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Borut Marincek

Publications and source records attributed to Borut Marincek.

At least 19 recordsLinked to original sources
PubMed2007

Coronary artery stent geometry and in-stent contrast attenuation with 64-slice computed tomography.

We aimed at assessing stent geometry and in-stent contrast attenuation with 64-slice CT in patients with various coronary stents. Twenty-nine patients (mean age 60 +/- 11 years; 24 men) with 50 stents underwent CT within 2 weeks after stent placement. Mean in-stent luminal diameter and reference vessel diameter proximal and distal to the stent were assessed with CT, and compared to quantitative coronary angiography (QCA). Stent length was also compared to the manufacturer's values. Images were reconstructed using a medium-smooth (B30f) and sharp (B46f) kernel. All 50 stents could be visualized with CT. Mean in-stent luminal diameter was systematically underestimated with CT compared to QCA (1.60 +/- 0.39 mm versus 2.49 +/- 0.45 mm; P < 0.0001), resulting in a modest correlation of QCA versus CT (r = 0.49; P < 0.0001). Stent length as given by the manufacturer was 18.2 +/- 6.2 mm, correlating well with CT (18.5 +/- 5.7 mm; r = 0.95; P < 0.0001) and QCA (17.4 +/- 5.6 mm; r = 0.87; P < 0.0001). Proximal and distal reference vessel diameters were similar with CT and QCA (P = 0.06 and P = 0.03). B46f kernel images showed higher image noise (P < 0.05) and lower in-stent CT attenuation values (P < 0.001) than images reconstructed with the B30f kernel. 64-slice CT allows measurement of coronary artery in-stent density, and significantly underestimates the true in-stent diameter compared to QCA.

Adult↗
PubMed2006

Acute gastrointestinal bleeding: detection of source and etiology with multi-detector-row CT.

This study was conducted to determine the ability of multi-detector-row computed tomography (CT) to identify the source and etiology of acute gastrointestinal bleeding. Eighteen patients with acute upper (n = 10) and lower (n = 8) gastrointestinal bleeding underwent 4-detector-row CT (n = 6), 16-detector-row CT (n = 11), and 64-slice CT (n = 1) with an arterial and portal venous phase of contrast enhancement. Unenhanced scans were performed in nine patients. CT scans were reviewed to determine conspicuity of bleeding source, underlying etiology, and for potential causes of false-negative prospective interpretations. Bleeding sources were prospectively identified with CT in 15 (83%) patients, and three (17%) bleeding sources were visualized in retrospect, allowing the characterization of all sources of bleeding with CT. Contrast extravasation was demonstrated with CT in all 11 patients with severe bleeding, but only in 1 of 7 patients with mild bleeding. The etiology could not be identified on unenhanced CT scans in any patient, whereas arterial-phase and portal venous-phase CT depicted etiology in 15 (83%) patients. Underlying etiology was correctly identified in all eight patients with mild GI bleeding. Multi-detector-row CT enables the identification of bleeding source and precise etiology in patients with acute gastrointestinal bleeding.

Acute Disease↗
PubMed2006

In-vivo flow simulation in coronary arteries based on computed tomography datasets: feasibility and initial results.

The purpose of this paper was to non-invasively assess hemodynamic parameters such as mass flow, wall shear stress (WSS), and wall pressure with computational fluid dynamics (CFD) in coronary arteries using patient-specific data from computed tomography (CT) angiography. Five patients (two without atherosclerosis, three with atherosclerosis) underwent retrospectively electrocardiogram (ECG) gated 16-detector row CT using ECG-pulsing and geometric models of coronary arteries were reconstructed for CFD analysis. Blood flow was considered laminar, incompressible, Newtonian, and pulsatile. The mass flow, WSS, and wall pressure were quantified and flow patterns were visualized. The wall pressure continuously decreased towards distal segments and showed pressure drops in stenotic segments. In coronary segments without atherosclerotic wall changes, WSS remained low, even during phases of high flow velocity, whereas in atherosclerotic vessels, the WSS was elevated already at low flow velocities. Stenoses and post-stenotic dilatations led to flow acceleration and rapid deceleration, respectively, including a distortion of flow. Areas of high WSS and high flow velocities were found adjacent to plaques, with values correlating with the degree of stenosis. CFD provided detailed mass flow measurements. CFD analysis is feasible in normal and atherosclerotic coronary arteries and provides the rationale for further investigation of the links between hemodynamic parameters and the significance of coronary stenoses.

