Multidetector-row Computed Tomography Angiography Research Articles

Carotid Plaque Enhancement and Symptom Correlations: An Evaluation by Using Multidetector Row CT Angiography

The identification of plaque characteristics that determine its vulnerability is extremely important. The purpose of this work was to evaluate CPE after administration of contrast material and to assess whether there is a statistical association between CPE and cerebrovascular symptoms. Ninety-seven consecutive patients (69 men, 28 women; mean age, 62 years; age range, 39-82 years), studied by using an MDCT scanner, were retrospectively analyzed. Examinations were performed before and after administration of contrast medium. Plaque enhancement was analyzed, and the obtained data were compared with the patient's symptoms. Patients were classified as symptomatic (TIA or stroke with a temporal window of 6 months) or asymptomatic according to neurologic assessment and the TOAST criteria. The ROC curve and Az were calculated, and multiple logistic regression analysis was performed. Thirty-nine patients were excluded because they had calcified plaques (40.2%). CPE was observed in 74% of the remaining 58 patients. A statistically significant difference was observed between symptomatic and asymptomatic patients for the presence of CPE (P = .0013; OR = 7.5). Moreover, we observed that CPE was higher in fatty plaques (P = .035) than in mixed ones and more frequent in the former (P = .0119). The ROC curve demonstrated that a threshold of 15 HU is associated with a specificity and sensitivity of 83.33% and 76.47%, respectively. Multiple logistic regression showed that CPE and symptoms are associated (P = .0315). The results of our study suggest that for noncalcified carotid plaques, the presence of CPE is associated with cerebrovascular symptoms. Fatty plaques are more likely to have CPE compared with mixed plaques.

Optimal iodine dose for 3-dimensional multidetector-row CT angiography of the liver

PurposeTo clarify the optimal iodine dose of contrast material for 3-dimensional multidetector-row CT angiography (3D-MDCTA) of the venous vasculature of the liver using volume rendering technique. Materials and methodsThis study included 103 patients who were randomly assigned to 5 contrast-enhanced MDCT protocol groups with different body-weight-tailored doses of contrast material: 500, 600, 630, 650, and 700mgI/kg body weight. The arterial, portal, and hepatic parenchymal phases were obtained to evaluate enhancement values of the aorta, portal vein, and hepatic vein. Visualization of the portal and hepatic veins on the volume-rendering images of 3D-MDCTA was evaluated using a 5-point grade. Dunnett's test was used to compare the mean enhancement value and mean grades of image quality (700mgI/kg dose group was control). ResultsThe mean enhancement values of portal and hepatic vein in the group with 500 and 600mgI/kg were significantly lower than those of the control group. During visual assessment, a significantly lower mean grades were observed in 500mgI/kg groups for the portal vein, and 500 and 600mgI/kg groups for hepatic vein. There were no significant intergroup differences in mean enhancement values and visual assessment among the groups using 630mgI/kg or more. ConclusionIodine doses of 630mgI/kg was recommended for 3D-MDCTA.

The multidetector computed tomography angiography (MDCTA) in the diagnosis of splenic artery aneurysm and pseudoaneurysm

Splenic artery aneurysm is the most frequent visceral artery aneurysm and rupture of the aneurysm is associated with a high mortality rate. It is important to discriminate between a true aneurysm and a pseudoaneurysm that may be caused by pancreatitis, iatrogenic and postoperative causes, trauma and peptic ulcer disease. Multidetector-row CT angiography (MDCTA) allows detailed visualization of the vascular anatomy and may allow identification of aneurysms and pseudoaneurysms that affect the splenic artery. The objective of this article is to provide a review of the general characteristics of splenic artery aneurysms and pseudoaneurysms and to describe the findings of MDCTA.

