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Sukru Mehmet Erturk

Publications and source records attributed to Sukru Mehmet Erturk.

14 recordsLinked to original sources
PubMed2006

PET imaging for evaluation of metastatic colorectal cancer of the liver.

Colorectal cancer is a major cause of cancer death in Western Europe and United States; the liver is the most common site for colorectal metastases. PET has an important role in the management of patients with colorectal liver metastases. It is an effective tool to detect hepatic metastases and to monitor the response to systemic and local therapy. The major impact of PET-CT over PET alone is the improvement in the certainty of lesion location. PET-CT has the unique advantage to combine functional and anatomic imaging in an integrated scanner; it allows a thoroughly evaluation of patients with colorectal liver metastases.

Aged↗
PubMed2006

Multiphasic contrast-enhanced multidetector-row CT of liver: contrast-enhancement theory and practical scan protocol with a combination of fixed injection duration and patients' body-weight-tailored dose of contrast material.

The introduction of multidetector-row CT (MDCT) has provided the abdominal radiologists with dramatic changes for the imaging of the liver. At just present, establishment of new and optimal injection protocol in multiphasic contrast-enhanced MDCT of the liver has been yearned because the difficulty and the importance to optimize the scan timing for each phase imaging have obviously increased because of the extremely rapid scan speed with MDCT scanners. Among technical factors employed in an injection protocol for multiphasic contrast-enhanced MDCT of the liver, to make an injection duration of contrast material fixed is the most important for the precise estimation of the scan timing for each phase imaging. With the fixed injection duration, the peak enhancement time of the aorta, portal vein, and liver constantly appear approximately 10, 20, and 30s after the any fixed injection durations (completion of injection of contrast material), respectively. Moreover, using a combination of the fixed injection duration and patients' body-weight-tailored dose of contrast material, similarity of time-density curves of each organ in shape and pattern can be achieved for individual patient with different body weight. In this issue, we will attempt to determine an ultimately optimal, but practical injection/scan protocol to successfully realize multiphasic contrast-enhanced MDCT of the liver based on the contrast-enhancement theory.

Body Weight↗
PubMed2006

CT features of hepatic venoocclusive disease and hepatic graft-versus-host disease in patients after hematopoietic stem cell transplantation.

OBJECTIVE: We conducted this study to evaluate whether CT scans could be used to differentiate hepatic venoocclusive disease from hepatic graft-versus-host disease in patients treated with hematopoietic stem cell transplantation. SUBJECTS AND METHODS: We retrospectively evaluated 18 patients (eight women, 10 men; mean age, 42.4 years) after hematopoietic stem cell transplantation with biopsy-proven hepatic venoocclusive disease (n = 5), hepatic graft-versus-host disease (n = 6), or both (n = 7). Two radiologists reviewed abdominal and pelvic CT scans for hepatomegaly (> 18 cm), splenomegaly (> 13 cm), size of main portal and right hepatic veins, presence of periportal edema, gallbladder wall edema, hydropic gallbladder, ascites, and small-bowel wall thickening. CT and histopathology findings were correlated using analysis of variance and Fisher-Free-man-Holton tests. RESULTS: Ascites and periportal edema were present in all five patients with venoocclusive disease, but of six patients with graft-versus-host disease, ascites was seen in two (p < 0.05) and periportal edema in only one (p < 0.05). Small-bowel wall thickening was encountered in five patients with graft-versus-host disease and in none with venoocclusive disease (p < 0.05). The right hepatic vein diameter in patients with venoocclusive disease (mean, 0.27 cm) was significantly smaller than the right hepatic vein diameter in patients with graft-versus-host disease (mean, 0.87 cm; p < 0.05). CONCLUSION: In patients treated with hematopoietic stem cell transplantation, CT findings of periportal edema, ascites, and a narrow right hepatic vein suggest venoocclusive disease rather than graft-versus-host disease. Small-bowel wall thickening suggests graft-versus-host disease.

Adult↗
PubMed2006

High-B-value diffusion-weighted MRI in colorectal cancer.

OBJECTIVE: The purpose of this article is to evaluate the usefulness of high-b-value diffusion-weighted MRI (DW-MRI) in the detection of colorectal adenocarcinoma. CONCLUSION: High-b-value DW-MRI allows detection of colorectal adenocarcinoma with a high sensitivity and specificity.

Adenocarcinoma↗
PubMed2006

MDCT of pancreatic adenocarcinoma: optimal imaging phases and multiplanar reformatted imaging.

