Mean arterial pressure (MAP) augmentation in traumatic spinal cord injuries: Early hyperperfusion treatment influences neurologic outcomes.

CONTEXT: Hyperperfusion therapy, mean arterial blood pressure (MAP) > 85 mmHg, is a recommended treatment of blunt traumatic spinal cord injury (SCI). We hypothesized the first 24 h of MAP augmentation would be most influential on neurological outcomes. DESIGN: This retrospective study from a level 1 urban trauma center dating 1/2017 to 12/2019 included all blunt traumatic spinal cord injured patients receiving hyperperfusion therapy. Patients were grouped as "No improvement" vs "Improvement" measured by change in American Spinal Injury Association (ASIA) score during their hospitalization. MAP values for the first 12, first 24 and last 72 h were compared between the two groups; P < 0.05 was significant. RESULTS: After exclusions, 96 patients underwent hyperperfusion therapy for blunt traumatic SCI, 82 in the No Improvement and 14 in the Improvement group. Groups had similar treatment durations (95.6 and 96.7 h, P = 0.66) and ISS (20.5 and 23, P = 0.45). The area under the curve, calculation, to account for time less than goal and MAP difference from goal, in the No Improvement group was significantly higher (lower and more time below MAP goal) compared to the Improvement group for the first 12 h (40.3 v. 26.1 P = 0.03) with similar findings in the subsequent 12 h of treatment (13-24 h; 62.2 vs 43, P = 0.09). There was no difference between the groups in the subsequent 72 h (25-96 h; 156.4 vs 136.6, P = 0.57). CONCLUSIONS: Hyperperfusion to the spinal cord in the first 12 h correlated significantly with improved neurological outcome in SCI patients.

Bosniak category IIF and III cystic renal lesions: outcomes and associations.

PURPOSE: To evaluate clinical outcomes, pathologic subtypes, metastatic disease rate, and clinical features associated with malignancy in Bosniak category IIF and III cystic renal lesions. MATERIALS AND METHODS: This retrospective study was institutional review board approved and HIPAA compliant. Informed consent was waived. Radiology and hospital information systems were searched for Bosniak IIF and Bosniak III lesions in computed tomographic (CT) reports from January 1, 1994 to August 31, 2009. Patients 18 years and older with unenhanced and contrast material-enhanced CT results and with lesions either surgically resected or with 1 year or more of surveillance were included. Data recorded were history of renal cell carcinoma, number of renal lesions, presence of a coexistent solid renal mass, surgical pathologic findings, and presence of metastatic disease from a renal malignancy. Sixty-two patients with 69 Bosniak IIF lesions and 131 patients with 144 Bosniak III lesions were identified. Proportions from independent groups were compared by using the Fisher exact test; continuous variables were compared by using a two-tailed two-sample t test or a Wilcoxon two-sample test. RESULTS: The malignancy rate of resected Bosniak IIF lesions was 25% (four of 16) and that for Bosniak III lesions was 54% (58 of 107) (P = .03). Thirteen percent (nine of 69) of Bosniak IIF lesions progressed at follow-up, and 50% (four of eight) of these resected cysts were malignant. History of primary renal malignancy, coexisting Bosniak category IV lesion and/or solid renal mass, and multiplicity of Bosniak III lesions were each associated with an increased malignancy rate in Bosniak III lesions. No patients developed locally advanced or metastatic disease from a Bosniak IIF or III lesion. CONCLUSION: Although the malignancy rate in surgically excised Bosniak IIF and Bosniak III cystic renal lesions was 25% and 54%, respectively, in our study, the malignancy rate was higher in patients with a history of primary renal malignancy or coexisting Bosniak IV lesion and/or solid renal neoplasm.

Cardiac MR assessment of aortic regurgitation: holodiastolic flow reversal in the descending aorta helps stratify severity.