Pulmonary Emphysematous Changes in Patients with Congenital Heart Disease Associated with Increased Pulmonary Blood Flow: Evaluation Using Multidetector-Row Computed Tomography

The present study aimed to evaluate the prevalence and the location of segmental emphysematous change in congenital heart disease (CHD) patients with increased pulmonary blood flow using multidetector-row computed tomography (MDCT). A total of 129 consecutive patients (mean age, 5.8±5.4 years; range, 1 month to 24 years) underwent MDCT angiography of the thorax. The frequency of emphysematous change was evaluated in patients with ventricular septal defect (VSD, n=61), atrial septal defect (ASD, n=27), patent ductus arteriosus (PDA, n=36) and complete atriventriclar septal defect (CAVSD, n=5). In 59 patients who underwent cardiac catheterisation, the relationships between the emphysematous change and both pulmonary to systemic blood flow ratio (Qp/Qs) and mean pulmonary arterial pressure (mPAP) were evaluated. The emphysematous change was detected in 57 patients (44.2%) out of 129 patients. The frequency of segmental emphysematous change in left side was higher than in right side (14.8% vs. 6.5%). Both Qp/Qs and mPAP affected the presence of emphysema. MDCT can provide accurate detection of segmental emphysema in patients with CHD. Emphysematous change is not uncommon pathological lesion in children and adolescents with CHD.

Analysis of deep inferior epigastric perforator (DIEP) arteries by using MDCTA: Comparison between 2 post-processing techniques

Our purpose was to compare two post-processing techniques, Maximum-Intensity-Projection (MIP) and Volume Rendering (VR) for the study of perforator arteries. Thirty patients who underwent Multi-Detector-Row CT Angiography (MDCTA) between February 2010 and May 2010 were retrospectively analyzed. For each patient and for each reconstruction method, the image quality was evaluated and the inter- and intra-observer agreement was calculated according to the Cohen statistics. The Hounsfield Unit (HU) value in the common femoral artery was quantified and the correlation (Pearson Statistic) between image quality and HU value was explored. The Pearson r between the right and left common femoral artery was excellent (r=0.955). The highest image quality score was obtained using MIP for both observers (total value 75, with a mean value 2.67 for observer 1 and total value of 79 and a mean value of 2.82 for observer 2). The highest agreement between the two observers was detected using the MIP protocol with a Cohen kappa value of 0.856. The ROC area under the curve (Az) for the VR is 0.786 (0.086 SD; p value=0.0009) whereas the ROC area under the curve (Az) for the MIP is 0.0928 (0.051 SD; p value=0.0001). MIP showed the optimal inter- and intra-observer agreement and the highest quality scores and therefore should be used as post-processing techniques in the analysis of perforating arteries.

Radiation Exposure to Patients in a Multicenter Coronary Angiography Trial (CORE 64)

The objective of this study was to assess the exposure of patients to radiation for the cardiac CT acquisition protocol of the multicenter Coronary Artery Evaluation Using 64-Row Multidetector Computed Tomography Angiography (CORE 64) trial. An algorithm for patient dose assessment with Monte Carlo dosimetry was developed for the Aquilion 64-MDCT scanner. During the CORE 64 study, different acquisition protocols were used depending on patient size and sex; therefore, six patient models were constructed representing three men and three women in the categories of small, normal size, and obese. Organ dose and effective dose resulting from the cardiac CT protocol were assessed for these six patient models. The average effective dose for coronary CT angiography (CTA) calculated according to Report 103 of the International Commission on Radiological Protection (ICRP) is 19 mSv (range, 16-26 mSv). The average effective dose for the whole cardiac CT protocol including CT scanograms, bolus tracking, and calcium scoring is slightly higher-22 mSv (range, 18-30 mSv). An average conversion factor for the calculation of effective dose from dose-length product of 0.030 mSv/mGy · cm was derived for coronary CTA. The current methods of assessing patient dose are not well suited for cardiac CT acquisitions, and published effective dose values tend to underestimate effective dose. The effective dose of cardiac CT is approximately 25% higher when assessed according to the preferred ICRP Report 103 compared with ICRP Report 60. Underestimation of effective dose by 43% or 53% occurs in coronary CTA according to ICRP Report 103 when a conversion factor (E / DLP, where E is effective dose and DLP is dose-length product) for general chest CT of 0.017 or 0.014 mSv/mGy · cm, respectively, is used instead of 0.030 mSv/mGy · cm.

