Application of Iterative Metal Artifact Reduction Algorithm to CT Urography for Patients With Hip Prostheses.

OBJECTIVE. The purpose of this study is to retrospectively assess the impact of iterative metal artifact reduction (IMAR) with iterative reconstruction (IR) on the image quality and diagnostic performance of CT urography in the evaluation of patients with hip prostheses, compared with IR alone. MATERIALS AND METHODS. CT urography examinations that were reconstructed using IR with and without IMAR were analyzed for 57 patients (29 women and 28 men; mean age, 74 years [range, 22-94 years]) with hip prostheses (40 unilateral and 17 bilateral). For quantitative analysis, image noise within the bladder was measured. Two radiologists (radiologist 1 [RAD1] and radiologist 2 [RAD2]) qualitatively evaluated the images using both a 5-point scale to assess the degree of visualization of artifacts and a 6-point scale to determine diagnostic confidence in visualization of the bladder, ureters, prostate or uterus, pelvic calcifications, and genitourinary abnormalities involving the bladder, distal ureters, prostate, uterus, and ovaries. RESULTS. The combination of IMAR and an IR technique provided improvement in quantitative and qualitative measurements (p < 0.05). Forty-three genitourinary abnormalities were detected in 29 patients. Quantitative and qualitative comparisons of scans obtained with and without the use of IMAR, respectively, revealed image noise of 99.6 versus 173.3 HU and the following radiologist scores: for improvement of artifacts, 3.2 versus 1.6 (for RAD1) and 3.1 versus 1.6 (for RAD2); for visualization of the bladder, 3.6 versus 1.5 (RAD1) and 3.8 versus 1.6 (RAD2); visualization of the ureters, 3.8 versus 1.6 (RAD1) and 3.9 versus 1.7 (RAD2); visualization of the uterus, 4.3 versus 2.8 (RAD1) and 4.3 versus 2.6 (RAD2); visualization of the prostate, 4.5 versus 2.3 (RAD1) and 4.5 versus 2.2 (RAD2); diagnostic confidence for calcifications, 4.7 versus 3.5 (RAD1) and 4.7 versus 3.3 (RAD2); and diagnostic confidence for genitourinary abnormalities, 5.0 versus 3.2 (RAD1) and 4.8 versus 2.9 (RAD2), respectively. CONCLUSION. The addition of IMAR to IR led to statistically significant improvement in the retrospective diagnostic performance and image quality of CT urography for patients with hip prostheses, compared with IR alone.

Comparison of Tin Filter-Based Spectral Shaping CT and Low-Dose Protocol for Detection of Urinary Calculi.

OBJECTIVE: The purpose of this study was to assess the performance of tin filter-based spectral shaping CT compared with routine low-dose CT for detection of urolithiasis. MATERIALS AND METHODS: Unenhanced third-generation dual-source CT scans of 129 consecutively registered patients were retrospectively reviewed: 43 patients underwent CT for detection of renal stones with tin filtration (Sn150 kV); 43 patients underwent a routine low-dose CT protocol at 100 kV; and 43 patients underwent a routine CT protocol with automated tube potential selection (110-120 kV). Image quality was evaluated subjectively and objectively. Volume CT dose index (CTDIvol) and size-specific dose estimate (SSDE) were recorded. To prospectively compare the performances of the spectral shaping protocol (Sn150 kV) with the standard (120 kV) and routine low-dose (100 kV) protocols, a phantom (sheep kidneys) containing stones were also scanned with each protocol and evaluated by two radiologists. RESULTS: CT with tin filtration resulted in 28% and 66% reduction in CTDIvol compared with CT performed with routine low-dose and standard-dose protocols (p < 0.05). Accordingly, it also led to 24% and 55% reduction in SSDE compared with the low-dose and standard protocols (p < 0.05). Subjective image quality and signal-to-noise ratio were similar between the tin filtration and the routine low-dose groups (p > 0.05). The objective image noise was similar in the three groups (p > 0.05). The phantom study showed no difference in detection of renal stones between the three tube potential settings. CONCLUSION: Using spectral shaping with tin filtration can substantially reduce radiation dose compared with routine standard- and low-dose abdominal CT for urinary stone disease.

Integration of fully automated computer-aided pulmonary nodule detection into CT pulmonary angiography studies in the emergency department: effect on workflow and diagnostic accuracy.

