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1.
Eur J Radiol ; 154: 110432, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35839747

ABSTRACT

PURPOSE: The aim of this study was to compare cancer detection by targeted fusion-guided biopsy with systematic biopsy, and to evaluate the value of combined biopsy, in a daily clinical practice scenario. Furthermore, we aimed to assess the influence of previous biopsies on cancer detection. METHODS: In this retrospective single-centre study, we evaluated 524 cases of combined biopsy of the prostate from October 2015 to December 2018. All men had a clinical suspicion for prostate cancer due to an elevated PSA and/or a suspicious digital rectal examination and underwent a multiparametric MRI of the prostate read by one out of 6 experienced radiologists. In all cases, fusion-guided biopsy of the prostate was consecutively followed by systematic 12-core biopsy in the same session at the same urological department performed by one out of 5 experienced urologists. RESULTS: In 270/524 (51.5%) cases, cancer was found using combined biopsy. Systematic biopsy alone detected cancer in 205/524 (39.1%) and clinically significant cancer in 137/524 (26.1%) cases. Fusion-guided biopsy alone detected 227/524 (43.3%) and clinically significant cancer in 150/524 (28.6%) cases. A histological upgrade of the Gleason score by fusion-guided biopsy was noted in 20/270 (7.4%) of all cancers found and by systematic biopsy in 31/270 (11.5%). Of all positive cases (clinically insignificant and significant cancer), 65/270 (24.1%) were detected only by fusion-guided biopsy, whereas 43/270 (15.9%) were detected only by systematic biopsy. CONCLUSIONS: Fusion-guided biopsy can detect more cases of prostate cancers than systematic biopsy alone, especially clinically significant cancer. However, the combination of both biopsy methods improves the detection rate and can help to identify clinically significant cancer.


Subject(s)
Magnetic Resonance Imaging, Interventional , Prostatic Neoplasms , Humans , Image-Guided Biopsy/methods , Magnetic Resonance Imaging/methods , Male , Neoplasm Grading , Prospective Studies , Prostate/diagnostic imaging , Prostate/pathology , Prostatic Neoplasms/pathology , Retrospective Studies , Ultrasonography, Interventional
2.
Eur Radiol ; 30(8): 4295-4305, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32242275

ABSTRACT

OBJECTIVES: Previous studies have shown that split-bolus protocols in virtual non-contrast (VNC) reconstructions of dual-energy computed tomography (DE-CT) significantly decrease radiation dose in patients with urinary stone disease. To evaluate the impact on kidney stone detection rate of stone composition, size, tube voltage, and iodine concentration for VNC reconstructions of DE-CT. METHODS: In this prospective study, 16 kidney stones of different sizes (1.2-4.5 mm) and compositions (struvite, cystine, whewellite, brushite) were placed within a kidney phantom. Seventy-two scans with nine different iodine contrast agents/saline solutions with increasing attenuation (0-1400 HU) and different kilovoltage settings (70 kV/150 kV; 80 kV/150 kV; 90 kV/150 kV; 100 kV/150 kV) were performed. Two experienced radiologists independently rated the images for the presence and absence of stones. Multivariate classification tree analysis and descriptive statistics were used to evaluate the diagnostic performance. RESULTS: Classification tree analysis revealed a higher detection rate of renal calculi > 2 mm in size compared with that of renal calculi < 2 mm (84.7%; 12.7%; p < 0.001). For stones with a diameter > 2 mm, the best results were found at 70 kV/Sn 150 kV and 80 kV/Sn 150 kV in scans with contrast media attenuation of 600 HU or less, with sensitivity of 99.6% and 96.0%, respectively. A higher luminal attenuation (> 600 HU) resulted in a significantly decreased detection rate (91.8%, 0-600 HU; 70.7%, 900-1400 HU; p < 0.001). In our study setup, the detection rates were best for cystine stones. CONCLUSION: Scan protocols in DE-CT with lower tube current and lower contrast medium attenuation show excellent results in VNC for stones larger than 2 mm but have limitations for small stones. KEY POINTS: • The detection rate of virtual non-contrast reconstructions is highly dependent on the surrounding contrast medium attenuation at the renal pelvis and should be kept as low as possible, as at an attenuation higher than 600 HU the VNC reconstructions are susceptible to masking ureteral stones. • Protocols with lower tube voltages (70 kV/Sn 150 kV and 80 kV/Sn 150 kV) improve the detection rate of kidney stones in VNC reconstructions. • The visibility of renal stones in virtual non-contrast of dual-energy CT is highly associated with the size, and results in a significantly lower detection rate in stones below 2 mm.


