasty, underwent arterial and late phase MDCT as well as radionuclide scans to study presence, size and severity of myocardial perfusion defects. Contrast echocardiography was performed at baseline and at 4 months follow-up to evaluate changes in myocardial function and remodeling. Results: Early defects (ED), late defects (LD) and late enhancement (LE) were detected in 15, 7 and 16 patients, respectively and radionuclide defects in 15 patients. The ED area (r =0.74), and LD area (r =0.72), and to a lesser extent LE area (r =0.62) correlated moderately well with SPECT summed rest score. By univariate analysis, follow-up end-systolic volume index and ejection fraction were both significantly related to ED and LD size and severity, but not to LE size or severity. By multivariate analysis, end-systolic volume index was best predicted by LD area (p <0.05) and ejection fraction by LD enhancement ratio. Conclusions: LD size and severity on MDCT are most closely associated with pathological ventricular remodeling after AMI and may thus play a role in early identification and treatment of this condition. [Copyright &y& Elsevier]

We present a neonate with a complex congenital cardiopathy and a right-sided diaphragmatic hernia complicated with hepatopulmonary fusion. Radiography, abdominal US and multidetector CT (MDCT) demonstrated right-sided lung hypoplasia and liver herniation. In addition, MDCT angiography showed abnormal pulmonary vascular anatomy. At surgery, a right-sided diaphragmatic hernia with a partially herniated liver and hepatopulmonary fusion was confirmed. There was no aberrant systemic vascular supply towards the lower lobe, as seen in extralobar sequestration. MDCT angiography of the chest and upper abdomen with optimal enhancement and reconstruction of the pulmonary and hepatic vasculature can demonstrate associated anomalies in cases of suspected primary or secondary right lung hypoplasia. [ABSTRACT FROM AUTHOR]

Abdominal ultrasound ( US) is used frequently as a first-line screening tool for abdominal disease. Although computed tomography ( CT) is superior to US in the diagnosis of some abdominal diseases, a major impediment is the requirement of general anesthesia to prevent motion and for safe restraint. With multidetector helical CT, faster examinations allow general anesthesia to be avoided, while producing diagnostic-quality images. Abdominal US and CT were compared for lesion detection in 27 sedated dogs, divided into three even groups based on body weight. Lesions were categorized further as to subjective clinical relevance. In dogs less than 25 kg, there is no significant difference in lesion detection between CT and US. In dogs weighing greater than 25 kg, more lesions were detected with CT than with US ( P = 0.0001), including clinically relevant lesions ( P = 0.0277). From these results, it appears that CT has an advantage in lesion detection in dogs greater than 25 kg, making it a better screening test for abdominal disease in these patients. [ABSTRACT FROM AUTHOR]

Peritoneal carcinomatosis is usually associated with a poor overall survival rate. Recently, introduction of more aggressive surgical treatment and intraperitoneal chemotherapy appears to significantly increase the overall survival rate for these patients. A detailed preoperative assessment of peritoneal carcinomatosis could be very challenging in the field of imaging, but a new aggressive surgical approach requires an accurate preoperative assessment of the disease. Cross-sectional imaging using CT and MRI with diffusion-weighted imaging (DWI) sequences is important for appropriate management of patients with peritoneal carcinomatosis. Appreciation of the spectrum of diagnostic patterns and pitfalls as well as different sites of involvement of peritoneal carcinomatosis using CT and DWI is crucial for appropriate surgical treatment. [ABSTRACT FROM AUTHOR]

Objectives: To assess the role of multidetector computed tomography (MDCT) with multiplanar reconstruction (MPR) and virtual gastroscopy (VG) for detection and differentiation of gastric subepithelial masses (SEMs) by comparison with endoscopic ultrasonography (EUS). Methods: Forty-one patients with a suspected SEM were evaluated using EUS and MDCT. MDCT findings were analyzed based on the consensus of two radiologists who were blinded to the EUS findings. The analysis of the CT features included the location, size, and contours of the tumor, the presence of central dimpling, as well as the growth pattern, enhancement pattern, and enhancement degree. The long diameter (LD) and the short diameter (SD) of each lesion were measured and the LD/SD ratios were calculated. EUS and MDCT results were compared with histopathology for the pathologically proven lesions. For the non-pathologically proven lesions, MDCT results were compared with EUS. Results: Among the 41 patients, 34 SEMs were detected using EUS. For the detection of SEMs with MDCT, a sensitivity of 85.3%, a specificity of 85.7%, a positive predictive value of 96.7%, and a negative predictive value of 54.5% were calculated. The overall accuracy of MDCT for detecting and classifying the SEMs was 85.3 and 78.8%, respectively. Conclusions: MDCT with MPR and VG is a valuable method for the evaluation of SEMs. Specific MDCT criteria for various SEMs may be helpful in making an accurate diagnosis. [ABSTRACT FROM AUTHOR]

Copyright of La Radiologia Medica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We obtained baseline and follow-up bone mineral density (BMD) values of the lumbar spine from sagittal reformations of routine abdominal contrast-enhanced multidetector computed tomography (MDCT) using a reference phantom and assessed their performance in differentiating patients with no, existing, and incidental osteoporotic fractures of the spine. A MDCT-to-QCT (quantitative computed tomography) conversion equation for lumbar BMD measurements was developed by using 15 postmenopausal women (63 ± 12 years), who underwent standard lumbar QCT (L1-L3) and afterward routine abdominal contrast-enhanced MDCT. Sagittal reformations were used for corresponding lumbar BMD measurements. The MDCT-to-QCT conversion equation was applied to baseline and follow-up routine abdominal contrast-enhanced MDCT scans of 149 postmenopausal women (63 ± 10 years). Their vertebral fracture status (no, existing, or incidental osteoporotic fracture) was assessed in the sagittal reformations. A correlation coefficient of r = 0.914 ( p < 0.001) was calculated for the BMD values of MDCT and standard QCT with the conversion equation BMD = 0.695 × BMD − 7.9 mg/mL. Mean follow-up time of the 149 patients was 20 ± 12 months. Fifteen patients (10.1 %) had an existing osteoporotic vertebral fracture at baseline. Incidental osteoporotic vertebral fractures were diagnosed in 13 patients (8.7 %). Patients with existing and incidental fractures showed significantly ( p < 0.05) lower converted BMD values (averaged over L1-L3) than patients without fracture at baseline and at follow-up. In this longitudinal study, BMD values of the lumbar spine derived from sagittal reformations of routine abdominal contrast-enhanced MDCT predicted incidental osteoporotic vertebral fractures. [ABSTRACT FROM AUTHOR]

