Ummugulsum Bayraktutan

Alveolar Echinococcosis: Spectrum of Findings at Cross-sectional Imaging

Alveolar echinococcosis is a rare parasitic disease caused by the fox tapeworm Echinococcus multilocularis, which is endemic in many parts of the world. Without timely diagnosis and therapy, the prognosis is dismal, with death the eventual outcome in most cases. Diagnosis is usually based on findings at radiologic imaging and in serologic analyses. Because echinococcal lesions can occur almost anywhere in the body, familiarity with the spectrum of cross-sectional imaging appearances is advantageous. Echinococcal lesions may produce widely varied imaging appearances depending on the parasites growth stage, the tissues or organs affected, and the presence of associated complications. Although the liver is the initial site of mass infestation by E multilocularis, the parasite may disseminate from there to other organs and tissues, such as the lung, heart, brain, bones, and ligaments. In severe infestations, the walls of the bile ducts and blood vessels may be invaded. Disseminated parasitic lesions in unusual locations with atypical imaging appearances may make it difficult to narrow the differential diagnosis. Ultrasonography, computed tomography (CT), magnetic resonance (MR) imaging with standard and diffusion-weighted sequences, and MR cholangiopancreatography all provide useful information and play complementary roles in detecting and characterizing echinococcal lesions. Cross-sectional imaging is crucial for differentiating echinococcosis from malignant processes: CT is most useful for depicting the peripheral calcifications surrounding established echinococcal cysts, and MR imaging is most helpful for identifying echinococcosis of the central nervous system.

Diagnostic performance of diffusion-weighted MR imaging in detecting acute appendicitis in children: Comparison with conventional MRI and surgical findings

To determine the value of diffusion‐weighted MRI for the diagnosis of acute appendicitis in children.

Congenitally corrected transposition of the great arteries: MDCT angiography findings and interpretation of complex coronary anatomy

A 56-year-old male patient was admitted to our hospital because of dyspne and chest pain. A chest radiograph showed mild cardiomegaly. Echocardiography revealed unusual chamber in the heart. The chamber beneath the left atrium was morphologically right ventricle. To evaluate the precise complex anatomy of this abnormality, multidetector computed tomography (MDCT) angiography was performed. MDCT clearly revealed complex intracardiac and vascular anatomy, including typical imaging findings of a patient with congenitally corrected transposition of the great arteries (CCTGA). We described both imaging findings of MDCT angiography and interpretation of complex vascular anatomy in a patient with CCTGA.

Follow-up of coronary artery bypass graft patency: diagnostic efficiency of high-pitch dual-source 256-slice MDCT findings.

Objectives Our aim was to evaluate the diagnostic accuracy of 256-slice, high-pitch mode multidetector computed tomography (MDCT) for coronary artery bypass graft (CABG) patency. Methods Eighty-eight patients underwent 256-slice MDCT angiography to evaluate their graft patency after CABG surgery using a prospectively synchronized electrocardiogram in the high-pitch spiral acquisition mode. Effective radiation doses were calculated. We investigated the diagnostic accuracy of high-pitch, low-dose, prospective, electrocardiogram-triggering, dual-source MDCT for CABG patency compared with catheter coronary angiography imaging findings. Results A total of 215 grafts and 645 vessel segments were analyzed. All graft segments had diagnostic image quality. The proximal and middle graft segments had significantly (P < 0.05) better mean image quality scores (1.18 ± 0.4) than the distal segments (1.31 ± 0.5). Using catheter coronary angiography as the reference standard, high-pitch MDCT had the following sensitivity, specificity, positive predictive value, and negative predictive value of per-segment analysis for detecting graft patency: 97.1%, 99.6%, 94.4%, and 99.8%, respectively. Conclusions In conclusion, MDCT can be used noninvasively with a lower radiation dose for the assessment of restenosis in CABG patients.

Diagnostic performance of multidetector computed tomography for detecting aorto-ostial lesions compared with catheter coronary angiography: multidetector computed tomography coronary angiography is superior to catheter angiography in detection of aorto-ostial lesions.

