Anatomy and clinical importance of cholecystic venous drainage: helical CT observations during injection of contrast medium into the cholecystic artery

Benign pericholecystic regeneration mimicking hepatocellular carcinoma: a potential pitfall in imaging of cirrhosis

Several pseudolesions mimicking malignancy have been reported in cirrhotic and non-cirrhotic livers. Pericholecystic regeneration is among those pseudolesions and can occasionally mimic malignancy. Herein we present a case series comprised of 10 cirrhotic patients (majority due to alcoholic liver disease [ALD] or metabolic dysfunction associated steatotic liver disease [MASLD]) with pericholecystic observations initially categorized as highly suspicious for HCC (LR-4 and LR-5) due to their suspicious enhancement pattern which were later proven to be benign based on biopsy, transplantation or imaging criteria (stability of size and morphology on serial CT or MRI for > 2 years). These observations ranged 2-6.3 cm in size, were multiple in most patients and universally resulted in indentations of gallbladder. Arterial phase hyperenhancement and washout, features usually attributed to hepatocellular carcinoma (HCC), were seen in most patients. However, ancillary features of malignancy such as diffusion restriction, increased T2 signal, and hypointensity on hepatobiliary phase MRI were not present. Pericholecystic observations, in particular in the setting of ALD and MASLD, should be carefully assessed and possibility of pseudolesion should be considered especially when the observations are multiple, cause indentation of gallbladder, and lack ancillary features of malignancy.

Gallbladder fossa nodularity in the liver as observed in alcoholic liver disease patients: Analysis based on hepatobiliary phase signal intensity on gadoxetate-enhanced MRI and extracellular volume fraction calculated from routine CT data

The purpose of this study is to further verify the concept utilizing signal intensity on hepatobiliary phase (HBP) of gadoxetate-enhanced MRI and extracellular volume fraction (ECV) calculated from CT data. Between Jan 2013 and September 2018, consecutive ALD patients who had both quadruple phase CT and gadoxetate-enhanced MRI within six months were retrospectively recruited. Those who had any intervention or disease involvement around gallbladder fossa were excluded. All images were reviewed and ECV was measured by two experienced radiologists. GBFN grades, and their HBP signal intensity or ECV relative to the surrounding background liver (BGL) were analyzed. There were 48 patients who met the inclusion criteria. There were GBFN grade 0/1/2/3 in 11/15/18/4 patients, respectively. The signal intensity on HBP relative to BGL were iso/slightly high/high in 30/15/3 patients, respectively, and ECV ratio (ECV of GBFN divided by that of BGL) was 0.88 ± 0.18, indicating there are more functioning hepatocytes and less fibrosis in GBFN than in BGL. The GBFN grades were significantly correlated to relative signal intensity at HBP (Spearman's rank correlation, p < 0.01, rho value 0.53), and ECV ratio (p < 0.01, rho value -0.45). Our results suggest GBFN in ALD would represent liver tissues with preserved liver function with less fibrosis, as compared to BGL, which are considered to support our hypothesis as shown above.

Wedge resection versus segment IVb and V resection of the liver for T2 gallbladder cancer: a systematic review and meta-analysis

Objectives

Although guidelines recommend extended cholecystectomy for T2 gallbladder cancer (GBC), the optimal hepatectomy strategy remains controversial. The study aims to compare the prognosis of T2 GBC patients who underwent wedge resection (WR) versus segment IVb and V resection (SR) of the liver.

Methods

A specific search of online databases was performed from May 2001 to February 2023. The postoperative efficacy outcomes were synthesized and meta-analyses were conducted.

Results

A total of 9 studies involving 2,086 (SR = 627, WR = 1,459) patients were included in the study. The primary outcomes included disease-free survival (DFS) and overall survival (OS). For DFS, the 1-year DFS was statistically higher in patients undergoing SR than WR [risk ratio (RR) = 1.07, 95% confidence interval (CI) = 1.02-1.13, P = 0.007]. The 3-year DFS (P = 0.95), 5-year DFS (P = 0.77), and hazard ratio (HR) of DFS (P = 0.72) were similar between the two groups. However, the 3-year OS was significantly lower in patients who underwent SR than WR [RR = 0.90, 95% CI = 0.82-0.99, P = 0.03]. Moreover, SR had a higher hazard HR of OS [HR = 1.33, 95% CI = 1.01-1.75, P = 0.04]. No significant difference was found in 1-year (P = 0.32) and 5-year (P = 0.9) OS. For secondary outcomes, patients who received SR tended to develop postoperative complications (POC) [RR = 1.90, 95% CI = 1.00-3.60, P = 0.05]. In addition, no significant differences in intrahepatic recurrence (P = 0.12) were observed.

Conclusions

In conclusion, SR can improve the prognosis of T2 GBC patients in DFS. In contrast to WR, the high HR and complications associated with SR cannot be neglected. Therefore, surgeons should evaluate the condition of the patients and take their surgical skills into account when selecting SR.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier, CRD42022362974.

Gallbladder fossa nodularity in the liver typically observed in patients with alcoholic liver disease; comparison with chronic hepatitis C patients

BACKGROUND AND PURPOSE

Gallbladder fossa nodularity (GBFN) is often observed in patients with alcoholic liver disease (ALD), and we hypothesized this may be due to the cholecystic venous drainage (CVD), sparing this area from portal perfusion containing alcohol absorbed in the alimentary tract, and also escaping from alcohol-induced fibrotic and atrophic change of the liver parenchyma. The purpose of this study is to verify our hypothesis, using chronic hepatitis C (CHC) patients as a control.

MATERIALS AND METHODS

Between 2013 and 2017, consecutive 45 ALD and 46 CHC patients who had contrast-enhanced CT were retrospectively recruited. Those who had interventions or disease involvement around gallbladder fossa were excluded. All CT images, and angiography-assisted CT(ang-CT) images , when available, were reviewed. GBFN was subjectively classified into grades 0-3, depending upon the conspicuity of nodularity, which was compared between the groups, and was also correlated to various clinicoradiological factors, including the alcohol consumption grades (ACG).

RESULTS

GBFN was more frequently observed in ALD than in CHC patients, and higher grade GBFN was associated with ALD rather than CHC (all p < 0.05). Multivariable analysis revealed independently significant factors related to GBFN grades were ACG and albumin-bilirubin grades. Ang-CT images were available in 11 patients, all of whom exhibited portal perfusion diminishment and faint arterial enhancement, suggesting CVD, at the region of GBFN. When GBFN grade 3 was considered to discriminate ALD from CHC, the value of sensitivity/specificity/accuracy is 9%/100%/55%.

CONCLUSION

GBFN may represent spared liver tissue from alcohol-containing portal venous perfusion due to CVD, which may serve as an adjunctive sign of ALD or alcohol overconsumption with high specificity, but low sensitivity.

Lesion or Pseudolesion? A Comprehensive Description of Perfusion-Based Liver Alterations on Contrast-Enhanced Computed Tomography and Literature Review

ABSTRACT

Pseudolesions on contrast-enhanced computed tomography represent a diagnostic challenge for radiologists because they could be difficult to distinguish from true space-occupying lesions. This article aims to provide a detailed overview of these entities based on radiological criteria (hyperattenuation or hypoattenuation, localization, morphology), as well as a brief review of the hepatic vascular anatomy and pathophysiological process. Relevant examples from hospital case series are reported as helpful hints to assist radiologists in recognizing and correctly diagnosing these abnormalities.