Aged↗
PubMed2006

Visualization of congenital thoracic vascular anomalies using multi-detector row computed tomography and two- and three-dimensional post-processing.

Anomalies of the vascular system are caused by false embryogenesis and are therefore present from birth. Single-detector row spiral computed tomography angiography (CTA) and multi-detector row computed tomography angiography (MDCTA) have gained increasing importance in the non-invasive assessment of vascular pathologies and replace conventional angiography in many cases. High-resolution volumetric datasets that are acquired during a single breath-hold give the possibility of two- (2D) and three-dimensional (3D)-post-processing. Due to post-processing, even complex vascular malformations are visualized in an understandable way. Furthermore, CTA, in contrast to conventional angiography, depicts not only the vascular structures but also allows assessment of the surrounding anatomical structures. We present cases of rare congenital anomalies of the thoracic vessels using MDCT with special respect to 2D- and 3D-post-processing.

Algorithms↗
PubMed2006

Accuracy of dual-source CT coronary angiography: First experience in a high pre-test probability population without heart rate control.

The aim of this study was to assess the diagnostic accuracy of dual-source computed tomography (DSCT) for evaluation of coronary artery disease (CAD) in a population with extensive coronary calcifications without heart rate control. Thirty patients (24 male, 6 female, mean age 63.1+/-11.3 years) with a high pre-test probability of CAD underwent DSCT coronary angiography and invasive coronary angiography (ICA) within 14+/-9 days. No beta-blockers were administered prior to the scan. Two readers independently assessed image quality of all coronary segments with a diameter > or =1.5 mm using a four-point score (1: excellent to 4: not assessable) and qualitatively assessed significant stenoses as narrowing of the luminal diameter >50%. Causes of false-positive (FP) and false-negative (FN) ratings were assigned to calcifications or motion artifacts. ICA was considered the standard of reference. Mean body mass index was 28.3+/-3.9 kg/m2 (range 22.4-36.3 kg/m2), mean heart rate during CT was 70.3+/-14.2 bpm (range 47-102 bpm), and mean Agatston score was 821+/-904 (range 0-3,110). Image quality was diagnostic (scores 1-3) in 98.6% (414/420) of segments (mean image quality score 1.68+/-0.75); six segments in three patients were considered not assessable (1.4%). DSCT correctly identified 54 of 56 significant coronary stenoses. Severe calcifications accounted for false ratings in nine segments (eight FP/one FN) and motion artifacts in two segments (one FP/one FN). Overall sensitivity, specificity, positive and negative predictive value for evaluating CAD were 96.4, 97.5, 85.7, and 99.4%, respectively. First experience indicates that DSCT coronary angiography provides high diagnostic accuracy for assessment of CAD in a high pre-test probability population with extensive coronary calcifications and without heart rate control.

Adult↗
PubMed2006

Noninvasive coronary angiography with 64-section CT: effect of average heart rate and heart rate variability on image quality.

