Kyunghee C. Cho

Locoregional recurrences are frequent after radiofrequency ablation for hepatocellular carcinoma

BACKGROUND Enthusiasm for radiofrequency ablation (RFA) therapy for patients with unresectable hepatocellular carcinoma (HCC) has increased. The data for recurrence after RFA for patients with HCC is not well documented. The purpose of this study was to evaluate tumor recurrence patterns after RFA in patients with unresectable HCC. STUDY DESIGN Over a 3-year period, 50 patients having RFA for unresectable HCC were identified at a single institution. Medical records and radiologic studies were reviewed and outcomes factors analyzed. RESULTS Of the entire cohort, 46 patients underwent RFA by a percutaneous approach under CT guidance. Most patients underwent either one (n = 22) or two ablations (n = 23). At the time of this report, 14 patients (28%) were tumor-free by radiologic and biochemical (alpha-fetoprotein) parameters. Eighteen additional patients had persistence of tumor at the ablation site and 14 patients had recurrence in the liver at sites different from the ablation site. An additional four patients had recurrence in extrahepatic sites. Twelve patients underwent orthotopic liver transplantation after RFA. Of these 12, 5 (42%) demonstrated no viable tumor in the explanted liver. Independent predictors of tumor recurrence included tumor size, serum AFP levels, and the presence of hepatitis. CONCLUSIONS These data suggest that factors such as tumor size should be considered before employing RFA therapy. In addition to treating the primary tumor, other therapies aimed at the livers inflammatory state might also be important in achieving a durable response after RFA.

Intrapancreatic Accessory Spleen: Findings on MR Imaging, CT, US and Scintigraphy, and the Pathologic Analysis

Although the tail of the pancreas is the second most common site of an accessory spleen, intrapancreatic accessory spleen (IPAS) has rarely been noted radiologically. However, as the imaging techniques have recently advanced, IPAS will be more frequently detected as an incidental pancreatic nodule on CT or MRI. Because accessory spleens usually pose no clinical problems, it is important to characterize accessory spleens as noninvasively as possible. An IPAS has similar characteristics to those of the spleen on the precontrast and contrast-enhanced images of all the imaging modalities. In particular, inhomogeneous enhancement of an IPAS in its early phases may be a diagnostic clue. Superparamagnetic iron oxide (SPIO)-enhanced MRI and Levovist-enhanced US, and the mechanisms of which are theoretically similar to that of Tc-99m scintigraphy, can be used as alternative tools to confirm the diagnosis of IPAS. An IPAS shows a significant signal drop similar to the spleen on the SPIO-enhanced T2 or T2*-weighted imaging and prolonged enhancement on the delayed hepatosplenic phase of contrast-enhanced US. We review and illustrate the differential points between IPAS and hypervascular pancreatic tumors in this manuscript.

Colonic adenocarcinoma associated with the acquired immune deficiency syndrome.

Colonic adenocarcinoma developed in an intravenous drug abuser with the acquired immune deficiency syndrome (AIDS) that was diagnosed by the presence of antibodies to the human immunodeficiency virus (HIV), generalized lymphadenopathy, and biopsy proven esophageal candidiasis. The colon cancer presented atypically at a young age with no known risk factors and with a bulky primary tumor and a local fistula. AIDS and AIDS risk factors have been associated with Kaposis sarcoma, lymphomas, and anal and oropharyngeal carcinoma. This report suggests a possible association between colonic adenocarcinoma and AIDS.

CT Diagnosis of Mucocele of the Appendix in Patients with Acute Appendicitis

OBJECTIVE The purpose of this study was to identify the CT features of mucocele of the appendix coexisting with acute appendicitis and to determine whether this entity can be differentiated from acute appendicitis without mucocele. MATERIALS AND METHODS CT scans of 70 patients (12 with acute appendicitis with mucocele, 29 with acute appendicitis without mucocele, 29 with a normal appendix) were retrospectively interpreted by two readers. The appendix was evaluated for maximal luminal diameter, cystic dilatation, luminal attenuation, appendicolith, mural calcification and enhancement, periappendiceal fat stranding, fluid, and lymphadenopathy. CT findings were compared by use of Mann-Whitney U and Fishers exact tests. Receiver operating characteristics analysis was performed to assess the diagnostic utility of appendiceal luminal diameter in differentiating acute appendicitis with from that without coexisting mucocele. RESULTS Cystic dilatation of the appendix and maximal luminal diameter achieved statistical significance (p < 0.05) for the diagnosis of acute appendicitis with mucocele. Mural calcification achieved statistical significance for one reader (p = 0.0049) and a statistical trend for the other (p < 0.1). A maximal luminal diameter greater than 1.3 cm had a sensitivity of 71.4%, specificity of 94.6%, and overall diagnostic accuracy of 88.2% for the diagnosis of acute appendicitis with mucocele. CONCLUSION Although there is overlap with acute appendicitis without mucocele, CT features suggestive of coexisting mucocele in patients with acute appendicitis include cystic dilatation of the appendix, mural calcification, and a luminal diameter greater than 1.3 cm.