Portal venous gas accompanied by gallbladder torsion: a case report

Portal venous gas (PVG) generally suggests critically ill conditions such as severe bowel ischemia. We herein report a rare case of gallbladder torsion with PVG. An 88-year-old woman complained of right hypogastric pain. Ultrasonography (US) showed diffuse wall thickening of her gallbladder and mobile echogenic foci moving inside the portal venous branches. Computed tomography showed a thickened wall of the gallbladder with poor enhancement and tiny pockets of air in the portal venous branches (segments 4 and 5). There was no evidence of other visceral ischemia. She was diagnosed with necrotic cholecystitis and immediately underwent an emergency operation. We found a gangrenous gallbladder with 180° clockwise rotation along the longitudinal axis and performed cholecystectomy. We confirmed the disappearance of PVG with US after the operation. Her postoperative course was uneventful. Gallbladder diseases can produce PVG, and US might be a useful diagnostic modality to evaluate changes in PVG.

Hepatic pseudolesions caused by alterations in intrahepatic hemodynamics

Hepatic pseudolesion may occur in contrast-enhanced computed tomography and magnetic resonance imaging due to the unique haemodynamic characteristics of the liver. The concept of hepatic arterial buffer response (HABR) has become mainstream for the understanding of the mechanism of the reciprocal effect between hepatic arterial and portal venous flow. And HABR is thought to be significantly related to the occurrence of the abnormal imaging findings on arterial phase of contrast enhanced images, such as hepatic arterial-portal vein shunt and transient hepatic attenuation difference, which mimic hypervascular tumor and may cause clinical problems. Third inflow to the liver also cause hepatic pseudolesion, and some of the cases may show histopathologic change such as focal hyperplasia, focal fatty liver, and focal sparing of fatty liver, and called pseudotumor. To understand these phenomena might be valuable for interpreting the liver imaging findings.

Bi-segmentectomy versus wedge hepatic resection in extended cholecystectomy for T2 and T3 gallbladder cancer: A matched case-control study

Backgrounds/Aims

Extended cholecystectomy (EC) is the mainstay of treatment in most patients with potentially curable gallbladder cancer (GBC). The optimum extent of hepatic resection in EC is debatable.

Methods

This retrospective study was conducted on patients with GBC who received EC from May 2009 to February 2019. Based on the extent of hepatic resection, patients were divided into ECB (EC involving bi-segmentectomy s4b&5) and ECW (EC involving wedge hepatic resection) groups. Patients with T1 GBC, T4 GBC, and benign diseases were excluded. Post-exclusion, both groups were matched for T and N stage. Matched groups were then compared.

Results

Out of a total of 161 patients who received EC, 86 patients had ECB and 75 patients had ECW. After exclusion and matching, both ECB and ECW groups had 35 patients. Their demographic and clinical profiles were comparable. Surgical blood loss (p = 0.005) and postoperative complication rate (p = 0.035) were significantly less in the ECB group. For ECB vs. ECW, mean recurrence-free survival (RFS) was 58.2 months vs. 42.3 months (p = 0.264) and overall survival (OS) was 61.5 months vs. 43.4 months (p = 0.161). On univariate analysis, higher T and N stages were associated with poor prognosis. On multivariate analysis, higher T stage, N stage, and American Society of Anaesthesiologists grade were associated with poor RFS and OS.

Conclusions

The survival after ECB for T2 and T3 GBC was not significantly superior to that after ECW. However, surgical blood loss and postoperative complications were lower following ECB.

Survival Benefits of Simple Versus Extended Cholecystectomy and Lymphadenectomy for Patients With T2 Gallbladder Cancer: A Propensity-Matched Population-Based Study (2010 to 2015)

Objective

This article aims to evaluate the survival benefits of simple cholecystectomy, extended cholecystectomy, as well as scope regional lymphadenectomy for T2 gallbladder cancer (GBC) patients.

Methods

We identified eligible patients from the Surveillance, Epidemiology, and End Results database. The confounding factors were controlled via propensity score matching. The log-rank test was utilized to compare overall survival. The multivariate Cox regression was then used to determine risk factors.

Results

Overall, data from 1,009 patients were obtained. The median overall survival (OS) of 915 patients that underwent simple cholecystectomy was 15 months; the median OS of 94 patients that underwent extended cholecystectomy was 17 months. There were no significant differences before and after propensity score matching (p = 0.542 and p = 0.258). The patients who received regional lymphadenectomy did show significant survival benefit, compared to those who did not receive regional lymphadenectomy. Furthermore, this benefit is observed in the N0 stage, but not observed in the N1 stage. In addition, the OS of patients who received lymphadenectomy for four or more regions was significantly better than those who received one to three regions lymphadenectomy. Age, the scope of regional lymphadenectomy, N stage, and tumor size were identified as prognostic factors.

Conclusions

Extended cholecystectomy was not observed to significantly improve postoperative prognosis of patients with T2 GBC. However, there was a significant survival benefit shown for those with regional lymphadenectomy, particularly for patients with negative lymph nodes. Future studies on the control of potential confounding factors and longer follow-ups are still needed.

A case of resected hepatocellular carcinoma with gallbladder metastasis

Background

Advanced hepatocellular carcinoma (HCC) can often spread as intrahepatic metastases. Extrahepatic metastasis (e.g., lung, lymph nodes, and bones) is rare, and gallbladder metastasis from HCC is extremely rare.

Case presentation

A 66-year-old woman who presented with right hypochondrial pain was referred to our hospital for further examination of a liver tumor. The blood chemistry data showed elevated levels of serum α-fetoprotein (AFP) (3730 ng/mL), protein induced by vitamin K absence or antagonist II (PIVKA-II) (130 mAU/mL), and carcinoembryonic antigen (CEA) (358.6 ng/mL). Hepatitis B surface antigen and hepatitis C virus antibody were negative. Dynamic computed tomography (CT) showed a tumor measuring 12 × 7 cm in the right lobe of the liver. This tumor was contrast-enhanced in the hepatic arterial phase and then became less dense than the liver parenchyma in the portal phase. A well-enhanced tumor was found in the gallbladder. No regional lymph nodes were enlarged. Contrast-enhanced magnetic resonance imaging (MRI) demonstrated that the liver tumor showed a pattern of early enhancement and washout. The gallbladder tumor was also detected as an enhanced mass. Endoscopic retrograde cholangiography (ERC) showed compression of the left hepatic duct due to the liver tumor. The patient was diagnosed with simultaneous HCC and gallbladder cancer. Right hepatic trisectionectomy and caudate lobectomy with extrahepatic bile duct resection were performed. Histopathological examination of the resected liver specimen showed a poorly differentiated HCC cell component with a trabecular and solid growth, and diffuse invasion of the portal vein. The same tumor cells were found in the gallbladder, but no continuity with the liver tumor was identified. Immunohistochemistry of the liver tumor and gallbladder was positive for AFP, Glypican 3, and CK7, and negative for CK19. The final pathological diagnosis was the gallbladder metastasis from HCC. A follow-up diagnostic image 33 months after surgery showed a mass in the upper lobe of the left lung. The patient underwent left upper lobectomy. Postoperative pathology revealed that the lung lesion was a metastasis of HCC. The patient was still alive with lung metastasis and was being treated with a molecular-targeting drug in good health 42 months after the initial surgery.

Conclusions

The standard treatment for advanced HCC with extrahepatic metastases is molecularly targeted drugs, but surgery is also an option if the lesion can be resected en bloc without remnants.