PURPOSE: To evaluate prospectively the effect of average heart rate and heart rate variability on image quality at 64-section computed tomographic (CT) coronary angiography. MATERIALS AND METHODS: The study protocol had local ethics committee approval; written informed consent was obtained. There were 125 patients (45 women, 80 men; mean age, 59.9 years +/- 12.9 [standard deviation]; 79 receiving beta-blockers) who underwent 64-section CT coronary angiography with retrospective electrocardiographic gating. Data sets were reconstructed in 5% steps from 20% to 80% of R-R interval. Heart rate variability was calculated as 1 standard deviation from mean rate during scanning. Two observers rated image quality of each coronary segment at least 1.5-mm diameter (1 = no motion artifacts, 5 = not evaluative). Repeated analysis of variance measurements were performed to evaluate quantitative parameters. Pearson correlation analysis was performed to compare image quality in each patient with average heart rate and heart rate variability. RESULTS: Average heart rate was 63.3 beats per minute +/- 13.1, with variability of 3.2 beats per minute +/- 2.1. Diagnostic image quality (score < or = 3) was attained in 1821 of 1836 segments at the best reconstruction interval. There was no correlation between mean heart rate and image quality for all segments of the right coronary and left anterior descending arteries, but there was a significant correlation for left circumflex artery (r = 0.33, P < .05). Heart rate variability was correlated with image quality overall (r = 0.75, P < .001) and for each coronary artery. Heart rate was less variable and image quality was better (P < .05) in patients receiving beta-blockers. Best image quality was obtained in diastole with heart rate less than 80 beats per minute and in systole with faster heart rate. CONCLUSION: Coronary angiography with 64-section CT provides diagnostic image quality within a wide range of heart rates. Reducing average heart rate and heart rate variability is beneficial for reducing artifacts.

Adult↗
PubMed2006

Assessment of the abdominal aorta and its visceral branches by contrast-enhanced dynamic volumetric hepatic parallel magnetic resonance imaging: feasibility, reliability and accuracy.

The purpose of this study was to evaluate a new three-dimensional gradient-echo (GRE) MR sequence performed with a parallel acquisition technique to shorten breath-hold times (parallel GRE MRI) in the detection of arterial variants and stenosis of the abdominal aorta and its visceral branches. A total of 102 patients underwent dynamic parallel GRE MRI, timed to the arterial phase by a test bolus (mean breath-hold time, 17 s). For both quantitative and qualitative analysis, the abdominal aorta and its visceral branches were divided into 13 arterial segments. In a subanalysis of 55/102 patients, the accuracy of parallel GRE MRI compared to MDCT in the detection arterial variants and stenosis was calculated for two independent readers. Mean SNRs and CNRs were 47.2 and 35.6, respectively. Image quality was rated good or excellent in 1,234/1,326 segments (93%). Hepatic and renal arterial variants were identified with an accuracy of 93 and 95%, respectively (reader 1) and 98 and 100%, respectively (reader 2). Both readers detected arterial stenosis with an accuracy of 98%. Interobserver agreement was good to excellent for the detection of hepatic (kappa=0.69) and renal (kappa=0.92) variants and for the diagnosis of stenosis (kappa=0.96). Dynamic three-dimensional parallel GRE MRI is feasible and allows a reliable and accurate diagnosis of arterial variants and stenosis of the abdominal aorta and its visceral branches in a short breath-hold-time.

Adult↗
PubMed2006

Aortic stenosis: comparative evaluation of 16-detector row CT and echocardiography.

PURPOSE: To prospectively evaluate whether planimetric measurements of aortic valve area (AVA) with 16-detector row computed tomography (CT) allow classification of aortic stenosis (AS). MATERIALS AND METHODS: The study had institutional review board approval; patients gave informed consent. Twenty patients (11 men, nine women; mean age, 63 years) with AS and 20 patients (10 men, 10 women; mean age, 65 years) without underwent transthoracic echocardiography (TTE), transesophageal echocardiography (TEE), and retrospectively electrocardiographically gated 16-detector row CT. Twenty CT data sets were reconstructed in 5% steps of R-R interval; data analysis was performed with four-dimensional software. Maximum AVA in systole planimetrically measured with CT (AVA(CT)) was compared with AVA planimetrically measured with TEE (AVA(TEE)), AVA calculated with the continuity equation and TTE (AVA(TTE)), and transvalvular pressure gradients determined with the Bernoulli equation and TTE. Correlations among AVA(CT), AVA(TTE), AVA(TEE), and transvalvular pressure gradients were tested with bivariate regression analysis; agreement between methods was assessed with the Bland-Altman method. RESULTS: In patients without AS, mean AVA(CT) was 3.56 cm2 +/- 0.66 and mean AVA(TEE) was 3.43 cm2 +/- 0.69. In patients with AS, mean AVA(CT) was 0.89 cm2 +/- 0.35; mean AVA(TEE), 0.86 cm2 +/- 0.35; and mean AVA(TTE), 0.83 cm2 +/- 0.33. Mean transvalvular pressure gradient was 51 mm Hg +/- 22. Significant correlations were present between AVA(CT) and AVA(TEE) (r = 0.99, P < .001), AVA(CT) and AVA(TTE) (r = 0.95, P < .001), and AVA(CT) and transvalvular pressure gradients (r = -0.74, P < .01). Mean differences were -0.08 cm2 (limits of agreement: -0.32, 0.16) for AVA(CT) versus AVA(TEE) and 0.06 cm2 (limits of agreement: -0.15, 0.26) for AVA(CT) versus AVA(TTE). CONCLUSION: Planimetric measurements of AVA with retrospectively electrocardiographically gated 16-detector row CT allow classification of AS that is similar to that achieved with measurements by using echocardiographic methods.

