Multidetector-row Computed Tomography Data Research Articles

A Three-Dimensional Anterior and Middle Cranial Fossa Model for Skull Base Surgical Training with Two Layers of the Colored Dura Mater

Adequate epidural procedures and anatomical knowledge are essential for the technical success of skull base surgery. We evaluated the usefulness of our three-dimensional (3D) model of the anterior and middle cranial fossa as a learning tool in improving knowledge of anatomy and surgical approaches, including skull base drilling and dura matter peeling techniques. Using a 3D printer, a bone model of the anterior and middle cranial fossa was created based on multi-detector row computed tomography data, incorporating artificial cranial nerves, blood vessels, and dura mater. The artificial dura mater was painted using different colors, with 2 pieces glued together to allow for the simulation of peeling the temporal dura propria from the lateral wall of the cavernous sinus. Two experts in skull base surgery and 1 trainee surgeon operated on this model and 12 expert skull base surgeons watched the operation video to evaluate this model subtlety on a scale of 1 to5. A total of 15 neurosurgeons, 14 of whom were skull base surgery expert, evaluated, scoring 4 or higher on most of the items. The experience of dural dissection and 3D positioning of important structures, including cranial nerves and blood vessels, was similar to that in actual surgery. This model was designed to facilitate teaching anatomical knowledge and essential epidural procedure-related skills. It was shown to be useful for teaching essential elements of skull-base surgery.

Matching the perforating branch of the internal thoracic artery and the deep inferior epigastric artery for breast reconstruction using multi-detector row computed tomography.

Matching the diameter of the deep inferior epigastric artery (DIEA) and perforating branch (PB) of the internal thoracic artery (ITA) is important for arterial anastomosis during breast reconstruction using the DIEA flap. An anatomic investigation of these arteries was performed using multidetector row computed tomography (MDCT). Contrast-enhanced MDCT data of 50 women (aged 18-90years) covering the neck to the groin were analyzed. The diameter of the PBs of the ITA at their origins from the first to the sixth intercostal space and of the DIEA 20mm from the bifurcation of the external iliac artery were measured. The mean diameters of the right and left DIEAs were 1.53 ± 0.263mm and 1.53 ± 0.306mm, respectively. The diameter of the PBs in the second and third intercoastal spaces was the same as the diameter of the DIEA, bilaterally. It is suggested that anastomosis of the DIEA with PBs of the ITA in the second and third intercoastal spaces is optimal for DIEA flap grafting. Our results could contribute to making vascular anastomosis easier, thereby reducing the burden on both surgeons and patients.

Impact of baseline feature tracking multi-detector row computed tomography-derived left ventricular global longitudinal strain on left ventricular functional recovery in TAVI patients

Abstract Background Advances in left ventricular (LV) analysis with dynamic multi-detector row computed tomography (MDCT) permit measurement of LV global longitudinal strain (GLS) and have shown their impact on risk stratification of patients with aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). Purpose To evaluate the influence of baseline feature tracking (FT) MDCT- derived LV GLS on LV functional recovery in severe AS patients undergoing TAVI. Methods A total of 194 patients with severe AS (50% male, 80±7 years) with dynamic MDCT data allowing LV GLS measurement with a novel FT algorithm and having complete echocardiography evaluation at baseline, at 3–6 months and at 1 year follow-up were evaluated. FT MDCT-derived LV GLS was measured at baseline and the study population was divided according to a cut-off value of MDCT LV GLS −14% (≤−14% [more preserved LV systolic function] vs. >−14% [more impaired LV systolic function]). Results Transthoracic echocardiography (TTE)-derived Left ventricular ejection fraction (LVEF) increased over time in both groups: in patients with preserved and reduced MDCT LV GLS, and reached a higher value in patients with preserved MDCT LV GLS (52±7% at baseline, 55±7% at 3–6 months, 58±7% at 1 year follow-up vs. 43±10% at baseline, 49±10% at 3–6 months, 53±11% at 1 year follow-up; p=0.016) (Figure 1). TTE-derived LV GLS also showed greater improvement for patients with preserved MDCT LV GLS (−17±3% at baseline, −18±3% at 3–6 months, −20±3% at 1 year follow-up vs. −12±3% at baseline, −15±3% at 3–6 months, −16±3% at 1 year follow-up; p=0.027) (Figure 1). Conclusions In severe AS patients treated with TAVI, LV function improves significantly at 3–6 and at 12 months' follow-up and shows superior recovery in patients with more preserved baseline MDCT LV GLS, suggesting that MDCT-derived LV GLS has an important impact on LV functional recovery after TAVI. Funding Acknowledgement Type of funding source: None