An intact boundary between the tumor and inner hypoechoic layer discriminates T1 lesions among sessile elevated gallbladder cancers

BACKGROUND

The depth of invasion determines the surgical method for treating gallbladder cancer (GBC). However, the preoperative correct diagnosis of invasion depth, especially discrimination of T1 lesions among sessile elevated GBCs, is difficult. We investigated the utility of preoperative endoscopic ultrasound (EUS) findings for diagnosing the invasion depth.

METHODS

We studied a sessile elevated GBC specimen diagnosed as a T1 lesion before developing our study protocol. EUS evidenced an intact boundary between the tumor and the inner hypoechoic layer (the intact boundary sign). To evaluate the potential of using this sign to diagnose T1 GBC as a primary outcome indicator, we retrospectively analyzed patients who underwent surgical resection of sessile elevated GBCs between April 2009 and March 2020.

RESULTS

Of the 26 surgically resected sessile elevated GBC specimens, 20 were included and six were excluded due to difficulty in evaluating the overall tumor or layer structure. The Kappa coefficient for interobserver agreement regarding the intact boundary sign was 0.733. The sensitivity and specificity of the sign for diagnosing T1 lesions were 0.857 and 1.000, respectively.

CONCLUSION

This new EUS finding could guide the accurate diagnosis of T1 lesions in patients with sessile elevated GBC.

Vascular disorders of the gallbladder and bile ducts: Imaging findings

Vascular disorders of the gallbladder and biliary tree are many and varied. In the acute setting, the clinical presentation of vascular conditions such as hemorrhagic cholecystitis and gangrenous cholecystitis are non-specific and rely on imaging for diagnosis and triaging for emergent surgery. These hemorrhagic and ischemic complications of acute cholecystitis are uncommon but potentially fatal. Hemorrhage into the gallbladder and biliary tree, from other causes, may itself result in acute cholecystitis. Knowledge of vascular anatomy of the gallbladder and biliary tree is essential for surgeons to prevent significant operative bleeding complications, particularly in laparoscopic cholecystectomy. The unique venous drainage of the gallbladder and biliary tree, with their connections to the portal venous system, lends itself to less well-recognised vascular phenomena such as gallbladder varices, portal biliopathy, and gallbladder bed perfusion abnormalities.

Clinical practice guidelines for the management of biliary tract cancers 2019: The 3rd English edition

BACKGROUND

The Japanese Society of Hepato-Biliary-Pancreatic Surgery launched the clinical practice guidelines for the management of biliary tract cancers (cholangiocarcinoma, gallbladder cancer, and ampullary cancer) in 2007, then published the 2nd version in 2014.

METHODS

In this 3rd version, clinical questions (CQs) were proposed on six topics. The recommendation, grade for recommendation, and statement for each CQ were discussed and finalized by an evidence-based approach. Recommendations were graded as Grade 1 (strong) or Grade 2 (weak) according to the concepts of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system.

RESULTS

The 31 CQs covered the six topics: (a) prophylactic treatment, (b) diagnosis, (c) biliary drainage, (d) surgical treatment, (e) chemotherapy, and (f) radiation therapy. In the 31 CQs, 14 recommendations were rated strong and 14 recommendations weak. The remaining three CQs had no recommendation. Each CQ includes a statement of how the recommendations were graded.

CONCLUSIONS

This latest guideline provides recommendations for important clinical aspects based on evidence. Future collaboration with the cancer registry will be key for assessing the guidelines and establishing new evidence.

Improvement in the diagnosis and treatment of T2 gallbladder carcinoma is pivotal to improvement in the overall prognosis for this disease

Since the American Joint Committee on Cancer (AJCC) subdivided the T2 stage of gallbladder carcinoma (GBC) into T2a and T2b, the diagnosis and treatment of those stages have been a subject of heated discussion and controversy. T2 is a stage of GBC that might be treatable. Based on the extent of lymph node metastasis and distant metastasis, T2 GBC can be classified into various pathological stages such as IIA, IIB, IIIB, and IVB, leading to controversy in clinical settings. This review aims to discuss the effectiveness of and controversies concerning S4b+5 resection, the acceptable extent of lymph node dissection, the timing for treatment of incidental gallbladder cancer, and adjuvant therapy. This review also aims to suggest directions for and recommendations regarding clinical research in the future.

Spectrum of Pitfalls, Pseudolesions, and Misdiagnoses in Noncirrhotic Liver

OBJECTIVE

The purpose of this article is to illustrate the various pitfalls, mimics, and atypical features that can lead to inaccurate diagnosis of focal lesions in a noncirrhotic liver. The content includes relevant pathogenesis and background as well as specific clues that can be used to reach an accurate diagnosis.

CONCLUSION

When assessing focal hepatic lesions, it is important to avoid pitfalls and misdiagnoses that can alter the management plan. Helpful strategies for avoiding pitfalls include paying close attention to the clinical history of the patient, carefully evaluating all of the available imaging studies, and being aware of the various radiologic mimics.

Quantitative contrast-enhanced US helps differentiating neoplastic vs non-neoplastic gallbladder polyps

OBJECTIVES

To differentiate between large (≥ 1 cm in diameter) gallbladder (GB) non-neoplastic and neoplastic polyps using quantitative analysis of contrast-enhanced ultrasound (CEUS) findings.

METHODS

From September 2017 to May 2018, 29 patients (10 males; median age, 63 years) with GB polyps of ≥ 1 cm in diameter who were undergoing cholecystectomy were consecutively enrolled. All patients underwent preoperative conventional US and CEUS examinations. Quantitative analysis of CEUS findings using time-intensity curves between the two groups was independently performed by two radiologists. The interobserver agreement for the quantitative analysis of the CEUS results was measured using the intraclass correlation coefficient. Receiver operating characteristic analysis was performed to evaluate the diagnostic performance of CEUS examination.

RESULTS

After the cholecystectomy, the patients were classified into the non-neoplastic polyp group (n = 12) and the neoplastic polyp group (n = 17) according to the pathological results. The interobserver agreement for quantitative assessment between the two radiologists was near perfect to substantial. Quantitative assessment of the CEUS findings revealed that the rise time, mean transit time, time to peak, and fall time of non-neoplastic GB polyps were significantly shorter than those of neoplastic polyps (p < 0.001, p = 0.008, p = 0.013, and p = 0.002, respectively). The sensitivity and specificity of the quantitative CEUS parameters for the differentiation between the two groups were 76.5-100% and 75%, respectively, with an area under the curve of 0.765-0.887.

CONCLUSIONS

Quantitative analysis of CEUS findings could be valuable in differentiating GB neoplastic polyps from non-neoplastic polyps.

KEY POINTS

• Quantitative analysis of CEUS findings could be valuable in differentiating gallbladder neoplastic polyps from non-neoplastic polyps. • Quantitative analysis of CEUS findings in gallbladder polyps provides cut-off values for differentiation between neoplastic polyps and non-neoplastic polyps with near-perfect to substantial interobserver agreement.

Validation of the oncologic effect of hepatic resection for T2 gallbladder cancer: a retrospective study

BACKGROUND

While extended cholecystectomy is recommended for T2 gallbladder cancer (GBC), the role of hepatic resection for T2 GBC is unclear. This study aimed to identify the necessity of hepatic resection in patients with T2 GBC.