Subject(s)
Contrast Media , Image Processing, Computer-Assisted/methods , Kidney Calculi/diagnostic imaging , Tomography, X-Ray Computed/methods , Calcium Oxalate , Calcium Phosphates , Cystine , Humans , Iodine , Phantoms, Imaging , Prospective Studies , Radiation Dosage , Struvite , Urinary Calculi
3.
Eur Radiol ; 29(7): 3617-3625, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30888484

ABSTRACT

OBJECTIVES: The aim of this study was to assess the objective and subjective image characteristics of monoenergetic images (MEI[+]), using a noise-optimized algorithm at different kiloelectron volts (keV) compared to polyenergetic images (PEI), in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: This retrospective, institutional review board-approved study included 45 patients (18 male, 27 female; mean age 66 years; range, 42-96 years) with PDAC who had undergone a dual-energy CT (DECT) of the abdomen for staging. One standard polyenergetic image (PEI) and five MEI(+) images in 10-keV intervals, ranging from 40 to 80 keV, were reconstructed. Line-density profile analysis, as well as the contrast-to-noise ratio (CNR) of the tumor, the signal-to-noise ratio (SNR) of the regular pancreas parenchyma and the tumor, and the CNR of the three main peripancreatic vessels, was calculated. For subjective quality assessment, two readers independently assessed the images using a 5-point Likert scale. Reader reliability was evaluated using an intraclass correlation coefficient. RESULTS: Line-density profile analysis revealed the largest gradient in attenuation between PDAC and regular tissue in MEI(+) at 40 keV. Low-keV MEI(+)reconstructions at 40 and 50 keV increased CNR and SNR compared to PEI (40 keV: CNR 46.8 vs. 7.5; SNRPankreas 32.5 vs. 15.7; SNRLesion 13.5 vs. 8.6; p < 0.001). MEI(+) at 40 keV and 50 keV were consistently preferred by the observers (p < 0.05), showing a high intra-observer 0.937 (0.92-0.95) and inter-observer 0.911 (0.89-0.93) agreement. CONCLUSION: MEI(+) reconstructions at 40 keV and 50 keV provide better objective and subjective image quality compared to conventional PEI of DECT in patients with PDAC. KEY POINTS: • Low-keV MEI(+) reconstructions at 40 and 50 keV increase tumor-to-pancreas contrast compared to PEI. • Low-keV MEI(+) reconstructions improve objective and subjective image quality parameters compared to PEI. • Dual-energy post-processing might be a valuable tool in the diagnostic workup of patients with PDAC.


Subject(s)
Algorithms , Carcinoma, Pancreatic Ductal/diagnosis , Image Processing, Computer-Assisted/methods , Pancreas/diagnostic imaging , Pancreatic Neoplasms/diagnosis , Radiography, Dual-Energy Scanned Projection/methods , Virtual Reality , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Reproducibility of Results , Retrospective Studies
4.
J Urol ; 191(3): 792-7, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24140845

ABSTRACT

PURPOSE: We evaluated a dual energy, split bolus computerized tomography protocol that provides virtual noncontrast, parenchymal and urographic phases in a single scan. We assessed the sensitivity of the virtual noncontrast phase using this protocol to detect urinary stones compared to the gold standard of the true noncontrast phase. MATERIALS AND METHODS: We prospectively enrolled in the study 81 patients who underwent unenhanced single energy computerized tomography at 120 kV/200 mA as well as contrast enhanced dual energy computerized tomography on a Somatom® Definition Flash-CT (tube A 80 kV/233 mA and tube B SN 140 kV/180 mA with 1/0.8 mm slice thickness). For the split bolus protocol 400 mg/ml Iomeron® were injected at 2 time points, that is 15 ml 10 minutes before the scan and 80 ml 65 seconds before the scan. In a consensus reading 2 readers evaluated the presence and diameter of stones on the true and virtual noncontrast phases. RESULTS: Of the 350 stones noted on the true noncontrast phase we found 289 on the virtual noncontrast phase as well as 13 false-positive and 66 false-negative stones. Sensitivity was 98.4%, 89.8% and 82.6% per patient, segment and stone, respectively. The diameter measured on the virtual noncontrast phase corresponded to a mean ± SD 92.5% ± 31.6% of the diameter on the true noncontrast phase. The mean effective dose was 4.8 ± 1.8 and 10.5 ± 3.7 mSv for the true and virtual noncontrast phases, respectively. CONCLUSIONS: The proposed protocol allows for combining 3 phases in a single scan while still enabling the detection of urinary stones at high sensitivity. This technique halves the radiation dose and provides the surgeon with better anatomical information on the calyceal system. Therefore, it is a valuable diagnostic tool for kidney stone treatment planning and followup.


Subject(s)
Contrast Media , Iopamidol/analogs & derivatives , Tomography, X-Ray Computed/methods , Urinary Calculi/diagnostic imaging , Female , Humans , Male , Middle Aged , Prospective Studies , Radiation Dosage
5.
Oral Oncol ; 50(3): 221-7, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24373911

ABSTRACT

OBJECTIVES: The aim was to investigate the image quality of dual-energy computed-tomography (DECT) compared to single-energy images at 80 kV and 140 kV in oral tumors. MATERIALS AND METHODS: Forty patients underwent a contrast-enhanced DECT scan on a definition flash-CT. Four reconstructions (80 kV, 140 kV, mixed (M), and optimum-contrast (OC)) were assessed by four blinded readers for subjective image quality (10-point scale/10=best). For objective quality assessment, linear attenuation measurements (line density profiles (LDP)) were positioned at the tumor margin, and the difference between minimum and maximum was calculated. Signal-to-noise ratios (SNR) were measured in the tongue. RESULTS: The mean image quality for all readers was 5.1±0.3, 8.4±0.3, 8.1±0.2, and 8.3±0.2 for the 140 kV, 80 kV, M, and OC, respectively (P<001 between 140 kV and all others). The mean difference between the minimum and maximum within the LDP was 139.4±59.0, 65.7±29.5, 105.1±46.5, and 118.7±59.4 for the 80 kV, 140 kV, M, and OC, respectively (P<001). The SNR for the tongue was 3.8±2.1, 3.8±2.1, 4.2±2.4, and 4.1±2.3 for the 80 kV, 140 kV, M, and OC, respectively. DISCUSSION: DECT of oral tumors offers high image quality, with subjectively rated image quality and attenuation contrast at the tumor margin similar to that of 80 kV; DECT, however, provides a significantly higher SNR compared to 80 kV.


