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Servet Tatli

Publications and source records attributed to Servet Tatli.

12 recordsLinked to original sources

MRI-guided percutaneous cryoablation of renal tumors: use of external manual displacement of adjacent bowel loops.

PURPOSE: We sought to investigate retrospectively the safety and effectiveness of using external hand compression to displace adjacent bowel loops during MRI-guided percutaneous cryoablation of renal tumors. MATERIALS AND METHODS: Fourteen patients (six women, eight men; mean age: 72 years) with 15 renal tumors (mean diameter: 2.4 cm; range: 1.4-4.6 cm) adjacent to bowel were treated with MRI-guided percutaneous cryoablation during which bowel was displaced manually. Bowel loop of concern was ascending colon (n=5), descending colon (n=8), descending colon and small bowel (n=1), ascending colon and small bowel (n=1). To analyze effectiveness of the maneuver, mean distance between tumor margin and bowel before and after the maneuver were compared and analyzed using paired Student's t-test. Minimum distance between iceball edge and adjacent bowel with external manual displacement during freezing was also measured. Safety was assessed by analyzing post-procedural MR imaging for adjacent bowel wall thickening and focal fluid collections as well as patients' clinical and imaging follow-up. RESULTS: Mean distance between tumor margin and closest adjacent bowel increased from 0.8 cm (range: 0-2 cm) before external manual compression to 2.6 cm (range: 1.6-4.1 cm) with manual displacement (p<0.01). Mean minimum distance between iceball edge and closest adjacent bowel during the procedures was 1.6 cm (range: 0.5-3.5 cm). No evidence of bowel injury was encountered. Twelve of 15 tumors had follow-up (mean: 10 months) that showed no tumor recurrence. CONCLUSION: MRI-guided percutaneous cryoablation of renal tumors adjacent to bowel can be done safely and effectively using external hand compression to displace bowel loops.

Aged↗

Local staging of rectal cancer using combined pelvic phased-array and endorectal coil MRI.

PURPOSE: To assess the accuracy of MRI, using a pelvic phased-array coil and an endorectal coil, for preoperative local staging of rectal cancer. MATERIALS AND METHODS: Fifty-one patients (26 males and 25 females) with adenocarcinoma of the rectum underwent preoperative MRI and surgical resection of their tumors. Surgical pathology staging was compared to MRI staging (using the TNM classification) obtained both retrospectively by a reader blinded to surgical findings and prospectively (radiological reports). In addition, patients were stratified according to surgical treatment groups (stage I = T1-2/N0, stage II = T3/N0, stage III = Tx/N1-2). RESULTS: At pathology, 36 of 51 (68%) tumors were classified as T0-T2, and 15 (32%) were classified as T3. Overall, the sensitivity and specificity of MRI readings for T3 staging were 93% and 86%, respectively (positive predictive value (PPV) = 74%, negative predictive value (NPV) = 97%, accuracy = 88%). MRI correctly predicted lymph node metastases in 11 of 13 patients with a sensitivity of 85% and specificity of 69% (PPV = 58%, NPV = 90%, accuracy = 74%). MRI correctly predicted surgical treatment groups in 33 of 39 (85%) patients. Interobserver agreement between the retrospective and prospective readings was excellent (kappa = 0.85) for prediction of T3 tumor and good (kappa = 0.80) for prediction of nodal involvement. CONCLUSION: Combined endorectal and pelvic phased-array coil MRI can be used reliably to select which patients should receive preoperative chemoradiotherapy. It is highly predictive in terms of excluding T3 tumors, but still has limitations in predicting lymph node metastasis.

Adenocarcinoma↗

CT for intracardiac thrombi and tumors.

Although cardiac tumors are rare, they nevertheless represent an important subgroup, the diagnosis of which is challenging for the primary care physician. Symptoms are not characteristic and serious complications including stroke, myocardial infarction and even sudden death from arrhythmia may be the first signs of tumor. The most common primary cardiac neoplasm is the benign myxoma and the most frequent primary malignant lesion is sarcoma. Cardiac metastases from distant primary carcinomas are now frequently encountered. Echocardiography until the past decade was the only consistently reliable and available non-invasive diagnostic tool. New non-invasive CT and MRI exams are changing the diagnostic approach. Echocardiography and angiocardiography with or without coronary arteriography remain routine methods for evaluating cardiac neoplasms. However, CT provides additional diagnostic information and is regarded as essential for adequate staging and treatment planning, particularly when surgical resection is being considered. This chapter reviews the wide spectrum of intracardiac thrombi and tumors including their incidence and imaging characteristics with particular reference to the CT findings and differential diagnosis.

Coronary Thrombosis↗

CT and MRI features of pure acinar cell carcinoma of the pancreas in adults.