PURPOSE: To assess the utility of holodiastolic flow reversal (HDR) in the descending aorta on velocity-encoded cardiac magnetic resonance (MR) images in the stratification of aortic regurgitation (AR) severity. MATERIALS AND METHODS: This study was approved by the institutional review board, with waiver of informed consent. A total of 80 patients (overall mean age, 49 years ± 18 [standard deviation]; 22 women and 58 men) with clinical indication for cardiac MR imaging of the aorta were analyzed retrospectively. Velocity-encoded MR imaging was used to quantify AR and assess for HDR at the level of the middescending aorta. These indexes were compared with a qualitative integrated echocardiographic evaluation of AR severity. Sensitivity and specificity for HDR in the prediction of substantial AR were determined, and logistic regression analysis (with associated odds ratios and C statistics) was performed, with HDR and regurgitant fraction as independent predictors. An additional 42 patients (overall mean age, 48 years ± 21; 12 female and 30 male) were then prospectively evaluated in similar fashion to evaluate a decision model derived from analysis of the first group. RESULTS: HDR predicted severe AR (echo grade, 4) with high sensitivity (100%) and specificity (93%). HDR was highly specific (100%) but had lower sensitivity (61%) for moderate to severe AR (echo grade, 3-4). Integration of HDR and direct AR quantification into a combined stratification model based on analysis of the primary group showed good predictive results in the validation group, with a C statistic of 0.94 for moderate to severe AR and 0.93 for severe AR. CONCLUSION: HDR in the middescending thoracic aorta observed at cardiac MR is indicative of severe AR and can be used in conjunction with quantified regurgitant values obtained from velocity-encoded MR imaging to stratify AR severity.

A comparison of follow-up recommendations by chest radiologists, general radiologists, and pulmonologists using computer-aided detection to assess radiographs for actionable pulmonary nodules.

OBJECTIVE: The primary objective of our study was to compare the effect of a chest radiography computer-aided detection (CAD) system on the follow-up recommendations of chest radiologists, general radiologists, and pulmonologists. MATERIALS AND METHODS: A chest radiography CAD system (RapidScreen 1.1) that has been approved by the U.S. Food and Drug Administration (FDA) and a second-generation version of the system (OnGuard 3.0) not yet approved by the FDA were applied to single frontal radiographs of 200 patients at high risk for lung cancer. One hundred patients had actionable nodules (mean size, 16.9 mm) and 100 patients did not. Six chest radiologists, six general radiologists, and six pulmonologists independently interpreted each image first without CAD and then with CAD during blinded reading sessions. The frequency with which readers correctly referred patients for follow-up tests was measured. Differential effects based on nodule size, shape, location, density, and subtlety were tested with multiplevariable logistic regression. RESULTS: For patients without actionable lesions, pulmonologists showed an increase in their recommendations for follow-up from 0.46 unaided to 0.52 with CAD (p = 0.001), whereas chest and general radiologists had much lower average rates and were not affected by CAD's false marks (0.26 without CAD vs 0.25 with RapidScreen 1.1 and 0.26 with OnGuard 3.0, p ≥ 0.734). CAD improved all readers' detection of moderately subtle lesions (p = 0.013) but did not significantly increase follow-up rates overall for patients with actionable nodules (0.63 unaided vs 0.63 with RapidScreen 1.1, p = 0.795; and 0.63 unaided vs 0.64 with OnGuard 3.0, p = 0.187). CONCLUSION: The effect of CAD on readers' clinical decisions varies depending on the training of the reader. CAD did not improve the performance of chest or general radiologists. Nonradiologists are particularly vulnerable to CAD's false-positive marks.

Assessing tumor response and detecting recurrence in metastatic renal cell carcinoma on targeted therapy: importance of size and attenuation on contrast-enhanced CT.