PURPOSE: To assess the feasibility of implementing fully automated computer-aided diagnosis (CAD) for detection of pulmonary nodules on CT pulmonary angiography (CTPA) studies in emergency setting. MATERIALS AND METHODS: CTPA of 48 emergency patients was retrospectively reviewed. Fully automated CAD nodule detection was performed at the scanner and results were automatically submitted to PACS. A third-year radiology resident (RAD1) and a cardiothoracic radiologist with 6 years' experience (RAD2) reviewed the scans independently to detect pulmonary nodules in two different sessions 8 weeks apart: session 1, CAD was reviewed first and then all images were reviewed; session 2, CAD was reviewed last after all images were reviewed. Time spent by RAD to evaluate image sets was measured for each case. Fisher's exact test and t test were used. RESULTS: There were 17 male and 31 female patients with mean ± SD age of 48.7 ± 16.4 years. Using CAD at the beginning was associated with lower average reading time for both readers. However, difference in reading time did not reach statistical significance for RAD1 (RAD1 94.6 s vs. 102.7 s, P > 0.05; RAD2 61.1 s vs. 76.5 s, P < 0.05). Using CAD at the end significantly increased rate of RAD1 and RAD2 nodule detection by 34% (2.52 vs. 2.12 nodule/scan, P < 0.05) and 27% (2.23 vs. 1.81 nodule/scan, P < 0.05), respectively. CONCLUSION: Routine utilization of CAD in emergency setting is feasible and can improve detection rate of pulmonary nodules significantly. Different methods of incorporating CAD in detecting pulmonary nodules can improve both the rate of detection and interpretation speed.

Reactions to Both Nonionic Iodinated and Gadolinium-Based Contrast Media: Incidence and Clinical Characteristics.

OBJECTIVE: The objective or our study was to assess the incidence rate and clinical characteristics of allergiclike reactions in patients who received both nonionic iodinated contrast medium (ICM) and gadolinium-based contrast medium (GBCM). MATERIALS AND METHODS: Acute allergiclike reactions in patients who received both ICM and GBCM to nonionic ICM or GBCM injections during a 5-year period were analyzed. Allergy preparation was not administered when patients received a different type of contrast material. Acute allergiclike reactions to both ICM and GBCM were evaluated. RESULTS: Of 302,858 contrast injections (155,234 ICM and 147,624 GBCM) during a 5-year period, 1006 (752 ICM and 254 GBCM) acute allergiclike contrast reactions were reported. The overall rate of reaction to ICM was 0.48% (95% CI, 0.45-0.52%), and the overall rate of reaction to GBCM was 0.17% (95% CI, 0.15-0.19%). A total of 19,237 patients received at least one ICM injection and one GBCM injection, with a total of 56,310 injections (19,237 initial injections and 37,073 subsequent injections). Nine patients had reactions to both ICM and GBCM with the primary reaction rate of 9/19,237 (incidence rate, 0.047%; 95% CI, 0.044-0.050%), and the secondary reaction rate of 9/37,073 (incidence rate, 0.024%; 95% CI, 0.023-0.026%). All secondary reactions in patients who had a reaction to both ICM and GBCM were mild. None of the patients required medication for the treatment of the secondary reaction. CONCLUSION: An allergiclike reaction to both nonionic ICM and GBCM was an extremely rare event that presented as a mild acute reaction without significant clinical consequences despite the fact that an allergy preparation was not administered.

Dual-energy CT evaluation of gastrointestinal bleeding.

Gastrointestinal bleeding is a common cause for hospital admissions and is an important cause of morbidity and mortality. Although endoscopy is accepted as the standard initial diagnostic modality for the evaluation of gastrointestinal bleeding, multiphasic computed tomography (CT) imaging has become an alternative diagnostic tool. Dual-energy CT with post-processing techniques may have additional advantages over single-energy computed tomography in evaluation of gastrointestinal bleeding. In this article, we discuss the role of dual-energy CT in the evaluation of gastrointestinal bleeding with potential advantages over conventional CT and limitations.

Sex-specific incidence rates and risk factors of premature cardiovascular disease. A long term follow up of the Tehran Lipid and Glucose Study.

