Bulent Acunas

Hydatid disease with unusual localization

Abstract. Hydatid disease (HD) may develop in almost any part of the body. The liver is the most frequently involved organ (75 %), followed by the lung (15 %) and the remainder of the body (10 %). Hydatid cysts with unusual localizations may cause serious problems in the differential diagnosis. In this article the various imaging findings of hydatid cysts with unusual localizations are reviewed, based on our experience. Findings in brain, heart, pericard, kidney, intraperitoneum, retroperitoneum, bone, soft tissue, and breast are discussed. Hydatid disease should be considered in the differential diagnosis of all cystic masses in all anatomic locations, especially when they occur in areas where the disease is endemic. The combination of clinical history, imaging findings, and serologic test results usually help the diagnosis.

Imaging features of thalassemia

Abstract. Thalassemia is a kind of chronic, inherited, microcytic anemia characterized by defective hemoglobin synthesis and ineffective erythropoiesis. In all thalassemias clinical features that result from anemia, transfusional, and absorptive iron overload are similar but vary in severity. The radiographic features of β-thalassemia are due in large part to marrow hyperplasia. Markedly expanded marrow space lead to various skeletal manifestations including spine, skull, facial bones, and ribs. Extramedullary hematopoiesis (ExmH), hemosiderosis, and cholelithiasis are among the non-skeletal manifestations of thalassemia. The skeletal X-ray findings show characteristics of chronic overactivity of the marrow. In this article both skeletal and non-skeletal manifestations of thalassemia are discussed with an overview of X-ray findings, including MRI and CT findings.

Crohn Disease Activity Evaluated by Doppler Ultrasonography of the Superior Mesenteric Artery and the Affected Small-Bowel Segments

To reveal the disease activity in Crohn disease by gray scale and Doppler ultrasonography of the superior mesenteric artery (SMA) and the affected bowel segments.

Diffusion weighted MR imaging of pancreatic islet cell tumors

PURPOSE The aim of our study is to demonstrate the feasibility of body diffusion weighted (DW) MR imaging in the evaluation of pancreatic islet cell tumors (ICTs) and to define apparent diffusion coefficient (ADC) values for these tumors. MATERIALS AND METHODS 12 normal volunteers and 12 patients with histopathologically proven pancreatic ICT by surgery were included in the study. DW MR images were obtained by a body-phased array coil using a multisection single-shot echo planar sequence on the axial plane without breath holding. In addition, the routine abdominal imaging protocol for pancreas was applied in the patient group. We measured the ADC value within the normal pancreas in control group, pancreatic ICT, and surrounding pancreas parenchyma. Mann-Whitney U-test has been used to compare ADC values between tumoral tissues and normal pancreatic tissues of the volunteers. Wilcoxon Signed Ranks Test was preferred to compare ADC values between tumoral tissues and surrounding pancreatic parenchyma of the patients. RESULTS In 11 patients out of 12, conventional MR sequences were able to demonstrate ICTs succesfully. In 1 patient an indistinct suspicious lesion was noted at the pancreatic tail. DW sequence was able to demonstrate the lesions in all of the 12 patients. On the DW images, all ICTs demonstrated high signal intensity relative to the surrounding pancreatic parenchyma. The mean and standard deviations of the ADC values (x10(-3)mm(2)/s) were as follows: ICT (n=12), 1.51+/-0.35 (0.91-2.11), surrounding parenchyma (n=11) 0.76+/-0.15 (0.51-1.01) and normal pancreas in normal volunteers (n=12), 0.80+/-0.06 (0.72-0.90). ADC values of the ICT were significantly higher compared with those of surrounding parenchyma (p<0.01) and normal pancreas (p<0.001). CONCLUSION DW MR imaging does not appear to provide significant contribution to routine MR imaging protocol in the evaluation of pancreatic islet cell tumors. But it can be added to MR imaging protocol to detect the lesion in a limited number of patients with clinical suspicion for pancreatic ICT with negative or suspicious imaging findings.

Preoperative CT staging of colon carcinoma (excluding the recto-sigmoid region)

Twenty-eight patients with colon carcinoma (excluding the recto-sigmoid region) underwent preoperative staging with computed tomography (CT). The CT had a sensitivity and a specificity of 60 and 67% for detection of extramural invasion, 75% sensitivity and specificity for lymph node metastases and a sensitivity of 87% and specificity of 95% for liver metastases. Compared with the modified Dukes classification, CT correctly staged 50% of the patients with Dukes A lesions; 40% with Dukes B; 75% with Dukes C and 85% with Dukes D lesions. The data presented in this study showed that CT has limitations in the sensitivity and accuracy of staging local colonic carcinoma. However, we recommend its use for patients who are clinically suspected of having extensive disease.