Prognostic Influence of Feature Tracking Multidetector Row Computed Tomography-Derived Left Ventricular Global Longitudinal Strain in Patients with Aortic Stenosis Treated With Transcatheter Aortic Valve Implantation

Computed tomography plays a central role in the evaluation of patients with severe aortic stenosis who underwent transcatheter aortic valve implantation (TAVI). Advances in left ventricular (LV) analysis with multidetector row computed tomography (MDCT) permit measurement of LV global longitudinal strain (GLS). The present study aimed at evaluating the association between feature tracking (FT) MDCT derived LV GLS and all-cause mortality in patients treated with TAVI. A total of 214 patients with severe aortic stenosis (51% male, 80 ± 7 years) who underwent TAVI and with dynamic MDCT data allowing LV GLS measurement with novel FT algorithm were included. LV GLS was measured at baseline and were divided according to a previously published cut-off value of LV GLS associated with all-cause mortality (≤-14% [more preserved LV systolic function] vs >-14% [more impaired LV systolic function]). Patients were followed for the occurrence of all-cause mortality. Mean FT MDCT-derived LV GLS was -12.5 ± 4%. During a median follow-up of 45 months (interquartile range: 29 to 62 months), 67 (31%) patients died. The cumulative rate of all-cause mortality for the patients with FT MDCT-derived LV GLS ≤-14% was 15% versus28% for the patients with FT MDCT-derived LV GLS >-14%, Log rank p = 0.001). FT MDCT-derived LV GLS was independently associated with all-cause mortality (hazard ratio: 0.851; 95% confidence interval: 0.772 to 0.937; p = 0.001). In conclusion, impaired FT MDCT-derived LV GLS is independently associated with all-cause mortality in patients treated with TAVI. Besides aortic valve area and calcification, FT MDCT-derived LV GLS is an important prognostic marker.

Feature tracking computed tomography-derived left ventricular global longitudinal strain in patients with aortic stenosis: a comparative analysis with echocardiographic measurements

BackgroundLeft ventricular (LV) systolic function is a prognostic factor in patients with severe aortic stenosis (AS). Multi-detector row computed tomography (MDCT) data are key in the evaluation of patients undergoing transcatheter aortic valve implantation (TAVI) and when acquired retrospectively, LV systolic function can be assessed. Novel software permits assessment of LV global longitudinal strain (GLS) from MDCT data. ObjectivesThe present study investigated the feasibility of feature tracking MDCT-derived LV GLS and its agreement with echocardiographic LV GLS in patients treated with TAVI. MethodsLV GLS was measured on transthoracic echocardiography using speckle tracking analysis and on dynamic MDCT using feature tracking technology. Agreement between the measurements of two different modalities was assessed using Bland-Altman analysis. ResultsA total of 214 patients (51% male, mean age: 80 ± 7 years) were analysed. Mean LV GLS on echocardiography was −13.91 ± 4.32%, whereas mean feature tracking MDCT-derived GLS was −12.46 ± 3.97%. Correlation of measurements between feature tracking MDCT-derived LV GLS and echocardiographic LV GLS demonstrated a large effect size (r = 0.791, p < 0.001). On Bland-Altman analysis, feature tracking MDCT-derived strain analysis underestimated LV GLS compared to echocardiography with a mean difference of 1.44% (95% limits of agreement −3.85% - 6.73%). ConclusionsAssessment of LV GLS on dynamic feature tracking MDCT data is feasible in TAVI patients. Compared to speckle tracking echocardiography, feature tracking MDCT underestimates the value of LV GLS.