A 320-row multidetector CT provides the capability for prospective electrocardiogram (ECG)-gated coronary CT angiography (CTA) and tube current modulated cardiac function assessment (CFA). We assessed and compared the effective radiation dose of these two modes. On a prospective basis, we performed ECG-gated cardiac CT on 119 patients (87 were males). For heart rates (HRs) ≦65 beats/min (bpm), we used one-heartbeat acquisition and half-scan reconstruction. HRs from 66 to 79 bpm and ≧80 bpm were scanned with either two or three heartbeats acquisitions, respectively. We used two types of scans. One type was based on a prospective ECG-gated CTA mode and the other using a tube current modulated CFA mode covering an entire R-R interval. The mean BMI of patients was 25.4 (range 18.8-49.3). Fifty-one patients (42.9 %) underwent CFA scanning, while the remaining 68 (57.1 %) had CTA. The majority of patients completed the scan in a single heartbeat (59.7 %). The mean dose of CTA mode at 65-85 % phase window for one and two heartbeats was 3.68 mSv (2.40-7.23) and 8.61 mSv (6.76-10.60), respectively. The mean dose of CFA mode for a single heartbeat measurement with dose modulation (25 % dose for CFA, and 100 % dose during 65-85 % phase window for CTA) was 6.32 mSv (4.69-8.89). CTA with prospective ECG-gating allows for acceptable image quality and radiation dose. HR reduction is mandatory to minimize radiation exposure. Global left ventricle function can be assessed with a single heartbeat within an acceptable radiation dose. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to evaluate the normal anatomy and variations of testicular veins by multidetector CT (MDCT). Materials and methods: This prospective study included 101 male patients who underwent abdominal CT for various clinical indications. Mean age of patients was 53 years. Images were obtained by dual source 64-slice MDCT ( n = 61) and 64-MDCT ( n = 41). Images were analyzed using 1 mm thick slices on a dedicated workstation. The number of testicular veins, drainage site and diameter of proximal, mid and distal testicular veins were recorded. Results: Testicular veins were visualized in all patients. There were single right testicular vein in 99 (98%) patients and 2 (2%) patients had duplicated right testicular veins (total 103 veins). Right testicular vein drained into inferior vena cava in 88 (87.1%) patients and right renal vein in 13 (12.9%) patients. One of duplicated right testicular veins drained into inferior vena cava and other paired drained into right renal vein and inferior vena cava separately. There were single left testicular vein in 88 (87.1%) patients and 13 (12.9%) patients had duplicated veins (total 14 veins). All left testicular veins drained into left renal vein. Conclusion: 64-MDCT enables evaluation of testicular veins in all patients. Right and left testicular veins are usually single, but can be duplicated more commonly. [ABSTRACT FROM AUTHOR]

Abstract: Portal biliopathy refers to biliary abnormalities secondary to extrahepatic portal vein obstruction and cavernous transformation and is caused by vascular compression from peribiliary collateral vessels, producing segmental stenoses of the common bile duct and abnormal liver function test (LFT) results. A review of imaging studies yielded 18 patients with abnormal LFT results, biliary tract dilatation, and extrahepatic portal vein obstruction with cavernous transformation. Multidetector computed tomography and magnetic resonance imaging showed biliary stenotic segments in 11 patients secondary to extrinsic compression from enlarged peribiliary collaterals. Clinical and imaging follow-up demonstrated improvement in LFT results with minimal decrease in bile duct dilatation, eliminating percutaneous or endoscopic biliary intervention. [Copyright &y& Elsevier]

Objective: To evaluate the patterns of pulmonary venous drainage into the left atrium and to determine the frequency of each variant of pulmonary venous anatomy. Materials and methods: After institutional review board approval (No. 09JUL011148), 300 studies of thoracic multidetector computed tomography were retrospectively reviewed for the anatomical features of the pulmonary vein and its drainage pattern into the left atrium. The percentage of each pattern was calculated. Results: The anatomy of pulmonary venous drainage in 300 patients (150 male and 150 female, mean age 60.16 years) showed some variation. In the right pulmonary vein, the most common drainage pattern was two ostia (90.33%), followed by three to five ostia (6.33%) and a single ostium (3.33%). There were one or two separate middle lobe vein ostia in groups of more than two openings. On the left side, there were two patterns; a single venous ostium (59%) was much more common than two ostia (41%). In both right and left pulmonary veins, there were five cases (2 male, 3 female) that had a single pulmonary venous ostium, bilaterally. However, there were only 17 cases (5.67%), out of 300 enrolled in this study, that had bilateral pulmonary venous ostial variations. Conclusion: A classification system to succinctly describe pulmonary venous drainage patterns was developed. In left-sided drainage, a single left pulmonary ostium was the most common variation. The right-sided venous drainage varied more in both number and pattern than those of the left side; nevertheless, bilateral pulmonary venous ostial variation was not frequently found. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: The purpose of this study is to evaluate the ability of multidetector CT (MDCT) in predicting resectability of pancreatic tumors. Patients and methods: Thirty-nine patients were included in this study, there were 29 males and 10 females, and their age range was 44–73years with a mean age of 58.3years. All the patients were subjected to contrast enhanced biphasic examinations on 64-slice CT machine. Results: Twenty-one patients (53.8%) were considered inoperable with unresected tumor, the remaining 18 patients (46.2%) were considered suitable for tumor resection according to MDCT criteria. 15 out of the 18 patients (83.3) had a successful tumor resection while the remaining 3 (16.7%) showed unresectable tumor during operation. On the basis of pathology results 12 patients out of the 18 (66.7%) had successful surgery with negative tumor margin, and a positive predictive value of 66.7% and accuracy of 66.7%. Conclusions: There is better prediction of resectability of pancreatic tumors with the development of MDCT technology. As compared to Helical computed tomography (HCT) studies, there is a rise in the rate of successful surgical resection. The positive predictive value of multidetector computed tomography for resectable pancreatic tumors is decreased when pathologic results are used as a reference standard. [Copyright &y& Elsevier]