Subject(s)
Carcinoma, Squamous Cell/diagnostic imaging , Carcinoma, Verrucous/diagnostic imaging , Mouth Neoplasms/diagnostic imaging , Radiographic Image Enhancement/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Artifacts , Contrast Media , Dental Restoration, Permanent/adverse effects , Female , Humans , Male , Middle Aged , Reproducibility of Results , Signal-To-Noise Ratio , Young Adult
6.
AJR Am J Roentgenol ; 201(2): W227-34, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23883237

ABSTRACT

OBJECTIVE: The purpose of this study was to use second-generation dual-source CT to assess the influence of size, degree of stenosis, luminal contrast attenuation, and plaque geometry on stenosis quantification in a coronary artery phantom. MATERIALS AND METHODS: Six vessel phantoms with three outer diameters (2, 3, and 4 mm), each containing three radiolucent plaques (72.2 HU) that simulated eccentric and concentric 43.8%, 75%, and 93.8% stenoses were made with a 3D printer system. These phantoms were filled with an iodine-saline solution mixture at luminal attenuations of 150, 200, 250, 300, and 350 HU and were attached to a cardiac motion simulator. Dual-source CT was performed with a standardized ECG-gated protocol (120 kV, 360 mAs per rotation) at a simulated heart rate of 70 beats/min. Two independent readers quantified the degree of stenosis using area-based measurements. RESULTS: All measurements were highly reproducible (intraclass correlation, ≥ 0.791; p < 0.001). The mean measured degree of stenosis for a phantom with a 3-mm outer diameter at 250-HU luminal attenuation was 49.0% ± 10.0% for 43.8% stenosis, 71.7% ± 9.6% for 75.0% stenosis, and 85.4% ± 5.9% for 93.8% stenosis. With decreasing phantom size, measurement error increased for all degrees of stenosis. The absolute error increased for measurements at a low luminal attenuation of 150 HU (p < 0.001) and for low-grade stenoses compared with medium-and high-grade stenoses (p < 0.001). CONCLUSION: The results are an overview of factors that influence stenosis quantification in simulated coronary arteries. Dual-source CT is highly reproducible and accurate for quantification of low-density stenosis in vessels with a diameter of 3 mm and attenuation of at least 200 HU for different degrees of stenosis and plaque geometry.


Subject(s)
Coronary Stenosis/diagnostic imaging , Tomography, X-Ray Computed/methods , Analysis of Variance , Cardiac-Gated Imaging Techniques , Equipment Design , Humans , Phantoms, Imaging , Radiographic Image Interpretation, Computer-Assisted , Reproducibility of Results
7.
Radiology ; 267(2): 522-30, 2013 May.
Article in English | MEDLINE | ID: mdl-23238153

ABSTRACT

PURPOSE: To retrospectively assess the detection rate for intracranial hematomas achieved with use of curved maximum intensity projections (MIPs) that parallel the inner table of the skull compared with the rate achieved by reading transverse sections of computed tomography (CT) only. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board, which waived informed consent. A total of 314 consecutive patients who underwent CT for cranial trauma (155 male, 159 female; mean age ± standard deviation, 58 years ± 24 [range, 2-98 years]) were included. The algorithm unfolded the meningeal spaces into four images per patient. Four radiologists independently evaluated all cases. Hematomas less than 3 mm thick were considered thin. Radiologists were blinded to patient names, and patient and group orders were randomly assigned. The results were compared with a reference standard built by two experts. Logistic regression with repeated measurements was used for statistical analysis. RESULTS: Use of the reference standard helped confirm 121 intracranial hematomas in 39 patients. For all readers, reading time for hematoma detection was significantly shorter (3-5 times shorter, P < .001) for curved MIPs. Mean lesion-based detection rate for all readers was 80% (193 of 242) for transverse sections and 83% (200 of 242) for curved MIPs. For thin hematomas, the mean detection rate increased from 20% (eight of 40) with transverse sections to 83% (33 of 40) with curved MIPs. CONCLUSION: Curved MIPs of the meningeal spaces may shorten detection time for epidural and subdural hematomas, increase sensitivity (especially for thin hematomas), and reduce the required operator experience for detection.


