MDCT findings in neuroendocrine carcinoma of the gallbladder: case report.

Neuroendocrine tumors are commonly seen in the gastrointestinal tract, but they are extremely rare in the gallbladder. In this study, sonographic and multidetector-row computed tomographic findings of a patient with neuroendocrine tumors of the gallbladder are presented.

CT findings of non-functioning neuroendocrine pancreatic tumors.

Neuroendocrine tumors are rare neoplasms of the pancreas, representing 0.5% of all pancreatic tumors. Approximately, one-third of neuroendocrine tumors are hormonally inactive and called non-functioning neuroendocrine tumors. As these tumors remain clinically silent in their course of growth, they may attain great sizes without causing apparent clinical findings and commonly present in advanced stage. We report three cases of non-functioning neuroendocrine tumors with large sizes and discuss the radiological findings.

Lipoma of the pancreas: MRI findings.

Lipomas of the pancreas are very rare. Focal fatty infiltration of the pancreas is an entity that should be differentiated from a pancreatic lipoma. In this report the MRI findings of an incidentally found pancreatic lipoma are presented and the role of MRI in the differentiation of pancreatic lipoma and focal fatty infiltration of the pancreas is discussed.

Aneurysmal dilatation of the paraumbilical vein in an infant.

The paraumbilical veins are one of the most common collateral pathways developing in portal hypertension. Aneurysmal dilatation of a patent paraumbilical vein is a very unusual finding. We report the first infant case of a paraumbilical vein aneurysm and its Doppler ultrasound findings.

Various radiological appearances of angiomyolipomas in the same kidney.

A 21-year-old woman with tuberous sclerosis presented with abdominal distension and flank pain. Imaging studies, including CT and MR imaging, revealed bilateral renal mass lesions, containing fat and suggesting the diagnosis of tuberous sclerosis. However the imaging characteristics of one of these lesions differed from the others with no radiologically detectable fat tissue in this solid lesion suggesting renal cell carcinoma. Histopathological examination of this lesion in the left kidney revealed an angiomyolipoma within minimal fat tissue. The radiological diagnosis of angiomyolipomas with minimal fat tissue remains difficult and the differential diagnosis is discussed.

Subcapsular hemorrhage of adult Wilms' tumor.

Wilms' tumor is a rare malignancy of kidney in adults. It usually cannot be differentiated from other renal masses preoperatively. This is a presentation of a case of adult Wilms' tumor who developed spontaneous hemorrhage during radiological evaluation. As tumor rupture can change the stage of the tumor and alter the prognosis of the patient, urgent work-up and treatment is advised.

Esophageal duplication cyst coexisting with Bochdalek's hernia and polysplenia.

Esophageal duplication cyst, Bochdalek's hernia and polysplenia are uncommon congenital anomalies which have not been reported to be associated with each other. We present the radiological aspects of an unusual coexistence of these three congenital anomalies in a 4-month-old girl.

Renal, gastric and thyroidal amyloidosis due to familial Mediterranean fever.

Chronic renal failure developed in a 10-year-old girl due to renal amyloidosis secondary to familial Mediterranean fever (FMF). During management of the chronic renal failure by hemodialysis and of FMF with colchicine, goiter and hypothroidism were observed. Thyroid fine-needle aspiration and gastric endoscopical biopsies, performed when recurrent abdominal pain could not be controlled, revealed amyloid deposits in both thyroid and gastric tissues. After 6 months' therapy with colchicine and levothyroxine, there was no significant change in the thyroid volume. This is the first case in which gastric amyloidosis secondary to FMF in childhood has been demonstrated. Patients with amyloidosis secondary to FMF who have thyroid enlargement and unexplained gastrointestinal symptoms despite adequate therapy should be evaluated with imaging studies and biopsy examinations.

The prokinetic effect of domperidone in gallbladder--not upon dopaminergic receptors.

The mechanism of the contractile effect of domperidone on gallbladder smooth muscle has been investigated by using an in-vivo and an in-vitro model. In the in-vivo part of the study 14 healthy males were administered 20 mg domperidone or two placebo tablets orally and gallbladder emptying was measured by ultrasonography. The reduction in the gallbladder volume was significant compared to the placebo at 45 and 55 min. In the in-vitro part of the study, the gallbladder strips isolated from guinea pigs were field stimulated and 10(-6)-10(-4) M concentrations of dopamine were administered before electrical field stimulation (EFS) was repeated. Dopamine exerted no significant effect upon the contractions obtained by EFS. The effect of dopamine and domperidone under basal conditions were also explored. Under basal conditions, dopamine neither contracted nor relaxed the gallbladder muscle between 10(-6) and 10(-4) M concentrations when added directly to the organ bath. Besides, a significant contraction was observed with 10(-4) M concentration of domperidone whereas 10(-7), 10(-6) and 10(-5) M concentrations exerted no effect. This effect of domperidone was thought to be nonspecific but inhibited by 10(-6) M atropine, 10(-5) M pirenzepine and abolished by 10(-6) M tetrodotoxin. In summary, domperidone produces a modest contraction in human gallbladder. This effect does not seem to occur upon dopaminergic receptors in guinea pig models.

99mTc-MIBI scintigraphy in metastatic renal cell carcinoma: clinical validation of the relationship between 99mTc-MIBI uptake and P-glycoprotein expression in tumour tissue.

Technetium-99m hexakis-2-methoxyisobutylisonitrile (MIBI) and thallium-201 imaging was performed in a patient with metastatic renal cell carcinoma (RCC), which is a well-known tumour type demonstrating P1-glycoprotein (PGP) overexpression. Two scintigraphic patterns - Tl(+)/MIBI(-) in primary tumour and Tl(+)/MIBI(+) in metastatic tumour - were observed, suggesting high- and low-level PGP expression, respectively. Immunochemical study for PGP revealed strong staining of the primary tumour cells. This case clinically validates the previously suggested relationship between 99mTc-MIBI uptake and PGP expression.

Early and delayed thallium-201 scintigraphy in thyroid nodules: the relationship between early thallium-201 uptake and perfusion.

Seventy-six patients with thyroid nodules were studied. Initially, 74 MBq of thallium-201 was injected. The thyroid gland was imaged 15 min (early) and 3 h (delayed) after the injection. Thereafter, 185 MBq technetium-99m pertechnetate was injected. Immediately after the injection, a 1-min perfusion image was acquired, followed by an image at 20 min. Increased early and delayed 201Tl uptake compared with the contralateral thyroid tissue was adopted as the criterion for malignancy. Sensitivity, specificity and negative predictive values were found to be 85%, 64% and 78%, respectively, in operated patients, but these values were 86%, 87% and 95%, respectively, in the whole group, including patients followed with fine-needle aspiration biopsy. With the purpose of investigating the relationship between perfusion and early 201Tl uptake, both perfusion and early images were graded comparing nodular activity with contralateral thyroid activity. There was a poor correlation between perfusion and 201Tl uptake. The correlation was even worse in hyperactive nodules. It is concluded that early and delayed 201Tl imaging should not be used in the differential diagnosis of cold nodules and that early 201Tl uptake seems to be more closely related to factors other than perfusion.

Lingual thyroid: the diagnostic value of magnetic resonance imaging.

Lingual thyroid is an uncommon developmental aberration of embryogenesis. It may present as a mid-line, non-tender, painless, reddish appearing swelling in the throat. Magnetic resonance imaging (MRI) is a relatively new diagnostic method for this condition. Two cases of lingual thyroid are reviewed with their MRI's and surgical results.