OBJECTIVE: The aim of this study was to improve response assessment in patients with metastatic renal cell carcinoma (RCC) on antiangiogenic targeted therapy by evaluating changes in both tumor size and attenuation and by detecting unique patterns of contrast enhancement on contrast-enhanced CT (CECT). MATERIALS AND METHODS: Tumor long-axis measurements and volumetric mean tumor attenuation of target lesions on CECT images were correlated with time to progression in 53 patients with metastatic clear cell RCC treated with first-line sorafenib or sunitinib. The frequencies of specific patterns of tumor progression were assessed. The data were used to develop new imaging criteria, the size and attenuation CT (SACT) criteria. CECT findings were evaluated using the SACT criteria, Response Evaluation Criteria in Solid Tumors (RECIST), and modified Choi criteria, and the Kaplan-Meier method was used to estimate survival functions. RESULTS: One or more target metastatic lesions had decreased attenuation of >or=40 HU in 59% of patients with progression-free survival of >250 days (n=44) after initiating targeted therapy; 0% of patients with earlier disease progression (n=9) had this finding. A favorable response based on SACT criteria had a sensitivity of 75% and specificity of 100% for identifying patients with progression-free survival of >250 days, versus 16% and 100%, respectively, for RECIST and 93% and 44% for the modified Choi criteria. CONCLUSION: Objectively measuring changes in both tumor size and attenuation on the first CECT study after initiating targeted therapy for metastatic RCC markedly improves response assessment. Distinct patterns of disease recurrence are seen in patients with metastatic RCC on targeted therapy.

Morphology, Attenuation, Size, and Structure (MASS) criteria: assessing response and predicting clinical outcome in metastatic renal cell carcinoma on antiangiogenic targeted therapy.

OBJECTIVE: The objective of our study was to evaluate response assessment and predict clinical outcome in patients with metastatic renal cell carcinoma (RCC) receiving antiangiogenic targeted therapy. Target lesions were assessed on routine contrast-enhanced CT (CECT) images obtained during the portal venous phase using new response criteria. MATERIALS AND METHODS: Standard CECT examinations of patients with metastatic clear cell RCC on first-line sunitinib or sorafenib therapy (n = 84) were retrospectively evaluated using Mass, Attenuation, Size, and Structure (MASS) Criteria; Response Evaluation Criteria in Solid Tumors (RECIST); Size and Attenuation CT (SACT) Criteria; and modified Choi Criteria. The objective response to therapy was compared with clinical outcomes including time to progression (TTP) and disease-specific survival. The Kaplan-Meier method was used to estimate survival functions. RESULTS: A favorable response according to MASS Criteria had a sensitivity of 86% and specificity of 100% in identifying patients with a good clinical outcome (i.e., progression-free survival of > 250 days) versus 17% and 100%, respectively, for RECIST partial response. The objective categories of response used by MASS Criteria-favorable response, indeterminate response, and unfavorable response-differed significantly from one another with respect to TTP (p < 0.0001, log-rank test) and disease-specific survival (p < 0.0001, log-rank test). CONCLUSION: Assessment of metastatic RCC target lesions on CECT for changes in morphology, attenuation, size, and structure by MASS Criteria is more accurate than response assessment by SACT Criteria, RECIST, or modified Choi Criteria. Furthermore, the use of MASS Criteria for imaging response assessment showed high interobserver agreement and may predict disease outcome in patients with metastatic RCC on targeted therapy.

Feasibility of dual-energy CT in the arterial phase: Imaging after endovascular aortic repair.