The Significance of the Circumaortic Left Renal Vein and Other Venous Variations in Laparoscopic Living Donor Nephrectomies

Among the several vascular variation those concerning the venous system of the kidneys show the most significant variability. They often play an important role when it comes to choosing the kidney to be removed for transplantation. Based on our prior studies, we have surveyed these variations. When performing a laparoscopic living donor nephrectomy owing to the limited field of vision and the restricted possibilities for preparation, preoperative radiologic planning is of utmost importance. We evaluated 55 donors who underwent laparoscopic nephrectomies using the 16-section multidetector-row computed tomography angiography. Among the donors who underwent surgeries we observed circumaortic veins (CAV) in three cases, retroaortic veins in 6 cases, multiple renal veins in 10 cases, and a lumbar vein draining into the left renal vein (RV) in 30 cases. In the 2 cases wherein CAVs were discovered, the team decided to use the other kidney. In 1 case, due to a short right RV, we chose the left kidney. The complex development of the CAV that is sometimes difficult to reconstruct in 3D poses a challenge for both the radiologist and the surgeon.

The Efficacy of Preoperative Vascular Mapping by MDCTA in Selecting Flap in Abdominal Flap Breast Reconstruction

Current methods of breast reconstruction using abdominal tissue include the transverse abdominal myocutaneous (TRAM) flap, deep inferior epigastric arterial perforator (DIEP) flap, superficial inferior epigastric arterial (SIEA) flap, and some other composite flaps. Because of the variant vascular anatomy in abdominal region, it is hard to choose an appropriate flap for a specific patient without accurate preoperative vascular mapping. This study was drawn to address the efficacy of preoperative vascular mapping by multidetector-row computed tomographic angiography (MDCTA) in selecting flap in abdominal flap breast reconstruction. A total of 34 breast reconstructions using abdominal flap from December 2006 to July 2009 were included. In all the patients included, MDCTA was performed preoperatively. Three indexes were obtained including choice of flaps, operation time, and flap complication rate. Then, these data were compared with the former data stored in the databank of our hospital from January 2004 to December 2006, before MDCTA was introduced in our center. Among the 34 patients, the flap selection was: SIEA flaps 11.8%, DIEP flaps 61.8%, TRAM flaps 11.8%, and bilateral flaps 14.7%. The correlate indexes from the data bank were as follows: SIEA flap 0; DIEP flaps 51.7%; TRAM flaps 32.8%; bilateral flaps 15.5%. p < 0.05 occurred between the comparison of SIEA, DIEP, and TRAM flap choice in the two groups. The operation time in the study group was as follows: SIEA flap (4.02 ± 0.46) hours, DIEP flap (6.23 ± 1.42) hours, TRAM flap (4.72 ± 1.53) hours, Bilateral flap (7.86 ± 1.16) hours; while the former correlate data were: DIEP (9.67 ± 1.74) hours, TRAM flap (6.64 ± 1.83) hours, bilateral flap (11.83 ± 1.35) (all the three comparison p < 0.05). The total flap complication rate was about 5.9% in the test group; while in the databank, it was 12.1% (p < 0.05). With the accurate mapping of vascular territory in abdomen by MDCTA, we could easily select a suitable abdominal flap for breast reconstruction, and we can also simplify the procedure to save operation time and make the process more safely.

Comparison between Carotid Artery Wall Thickness Measured by Multidetector Row Computed Tomography Angiography and Intimae-Media Thickness Measured by Sonography

The increased thickness of the carotid wall >1 mm is a significant predictor of coronary and cerebrovascular diseases. The purpose of our study was to assess the agreement between multidetector row computed tomography angiography (MDCTA) in measuring carotid artery wall thickness (CAWT) and color Doppler ultrasound (CD-US) in measuring intimae-media thickness (IMT). Eighty-nine patients (aged 35–81) were prospectively analyzed using a 64-detector MDCTA and a CD-US scanner. Continuous data were described as the mean value ± standard deviation, and were compared using the Mann–Whitney U test. A p value <0.05 was considered significant. Bland–Altman statistics were employed to measure the agreement between MDCTA and CD-US. CAWT ranged from 0.62 to 1.60 mm, with a mean value of 1.09 mm. IMT ranged from 0.60 to 1.55 mm, with a mean value of 1.06 mm. We observed an excellent agreement between CD-US and MDCTA in the evaluation of the common carotid artery thickness, with a bias between methods of 0.029 mm (which is a highly statistically important difference of absolute values [t = 43.289; p < 0.01] obtained by paired T test), and limits of agreement from 0.04 to 0.104. Pearson correlation coefficient was 0.9997 (95% CI 0.9996–0.9998; p < 0.01). We conclude that there is an excellent correlation between CAWT and IMT measurements obtained with the MDCTA and CD-US.