Purpose: In this study, our goal is to determine the use of multidetector computed tomography (MDCT) in detection of aorto-ostial lesions. Materials and Methods: Thirty-three patients suspected to have aorto-ostial lesion by either catheter angiography (CA) or MDCT coronary angiography comprised our study population. In 19 patients (group 1), aorto-ostial lesion was suspected based on CA, then MDCT coronary angiography was performed. In the remaining 14 patients (group 2), aorto-ostial lesion diagnosis was made by MDCT coronary angiography, and then afterward, CA was performed. A cardiologist and a radiologist reevaluated both the CA and MDCT coronary angiography recordings of all patients and their consensus formed the diagnosis. We accepted this consensus diagnosis as our criterion standard because a universal criterion standard to compare CA and MDCT findings with is not available. Then, the previous diagnoses by CA and MDCT coronary angiography were compared with the consensus diagnoses. Results: Finally, 26 patients were diagnosed with aorto-ostial lesion, whereas 5 patients were found not to have aorto-ostial lesions. Two patients were diagnosed with abnormal origination of a coronary artery. When the results were evaluated in terms of the presence of aorto-ostial lesion, MDCT coronary angiography correctly diagnosed all 26 patients, and in the 5 patients with normal ostium, MDCT coronary angiography finding was also normal. However, 7 of 26 patients with aorto-ostial lesion were reported to be normal by CA, and also 5 patients with normal ostia were reported to have aorto-ostial lesion by CA. That is, 12 of 33 patients were misdiagnosed by CA. Moreover, CA missed the abnormal origination of the coronary arteries in 2 patients. When the results were evaluated in terms of the degree of stenosis in 26 patients with aorto-ostial lesion; MDCT coronary angiography predicted the final diagnosis in all 26 patients correctly. However, CA predicted the final degree of stenosis only in 12 patients. Catheter angiography underestimated the degree of the stenosis in 2 patients, overestimated in 5 patients and missed the lesion in 7 patients. Conclusions: Our findings suggest that MDCT is a reliable tool for diagnosing the presence and severity of aorto-ostial lesions. In addition, MDCT might be useful in preventing the false diagnosis due to the catheter-induced spasms in patients who were diagnosed with aorto-ostial lesion by CA. Moreover, if MDCT coronary angiography detects a lesion in aorto-ostial region, there is no need to perform CA to merely verify this pathology.

Ultrasound-guided shoulder MR arthrography: comparison of rotator interval and posterior approach

PURPOSE The purpose of this study was to prospectively evaluate the two different ultrasound-guided injection techniques for magnetic resonance (MR) arthrography of the shoulder. METHODS AND MATERIALS This study included 100 patients [50 rotator interval group (n=50) vs. 50 posterior approach group (n=50)]. All procedures were performed by the same radiologist. The two injection techniques were compared. The discomfort during and after arthrography was evaluated. Extraarticular contrast media extravasation was graded according to the MRI findings. The number of injection attempts, effect of contrast media extravasation rate on diagnostic quality and procedure times were recorded. RESULTS There were no significant difference between the posterior and rotator interval puncture groups with regard to pain (P=.915), procedure times (P=.401) or attempt scores (P=.182). There were significantly more contrast media extravasations with rotator interval approach than posterior approach (P<.05). CONCLUSION Both techniques were successful and well tolerated by patients. Posterior injection technique provided a more effective route with decreased extravasation rate and easier approach compared to the rotator interval approach.

Effect of the reconstruction window obtained at the isovolumic relaxation period on the image quality in electrocardiographic-gated 16-multidetector-row computed tomography coronary angiography studies

Objective: To evaluate whether images obtained during the reconstruction window responding to the isovolumic relaxation period could be used for rapid and easy postprocessing. Methods: One hundred ten consecutive patients with suspected coronary artery disease who had previously had a multidetector computed tomography (MDCT) scan for imaging coronary arteries were enrolled in this study. The age of the patients was 59 ± 13 years (range: 33-78 years), and 77 (70%) were male. Multidetector computed tomography was performed on a 16-detector-row computed tomography scanner during 1 breath hold (16-24 seconds). Seven different sets of images reconstructed at every 10% of the R-R interval from 30% to 90% for contrast-enhanced scans at levels containing the first several centimeters of the left and right coronary arteries were analyzed. The best of these reconstruction windows were then compared with the images reconstructed at the isovolumic relaxation period, which is the last portion of the T wave at the end of the systole, where there is not any change in ventricular volume, which causes stepladder artifacts. The step artifact was classified as excellent, good, or poor. Image quality was assessed by 2 radiologists who were not aware of each others interpretation. Results: According to the routinely used reconstructions, there were 76 patients with excellent image quality, 28 with good image quality, and 6 with poor image quality. For the period of isovolumic relaxation, there were 74 patients with excellent image quality, 25 with good image quality, and 11 with poor image quality. Conclusion: If one begins image analysis with the isovolumic relaxation period reconstruction window, spending less time for postprocessing analyses, good image quality can be obtained such as with other good reconstruction windows.

