Ciliated hepatic foregut cyst (CHFC) is a rare benign lesion consisting of ciliated pseudostratified columnar epithelium, loose subepithelial connective tissue, a smooth muscle layer, and an outer fibrous capsule. We encountered a patient with retroperitoneal and posterior mediastinal neurilemmoma and additional CHFC mimicking metastasis. Abdominal CT examination demonstrated that the posterior mediastinal and retroperitoneal lesions were lobulated, well-defined tumors with a neural foraminal extension that were pathologically confirmed as neurilemmomas. Unenhanced CT indicated that the additional lesion was a slightly hypodense mass relative to surrounding parenchyma at the medial segment of the left lobe of the liver, and after the IV ad-ministration of contrast material, the lesion did not show enhancement.
Connective Tissue ; Epithelium ; Humans ; Liver ; Muscle, Smooth ; Neoplasm Metastasis* ; Neurilemmoma ; Tomography, X-Ray Computed

No abstract available.
Lung Neoplasms* ; Lung* ; Neoplasm Metastasis* ; Toes*

No abstract available.
Lasers, Solid-State* ; Papilloma*

OBJECTIVE: To compare the performance of superparamagnetic iron oxide (SPIO) -enhanced magnetic resonance (MR) imaging at 1.5T and dual-phase spiral computed tomography (CT) for the depiction of small hypervascular hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: Forty-three patients with 70 small nodular HCCs (5-20 mm; mean, 13.7 mm) were examined. Diagnosis was based on the results of surgical biopsy in 22 patients and by the combined assessment of MR imaging, lipiodol CT, alpha feto-protein levels, and angiographic findings in 21. MR imaging consisted of respiratory-triggered turbo spin-echo T2-weighted imaging, T1-weighted fast low-angle shot, and T2* -weighted fast imaging with steady-state precession imaging before and after SPIO enhancement. CT imaging was performed with 5-mm collimation and 1: 1.4 pitch, and began 30 and 65 secs after the injection of 150 mL of contrast medium at a rate of 3 mL/sec. Two blinded observers reviewed all images independently on a segment-by-segment basis. Diagnostic accuracy was evaluated using receiver operating characteristics (ROC) analysis. RESULT: The mean areas (Az) under the ROC curves were 0.85 for SPIOenhanced MR imaging and 0.79 for dual-phase spiral CT (p < .05). The mean sensitivity of SPIO-enhanced MR imaging was significantly higher than that of CT (p < .05), i.e. 70.6% for MR imaging and 58.1% for CT. MR imaging had higher false-positive rates than dual-phase spiral CT, but the difference was not statistically significant (3.7% vs 3.3%) (p > .05). CONCLUSION: SPIO-enhanced MR imaging is more sensitive than dual-phase spiral CT for the depiction of small hypervascular hepatocellular carcinomas.

PURPOSE: To compare liver hemangioma with hepatocellular carcinoma (HCC), as seen on superparamagneticiron oxide (SPIO)-enhanced MR images. MATERIALS AND METHODS: The study involved 30 patients with 51 focal hepatic mass lesions (31 hemangiomas, 20 HCCs). Breath-hold T1-weighted fast low angle shot (FLASH) and respiratory-triggered T2-weighted turbo-spin echo (TSE) images were obtained at 1.5 T before and after intravenous administration of SPIO particles. For quantitative analysis, percentage signal intensity change (PSIC) and contrast-to-noise ratio (CNR) of the lesions were calculated for T1-weighted FLASH and T2-weighted TSE before and after intravenous administration of SPIO particles. In addition, lesion conspicuity and imaging artifacts were analyzed qualitatively. RESULTS: After SPIO administration, percentage signal intensity increase on T1-weighted FLASH images was 73.0 +/-22.1% for hemangiomas and 21.8 +/-12.6% for HCCs, the difference being significant (p < 0.05). Taking a signal increase of 40% on postcontrast T1-weighted FLASH as the cut-off value, sensitivity and specificity for hemangiomas were 96.8% and 100%, respectively. In addition, the percentages of signal intensity loss on T2-weighted TSE images for hemangiomas and HCCs were 35.5 +/-17.2% and 0.2 +/-10.5%, respectively (p < 0.05). A comparison of lesion to liver CNR before and after SPIO infusion showed readings-for hemangiomas and HCCs, respectively - of 15.4 +/-6.0 and 4.7 +/-4.4 on T1-weighted FLASH images, and -2.6 +/-0.7 and 2.7 +/-4.4 on T2-weighted TSE images (p < 0.05). Qualitative analysis indicated that the conspicuity of HCCs was noticeably greater on postcontrast T2-weighted TSE images than on precontrast images (p < 0.05). CONCLUSION: The positive enhancement seen on T1-weighted FLASH images and the negative enhancement on T2 weighted TSE observed in liver hemangiomas after the administration of SPIO particles are valuable diagnostic features that can help characterize hemangiomas and differentiate them from HCCs.
Administration, Intravenous ; Artifacts ; Carcinoma, Hepatocellular* ; Hemangioma* ; Humans ; Iron* ; Liver ; Magnetic Resonance Imaging* ; Sensitivity and Specificity

