Nobuaki Miyazono

Lymphoepithelial cysts of the pancreas: demonstration of lipid component using CT and MRI.

We present two cases of surgically proven lymphoepithelial cyst (LEC) of the pancreas that had a lipid component visualized by CT and MRI. Identification of this component in a pancreatic cystic lesion is a key to favor the diagnosis of LEC or splenic epidermoid cyst over other cystic lesions when the lesion is noted in an elderly patient.

Embolization of the hepatic falciform artery to prevent supraumbilical skin rash during transcatheter arterial chemoembolization for hepatocellular carcinoma

A dilated hepatic falciform artery (HFA) arising from the left hepatic artery was demonstrated on arteriography prior to chemoembolization of an unresectable hepatocellular carcinoma (HCC) located predominantly in the left lobe of the liver. The HFA was occluded by microcoils to prevent a possible toxic supraumbilical skin rash following chemoembolization of the HCC via the left hepatic artery. There were no postprocedure complications. We consider this procedure useful for improving the safety of chemoembolization.

HEPATIC FALCIFORM ARTERY: Angiographic findings in 25 patients

Purpose: To determine the frequency of hepatic falciform artery (HFA) occurrence on celiac or hepatic angiograms and elucidate the anatomy and clinical importance. Material and Methods: Among 1,250 patients who underwent celiac or hepatic arteriography, we encountered 25 patients (2%) with a HFA. Prospectively, CT hepatic falciform arteriography (CTHA) was performed in 4 patients. Indigocarmine dye was injected into the HFA in 6 patients to evaluate whether the abdominal skin was stained. Embolization of the HFA before chemoembolization for hepatocellular carcinoma was performed in 4 patients to prevent abdominal wall injury. Results: Among 25 patients, the HFA arose as a terminal branch of the middle hepatic artery in 14 patients (56%) and of the left hepatic artery in 11 patients (44%). The vessel was single in 18 patients (72%) and double in 7 patients (28%). Two vessels ran side by side along the hepatic falciform ligament. On CTHA, the HFA ran within the hepatic falciform ligament and the branches were connected with the liver around the hepatic falciform ligament. After indigocarmine dye injection, the stain of abdominal skin was recognized in all 6 patients. No abdominal wall injury occurred in any of the 4 patients who were subjected to hepatic chemoembolization. Conclusion: HFA is an extrahepatic pathway which runs to the abdominal wall. Before chemoembolization of the middle or left hepatic artery for hepatic malignancy, the HFA should be recognized.

LOCALIZATION OF INSULINOMAS: Comparison of conventional arterial stimulation with venous sampling (ASVS) and superselective ASVS

Purpose: To examine the value of superselective arterial stimulation venous sampling (ASVS) to localize insulinomas. Material and Methods: Superselective ASVS (SS-ASVS) was performed in 9 patients with insulinoma. Injection of secretagogue (calcium gluconate: 0.01 mEq Ca++/kg) was performed into the gastroduodenal, splenic (proximal and distal), and superior mesenteric arteries in 9 patients and additionally into the dorsal pancreatic artery in 6 patients. Sampling from the hepatic vein was performed to measure serum insulin concentrations at 30, 60 and 120 s after each injection of secretagogue into these arteries. SS-ASVS results were correlated with surgical findings, compared to those of conventional ASVS. Results: Insulinomas were correctly localized to the head, body or tail of the pancreas by SS-ASVS in 8 patients (89%). Conventional ASVS detected insulinomas in 7 patients (78%), although it could not distinguish whether the insulinoma was located in the pancreatic body or tail in 4 of the 7 patients. There were eight-fold or more increases in serum insulin levels in hepatic venous samples related to the artery supplying the tumor in 8 patients. Localization of the insulinomas was verified at surgery in all patients. Conclusion: SS-ASVS is a useful method for detailed evaluation of overproduction of insulin from pancreatic insulinomas and their localization. When the pancreatic insulinoma is situated in the pancreatic body or tail, the localization is more accurately made by SS-ASVS than by conventional ASVS.