P3377MDCT-derived left ventricular global longitudinal strain and left ventricular ejection fraction in patients with aortic stenosis: a comparative analysis with echocardiographic measurements

Abstract Introduction Known predictors of poor outcome in aortic valve stenosis patients include older age, significant valvular calcification, rapid hemodynamic progression and impaired left ventricular (LV) systolic function. LV global longitudinal strain (GLS) quantifies myocardial deformation and LV function and is associated with prognosis in patients with severe aortic stenosis (AS). Multi-detector row computed tomography (MDCT) data are key in the evaluation of patients undergoing transcatheter aortic valve implantation (TAVI) and when acquired throughout the entire cardiac cycle, LV systolic function can be assessed. Novel software can assess LV GLS from MDCT-data. Purpose The present study aimed at assessing the feasibility of determining novel MDCT-derived LV GLS as well as MDCT-derived LV ejection fraction (EF) and their agreement with echocardiographic LV GLS and LVEF in patients treated with TAVI. Methods LVEF and LV GLS were measured on echocardiography and dynamic MDCT using novel CT-software. Agreement between the measurements of two different modalities was assessed using Bland-Altman analysis. Results A total 214 patients (51% male, mean age: 80±7 years) were analysed retrospectively. Mean value of LV GLS on echocardiography was −14±4% whereas mean MDCT-derived GLS was −12.5±4%. Mean value of LVEF on echocardiography was 47±10% and mean MDCT-derived LVEF was 39±11%. On Bland-Altman analysis, MDCT-derived strain analysis underestimated LV GLS compared to echocardiography with a mean difference of 1.44% (95% limits of agreement −3.8 to 6.7%). LVEF was also underestimated on CT with a mean difference of 7.68% (95% limits of agreement −11.5% to −26%). Correlation of measurements between MDCT-derived LV GLS and echocardiographic LV GLS was significant (r=0.791, p&lt;0.001), as well as the correlation between MDCT-derived LVEF and echocardiographic LVEF (r=0.590, p&lt;0.001) (Figure). Conclusions Assessment of LV GLS and LVEF on dynamic MDCT data provides similar values to those obtained with echocardiography and could be used in the risk-stratification of severe AS patients undergoing TAVI.

Computed tomography predictors of mortality, stroke and conduction disturbances in women undergoing TAVR: A sub-analysis of the WIN-TAVI registry

BackgroundAortic valve calcification patterns were associated with short- and long-term outcomes in previous small observational datasets of patients undergoing transcatheter aortic valve implantation (TAVI). The specific impact of multi detector-row computed tomography (MDCT) findings on outcomes in women has not been reported. We sought to describe the associations between MDCT characteristics and clinical outcomes in a registry of 547 women undergoing TAVI. MethodsWIN-TAVI is the first all-female registry to study the safety and effectiveness of TAVI in women (n = 1019). Thirteen sites participated in the MDCT sub-study and contributed pre-TAVI MDCT studies in 547 consecutive subjects. All MDCT data were analyzed in an independent core lab blinded to clinical outcomes. Key measurements included number of valve leaflets, aortic annulus area and perimeter, left and right coronary artery height, aortic cusp calcium volume, commissural calcification and left ventricular outflow tract (LVOT) calcification. Calcium volume of the aortic valvular complex was quantified using a threshold relative to patient-specific contrast attenuation in the arterial blood pool. We examined univariate and multivariate associations between ECG-gated contrast MDCT characteristics and 1-year mortality or stroke, new pacemaker implantation and new onset atrial fibrillation (AF). ResultsThe CT sub-study sample had a mean age of 82.8 ± 6.3 years, mean logistic EuroSCORE of 17.8 ± 11.3%, and mean STS score of 8.2 ± 7.4%. Transfemoral access was used in 89.6% of patients. After multivariate adjustment, moderate or severe LVOT calcification was an independent predictor of 1-year mortality or stroke (HR = 1.91; 95% CI: 1.11–3.30; p = 0.02). Calcium volume in the right coronary cusp was an independent predictor of new pacemaker (HR = 1.18 per 100 m3 increment; p = 0.04), whereas calcium volume of the non-coronary cusp had a protective effect (HR = 0.78 per 100 mm3 increment; p = 0.004). Severe calcification of the non-coronary/right-coronary commissure was an independent predictor of new AF (HR = 5.1; p = 0.008). ConclusionComputed tomography provides important prognostic information in women undergoing TAVI. Moderate or severe LVOT calcification is associated to an almost two-fold increased risk of mortality or stroke at one year. Different calcification patterns of the aortic valve may predict diverse rhythm abnormalities.

MDCT and MRI for the diagnosis of complex fractures of the tibial plateau: A case control study

The aim of this study was to evaluate the clinical value of multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI) in the diagnosis and treatment of complex fractures of the tibial plateau. A total of 71 patients with complex fractures of the tibial plateau (estimated Schatzker classifications III, V and VI) were included in this study. The X-ray, MDCT and MRI data obtained from the patients were analyzed. MDCT was the most sensitive method in the diagnosis of tibial articular surface collapse, cruciate ligament tibial avulsion fracture, degree of fracture comminution and degree of fracture displacement (P<0.01). MRI was the most sensitive method in the diagnosis of injuries of the cruciate and collateral ligaments, menisci and cartilage peeling of the articular surfaces (P<0.01). MDCT and MRI were demonstrated to be more sensitive than X-rays for the diagnosis of insidious damage around the knee.

