Preoperative and postoperative evaluation of airways compression in pediatric patients with 3-dimensional multislice computed tomographic scanning: Effect on surgical management

ObjectivesSurgical management of airway compression of vascular origin requires an accurate analysis of anatomy and various mechanisms of compression. This study assessed the usefulness of 3-dimensional computed tomographic scanning in the preoperative and postoperative evaluation of airways compression in a pediatric population.MethodsThirty-seven consecutive patients (median age, 4 months) were examined with multislice 3-dimensional computed tomographic scanning: 18 patients before surgical treatment of anomalies of vascular rings, 2 patients because of respiratory symptoms after repair of esophageal atresia, and 17 patients because of persisting respiratory symptoms or prolonged mechanical ventilation after cardiac surgery for congenital heart disease.ResultsThe procedure was successful, with high-quality diagnostic imaging obtained in all cases without any complications. The anatomy and relationship between the vascular arches and airways was analyzed in all referred patients with vascular arch anomalies confirmed on the basis of the surgical findings, and this helped the surgeon to plan the procedure and choose the best approach. After cardiac surgery, the airway and vascular structures involved and the mechanism of compression were specified in all but one case, and the 3-dimensional computed tomographic scan serves as an important tool for deciding whether to perform reoperation on patients requiring prolonged mechanical ventilation.ConclusionThree-dimensional computed tomographic scanning is a safe, fast, and noninvasive method useful for accurately analyzing the mechanisms of airway compression of vascular origin and thus possible improving the surgical management of pediatric patients

Non-Invasive Detection of Coronary Artery Disease in Patients With Left Bundle Branch Block Using 64-Slice Computed Tomography

ObjectivesThe goal of this study was to evaluate the diagnostic accuracy of 64-slice computed tomography (CT) to identify coronary artery disease (CAD) in patients with complete left bundle branch block (LBBB).BackgroundLeft bundle branch block increases risk of cardiac mortality, and prognosis is primarily determined by the underlying coronary disease. Non-invasive stress tests have limited performance, and conventional coronary angiography (CCA) is usually required.MethodsSixty-six consecutive patients with complete LBBB and sinus rhythm admitted for CCA were enrolled. Computed tomography was performed 3 ± 3.9 days before CCA. The accuracy of 64-slice CT to detect significant stenosis (>50% lumen narrowing) was compared with quantitative coronary angiography. All segments were analyzed regardless of image quality from coronary calcification or motion artifacts. Results were analyzed by patient and by coronary segment (990) using the American Heart Association 15-segment model.ResultsLower heart rates were associated with improved image quality. Computed tomography correctly identified 35 of 37 (95%) patients without significant stenosis and 28 of 29 (97%) patients with significant stenosis on CCA. Computed tomography correctly assessed 68 of 94 (72%) significant stenosis. Overall, accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 64-slice CT for identifying CAD by patient was 95%, 97%, 95%, 93%, and 97%, respectively, and by segment was 97%, 72%, 99%, 91%, and 97%, respectively.ConclusionsIn a routine clinical practice, 64-slice CT detects with excellent accuracy a significant CAD in patients with complete LBBB. A normal CT in this clinical setting is a robust tool to act as a filter and avoid invasive diagnostic procedures

The Image Quality and Radiation Dose of 100-kVp versus 120-kVp ECG-Gated 16-Slice CT Coronary Angiography