Subject(s)
Hematoma, Subdural/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Logistic Models , Male , Middle Aged , Radiographic Image Interpretation, Computer-Assisted , Retrospective Studies
8.
Melanoma Res ; 22(4): 320-5, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22713795

ABSTRACT

Primary melanoma of the urinary bladder is a rare subentity of melanoma. The same applies for melanoma of the rhabdoid histopathologic phenotype. A female patient was initially diagnosed with melanoma of unknown origin caused by macroscopic lymph node metastasis in the left inguinal and parailiacal regions. Because of the extent of the disease, radical surgery could not be performed. The patient underwent systemic chemotherapy with dacarbazine, followed by the experimental compound tasisulam. Upon sudden macrohematuria, cystoscopy showed a large infiltrating tumorous structure located on the left side of the urinary bladder. Clinically, the amelanotic tumor showed endophytic growth into the lumen; on the histopathological specimen, the growth pattern was partially undermining the urothelium, which is commonly observed in primary melanoma of the urinary bladder. Cytologically, the tumor cells were classified as rhabdoid melanoma, a very rare variant of melanoma, which is commonly amelanotic and expresses S100, vimentin and Ncam. Mutational analysis showed positive results for BRAF V600E. After detecting the primary melanoma, the patient received anti-CTLA4 antibody treatment with 3 mg/kg ipilimumab, through which a partial response was achieved. Past computed tomography scans should be re-evaluated for suspicious lesions, and cystoscopy should be included in the clinical workup if the pattern of metastasis is congruent with the drainage sites of the urinary bladder.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Melanoma/drug therapy , Rhabdoid Tumor/drug therapy , Urinary Bladder/drug effects , Amino Acid Sequence , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/adverse effects , Female , Humans , Ipilimumab , Melanoma/pathology , Middle Aged , Molecular Sequence Data , Rhabdoid Tumor/pathology , Urinary Bladder/pathology
9.
Respiration ; 83(5): 391-9, 2012.
Article in English | MEDLINE | ID: mdl-22469636

ABSTRACT

BACKGROUND: Although chronic obstructive pulmonary disease (COPD) is amongst the leading causes of morbidity and mortality, no biomarkers for its early detection are known. We have recently demonstrated that COPD is accompanied by elevated serum heat shock protein (HSP) 27 levels as compared to a control population. OBJECTIVES: In an open prospective study, we investigated whether elevated HSP27 levels are associated with the early radiological signs of COPD, i.e., air trapping (AT), emphysema (E) and impaired lung function. METHODS: In total, 120 apparently healthy smokers underwent lung function testing and serum sampling. Serum levels of HSP27, phospho-HSP27, CXCR2 chemokines and proteins related to inflammation, tissue remodeling and apoptosis were evaluated by ELISA. Of these 120 subjects, 94 voluntarily underwent a high-resolution computed tomography scan. RESULTS: AT or AT and E were detected in 57.45%. Subjects with AT and E (n = 23) showed significantly higher HSP27 levels than those without any pathology [i.e., nothing abnormal detected (NAD)] (4,618 +/- 1,677 vs. 3,282 +/- 1,607 pg/ml; p = 0.0081). In a univariate logistic regression model including NAD and AT and E, the area under the curve of HSP27 in the receiver-operating-characteristic curve was 0.724, (0.594­0.854, 95% CI; p = 0.0033). Interestingly, proinflammatory IL-8 was elevated in those subjects with evidence of AT and E compared to those with AT and NAD. Lung function did not correlate with increased HSP27 levels or pathological radiological findings. CONCLUSIONS: HSP27 serum levels correlated with the early radiological signs of COPD, whereas lung function did not match with radiological findings or HSP27 serum levels. Serum HSP27 levels may serve as a potential marker to identify the early signs of COPD independent of lung function in young smokers.


Subject(s)
HSP27 Heat-Shock Proteins/blood , Lung/diagnostic imaging , Pulmonary Disease, Chronic Obstructive/diagnosis , Smoking/adverse effects , Adult , Biomarkers/blood , Early Diagnosis , Female , Humans , Interleukin-8/blood , Male , Prospective Studies , Pulmonary Disease, Chronic Obstructive/blood , ROC Curve , Respiratory Function Tests , Sensitivity and Specificity , Tomography, X-Ray Computed
10.
Eur J Radiol ; 81(3): e398-405, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22236702

ABSTRACT

PURPOSE: To evaluate the reliability of attenuation values in virtual non-contrast images (VNC) reconstructed from contrast-enhanced, dual-energy scans performed on a second-generation dual-energy CT scanner, compared to single-energy, non-contrast images (TNC). MATERIALS AND METHODS: Sixteen phantoms containing a mixture of contrast agent and water at different attenuations (0-1400 HU) were investigated on a Definition Flash-CT scanner using a single-energy scan at 120 kV and a DE-CT protocol (100 kV/SN140 kV). For clinical assessment, 86 patients who received a dual-phase CT, containing an unenhanced single-energy scan at 120 kV and a contrast enhanced (110 ml Iomeron 400 mg/ml; 4 ml/s) DE-CT (100 kV/SN140 kV) in an arterial (n=43) or a venous phase, were retrospectively analyzed. Mean attenuation was measured within regions of interest of the phantoms and in different tissue types of the patients within the corresponding VNC and TNC images. Paired t-tests and Pearson correlation were used for statistical analysis. RESULTS: For all phantoms, mean attenuation in VNC was 5.3±18.4 HU, with respect to water. In 86 patients overall, 2637 regions were measured in TNC and VNC images, with a mean difference between TNC and VNC of -3.6±8.3 HU. In 91.5% (n=2412) of all cases, absolute differences between TNC and VNC were under 15HU, and, in 75.3% (n=1986), differences were under 10 HU. CONCLUSIONS: Second-generation dual-energy CT based VNC images provide attenuation values close to those of TNC. To avoid possible outliers multiple measurements are recommended especially for measurements in the spleen, the mesenteric fat, and the aorta.