OBJECTIVES: To investigate the risk factors for premature cardiovascular disease (CVD) and to quantify their population attributable fractions (PAFs) among an Iranian population during a median follow-up of 12years. METHODS: A total of 2235 men and 3703 women, aged ≥30years, free of CVD at baseline were entered into the study. Premature CVD was defined as having a history of CVD events before the age of 55 and 65 for men and women, respectively. Multivariate Cox proportional hazard regression models were used to determine the risk factors associated with premature CVD events. RESULTS: During the study, incident rates of premature CVD were 4.8 and 3.9 per 1000 person years for men and women, respectively. Low HDL-C [Hazard ratio: 1.74, 95% confidence interval: 1.11-2.74], hypercholesterolemia [3.01: 2.02-4.49], current smoker [1.68: 1.12-2.51], family history of premature CVD [2.04: 1.36-3.07], hypertension [1.65: 0.97-2.81, P=0.06] and type 2 diabetes(T2D) [1.98: 1.16-3.40] were significant predictors among men; the corresponding PAFs were 32.7, 29.4, 19.4, 14.9, 8.7 and 7.9%, respectively. Among women, T2D [3.02: 2.08-4.39], hypercholesterolemia [1.65: 1.19-2.29], being overweight [1.79: 1.01-3.17], hypertension [1.54: 1.01-2.34], family history of premature CVD [1.65: 1.19-2.29], high physical activity [0.67: 0.46-0.96] and prediabetes [1.48: 1.00-2.18] were significant predictors; the corresponding PAFs were 25.4, 22.5, 18.5, 16.8, 11.4, -10.3 and 9.1%, respectively. CONCLUSIONS: Considering the high burden imposed on health system by cardio-metabolic risk factors, dietary, behavioral and pharmacological interventions are need to be initiated early to prevent premature CVD, taking into account the sex-related differences between risk factors.

Twelve-Year Cardiovascular and Mortality Risk in Relation to Smoking Habits in Type 2 Diabetic and Non-Diabetic Men: Tehran Lipid and Glucose Study.

INTRODUCTION: To examine the associations between smoking and cardiovascular disease (CVD) / coronary heart disease (CHD) and all-cause mortality events in men with and without type 2 diabetes (T2D) in a Middle Eastern cohort during a median follow-up of 12 years. METHODS: The study population included 2230 subjects aged ≥ 40 years, free from CVD, comprised of 367 participants with diabetes (21.2% current smokers) and 1863 without (27.3% current smokers). Multivariate Hazard ratios (HR) and 95% confidence intervals (CI) were calculated for smoking (considering different definitions) for those with and without diabetes. Potential confounding factors including age, body mass index, estimated Glomerular Filtration Rate, hypertension, hypercholesterolemia and educational level were entered in the multivariate analysis. RESULTS: In men with diabetes, the HR (95% CI) of comparing current and non-smokers was 1.25 (0.74-2.12) for incident CHD, 1.52 (0.96-2.40) for CVD and 2.10 (1.27-3.47) for mortality events; the corresponding values for men without diabetes were 1.65 (1.24-2.20), 1.70 (1.30-2.22) and 1.72 (1.14-2.58), respectively (all P values for interactions > 0.46). After pooling past smokers with current smokers, among diabetic individuals there was no significant risk for CVD [1.29 (0.89-1.86)] or mortality events [1.25 (0.81-1.92)]; however, among non-diabetic individuals the HRs of current/past smokers reached significant levels for CVD [1.53 (1.23-1.91)] but not for mortality outcomes (all P values for interactions > 0.51). CONCLUSIONS: The strength of the associations between smoking habits and incident CVD/CHD and mortality events from all causes did not differ significantly among diabetic and non-diabetic participants. Therefore, a comprehensive community-based smoking prevention program is important, given the increasing trend of smoking among the Iranian population regardless of diabetes status.

Change in fasting plasma glucose and incident type 2 diabetes mellitus: results from a prospective cohort study.

OBJECTIVE: To investigate the association between changes in fasting plasma glucose (FPG) values and incident type 2 diabetes (T2D) in a cohort of the Iranian population. DESIGN: Prospective cohort study. SETTING: This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS) to investigate the association between change in FPG between baseline examination (1999-2001) and the second visit (2002-2005) with incident T2D. PARTICIPANTS: A total of 3981 non-diabetic participants aged ≥20 years. OUTCOME MEASURE: T2D was defined if the participant was using antidiabetic drugs or if FPG was ≥7 mmol/L or if the 2 h post-challenge plasma glucose (2-hPCG) was ≥11.1 mmol/L. RESULTS: During a median follow-up of 6.17 years, after the second examination, 288 new cases of T2D were identified. In a multivariate Cox proportional hazard analysis using age as timescale, we presented a simple model including FPG change (HR 1.19, 95% CI 1.07 to 1.33) and baseline waist circumference (WC) (HR 1.004, 95% CI 1.001 to 1.008) with a discriminative power (C-index) of 72%. Furthermore, we showed that the highest quartile of FPG change enhanced the T2D risk to 1.65 (95% CI 1.2 to 2.27) compared with the lowest quartile (p for trend=0.004).The independent risk of FPG change resisted further adjustment with 2-hPCG change. Adding the 2-hPCG change only slightly increased the discriminative power of the model including FPG change and baseline value of WC (0.73% vs 0.72%). After the study population had been limited to those with normal fasting glucose/normal glucose tolerance, FPG change remained an independent predictor (HR 1.57, 95% CI 1.31 to 1.88). CONCLUSIONS: Two measurements of FPG obtained about 3 years apart can help to identify populations at risk of incident T2D independently of important traditional risk factors and their changes, including 2-hPCG change.

