Enhancement In Portal Phase Research Articles

Laparoscopic liver resection or enucleation for giant hepatic hemangioma: how to choose?

Laparoscopic treatment has been increasingly adopted for giant hepatic hemangioma (HH), but the role of liver resection or enucleation remains uncertain. The aim of this study is to compare the laparoscopic resection (LR) with laparoscopic enucleation (LE) for HH, and to provide evidence on how to choose the most suitable approach for HH. A retrospective analysis of HH patients underwent laparoscopic treatment between March 2015 and August 2022 was performed. Perioperative outcomes were compared based on the surgical approaches, and risk factors for increased blood loss was calculated by logistic regression analysis. A total of 127 patients in LR group and 287 patients in LE group were enrolled in this study. The median blood loss (300 vs. 200mL, P < 0.001) was higher in LE group than that in LR group. Independent risk factors for blood loss higher than 400mL were tumor size ≥ 10cm, tumor adjacent to major vessels, tumor occupying right liver or caudate lobe, and the portal phase enhancement ratio (PER) ≥ 38.9%, respectively. Subgroup analysis showed that LR was associated with less blood loss (155 vs. 400mL, P < 0.001) than LE procedure in patients with high PER value. Both LR and LE approaches exhibited similar perioperative outcomes in patients with low PER value. Laparoscopic treatment for HH could be feasibly and safely performed by both LE and LR. For patients with PER higher than 38.9%, the LR approach is recommended.

Prediction of bowel necrosis by reduced bowel wall enhancement in closed-loop small bowel obstruction: Quantitative methods

PurposeTo assess diagnostic performance and reproducibility of reduced bowel wall enhancement evaluated by quantitative methods using CT to identify bowel necrosis among closed-loop small bowel obstruction (CL-SBO) patients. MethodsThis retrospective single-center study included patients who diagnosed with CL-SBO caused by adhesion or internal hernia during January 2016 and May 2022. Patients were divided into necrotic group (n = 41) and non-necrotic group (n = 67) according to surgical exploration and postoperative pathology. Two doctors independently measured the attenuation of bowel wall and consensus was reached through panel discussion with a third gastrointestinal radiologist. Reduced bowel wall enhancement was assessed by four quantitative methods. Univariate analyses were used to evaluate the association between each method and bowel necrosis, and kappa/intraclass correlation coefficient values were used to assess interobserver agreement. Diagnostic performance parameters were calculated for each method. ResultsReduced bowel wall enhancement in arterial phase (OR 8.98, P < 0.0001), reduced bowel wall enhancement in portal phase (OR 16.84, P < 0.001), adjusted reduced bowel wall enhancement in arterial phase (OR 29.48, P < 0.001), adjusted reduced bowel wall enhancement in portal phase (OR 145.69, P < 0.001) were significantly associated with bowel necrosis. Adjusted reduced bowel wall enhancement in portal phase had the best diagnostic performance (AUC: 0.92; Youden index: 0.84; specificity: 94.03 %) and interobserver agreement (kappa value of 0.59–0.73) to predict bowel necrosis. ConclusionWhen assessing reduced bowel enhancement to predict bowel necrosis among CL-SBO patients, using unenhanced CT images and proximal dilated loop as standard references in portal phase is the most accurate quantitative method among those tested.

Recognizing the Role of the Reticuloendothelial System in the Late Phase of US Contrast Agents.

Recognizing the Role of the Reticuloendothelial System in the Late Phase of US Contrast Agents.

CT and MRI findings of primary hepatic neuroendocrine neoplasm

Objective: To study imaging features of primary hepatic neuroendocrine neoplasm (PHNEN) with CT and MRI. Methods: CT/MRI findings of ten patients with pathologically confirmed PHNEN were retrospectively analyzed. The result was compared with pathologic features classified by the 2010 WHO classification of gastro-entero-pancreatic neuroendocrine tumor which was also compared with the conventional method. Results: Six cases of neuroendocrine tumor (NET), all of which were classified as grade 2 (G2), consisted of 5 cases of carcinoid and 1 case of atypical carcinoid. Four cases of neuroendocrine carcinoma (NEC) classified as grade 3 (G3) were composed of 1 case of atypical carcinoid and 3 cases of small cell carcinoma. On the basis of conventional classification method, CT/MRI features were as follows: (1) Carcinoid: For 5 carcinoid cases, two with solitary mass, two with dominant masses and satellite nodules, and one with diffused nodules. Four cases were cystic-solid and one was solid. Four showed low density on plain CT and moderate to obvious enhancement in arterial phase. Three showed consistent enhancement in portal and delayed phase while one showed rapid washout in portal phase. Four showed low density in delayed phase. One case with cystic degeneration showed hypo-intensity on T1W, hyper-intensity on T2W and halo like hyper-intensity on DWI. In dynamic MRI, the solid part of tumor showed obvious enhancement in arterial phase, consistent enhancement in portal phase with slight washout and homogeneous or slight hypo-geneous signal density in delayed phase. (2) Atypical carcinoid: Two cases presented with cystic-solid mass. They were all dominant masses with satellite nodules. They showed low density on plain CT and mild to moderate enhancement in arterial phase. One case showed rapid washout in portal and delayed phase with embolus in portal vein. The other case showed consistent enhancement in portal phase and hypo-density in delayed phase without enhancement of satellite nodules. (3) Small cell neuroendocrine carcinoma: Three cases of small cell carcinoma were composed of one cystic-solid tumor, one solid tumor and one dominant mass with satellite nodules. Two cases showed low density in CT plain scan while one with cystic degeneration presented hypo-intensity on T1W, hype-rintensity on T2W and halo like hyper-intensity on DWI. Dynamic CT and MRI showed mild to moderate enhancement in arterial phase, consistent enhancement in portal phase and low density or hypo-intensity in delayed phase. Conclusion: PHNEN has specific features on CT and MRI which are valuable in diagnosis and differential diagnosis.