Multidetector-row computed tomography for evaluating the branching angle of the celiac artery: a descriptive study

BackgroundWe performed this study in order to investigate the shape of the origin of the celiac artery in maximum intensity projection (MIP) using routine 64 multidetector-row computed tomography (MDCT) data in order to plan for the implantation of an intra-arterial hepatic port system.MethodsA total of 1,104 patients with hepatocellular carcinoma were assessed with MDCT. In the definition of the branching angle, the anterior side of the abdominal aorta was considered the baseline, and the cranial and caudal sides were designated as 0 and 180 degrees, respectively. The angles between 0 and 90 degrees and between 90 and 180 degrees from the cranial side were considered upward and downward, respectively, and the branching angle of the celiac artery was classified every 30 degrees. The subclavian arterial route was used for the implantation of an intra-arterial hepatic port system in patients with branching angles of 150 degrees or more (sharp downward).ResultsThe median branching angle was (median ± standard deviation) 135 ± 23 (range, 51–174) degrees. The branching was upward in 77 patients (7%) and downward in 1,027 patients (93%). The branching was downward with an angle of 120 to150 degrees in most patients (n = 613). The branching was sharply downward with an angle of 150 degrees or more in 177 patients (16%). A total of 10 patients were referred for interventional placement of an intra-arterial hepatic port system. The subclavian arterial route was used for implantation of an intra-arterial hepatic port system in 2 patients with sharp downward branching.ConclusionsThe branching angle of the celiac artery can be easily determined by the preparation of MIP images from routine MDCT data. MIP may provide useful information for the selection of the catheter insertion route in order to avoid a sharp branching angle of the celiac artery.

Morphometric analysis of the lumbar intervertebral foramen in patients with degenerative lumbar scoliosis by multidetector-row computed tomography

How the lumbar neural foramina are affected by segmental deformities in patients in whom degenerative lumbar scoliosis (DLS) is unknown. Here, we used multidetector-row computed tomography (MDCT) to measure the morphology of the foramina in three dimensions, which allowed us to elucidate the relationships between foraminal morphology and segmental deformities in DLS. In 77 DLS patients (mean age, 69.4) and 19 controls (mean age, 69), the foraminal height (FH), foraminal width (FW), posterior disc height (PDH), interval between the pedicle and superior articular process (P-SAP), and cross-sectional foraminal area (FA) were measured on reconstructed MDCT data, using image-editing software, at the entrance, minimum-area point, and exit of each foramen. The parameters of segmental deformity included the intervertebral wedging angle and anteroposterior and lateral translation rate, measured on radiographs, and the vertebral rotation angle, measured using reconstructed MDCT images. The FH, PDH, P-SAP, and FA were smaller at lower lumbar levels and on the concave side of intervertebral wedging (p < 0.05). In the DLS patients, the FH, P-SAP, and FA were significantly smaller than for the control group at all three foraminal locations and every lumbar level (p < 0.05). Intervertebral wedging strongly decreased the FA of the concave side (p < 0.05). Anteroposterior translation caused the greatest reduction in P-SAP (p < 0.05). Vertebral rotation decreased the P-SAP and FA at the minimum-area point on the same side as the rotation (p < 0.05). The new analysis method proposed here is useful for understanding the pathomechanisms of foraminal stenosis in DLS patients.

Three-dimensional computed tomography analysis of neoglottis after supracricoid laryngectomy with cricohyoidoepiglottopexy

Supracricoid laryngectomy with cricohyoidoepiglottopexy is an organ-preserving procedure used to treat laryngeal cancer. However, the post-operative neoglottis tends to be variable in form and difficult to predict. We retrospectively analysed three-dimensional images reconstructed from multidetector-row computed tomography data for 21 patients, assessing arytenoid motion and minimum neoglottic gap cross-sectional area. While mean transverse and coronal motion was similar for bilateral and unilateral arytenoids, movement along the sagittal axis was greater for unilateral than bilateral arytenoids. The neoglottic gap during respiration was wider in patients with bilateral arytenoids, but both groups had a similar neoglottic gap during phonation. Anterior shifting of the unilateral arytenoid plays an important role in compensating for the inability to achieve neoglottic closure. These two results demonstrate that the unilateral arytenoid alone is capable of achieving sufficient neoglottic narrowing to compensate for the resected arytenoid. Three-dimensional analysis was useful to evaluate the physiological status of the neoglottis after supracricoid laryngectomy with cricohyoidoepiglottopexy.