Aged↗
PubMed2006

Prospective intraindividual comparison between respiratory-triggered balanced steady-state free precession and breath-hold gradient-echo and time-of-flight magnetic resonance imaging for assessment of portal and hepatic veins.

The purpose of this study was to compare respiratory-triggered balanced steady-state free precession (bSSFP) with breath-hold contrast-enhanced dynamic two-dimensional (2D) gradient-echo (GRE) and time-of-flight (TOF) magnetic resonance imaging (MRI) for portal and hepatic vein visualization and assessment of portal and hepatic venous variants. Sixty patients with liver disease underwent nonenhanced bSSFP and contrast-enhanced GRE, bSSFP, and TOF imaging. Contrast-to-noise ratios (CNRs) for portal and hepatic veins were measured. Two readers rated the quality of portal and hepatic vein visualization on a 5-point Likert scale. The diagnostic performance of each MRI series in the detection of portal and hepatic venous variants was assessed in 40/60 patients who also underwent contrast-enhanced multidetector-row computed tomography (MDCT). CNRs for portal and hepatic veins were highest on contrast-enhanced bSSFP images. Image quality of portal and hepatic veins was rated higher for nonenhanced bSSFP than for contrast-enhanced GRE (p<0.03) and TOF (p<0.003) and higher for contrast-enhanced than for nonenhanced bSSFP (p<0.003). Compared with MDCT, portal and hepatic venous variants were identified with an accuracy of 99% on bSSFP images, with an excellent interobserver agreement (kappa=0.97). Compared with MDCT, presence of surgically important portal and hepatic venous anatomical variants can be predicted with high accuracy on bSSFP images.

Adult↗
PubMed2006

Optimal image reconstruction intervals for non-invasive coronary angiography with 64-slice CT.

The reconstruction intervals providing best image quality for non-invasive coronary angiography with 64-slice computed tomography (CT) were evaluated. Contrast-enhanced, retrospectively electrocardiography (ECG)-gated 64-slice CT coronary angiography was performed in 80 patients (47 male, 33 female; mean age 62.1+/-10.6 years). Thirteen data sets were reconstructed in 5% increments from 20 to 80% of the R-R interval. Depending on the average heart rate during scanning, patients were grouped as < 65 bpm (n = 49) and > or = 65 bpm (n = 31). Two blinded and independent readers assessed the image quality of each coronary segment with a diameter > or = 1.5 mm using the following scores: 1, no motion artifacts; 2, minor artifacts; 3, moderate artifacts; 4, severe artifacts; and 5, not evaluative. The average heart rate was 63.3 +/- 13.1 bpm (range 38-102). Acceptable image quality (scores 1-3) was achieved in 99.1% of all coronary segments (1,162/1,172; mean image quality score 1.55 +/- 0.77) in the best reconstruction interval. Best image quality was found at 60% and 65% of the R-R interval for all patients and for each heart rate subgroup, whereas motion artifacts occurred significantly more often (P < 0.01) at other reconstruction intervals. At heart rates < 65 bpm, acceptable image quality was found in all coronary segments at 60%. At heart rates > or = 65 bpm, the whole coronary artery tree could be visualized with acceptable image quality in 87% (27/31) of the patients at 60%, while ten segments in four patients were rated as non-diagnostic (scores 4-5) at any reconstruction interval. In conclusion, 64-slice CT coronary angiography provides best overall image quality in mid-diastole. At heart rates < 65 bpm, diagnostic image quality of all coronary segments can be obtained at a single reconstruction interval of 60%.