Quantitative Measurements of Enhancement on Preprocedure Triphasic CT Can Predict Response of Colorectal Liver Metastases to Radioembolization.

Colorectal liver metastases (CLM) have a variable response to radioembolization. This may be due at least partly to differences in tumor arterial perfusion. The present study examines whether quantitative measurements of enhancement on preprocedure triphasic CT can be used to predict the response of CLM to radioembolization. We retrospectively reviewed patients with CLM treated with radioembolization who underwent pretreatment PET/CT and triphasic CT examinations and posttreatment PET/CT examinations. A total of 31 consecutive patients with 60 target tumors were included in the present study. For each tumor, we calculated the hepatic artery coefficient (HAC), portal vein coefficient (PVC), and arterial enhancement fraction (AEF) based on enhancement measurements on pretreatment triphasic CT. HAC and PVC are estimates of the hepatic artery and portal vein blood supply. AEF, which is the arterial phase enhancement divided by the portal phase enhancement, provides an estimate of the hepatic artery blood supply as a fraction of the total blood supply. For each tumor, the metabolic response to radioembolization was based on findings from the initial follow-up PET/CT scan obtained at 4-8 weeks after treatment. A total of 55% of CLM had a complete or partial metabolic response. Arterial phase enhancement, the HAC, and the PVC did not predict which tumors responded to radioembolization. However, the AEF was statistically significantly greater in tumors with a complete or partial metabolic response than in tumors with no metabolic response (i.e., those with stable disease or disease progression) (p = 0.038). An AEF of less than 0.4 was associated with a 40% response rate, whereas an AEF greater than 0.75 was associated with a 78% response rate. Response to radioembolization can be predicted using the AEF calculated from the preprocedure triphasic CT.

Findings in multi-detector row CT with portal phase enhancement in patients with mesenteric venous thrombosis

There exists no systematic evaluation on the findings in multi-detector row computed tomography (MDCT) with portal phase enhancement in patients with mesenteric venous thrombosis (MVT). Patients with MVT between 2004 and 2006 were identified at Malmö University Hospital, Sweden. Thirty patients had MVT. Median age was 58 years (interquartile range, 46-72), and 57% (17) were men. MDCT with portal phase enhancement showed MVT in 19 out of 20 investigated patients at first evaluation, even though there was clinical suspicion in only one, and conservative management was possible in 19 (95%). Central and peripheral MVT was seen in 20 (100%) and six (30%) cases, respectively. Extra-hepatic and intra-hepatic portal and splenic vein thrombosis was seen in 17 (85%), nine (45%) and 15 (75%) cases, respectively. Venous collaterals were visible in 12 (60%) cases. The most frequent extra-vascular pathologies were mesenteric oedema (50%), ascites (40%), small bowel wall oedema (25%) and local small bowel wall dilatation (20%). The vascular findings in MVT are more pronounced than the intestinal findings in MDCT with portal phase enhancement, and evaluation of the mesenteric vessels should be included in routine MDCT scans for unclear acute abdomen.

Enhancement and safety of iomeprol-400 and iodixanol-320 in patients undergoing abdominal multidetector CT