CT appearance in tuberculous pancreatic abscess

We report a case of a tuberculous pancreatic abscess in a 47-year-old human immunodeficiency virus positive intravenous drug abuser. She had a prolonged febrile course and persistent abdominal pain. On CT and sonography the lesion lacked the usual ancillary features of an abscess such as diffuse pancreatic enlargement and a peripancreatic fluid collection, and more closely resembled a necrotic neoplasm.

Focal enhancement of the liver on CT: a sign of SVC obstruction

We describe a case in which a focus of intense contrast enhancement within the anterior aspect of the medial segment of the left lobe of the liver was detected on abdominal CT. This led to the diagnosis of clinically unsuspected superior vena cava obstruction.

Effect of Flip Angle for Optimization of Image Quality of Gadoxetate Disodium–Enhanced Biliary Imaging at 1.5 T

OBJECTIVE The purpose of this study was to perform a qualitative and quantitative comparison of image quality of gadoxetate disodium-enhanced imaging of the biliary system acquired using different flip angles (FAs). MATERIALS AND METHODS Thirty-two patients (21 men and 11 women; mean [± SD] age, 51 ± 16 years) who underwent gadoxetate disodium-enhanced 1.5-T MRI were included. A 3D fat-suppressed T1-weighted gradient-echo sequence was acquired during the hepatobiliary phase using FAs of 12°, 25°, and 40°. One radiologist, who was blinded to FA, measured signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of the biliary tree. Two other blinded radiologists assessed subjective biliary duct clarity, overall image quality, background signal suppression, and ghosting artifact from the biliary tree using a scale of 1 to 4. RESULTS SNRs and CNRs of the common bile duct were significantly higher for FAs of 25° (227.5 ± 113.2 and 191.0 ± 102.2, respectively) and 40° (239.6 ± 118.7 and 201.7 ± 107.7, respectively) than for 12° (168.9 ± 73.9 and 126.7 ± 59.7, respectively; all p < 0.001). There were no significant differences in SNR or CNR between FAs of 25° and 40° (p ≥ 0.360). Clarity of first-, second-, and third-order intrahepatic ducts, background signal suppression, and overall image quality were significantly higher for both readers for FAs of 25° and 40° than for 12° (all p ≤ 0.031). None of these comparisons was significantly different for either reader between FAs 25° and 40° (all p ≥ 0.091), aside from improved depiction of third-order ducts at 40° for one reader (p = 0.030). Biliary ghosting artifact was significantly worse at 40° than at 12° for both readers (p ≤ 0.016). CONCLUSION The use of an FA larger than the clinical standard of approximately 12° has the potential to improve the image quality of gadoxetate disodium-enhanced biliary imaging.

Comparison of computed tomography and contrast enema evaluation of diverticulitis

A total of 31 patients with diverticulitis were analyzed who had both computed tomography and contrast enema. There was almost equal sensitivity to abnormality of approximately 90 percent. Contrast enema produced a specific diagnosis of diverticulitis in 61 percent, using stringent positive criteria, and an additional 29 percent with suggestive findings. Comparative computed tomography specific diagnoses in those 31 cases was made in 65 percent, and suggestive in 23 percent. Computed tomography was particularly useful diagnostically in cases of retrograde obstruction on contrast enema. The authors conclude that contrast enema should be the primary mode of approach, while computed tomography can be a valuable follow-up when the diagnosis is still in doubt, or if it is possible that patient management might be altered by additional information.

Hepatitis Status, Child-Pugh Classification, and Serum AFP Levels Predict Survival in Patients Treated With Transarterial Embolization for Unresectable Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) represents one of the most prevalent cancers worldwide. Most patients are not surgical candidates, and transarterial embolization (TAE) has been used to treat patients with unresectable HCC. The purpose of this study was to identify factors that predict survival in patients treated with TAE at a Western medical center. Review of a prospective database identi.ed 345 patients treated for HCC at University Hospital (Newark, NJ) between July 1998 and July 2004. Of these patients, 109 patients underwent TAE. Eleven of these patients were subsequently treated surgically and excluded from this study. Of the remaining 98 patients, demographic data and laboratory values were analyzed to predict survival by univariate and multivariate analysis. Several factors, including hepatitis status, Child-Pugh classification, serum alpha fetoprotein levels <500 ng/ml, bilirubin <2.0 mg/dl, prothrombin time <16 seconds, platelet count <200 × 10 9/l, albumin >3.5 gm/dl, and multiple treatments, predicted survival by univariate analysis. Serum alpha fetoprotein levels, Child-Pugh classification, and hepatitis status were found by multivariate analysis to independently predict survival. These factors may help to select patients with unresectable HCC who might benefit from TAE.

Liver infarction following unrecognized right hepatic artery ligation at laparoscopic cholecystectomy

Parenchymal liver complications thus far reported following laparoscopic cholecystectomy include abscess, biloma, contusion/laceration, and hematoma. We report a case of liver infarction following unrecognized ligation of the right hepatic artery (HA) during laparoscopic cholecystectomy.