64 research outputs found
Contrast-enhanced computed tomography assessment of aortic stenosis
Objectives Non-contrast CT aortic valve calcium scoring ignores the contribution of valvular fibrosis in aortic stenosis. We assessed aortic valve calcific and non-calcific disease using contrast-enhanced CT. Methods This was a post hoc analysis of 164 patients (median age 71 (IQR 66-77) years, 78% male) with aortic stenosis (41 mild, 89 moderate, 34 severe; 7% bicuspid) who underwent echocardiography and contrast-enhanced CT as part of imaging studies. Calcific and non-calcific (fibrosis) valve tissue volumes were quantified and indexed to annulus area, using Hounsfield unit thresholds calibrated against blood pool radiodensity. The fibrocalcific ratio assessed the relative contributions of valve fibrosis and calcification. The fibrocalcific volume (sum of indexed non-calcific and calcific volumes) was compared with aortic valve peak velocity and, in a subgroup, histology and valve weight. Results Contrast-enhanced CT calcium volumes correlated with CT calcium score (r=0.80, p<0.001) and peak aortic jet velocity (r=0.55, p<0.001). The fibrocalcific ratio decreased with increasing aortic stenosis severity (mild: 1.29 (0.98-2.38), moderate: 0.87 (1.48-1.72), severe: 0.47 (0.33-0.78), p<0.001) while the fibrocalcific volume increased (mild: 109 (75-150), moderate: 191 (117-253), severe: 274 (213-344) mm 3 /cm 2). Fibrocalcific volume correlated with ex vivo valve weight (r=0.72, p<0.001). Compared with the Agatston score, fibrocalcific volume demonstrated a better correlation with peak aortic jet velocity (r=0.59 and r=0.67, respectively), particularly in females (r=0.38 and r=0.72, respectively). Conclusions Contrast-enhanced CT assessment of aortic valve calcific and non-calcific volumes correlates with aortic stenosis severity and may be preferable to non-contrast CT when fibrosis is a significant contributor to valve obstruction
Treatment strategies in primary vitreoretinal lymphoma: a 17-center European collaborative study.
IMPORTANCE: The best treatment option for primary vitreoretinal lymphoma (PVRL) without signs of central nervous system lymphoma (CNSL) involvement determined on magnetic resonance imaging or in cerebrospinal fluid is unknown.
OBJECTIVE: To evaluate the outcomes of treatment regimens used for PVRL in the prevention of subsequent CNSL.
DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort study was conducted at 17 referral ophthalmologic centers in Europe. We reviewed clinical, laboratory, and imaging data on 78 patients with PVRL who did not have CNSL on presentation between January 1, 1991, and December 31, 2012, with a focus on the incidence of CNS manifestations during the follow-up period.
INTERVENTIONS: The term extensive treatment was used for various combinations of systemic and intrathecal chemotherapy, whole-brain radiotherapy, and peripheral blood stem cell transplantation. Therapy to prevent CNSL included ocular radiotherapy and/or ocular chemotherapy (group A, 31 patients), extensive systemic treatment (group B,â21 patients), and a combination of ocular and extensive treatment (group C,â23 patients); 3 patients did not receive treatment. A total of 40 patients received systemic chemotherapy.
MAIN OUTCOMES AND MEASURES: Development of CNSL following the diagnosis of PVRL relative to the use or nonuse of systemic chemotherapy and other treatment regimens.
RESULTS: Overall, CNSL developed in 28 of 78 patients (36%) at a median follow-up of 49 months. Specifically, CNSL developed in 10 of 31 (32%) in group A, 9 of 21 (43%) in group B, and 9 of 23 (39%) in group C. The 5-year cumulative survival rate was lower in patients with CNSL (35% [95% CI, 50% to 86%]) than in patients without CNSL (68% [95% CI, 19% to 51%]; Pâ=â.003) and was similar among all treatment groups (Pâ=â.10). Adverse systemic effects occurred in 9 of 40 (23%) patients receiving systemic chemotherapy; the most common of these effects was acute renal failure.
CONCLUSIONS AND RELEVANCE: In the present series of patients with isolated PVRL, the use of systemic chemotherapy was not proven to prevent CNSL and was associated with more severe adverse effects compared with local treatment
Akt phosphorylation on Thr308 but not on Ser473 correlates with Akt protein kinase activity in human non-small cell lung cancer
Iterative reconstruction incorporating background correction improves quantification of [18F]-NaF PET/CT images of patients with abdominal aortic aneurysm
Background
A confounding issue in [18F]-NaF PET/CT imaging of abdominal aortic aneurysms (AAA) is the spill in contamination from the bone into the aneurysm. This study investigates and corrects for this spill in contamination using the background correction (BC) technique without the need to manually exclude the part of the AAA region close to the bone.
Methods
Seventy-two (72) datasets of patients with AAA were reconstructed with the standard ordered subset expectation maximization (OSEM) algorithm incorporating point spread function (PSF) modelling. The spill in effect in the aneurysm was investigated using two target regions of interest (ROIs): one covering the entire aneurysm (AAA), and the other covering the aneurysm but excluding the part close to the bone (AAAexc). ROI analysis was performed by comparing the maximum SUV in the target ROI (SUVmax(T)), the corrected cSUVmax (SUVmax(T) â SUVmean(B)) and the target-to-blood ratio (TBRâ=âSUVmax(T)/SUVmean(B)) with respect to the mean SUV in the right atrium region.