Objectives: To evaluate the impact of Adaptive Iterative Dose Reduction (AIDR) on image quality and radiation dose in phantom and patient studies. Methods: A phantom was examined in volumetric mode on a 320-detector CT at different tube currents from 25 to 550 mAs. CT images were reconstructed with AIDR and with Filtered Back Projection (FBP) reconstruction algorithm. Image noise, Contrast-to-Noise Ratio (CNR), Signal-to-Noise Ratio (SNR) and spatial resolution were compared between FBP and AIDR images. AIDR was then tested on 15 CT examinations of the lumbar spine in a prospective study. Again, FBP and AIDR images were compared. Image noise and SNR were analysed using a Wilcoxon signed-rank test. Results: In the phantom, spatial resolution assessment showed no significant difference between FBP and AIDR reconstructions. Image noise was lower with AIDR than with FBP images with a mean reduction of 40%. CNR and SNR were also improved with AIDR. In patients, quantitative and subjective evaluation showed that image noise was significantly lower with AIDR than with FBP. SNR was also greater with AIDR than with FBP. Conclusion: Compared to traditional FBP reconstruction techniques, AIDR significantly improves image quality and has the potential to decrease radiation dose. Key Points: [ABSTRACT FROM AUTHOR]

Abstract: Objective: Assess the multidetector computed tomography (MDCT) in the anatomic appearance of the diaphragm, its variants and defects. Materials and methods: Retrospective study of 142 scans of patients in their 20s–80s using 64 rows MDCT from January 2010 to March 2011. According to Gale (1986), anterior diaphragm appearance on axial image is classified into type 1: continuous, type 2: discontinuous, and type 3: broad. Sagittal reformatted image is classified into type A: downward slope, type B: upward slope, and type C: flat. According to Caskey et al. (1989), posterior diaphragm defects are classified into type 1: localized defect with maintenance of its continuity, type 2: defect in parallel layers with maintenance of its continuity and type 3: loss of diaphragmatic continuity. Results: Anterior diaphragm was assessed in 141 cases. On axial images, types 1, 2, and 3 were found in 36.9%, 41.1%, and 22.0% respectively. On sagittal reformatted images, types A, B, and C were found in 32.6%, 41.1%, and 26.2% respectively. One case had Morgagni hernia. Significant relationship between the types at the axial and sagittal images was found (r =0.205, P <0.05). 2.8% Posterior diaphragmatic defects. High significant relationship between the age and diameter of oesphageal hiatus was found (P <0.05). Conclusion: The multiplanar capability of MDCT is adding a new scope of assessment of diaphragm and its variants. [Copyright &y& Elsevier]

Abstract: Purpose: To demonstrate the superior role of multidetector computed tomography (MDCT) in delineation of the extracardiac vascular abnormalities including the pulmonary arterial tree, major aortopulmonary collateral arteries (MAPCAs), patent ductus arteriosus (PDA), and also the detection of the common and uncommon findings in Fallot Tetralogy cases for proper pre-surgical evaluation. Material and methods: A retrospective study of all multidetector CT images acquired to evaluate suspected cases of Tetralogy of Fallot sent by their respective referring physicians between April 2009 and August 2010. A total of 23 cases were included in this study. MDCT protocol, image analysis and calculations used in the diagnosis are explained in detail. Results: Detailed explanation of the MDCT imaging findings in the 23 cases with Tetralogy of Fallot, as well as the common and uncommon associations of the disease, namely pulmonary atresia, MAPCAs, PDAs, atrial septal defects (ASDs), right sided aortic arch, and a few less common associations. Conclusion: A customized approach to MDCT imaging improves the diagnostic accuracy and reduces unneeded prolongation of the study and sedation times. A careful preoperative perceptive of the complex cardiovascular anatomy in patients with Tetralogy of Fallot aids in exposing the patient to a directed and prepared surgical approach. [Copyright &y& Elsevier]

Abstract: Introduction: Living donor liver transplantation is increasingly being used to help compensate for the increasing shortage of cadaveric liver grafts. However, the extreme variability of the hepatic vascular systems can impede this surgical procedure. Aim of the work: The aim of the study was to demonstrate the role of multidetector CT (MDCT) in evaluation of potential right lobe living donors for liver transplantation. Methods: The study included twenty-five liver donors in pre-operative assessment before liver transplantation. Triphasic abdominal MDCT. Post-processing techniques including multiplanner reformation (MPR), maximum intensity projection (MIP) and volume rendering (VR). Results: Twenty donors had Michels type I variant, one donor with type Michels type II, while the remaining four had Michels type III. Sixteen donors had dominant right hepatic vein, five had late confluence of the middle hepatic vein; while remaining four donors had dominant middle hepatic vein. Twenty donors had type A portal vein branching, while the remaining five had type B portal vein branching. The percentage of right hepatic lobe for the whole liver volume ranging from 40% to 55%. Conclusion: Multidetector CT provides important information in evaluation of potential living donors for liver transplantation. [Copyright &y& Elsevier]

The purpose of the study was to determine the performance of a 64-row multidetector computed tomography (MDCT) in identifying peritoneal metastases in ovarian cancer patients undergoing surgical staging or cytoreduction.This retrospective study included 76 patients who underwent surgical staging (n = 11) or cytoreduction (n = 65). Patients had MDCT before surgery (mean, 24 [SD, 16.9] days) as well as correlative surgicopathologic data. For the imaging analysis, the peritoneal cavity was divided to 28 segments, which were assessed for absence or presence of disease. Rate of optimal cytoreduction at the time of surgery was recorded. The standard of reference for this study was surgery, unless there was proof of metastasis as assessed by follow-up imaging. Sensitivity and predictive accuracy of CT and surgery compared with the standard of reference were calculated.The overall sensitivity and accuracy were 81.2% and 94.3% for MDCT and 87.4% and 97.2% for surgery (P = 0.14, P = 0.007), respectively. There was no difference in the detection of lesions 1 cm or greater between MDCT and surgery (89.3% and 84.9%, respectively; P = 0.31); however, MDCT was less sensitive than surgery in detecting disease sites of less than 1 cm (65.5% and 92.3%, respectively; P = 0.001). For the subgroup of patients undergoing cytoreduction after neoadjuvant chemotherapy (NAC) (n = 30), sensitivities for MDCT and surgery were similar (80% and 76.9%, respectively [P = 0.71]). Although sensitivity of CT was not altered by NAC (P = 0.92), there was a significant decrease in sensitivity of surgical assessment after NAC (94% vs 76.9%; P = 0.003).Multidetector computed tomography (MDCT) has similar sensitivity as surgery for peritoneal metastases of 1 cm or greater. The maintained sensitivity of MDCT in detecting peritoneal disease after NAC, which is underestimated at surgery, may help surgical planning and may improve optimal cytoreduction rate in this group of patients. [ABSTRACT FROM AUTHOR]