Subject(s)
Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Contrast Media/administration & dosage , Female , Humans , Male , Middle Aged , Phantoms, Imaging , Radiographic Image Interpretation, Computer-Assisted , Reproducibility of Results , Retrospective Studies , Signal-To-Noise Ratio , User-Computer Interface , Water/administration & dosage
11.
Int J Cardiol ; 146(2): 171-6, 2011 Jan 21.
Article in English | MEDLINE | ID: mdl-19615769

ABSTRACT

OBJECTIVES: We aimed to identify the predictors of left atrial (LA) enlargement by multi-detector computed tomography (CT) and determine its association and predictive value for acute coronary syndrome (ACS). BACKGROUND: LA enlargement is associated with myocardial ischemia and coronary artery disease (CAD) and is a strong predictor for cardiovascular events. These studies were performed primarily with echocardiography. With the rise of cardiac CT, LA volume can be readily measured. METHODS: In 377 emergency department patients with chest pain, we performed 64-slice CT for coronary artery assessment. We derived LA volumes (LAV(max), LAV(min)) and indices (LAVI(max), LAVI(min)) using a threshold-based volumetric method. RESULTS: Subjects, with cardiac risk factors or CAD by CT, had larger LA (ΔLAV(max) 9.1 ml, p=0.004; ΔLAV(min) 8.1 ml, p=0.001; ΔLAVI(max) 3.3 ml/m(2), p=0.03; ΔLAVI(min) 3.4 ml/m(2), p=0.006) than controls. Predictors of LA enlargement were related to risk factors for diastolic dysfunction. ACS risk was greater in patients with top quartile LAV(max) (odds ratio [OR] 3.4, p=0.02) and LAV(min) (OR 4.7, p=0.01) than lowest quartile, but not when indexed. Similarly, the predictive values of LA volumes were incrementally better when added to CT finding of indeterminate stenosis (LAV(max): C statistic 0.62 to 0.70, p=0.046; LAV(min): C statistic 0.65 to 0.73, p=0.008), but not when indexed. CONCLUSIONS: Risk factors related to diastolic dysfunction are independent predictors of LA enlargement. LA enlargement by volumes are associated with a 3-5 fold increase risk for ACS and have incremental value for predicting ACS when added to the CT finding of indeterminate stenosis.


Subject(s)
Acute Coronary Syndrome/diagnostic imaging , Cardiac Volume , Cardiomegaly/diagnostic imaging , Tomography, X-Ray Computed/methods , Acute Coronary Syndrome/epidemiology , Adult , Aged , Cardiomegaly/epidemiology , Cohort Studies , Echocardiography , Female , Heart Atria/diagnostic imaging , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Risk Factors
12.
Invest Radiol ; 45(11): 693-701, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20479650

ABSTRACT

PURPOSE: To determine the reproducibility, accuracy, and predictors of accuracy of computed tomography (CT) angiography to detect and characterize coronary atherosclerotic plaque as compared with intravascular ultrasound. METHODS: Ten ex vivo human coronary arteries were imaged in a moving phantom by dual-source CT (collimation: 0.6 mm, reconstructed slice thickness: 0.4 mm) and intravascular ultrasound (IVUS). Coregistered cross-sections were assessed at 0.4 mm intervals for the presence and composition of atherosclerotic plaque (noncalcified, mixed, and calcified) on CT and IVUS by independent readers to determine reader agreement and diagnostic accuracy. Quantitative measurements of lumen and plaque area, plaque eccentricity, and intimal thickness on IVUS were used to determine predictors for the detection of noncalcified plaque by CT. RESULTS: Within 1002 coregistered cross-sections, the interobserver agreement to detect plaque on CT was K = 0.48, K = 0.42, and K = 1.00 for noncalcified, mixed, and calcified plaque; respectively. The sensitivity and specificity of CT was 57% out of 84% for noncalcified, 32% of 92% for mixed, and 56% of 93% for calcified plaque when compared with IVUS; respectively. Misclassification occurred in 68% of mixed and 43% of noncalcified plaques. The odds of detecting noncalcified plaque in CT independently increased by 56% (95% CI: 47%-77%, P < 0.0001) with every 0.1 mm increase in maximum intimal thickness as measured by IVUS. Detection rate for noncalcified plaques was poor for plaques <1 mm (36%) but excellent for plaques >1 mm maximal intimal thickness (90%). CONCLUSION: Reader agreement and diagnostic accuracy for the detection of coronary atherosclerotic plaque vary with plaque composition. Intimal thickness independently predicts detection of noncalcified plaque by CT with excellent sensitivity for >1 mm thick plaques.


