Ahmet Yalcin

Diagnostic performance of diffusion-weighted MRI in the detection of nonpalpable undescended testes: comparison with conventional MRI and surgical findings.

OBJECTIVE The aim of this feasibility study was to evaluate the role of diffusion-weighted MRI in the evaluation of nonpalpable undescended testes. MATERIALS AND METHODS Thirty-six boys with undescended testes underwent preoperative abdominal and pelvic MRI to identify the location of the testes. MRI included free-breathing diffusion-weighted imaging (DWI) with b values of 50, 400, and 800 s/mm(2), a T1-weighted turbo spin-echo sequence, and a T2-weighted fat-suppressed turbo spin-echo sequence. After laparoscopic examinations, two observers independently reviewed the preoperative images. The DW images alone were reviewed first, followed by the conventional MR images alone and the conventional MR and the DW images together. The laparoscopic and MRI findings were compared. Sensitivity, specificity, and accuracy in the identification of nonpalpable undescended testes were calculated for DWI, conventional MRI, and the combination of DWI and conventional MRI. RESULTS The combination of DWI and conventional MRI was the most sensitive and most accurate technique. Observer 1 found 31 undescended testes, and observer 2, 30 testes with this technique. Sensitivity was 0.91 and 0.88 for observers 1 and 2, and accuracy was 0.92 and 0.86. With DWI alone, observer 1 located 30 testes, and observer 2, 28 testes (sensitivity, 0.88 and 0.82; accuracy, 0.86 and 0.81). Using conventional MRI alone, both observers located 29 testes (sensitivity, 0.85; accuracy, 0.86 and 0.84). The accuracy of locating testes was superior with the combination of DWI and conventional MRI for both observers (accuracy, 0.92 and 0.86). An intraabdominal atrophic testis managed by laparoscopic orchiectomy was found by neither observer with DWI or with conventional MRI. CONCLUSION Use of DWI with a high b value yields information that complements conventional MRI findings, improving identification and location of nonpalpable undescended testes. We recommend the use of conventional MRI in addition to DWI to increase the preoperative sensitivity and accuracy of identifying and locating nonpalpable testes.

Comparison of peritoneal tumor imaging using conventional MR imaging and diffusion-weighted MR imaging with different b values

PURPOSE The aim of this study was to evaluate the utility of DW MRI with two different b values in identifying peritoneal tumors in oncology patients. MATERIALS AND METHODS Nineteen patients with known malignancy underwent abdominal and pelvic MRI before surgery. MRI included free-breathing DWI with b values of 400 and 800 s/mm2, T1-weighted fat-suppressed spoiled gradient-echo, T2-weighted fat-saturated turbo spin-echo, and 5-min delayed gadolinium-enhanced imaging. Two observers reviewed images for peritoneal tumors at ten anatomic sites within consensus. The results of laparatomy and histopathological evaluation were compared with MRI results. Sensitivity, specificity, and accuracy of identifying peritoneal metastases were calculated for conventional MRI, combined DWI with a b value of 400 s/mm2 and conventional MRI, and combined DWI with a b value of 800 s/mm2 and conventional MRI by consensus of two observers. RESULTS One-hundred and twenty-five peritoneal metastasis sites were confirmed by surgical and histopathological findings. Conventional MRI alone identified 72 peritoneal metastases (sensitivity, 0.58; specificity, 0.87; accuracy, 0.67). Combined DWI with a b value of 400 s/mm2 and conventional MRI revealed 106 peritoneal metastases (sensitivity, 0.85; specificity, 0.88; accuracy, 0.85). Finally, combined DWI with a b value of 800 s/mm2 and conventional MRI revealed 103 peritoneal metastases (sensitivity, 0.83; specificity, 0.94; accuracy, 0.86). CONCLUSION DWI with a high b value provides complementary information that can improve the detection of peritoneal tumors when combined with conventional MRI. We recommend combined MRI and DWI with a high b value for increasing the sensitivity and accuracy of the preoperative detection of peritoneal tumors.