Adult↗
PubMed2006

Influence of cardiac hemodynamic parameters on coronary artery opacification with 64-slice computed tomography.

The purpose of this study was to evaluate the influence of ejection fraction (EF), stroke volume (SV), heart rate, and cardiac output (CO) on coronary artery opacification with 64-slice computed tomography (CT). Sixty patients underwent, retrospectively, electrocardiography-gated 64-slice CT coronary angiography. Left ventricular EF, SV, and CO were calculated with semi-automated software. Attenuation values were measured and contrast-to-noise ratios (CNRs) were calculated in the proximal right coronary artery (RCA) and left main artery (LMA). Mean EF during scanning was 61.5+/-12.4%, SV was 63.2+/-15.6 ml, heart rate was 62.5+/-11.8 beats per minute (bpm), and CO was 3.88+/-1.06 l/min. There was no significant correlation between the EF and heart rate and the attenuation and CNR in either coronary artery. A significant negative correlation was found in both arteries between SV and attenuation (RCA r=-0.26, P<0.05; LMA r=-0.34, P<0.01) and between SV and CNR (RCA r=-0.26, P<0.05; LMA r=-0.26, P<0.05). Similarly, a significant negative correlation was found between the CO and attenuation (RCA r=-0.42, P<0.05; LMA r=-0.56, P<0.001) and between the CO and CNR (RCA r=-0.39, P<0.05; LMA r=-0.44, P<0.001). The actual hemodynamic status of the patient influences the coronary artery opacification with 64-slice CT, in that vessel opacification decreases as SV and CO increase.

Adult↗
PubMed2006

CT angiography of peripheral arterial bypass grafts: Accuracy and time-effectiveness of quantitative image analysis with an automated software tool.

RATIONALE AND OBJECTIVES: Qualitative analysis of computed tomography (CT) angiography data often is limited by intra- and interobserver variability. The purpose of this study was to evaluate the time-effectiveness and accuracy of a quantitative CT angiography data analysis using automated software in comparison with qualitative axial and coronal CT image reading in patients with peripheral bypass grafts. MATERIALS AND METHODS: Twenty-eight patients with 33 saphenous bypass grafts underwent 4-channel (n = 21) and 16-channel (n = 7) CT angiography. Two readers evaluated in consensus the CT data qualitatively on axial and coronal reconstructions and with the software regarding the presence of graft stenoses, aneurysmal changes, and arteriovenous fistulas. The time for data analysis was taken and the accuracy was compared with the results from digital subtraction angiography (DSA). RESULTS: No significant difference was present between data analysis time using axial and coronal CT images (4.9 +/- 1.5 minutes) and when using the software tool (5.5 +/- 1.4 minutes). Good (kappa = 0.652) to excellent (kappa = 1.000) intermodality agreement was present between qualitative and quantitative CT analysis regarding graft-related abnormalities. Sensitivity and specificity for diagnosing stenoses, aneurysms, and fistula did not differ significantly (P > .025) between qualitative CT image reading and the automated software tool. CONCLUSIONS: CT angiography analysis of peripheral bypass grafts using an automated software tool is similar regarding time-effectiveness and accuracy when compared with qualitative CT data analysis on axial and coronal images. It may assist in determining the significance of an abnormality and can yield objective morphometric data of vessel calibers.

Algorithms↗
PubMed2006

Effects of posture on the physiology of gastric emptying: a magnetic resonance imaging study.