We describe a case of poorly differentiated gastric neuroendocrine carcinoma presenting as a wandering exophytic mass. CT imaging revealed a 14.5x10.0x8.0 cm, lobulated, solid mass with a multifocal necrotic portion at the right of the peritoneal cavity. It was attached to the antrum of the stomach by a broad stalk, and shown by MR imaging to be well-defined, lobulated and solid, with a multifocal necrotic portion, and at the left of the peritoneal cavity. Isointensity was apparent at T1-weighted imaging, and slightly hyperintensity at T2-weighted imaging, and after gadolinium injection, enhancement was stronger than at precontrast imaging.
Carcinoma, Neuroendocrine* ; Gadolinium ; Magnetic Resonance Imaging ; Peritoneal Cavity ; Stomach

PURPOSE: We wanted to evaluate the efficacy and safety of using ultrasound guided percutaneous radiofrequency ablation for the benign nodules of the thyroid gland. MATERIALS AND METHODS: We studied 148 patients with benign thyroid nodules (200 total nodules) that were confirmed histopathologically, and we performed ultrasound guided radiofrequency ablation. The radiofrequency ablation was done 1 to 5 times per one nodule, and follow-up ultrasonography was performed one to nineteen months after the ablation procedures. The physical changes and the decrease of volume of the nodules were evaluated, and the complications related to radiofrequency ablation were observed. RESULTS: The mean initial nodule volume was 0.01-95.61 ml (mean; 6.83+/-SD of 10.63 ml) and the nodule volume after radiofrequency ablation was decreased to 0.00-46.56 ml (mean; 1.83+/-SD of 4.69 ml). The mean volume reduction rate was 73.2%. Reduction of more than 50% was noted in 90% of all cases. For 180 nodules (90%), the decrease was 50% or more, in 20 nodules (10%), the decrease was 49% or less. On gray-scale ultrasonogram obtained after ablation, the echogenicity of the nodules changed to darker, and on the doppler-sonogram, the vascular flow within the nodules disappeared in all cases. Most patients complained pain during or right after the procedure, but the pain was transient and subsided after medication. Two patients developed hoarseness that was improved in 1 week and 2 months, respectively. CONCLUSION: Sonoguided percutaneous radiofrequency ablation can be one of the treatments for benign nodules of the thyroid gland.
Catheter Ablation* ; Follow-Up Studies ; Hoarseness ; Humans ; Thyroid Gland* ; Thyroid Nodule ; Ultrasonography

This study was undertaken to compare renal damage, as determined by serum creatinine and degree of apoptosis, caused by iodinated contrast or gadolinium in an acute renal failure (ARF) rat model. Rats were divided into three groups; controls (n=3), a CT contrast medium group (n=9), and an MR contrast medium group (n=9). The CT and MR groups were further subdivided into three groups, namely, low, standard, and high dose subgroups. Renal function was evaluated by determining serum creatinine levels; before ARF, and 48 hr after ARF and contrast administration. Apoptosis was assayed by terminal deoxynucleotidyl transferasemediated dUTP nick-end labeling (TUNEL). No significant creatinine level differences were observed between the CT and MR groups (p=0.116). Degrees of apoptosis in the renal cortex and medulla were more severe in the CT contrast medium group than in the control or MR contrast medium group (p<0.05). The study shows that CT contrast medium did not aggravate renal function more so than MR contrast medium in this ARF rat model. However, apoptosis examination in the renal cortex and medulla indicated that CT contrast medium induced more severe apoptosis than MR contrast medium (p<0.05). We conclude that CT contrast medium can be used for renal imaging studies when subjects are well hydrated and preventive medication is administered.
Animals ; Apoptosis/*drug effects ; Contrast Media/adverse effects ; Creatine/*blood ; Female ; Gadolinium DTPA/*adverse effects ; Iohexol/adverse effects/*analogs and derivatives ; Kidney/*drug effects/*pathology ; Kidney Failure, Acute/*blood/pathology/radiography ; Male ; Rats ; Rats, Sprague-Dawley ; Research Support, Non-U.S. Gov't