Results
There is a statistically significant higher [18F]-NaF uptake in the aneurysm than normal aorta and this is not correlated with the aneurysm size. There is also a significant difference in aneurysm uptake for OSEM and OSEMâ+âPSF (but not OSEMâ+âPSFâ+âBC) when quantifying with AAA and AAAexc due to the spill in from the bone. This spill in effect depends on proximity of the aneurysms to the bone as close aneurysms suffer more from spill in than farther ones.
Conclusion
The background correction (OSEMâ+âPSFâ+âBC) technique provided more robust AAA quantitative assessments regardless of the AAA ROI delineation method, and thus it can be considered as an effective spill in correction method for [18F]-NaF AAA studies
Early Surgical Closure of the Ventricular Septal Defects; to Be Done or Not to Be Done? A Question to Be Answered
Cardiac surgery with extracorporeal circulation in 23 infant weighing 2500 g or less: short and intermediate term outcome
Objective and methods: From September 1990 to February 1997, 23 consecutive critically ill infants (12 males, 11 females) weighing 2500 g or less underwent cardiac surgery necessitating extracorporeal circulation (ECC). A retrospective study was carried out to evaluate short- and intermediate-term outcome. Mean weight at operation was 2265 g (range 1750- 2500 g). Mean age at operation was 24 days. The indications for surgery were transposition of the great arteries (TGA; 7), ventricular septal defect (VSD; 4), aortic stenosis (AS; 3), univentricular heart (UVH; 2), tetralogy of Fallot (TOF; 2), interrupted aortic arch (IAA; 2), atrial septal defect (ASD; 1), atrioventicular septal defect (AVSD; 1) and total abnormal pulmonary venous return (TAPVR; 1). All patients were in NYHA class IV; 17 patients (74%) were intubated pre-operatively. Results: The mean aortic cross-clamping time was 40 min. Twelve patients required deep hypothermia (<20°C) with total circulatory arrest (mean duration 19 min). All patients were successfully weaned from extracorporeal circulation (ECC). Five patients left the operating room with an open sternum (mean duration before closure: 3.5 days). Mean duration of artificial ventilation was 10.6 days; of inotropic support 6.7 days and of intensive care stay 17.8 days. Severe complications were observed in 19 patients (83%): cardiac failure requiring high inotropic support (13), sepsis (7), and acute renal insufficiency (5). One patient needed a ventricular assist device. Five patients (22%) died in the intensive care unit (ICU): 2 AS with fibroelastosis, 2 IAA with VSD, and 1 UVH with pulmonary atresia. At discharge from the ICU, 7 patients were receiving no treatment. Mean duration of follow-up was 32 months (range 2-80 months). We had 2 reoperations: 1 for right ventricular outflow tract obstruction 1 year after a switch operation and 1 for mitral valve replacement 1 year after total abnormal pulmonary venous return repair (death 30 days post mitral valve replacement). Survival at I year was 73%. At the last clinical examination 16 patients were in NYHA class I. Conclusion: Despite the severity of pre-operative cardiac disease, early surgical repair with ECC in infants weighing 2500 g or less is feasible with tolerable mortality yet with significant early morbidity.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
High-Sensitivity Cardiac Troponin I and the Diagnosis of Coronary Artery Disease in Patients with Suspected Angina Pectoris
Background: High-sensitivity assays can quantify cardiac troponin I concentrations in nearly all individuals. We determined whether cardiac troponin can improve our estimation of the pre-test probability for obstructive coronary artery disease in patients with suspected stable angina. Methods: In a pre-specified sub-study of the Scottish COmputed Tomography of the Heart (SCOT-HEART) trial, plasma cardiac troponin I was measured using a high-sensitivity single molecule counting assay (Singulex) in 943 adults with suspected stable angina who had undergone coronary computed tomography angiography. Rates of obstructive coronary artery disease (diameter stenosis â„50% in â„1 major epicardial vessel) were compared with the pre-test probability determined by the European Society of Cardiology (ESC) Coronary Artery Disease Consortium risk model with and without cardiac troponin concentrations. Results: Higher cardiac troponin concentrations were associated with obstructive coronary artery disease with a 5-fold increase across quintiles (9 to 48%, p < 0.001) independent of known cardiovascular risk factors (odds ratio [OR] 1.35 [95% confidence interval (CI) 1.25-1.46] per doubling of troponin). Cardiac troponin concentrations improved the discrimination of the ESC model for identifying obstructive coronary artery disease (c-statistic 0.785 to 0.800, p < 0.003) and improved classification into ESC-recommended categories of clinical risk (net reclassification improvement 0.143 [95% CI, 0.093-0.193]). Conclusions: High-sensitivity cardiac troponin I concentration is an independent predictor of obstructive coronary artery disease in patients with suspected stable angina. Use of this test may improve the selection of patients for further investigation and treatment
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