METHODS

Data of 81 patients with histopathologically proven T2 GBC who underwent surgical resection between January 1999 and December 2017 were enrolled from a retrospective database. Of these, 36 patients had peritoneal-side (T2a) tumors and 45 had hepatic-side (T2b) tumors. To identify the optimal surgical management method, T2 GBC patients were classified into the hepatic resection group (n = 44, T2a/T2b = 20/24) and non-hepatic resection group (n = 37, T2a/T2b = 16/21). The recurrence pattern and role of hepatic resection for T2 GBC were then investigated.

RESULTS

Mean age of the patients was 69 (range 36-88) years, and the male-to-female ratio was 42:39 (male, 51.9%; female, 48.1%). Hepatic-side GBC had a higher rate of recurrence than peritoneal-side GBC (44.4% vs. 8.3%, p = 0.006). The most common type of recurrence in T2a GBC was para-aortic lymph node recurrence (n = 2, 5.6%); the most common types of recurrence in T2b GBC were para-aortic lymph node recurrence (n = 7, 15.6%) and intrahepatic metastasis (n = 6, 13.3%). Hepatic-side GBC patients had worse survival outcomes than peritoneal-side GBC patients (76.0% vs. 96.6%, p = 0.041). Hepatic resection had no significant treatment effect in T2 GBC patients (p = 0.272). Multivariate analysis showed that lymph node metastasis was the only significant prognostic factor (p = 0.002).

CONCLUSIONS

Hepatic resection is not essential for curative treatment in T2 GBC, and more systemic treatments are needed for GBC patients, particularly for those with T2b GBC.

Cholecystic Venous Anatomy: A Cadaveric Study with Implications for Portal Venous Interruption Procedure

The techniques of portal vein embolization (PVE) or ligation (PVL) have the goals of combining an induced atrophy of metastatic segments with the rapid relative compensatory hypertrophy of the postresection future liver remnant (FLR). Our study examines the anatomy of right-left hepatic lobar venous connections in the adult cadaver using corrosion cast analysis in an effort to define some of the inherent anatomical reasons why both PVL and PVE may be technically unsuccessful. Corrosion cast models of 215 cadaveric liver specimens were evaluated for hepatopetal venous blood flow, with a particular emphasis on cholecystic venous drainage patterns, including 57 cases prepared after lobar portal venous ligation. In 88.8 per cent of corrosion casts, there was a segmental venous communication between the gallbladder and all segments of the liver, except segment II. There was cystic vein drainage directly into a main lobar branch or directly into the portal vein itself in 11.2 per cent of cases. In all 57 cases, after portal lobar venous division, in situ cystic veins allowed persistent venous communication between lobes. Our cadaveric corrosion cast study has suggested that there is extensive intrahepatic cholecystic venous drainage to many segments of the liver. Perfusion from the gallbladder may potentially contribute to a limited response to procedures which interrupt the portal venous flow and could affect their capacity to induce an adequate FLR which would permit a wider hepatectomy.

The utility of hepatic artery velocity in diagnosing patients with acute cholecystitis

PURPOSE

To test the diagnostic performance of elevated peak systolic hepatic arterial velocity (HAv) in the diagnosis of acute cholecystitis.

METHODS

229 patients with an ultrasound (US) performed for right upper quadrant (RUQ) pain were retrospectively reviewed. 35 had cholecystectomy within 10 days of ultrasound and were included as test subjects. 47 had normal US and serology and were included as controls. Each test patient US was reviewed for the presence of gallstones, gallbladder distention, sludge, echogenic pericholecystic fat, pericholecystic fluid, gallbladder wall thickening, gallbladder wall hyperemia, and reported sonographic Murphy sign. Demographic, clinical, and hepatic artery parameters at time of original imaging were recorded. Acute cholecystitis at pathology was the primary outcome variable.

RESULTS

21 patients had acute cholecystitis and 14 had chronic cholecystitis by pathology. For patients who went to cholecystectomy, HAv ≥100 cm/s to diagnose acute cholecystitis was more accurate (69%) than the original radiology report (63%), the presence of gallstones (51%), and sonographic Murphy sign (50%). Statistically significant predictors of acute cholecystitis included HAv ≥100 cm/s (p = 0.008), older age (p = 0.012), and elevated WBC (p = 0.002), while gallstones (p = 0.077), hepatic artery resistive index (HARI) (p = 0.199), gallbladder distension (p = 0.252), sludge (p = 0.147), echogenic fat (p = 0.184), pericholecystic fluid (p = 0.357), wall thickening (p = 0.434), hyperemia (p = 0.999), and sonographic Murphy sign (p = 0.765) were not significantly correlated with acute cholecystitis compared to chronic cholecystitis.

CONCLUSION

HAv ≥100 cm/s is a useful objective parameter that may improve the performance of US in the diagnosis of acute cholecystitis.

The optimal surgical resection approach for T2 gallbladder carcinoma: evaluating the role of surgical extent according to the tumor location

Purpose

The clinical behavior of T2 gallbladder cancer varies among patients. The aims of this study were to identify prognostic factors for survival and recurrence, and to determine the optimal surgical strategy for T2 gallbladder cancer.

Methods

We conducted a retrospective analysis of 78 patients with T2 gallbladder cancer who underwent surgical resection for gallbladder cancer.

Results

Twenty-eight patients (35.9%) underwent simple cholecystectomy and 50 (64.1%) underwent extended cholecystectomy. Among 56 patients without LN metastasis (n = 20) or unknown LN status (no LN dissection, n = 36), the 5-year disease-free survival rates were 81.6%, and 69.8% (P = 0.080). In an analysis according to tumor location, patients with tumors located on the hepatic side (n = 36) had a higher recurrence rate than patients with tumors located on the peritoneal side only (n = 35) (P = 0.043). On multivariate analysis, R1 resection and lymph node metastasis were significant, independent prognostic factors for poor disease-free and overall survival.

Conclusion

R0 resection and LN dissection are an appropriate curative surgical strategy in patients with T2 gallbladder cancer. Tumors located on the hepatic side show worse prognosis than tumors located on the peritoneal side only, hepatic resection should be considered.

Imaging of aberrant left gastric vein and associated pseudolesions of segments II and III of the liver and mimickers

We present imaging findings of aberrant left gastric vein (ALGV) and associated pseudolesions and mimickers including metastases and focal nodular hyperplasia. ALGV is formed due to interrupted involution of anastomotic omental veins, and it can drain into left portal vein or segments II and III of the liver as third inflow. Focal fat, focal fat sparing, and perfusion changes can be seen due to the presence of ALGV, which can mimic metastasis in cancer patients. ALGV may also serve as a pathway for direct tumor spread into the liver in patients with gastric cancer. Magnetic resonance imaging can be used as a problem solving tool in the presence of equivocal findings on ultrasonography and computed tomography.

Pseudolesion in segment IV A of the liver from vein of Sappey secondary to SVC obstruction

Pseudolesions in the liver are caused by unusual/altered hemodynamics of the liver and can be confused with a true hepatic mass. In superior vena cava (SVC) obstruction. there is recruitment of the cavo-mammary-phrenic-hepatic-capsule-portal pathway. and the venous blood follows the internal mammary vein, the inferior phrenic vein, the hepatic capsule veins, and the intrahepatic portal system. causing a hypervascular pseudolesion in segment IV A of the liver. Recognizing the classic appearances of this hypervascular pseudolesion from the vein of Sappey in a CT study of the abdomen has prognostic implications in directing further evaluation of the chest for SVC obstruction. We present a case of a 54-year-old HIV-positive male smoker in whom identification of the hypervascular pseudolesion from the vein of Sappey on the abdominal CT led to the diagnosis of SVC syndrome.