PURPOSE: Urinary red blood cell morphology has been used to localize the site of hematuria in the urinary tract. But the pathologic mechanism for dysmorphic urinary red blood cells remains undefned. Our study was undertaken to investigate the mechanism of dysmorphic urinary RBCs in glomerular hematuria. We have attempted to reproduce in vitro the changes that occur in red cell morphology during passage through the renal tubule and to elucidate the role of urinary composition in determining morphology. METHODS: We examined a number of urinary samples under bright f eld microscopes with Wright's stain. 1) One drop of fresh venous blood was added to 1 ml experimental fluid, allowed to stand for 5 min and then assessed. The experimental fluids used were NaCl solutions in which the sodium concentration varied among 40 and 400mmol/L and similar saline solutions to which KCl(10, 50mmol/L), CaCl2(0.5, 2mmol/L), Urea(100, 400mmol/L) and pH(4, 8) had been added. We examined the RBC morphology in these solution. 2) In order to simulate passage of RBCs through the renal tubule, RBCs were initially suspended for 5 min in hypertonic solutions(NaCl 200mmol/L+Urea 70mmol/L+Urea 1000mmol/L). The RBCs were separated by centrifuging at 500rpm for 2 min in conical tubes, the supernatant was discarded and the RBCs washed and resuspended in a hypotonic solution(NaCl 60mmol/L) for 5 min. We added two urines(610mOsm/Kg H2O) to these solutions and then examined the RBCs morphology. RESULTS: The results were as follows; 1) Anisocytosis and hypochromia were found in NaCl 60mmol/L and 75mmol/L solutions and crenated RBC was found in Nacl 400mmol/L solution. But addition of potassium, calcium or urea and variation of the pH had no effect on red cell morphology. 2) when exposed to hypotonic solution, which simulated tubular condition(NaCl 60mmol/L), the RBCs became anisocytotic and hypochromic. These two features were particularly marked if cells were transferred to concentrated urine(610mOsm/kg H2O). CONCLUSIONS: It is evident that a hypotonic tubular condition is hostile for red cells and may be primarily responsible for hy0pochromia and anisocytosis of RBCs. Although two characteristic features of dysmorphism can be reproduced in vitro, a the bizarre deformity cannot be observed. Therefore passage of red cells through the hypotonic tubular segment alone does not account for the typical deformity. Because dilute urine specimens give a false impression by selective lysis of dysmorphic cells, concentrated urine is suitable for analysis of red cell morphology.
Calcium ; Congenital Abnormalities ; Erythrocytes ; Hematuria* ; Hydrogen-Ion Concentration ; Potassium ; Sodium ; Urea ; Urinary Tract

PURPOSE: We wanted to analyze the peripheral calcification patterns of thyroid tumors that were seen on ultrasound and we also wanted to evaluate the clinical usefulness of the peripheral calcifications of the thyroid tumors. MATERIALS AND METHODS: We retrospectively analyzed 21 peripheral calcifications of the thyroid tumors of 18 patients; these were histopathologically confirmed by fine needle aspiration biopsy, automated gun biopsy and surgery. The peripheral calcification patterns were categorized into three types: type 1, peripheral nodular calcification, type 2, peripheral smooth rim calcification, and type 3, peripheral irregular rim calcification. The histopathologic results obtained during surgery, fine needle aspiration or automated gun biopsy were compared. RESULTS: Of the total 21 peripheral calcifications of thyroid tumors, 5 cases showed as being type 1 (24%), 3 cases showed as being type 2 (14%) and 13 cases showed as being type 3 (62%). Of the total 21 peripheral calcifications of the thyroid tumors, 18 were histopathologically confirmed as papillary carcinoma (86%). Among the type 1 peripheral calcification patterns, 3 cases were coincidentally diagnosed as papillary carcinoma and 2 cases were follicular neoplasm on the preoperative biopsy results and on the surgical results. Two cases of type 2 peripheral calcifications (67%) and three cases of type 3 peripheral calcifications (23%) were diagnosed as benign lesions upon preoperative biopsy, but the postoperative results were papillary carcinoma. CONCLUSION: Peripheral calcifications of thyroid tumors are important feature that suggest malignancy together with the microcalcification and peripheral calcifications of the type 2 and type 3 patterns, and these lesions may be difficult to accurately diagnose with using only biopsy.
Biopsy ; Biopsy, Fine-Needle ; Carcinoma, Papillary ; Humans ; Retrospective Studies ; Thyroid Gland* ; Ultrasonography*