Successful surgical intervention in an unusual case of Aspergillus endocarditis with acute myeloid leukemia.

Endocarditis due to Aspergillus infection is a rare complication in patients with hematological malignancies. Here, we present a case of aspergillus endocarditis in a patient with acute myeloid leukemia (AML) successfully treated with antifungal therapy and surgical treatment. The patient was a 51 years old male, a known case of AML who was admitted to our medical center for evacuating his valvular vegetations and repairing his atrial septal defect. He underwent an open heart surgery to relinquish his thromboses and also received an antifungal regimen. The patient tolerated the procedure well and eight months after his surgery, the patient remains asymptomatic. Successful treatment of this severe case of aspergillus endocarditis justifies a multidisciplinary method to be as a safe and effective approach to manage these patients.

Risk factors affecting the survival rate in patients with symptomatic pericardial effusion undergoing surgical intervention.

OBJECTIVES: The optimal management and treatment of pericardial effusion are still controversial. There is limited data related to the risk factors affecting survival in these patients. The aim of this study was to determine the risk factors affecting the survival rate of patients with symptomatic pericardial effusion who underwent surgical interventions. METHODS: From 2004 to 2011, we retrospectively analysed 153 patients who underwent subxiphoid pericardial window as their surgical intervention to drain pericardial effusions at the National Research Institute of Tuberculosis and Lung diseases (NRITLD). To determine the effects of risk factors on survival rate, demographic data, clinical records, echocardiographic data, computed tomographic and cytopathological findings and also operative information of patients were recorded. Patients were followed annually until the last clinical follow-up (August 2011). To determine the prognostic factors affecting survival, both univariate analysis and multivariate Cox proportional hazards model were utilized. RESULTS: There were 89 men and 64 women with a mean age of 50.3 ± 15.5 years. The most prevalent symptom was dyspnoea. Concurrent malignancies were present in 66 patients. Lungs were the most prevalent primary site for malignancy. The median duration of follow-up was 15 (range 1-85 months). Six-month, 1-year and 18-month survival rates were 85.6, 61.4 and 36.6%, respectively. In a multivariate analysis, positive history of lung cancer (hazard ratio [HR] 2.894, 95% confidence interval [CI] 1.362-6.147, P = 0.006) or other organ cancers (HR 2.315, 95% CI 1.009-50311, P = 0.048), presence of a mass in the computed tomography (HR 1.985, 95% CI 1.100-3.581, P = 0.023), and echocardiographic findings compatible with tamponade (HR 1.745, 95% CI 1.048-2.90 P = 0.032) were the three independent predictors of postoperative death. CONCLUSIONS: In the surgical management of pericardial effusion, patients with underlying malignant disease, especially with lung cancer, patients with a detectable invasion of thorax in computed tomography and those with positive echocardiographic findings compatible with tamponade have a poor survival. Therefore, minimally invasive therapies could be considered as a more acceptable alternative for these high-risk patients.

First successful combined heart and kidney transplant in Iran: a case report.

Combined heart and kidney transplant has become an accepted therapy for patients with coexisting heart and kidney failure. This method, compared with single-organ transplant, has a better outcome. Here, we report the first successful combined heart and kidney transplant in Iran. The patient was a 36-year-old man with end-stage renal disease owing to IgA nephropathy, admitted to Masih Daneshvari Hospital in Tehran, Iran for progressive dyspnea and chest pain. In-patient evaluations revealed cardiomyopathy leading to end-stage heart failure. Owing to concurrent heart and kidney end-stage diseases, combined cardiorenal transplant was done. Eight months after his transplant, routine follow-ups have not shown any signs of acute rejection. He is now New York Heart Association functional class I. Both cardiac and renal functions are within normal ranges. Good outcome during follow-up for this case justifies simultaneous heart plus kidney transplants as an alternate treatment for patients with advanced disease of both organs.