Gallbladder bed resection or hepatectomy of segments 4a and 5 for pT2 gallbladder carcinoma: analysis of Japanese registration cases by the study group for biliary surgery of the Japanese Society of Hepato-Biliary-Pancreatic Surgery

PURPOSE

Hepatectomy of segments 4a and 5 (S4a+5) is the recommended treatment for pT2 gallbladder cancer. However, gallbladder bed resection is also occasionally used. Using nationwide data from the Japanese Biliary Tract Cancer Registry and a questionnaire survey, we retrospectively compared these 2 methods of treatment.

METHOD

The study involved 85 patients with pT2, pN0 gallbladder cancer (55 treated with gallbladder bed resection, and 30, with S4a+5 hepatectomy). The prognosis and mode of tumor recurrence following treatment were analyzed retrospectively, with overall survival as the endpoint.

RESULTS

The 5-year survival rate did not differ significantly between the 2 groups. Univariate analysis showed that bile duct resection and perineural tumor invasion were significant prognostic factors, but the extent of hepatectomy, location of the major intramural tumor, regional lymph node excision, and histological type were not. Multivariate analysis identified perineural tumor invasion as a significant prognostic factor. Recurrence occurred most frequently in both lobes than S4a+5 of the liver following gallbladder bed resection.

CONCLUSION

In the present study of cases of Japanese Biliary Tract Cancer Registry, it was not possible to conclude that S4a+5 hepatectomy was superior to gallbladder bed resection.

Fatal intra-abdominal hemorrhage as a result of avulsion of the gallbladder: a postmortem case report

Gallbladder injuries are extremely rare in blunt trauma, with a reported incidence of <2%. We report an autopsy case of fatal hemorrhagic shock due to intra-abdominal bleeding resulting from complete avulsion of the gallbladder associated with liver cirrhosis. Multiplanar images derived from multislice computed tomography (MSCT) performed as part of pre-autopsy screening showed complete avulsion of the gallbladder without any other associated intra-abdominal injuries, facilitating forensic autopsy planning. In this report, we discuss the role of MSCT in cases of fatal intra-abdominal bleeding caused by avulsion of the gallbladder and discuss the mechanism of this injury.

Falciform ligament abscess from left sided portal pyaemia following malignant obstructive cholangitis

Abscess formation of the falciform ligament is incredibly rare and perplexing when encountered for the first time. It is reported to occur in the setting of cholecystitis and cholangitis, but the pathophysiology is poorly understood.

In this case report, we present a 73-year-old man with falciform ligament abscess following cholangitis from an obstructive ampullary carcinoma. The patient was referred to the Royal Adelaide Hospital from a country hospital, with progressive jaundice, anorexia and nausea. Prior to transfer, he deteriorated with cholangitis, dehydration and renal failure. On arrival, his abdomen was exquisitely tender along the course of the falciform ligament. His blood tests revealed an elevated white cell count of 14.9 x 10³/μl, bilirubin of 291μmol/l and creatinine of 347 μmol/l. His CA 19-9 was markedly elevated at 35,000 kU/l. A non-contrast computed tomography (CT) demonstrated gross biliary dilatation and a collection tracking along the path of the falciform ligament to the umbilicus.

The patient was commenced on intravenous antibiotics and underwent an urgent endoscopic retrograde cholangiopancreatogram (ERCP) with sphincterotomy and biliary stent drainage. Cholangiogram revealed a grossly dilated biliary tree, with abrupt transition at the ampulla, which on biopsy confirmed an obstructing ampullary carcinoma. Following ERCP, his jaundice and abdominal tenderness resolved. He was optimized over 4 weeks for an elective pancreaticoduodenectomy.

At operation, we found abscess transformation of the falciform ligament. Copious amounts of pus and necrotic material was drained. Part of the round ligament was resected along the undersurface of the liver. Histology showed that there was prominent histiocytic inflammation with granular acellular eosinophilic components. The patient recovered slowly but uneventfully.

A contrast CT scan undertaken 2 weeks post-operatively (approximately 7 weeks after the initial CT) revealed left portal venous thrombosis, which was likely to be a delayed discovery and was managed conservatively.

We present this patient’s operative images and radiographic findings, which may explain the pathophysiology behind this rare complication. We hypothesize that cholangitis, with secondary portal pyaemia and tracking via the paraumbilical veins, can cause infectious seeding of the falciform ligament, with consequent abscess formation.

Diffuse gallbladder wall thickening on computed tomography in patients with liver cirrhosis: correlation with clinical and laboratory variables

OBJECTIVES

The objective of the study was to retrospectively evaluate (a) which clinical/laboratory features are associated with the presence of diffuse gallbladder wall thickening (DGWT) in cirrhotic patients and (b) whether the degree of DGWT is correlated with such clinical/laboratory variables.

METHODS

After excluding patients with DGWT or laboratory test abnormalities from known causes unrelated to liver cirrhosis, a retrospective review of liver computed tomography obtained from 242 consecutive cirrhotic patients was performed by 2 radiologists in consensus to determine the presence of DGWT of greater than 3 mm in thickness and, if present, to measure the degree of DGWT defined as maximal thickness. Univariate and multivariate analysis were performed to evaluate association between presence/degree of DGWT and clinical/laboratory features.

RESULTS

Of 242 patients, 73 (30.2%) had DGWT. Diffuse gallbladder wall thickening was seen in 7.6% (12/157) of patients with Child-Pugh class A, 61.1% (33/54) of class B, and 90.3% (28/31) of class C (P < 0.001). The presence of ascites, lower platelet count, and lower albumin level were independently associated with the presence of DGWT (P < 0.01, P = 0.01, and P = 0.02, respectively). However, these factors did not show significant correlation with the degree of DGWT.

CONCLUSIONS

The presence of DGWT in cirrhotic patients is associated with the presence of ascites, lower platelet count, and lower albumin level. The degree of DGWT is not correlated with such variables.

Incidentally-discovered gallbladder cancer: When, why and which reoperation?

Cancer of the gallbladder, a rare entity with a poor prognosis, is often discovered incidentally during or after cholecystectomy. It tends to disseminate early via lymphatic, peritoneal, endobiliary, and hematogenous pathways. Diagnosis is made intra-operatively in only a quarter of cases, by examination of the opened cholecystectomy specimen in the operating room by the surgeon; this procedure should be routine. For incidentally-discovered cancers, survival was 28% at five years. Prognostic factors include age, TNM stage, gallbladder perforation during cholecystectomy and less-than-optimal resection at re-operation. Whether the laparoscopic route for the initial cholecystectomy has an impact on survival remains a subject of debate. R0 surgery is the only potentially curative treatment: simple cholecystectomy with clear margins is adequate resection for stage T1a tumors; extended cholecystectomy with lymphadenectomy and possibly resection of the bile duct is required for more advanced stages. After curative resection, neo-adjuvant or adjuvant chemotherapy and radiotherapy have not, so far, proven effective. Improvement of surgical practices (systematic review of cholecystectomy specimens in the OR, prevention of gallbladder perforation with bile spillage during surgery, early re-intervention for optimal resection) could improve the prognosis of these cancers.

Isolated metastasis to the gallbladder from hepatocellular carcinoma

AIM

Metastasis to gallbladder (GB) from hepatocellular carcinoma (HCC) is rare, and it is difficult to determine indications for surgery. We report eight cases of synchronous isolated GB metastasis, and analyze their features retrospectively.