Abstract: Background: The aim of this study was to evaluate the peritoneal computed tomography (CT) attenuation values and relate them to the severity of peritonitis in patients with gastrointestinal tract (GI) perforations. Methods: A total of 56 consecutive patients with GI perforations who underwent CT scan and emergency laparotomy in our hospital were enrolled in this study. The CT attenuation values of the peritoneum were measured on a workstation by 2 independent investigators, and were investigated in relation to the severity of illness and hospital mortality. Results: Peritoneal CT attenuation values in hospital nonsurvivors were significantly lower than those in survivors. There was significant negative correlation between peritoneal CT attenuation values and sequential organ failure assessment score, acute physiology and chronic health evaluation II score, and the Mannheim peritonitis index. Conclusions: The evaluation of peritoneal CT attenuation values in patients with peritonitis is simple and can be used for objective assessment of the severity of peritonitis. [Copyright &y& Elsevier]

Abstract: Introduction: Pulmonary involvement is a common finding in adults with systemic lupus erythematosus (SLE) also it is one of the most important systems that can be affected in Juvenile onset SLE (JOSLE). Early detection and evaluation of the extent and severity of pulmonary involvement are quite critical for disease prognosis and patients management. Aim of the work: To determine the frequency and type of pleuropulmonary involvement in JOSLE using pulmonary function tests (PFTs) and multidetector CT (MDCT). Patients and methods: Twenty five patients with JOSLE were evaluated for the detection of pleuropulmonary affection in them. The evaluation included clinical, functional & radiological examination using MDCT as a recent & accurate modality for chest imaging. Based on clinical evaluation, patients were divided into two groups; group A (No=16) and group B (No=9), consisting of those asymptomatic and symptomatic as regard pleuropulmonary symptoms, respectively. Results: This study revealed that PFT abnormalities were detected in 60% of all studied JOSLE patients while MDCT abnormalities were detected in 52% of them. 37.5% of the asymptomatic patients had abnormal PFTs & 31.25% of them had abnormal findings on MDCT. There was statistically significant difference between patients groups regarding SLEDAI, percentages of abnormal PFTs, abnormalities in plain X-ray and MDCT. With the exception of forced expiratory flow at 25–75% of forced vital capacity (FEF25–75%), the study revealed statistically significant lower values of mean±SD of all measured PFTs in group B compared to group A. The most frequent MDCT findings in all studied patients were pleural effusion and pleural thickening in 16% of all findings, also ground glass opacities found in 16% of all abnormalities suggesting early interstitial lung disease. Conclusion: Clinical assessment and PFTs revealed a significant percentage of pleuropulmonary involvement in JOSLE patients. MDCT can be helpful in diagnosing the pulmonary involvement in asymptomatic JOSLE patients with normal chest X-ray and uncertain PFT. [Copyright &y& Elsevier]

Methods for non-invasive, cardiac risk assessment have historically relied on exercise stress testing with or without echocardiography or radionuclide imaging and pharmacological stress testing when appropriate. More recently, CT-based modalities like CT angiography (CTA) have been shown to reliably differentiate low from high-risk coronary disease. The advent of newer CT technology now allows for CT-based myocardial perfusion imaging (CTP) that provides functional information, that when analyzed with anatomic data from CTA, can provide a comprehensive risk assessment strategy. In this review, we discuss the research and implementation; as well as the quantitative, semiquantitative, and qualitative methods of image analysis of CT-based perfusion. We also discuss the present state of technology and challenges associated with the methodology. In each section, when appropriate, we provide some information regarding the translation of these methods being utilized in the international, multicenter CORE320 study that is evaluating the combined CT-based imaging (CTA and CTP) strategy of risk assessment in comparison to the combined reference standard of radionuclide myocardial perfusion imaging and invasive angiography. [ABSTRACT FROM AUTHOR]

Background: The ability of multidetector computed tomography (MDCT) to detect stress-induced myocardial perfusion abnormalities is of great clinical interest as a potential tool for the combined evaluation of coronary stenosis and its significance. However, stress testing requires repeated scanning that is associated with additional radiation exposure and iodine contrast. Objective: Our goal was to determine the effects of reduced tube voltage and contrast dose on the ability to detect perfusion abnormalities. Methods: We studied 40 patients referred for coronary CT angiography (CTA) who agreed to undergo additional imaging after administration of an A2A-agonist (regadenoson 0.4 mg). Images were acquired at rest and during hyperemia with prospective gating with 120 kV tube voltage with 80–90 mL of contrast in 20 patients (group 1) and 100 kV with 55–70 mL of contrast in the remaining 20 patients (group 2). Custom 3D analysis software was used to define 3D myocardial segments and measure x-ray attenuation in each segment. In each group of patients, myocardial attenuation was averaged for segments supplied by coronary arteries with stenosis causing >50% luminal narrowing on coronary CTA and separately for segments supplied by arteries without significant stenosis. Results: Coronary CTA detected stenosis >50% in 23 of 120 coronary arteries in 16 of 40 patients. In all patients combined, myocardial attenuation increased from 86 ± 9 at rest to 110 ± 17 HU with stress, reflecting an increase in tissue blood flow, despite the decrease in left ventricular cavity attenuation (347 ± 72 to 281 ± 55 HU), reflecting an increase in cardiac output. Importantly, in both groups, myocardial attenuation was equally reduced in segments supplied by diseased arteries (group 1: 119 ± 19 vs 103 ± 14 HU, P < 0.05; group 2: 108 ± 20 vs 97 ± 16 HU, P < 0.05), despite the 74% reduction in radiation (from 7.4 ± 2.8 to 1.9 ± 0.45 mSv) and the 28% reduction in contrast dose (from 84 ± 7 to 60 ±7 mL) (both P < 0.05). Conclusions: Regadenoson stress MDCT imaging can detect hypoperfused myocardium even when imaging settings are optimized to provide a significant reduction in radiation and contrast doses. [Copyright &y& Elsevier]

We report a case of syphilitic aortitis complicated by multiple aortic aneurysms in a 50-year-old man with elevated rapid plasma reagin titer of 1:128 and positive Treponema pallidum particle agglutination test. 256-slice MDCT depicted two saccular aneurysms in the descending thoracic aorta with a markedly thick mural thrombus causing the trachea and esophagus to shift to the right. Thickening of the aortic wall was also noted. Stenting of the proximal descending thoracic aortic aneurysm and aorto-right common carotid artery bypass were performed. Operative findings revealed thickening of the descending thoracic aortic wall with a coarse luminal surface. [ABSTRACT FROM AUTHOR]