Subject(s)
Coronary Artery Disease/diagnosis , Coronary Vessels/pathology , Tomography, X-Ray Computed/instrumentation , Ultrasonography, Interventional/instrumentation , Aged , Area Under Curve , Confidence Intervals , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/pathology , Coronary Vessels/diagnostic imaging , Female , Humans , Male , Middle Aged , Multivariate Analysis , Odds Ratio , Predictive Value of Tests , ROC Curve , Reproducibility of Results , Sensitivity and Specificity , Tomography, X-Ray Computed/methods
13.
Eur J Radiol ; 75(2): e141-6, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20430558

ABSTRACT

INTRODUCTION: The purpose of this study was to compare a manual and automated 3D volume segmentation tool for evaluation of left atrial (LA) function by 64-slice multidetector-CT (MDCT). METHODS AND MATERIALS: In 33 patients with paroxysmal atrial fibrillation a MDCT scan was performed before radiofrequency-catheter ablation. Atrial function (minimal volume (LAmin), maximal volume (LAmax), stroke volume (SV), ejection fraction (EF)) was evaluated by two readers using a manual and an automatic tool and measurement time was evaluated. RESULTS: Automated LA volume segmentation failed in one patient due to low LA enhancement (103HU). Mean LAmax, LAmin, SV and EF were 127.7 ml, 93 ml, 34.7 ml, 27.1% by the automated, and 122.7 ml, 89.9 ml, 32.8 ml, 26.3% by the manual method with no significant difference (p>0.05) and high Pearsons correlation coefficients (r=0.94, r=0.94, r=0.82 and r=0.85, p<0.0001), respectively. The automated method was significantly faster (p<0.001). Interobserver variability was low for both methods with Pearson's correlation coefficients between 0.98 and 0.99 (p<0.0001). CONCLUSIONS: Evaluation of LA volume and function with 64-slice MDCT is feasible with a very low interobserver variability. The automatic method is as accurate as the manual method but significantly less time consuming permitting a routine use in clinical practice before RF-catheter ablation.


Subject(s)
Atrial Fibrillation/physiopathology , Atrial Function, Left , Catheter Ablation , Heart Atria/diagnostic imaging , Imaging, Three-Dimensional , Tomography, X-Ray Computed , Adult , Aged , Atrial Fibrillation/diagnostic imaging , Atrial Fibrillation/surgery , Female , Humans , Male , Middle Aged , Observer Variation , Radiographic Image Interpretation, Computer-Assisted
14.
J Hypertens ; 28(9): 1959-67, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20498615

ABSTRACT

OBJECTIVE: Cardiac computed tomography (CT) is a state-of-the-art technology that provides an accurate noninvasive method to quantify left ventricular mass for analysis of left ventricular hypertrophy (LVH). We aimed to examine seven ECG-based LVH criteria against two CT indexation criteria for LVH: a CT-specific body surface area cutoff and the obesity-independent height criteria. METHODS: In 333 patients (mean age 53 +/- 12 years, 61% men), 64-slice contrast-enhanced CT was performed and 12-lead surface ECG within 24 h. Left ventricular mass was measured at end-diastole. Using both CT indexation criteria, the cohort was subdivided into patients with LVH and without LVH. The seven ECG criteria for LVH were the Cornell voltage index, Cornell voltage duration product, Cornell/strain index, Sokolow-Lyon index, Romhilt-Estes scores at least 4 and at least 5, and Gubner-Ungerleider. RESULTS: The ECG parameters had high specificities (85-97%) and variable low sensitivities (4-43%) when compared to either CT criteria of LVH. The three Cornell-based methods performed the best (test-positive likelihood ratio: 4.5-6.7), followed by the Sokolow-Lyon and Romhilt-Estes scores (test-positive likelihood ratio: 2.3-4.0). With the exception of the Gubner-Ungerleider criterion, the other six ECG criteria were associated with at least one of the CT-based LVH (adjusted odds ratio 2.4-9.5) and had incremental predictive value beyond that of hypertension history. CONCLUSION: Using cardiac CT as a gold standard for LVH assessment, ECG criteria for LVH have high specificities with the three Cornell-based criteria providing the best test performance for identifying patients with LVH.


Subject(s)
Electrocardiography , Hypertrophy, Left Ventricular/diagnostic imaging , Hypertrophy, Left Ventricular/diagnosis , Tomography, X-Ray Computed , Adult , Aged , Cohort Studies , Electrocardiography/statistics & numerical data , Female , Humans , Male , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/diagnostic imaging , Predictive Value of Tests , Prospective Studies , Tomography, X-Ray Computed/statistics & numerical data
15.
Eur Radiol ; 20(3): 542-8, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19727745

ABSTRACT

PURPOSE: We assessed the accuracy and reproducibility of non-calcified plaque quantification as simulated by a low-density stenosis in vessel phantoms using diameter and area measures, as well as the influence of vessel size and motion on quantification accuracy in dual-source computed tomography (DSCT). METHODS: Four phantoms (2, 2.5, 3, and 4 mm in luminal diameter) made from a radiopaque Lucite (126 +/- 23 Hounsfield units, HU) simulating a fixed radiolucent concentric coronary stenosis (7 +/- 2 HU, 50% luminal narrowing) were connected to a cardiac motion simulator. Stenosis quantification was based on area and diameter measurements. All measurements were highly reproducible (all ICC > or =0.95, p < 0.001). RESULTS: The mean measured degree of stenosis was 38.0 +/- 11.7% for a single diameter measurement, resulting in a mean relative error of 22.0 +/- 18.7%, decreasing with increasing phantom size (31.9 +/- 22.1%; 25.2 +/- 20.9%; 16.3 +/- 12.8%; 14.5 +/- 11.4%; for 2-, 2.5-, 3-, and 4-mm phantoms, respectively; p < 0.0001). Measurement accuracy significantly increased to 13.3 +/- 13.9% by using area measurement (p < 0.0001). The degree of stenosis was not significantly different when comparing a motioned image with an image at rest. CONCLUSION: DSCT enables highly reproducible quantification of low density stenosis, but underestimates the degree of stenosis, especially in small vessels. Area-based measurements reflect the true degree of stenosis with higher accuracy than diameter.