METHODS

Among 439 HCC patients who underwent hepatectomy from 1998 to 2008 at our institution, 393 (89.5%) underwent concurrent cholecystectomy.

RESULTS

Among them, eight (1.8%) had GB metastasis without other distant metastases. None of these cases showed evidence of direct invasion. All cases had advanced portal vein thrombus (PVTT) and their main tumor located near the GB bed. Five cases had apparent tumor mass in the GB wall, and the other three cases had only tumor thrombus in the GB veins. Six cases were treated postoperatively with local infusion therapy with interferon, and three of them showed long-term survival.

CONCLUSION

Our eight cases of GB metastasis from HCC were closely related to PVTT. Surgical resection and multimodal treatment would be necessary for long-term survival in cases with isolated GB metastasis.

Evaluation of cholecystic venous flow using indocyanine green fluorescence angiography

BACKGROUND/PURPOSE

The cholecystic veins are thought to be an important metastatic route of gallbladder carcinoma to the liver. In the present study we evaluated the cholecystic venous drainage area, utilizing a novel method, indocyanine green (ICG) fluorescence angiography after superselective catheterization of the cholecystic artery, to detect and elucidate cholecystic venous flow.

METHODS

Cannulation of the cholecystic artery was performed under laparotomy in nine patients who required a cholecystectomy. After ICG injection into the cholecystic artery, the cholecystic venous flow images were visualized with a near-infrared camera system and were analyzed according to site, shape, and time of fluorescence.

RESULTS

Fluorescence images of the cholecystic venous flow could be viewed as real-time images in all patients. We demonstrated that the route of the cholecystic venous flow could be classified into two patterns: type 1, in which the cholecystic veins flowed directly into the hepatic parenchyma adjacent to the gallbladder; and type 2, in which the veins flowed into sites separate from the gallbladder. In the type 1 pattern, fluorescence was observed in segment (S; defined according to Couinaud's nomenclature) 4a or S5 adjacent to the gallbladder in all cases. On the other hand, in the type-2 pattern, fluorescence was observed in S4a (6/9), S5 (8/9), S4b (2/9), S3 (2/9), S1 (1/9), S2 (1/9), and S8 (1/9) distant from the gallbladder. Overall, two-thirds of the cases showed fluorescence in segments other than S4a or S5.

CONCLUSIONS

Indocyanine green (ICG) fluorescence angiography is considered to be a useful method to detect and elucidate cholecystic venous flow in real time. This study showed that the cholecystic venous flow spread to the liver through two different pathways, one that flowed directly into the hepatic parenchyma adjacent to the gallbladder, while the other flowed into sites separate from the gallbladder. Taking these findings into consideration, we may therefore need to reconsider the preventive effects of a hepatic resection.

Postgastrectomy development or accentuation of focal fatty change in segment IV of the liver: correlation with the presence of aberrant venous branches of the parabiliary venous plexus

BACKGROUND

Focal fatty change in segment IV (S4) of the liver is occasionally a diagnostic dilemma in the postoperative follow-up of gastric cancer patients.

GOAL

To determine whether development of focal fatty change in S4 is related to the presence of aberrant venous branches of the parabiliary venous plexus (PBP).

STUDY

Two hundred seventy-six patients with gastrectomy who had been imaged by thin-slice preoperative computed tomography (CT) and at least one postoperative CT, and had no apparent liver masses were retrospectively analyzed. Preoperative CT were evaluated for the presence of aberrant venous branches of PBP entering S4. Serial postoperative CTs were evaluated for any interval change in the appearance of S4 of the liver.

RESULTS

There were 6 patients out of 276 (2%) in whom focal fatty liver developed or accentuated after the surgery. In 5 out of the 6, preoperative CT demonstrated aberrant branches of PBP; 3 of these were suggested to be aberrant right gastric veins, and the etiologies were not determined in 2. In 1 case, no definite aberrant vessel was seen. Aberrant vessels were found in none of the remaining 270 patients. The incidence of aberrant vessels was significantly higher in patients who developed postoperative radiologic change in S4 than in those who did not (P<0.0001).

CONCLUSIONS

Development or accentuation of focal fatty liver in S4 of the liver was observed in 2% of postgastrectomy patients and was closely related to the presence of aberrant venous branches of PBP.

The incidence of hepatic pseudolesions caused by focal rib compression as seen on multidetector row CT in patients of different hepatic function

OBJECTIVE

To determine whether the incidence of pseudolesions of the liver caused by rib compression is correlated with liver function.

MATERIALS AND METHODS

Multidetector row CT images of 150 consecutive cases were evaluated for the presence of pseudolesions caused by rib compression. Liver function was categorized into two groups mainly using the Child-Pugh classification: Group I-normal liver function and Grade A; Group II-Grades B and C. The number of focal deformities of the liver caused by rib compression was also counted. The incidence of pseudolesions based on number of patients or focal deformities of liver parenchyma by rib compression were compared between the two groups.

RESULTS

There were 108 and 42 patients in Groups I and II, respectively. 169 and 41 focal deformities of the liver caused by rib compression were found in Groups I and II, respectively. Patient-based and deformity-based incidences of pseudolesions were 10.7% (16/150) and 7.6% (16/210), respectively. All pseudolesions were seen in patients of Group I. Both patient-based and deformity-based incidences of pseudolesions were significantly higher in Group I as compared with those in Group II.

CONCLUSION

Pseudolesions of the liver caused by focal rib compression may be seen more frequently in patients with preserved liver function than in those with impaired function.

Portal flow into the liver through veins at the site of biliary-enteric anastomosis

The aim of this study was to establish the role played by jejunal veins in hepatopetal flow after biliary-enteric anastomosis and to evaluate the helical CT features of hepatopetal flow through the anastomosis. We retrospectively analyzed helical CT images of the liver in 31 patients with biliary-enteric anastomosis who underwent hepatic angiography with (n=13) or without (n=18) CT arterial portography within 2 weeks of the CT examination during the last 4 years. Arterial portography showed hepatopetal flow through small vessels located (communicating veins) between the elevated jejunal veins and the intrahepatic portal branches in two (9%) of 22 patients with a normal portal system. Helical CT showed focal parenchymal enhancement around the anastomosis in these two patients. All nine patients with extrahepatic portal vein occlusion (100%) had hepatopetal flow through the anastomosis, and four of the nine had decreased portal flow. CT revealed small communicating veins in two of these four patients. In five patients with normal portal perfusion despite extrahepatic portal vein occlusion, CT detected dilated communicating veins and elevated jejunal veins. The presence of communicating veins and/or focal parenchymal enhancement around the anastomosis indicates hepatopetal flow through the elevated jejunal veins.

Metastasis of primary gallbladder carcinoma in lymph node and liver

AIM: To evaluate the patterns with metastasis of gallbladder carcinoma in lymph nodes and liver.

METHODS: A total of 45 patients who had radical surgery were selected. The patterns with metastasis of primary gallbladder carcinoma in lymph nodes and liver were examined histopathologically and classified as TNM staging of the American Joint Committee on Cancer.

RESULTS: Of the 45 patients, 29 (64.4%) had a lymph node positive disease and 20 (44.4%) had a direct invasion of the liver. The frequency of involvement of lymph nodes was strongly influenced by the depth of the primary tumor (P = 0.0001). The postoperative survival rate of patients with negative lymph node metastasis was significantly higher than that of patients with positive lymph node metastasis (P = 0.004), but the postoperative survival rate of patients with N1 lymph node metastasis was not significantly different from that of patients with N2 lymph node metastasis (P = 0.3874). The postoperative survival rate of patients without hepatic invasion was significantly better than that of patients with hepatic invasion (P = 0.0177).