OBJECTIVE: The objective of our study was to evaluate the individual contributions of arterial, pancreatic parenchymal, and portal venous phase (PVP) images and the utility of coronal and sagittal multiplanar reformatted (MPR) images in the assessment of pancreatic adenocarcinoma using triple-phase MDCT. MATERIALS AND METHODS: Thirty-one patients with and 35 patients without pancreatic adenocarcinoma underwent triple-phase MDCT. Three radiologists independently attempted to detect pancreatic adenocarcinoma and assess local extension using the MDCT images in five sessions. The first three sessions involved sets of images obtained in arterial phase, pancreatic parenchymal phase, and PVP separately and respectively. In the fourth session, a combination of axial images from all phases was evaluated. During the fifth session, radiologists had access to coronal and sagittal MPR images together with the axial images obtained in all phases. Results were compared with surgical findings using receiver operating characteristic (ROC) analysis and kappa statistics. RESULTS: Regarding tumor detection, the image set composed of coronal and sagittal MPR images and of axial images obtained in all phases had a significantly higher value for the area under the ROC curve (A(Z), 0.98 +/- 0.01) than the other image sets and yielded the highest sensitivity (93.5%). The sensitivity of the arterial phase image set (80.6%) was significantly lower than that of all other image sets. Whereas the image set composed of coronal and sagittal MPR images and axial images obtained in all phases yielded the highest kappa values for all local extension factors evaluated, the image set composed of only arterial phase images yielded the lowest kappa values for almost all of the factors. CONCLUSION: A combination of pancreatic parenchymal phase and PVP imaging is necessary and efficient for the assessment of pancreatic adenocarcinoma. The addition of coronal and sagittal MPR images increased the performance of MDCT, especially in the evaluation of local extension.

Adenocarcinoma↗
PubMed2006

Fine-needle aspiration biopsy of solid pancreatic masses: comparison of CT and endoscopic sonography guidance.

OBJECTIVE: Imaging-guided biopsies of solid pancreatic masses are performed with either CT or endoscopic sonography at our institution. We compared test characteristics of fine-needle aspiration biopsies guided using CT with those guided using endoscopic sonography and secondarily evaluated for an effect of mass size. MATERIALS AND METHODS: Of 70 solid pancreatic masses, 43 (mean size, 4.4 cm; range, 1.5-10.3 cm) underwent fine-needle (20- to 22-gauge) aspiration biopsy with CT guidance and 27 (mean size, 2.3 cm; range, 1.0-5.0 cm) underwent fine-needle (22-gauge) aspiration biopsy with endoscopic sonography guidance. The diagnostic rate, sensitivity, and negative predictive value (NPV) for each technique were compared using Fisher's exact test before and after stratifying masses by size as small (< or = 3 cm) or large (> 3 cm). RESULTS: The overall diagnostic rate, sensitivity, and NPV of fine-needle aspiration biopsies guided using CT (97.7%, 94.9%, and 60%, respectively) were not significantly different from those guided using endoscopic sonography (88.9%, 85%, and 57.1%, respectively). Among small masses, the diagnostic rate and sensitivity for biopsies guided using CT (100% and 100%, respectively) were not significantly different from those for biopsies guided using endoscopic sonography (90.9% and 93.8%, respectively). Among large masses, the diagnostic rate and sensitivity (96.6% and 92.3%, respectively) for biopsies guided using CT were not significantly different from those for biopsies guided using endoscopic sonography (83.3% and 50%, respectively). CONCLUSION: When biopsying solid pancreatic masses with fine needles, procedures guided with CT and those guided with endoscopic sonography have similar test characteristics regardless of mass size.

Adult↗
PubMed2005

State-of-the-art computed tomographic and magnetic resonance imaging of the gastrointestinal system.

Among the major innovations in radiology of the gastrointestinal (GI) system are the replacement of classic invasive diagnostic methods with noninvasive ones and the improvement in lesion characterization and staging of pancreatobiliary malignancies. Developments in imaging technology have led to many improvements in the field of diagnostic GI radiology. With its fast and thin-section scanning abilities, multidetector-row CT (MDCT) strengthens the place of CT as the most efficient tool to diagnose, characterize, and preoperatively stage pancreatic neoplasms. MR cholangiopancreatography has widely replaced endoscopic retrograde cholangiopancreatography in the diagnosis and staging of pancreatobiliary malignancies. MR imaging, using phased-array or endorectal coils, demonstrates local tumor invasion accurately in rectal cancers and thus allows an improved surgical planning. Virtual colonoscopy with MDCTs is an efficient screening method for colon cancer, and MDCT enterography is becoming the standard imaging technique for many small bowel disorders. The continuing developments in CT and MR technology will most probably further improve the accuracy of these and other imaging applications in the near future.

Gastrointestinal Diseases↗
PubMedDate not supplied

Pancreatic adenocarcinoma: MDCT versus MRI in the detection and assessment of locoregional extension.