OBJECTIVE: The purpose of this study was to investigate replacing unenhanced and arterial single-energy CT acquisitions after endovascular aneurysm repair with one dual-energy CT arterial acquisition. SUBJECTS AND METHODS: Thirty patients underwent arterial dual-energy CT (80 and 140 kVp) and venous single-energy CT (120 kVp) after endovascular aneurysm repair, and the radiation doses were compared with those of a standard triple-phase protocol. Both virtual unenhanced and arterial images were generated with dual-energy CT. Images were reviewed clinically for detection of endoleaks and evaluation of stent and calcium appearance. The aortic luminal attenuation on virtual unenhanced CT images was compared with that on previously acquired true unenhanced images. Virtual unenhanced, arterial, and venous images were compared for thrombus attenuation. Single-energy CT and dual-energy CT images were compared for noise. RESULTS: Replacement of two (unenhanced, arterial) of three single-energy CT acquisitions with one dual-energy CT acquisition resulted in 31% radiation dose savings. All images were clinically interpretable. Thoracic (32 +/- 2 vs 35 +/- 4 HU) and abdominal (30 +/- 3 vs 35 +/- 5 HU) aortic attenuation was similar on virtual unenhanced and true unenhanced images. Thrombus attenuation was similar on virtual unenhanced (32 +/- 6 HU), arterial phase (33 +/- 7 HU), and venous phase (34 +/- 6 HU) images. Decreased stent and calcium attenuation was observed at some locations on virtual unenhanced images. Noise in the thoracic (10 +/- 1 HU) and abdominal (12 +/- 2 HU) aorta was lower on virtual unenhanced images than on true unenhanced images (13 +/- 4 HU, 19 +/- 5 HU). Noise was comparable for dual-energy and single-energy CT (thorax, 16 +/- 2 vs 13 +/- 2 HU; abdomen, 21 +/- 3 vs 23 +/- 5 HU). CONCLUSION: Virtual unenhanced and arterial phase images derived from dual-energy CT can replace true unenhanced and arterial phase single-energy CT images in follow-up after endovascular aneurysm repair (except immediately after the procedure), providing comparable diagnostic information with substantial dose savings.

Three-dimensional volume-rendering computed tomography for measuring humeral version.

HYPOTHESIS: Humeral version is highly variable in human beings. Accurate assessment of humeral version may allow for more anatomic reconstruction at shoulder arthroplasty. Two-dimensional (2D) computed tomography (CT) has been used to measure humeral version but has limitations of poor interobserver reproducibility and strict dependence on arm positioning during image acquisition. This study evaluated a new technique, 3-dimensional (3D) volume rendering, for measuring humeral version. MATERIALS AND METHODS: Eight dried human humerus specimens were included in the study. Gold standard measurements of humeral version were obtained by use of metallic beads and fluoroscopy. The specimens were then scanned at CT in 2 different positions, 1 neutral to the table and 1 angled at 20 degrees . The image data sets were used to measure humeral version in each bone with both the standard 2D technique and the new 3D technique. Measurements were performed by 3 readers at 2 different time points. Readers were blinded to the gold standard results and each others' measurements. RESULTS: For all readers, 3D measurements averaged within 4.3 degrees of the gold standard. For 2 of the 3 readers, 3D measurements were more accurate than 2D measurements. For all 3 readers, intraobserver variability was better with the 3D technique. For all reader pairs, interobserver variability was better with the 3D technique. CONCLUSIONS: This study shows a 3D volume-rendering CT technique to measure humeral version accurately and consistently that is independent of patient positioning.

Rheumatoid arthritis: evaluation with contrast-enhanced CT with digital bone masking.

The purpose of this HIPAA-compliant study was to prospectively evaluate the feasibility of contrast material-enhanced computed tomography (CT) with digital bone masking for the evaluation of synovitis and tenosynovitis in patients with rheumatoid arthritis. Four patients with rheumatoid arthritis and findings at magnetic resonance (MR) imaging were evaluated after informed consent for this institutional review board-approved study was obtained. To improve the conspicuity of synovial enhancement, postcontrast CT was performed with a relatively low kilovoltage and high iodine concentration and precontrast images were used as a subtraction mask to eliminate high-attenuation cortical bone contours. Moderate to high agreement between CT and MR imaging findings for synovitis and tenosynovitis was demonstrated, which suggests that this technique may be an acceptable alternative to MR imaging in the evaluation of rheumatoid arthritis.

The effect of misclassification in screening trials: a simulation study.

BACKGROUND: Misclassification of study endpoints in randomized clinical trials of screening tests has been well documented, yet its effect on study power, type I error rate, and risk ratio estimate have not been studied in depth. METHODS: We constructed a Markov model to depict the natural history of disease and the effect of screening on it. Using this model we simulated subjects in a two-arm RCT. We varied the type and amount of misclassification, and studied the effect on two endpoints--disease-specific mortality and the incidence of disease-specific symptoms. RESULTS: Failure to identify disease-specific events in a RCT of screening has a small effect on the risk ratio estimate and study power. In contrast, the false identification of events as being attributable to the target disease greatly reduces study power. CONCLUSIONS: Investigators of RCTs of screening tests should carefully consider the potential for misclassification and the type of misclassification that their study is as risk for. Studies should be designed to minimize misclassification. The effect of misclassification on power should be considered in sample size calculations.