OBJECTIVE: Gastric contents empty from the stomach despite frequent changes in body position. The mechanism that maintains gastric emptying independent of position is poorly understood. The aim of this study was to determine the effects of body position on gastric emptying and motor function. MATERIAL AND METHODS: Twelve volunteers were investigated in seated position (SP) and upside-down position (UDP) after ingestion of 300 ml water. Magnetic resonance imaging provided a non-invasive assessment of gastric emptying and volumes, intragastric distribution and peristaltic function. RESULTS: A marked difference in distal/proximal intragastric distribution between UDP and SP was present (7% versus 40%; p < 0.01). Gastric-emptying time was similar but emptying pattern was linear in UDP and exponential in SP. Peristalsis was slower in UDP than SP (2.75 versus 2.96 min-1; p < 0.01), but no correlation was found between peristaltic frequency and the rate of gastric emptying in either position. Postprandial volume response (gastric relaxation) was greater in UDP than SP (280 versus 250 ml; p < 0.05). A correlation was found between gastric relaxation and gastric-emptying time in SP (r2=0.46) but not in UDP. CONCLUSIONS: The stomach maintains the rate of gastric emptying despite radical changes in body position and intragastric distribution of gastric contents. In SP, hydrostatic pressure (modulated by gastric tone) dictates the gastric emptying. In UDP, gastric emptying also appears to be mediated by continuous adaptation of gastric tone. These findings provide support for the hypothesis that the mechanism of gastric emptying resembles a "pressure pump" rather than a "peristaltic pump".

Adult↗
PubMed2006

Thick maximum intensity projections for the assessment of left ventricular function with 64-slice computed tomography.

OBJECTIVE: The objective of this study was to assess the accuracy of thick maximum intensity projections (MIP) from computed tomography (CT) data sets mimicking projection images from biplane ventriculography for evaluation of left ventricular (LV) parameters. MATERIALS AND METHODS: Fifty-eight patients underwent 64-slice CT. Multiphase images were reconstructed in 10% steps of the RR interval. MIP images (70-mm thickness) of the contrast-enhanced LV in fixed 30 degrees right anterior oblique (RAO)/60 degrees left anterior oblique (LAO) and in adapted short-/long-axis planes were reconstructed. LV parameters were calculated using the area-length method formula. Three-dimensional assessment with semiautomated software served as reference standard. RESULTS: Use of thick MIP reconstructions had a high intermethod reliability (86-94%) compared with the 3-dimensional approach. Smaller measurement errors were found for thick MIP reconstructions in adapted short-/long-axis planes. A significant projection error (3.0%, P < 0.001) of thick MIP reconstructions was found using fixed 30 degrees RAO/60 degrees LAO compared with adapted short-/long-axis reconstructions. CONCLUSION: Thick MIP reconstructions with adapted short-/long-axis planes allow an accurate assessment of LV parameters compared with the established 3-dimensional method.

Adult↗
PubMed2006

Characteristics of displaceable and nondisplaceable meniscal tears at kinematic MR imaging of the knee.

PURPOSE: To prospectively determine if kinematic magnetic resonance (MR) imaging of the knee may demonstrate displacement of menisci with tears and, if so, to characterize displaceable and nondisplaceable meniscal tears. MATERIALS AND METHODS: The study was approved by the hospital's review board, and informed consent was obtained. Forty-two patients (30 men, 12 women; mean age, 36.9 years) with 43 arthroscopically documented meniscal tears visible at 1.5-T MR imaging underwent kinematic MR imaging with an open-configuration 0.5-T MR imager with their knees in supine neutral, supine with 90 degrees flexion and external or internal rotation, and upright weight-bearing positions. Analysis of meniscal movement was performed in different knee positions in the coronal MR imaging plane. Meniscal displacement--that is, meniscal movement of 3 mm or more (in the medial direction for the medial meniscus, in the lateral direction for the lateral meniscus)--was compared with the patient's pain level as assessed with a visual analog scale by using analysis of variance. RESULTS: Between the different knee positions, meniscal displacement of 3 mm or more (displaceable meniscal tears) was noted in 18 (42%) of 43 menisci with tears. Simultaneous occurrence of grade II or III ipsilateral collateral ligament lesions was present in all 18 displaceable meniscal tears, whereas a normal-appearing collateral ligament or collateral ligament lesion (grade I) was present in 22 of 25 nondisplaceable tears (P < .05). Displaced menisci most commonly had complex, radial, or longitudinal tear configurations (16 of 18, 89%). Patients with displaceable meniscal tears had significantly more pain than did patients with nondisplaceable meniscal tears (P < .001), independent of the concomitant knee abnormalities. CONCLUSION: Displaceable meniscal tears usually have longitudinal, radial, or complex configurations; such tears are associated with substantial ipsilateral collateral ligament lesions and pain.