Subject(s)
Coronary Angiography/methods , Coronary Stenosis/diagnostic imaging , Radiography, Dual-Energy Scanned Projection/methods , Tomography, X-Ray Computed/methods , Coronary Angiography/instrumentation , Humans , Motion , Phantoms, Imaging , Radiography, Dual-Energy Scanned Projection/instrumentation , Reproducibility of Results , Sensitivity and Specificity , Tomography, X-Ray Computed/instrumentation
16.
Am Heart J ; 158(4): 562-8, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19781415

ABSTRACT

BACKGROUND: Aortic valve calcification (AVC) is associated with cardiovascular risk factors and coronary artery calcification. We sought to determine whether AVC is associated with the presence and extent of overall plaque burden, as well as to plaque composition (calcified, mixed, and noncalcified). METHODS: We examined 357 subjects (mean age 53 +/- 12 years, 61% male) who underwent contrast-enhanced electrocardiogram-gated 64-slice multidetector computed tomography from the ROMICAT trial for the assessment of presence and extent of coronary plaque burden according to the 17-coronary segment model and presence of AVC. RESULTS: Patients with AVC (n = 37, 10%) were more likely than those without AVC (n = 320, 90%) to have coexisting presence of any coronary plaque (89% vs 46%, P < .001) and had a greater extent of coronary plaque burden (6.4 vs 1.8 segments, P < .001). Those with AVC had >3-fold increase odds of having any plaque (adjusted odds ratio [OR] 3.6, P = .047) and an increase of 2.5 segments of plaque (P < .001) as compared to those without AVC. When stratified by plaque composition, AVC was associated most with calcified plaque (OR 5.2, P = .004), then mixed plaque (OR 3.2, P = .02), but not with noncalcified plaque (P = .96). CONCLUSION: Aortic valve calcification is associated with the presence and greater extent of coronary artery plaque burden and may be part of the later stages of the atherosclerosis process, as its relation is strongest with calcified plaque, less with mixed plaque, and nonsignificant with noncalcified plaque. If AVC is present, consideration for aggressive medical therapy may be warranted.


Subject(s)
Aortic Valve , Calcinosis/diagnostic imaging , Coronary Angiography/methods , Coronary Artery Disease/diagnostic imaging , Heart Valve Diseases/diagnostic imaging , Myocardial Infarction/diagnostic imaging , Tomography, X-Ray Computed/methods , Aged , Calcinosis/complications , Coronary Artery Disease/complications , Female , Follow-Up Studies , Heart Valve Diseases/complications , Humans , Male , Middle Aged , Myocardial Infarction/etiology , Prospective Studies , Reproducibility of Results , Risk Factors
17.
J Hypertens ; 27(12): 2472-82, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19696685

ABSTRACT

OBJECTIVE: Cardiac computed tomography allows for simultaneous assessment of left ventricular mass (LVM) and coronary artery disease (CAD). We aimed to determine whether LVM, LVM index (LVMi), and the left ventricular geometric pattern of concentric remodeling are associated with the extent of CAD in patients without left ventricular hypertrophy. METHODS: In 348 patients from the Rule Out Myocardial Infarction Using Computer Assisted Tomography trial, 64-slice computed tomography was performed and LVM measured at end-diastole. We used three LVM indexation criteria to obtain three cohorts: LVM indexed to body surface area by echocardiography (n = 337) and computed tomography criteria (n = 325), and by height (n = 326). The cohorts were subdivided into concentric remodeling and normal geometry. Extent of coronary plaque was classified based on a 17-segment model, treated as a continuous variable, and stratified into three groups: zero segment, one to four segments, and more than four segments. RESULTS: Patients with more than four segments of coronary plaque had higher LVM (Delta12.8-15.1 g) and LVMi (Delta4.0-5.5 g/m and Delta2.2 g/m) than those without CAD (all P < or = 0.03). After multivariable adjustment, LVM and LVMi remained independent predictors of extent of coronary plaque, with 0.27-0.29 segments more plaque per 20 g increase of LVM (all P = 0.02), 0.32-0.34 segments more plaque per 10 g/m increase of LVMi (both P = 0.02), and 0.80 segments more plaque per 10 g/m increase of LVMi (P = 0.008). Concentric remodeling patients had 1.1-1.3 segments more plaque than those with normal geometry (all P < or = 0.05). Patients with more than four segments of plaque had two-fold increase in odds (all P < or = 0.05) of having concentric remodeling as compared with those without CAD. CONCLUSION: Increased LVM, LVMi, and concentric remodeling are associated with a greater degree of coronary plaque burden in patients without left ventricular hypertrophy. These findings could provide an indication to intensify medical therapy in patients with subclinical CAD and hypertension.