OBJECTIVE: We sought to describe the CT and MRI features of pure acinar cell carcinoma of the pancreas in adults. MATERIALS AND METHODS: Eleven patients (six women and five men; mean age, 64 years) with acinar cell carcinoma, documented by pathologic examination of resected specimens, underwent CT (n=9) or MRI (n=2) examinations. Two radiologists evaluated imaging studies and determined, by consensus, the following data for each tumor: size, location, margination, internal density or signal intensity, and contrast enhancement pattern. In addition, they assessed the presence of calcification, pancreatic or bile duct dilation, and metastases. Imaging features were correlated with gross and microscopic pathologic features of the tumors. RESULTS: Masses were distributed throughout the pancreas (head, n=5; body, n=2; and tail, n=4). The mean largest dimensions were 6.0 x 5.3 cm (range, from 2 x 1.7 to 15 x 11 cm). Tumors were oval (n=5), round (n=4), or lobular (n=2). Ten (91%) masses were well marginated; nine (82%) were exophytic. Five (45%) masses enhanced homogeneously; the remaining tumors contained cystic areas. All masses enhanced less than the surrounding pancreas. Three (27%) masses contained calcifications. Four (80%) masses invaded the duodenum. Common bile and pancreatic duct dilatation was present in two and three patients, respectively. One patient had metastatic liver disease at presentation. CONCLUSION: Pure acinar cell carcinoma of the pancreas is usually an exophytic, oval or round, well-marginated, and hypovascular mass on CT and MRI. It typically is completely solid when small and contains cystic areas due to necrosis when large.

Adult↗

Three-dimensional magnetic resonance imaging technique for myocardial-delayed hyperenhancement: a comparison with the two-dimensional technique.

PURPOSE: To compare two-dimensional and three-dimensional techniques in the detection of myocardial infarction (MI) and in the grading transmural extent (TE). MATERIALS AND METHODS: Twelve patients with clinically proven MI were examined using two-dimensional and three-dimensional techniques with cardiac-gated, breath-hold, T1-weighted gradient echo sequence with an inversion recovery pulse following gadopentetate dimeglumine (Gd-DTPA) at 0.2 mmol/kg. Contrast-to-noise, signal-to-noise, and signal intensity ratios (CNR, SNR, and SIR, respectively) were derived and compared for each technique. RESULTS: From two-dimensional to three-dimensional, statistical significant difference was found in the mean CNR (11.65 vs. 56.59; P = 0.002), SNR (18.03 vs. 76.90; P < 0.001), and SIR (3.6 vs. 6.36; P = 0.05). Intraobserver agreement (kappa) between two-dimensional and three-dimensional were R1 = 74% and R2 = 90%. Interobserver agreements between the readers were two-dimensional = 77% and three-dimensional = 79%. CONCLUSION: Mean CNR, SNR, and SIR are significantly increased in the three-dimensional technique compared to the conventional two-dimensional technique.

Adult↗

CT and MR imaging of the thoracic aorta: current techniques and clinical applications.

Disease of the thoracic aorta can present with a broad clinical spectrum of symptoms and signs. The accepted diagnostic gold standard, selective digital subtraction angiography, is now being challenged by state-of-the-art CT angiography (CTA) and MR angiography(MRA). Currently, in many centers, cross-sectional imaging modalities are being used as the first line of diagnosis to evaluate the cardiovascular system, and conventional angiography is reserved for therapeutic intervention. Understanding the principles of CTA and MRA techniques is essential to acquire diagnostic images consistently. This article reviews current CTA and MRA methods used in the evaluation of thoracic aortic disease.

Angiography↗

From the RSNA refresher courses: MR imaging of aortic and peripheral vascular disease.

Acquired diseases of the aorta and peripheral arteries are common. Owing to technical advances, magnetic resonance (MR) angiography has become the primary imaging modality for assessment of aortic and peripheral arterial disease. Contrast material-enhanced MR angiography is a rapid and robust technique that has emerged as the principal MR angiographic technique for evaluation of vascular disease. Two-dimensional time-of-flight MR angiography still has some well-validated applications, especially in distal peripheral vascular disease. Phase-contrast flow imaging is an important technique for quantification of blood flow. Black-blood imaging is a valuable tool for evaluation of the vessel wall. Understanding the principles of the main MR angiographic techniques is essential for consistent acquisition of diagnostic images. In addition, tailoring the acquisition parameters and the imaging protocol to the vessel being imaged and the clinical question is mandatory for optimal results. Future technical developments that will lead to faster image acquisition and better contrast agents promise to further improve image quality.

Adult↗

Thrombosed interrupted inferior vena cava and retroaortic left renal vein mimicking retroperitoneal neoplasm.

Anomalies of the inferior vena cava (IVC) have been recognized as one of the predisposing factors for deep vein thrombosis. Rarely, thrombosis of an anomalous retroperitoneal vein may resemble a soft tissue mass. Awareness of this fact helps preventing unnecessary interventions. We report a case of thrombosis of retroaortic left renal vein and interrupted IVC that mimicked a retroperitoneal neoplasm.

Abdominal Pain↗