Clinical, imaging, and pathological characteristics of left ventricular thrombus: a comparison of contrast-enhanced magnetic resonance imaging, transthoracic echocardiography, and transesophageal echocardiography with surgical or pathological validation.

BACKGROUND: Left ventricular (LV) thrombus is a frequent and potentially dangerous complication of ischemic heart disease (IHD). We evaluated the clinical, imaging, and pathology characteristics of confirmed LV thrombus and compared the diagnostic value of contrast-enhanced magnetic resonance imaging (MRI) with transthoracic (TTE) and transesophageal echocardiography (TEE) for the diagnosis of LV thrombi. METHODS: Between November 1997 and December 2003, 361 patients with IHD had surgical and/or pathological confirmation of presence or absence of LV thrombus. Clinical information and preoperative imaging study reports were retrospectively reviewed regarding detection of thrombus. Comparisons were made between clinical and imaging characteristics of patients with and without confirmed thrombus. RESULTS: Left ventricular thrombus was present in 106 (29%) of 361 patients in this study. Patients with thrombus had a higher incidence of recent embolic events (6.1% vs 0.8%, P < .005). In 160 patients with all 3 imaging modalities performed within 30 days of surgical or pathological confirmation, contrast-enhanced MRI showed the highest sensitivity and specificity (88% +/- 9% and 99% +/- 2%, respectively) compared with TTE (23% +/- 12% and 96% +/- 3.6%, respectively) and TEE (40% +/- 14% and 96% +/- 3.6%, respectively) for thrombus detection. CONCLUSIONS: Left ventricular thrombus occurs frequently in patients with IHD and is associated with risk of systemic embolization. Contrast-enhanced MRI provided the highest sensitivity and specificity for LV thrombus when compared to TTE and TEE, and should be considered in the care of patients at high risk of LV thrombus formation.

Absence of coronary sinus tributaries in ischemic cardiomyopathy: An insight from multidetector computed tomography cardiac venographic study.

OBJECTIVE: Cardiac resynchronization therapy (CRT) is an important therapeutic strategy in heart failure. However, there is a high incidence of lead implantation failure and suboptimal response, particularly in ischemic cardiomyopathy. This failure rate may partly be secondary to lack of suitable coronary sinus branches for lead implantation. We sought to assess the presence of coronary sinus (CS) tributaries in patients with ischemic and non-ischemic cardiomyopathy. MATERIALS AND METHODS: Multidetector computed tomography (MDCT) was performed in 100 patients: 25 coronary artery bypass graft (CABG) patients with impaired left ventricular ejection fraction (LVEF), 25 CABG patients with preserved LVEF, 25 patients with non-ischemic cardiomyopathy, and 25 controls. The presence of the CS and its tributaries, including the posterior interventricular vein (PIV), posterolateral vein (PLV), left marginal vein (LMV), and the anterior interventricular vein (AIV) was assessed. RESULTS: The CS, PIV, and AIV were demonstrated in all patients, whereas presence of a PLV and LMV was identified in 68% and 48% of CABG patients with impaired LVEF, 96% and 68% of CABG patients with preserved LVEF, 92% and 80% of patients with non-ischemic cardiomyopathy, and 100% and 80% of controls (p = 0.001 and 0.046 for PLV and LMV, respectively). CONCLUSIONS: This is the first report to demonstrate that the posterolateral vein and left middle vein, branches of the coronary sinus, are detectable in a significantly smaller number of CABG patients with impaired LVEF compared to controls, CABG with preserved LVEF, and non-ischemic cardiomyopathy. The absence of CS tributary veins in ischemic cardiomyopathy potentially hinders proper lead implantation and results in suboptimal CRT response.