Cardiac surgery for annuloaortic ectasia and mitral regurgitation in an adult patient with dextrocardia

We report a surgical case of dextrocardia complicated with annuloaortic ectasia (AAE) and mitral regurgitation, which induced congestive heart failure. Preoperative electrocardiography-gated multidetector-row computed tomography (MDCT) showed the following complex cardiovascular abnormalities without motion artifacts: dextrocardia, situs inversus, polysplenia, AAE, absence of the inferior vena cava, azygos vein continuation, drainage of the hepatic vein into the right atrium, and bilateral superior venae cavae. On the basis of the MDCT data, we established a cardiopulmonary bypass; and a modified Bentall procedure (Piehler method) and mitral valve replacement were performed without complications.

Comparison of global left ventricular function using 20 phases with 10-phase reconstructions in multidetector-row computed tomography

To compare the measurement of global left-ventricular (LV) function parameters of 64-slice multidetector-row computed tomography (MDCT) between 20- and 10-reconstruction phases. Fifty five patients with suspected or known coronary artery disease underwent 64-slice MDCT. LV end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) were measured from MDCT data sets using threshold-based volume segmentation and reconstruction at every 5% (20 phases) and 10% (10 phases) step through the R-R interval. These global functional parameters were compared to those obtained via two-dimensional transthoracic echocardiography (2D-TTE), considering the reference standard. The required time for CT data analysis was checked. Agreement for parameters of LV global function was determined using Pearson's correlation coefficient (r) and Bland-Altman analysis. LV volumes (EDV(-5%) 87.5 ± 17.1 ml, EDV(-10%) 87.7 ± 16.3 ml; ESV(-5%) 32.4 ± 10.6 ml, ESV(-10%) 31.9 ± 9.9 ml; SV(-5%) 55.1 ± 10.5 ml, SV(-10%) 55.8 ± 9.9 ml; mean ± SD) and EF (EF(-5%) 63.4 ± 6.2%, EF(-10%) 63.9 ± 5.8%) did not differ significantly between the 20- and 10 phase reconstructions, and evidenced good to excellent correlation (r = 0.786-0.896, all P < 0.001) with the 2D-TTE results. The mean required time for CT data analysis in the 20- and 10 phase reconstructions were 15.5 ± 4.0 and 7.3 ± 2.5 min. Within MDCT, using 10-phase image reconstruction is sufficient to evaluate LV volumes and EF, and is also more time-effective than 20-phase reconstruction.

Identification of Ryu's Segmentation of the Liver Using MDCT Analysis

Couinaud's segmentation is widely used for clinical segmentation of the liver. Recently, a new method of liver segmentation was described by Ryu. In this method, the right posterior sector in Couinaud's segmentation is regarded as 1 segment, and the right anterior sector is subdivided into the antero-ventral segment (AVS) and the antero-dorsal segment (ADS), which are demarcated by the anterior fissure vein (AFV). We used data from multi-detector row computed tomography (MDCT) to identify the portal and hepatic veins that are used as anatomical landmarks in both Couinaud's segmentation and Ryu's segmentation. We analyzed data from 100 patients who had no space occupying lesions of the liver and had undergone abdominal CT examination from June through September 2008. MDCT was used to obtain contrast-enhanced helical scans of the whole liver during the portal venous phase. Using thin-slice data, we attempted to identify the portal and hepatic veins, in particular the anterior fissure vein (AFV), the antero-ventral portal vein (AVPV), and the antero-dorsal portal vein (ADPV), all of which are used in Ryu's segmentation. In all cases, we were able to identify the hepatic segments of Couinaud's segmentation. However, in several cases, we were unable to identify the segments used in Ryu's segmentation. The AFV flowed into the intermediate hepatic vein (IHV) in 88% of cases and into the right hepatic vein (RHV) in 12%. Among the former, the AFV flowed into the proximal IHV in 53% of cases. Although the AFV could be identified in these cases, it was difficult to determine the border between the AVS and the ADS. Our findings indicate that the use of MDCT data to identify hepatic anatomy was more difficult in Ryu's segmentation than in Couinaud's segmentation, because the AFV could not be easily identified in the former. Indeed, even when the AFV could be identified, its use as a landmark was often questionable.