The purpose of this article is to provide a current review of multidetector CT (MDCT) and MRI findings and imaging protocols for the cardiovascular diseases that can precipitate systemic embolism. These conditions include intracardiac thrombus or tumors, paradoxical embolism through right-to-left shunts, and diseases of the thoracic aorta. MDCT and MRI may be helpful for detection of these conditions. Familiarity with the pathogenesis and CT and MRI appearance of these conditions is important as their detection may have a major impact on patient management. [ABSTRACT FROM AUTHOR]

Copyright of La Radiologia Medica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Venous leak evaluation remains a challenge in many ED patients. Adequate anatomical evaluation may help with optimizing therapeutic strategies. Propose a new classification of venous leakage using multidetector computed tomography (MDCT) cavernography, after contrast media intracavernous injection (ICI), under pharmacological stimulation. Thirty-eight patients gave informed consent for the study: 34 complained of ED, unsatisfied with treatment and suspected to have cavernovenous leak; four having morphological anomalies and needing surgery. Patient's clinical history, including age, vascular risk factors, penile nitric oxide release test, Doppler ultrasound and previous treatments were evaluated. MDCT consisted in: 1-ICI of 1 mL of vasoactive medications containing papaverine, chlorydrate (20 mg), urapidil chlorydrate (2.75 mg) and alprostadil (10 mcg); 2-ICI of 20-60 cc of diluted contrast media (1/3) using 20 cc of Ioprimide (300 mg/mL); 3-Spiral MDCT acquisition and three-dimensional volume rendering. Erection degree was assessed using the erection hardness score (EHS); venous drainage was analyzed and deep, superficial veins (SVs), and caverno-spongious communications identified. MDCT findings were compared with clinical data. The deep dorsal vein (DDV) was opacified in 58% of patients and the SV in 50%. Cavernospongious communications were visible in 18.4%. Sixteen percent presented no visible drainage. A new classification of venous drainage anomalies is proposed: A-No visible drainage (N = 8); B-DDV and preprostatic plexus opacification (N = 11); C-Exclusive SV opacification (N = 10); D-Opacification of both SV and DDV (N = 9). All patients (with one exception) in group A quoted 4 at the EHS vs. none in the others groups ( P < 0.0001, exact Fisher test). One patient in group A needed venous drainage due to prolonged erection. MDCT after ICI contrast media was able to differentiate between various venous pathways in men with venous origin ED, leading to a new anatomical classification. Absence of leakage was associated with normal erection under pharmacological stimulation. [ABSTRACT FROM AUTHOR]

In transpedicular surgical operations, the pedicle should be safely penetrated. In this study, we hypothesize that morpho-densitometric data describing the physical status of the pedicle isthmus in osteoporotic versus control postmenopausal women may be generated using high-resolution three-dimensional images obtained from routine abdominal multidetector computed tomography (MDCT) scans. Thus, 32 osteoporotic and 38 postmenopausal control women had a routine abdominal scan using a 16-row CT scanner. Images of the pedicle isthmus of the L2-L4 vertebrae were generated at the plane that was vertical to the pedicle axis. Several indices were calculated based on the measurements of outer and inner dimension of the pedicle isthmus, pedicle isthmus area, and pedicle isthmus endosteal area. The mean Hounsfield unit number within the isthmus endosteal area (HU(IEA)) and the trabecular portion of the vertebral body (HU(VERT)) were measured. All subjects had a dual X-ray absorptiometry scan (DXA) in the lumbar spine. Most of the indices calculated showed statistically significant differences between osteoporotic and control women. HU(IEA) was significantly correlated to T-score (r = 0.580, P < 0.0001). HU(IEA) showed the best discriminatory ability between the two groups (area under ROC curve, 0.840). Routine abdominal MDCT can be used to assess the morpho-densitometric characteristics of the lumbar pedicle isthmus and differentiate osteoporotic from control postmenopausal women. [ABSTRACT FROM AUTHOR]

Copyright of La Radiologia Medica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Purpose: To propose a strategy for early diagnosis and management of intrahepatic vascular shunts (IHVSs). Patients and Methods: We systematically screened 3143 patients liable to develop IHVSs. Diagnosed patients were comprehensively evaluated using color Doppler and multiphasic CT. Our management strategy based on imaging and clinical findings and categorized patients into three groups with different lines of management and we assessed the degree of shunt occlusion and clinical outcome. Results: IHVSs were diagnosed in 134 patients. Two types of shunts were identified; arteriovenous (72%) and venovenous (28%). Small simple shunts (32%) showed no morphological or hemodynamic changes. Small complex shunts (57%) showed mild alterations in Doppler spectra. Large and aneurismal shunts (11%) showed increased diameters and flow velocities of the shunt vessels with alteration of flow pattern. By CT the vessels opacified during the early arterial phases in arteriovenous, and during the portovenous phase in venovenous shunts. During management, group I included 42%; 38% were conservatively managed and 4% underwent TIPS. Group II included 57% who underwent successful embolization in 50%, and <80% reduction in 7% of patients who underwent surgery. Direct surgery was selected for 1% of patients. Conclusion: Using color Doppler ultrasonography complemented by multiphasic CT allowed early diagnosis and evaluation of IHVSs and selection of the suitable treatment. Our management strategy allowed practical therapeutic implications and yielded good results. [Copyright &y& Elsevier]

Abstract: Coronary artery calcium (CAC) scanning is an important tool for risk stratification in intermediate-risk, asymptomatic subjects without previous coronary disease. However, the clinical benefit of improved risk prediction needs to be balanced against the risk of the use of ionizing radiation. Although there is increasing emphasis on the need to obtain CAC scans at low-radiation exposure to the patient, very few practical documents exist to aid laboratories and health care professionals on how to obtain such low-radiation scans. The Tomographic Imaging Council of the Society for Atherosclerosis Imaging and Prevention, in collaboration with the Prevention Council and the Society of Cardiovascular Computed Tomography, created a task force and writing group to generate a practical document to address parameters that can be influenced by careful attention to image acquisition. Patient selection for CAC scanning should be based on national guidelines. It is recommended that laboratories performing CAC examinations monitor radiation exposure (dose-length-product [DLP]) and effective radiation dose (E) in all patients. DLP should be <200 mGy × cm; E should average 1.0–1.5 mSv and should be <3.0 mSv. On most scanner platforms, CAC imaging should be performed in an axial mode with prospective electrocardiographic triggering, using tube voltage of 120 kVp. Tube current should be carefully selected on the basis of patient size, potentially using chest lateral width measured on the topogram. Scan length should be limited for the coverage of the heart only. When patients and imaging parameters are selected appropriately, CAC scanning can be performed with low levels of radiation exposure. [Copyright &y& Elsevier]