Extent of myocardial scarring on nonstress delayed-contrast-enhancement cardiac magnetic resonance imaging correlates directly with degrees of resting regional dysfunction in chronic ischemic heart disease.

BACKGROUND: Hyper-enhancement on delayed-enhancement magnetic resonance imaging (DE-MRI) is a marker of irreversible myocardial injury. Both reversible and irreversible ischemically injured regions of myocardium develop reductions in systolic function compared with unaffected regions. This study evaluated whether there is a relationship between myocardial hyper-enhancement from remote scarring on DE-MRI and the degree of myocardial circumferential shortening (%CS) as determined with dynamic MRI tissue tagging (TAG-MRI) in the setting of chronic ischemic heart disease (CIHD). METHODS: Thirty-five patients with CIHD and 8 control patients underwent nonstress, resting DE-MRI and TAG-MRI. A total of 168 CIHD and 96 control segments from the basal- and middle-thirds of the left ventricle (LV) were selected to achieve a balanced test set. With a 16-segment model, segmental myocardial scarring was graded on the basis of the amount of hyper-enhancement on DE-MRI. With TAG-MRI images, segmental %CS was calculated. RESULTS: Patients with CIHD had lower LV ejection fraction compared with the control patients (28% vs 67%). The %CS of normal segments was notably different from %CS of CIHD segments, regardless of the presence or absence of myocardial hyper-enhancement on DE-MRI. Among the CIHD segments, however, %CS correlated inversely with the amount of myocardial hyper-enhancement from scarring (P <.0001, r = -0.38). CONCLUSIONS: On cardiac MRI for CIHD, myocardial hyper-enhancement correlates inversely with %CS, supporting the direct relationship between the amount of remote myocardial scarring determined with nonstress DE-MRI and baseline resting functional impairment.

Persistent abnormal left ventricular systolic torsion in dilated cardiomyopathy after partial left ventriculectomy.

OBJECTIVE: Rotation of the left ventricular apex relative to the base, or left ventricular torsion, is related to myocardial contractility and structure and is a sensitive indicator of cardiac dysfunction. We have quantified left ventricular systolic rotation and torsion in patients with dilated cardiomyopathy before and after partial left ventriculectomy in an attempt to characterize the effects of this surgical procedure on ventricular ejection mechanics. METHODS: Magnetic resonance imaging with tissue tagging was performed before partial left ventriculectomy in 24 patients, 9 of whom underwent repeat imaging 3 months after surgery. Left ventricular rotation was quantified in each patient at three short-axis levels: apex, midventricle, and base. Torsion was defined as the difference between basal and apical rotation at any time. Results were subdivided for regional analysis at each level and related to cardiac function (ejection fraction, cardiac index, and velocity of circumferential fiber shortening). RESULTS: Before surgery, left ventricular rotation was regionally heterogeneous and abnormal in magnitude and pattern, and increased end-systolic torsion was associated with better cardiac function. After surgery, clinical indices of cardiac function showed improvement; however, rotation magnitude was unchanged at the apex and reduced at the base and midventricle, particularly in the anterior wall and septum. CONCLUSIONS: The pattern and magnitude of ventricular rotation were impaired by dilated cardiomyopathy. Left ventricular rotation and torsion were further diminished after partial left ventriculectomy, indicating that improvement in clinical indices of cardiac function was not reflective of an improvement in this measure of myocardial mechanics.

Acute dissection of the descending aorta: noncommunicating versus communicating forms.