Adolescent↗
PubMed2005

Mitral regurgitation: quantification with 16-detector row CT--initial experience.

PURPOSE: To prospectively determine if retrospectively electrocardiographic (ECG)-gated multi-detector row computed tomography (CT) with a 16-detector row CT scanner can depict mitral regurgitation and enable quantification of the severity of the disease. MATERIALS AND METHODS: The study had institutional review board approval, and patients gave informed consent. Nineteen patients with mitral regurgitation (10 men, nine women; mean age, 66 years +/- 9 [standard deviation]; range, 41-83 years) and 25 patients without mitral regurgitation (14 men, 11 women; mean age, 68 years +/- 9; range, 43-83 years) as determined with transesophageal color Doppler echocardiography and ventriculography underwent retrospectively ECG-gated 16-detector row CT. Twenty CT data sets covering the entire mitral valve apparatus were reconstructed in 5% steps of the R-R interval for each patient, and data analysis was performed with four-dimensional software. Using planimetry, two readers measured in consensus the area of the regurgitant orifice during systole. These measurements were compared with semiquantitative data from transesophageal echocardiography and ventriculography by using Spearman rank order correlation coefficients. RESULTS: In the 25 patients without mitral regurgitation, no regurgitant orifice during systole could be detected with multi-detector row CT. In the 19 patients with mitral regurgitation, a regurgitant orifice could be visualized in all cases. The mean regurgitant orifice area at CT-45 mm(2) +/- 34 (range, 10-148 mm(2))-correlated significantly with the results at transesophageal echocardiography (r = 0.807, P < .001) and ventriculography (r = 0.922, P < .001). CONCLUSION: Planimetric measurements of the regurgitant orifice area at retrospectively ECG-gated 16-detector row CT enable quantification of mitral regurgitation.

Adult↗
PubMed2005

Coronal thick CT reconstruction: an alternative for initial chest radiography in trauma patients.

It has been proposed that the imaging workup of trauma patients be accelerated by omitting the initial chest radiography (CR) and directly performing a computed tomography (CT); however, the baseline CR is then lacking. The purpose of this study was to assess if coronal thick reconstructions generated from chest CT could present an adequate alternative for CR. Sixty trauma patients underwent bedside CR and multidetector row chest CT in the emergency room. The image quality of thoracic anatomical structures, the diagnostic accuracy for chest pathology, and the depiction of indwelling devices were assessed on both modalities. Main pulmonary arteries and perihilar bronchi were equally visualized with both modalities. Central bronchi, retrocardial lung parenchyma, diaphragm, descending aorta, and vertebral pedicles were better visualized on thick CT reconstructions, whereas peripheral lung vessels were better depicted on CR (p<0.05). The accuracy to delineate various pathological findings did not differ between both modalities, except for a higher sensitivity to diagnose bronchial cuffing on CR (p<0.05). The location of indwelling devices was similarly and correctly depicted with both modalities. Coronal thick CT reconstructions provide a similar image quality and diagnostic accuracy compared with CR. These reconstructions may serve as an equivalent baseline image in trauma patients in whom emergency radiological evaluation has to be accelerated.

Adolescent↗