CONCLUSION: Complete resection of the regional lymph nodes is important in advanced primary gallbladder carcinoma (PGC). The initial sites of liver spread are located mostly in segments IV and V. It is necessary to achieve negative surgical margins 2 cm from the tumor. In patients with hepatic hilum invasion, extended right hepatectomy with or without bile duct resection or portal vein resection is necessary for curative resection.

Early-enhancing nonneoplastic lesions on gadolinium-enhanced magnetic resonance imaging of the liver following partial hepatectomy

PURPOSE

To assess the frequency, imaging findings, and significance of early-enhancing nonneoplastic (EN) lesions with gadolinium-enhanced magnetic resonance imaging (MRI) of the liver following partial hepatectomy.

MATERIALS AND METHODS

We retrospectively reviewed MR images after partial hepatectomy in 30 patients. Postoperative MRI was performed in 1-12 months (mean, 3.7 months) after partial hepatectomy. We defined the EN lesion as a lesion that was ill defined; irregular, wedge shaped, or serpiginous; located along the liver edge; not visible on unenhanced MR images; did not appear hypointense on portal venous- or equilibrium-phase images; or a combination of those imaging findings.

RESULTS

A total of 39 EN lesions (size range, 5-60 mm; mean, 25.2 mm) in 19 patients and 17 recurrent tumors (size range, 5-50 mm; mean, 16.8 mm) in 10 patients newly appeared after partial hepatectomy. The EN lesions were diagnosed as pseudolesions by the second postoperative follow-up MRI in 17 patients or contrast-enhanced computed tomography (CT) in two. A total of 13 EN lesions (33%) were located along the liver edge and 20 (51%) were adjacent to the resected area. The shape was circular in 11 (28%), oval in three (8%), irregular in 11 (28%), wedge shaped in five (13%), and serpiginous in nine (23%). No EN lesion showed hypointensity on gadolinium-enhanced portal venous-phase or equilibrium-phase images. A total of 14 EN lesions (36%) showed slight hyperintensity on T2-weighted images. The confidence levels for malignancy probability assigned by blinded radiologists were lower with EN lesions than with recurrent tumors (P < 0.001).

CONCLUSION

EN lesions are frequently seen in MRI following partial hepatectomy, and occasionally are slightly hyperintense on T2-weighted images, mimicking malignant tumors. However, most EN lesions can be correctly diagnosed with MRI findings.

Intrahepatic arterioportal shunting and anomalous venous drainage: understanding the CT features in the liver

The increased use of high-contrast volume, arterial-phase studies of the liver has demonstrated the frequent occurrence of arterioportal shunts within both the cirrhotic and non-cirrhotic liver. This article sets out to explain the underlying microcirculatory mechanisms behind these commonly encountered altered perfusion states. Similarly, well-recognised portal perfusion defects occur around the perifalciform and perihilar liver and are largely caused by anomalous venous drainage via the paraumbilical and parabiliary venous systems. The underlying anatomy will be discussed and illustrated. These vascular anomalies are all caused by or result in diminished portal perfusion and are often manifest in the setting of portal venous thrombosis. The evolving concept of zonal re-perfusion following portal vein thrombosis will be discussed.

Early-enhancing Non-neoplastic Lesions on Gadolinium-enhanced MRI of the Liver

AIM

To assess the frequency, cause, and significance of early-enhancing, non-neoplastic (EN) lesions on gadolinium-enhanced magnetic resonance imaging (MRI) of the liver performed for the detection of malignant hepatic tumours.

MATERIALS AND METHODS

From September 1997 to September 2000, we reviewed the images of 125 patients, suspected of having hepatic tumours, in whom (1) gadolinium-enhanced triphasic dynamic gradient-recalled-echo (GRE) imaging in addition to unenhanced T1- and T2-weighted MRI was performed, (2) conventional angiography and combination computed tomography (CT) hepatic arteriography and CT during arterial portography were performed within 2 weeks of the MRI, and (3) definitive surgery within 2 weeks of the MRI or follow-up study by means of intravenously contrast-enhanced CT or MRI in 10 months or more was performed. Angiographic studies were correlated to determine the underlying causes of the EN lesions.

RESULTS

We found 78 EN lesions in 36 patients (29%), ranging in size from 4 and 50 mm (mean, 12.2 mm). From the MR reports, our radiologists had prospectively diagnosed EN lesions as probable malignant tumours in eight (10%), possible malignant tumours in 36 (46%), and probable non-neoplastic lesion in 34 (44%). EN lesions were found in 27 of 81 (33%) cirrhotic patients and in nine of 44 (20%) non-cirrhotic patients. Fifty-one EN lesions (65%) were located along the liver edge. The shape was circular in 42 (54%), oval in 14 (18%), irregular in 12 (15%), wedge-shaped in seven (9%), and fan-shaped in three (4%). Twenty EN lesions (26%) appeared slightly hyperintense on T2-weighted images. The causes were non-neoplastic arterio-portal shunting in 48 (62%), cystic venous drainage in four (5%), rib compression in four (5%), aberrant right gastric venous drainage in two (3%), and unknown in 20 (26%).

CONCLUSION

Over half the number of EN lesions were caused by non-neoplastic arterio-portal shunting, occasionally showing slight hyperintensity on T2-weighted images. On MR images the non-neoplastic nature of the EN lesion was often ascertained. Radiologists should not overcall EN lesions as malignant as the patients involved would be inappropriately considered inoperable. In problematic cases, further investigation with angiographic CT or follow-up imaging studies should be performed.

Effects of prostaglandin E(1) injection through the superior mesenteric artery on the hemodynamics of hepatocellular carcinoma

OBJECTIVE

The purpose of our study was to assess the effects of portal blood flow on contrast enhancement in hepatocellular carcinoma lesions on CT hepatic arteriography.

SUBJECTS AND METHODS

We examined 43 tumors in 39 patients who simultaneously underwent CT during arterial portography and CT hepatic arteriography for examination of liver tumors and then CT hepatic arteriography with prostaglandin E(1) injection via the superior mesenteric artery. All lesions pathologically confirmed to be hepatocellular carcinomas exhibited portal perfusion defects on CT during arterial portography. Changes in CT attenuation, size, and shape of liver tumors visualized on CT hepatic arteriography after intraarterial injection of prostaglandin E(1) were studied. In addition, changes in CT attenuation of the liver parenchyma surrounding the tumor were measured.

RESULTS

The CT attenuation increased significantly after injection of prostaglandin E(1) in 91% (39/43) of the lesions (mean increase from 176.4 to 206.6 H; p = 0.0006, paired t test). The size and shape of the enhanced area generally did not change. The CT attenuation of the liver parenchyma surrounding each liver tumor significantly decreased in 58% (25/43) of the hepatocellular carcinoma lesions (mean decrease from 94.8 to 92.0 H; p = 0.0166, paired t test) and lesion conspicuity increased in 91% (39/43) of the tumors.

CONCLUSION

Lesion conspicuity on CT hepatic arteriography between hepatocellular carcinoma and the surrounding liver parenchyma increased because of greater portal perfusion after the prostaglandin E(1) injection.