BACKGROUND: Noncommunicating dissecting intramural hematoma is an aortic dissection variant, characterized by absent flow within the false lumen. Noncommunicating dissecting intramural hematoma is thought to be more stable than communicating dissection when beginning in the descending aorta. This study assessed clinical characteristics, anatomic characteristics, and 1-year outcomes in acute descending noncommunicating dissecting intramural hematoma versus communicating dissection. METHODS: Retrospective database review identified patients who underwent magnetic resonance or computed tomography imaging revealing acute descending noncommunicating dissecting intramural hematoma or communicating dissection. Comparisons of clinical and anatomic characteristics and 1-year outcomes were performed. RESULTS: Twenty-four noncommunicating dissecting intramural hematoma and 36 communicating dissection cases were identified. Patients with noncommunicating dissecting intramural hematoma were older (68.5 +/- 8.8 versus 61.8 +/- 11.6 years; p < 0.05). Although noncommunicating dissecting intramural hematoma often showed abdominal aorta extension (50%), the infrarenal level was spared. Communicating dissection characteristically extended beyond the diaphragm (89%), including into the infrarenal aorta (28%). There was no significant difference in rates of adverse clinical events for noncommunicating dissecting intramural hematoma versus communicating dissection (13% versus 30%; 0.10 > p > 0.05). By follow-up imaging (87% of population), aortic deterioration was more frequent in noncommunicating dissecting intramural hematoma versus communicating dissection cases (60% versus 15%; p < 0.005). CONCLUSIONS: Acute descending noncommunicating dissecting intramural hematoma and communicating dissection represent two variants, with differing clinical and anatomic characteristics, but comparable levels of 1-year morbidity.

Noninvasive assessment of cardiac mechanics and clinical outcome after partial left ventriculectomy.

BACKGROUND: Partial left ventriculectomy (PLV) was developed as a therapy for end-stage heart failure, but results were variable with few a priori predictors of outcome. Little is known about its effects on myocardial mechanics and their relation to clinical outcome. METHODS: Twenty-four dilated cardiomyopathy patients underwent cardiac magnetic resonance imaging (MRI) before PLV, and 3 and 12 months after surgery. Left ventricular (LV) circumferential shortening and wall stress were computed at three short-axis levels. Exploratory outcome analysis grouped patients according to the timing of adverse cardiac events postsurgery. RESULTS: LV mass and volume were decreased at each postsurgical time point (all p < 0.01). At 3 months, regional wall stress was reduced at all short-axis levels; but by 12 months stress was reduced from baseline only at the apex. Circumferential shortening was increased significantly at both postsurgical time points at each level. On average, septal shortening was negative (stretching) before surgery, but increased significantly, and was positive, postsurgery. Exploratory outcome analysis found that negative values of basal septum circumferential shortening before surgery increased the probability of event-free survival beyond 6 months. CONCLUSIONS: Regional heterogeneity of LV myocardial function, associated with dilated cardiomyopathy, was diminished after PLV but was also related to patient outcome. MRI with tissue tagging is useful for assessing the efficacy of surgical therapies for congestive heart failure.

Non-invasive assessment of plaque morphology and remodeling in mildly stenotic coronary segments: comparison of 16-slice computed tomography and intravascular ultrasound.

BACKGROUND: Non-invasive identification and characterization of mildly stenotic atherosclerotic lesions is an increasingly important focus of coronary imaging. DESIGN: We examined the accuracy of multi (16)-slice computed tomography (MSCT) for imaging of these lesions in comparison with intravascular ultrasound (IVUS). MATERIALS: Mildly stenotic segments of the left coronary artery were identified by coronary angiography and analyzed using IVUS and contrast-enhanced MSCT. Independent reviewers evaluated the accuracy of MSCT for presence, composition and distribution of atherosclerotic plaque and remodeling response in comparison to IVUS using receiver operating characteristic (ROC) data analysis. RESULTS: Of 46 segments in 14 patients, diagnostic characterization by MSCT was possible in 37 (80.4%) segments. In these segments the accuracy of MSCT for identifying plaque presence, calcification, distribution and positive remodeling was consistently greater than 0.90 (reader 1) and 0.87 (reader 2). CONCLUSION: State-of-the-art MSCT can accurately identify mildly stenotic coronary atherosclerosis and provide an assessment of morphology and remodeling response.

Confidence bounds when the estimated ROC area is 1.01.