Multidetector computed tomographic angiography evaluation of micropig major systemic vessels for xenotransplantation

Due primarily to the increasing shortage of allogeneic donor organs, xenotransplantation has become the focus of a growing field of research. Currently, micropigs are the most suitable donor animal for humans. However, no standard method has been developed to evaluate the systemic vascular anatomy of micropigs and standard reference values to aid in the selection of normal healthy animals as potential organ donors are lacking. Using 64-channel multidetector row computed tomographic angiography (MDCTA), we evaluated morphological features of the major systemic vessels in micropigs and compared our results to published human data. The main vasculature of the animals was similar to that of humans, except for the iliac arterial system. However, diameters of the major systemic vessels were significantly different between micropigs and humans. Specifically, the diameter of the aortic arch, abdominal aorta, external iliac artery, and femoral artery, were measured as 1.50 ± 0.07 cm, 0.85 ± 0.06 cm, 0.52 ± 0.05 cm, and 0.48 ± 0.05 cm, respectively, in the micropigs. This MDCTA data for micropig major systemic vessels can be used as standard reference values for xenotransplantation studies. The use of 64-channel MDCTA enables accurate evaluation of the major systemic vasculature in micropigs.

Multidetector-Row CT Angiography of Cerebral Vasospasm after Aneurysmal Subarachnoid Hemorrhage: Comparison of Bone Subtraction and Standard CT Angiography with Digital Subtraction Angiography

Copyrights © 2011 The Korean Society of Radiology Purpose: To evaluate the usefulness of multidetector-row CT angiography (MDCTA) for the diagnosis of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) by comparison of digital subtraction angiography (DSA) and to compare the bone subtraction CT angiography (BS-CTA) and standard CT angiography (S-CTA). Materials and Methods: Thirty-three patients who were treated with intraarterial nimodipine infusion for the cerebral vasospasm after aneurysmal SAH were evaluated with MDCTA and DSA. BS-CTA images were reconstructed from the S-CTA and unenhanced CT source images. A total of 207 vascular segments were evaluated. A fourstep scale for the degree of stenosis was applied for each segment. With DSA as the standard images, BS-CTA and S-CTA images were comparied. Results: On DSA, 56 segments (27%) presented vasospasm. Concordance between the DSA and S-CTA and between DSA and BS-CTA were 94.7% and 82.1%, respectively. Overestimation for the degree of stenosis was shown in 37 segments on BS-CTA and in 8 segments on S-CTA, but underestimated segments were only shown on SCTA (n = 4). Conclusion: MDCTA with standard technique seems to be a useful imaging tool for the evaluation of the cerebral vasospasm after aneurysmal SAH. However, BS-CTA is not needed because of additional radiation and overestimation of the degree of stenosis. Index terms Intracranial Aneurysm Subarachnoid Hemorrhage Vasospasm, Intracranial Cerebral Angiography Tomography, X-Ray Computed Multidetector-Row CT Angiography of Cerebral Vasospasm after Aneurysmal Subarachnoid Hemorrhage: Comparison of Bone Subtraction and Standard CT Angiography with Digital Subtraction Angiography 동맥류성 거미막밑출혈 후 발생한 뇌혈관 연축의 다중검출기 CT 혈관조영술: 골감산 및 표준기법의 CT 혈관조영술과 디지털감산혈관조영술의 비교