Abstract: Objective: To analyse the spectrum of Takayasu''s arteritis (TA) on multidetector CT angiography (MDCTA). Materials and methods: A retrospective analysis of the MDCTA findings was performed on 15 patients clinically diagnosed as Takayasu''s arteritis. The spectrum and incidence of imaging findings on CTA were compared to studies in literature on catheter angiography in Takayasu''s arteritis. Laboratory parameters were available in nine patients. The disease was considered active if erythrocyte sedimentation rate (ESR) levels were elevated and ‘C’ reactive protein (CRP) was positive. An attempt was made to correlate disease activity with the imaging findings. Results: Ascending aorta, arch of aorta and descending thoracic aorta were involved in 14 out of 15 (93%) patients. The wall thickness varied between 1 and 10mm with maximal involvement in arch and descending thoracic aorta. Major neck vessels were involved in 11 (73%) patients with most pronounced changes seen in the brachiocephalic trunk, left common carotid artery (CCA) and left subclavian artery (SCA). Abdominal aorta and its branches were involved in all the 11 (100%) patients in whom abdominal CTA was performed. Celiac axis and SMA were involved in 10 (91%) and seven (64%) patients, respectively while renal artery stenosis was present in five (45%) patients. In six patients, ESR was elevated and CRP was positive indicating active disease. All patients in whom the laboratory parameters were available showed mural thickening in the aorta and at least one of the neck vessels except for one patient with inactive disease who had aortic mural thickening only. Conclusion: MDCTA provides information about both the vessel wall and lumen in patients with Takayasu''s disease. [Copyright &y& Elsevier]

Abstract: Solid-pseudopapillary neoplasms of the pancreas are uncommon and usually occur in young women. They are generally large, encapsulated masses with mixture of solid, cystic, and hemorrhagic components. Some cases have atypical features; for example, they can form a small predominantly solid mass and produce dilatation of the main pancreatic duct. In this article we discuss and illustrate the spectrum of the appearances of this distinctive neoplasm on multidetector CT. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To investigate the volume-doubling time (VDT) of histologically proved pulmonary nodules showing ground glass opacity (GGO) at multidetector CT (MDCT) using computer-aided three-dimensional volumetry. Materials and Methods: We retrospectively evaluated 47 GGO nodules (mixed n = 28, pure n = 19) that had been examined by thin-section helical CT more than once. They were histologically confirmed as atypical adenomatous hyperplasia (AAH, n = 13), bronchioloalveolar carcinoma (BAC, n = 22), and adenocarcinoma (AC, n = 12). Using computer-aided three-dimensional volumetry software, two radiologists independently performed volumetry of GGO nodules and calculated the VDT using data acquired from the initial and final CT study. We compared VDT among the three pathologies and also compared the VDT of mixed and pure GGO nodules. Results: The mean VDT of all GGO nodules was 486.4 ± 368.6 days (range 89.0–1583.0 days). The mean VDT for AAH, BAC, and AC was 859.2 ± 428.9, 421.2 ± 228.4, and 202.1 ± 84.3 days, respectively; there were statistically significant differences for all comparative combinations of AAH, BAC, and AC (Steel-Dwass test, P < .01). The mean VDT for pure and mixed GGO nodules was 628.5 ± 404.2 and 276.9 ± 155.9 days, respectively; it was significantly shorter for mixed than pure GGO nodules (Mann-Whitney U-test, P < .01). Conclusion: The evaluation of VDT using computer-aided volumetry may be helpful in assessing the histological entities of GGO nodules. [ABSTRACT FROM AUTHOR]

We present a 10-month-old boy with cyanosis. This is a rare case of pulmonary atresia, ventricular septal defect (VSD), major aorto-pulmonary collateral arteries (MAPCAs) to the right lung with absent native right pulmonary artery (RPA) in association with anomalous left pulmonary artery (LPA) from the ascending aorta (AAo). Echocardiography was unable to identify all of the cardiovascular abnormalities. Multidetector CT demonstrated all of these abnormalities and is the investigation of choice instead of cardiac catheterization. [ABSTRACT FROM AUTHOR]

Introduction. Renal cell carcinoma (RCC) often invades the renal vein and may extend into the inferior vena cava or right atrium [1]. The purpose of this study was to evaluate the diagnostic capabilities of magnetic resonance imaging (MRI) and computed tomography (CT) in patients with venous invasion RCC and correlated the results with histopathological and intraoperative findings. Materials and Methods. 28 patients were diagnosed with RCC with venous tumor thrombus in the period from January 2009 to December 2009. Before their operation, four patients had contrast enhanced CT, three patients had contrast enhanced MRI and 21 patients were assessed for suspected venous extension of RCC with both methods. Images obtained by both techniques were assessed for the presence of tumour thrombus, its level (including any extension into the contralateral renal vein or hepatic veins), vessel wall adherence or invasion, and local tumour staging (lymph node metastases, capsular penetration, contiguous organ involvement). All images were analyzed by experienced radiologists. One pathologist reported all pathology specimens and the superior extent of tumor thrombus were confirmed by the surgeon at each operation. CT and MRI results were compared with surgical and pathological findings. Results. 17 patients (60.7%) had RCC on the right side and 11patients (39.3%) on the left side. According to Novick classification, clinical and histopathological findings, 15 patients (53.5%) are in group A tumor thrombus, seven patients (25%) group B, four patients (14.2%) group C and two patients (7.1%) group D. CT accurately diagnosed the upper extent of the tumour thrombus in 23 cases (92%). MRI accurately predicted the upper extent of the thrombus in all cases. Seven patients had metastatic involvement of regional lymph nodes. Pulmonary metastases were seen in three cases. Conclusions. CT and MRI are common imaging methods in diagnosing the superior extent of tumor thrombus in renal cell carcinoma. With the development of Multidetector CT, its accuracy in defining tumor thrombus in RCC is comparable to MRI. [ABSTRACT FROM AUTHOR]