Palliative treatment of inoperable malignant esophageal strictures with metal stents: one center's experience with four different stents.

PURPOSE Our centers experience with Ultraflex, Flamingo, SR stent and Flexstent for the palliation of malignant esophageal strictures is reported, and current pertinent literature is reviewed. MATERIAL AND METHODS Stents have been placed under fluoroscopic guidance between August 1993 and February 2002 for the palliation of malignant dysphagia in 116 patients. 59 patients received Ultraflex, 33 patients received Flamingo Wallstent, 20 patients received the SR stent and four patients received Flexstent. RESULTS Stent placement was successful in all the patients, with good symptomatic control in 123 out of 126 patients (98%) and no procedure-related complications. Four esophagorespiratory fistulas were successfully closed with covered Flamingo stents. Repeat intervention was necessary in 30 patients (51%) who received the Ultraflex stent, secondary to tumor ingrowth, overgrowth, ulceration, fistula and incomplete expansion. Two patients (6%) who received Flamingo Wallstent died due to gastrointestinal bleeding and one patient had proximal migration. Four patients (20%) who received the SR stent had complete migration of the stent. CONCLUSION Covered stents were found to provide better long-term palliation compared to uncovered stents. The covered Flamingo Wallstent seems to be the best choice of stent for lesions where crossing the esophagogastric junction is not necessary. For lesions where it is mandatory to cross the junction it may be preferable to use a stent with an antireflux mechanism.

Granulomatous mastitis: Gray‐scale and color Doppler sonographic findings

We examined the roles of gray‐scale and color Doppler sonography in the diagnosis of granulomatous mastitis.

Hepatocellular carcinoma: treatment with transcatheter arterial chemoembolization.

This article presents a review of the literature regarding the use of transcatheter arterial chemoembolization (TACE) in the treatment of hepatocellular carcinoma (HCC). There have been two different approaches to the treatment: (a) percutaneous tumor ablation methods which can be divided into injectable and thermal methods; percutaneous ethanol injection (PEI) is the most widely used method, and (b) TACE. PEI is the treatment of choice for single HCCs smaller or equal to 3 cm in size. For patients with large HCCs combined TACE and PEI is probably the most effective nonsurgical treatment. In the presence of multiple HCC nodules, TACE remains the treatment of choice.

Intervention in gastrointestinal tract: the treatment of esophageal, gastroduodenal and colorectal obstructions with metallic stents

With the development of newer stent designs and delivery systems, metallic stents are currently established component of nonsurgical treatment of gastrointestinal obstructions. The use of metallic stents is not intended to be curative but palliative. This palliation may be intended for the rest of the patients life with unresectable disease or as a temporary procedure prior to a definitive surgical procedure to allow time to improve the patients overall medical condition or quick and noninvasive decompression of the intestinal obstruction.

Hepatic alveolar echinococcosis: MRI findings

The purpose of this study was to describe the magnetic resonance imaging (MRI) appearance of hepatic alveolar echinococcosis (HAE) on T(1)-weighted, T(2)-weighted and postgadolinium images. A total of 13 lesions were demonstrated in 13 patients. All patients underwent MR examination at 1 T imager. MR examinations included precontrast T(1)-weighted breathing averaged spin echo (SE), breath-hold spoiled gradient echo, T(2)-weighted TSE sequences with and without fat suppression, and T(1)-weighted breath-hold spoiled gradient echo (SGE) sequence following i.v. after gadolinium administration. All lesions were confirmed with histopathology. HAE hepatic lesions revealed geographic patterns of variable signal intensities on noncontrast T(1)- and T(2)-weighted images. Slightly hyperintense, iso- and hypointense signal on T(1)-weighted images corresponded to calcified regions, which appeared hypo-isointense signal on T(2)-weighted images. Necrotic areas were hypointense signal on T(1)-weighted and hyperintense signal on T(2)-weighted images. On postgadolinium images, lesions did not reveal enhancement. Dilatation of intrahepatic bile ducts distal to HAE abscesses were observed in five patients and portal vein invasion or compression was observed in four patients, lobar atrophy of the liver was coexistent finding in cases with portal vein compression. The MRI appearance of HAE abscesses included large irregularly marginated masses with heterogenous signal on T(1)- and T(2)-weighted images and lack of enhancement with gadolinium.