Abdominal Perfusion Computed Tomography

The purpose of this article is to provide an up to date review on the spectrum of applications of perfusion computed tomography (CT) in the abdomen. New imaging techniques have been developed with the objective of obtaining a structural and functional analysis of different organs. Recently, perfusion CT has aroused the interest of many researchers who are studying the applicability of imaging modalities in the evaluation of abdominal organs and diseases. Per-fusion CT enables fast, non-invasive imaging of the tumor vascular physiology. Moreover, it can act as an in vivo biomarker of tumor-related angiogenesis.

Efficacy of ivabradin to reduce heart rate prior to coronary CT angiography: comparison with beta-blocker

PURPOSE The objective of our study was to assess the effect of ivabradine on image quality of ECG-gated multidetector computed tomography (MDCT) coronary angiography. MATERIALS AND METHODS Computed tomography coronary angiography (CTCA) was performed on two groups. In Group 1 (n=54), an intravenous beta-blocker was administered to patients with a heart rate >70 beats per minute (bpm) just before CTCA. In Group 2 (n=56), oral ivabradine 5 mg was administered twice a day for three days prior to CTCA examination to patients with a heart rate >70 bpm and contraindication to beta-blockers. Images acquired on two different MDCT scanners were scored in terms of image quality of the coronary artery segments using a 5-point grading scale (Grade 1, unreadable; Grade 5, excellent). RESULTS The mean heart rates during CTCA were 64 ± 6.7 bpm for Group 1 and 59 ± 4.1 bpm for Group 2 (P < 0.05). Mean heart rate reduction was 9 ± 5% and 14 ± 8% for Groups 1 and 2, respectively (P < 0.001). A total of 880 segments were evaluated in 110 patients. When the best reconstruction interval was used, 89.8% and 95.5% of all the coronary segments showed acceptable image quality in Groups 1 and 2, respectively. Acceptable image quality of the middle right coronary artery was obtained in 78.3% of Group 1 and 92.4% of Group 2. These ratios for the other segments were 88.4% for Group 1 and 95.2% for Group 2. CONCLUSION Reduction of heart rates with ivabradine premedication improves the image quality of CTCA. It should be considered as an alternative drug, particularly in patients with contraindications to beta-blockers.

Magnetic Resonance Arthrography of the Glenohumeral Joint: Ultrasonography-Guided Technique Using a Posterior Approach

OBJECTIVE The purpose of this study was to assess the efficacy and feasibility of ultrasound (US)-guided magnetic resonance (MR) arthrography of the glenohumeral joint via a posterior approach. MATERIALS AND METHODS Thirty-four patients (18 males and 16 females) who were suspected to have glenohumeral joint pathology were examined using MR arthrography. The patients ranged in age from 21 to 85 years, and the average age was 45±15.9 years. A Toshiba Xario US unit was utilized. Ultrasonography examinations were conducted using a broad-band 5-12 MHz linear array transducer. Gadolinium was injected into the shoulder joint using an 18-20 gauge needle. MR imaging was performed within the first 30 min after the injection. RESULTS The injection of gadolinium into the shoulder joint was successfully accomplished in all 34 patients. Major contrast media extravasation outside the joint was depicted in only two patients (5.9%). No major complications were encountered. CONCLUSION Ultrasonography is an effective alternate guidance technique for the injection of gadolinium into the glenohumeral joint for MR arthrography. US-guided arthrography via a posterior approach to the glenohumeral joint is safe, accurate, well tolerated by patients and easy to perform with minimal training.