We aimed to assess intra- and inter-observer reproducibility in evaluating volume and characteristics of non-calcified coronary plaques (NCPs) using a 256-slice multi-detector computed tomography (MDCT) angiography and dedicated automated plaque analysis software in asymptomatic individuals. Forty-two NCPs from 39 patients with a vessel diameter >2 mm were evaluated using a 256-slice MDCT with dedicated automated plaque analysis software. Two independent observers analyzed the characteristics of NCPs, including plaque volume ( vol), mean CT number of the NCPs in Hounsfield units (HU), and remodeling index (RI). One of the observers repeated the evaluation of all datasets after an interval of at least 4 weeks. Bland-Altman analysis and concordance correlation coefficients (CCCs) were used to determine intra- and inter-observer variability. For vol measurements, the 95% limits of agreement were −21.6 and 13.2 mm, and −24.6 and 20.3 mm for intra- and inter-observer variability, respectively. For HU measurements, the 95% limits of agreement were −22.2 and 20.8 HU, and −21.1 and 21.0 HU for intra- and inter-observer variability, respectively. For RI measurements, the 95% limits of agreement were −0.38 and 0.39, and −0.51 and 0.36 for intra- and inter-observer variability, respectively. The CCCs was very high for all measurements, ranging from 0.90 to 0.98. Using 256-slice MDCT with dedicated automated plaque analysis software, intra- and inter-observer reproducibility were excellent in evaluating the volume and characteristics of NCP in asymptomatic individuals. [ABSTRACT FROM AUTHOR]

The recent technical development of multidetector CT (MDCT) has contributed to a substantial increase in its diagnostic applications and accuracy in children. A major drawback of MDCT is the use of ionising radiation with the risk of inducing secondary cancer. Therefore, justification and optimisation of paediatric MDCT is of great importance in order to minimise these risks (“as low as reasonably achievable” principle). This review will focus on all technical and non-technical aspects relevant for paediatric MDCT optimisation and includes guidelines for radiation dose level-based CT protocols. [ABSTRACT FROM AUTHOR]

Purpose: The aims of this study were to collect data relating to radiation dose delivered by multidetector CT scanning at 10 hospitals and private practices in Queensland, Australia, and to test methods for dose optimization training, including audit feedback and didactic, face-to-face, small-group teaching of optimization techniques. Methods: Ten hospital-based public and private sector radiology practices, with one CT scanner per site, volunteered for the project. Data were collected for a variety of common adult and pediatric CT scanning protocols, including tube current–time product, pitch, collimation, tube voltage, the use of dose modulation, and scan length. A one-day feedback and optimization training workshop was conducted for participating practices and was attended by the radiologist and medical imaging technologist responsible for the project at each site. Data were deidentified for the workshop presentation. During the feedback workshop, a detailed analysis and discussion of factors contributing to dose for higher dosing practices for each protocol occurred. The postoptimization training data collection phase allowed changes to median and spread of doses to be measured. Results: During the baseline survey period, data for 1,208 scans were collected, and data from 1,153 scans were collected for the postoptimization dose survey for the 4 adult protocols (noncontrast brain CT, CT pulmonary angiography , CT lumbar spine, and CT urography). A mean decrease in effective dose was achieved with all scan protocols. Average reductions of 46% for brain CT, 28% for CT pulmonary angiography, 29% for CT lumbar spine, and 24% CT urography were calculated. It proved impossible to collect valid pediatric data from most sites, because of the small numbers of children presenting for multidetector CT, and phantom data were acquired during the preoptimization and postoptimization phase. Substantial phantom dose reductions were demonstrated at all sites. Conclusion: Audit feedback and small-group teaching about optimization enabled clinically meaningful dose reduction for a variety of common adult scans. However, access to medical radiation physicists, assistance with time-consuming data collection, and technical support from a medical imaging technologist were costly and critical to the success of the program. [Copyright &y& Elsevier]

Atherosclerotic renal artery stenosis (ARAS) is increasingly identified in patients with end-stage renal disease. Renal function in ARAS patients deteriorates more frequently than in nonatherosclerotic renal artery stenosis (RAS). This study was designed to test the hypothesis that atherosclerosis modifies the relationship between single-kidney hemodynamics and function and the severity of stenosis. The degree of unilateral RAS in domestic pigs (4 normal, 26 RAS, and 22 ARAS) was correlated with renal function and hemodynamics evaluated by 64-slice multidetector computerized tomography before and after endothelium-dependent challenge with ACh. The degree of stenosis and increase in mean arterial pressure were similar in RAS and ARAS. Stenotic single-kidney volume, blood flow, glomerular filtration rate, and cortical perfusion were lower than normal in both RAS and ARAS, but only in RAS correlated inversely with increasing degree of stenosis (r = 0.62, r = -0.49, r = -0.51, and r = -0.46, respectively, P < 0.05 for all). Basal tubular fluid concentration capacity and stenotic cortical perfusion response to ACh were both blunted only in ARAS. This study shows that atherosclerosis modulates the impact of a stenosis in the renal artery on stenotic kidney hemodynamics, function, and tubular dynamics. These observations underscore the direct intra-renal effect of atherogenic factors on the kidneys. [ABSTRACT FROM AUTHOR]

Background: Scanning with 64-slice multidetector row CT (MDCT) is usually faster than blood flow in peripheral arteries of the lower extremities, and the distal arteries of lower extremities are difficult to visualize, particularly in elderly patients. Thus, the optimal table speed for CT angiography (CTA) studies should be adjusted for appropriate patient age groups. Objective: We evaluated the relative efficacy of different table speeds in several age groups of patients with suspected peripheral arterial occlusive disease (PAOD) undergoing CTA of lower extremity arteries, as a guideline for routine use. Methods: This retrospective study reviewed routine CTA of the lower extremity arteries of 107 patients with suspected PAOD to evaluate vascular opacification in each vascular segment of 5 age groups: ≤40 years (group 1), 41–60 years (group 2), 61–70 years (group 3), 71–75 years (group 4), and ≥76 years (group 5). Adequate vascular opacification was measured for attenuation in the suprarenal and infrarenal abdominal aorta and in the arteries of the lower extremity. Venous contamination was also measured. Results: Adequate vascular opacification from the suprarenal aorta to the level of the mid-popliteal artery was shown in all patients. Arterial opacification at the dorsalis pedis or plantar arteries was visualized in 85.7%–91.7% of patients and at the plantar arch arteries in 84.1%–91.7%. Minimal venous contamination was also shown adjacent to arterial enhancement, ranging from 0% to 28.6%. Conclusion: Performing CTA of the lower extremities with 64-slice MDCT could reduce the table speed to allow adequate arterial opacification and minimal venous contamination. [Copyright &y& Elsevier]