Diagnostic performance of diffusion-weighted MR imaging in detecting acute appendicitis in children: Comparison with conventional MRI and surgical findings

To determine the value of diffusion‐weighted MRI for the diagnosis of acute appendicitis in children.

Clinical situations in which coronary CT angiography confers superior diagnostic information compared with coronary angiography

In this review, we aimed to outline the clinical and pathological conditions for which multidetector computed tomography coronary angiography (MDCT-CA) should be the preferred method because of its advantages over conventional coronary angiography (CCA). A consistent body of literature suggests that MDCT-CA is more than just complementary to CCA and that it provides more valuable diagnostic information in certain clinical situations, such as complex coronary artery variations, aorto-ostial lesions, follow-up of bypass grafts, myocardial bridging, coronary artery fistulas, aortic and coronary artery dissections, and cases in which the coronary ostia cannot be cannulated by a catheter because of massive atherosclerosis or extremely tortuous vascular structures.

High Sensitive CRP Level Is Associated With Intermediate and High Syntax Score in Patients With Acute Coronary Syndrome.

High sensitive C-reactive protein (hs-CRP) levels are associated with short- and long-term mortality in patients with acute coronary syndrome (ACS). We investigated whether baseline hs-CRP levels are associated with burden of coronary atherosclerosis assessed by SYNTAX score (SXScore).We enrolled 321 patients with ACS who underwent coronary angiography. The patients were divided into tertiles according to the SXScore: low SXScore (≤ 22), and intermediate-high SXScore (≥ 23).Subjects in the intermediate-high SXScore tertile had higher serum hs-CRP levels compare to low SXScore tertile patients (7.7 ± 3.4 mg/L versus 4.9 ± 2.5 mg/L, P < 0.001). The mean age of patients and prevalance of diabetes in the intermediate-high SXScore tertile were significantly higher than in the low SXScore tertile (63 ± 13 versus 58 ± 12 years P = 0.001 for age, P = 0.007 for diabetes). Multivariate logistic regression analysis showed that the strongest predictors of high SXScore were increased serum hs-CRP levels (OR: 1.14) together with multivessel disease (OR: 0.23), left ventricular ejection fraction (LVEF) (OR: 0.90), and troponin levels (OR: 1.12).Serum hs-CRP levels on admission in patients with ACS could predict the severity and complexity of coronary atherosclerosis together with multivessel disease, LVEF, and troponin levels. Thus, increased serum levels of hs-CRP were one of the strong predictors of high SXScore in ACS patients.

Does obesity limit the sonographic diagnosis of appendicitis in children

The purpose of this study is to evaluate whether obesity has a negative impact on the ultrasound (US) visualization of the appendix in children clinically diagnosed with appendicitis.

Association Between Contrast Media Volume-Glomerular Filtration Rate Ratio and Contrast-Induced Acute Kidney Injury After Primary Percutaneous Coronary Intervention.

We hypothesized that contrast media volume–estimated glomerular filtration rate (CV–e-GFR) ratio may be a predictor of contrast media-induced acute kidney injury (CI-AKI). We investigated the associations between CV–e-GFR ratio and CI-AKI in 597 patients undergoing primary percutaneous coronary intervention (pPCI). An absolute ≥0.3 mg/dL increase in serum creatinine compared with baseline levels within 48 hours after the procedure was considered as CI-AKI; 78 (13.1%) of the 597 patients experienced CI-AKI. The amount of contrast during procedure was higher in the CI-AKI group than in those without CI-AKI (153 vs 135 mL, P = .003). The CV–e-GFR ratio was significantly higher in patients with CI-AKI than without (2.3 vs 1.5, P < .001). In multivariate analysis, independent predictors of CI-AKI were low left ventricular ejection fraction (P = .018, odds ratio [OR] = 0.966), e-GFR <60 mL/min (P = .012, OR = 2.558), and CV–e-GFR >2 (P < .001, OR = 5.917). In conclusion, CV–e-GFR ratio is significantly associated with CI-AKI after pPCI.