Multi-Detector Row Computed Tomography Angiography of the Aorta

No cabe duda que la angiotomografia computarizada con tomografos multidetectores (angio-TCMD) se ha convertido en el metodo de eleccion para la evaluacion del espectro de la patologia aortica, gracias a su gran capacidad multiplanar, disponibilidad y eficacia. Con frecuencia, la sintomatologia de los pacientes con sindrome aortico agudo es poco especifica y, de hecho, puede simular otros tipos de patologia toracica. Por lo tanto, se requiere un metodo de imagen que, por su naturaleza integral, permita la evaluacion no solamente de la aorta, sino de otras estructuras toracicas, e incluso abdominales, en un periodo relativamente corto. Como ejemplo, se puede citar el “descarte triple” (Triple Rule-Out) donde, en un solo barrido tomografico, es posible evaluar los territorios vasculares pulmonares, aorticos y coronarios, en adicion al parenquima pulmonar y pared toracica. En la decada de los noventa y con el desarrollo de la TC helicoidal fue posible obtener imagenes continuas mientras el paciente se movia a lo largo del eje Z. (1) Durante la decada siguiente, los tomografos monodetectores fueron progresivamente reemplazados por aparatos de multiples filas de detectores (TCMD). El resultado fue la adquisicion de imagenes con mayor resolucion temporal, menos ruido y mejor resolucion espacial en el eje Z. Este ultimo factor ha hecho posible la produccion de imagenes multiplanares de alta calidad que pueden tener relevancia clinica importante. (2) El reciente crecimiento de la disponibilidad de la angio-TCMD de 64 o hasta 320 detectores, no solamente han hecho posible reducir sustancialmente el tiempo de estudio, sino ademas se ha logrado un aumento en la resolucion espacial, comparable a la angiografia convencional. Por otro lado, a medida que fue aumentando el numero de detectores, se redujo la cantidad de material de contraste endovenoso administrado, lo cual permite la ejecucion inmediata de angiografia convencional, si es necesario acudir a procedimientos de intervencionismo para reparar la lesion vascular encontrada. Sin embargo, es importante enfatizar en el hecho de que, a pesar de todos los logros antes mencionados, la consecuencia ha sido un aumento sustancial en la cantidad de radiacion a que estos pacientes son sometidos durante tales estudios. El efecto carcinogenico potencial de TCMD debe de ser considerado como un tema crucial, especialmente en mujeres jovenes. En un estudio reciente en el cual se utilizo TCMD en el diagnostico de tromboembolismo pulmonar, se calculo que la radiacion minima al tejido mamario en una mujer de 60 kg fue de 20 mGy en cada mama. (3) Para ponerlo en perspectiva, eso equivale aproximadamente a 10-25 mamografias o a 100-400 radiografias de torax. Por eso es imprescindible que cada estudio sea protocolizado apropiadamente, de tal forma que haya un balance adecuado de la ecuacion riesgo/beneficio, para que la informacion adquirida sea adecuada y suficiente, dependiendo del cuadro clinico. Mientras que en los ultimos anos, se ha logrado mejorar la rapidez y la resolucion temporal y espacial, el enfasis actual de los distintos fabricantes de estos equipos se basa precisamente en la aplicacion de distintos metodos tecnologicos para reducir la radiacion total del paciente. (4) En este numero de la Revista, Cerda y col. revisan su experiencia con angio-TCMD en la patologia aortica. En este interesante articulo, sus autores utilizaron un equipo de 64 canales y realizaron reconstrucciones multiplanares y tridimensionales en una estacion de trabajo. Un aspecto muy importante, en mi opinion, es que en la seccion de metodos, los mismos describen la utilizacion de la tecnica del gatillado electrocardiografico para suprimir artefactos de movimiento en la raiz de la aorta. Este es un detalle tecnico de importancia, pues a pesar de que se acompana de un aumento en la radiacion al paciente, puede ser el elemento crucial para evitar falsos positivos en pacientes con sospecha de diseccion de aorta. Este es un ejemplo caracteristico de como los beneficios obtenidos rebasan el riesgo correspondiente. Los autores clasifican su casuistica en tres aplicaciones clinicas: dilatacion, sindromes aorticos agudos y patologia estenosante. Cada seccion comienza con una descripcion de la entidad en particular, haciendo hincapie en los puntos importantes para la identifi-

Planned pulmonary resection for metastatic pulmonary tumor with video-assisted thoracoscopic surgery using multidetector row angiography

For video-assisted thoracic surgery (VATS) on metastatic pulmonary tumors, wedge resection using an endo-stapler is the standard procedure in many institutions. However, this procedure can miss lesions or compromise surgical margins, particularly with small, deep lesions. The planned pulmonary resection in this study is a surgical method for pulmonary resection aimed at a previously assigned pulmonary area. We determine the pulmonary area for anatomical or nonanatomical resection before surgery on the basis of tumor location in relation to the anatomical distribution of pulmonary vessels. Multidetector row computed tomography (MDCT) angiography contributed to preoperative planning for 12 patients with single (n = 11) or dual (n = 1) pulmonary metastases (diameter <3 cm) in the same lobe. Planned surgical procedures were nonanatomical stapling resection (partial resection) (n = 6) or segmentectomy (n = 6). One patient required conversion to lobectomy from segmentectomy, but all patients underwent curative pulmonary resection. Preoperative planning of VATS pulmonary resection using MDCT angiography allows reliable pulmonary resection for metastatic tumors.