The purpose of this study was to compare iomeprol-400 and iodixanol-320 for contrast enhancement and safety in patients undergoing liver multidetector CT (MDCT). 183 patients undergoing MDCT received equi-iodine (40 gI) iomeprol-400 (n = 91) or iodixanol-320 (n = 92) IV at 4 ml s(-1). Two off-site, independent, blinded readers determined the contrast density (in Hounsfield units (HUs)) in the abdominal aorta, inferior vena cava, portal vein and liver parenchyma during the arterial and portal phases. The mean contrast densities achieved were compared and 95% confidence intervals (CIs) estimated. Heart rate was measured at baseline and at post-dose peak, and a full safety assessment was performed. Study group demographics were comparable. Iomeprol-400 produced significantly greater enhancement of the aorta during the arterial phase (Reader 1: 337.3 HU vs 294.9 HU, 95% CI of difference (19.4, 65.5), p = 0.0004; Reader 2: 325.7 HU vs 295.3 HU, 95% CI of difference (6.6, 54.3), p = 0.01) and greater enhancement of the liver parenchyma during the portal venous phase (Reader 1: 115.1 H vs 108.6 HU, 95% CI of difference (0.27, 12.7), p = 0.04; Reader 2: 115.2 H vs 109.3 HU, 95% CI of difference (-0.1, 11.8), p = 0.05). Similar enhancement of the inferior vena cava and portal vein was noted. Comparably negligible increases in the mean heart rate were observed. Adverse events occurred in 1/91 (1.1%) subjects after iomeprol-400 and 4/92 (4.3%) subjects after iodixanol-320. In conclusion, iomeprol-400 produces greater arterial and portal phase enhancement and has a similarly negligible impact on heart rate and safety.

Focal Nodular Hyperplasia and Hepatic Adenoma: Differentiation with Low-Mechanical-Index Contrast-Enhanced Sonography

The purpose of our study was to determine the differentiating features of focal nodular hyperplasia (FNH) and hepatic adenoma on contrast-enhanced sonography. Sixty-two patients who underwent contrast-enhanced sonography and were confirmed to have FNH (n = 43) or hepatic adenoma (n = 19) were assessed retrospectively for arterial phase enhancement, filling direction, stellate arteries, and portal phase enhancement. An algorithm was applied to these interpreted features to determine the contrast-enhanced sonography diagnosis. All lesions were hypervascular in the arterial phase. Centrifugal filling was more common in FNH (39 and 32 of 43, 91% and 74% [reader 1 and reader 2]) than in adenoma (3 and 3 of 19, 16%). Centripetal or mixed filling was more common in adenoma (16 and 16 of 19, 84%) than in FNH (4 and 11 of 43, 9% and 26%) (p < 0.001, kappa = 0.61). Stellate arteries characterized FNH (29 and 26 of 43, 67% and 60%) but not adenoma (3 and 2 of 19, 16% and 11%) (p < 0.001, kappa = 0.36). Sustained portal phase enhancement was more common in FNH (37 and 39 of 43, 86% and 91%) than in adenoma (9 and 12 of 19, 47% and 63%) (p < 0.02, kappa = 0.79). The sensitivity, specificity, positive predictive value, and negative predictive value of sonography for diagnosing FNH were 95% and 86%, 74% and 79%, 89% and 90%, and 88% and 71%, (reader 1 and reader 2, respectively). FNH is predicted on the basis of arterial phase centrifugal filling and stellate vascularity on contrast-enhanced sonography. Adenoma is less reliably predicted on the basis of centripetal or mixed filling without stellate vascularity. Sustained portal phase enhancement is more common in FNH than in adenoma but contributes less to the differentiation of these lesions.

An Algorithm for the Diagnosis of Focal Liver Masses Using Microbubble Contrast-Enhanced Pulse-Inversion Sonography

The objective of this study was to develop an algorithm for liver mass diagnosis using microbubble contrast-enhanced pulse-inversion sonography. Ninety-six lesions in 92 patients were evaluated with DMP 115 (Definity)-enhanced pulse-inversion sonography, comprising 44 malignancies (29 hepatocellular carcinomas, 12 metastases, two peripheral cholangiocarcinomas, and one hepatic lymphoma) and 52 benign lesions (26 hemangiomas, 20 focal nodular hyperplasias, and six others). All had continuous low-mechanical-index imaging through the arterial and portal venous phase. A three-person blind review evaluated single images at baseline, early and peak arterial phases, and through the extended portal phases with a movie showing arterial phase wash-in. Reviewers assessed lesional vascularity and enhancement blindly but did not make a diagnosis. Combinations of answers were compared with independently determined final diagnoses to develop an algorithm for liver mass diagnosis. Portal phase enhancement comprises the first step of the algorithm, with positive or sustained enhancement identifying 48 (92%) of 52 benign lesions and negative enhancement or washout present in 41 (93%) of 44 malignancies. Sustained portal phase enhancement with arterial phase peripheral nodularity and centripetal progression predicted 24 (92%) of 26 of the hemangiomas; diffuse arterial phase enhancement greater than the liver identified 19 (95%) of 20 of the focal nodular hyperplasias. With negative portal phase enhancement, arterial phase information was less effective at differentiating hepatocellular carcinoma (25 [86%] of 29 cases) from another hepatic malignancy (11 [73%] of 15 cases). A simple diagnostic algorithm for interpretation of microbubble-enhanced sonography provides sensitive and accurate diagnosis of commonly encountered liver masses.