Hypertension as a Risk Factor for Aspirin and Clopidogrel Resistance in Patients With Stable Coronary Artery Disease

Background: Platelets play an important role in the pathogenesis of coronary artery disease (CAD). The importance of dual antiplatelet therapy to prevent recurrent ischemic events in patients who have acute coronary syndrome and who will undergo percutaneous coronary intervention (PCI) is well known and widely accepted as a gold standard. However, despite this apparently effective therapy, incidence of adverse ischemic events could not be decreased enough. Resistance to aspirin/clopidogrel is an important risk factor for adverse ischemic clinical events. Up-to-date studies revealed many risk factors for antiplatelet resistance, one of which is hypertension (HT). Currently, there is no sufficient number of studies evaluating the association between HT and antiplatelet resistance, which is the aim of this study. Methods: We enrolled 145 consecutive patients (19 female [13.1%], 126 male [86.9%], mean age 55 ± 10) with stable CAD receiving regular antiplatelet therapy composed of 100 mg/d aspirin and 75 mg/d clopidogrel. All patients had been implanted nondrug-eluting coronary stent and/or stents at least 1 month ago. The HT was diagnosed by 24-hour blood pressure (BP) monitoring. Clopidogrel and aspirin resistance was measured by impedance aggregometry method. Results: We included 49 patients with HT and 96 nonhypertensive patients with stable CAD. Aspirin resistance was detected in 22 (16.4%) of 134 patients who received aspirin. Clopidogrel resistance was detected in 55 (37.9%) of 145 patients who received clopidogrel. Prevalance of aspirin and clopidogrel resistance was significantly higher in the hypertensive group than in the nonhypertensive group (P = .030 and P = .007, respectively). Correlation analysis revealed weak but significantly positive correlation between clopidogrel resistance and serum uric acid levels, mean platelet volume, platelet count, and 24-hour mean systolic BP (r = −.180, P = .030; r = .189, P = .016; r = .226, P = .006; and r = .200, P = .016, respectively). Conclusion: We demonstrated higher incidence of antiplatelet resistance in patients with HT. Upon this finding, which is emerged from an actual group of patients with HT, cardioprotective effect of antiplatelet therapy in patients with HT should be argued.

The Relationship Between Gamma-Glutamyl Transferase Levels and Coronary Plaque Burdens and Plaque Structures in Young Adults With Coronary Atherosclerosis

Elevated gamma‐glutamyl transferase (GGT) levels have been demonstrated to be associated with poor prognoses in patients with coronary artery disease. Coronary computed tomography angiography (CCTA) is a noninvasive imaging modality that may differentiate the structure of coronary plaques. Elevated plaque burdens and noncalcified plaques, detected by CCTA, are important predictors of atherosclerosis in young adults.

Ultrasound-guided shoulder MR arthrography: comparison of rotator interval and posterior approach

PURPOSE The purpose of this study was to prospectively evaluate the two different ultrasound-guided injection techniques for magnetic resonance (MR) arthrography of the shoulder. METHODS AND MATERIALS This study included 100 patients [50 rotator interval group (n=50) vs. 50 posterior approach group (n=50)]. All procedures were performed by the same radiologist. The two injection techniques were compared. The discomfort during and after arthrography was evaluated. Extraarticular contrast media extravasation was graded according to the MRI findings. The number of injection attempts, effect of contrast media extravasation rate on diagnostic quality and procedure times were recorded. RESULTS There were no significant difference between the posterior and rotator interval puncture groups with regard to pain (P=.915), procedure times (P=.401) or attempt scores (P=.182). There were significantly more contrast media extravasations with rotator interval approach than posterior approach (P<.05). CONCLUSION Both techniques were successful and well tolerated by patients. Posterior injection technique provided a more effective route with decreased extravasation rate and easier approach compared to the rotator interval approach.