To date the anatomy of the intrapancreatic and peripancreatic veins using multidetector-row CT (MDCT) was not assessed. The object of this study is to establish 3D CT anatomy of these veins. A total of 100 consecutive patients who underwent abdominal triple-phase CT using 16-detector MDCT were retrospectively reviewed. The anatomical variations of the peripancreatic and intrapancreatic veins were assessed. Among the 100 cases, 42 cases (42%) had a single posterior superior pancreaticoduodenal vein crossing the ventral side of the common bile duct, while 30 cases (30%) had an uncinate vein running upward behind the medial side of the pancreatic. In the pancreatic head and body/tail area, there were many small veins that directly entered the superior mesenteric or splenic vein. In 59 cases (59%), the centro-inferior pancreatic vein ran transversely along the inferior surface of the pancreatic body and drained the anterior or inferior parts of the pancreatic body, mainly into the splenic vein. Many variations exist in the running patterns of intrapancreatic veins as well as peripancreatic veins. Recognition of abnormalities of intrapancreatic veins on CT in the light of normal CT anatomy may contribute to the interpretation of pathological conditions of the pancreas. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: The aim of this study was to assess the effects of radiation dose reduction on the assessment of the tracheal lumen on expiratory multidetector computed tomographic (MDCT) images of pediatric patients referred for evaluation for tracheomalacia (TM). Materials and Methods: The hospital information system was used to retrospectively identify 20 standard-dose and 20 reduced-dose paired inspiratory and expiratory MDCT studies performed for the evaluation of suspected TM in pediatric patients (aged ≤ 18 years). The reduced-dose technique used a 50% reduction of the tube current for the expiratory portion of the study compared to the standard-dose technique. Two experienced pediatric radiologists, who were blinded to the tube current of the study, reported their levels of confidence for measuring the tracheal lumen using a four-point scale ranging from zero (no confidence) to three (highest level of confidence). The difference in confidence level between the two groups of studies was analyzed using the Mann-Whitney U test. The percentage of radiation dose reduction using the reduced-dose technique in comparison to the standard-dose technique was estimated using anthropomorphic thorax phantoms. The presence or absence of TM (≥50% expiratory reduction in tracheal cross-sectional luminal area) on MDCT imaging was compared to bronchoscopic results for the subset of 32 patients who underwent both procedures. Results: A high level of confidence was reported for measuring the tracheal lumen on MDCT imaging for both standard-dose (median, 3.0) and reduced-dose (median, 3.0) expiratory sequences (P = .80). The total radiation dose of the paired inspiratory-expiratory computed tomographic (CT) exam was decreased by 23% with the reduced-dose technique. TM was diagnosed by CT imaging in seven patients who underwent standard-dose and six patients who underwent reduced-dose paired inspiratory and expiratory MDCT studies. CT results for the presence or absence of TM were concordant with the results of bronchoscopy in all 32 patients who underwent both procedures. Conclusion: The radiation dose of paired inspiratory-expiratory CT imaging can be reduced by 23% while maintaining similar diagnostic confidence for assessment of the tracheal lumen compared to a standard-dose technique in pediatric patients. Thus, a reduced-dose technique is recommended for evaluating TM in children. [Copyright &y& Elsevier]

Copyright of La Radiologia Medica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recently a 320-detector-row CT (MDCT) scanner has become available that allows axial volumetric scanning of a 16-cm-long range (50 cm field of view) in a single 0.35-s rotation. For imaging neonates and small children, volume scanning is potentially of great advantage as the entire scan range can be acquired in 0.35 s, which can reduce motion artefacts and may reduce the need for sedation in clinical CT imaging. Also, because there is no over-ranging associated with axial volumetric scanning, this may reduce patient radiation dose. To evaluate, by means of a phantom study, scan time and patient dose for thoracic imaging in neonates and small children by using axial cone-beam and helical fan-beam MDCT acquisitions. Paediatric imaging protocols were assessed for a 320-MDCT volumetric scanner (Aquilion ONE, Toshiba, Otawara, Japan). The 320-MDCT scanner allows for cone-beam acquisitions with coverage up to 160 mm, but it also allows for helical fan-beam acquisitions in 64-, 32-, or 16-MDCT modes. The acquisition configurations that were evaluated were 320 × 0.5 mm, 240 × 0.5 mm, and 160 × 0.5 mm for axial volumetric scanning, and 64 × 0.5 mm, 32 × 0.5 mm, and 16 × 0.5 mm for helical scanning. Dose assessment was performed for clinically relevant paediatric angiographic or chest/mediastinum acquisition protocols with tube voltages of 80 or 100 kVp and tube currents between 40 and 80 mA. Scan time was 0.35 s for 320-MDCT acquisitions, scan times varied between 1.9 s and 8.3 s for helical acquisitions. Dose savings varying between 18% and 40% were achieved with axial volumetric scanning as compared to helical scanning (for 320- versus 64-MDCT at 160 mm and 80 kVp, and for 320- versus 16-MDCT at 80 mm and 100 kVp, respectively). Statistically significant reduction in radiation dose was found for axial 320-MDCT volumetric scanning compared to helical 64-, 32-, and 16-MDCT scanning. Axial thoracic CT of neonates and small children with volumetric 320-MDCT can be performed between 5 and 24 times faster compared to helical scanning and can save patient dose. [ABSTRACT FROM AUTHOR]

Background: There are no reports regarding entire gastric fundic and esophageal varices evaluated with 64-row multidetector CT (MDCT). We attempt to clarify the feasibility of portal venography with this scanner in evaluation of these varices. Methods: A total of 33 patients, with clinically confirmed gastric fundic and esophageal varices secondary to posthepatitic cirrhosis, underwent thoracicoabdominal triphasic enhancement scans using 64-row MDCT along with conventional angiographic portography. CT portography and conventional portography were compared by statistical agreement to determine whether CT maximum intensity projection (CT-MIP) portography is useful in evaluation of entire gastric fundic and esophageal varices. Results: CT-MIP portography demonstrated gastric fundic and esophageal varices, and the inflowing and outflowing vessels of the varices. Gastric fundic varices were shown in 32 cases (97.0%), and esophageal varices were in 27 (81.8%). The inflowing vessels including the left gastric vein and posterior gastric vein/short gastric vein were illustrated in 31 (94.0%) and 17 (51.5%) cases, respectively. The outflowing vessels including the azygos vein, hemiazygos vein, and gastro-renal shunts were seen in 30 (90.9%), 8 (24.2%), and 12 (36.4%) cases, respectively. Findings of CT-MIP portography and conventional angiographic portography were in close agreement (Kappa value ranged from 0.621 to 1.000). Conclusion: CT-MIP venography with 64-row MDCT could be considered as a method for detecting entire gastric fundic and esophageal varices developed from posthepatitic cirrhosis. [ABSTRACT FROM AUTHOR]