Diagnostic accuracy and efficacy of multidetector-row computed tomography angiography for arteriosclerosis obliterance and renal artery stenosis, and clinical significance of simultaneous acquisition from kidney to lower limb

Diagnostic accuracy and efficacy of multidetector-row computed tomography angiography for arteriosclerosis obliterance and renal artery stenosis, and clinical significance of simultaneous acquisition from kidney to lower limb

The value of multidetector-row CT angiography for pre-operative planning of breast reconstruction with deep inferior epigastric arterial perforator flaps

The value of multidetector-row CT angiography for pre-operative planning of breast reconstruction with deep inferior epigastric arterial perforator flaps

64-Slice multidetector row CT angiography of the abdomen: comparison of low versus high concentration iodinated contrast media in a porcine model

In this study we aimed to assess the image quality and degree of vascular enhancement using low-concentration contrast media (LCCM) (300 mg I ml(-1)) and high-concentration contrast media (HCCM) (370 mg I ml(-1)) on 64-slice multidetector row CT (MDCT) abdominal CT angiography (CTA). In addition, we aimed to study the feasibility of using HCCM with a reduced total iodine dose. CTA of the abdomen on a 64-slice MDCT was performed on 15 anaesthetised pigs. Study pigs were divided into three groups of five each based on the iodine concentration and dose received: Group A (LCCM; 300 mg I ml(-1)), Group B (HCCM; 370 mg I ml(-1)) and Group C HCCM with 20% less iodine dose. The total iodine injected was kept constant (600 mg kg(-1)) in Groups A and B. Qualitative and quantitative analyses were performed to study and compare each group for image quality, visibility of the branch order of the superior mesenteric artery (SMA), artefacts, degree of enhancement in the aorta and main stem arteries and uniformity of enhancement in the aorta. Groups were compared using the analysis of variance test. The image quality of 64-slice MDCT angiography was excellent with a mean score of 4.63 and confident visualisation of the third to fifth order branches of the SMA in all groups. Group B demonstrated superior vascular enhancement, as compared with Groups A and C (p≤0.05). Uniform aortic enhancement was achieved with the use of LCCM and HCCM with 20% less iodine dose. 64-slice MDCT angiography of the abdomen was of excellent quality. HCCM improves contrast enhancement and overall CTA image quality and allows the iodine dose to be reduced.

Current Contrast Media Delivery Strategies for Cardiac and Pulmonary Multidetector-row Computed Tomography Angiography

Recent advances in multidetector-row computed tomography (MDCT) have led to substantial improvements in coverage area, acquisition speed, and temporal/spatial resolution, which have strengthened the performance of thoracic and cardiac MDCT angiography but have also imposed new challenges for optimization of contrast medium enhancement and scan acquisition strategies. Understanding contrast media dynamics is fundamental for the design of scan acquisition and injection protocols. This article examines the fundamentals of the physiological and contrast delivery factors that determine the quality of contrast enhancement, emphasizing the modifications required in contrast delivery protocols for optimizing cardiothoracic MDCT angiography with modern-era MDCT scanners.

The Utility of Multidetector-Row Computed Tomography Angiography for Evaluating Perforators of Fibular Osteocutaneous Flaps

Multidetector-row computed tomography angiography (MDCTA) can be used to visualize small vessels and has been used to search for perforators in deep inferior epigastric artery perforator flaps and anterolateral thigh flaps. Fibula osteocutaneous flaps are often used for mandibular reconstruction, but questions remain about the reliability of these flaps and the variety of their perforators. Eight patients who were candidates for mandibular or pedal reconstruction with a fibula osteocutaneous flap were prospectively evaluated with MDCTA and Doppler sonography. We evaluated the number, position, and course of perforators with MDCTA. The perforators were classified, and intraoperative findings were compared with those of Doppler sonography and MDCTA. MDCTA accurately identified the perforators and showed a satisfactory concordance with intraoperative findings. The high spatial resolution of MDCTA allows the perforators' origin, course, and type to be precisely described. Eighteen vessels were identified with MDCTA, and on average, 2.3 vessels were identified in the leg of each patient. The rate of concordance with operative findings was 87.5% for MDCTA. With MDCTA, flap perforators can be accurately evaluated before surgery in a manner not possible with traditional angiography or Doppler sonography. Reliable perforators can be chosen, and detailed operative plans can be made.