Unusual hemodynamics and pseudolesions of the noncirrhotic liver at CT

Recognition of pseudolesions of the liver at computed tomography (CT) is important because of their close resemblance to primary liver cancers or metastases. Two types of pseudolesion in the noncirrhotic liver include that due to transient extrinsic compression, typically caused by ribs or the diaphragm, and that due to a "third inflow" of blood from other than the usual hepatic arterial and portal venous sources: the cholecystic, parabiliary, or epigastric-paraumbilical venous system. Although the location of both types of pseudolesion are characteristic, their appearances at CT during arterial portography and CT during selective angiography vary from nonenhanced low-attenuation areas to well-enhanced high-attenuation areas, depending on the amount and timing of the inflow and presence or absence of focal metabolic alteration of the hepatocytes. Radiologists need to understand the underlying mechanism of these pseudolesions to better recognize the wide range of their appearances at CT.

Liver metastasis from gallbladder carcinoma: anatomic correlation with cholecystic venous drainage demonstrated by helical computed tomography during injection of contrast medium in the cholecystic artery

BACKGROUND

The current study evaluated whether the sites of liver metastasis from gallbladder carcinoma are correlated with areas of cholecystic venous drainage (CVD) utilizing helical computed tomography (CT) during the injection of contrast medium into the cholecystic artery (cholecystic artery CT).

METHODS

Cholecystic artery CT scans were performed in 26 patients with gallbladder carcinoma. Liver metastases were examined retrospectively in these patients on CT, and the sites of liver metastasis and CVD were compared closely. The patients were divided into concurrent (those who had metastasis at the time of cholecystic artery CT), early postoperative metastasis (those who developed metastasis within 6 months after surgery), and late postoperative metastasis (those who developed metastasis more than 6 months after surgery) groups. The frequency of metastasis related to CVD was compared between the three groups.

RESULTS

A total of 32 metastases were identified in 11 patients, 21 of which were related to CVD. Six patients were included in the concurrent metastasis group; 18 of 20 tumors were found to be related closely to CVD. There were two patients in the early postoperative metastasis group; all three of the tumors detected were found to be closely related to CVD. Three patients were subclassified as being in the late postoperative metastasis group; none of the nine tumors detected appeared to be in areas associated with CVD.

CONCLUSIONS

The sites of liver metastases were found to be well correlated with the areas with CVD, particularly in the concurrent and early postoperative metastasis groups. CVD may be a useful marker of potential areas of liver metastasis from gallbladder carcinoma, particularly in patients with early stage metastasis.

Value of intraarterial prostaglandin E(1) injection during CT hepatic arteriography

OBJECTIVE

The purpose of our investigation was to determine if injection of prostaglandin E(1) during CT hepatic arteriography could help physicians to distinguish tumors from nonportal venous flow-related pseudolesions in the region of the gallbladder fossa.

SUBJECTS AND METHODS

In 34 patients who underwent CT during arterial portography to detect liver tumors, CT hepatic arteriography was performed before and after prostaglandin E(1) injection via the superior mesenteric artery. Between each study, an interval of 10 minutes was set. On CT hepatic arteriogram obtained 15 to 20 sec after prostaglandin E(1) injection, we distinguished changes in the size and shape of pseudolesions in the liver around the gallbladder as well as those of 42 tumorous lesions. In addition, we measured the change in CT attenuation of pseudolesions.

RESULTS

The size of the enhanced area of pseudolesions visible on CT hepatic arteriography decreased in 69% (25/36) of the pseudolesions after intraarterial prostaglandin E(1) injection, with the mean diameter diminishing from 14.1 mm to 8.8 mm. Notably, in 11 pseudolesions, the enhanced area disappeared. In 86% (31/36), the CT attenuation decreased with the mean attenuation, diminishing from 211.3 H to 163.8 H. However, the size and shape of the enhanced area of tumorous lesions did not change.

CONCLUSION

The hemodynamic features of pseudolesions on angiographically assisted helical CT scans caused by cholecystic venous inflow are easily influenced by increased portal venous flow. Consequently, pseudolesions around the gallbladder usually can be distinguished from tumorous lesions by adding prostaglandin E(1) injection via the superior mesenteric artery during CT hepatic arteriography.

Intrahepatic portosystemic venous shunts: spectrum of CT findings in external and internal subtypes

PURPOSE

The purpose of this work was to survey the spectrum of CT findings in intrahepatic portosystemic venous shunts (IPSVSs).

METHOD

One thousand consecutive liver CT scans examined with an enhanced helical technique were retrospectively reviewed on workstation to find IPSVSs.

RESULTS

IPSVSs were noted in 37 patients and divided into two subtypes according to the location of the communicating systemic vein, either outside (external type, n = 34) or within (n = 4) the liver (one patient had both internal and external types). All the external-type shunts were noted in cases with portal hypertension (n = 34). Most shunts (n = 30) ran through segment 4 and/or 3 and came out near the falciform ligament, but five shunts were noted in segment 2 communicating either with the systemic vein (n = 3) or probably with an enlarged left gastric vein (n = 2). Solitary portohepatic venous shunts (internal type) were noted in three cases with (n = 2) or without (n = 1) aneurysmal dilatation and many portohepatic venous shunts in another patient.

CONCLUSION

IPSVSs of the external type were far common than those of the internal type, always associated with increased pressure of the portal system and in specific sites probably lacking the hepatic capsule.

Correlation of three-dimensional gradient echo dynamic MR imaging with CT during hepatic arteriography in patients with hypervascular hepatocellular carcinomas: preliminary clinical experience

The purpose of this study is to elucidate the usefulness of dynamic MR study of the whole liver using 3DFISP with double dose gadolinium (Gd) enhancement in detecting enhancing lesions in 20 patients. Twenty patients with hepatocellular carcinoma (HCC) underwent 3DFISP dynamic study with double dose Gd. The demonstration of enhancing hypervascular lesions regardless of etiology was evaluated on a segment-by-segment basis with receiver operating characteristic (ROC) analysis, using findings on CT during hepatic arteriography as a gold standard. Diagnostic accuracy of 3DFISP in the detection of HCC was also evaluated. As to the demonstration of enhancing lesions, the Az value of the ROC curve was 88%. The detection rate of HCC with 3DFISP was 98%. 57% of enhancing pseudolesions were not detected on 3DFISP. We concluded that Dynamic MR study of the whole liver using 3DFISP with double dose Gd enhancement is a useful method to demonstrate hypervascular HCC.

Focal fatty infiltration in the posterior aspect of hepatic segment IV: relationship to pancreaticoduodenal venous drainage

OBJECTIVE

We aimed to investigate the relationship between fatty infiltration in the posterior aspect of hepatic segment IV and pancreaticoduodenal venous drainage.

METHODS

Pancreaticoduodenal arteriography was performed in 21 patients who had nontumorous portal perfusion defects in the posterior aspect of hepatic segment IV, as demonstrated on CT during arterial portography (CTAP).

RESULTS

In 10 patients, pancreaticoduodenal arteriography showed an aberrant nonportal vessel with flow toward the hepatic hilum in the venous phase. Four of the 10 patients with nonportal vessels from the pancreaticoduodenal arterial system had fatty infiltration in segment IV. In three of these four patients, the fatty infiltration was focal and localized to that area. On the other hand, none of the 11 patients without nonportal vessels from the pancreaticoduodenal arterial system had fatty infiltration in the regions corresponding to the nontumorous portal perfusion defects on CTAP. Moreover, three patients with diffuse fatty liver had a focal nonfatty area in segment IV.

CONCLUSIONS

Focal fatty infiltration in the posterior aspect of hepatic segment IV seems to be related to pancreaticoduodenal venous drainage.