Altered flow dynamics of intravascular contrast material to the liver in superior vena cava syndrome: CT findings

AbstractBackground: To evaluate the findings of altered flow dynamics in the livers of patients with obstruction of superior vena cava (SVC) on helical computed tomography (CT). Methods: In six patients (age range = 28–80 years) with SVC obstruction, CT findings were retrospectively reviewed to identify the abnormal enhancement patterns of the liver and the relation with the extrahepatic collateral vessels and hepatic vessels. Results: Abnormal hepatic enhancement was observed in the following four (A–D) portions: (A) anterior portion of segment IV (n = 5), (B) subdiaphragmatic portion of the liver (n = 4), (C) posterior portion of the right lobe (bare area; n = 1), and (D) lateral segment of the left lobe (n = 2). Two major collateral pathways to the liver were demonstrated as follows: A and D → from the umbilical vein to the left portal vein, and B and C → from the subcapsular vein to the bare area of the liver or to the hepatic veins. On helical CT, these collateral pathways were also clearly visualized. Conclusion: When these abnormal enhancements of the liver on CT are recognized within the liver, these findings indicate diversion of contrast material into collateral pathways to the liver with SVC obstruction.

Visualization of left bronchial-to-coronary artery communication after distal bronchial artery embolization for bronchiectasis

We present a 44-year-old woman in whom a bronchialto-coronary artery communication via the conus branch was discovered after distal bronchial artery embolization with gelatin sponge for hemoptysis. If this bronchial-to-coronary artery anastomosis, not visible prior to embolization, had been inadvertently embolized, the patient could have developed a myocardial infarction. To reduce the likelihood of a serious complication, the possibility of this anastomosis should be kept in mind and angiography should be repeated before attempting proximal bronchial artery embolization.

A case of renal juxtaglomerular cell tumor: usefulness of segmental sampling to prove autonomic secretion of the tumor.

A 27-year-old female patient had been treated for hypertension with conventional therapy for years, because renal vein renin levels failed to show lateralization in renal venous samplings and a renal juxtaglomerular cell tumor (RJGCT) had gone undiagnosed. Abdominal computed tomography revealed a mass at the middle of the right kidney. The right renal venogram demonstrated distinct segmental veins from the upper pole and from the middle and lower poles in the right kidney. On segmental renin sampling from each renal vein, the plasma renin concentration (PRC) of the segmental veins from the middle and lower poles was higher than that from other sites. We diagnosed RJGCT of the right kidney and performed right-sided nephrectomy. After the resection, the PRC rapidly decreased. Immunohistochemical studies using antihuman renin antibodies revealed positive staining of the tumor cells. It is an important strategy to make a segmental sampling at the site as close as possible to the RJGCT.

Small hepatocellular carcinoma supplied by the right renal capsular artery. A case report.

We present a case of hepatocellular carcinoma (HCC), which was fed only by the right renal capsular artery. Ten years earlier, this patient underwent surgery for a solitary HCC in segment IV. However, the hepatic artery was patent and did not participate in feeding the HCC. We consider the renal capsular artery as an essential extrahepatic parasitic feeding artery to HCC.

Retrograde visualization of the portal venous system using CO2 intraarterial digital subtraction angiography

Carbon dioxide (CO2) intraarterial digital subtraction angiography (IADSA) provides retrograde visualization of the portal vein via a peripheral segmental hepatic artery. IADSA was performed in 12 patients with known hepatic diseases by injecting a peripheral hepatic artery with both CO2 gas and an iodinated contrast medium. The portal vein was constantly visualized only with CO2 IADSA in all patients. The injected CO2 may flow back into the portal vein through an anastomotic system known as the peribiliary or periportal plexus. This new method is safe and useful to image the portal venous system in patients with hepatic malignancy.

Transcatheter Adrenal Arterial Embolization of Cortisol-Producing Tumors

Transcatheter arterial embolization (TAE) was performed in 2 patients with Cushings syndrome caused by adrenal adenoma by using a mixture of absolute ethanol and iohexol. In 1 patient successful suppression of the hypersecretion of cortisol has continued for 9 months after TAE without complications. However, in the other patient, TAE was discontinued due to marked hypertension and tachycardia induced by a massive release of catecholamines from the embolized “normal” part of the tumor-bearing adrenal gland during the procedure. These results suggest that it is important to perform TAE of only the arterial branches feeding the tumor.