Extent of Thoracic Aortic Atheroma Burden and Long-Term Mortality After Cardiothoracic Surgery: A Computed Tomography Study

We hypothesized that the extent of aortic atheroma of the entire thoracic aorta, determined by pre-operative multidetector-row computed tomographic angiography (MDCTA), is associated with long-term mortality following nonaortic cardiothoracic surgery. In patients evaluated for cardiothoracic surgery, presence of severe aortic atheroma is associated with adverse short- and long-term post-operative outcome. However, the relationship between aortic plaque burden and mortality remains unknown. We reviewed clinical and imaging data from all patients who underwent electrocardiographic-gated contrast-enhanced MDCTA prior to coronary bypass or valvular heart surgery at our institution between 2002 and 2008. MDCTA studies were analyzed for thickness and circumferential extent of aortic atheroma in 5 segments of the thoracic aorta. A semiquantitative total plaque-burden score (TPBS) was calculated by assigning a score of 1 to 3 to plaque thickness and to circumferential plaque extent. When combined, this resulted in a score of 0 to 6 for each of the 5 segments and, hence, an overall score from 0 to 30. The primary end point was all-cause mortality during long-term follow-up. A total of 862 patients (71% men, 67.8 years) were included and followed over a mean period of 25 ± 16 months. The mean TPBS was 8.6 (SD: ±6.0). The TPBS was a statistically significant predictor of mortality (p < 0.0001) while controlling for baseline demographics, cardiovascular risk factors, and type of surgery including reoperative status. The estimated hazard ratio for TPBS was 1.08 (95% confidence interval: 1.045 to 1.12). Other independent predictors of mortality were glomerular filtration rate (p = 0.015), type of surgery (p = 0.007), and peripheral artery disease (p = 0.03). Extent of thoracic aortic atheroma burden is independently associated with increased long-term mortality in patients following cardiothoracic surgery. Although our data do not provide definitive evidence, they suggest a relationship to the systemic atherosclerotic disease process and, therefore, have important implications for secondary prevention in post-operative rehabilitation programs.

Assessment of modified Blalock–Taussig shunt in children with congenital heart disease using multidetector-row computed tomography

The purpose of this study was to assess the feasibility of multidetector-row computed tomography (MDCT) for the evaluation of modified Blalock-Taussig (B-T) shunt in children with congenital heart disease associated with reduced pulmonary blood flow. A total of 25 consecutive patients (mean age, 2.6 ± 3.6 years; range, 2 months-16 years) underwent MDCT angiography of the thorax with a 16-detector row scanner prior to cardiac catheterization. A total of 39 shunts (right, 22; left, 17) were included in the study. Conventional angiographic findings were used as the gold standard for the detection of B-T shunts. Shunt diameter was measured quantitatively and independently at four sites (the subclavian artery site, the pulmonary artery site, the widest site, and the stenotic site) on MDCT and on conventional invasive angiography. All B-T shunts were depicted on multiplanar reconstruction (MPR), maximum intensity projection (MIP), curved planar reconstruction (CPR), and three-dimensional volume-rendered (VR) images, enabling evaluation in all patients except for one with occluded shunt. There were excellent correlations between MDCT- and conventional angiography-based measurements of shunt diameter at the subclavian artery site, pulmonary artery site, and the widest site (R² = 0.46, 0.74 and 0.64, respectively; p < 0.0001 for each), although systematic overestimation was observed for MDCT (mean percentage of overestimation, 23.1 ± 32.4%). Stenotic site diameter and degree of stenosis showed a mild correlation (R² = 010 and 0.25, respectively; p < 0.01 for each). This study demonstrates that MDCT is a promising tool for the detection of lesions in B-T shunts.