RATIONALE AND OBJECTIVES: In studies with small samples, the authors often encounter data sets in which the estimated area under the receiver operating characteristic (ROC) curve is 1.0. In such cases, neither asymptotic nor resampling methods provide a means of estimating the standard error or constructing a lower confidence bound. The purpose of this study was to develop tables for determining the approximate 95% lower confidence bound when the estimated ROC area is 1.0. MATERIALS AND METHODS: Using Monte Carlo simulation, the authors generated 10,000 data sets for each specification of sample sizes, ROC curve shape, and data format (continuous and ordinal scale). For each of these combinations the authors determined the 95% lower confidence bound. RESULTS: When the estimated ROC area is 1.0, the 95% lower confidence bounds differ dramatically depending on the shape of the ROC curve and on whether the test results are ordinal or continuous. Four tables of 95% lower confidence bounds are provided, along with guidelines for their use. CONCLUSION: Given the different shapes of ROC curves and the different formats in which ROC data are collected, it is not feasible to offer one simple method of constructing confidence bounds that works for all ROC curves. The tables provided in this article are useful for interpreting studies with estimated ROC areas of 1.0.

Texture analysis of lesions in breast ultrasound images.

We investigate the use of Haralick's texture features and posterior acoustic attenuation descriptors (PAAD) for the characterization of ultrasound (US) breast lesions. 71 lesions (24 cyst, 21 benign solid mass and 26 malignant solid masses) were manually segmented on two-dimensional breast US images. 28 Haralick's descriptors and two PAAD were evaluated on these segmented lesions. Mean of Sum Average, Range of Sum Entropy and the second PAAD best discriminated cysts from noncysts. Range of Correlation and the second PAAD best discriminated solid malignant from benign lesions. Computerized analysis of breast US images can increase the specificity of breast sonography by providing a better characterization of solid lesions.

Utilizing pre-therapy clinical schema and initial CT changes to predict progression-free survival in patients with metastatic renal cell carcinoma on VEGF-targeted therapy: a preliminary analysis.

OBJECTIVE: Because of varying treatment effectiveness with vascular endothelial growth factor (VEGF)-targeted therapy in patients with metastatic renal cell carcinoma (RCC), the association of prognostic pre-therapy clinical schema, initial post-therapy computed tomography (CT) findings, and combination thereof in predicting progression-free survival (PFS) was investigated. A predictive biomarker that combines clinical risk factors and CT imaging features associated with initial response to therapy would be useful in stratifying patients into risk groups to guide therapy, in designing and interpreting results of clinical trials, in planning risk-directed therapy, and in patient counseling. Early identification of poor responders using an imaging biomarker may reduce drug-related toxicity and cost and allow for a therapeutic intervention before disease burden significantly advances. MATERIALS AND METHODS: For this institutional review board-approved HIPAA-compliant retrospective study, baseline data for 82 patients with metastatic RCC treated with sunitinib or sorafenib was obtained for risk stratification by Memorial Sloan Kettering Cancer Center (MSKCC) criteria and criteria by Heng et al. (J Clin Oncol 2009;27:5794-9), (described here as "VEGF prognostic factors criteria"). The initial post-therapy CT was evaluated by Response Assessment Criteria in Solid Tumors (RECIST), Choi criteria, and Morphology, Attenuation, Size, and Structure (MASS) criteria. Kaplan-Meier estimates of PFS (the reference standard) for each patient group and overall accuracy of each method and combined criteria were calculated. RESULTS: The MSKCC model, VEGF prognostic factors criteria, RECIST, MASS criteria, MSKCC + MASS criteria, and VEGF prognostic factors + MASS criteria each demonstrated significant differences in PFS among patient groups (P < 0.005 for each, Log-rank test). Stratification of patient groups by Choi criteria was not statistically significant with respect to PFS (P = 0.101). MSKCC + MASS criteria yielded the highest overall accuracy for identifying PFS ≥ 1 year (77%) and for identifying PFS < 1 year (77%). CONCLUSIONS: A combination of pre-therapy clinical risk factors and CT imaging response by MASS criteria more effectively predicted PFS in patients with metastatic RCC on VEGF-targeted therapy than any single method.