Investigation of Hyperpolarized 3He Magnetic Resonance Imaging Utility in Examining Human Airway Diameter Behavior in Asthma Through Comparison with High-Resolution Computed Tomography

Application of a previously developed model-based algorithm on hyperpolarized (HP) (3)He magnetic resonance (MR) dynamic projection images of phantoms was extended to investigate the utility of HP (3)He MR imaging (MRI) in quantifying airway caliber changes associated with asthma. Airways of seven volunteers were imaged and measured using HP (3)He MRI and multidetector-row computed tomography (MDCT) before and after a methacholine (MCh) challenge. MDCT data were obtained at functional residual capacity and 1 L above functional residual capacity. Comparison of the resultant data showed that HP (3)He MRI did not match MDCT in measuring the ratios of airway calibers before and after the MCh challenge in 37% to 43% of the airways from the first six generations at the two lung volumes tested. However, MDCT did yield the observation that 49% to 69% of these airways displayed bronchodilation following MCh challenge. The current implementation of HP (3)He MRI did not match the MCh-induced postchallenge-to-prechallenge airway caliber ratios as measured with MDCT. Elevated parenchymal tethering due to bronchoconstriction-induced hyperinflation was proposed as a possible explanation for this airway dilation.

Assessing Culprit Lesions and Active Complex Lesions in Patients With Early Acute Myocardial Infarction by Multidetector Computed Tomography

Accurate, non-invasive characterization of culprit lesions in patients after acute myocardial infarction (AMI) remains challenging. In this prospective study, multidetector row computed tomography (MDCT) is used to assess culprit and active complex lesions in patients early after AMI. We enrolled 103 patients with first non ST-elevation AMI who underwent 64-slices MDCT and conventional coronary angiography (CCAG). The definition of culprit lesion, stable non-culprit lesions and non-culprit active complex lesions was based on the findings of CCAG. The lesions were analyzed with MDCT data. In culprit lesions (n=103), luminal artery stenosis, remodeling index, plaque area and burden were significantly higher than non-culprit lesions (n=129). Multivariate discriminant analysis showed that MDCT density could discriminate culprit from non-culprit lesions. Receiver-operator characteristic curve analysis identified the optimal cutoff value of lesion density for discrimination between culprit and non-culprit lesion as 49.6 Hounsfield units (HU); this value was associated with a sensitivity, specificity and accuracy of 88.4%, 87.4%, and 87.9%, respectively. The MDCT in the stable non-culprit lesions (81.8+/-15.5 HU) was significantly higher than that in culprit lesions or non-culprit active complex lesions (33.2+/-13.8 and 48.3+/-15.7 HU, p<0.001). MDCT can predict culprit lesions in patients early after AMI, and identify multiple complex lesions.

Postprocessing technique with MDCT data improves the accuracy of the detection of lung nodules

The aim of this study was to determine whether postprocessing techniques could improve the accuracy of detecting lung nodules. A total of 154 segmented lung volumes of multidetector-row computed tomography (MDCT) data were the subject of the study. Lung nodules were present in 88 volumes and absent in 66 volumes. We prepared four groups: (1) 7- or 10-mm thick-section axial images; (2) 1-mm thin-section axial images; (3) sliding slab maximum intensity projection (MIP) images with a slab thickness of 15 mm; and (4) sliding slab volume rendering (VR) images with a slab thickness of 15 mm. Sixteen physicians reviewed each group in interactive cine mode. The observers' performance in the detection of lung nodule was evaluated by receiver operating characteristic (ROC) analysis. The observers' performance of the MIP and VR groups was significantly better than in other two groups. There was no significant difference statistically between the thin and thick groups. The detectability of lung nodules is improved with the use of sliding slab MIP and VR using thin-section image data. Thin-section volume data are essential for improving diagnostic accuracy, but observation of thin-section images without utilization of image-processing techniques dose not improve diagnostic accuracy.