Subject(s)
Coronary Artery Disease/diagnosis , Heart Ventricles/pathology , Hypertrophy, Left Ventricular/diagnosis , Tomography, X-Ray Computed/methods , Ventricular Remodeling , Adult , Aged , Aged, 80 and over , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/physiopathology , Female , Heart Ventricles/diagnostic imaging , Heart Ventricles/physiopathology , Humans , Hypertrophy, Left Ventricular/diagnostic imaging , Hypertrophy, Left Ventricular/physiopathology , Male , Middle Aged , Prospective Studies , Risk Factors , Young Adult
18.
J Cardiovasc Comput Tomogr ; 3(2): 80-7, 2009.
Article in English | MEDLINE | ID: mdl-19332340

ABSTRACT

BACKGROUND: Left atrial (LA) volume is a predictor of cardiovascular events. Information on LA volume is available on contrast-enhanced electrocardiogram (EGC)-gated multidetector computed tomography (MDCT) scans. OBJECTIVE: To assess interobserver and intraobserver reproducibility of 3-dimensional threshold-based volume (3DTV) and 2-dimensional (2D) measurements for the assessment of LA volumes with contrast-enhanced cardiac 64-slice MDCT. METHODS: Contrast-enhanced 64-slice MDCT (0.6-mm slice thickness, 120 kVp, 850 mAseff) was performed in 96 consecutive subjects (mean age 52 years; 48% women) as a subset of the Rule Out Myocardial Infarction using Computer Assisted Tomography trial. Two observers independently measured maximal (LAV(max)) and minimal (LAV(min)) LA volumes with (1) a modified Simpson's method (3DTV) based on delineation of LA areas in axial slices and (2) estimated LA volumes typically used in 2D echocardiography (area length and prolate ellipse). Interobserver and intraobserver reproducibility for each method as well as correlations between the methods were calculated. RESULTS: Interobserver (n = 96) and intraobserver (n = 20) variability was significantly lower for 3DTV (8%) than for area length (13%; P < 0.001) or prolate ellipse (16%; P < 0.001). 2D-based measurements rendered significantly lower LA volumes than did 3DTV (area length: -17% and -22%; prolate ellipse: -43% and -46% for LAV(max) and LAV(min), respectively; P < 0.001 for all). By 3DTV, mean LA volume was 90.4 +/- 24.5 mL for LAV(max) and 52.5 +/- 17.6 mL for LAV(min). CONCLUSION: ECG-gated contrast-enhanced cardiac MDCT offers volumetric assessment of LA volume with excellent reproducibility without additional contrast administration or radiation exposure. 3D measures of LA volume are more reproducible and render larger volumes than 2D-derived estimates, typically used in echocardiography.


Subject(s)
Electrocardiography , Heart Diseases/diagnostic imaging , Tomography, X-Ray Computed , Adult , Atrial Function, Left , Feasibility Studies , Female , Heart Atria/diagnostic imaging , Heart Diseases/physiopathology , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Observer Variation , Predictive Value of Tests , Prospective Studies , Radiographic Image Interpretation, Computer-Assisted , Reproducibility of Results
19.
Atherosclerosis ; 205(2): 481-5, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19230889

ABSTRACT

OBJECTIVE: The aim of the study was to assess differences in the presence, extent, and composition of coronary atherosclerotic plaque burden as detected by coronary multidetector computed tomography (MDCT) between patients with and without diabetes mellitus. METHODS: We compared coronary atherosclerotic plaques (any plaque, calcified [CAP], non-calcified [NCAP, and mixed plaque [MCAP]]) between 144 symptomatic diabetic and non-diabetic patients (36 diabetics, mean age: 54.4+/-12, 64% females) who underwent coronary 64-slice MDCT (Siemens Medical Solutions, Forchheim, Germany) for the evaluation of acute chest pain but proven absence of myocardial ischemia. RESULTS: Patients with diabetes had a higher prevalence of any plaque, CAP, MCAP, and NCAP (p=0.08, 0.07, 0.05, and 0.05, respectively) and a significantly higher extent of any plaque, CAP, MCAP, and NCAP (3.8+/-4.2 vs. 2.0+/-3.2, p=0.01; 3.3+/-4.0 vs. 1.7+/-3.0, p=0.03; 1.4+/-2.6 vs. 0.6+/-1.5, p=0.03; and 1.9+/-3.0 vs. 1.0+/-1.9, p=0.03, respectively) as compared to controls. In addition, patients with diabetes had a significant higher prevalence of significant coronary artery stenosis (42% vs. 14%, p=0.0004) and an approximately 3.5-fold higher risk of significant coronary stenosis independent of the presence of hypertension and BMI (OR: 3.46, 95% CI: 1.37-8.74, p=0.009). CONCLUSION: Patients with diabetes have an approximately 3.5-fold higher risk of coronary stenosis independent of other cardiovascular risk factors and an overall increased coronary atherosclerotic plaque burden.


Subject(s)
Coronary Artery Disease/physiopathology , Diabetes Mellitus/physiopathology , Tomography, X-Ray Computed/methods , Aged , Body Mass Index , Case-Control Studies , Coronary Artery Disease/diagnosis , Coronary Artery Disease/pathology , Coronary Stenosis/pathology , Coronary Vessels/pathology , Diabetes Complications/pathology , Diabetes Mellitus/diagnosis , Female , Humans , Male , Middle Aged , Risk Factors
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