Objective: This study was conducted to assess the feasibility of performing 100-kVp electrocardiogram (ECG)-gated coronary CT angiography, as compared to 120-kVp ECG-gated coronary CT angiography. Materials and Methods: We retrospectively evaluated one hundred eighty five gencler- and body mass index-matched 16-slice coronary CT sets of data, which were obtained using either 100 kVp and 620 effective mAs or 120 kVp and 500 effective mAs. The density measurements (image noise, vessel density, signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]) and the estimated radiation dose were calculated. As a preference test, two image readers were independently asked to choose one image from each pair of images. The results of both protocols were compared using the paired t-test or the Wilcoxon signed rank test. Results: The 100-kVp images showed significantly more noise and a significantly higher vessel density than did the 120-kVp images. There were no significant differences in the SNR and CNR. The estimated reduction of the radiation dose for the 100-kVp protocol was 24%; 7.8 +/- 0.4 mSV for 1 00-kVp and 10.1 +/- 1.0 mSV for 120-kVp (p < 0.001). The readers preferred the 1 00-kVp images for reading (reader 1, p = 0.01; reader 2, p = 0.06), with their preferences being stronger when the subject`s body mass index was less than 25. Conclusion: Reducing the tube kilovoltage from 120 to 100 kVp allows a significant reduction of the radiation dose without a significant change in the SNR and the CNR.Stolzmann P, 2008, RADIOLOGY, V249, P71, DOI 10.1148/radiol.2483072032Earls JP, 2008, RADIOLOGY, V246, P742, DOI 10.1148/radiol.2463070989Stolzmann P, 2008, EUR RADIOL, V18, P592, DOI 10.1007/s00330-007-0786-8Schoenhagen P, 2008, EUR HEART J, V29, P153, DOI 10.1093/eurheartj/ehm614Heyer CM, 2007, RADIOLOGY, V245, P577, DOI 10.1148/radiol.2452061919Paul JF, 2007, EUR RADIOL, V17, P2028, DOI 10.1007/s00330-007-0584-3McCollough CH, 2007, RADIOLOGY, V243, P775, DOI 10.1148/radiol.2433061165Schueller-Weidekamm C, 2006, RADIOLOGY, V241, P899, DOI 10.1148/radiol.2413040128Hsieh J, 2006, MED PHYS, V33, P4236, DOI 10.1118/1.2361078d`Agostino AG, 2006, EUR RADIOL, V16, P2137, DOI 10.1007/s00330-006-0218-1Hohl C, 2006, EUR RADIOL, V16, P1841, DOI 10.1007/s00330-005-0124-yJohnson TRC, 2006, EUR RADIOL, V16, P1409, DOI 10.1007/s00330-006-0298-yAbada HT, 2006, AM J ROENTGENOL, V186, pS387, DOI 10.2214/AJR.05.0216Hausleiter J, 2006, CIRCULATION, V113, P1305, DOI 10.1161/CIRCULATIONAHA.105.602490NAKAYAMA Y, 2006, AM J ROENTGENOL, V187, pW490Ghersin E, 2006, AM J ROENTGENOL, V186, P177, DOI 10.2214/AJR.04.1232Haberl R, 2005, AM HEART J, V149, P1112, DOI 10.1016/j.ahj.2005.02.048Wintersperger B, 2005, EUR RADIOL, V15, P334, DOI 10.1007/s00330-004-2575-ySigal-Cinqualbre AB, 2004, RADIOLOGY, V231, P169, DOI 10.1148/radiol.2311030191Kalra MK, 2004, RADIOLOGY, V230, P619, DOI 10.1148/radiol.2303021726Jung B, 2003, EUR RADIOL, V13, P2560, DOI 10.1007/s00330-003-2111-5Jakobs TF, 2002, EUR RADIOL, V12, P1081, DOI 10.1007/s00330-001-1278-xHuda W, 2000, RADIOLOGY, V217, P430Kalender WA, 1999, EUR RADIOL, V9, P3231

3D modeling and printing in large native right ventricle outflow tract to plan complex percutaneous pulmonary valve implantation

Objective: Investigating accuracy of cardiac tomography (CT) derived post-processing3D reconstruction (CT-PPR) and 3D printing to predict percutaneous pulmonary valve implantation (PPVI) feasibility. Background: PPVI feasibility remains challenging in large native regurgitant right ventricle outflow tract (RVOT). Methods: Fifteen patients with large native RVOT were investigated. CT-PPR consisted in RVOT long-axis curvilinear reconstruction (LACR) to measure the landing zone (LZ), and 3D volume rendering for morphological evaluation. A STL was generated to create 3D printed model (flexible resin). Balloon sizing was subsequently performed to measure LZ diameter (3D-MBD), compared to invasive balloon diameter (IBD) during catheterization, considered as the Gold Standard. Two operators predicted the feasibility of PPVI using CT-PPR and 3D printed models independently and blinded to outcome. Results: On 3D printed models, RVOT shape was tubular in 5 patients, divergent in 5 patients, concave in 4 patients and convergent in one. Agreement with CT-PPR RVOT shape morphology assessment was observed in 93% of cases (Kappa coefficient 0.91, p < 0.0001). Minimal IBD was 26.0 [24.4–27.9] mm. Minimal LZ LACR diameters were well correlated to IBD (Spearman rho = 0.67, p = 0.007; r2 = 0.55, p = 0.002) with a mean underestimation bias of 2.8 mm. Minimal 3D-MBD was correlated to IBD (Spearman rho = 0.55, p = 0.04, r2 = 0.50, p = 0.003) with mean underestimation bias of 0.9 mm.PPVI was successful and uneventful in 11 patients, challenging in one and non-feasible in 3. Using CT-PPR and 3D printed models, interventionists predictions agreement with outcome was 93% and 87% (Kappa coefficient = 0.86, p = 0.0001, and Kappa coefficient = 0.65, p = 0.0007 respectively). Conclusion: RVOT 3D CT-PPR and printing allow reliable assessment of RVOT shape and LZ diameter prior to PPVI. Prediction of PPVI feasibility in challenging cases is facilitated