Multidetector row computed tomography can identify and characterize the occlusive culprit lesions in patients early (within 24 hours) after acute myocardial infarction

The reliable noninvasive assessment of occluded disrupted plaques and thromboses in culprit vessels could constitute an important step forward in risk stratification of patients early after acute myocardial infarction (AMI). However, noninvasive identification of patency of culprit vessels remains a challenging issue. This prospective study was designed to identify the occluded culprit vessels by multidetector row computed tomography (MDCT) and to compare the stenotic and occlusive culprit lesions by MDCT in patients early (within 24 hours) after AMI. We enrolled 62 patients with first Q-wave AMI (54 males). Multidetector row computed tomography was performed 16.5 +/- 7.1 hours after the onset of chest pain without any complication. Coronary angiography was done within 6 hours after MDCT. Patients were divided into 2 groups according to angiographic findings: stenotic group (35 patients) and occluded group (27 patients). The following MDCT data were collected: luminal artery stenosis, remodeling index, plaque burden, and lesion attenuation. Compared to coronary angiography, MDCT detected occluded culprit vessels with sensitivity, specificity, negative predict value, and positive predict value of 92.6%, 88.6%, 93.9%, and 86.2%, respectively. Compared with the stenotic group, culprit lesions in the occlusive group had significantly longer length (18.9 +/- 9.7 vs 11.9 +/- 6.2 mm; P = .024) and higher MDCT lesion attenuation (38.8 +/- 15.6 vs 29.2 +/- 12.9 Hounsfield unit; P = .008). Multidetector row computed tomography attenuation was negatively correlated with thrombolysis in myocardial infarction flow (Spearman rho = -0.46; P < .001). Multidetector row computed tomography could accurately and safely identify occluded culprit lesions in patients early after AMI, providing important information to aid in risk stratification.

Automated vs. manual assessment of left ventricular function in cardiac multidetector row computed tomography: comparison with magnetic resonance imaging

We compared semiautomatic contour detection and manual contour tracing in cardiac multidetector row computed tomography (MDCT) with magnetic resonance imaging (MRI) for calculation of left-ventricular (LV) volumes. The study included 30 patients who underwent contrast-enhanced cardiac MDCT and cardiac cine-MRI. Were calculated 8 mm short-axis slices from MDCT data using three-dimensional multiphase image reconstruction. LV volumes including peak ejection rate and peak filling rate were calculated from manually and semiautomatically determined contours. Results were compared to those from cine-MRI with manually drawn contours as the standard of reference. We found good agreement for the LV volumes, with an ejection fraction of 47.1+/-9.4% for manually drawn contours, 47.9+/-9.9% for semiautomatically detected contours on MDCT, and 48.0+/-10.2% for MRI. Except for peak-filling rate analysis of variance revealed no difference between any of these techniques. Bland-Altman plots and Lin's concordance correlation coefficient showed best agreement between MRI and manual contour tracing in MDCT. Calculation of LV volumes using either semiautomatic or manual contour tracing in cardiac MDCT is therefore feasible when compared to MRI. Automated contour detection needs to be improved to equal manual contour tracing.

Small-Bowel Obstruction: Coronal Reformations from Isotropic Voxels at 16-Section Multi–Detector Row CT

To retrospectively assess the added value of coronal reformations of the abdomen and pelvis from isotropic voxels by using 16-section multi-detector row computed tomography (CT) for the diagnosis of small-bowel obstruction (SBO). This HIPAA-compliant study was approved by the institutional review board of this medical center with a waiver of informed consent. One hundred consecutive patients (40 men and 60 women; mean age, 55 years) suspected of having SBO and abdominal pain underwent 16-section multi-detector row CT with coronal reformations. Twenty-nine patients had a final diagnosis of SBO, and 71 patients did not. Three independent readers blinded to the diagnosis interpreted the CT scout scan, then transverse scans alone, and then transverse plus coronal scans for the presence of SBO and abnormal wall enhancement. Confidence was scored with a 1-5 scale (1 = absent, 5 = present). Mean sensitivity and specificity of CT scout alone, transverse CT alone, and transverse plus coronal CT for the diagnosis of SBO were 88% and 86%, 87% and 87%, and 87% and 90%, respectively (not significant). In patients without SBO, transverse plus coronal CT enhanced confidence in the exclusion of SBO (P = .01). In patients with SBO, transverse plus coronal CT enhanced confidence in the diagnosis of SBO and identification of abnormal wall enhancement (P = .01). Transverse 16-section multi-detector row CT data sets are an excellent test for the diagnosis of SBO, while the addition of coronal reformations obtained from these isotropic data sets adds confidence to the diagnosis and exclusion of SBO.