PURPOSE: To compare dynamic-contrast enhanced multirow detector computed tomography (MDCT) including multiplanar reformatted images (MPR) and magnetic resonance imaging (MRI) including magnetic resonance cholangiopancreatography images for the detection and assessment of locoregional extension of pancreatic adenocarcinoma. MATERIALS AND METHODS: Twenty-four patients with and 21 patients without pancreatic adenocarcinoma underwent triple-phase MDCT and MRI. Three radiologists independently attempted to detect pancreatic adenocarcinoma and assess locoregional extension in 3 sessions. First session involved MDCT images. In the second session, radiologists had access to coronal and sagittal MPR images together with the axial images (MDCT + MPR). Third session involved MR images. Results were compared with surgical findings using receiver operating characteristic analysis and kappa statistics. RESULTS: Regarding tumor detection, MDCT + MPR had a significantly higher value for areas under the curve (0.96 +/- 0.02) at receiver operating characteristic analysis compared with those of MRI (0.90 +/- 0.03) and MDCT (0.85 +/- 0.04). MDCT + MPR had the highest mean sensitivity (96%), and MRI had the highest mean specificity (98%). For locoregional extension, MDCT + MPR showed the highest kappa values of the study for all factors evaluated (range, 0.63-0.86). CONCLUSIONS: In conclusion, multiphasic MDCT imaging with MPR images was superior to multiphasic MDCT imaging without MPR images and to comprehensive MRI employing 2-D sequences and magnetic resonance cholangiopancreatography for both the detection and assessment of locoregional extension of pancreatic adenocarcinomas. MRI might be used for further lesion characterization regarding its high specificity.

Adenocarcinoma↗
PubMedDate not supplied

Computed tomography features of nonalcoholic steatohepatitis with histopathologic correlation.

OBJECTIVE: This study was conducted to describe the computed tomography (CT) features of nonalcoholic steatohepatitis (NASH) and to evaluate if the CT features could be used to diagnose and stage NASH. METHODS: From 1994 until 2004, pathology records revealed 68 patients with NASH. Of these, 12 patients underwent CT scans before (n=6), on the same day as (n=3), or after (n=3) a liver biopsy. Using the same database, 9 patients with steatosis alone evaluated with a CT scan before (n=2), on the same day as (n=3), or after (n=4) the liver biopsy were selected as a control group. Two radiologists measured liver attenuation (compared with spleen) and assessed the pattern of steatosis, craniocaudal liver span, caudate-to-right lobe ratio, preportal space distance, and presence of porta hepatis lymph nodes and ascites. Biopsy specimens were assessed by a pathologist, and the degree of necroinflammatory activity, steatosis, and fibrosis was determined. Histopathologic and CT findings were compared between patients with NASH and patients with steatosis alone using the Mann-Whitney U test and Fisher exact test. RESULTS: In patients with NASH, the mean liver-to-spleen attenuation ratio was 0.66 (range: 0.1-1.1). Steatosis was diffuse (n=9), geographic or nonlobar (n=2), or diffuse with an area of focal sparing (n=1). The liver craniocaudal span varied from 17.5 to 25.5 cm (mean=21.4 cm), and hepatomegaly was present in 11 (91.7%) patients. The caudate-to-right-lobe ratio (mean=0.43) and preportal space (mean=4.5 mm) were normal in all cases. Porta hepatis lymph nodes were present in 7 (58.3%) patients; their mean dimensions were 16 mmx11 mm. Ascites was absent in all patients. On histopathology, the degree of necroinflammatory activity was mild (n=9), moderate (n=1), or severe (n=2). The degree of steatosis was 33% to 66% (n=5) or >67% (n=7). All but 3 patients had fibrosis; 6 had focal nonbridging fibrosis, 1 had multifocal nonbridging fibrosis, and 2 had bridging fibrosis. There was a significant correlation between the degree of steatosis on pathologic examination and the liver-to-spleen attenuation ratio on CT (P=0.048). The severity of inflammation and stage of fibrosis on pathologic examination did not correlate with the CT features. Among patients with steatosis alone, the mean liver-to-spleen attenuation ratio was 0.80 (range: 0.3-1.2); the craniocaudal liver span varied from 12 to 20 cm (mean=16 cm); hepatomegaly was present in 2 (22.2%) patients; the caudate-to-right lobe ratio was normal in all patients, with a mean of 0.36 (range: 0.22-0.47); the preportal space distance was enlarged in 2 cases (mean=7.5 mm, range: 1-16 mm); porta hepatis lymph nodes were present in 7 (77.8%) patients, and their mean dimensions were 11 mmx8 mm (large axis range: 6-19 mm, short axis range: 4-14 mm); and no patient had ascites. There was a significant difference in the craniocaudal liver span between patients with NASH (mean=21 cm) and patients with steatosis (mean=16 cm) (P<0.05). The caudate-to-right-lobe ratio was also significantly different between patients with NASH (mean=0.43) and patients with steatosis (mean=0.36) (P<0.05). There were no significant differences in liver-to-spleen attenuation ratios, measurements of preportal space, or the presence of porta hepatic lymph nodes. CONCLUSION: The CT features of NASH include steatosis, hepatomegaly, and porta hepatis lymph nodes, and the liver-to-spleen attenuation ratio correlated with the degree of steatosis on histopathology. Patients with NASH had a greater liver span and increased caudate-to-right-lobe-ratio compared with patients with steatosis alone.

Adult↗