Enhancement In Venous Phase Research Articles

Can MDCT or EUS features predict the histopathological grading scheme of pancreatic neuroendocrine neoplasms?

To identify whether the features of preoperative MDCT or EUS could predict the histopathological grading scheme of pancreatic neuroendocrine neoplasms (pNENs). A total of 25 patients with pNENs were enrolled in the present study. The qualitative and quantitative variables were reviewed. The qualitative variables included location, contour, border, necrosis, intratumoral vessel, homogeneity, calcification, peripancreatic fat/vessel infiltration, pancreatic duct dilatation, mass within pancreas, lymphadenopathy and hepatic metastasis on MDCT and border, echogenicity, cystic/solid and blood flow on EUS. The quantitative variables included long diameter (LD), short diameter (SD), unenhanced mass attenuation (UMA), unenhanced pancreatic attenuation (UPA), arterial phase mass attenuation (APMA), arterial phase pancreatic attenuation (APPA), portal venous phase mass attenuation (PVPMA), portal venous phase pancreatic attenuation (PVPPA), arterial phase enhancement degree (APED) and portal venous phase enhancement degree (PVPED). In addition, sex and age were also evaluated. Histopathological classifications met the criterion of 2010 edition WHO Histopathological Classifications. Kruskal-Wallis test and Boruta algorithm were conducted. Lymphadenopathy and peripancreatic fat or vascular invasion foretold higher histopathological grading level while well-defined border on EUS image lower grading level. Lymphadenopathy, border on EUS image and peripancreatic fat or vascular invasion can predict the histopathological grading scheme of pNENs.

The Value of Dual-Phase Enhancement CT as a Predictor of the Preoperative Preparation of Adrenal Pheochromocytoma

The purpose of this study was to evaluate the function of adrenal pheochromocytoma with the value of dual-phase enhancement computed tomography (CT) and to guide the preoperative preparation of adrenal pheochromocytoma. From June 2009 to December 2015, the patients with a diagnosis of pheochromocytoma were divided into 2 groups according to the length of preparation time (group 1, ≤2 weeks; group 2, >2 weeks). Two experienced radiologists measured adrenal lesion attenuation from dual-phase, contrast-enhanced CT examinations. Student t-test analysis was performed to compare arterial and venous phase enhancement levels and the maximum increased enhancement CT value. There were 31 cases of pheochromocytoma that were accepted into the study: 13 cases in group 1 and 18 cases in group 2. At contrast-enhanced CT, the mean arterial enhancement and venous enhancement of pheochromocytoma were 74 ± 20 Hounsfield units (HU; range, 50–107 HU) and 72 ± 18 HU (range, 44–109 HU), respectively, in group 1, which were significantly less than those in group 2, with a mean of 101 ± 26 HU (range, 64–138 HU) and 100 ± 22 HU (range, 61–131 HU; P < 0.05). The average maximum increased attenuation at enhancement CT in group 1 was 41 ± 12 HU (range, 24–62 HU), significantly less than that in group 2, with a mean of 62 ± 22 HU (range, 26-102 HU; P < 0.05). The preparation time was related to the absolute enhancement level, especially with the maximum increased attenuation of pheochromocytoma at enhanced CT. More preparation time before surgery was needed if the maximum enhancement level during arterial phase and venous phase was greater than 109 HU and the maximum increased attenuation was greater than 62 HU.

CT characteristics of the sero-hepatic type of hepatic tuberculosis

Objective To study the CT features of the sero-hepatic type of hepatic tuberculosis. Methods This is a retrospective, multi-center and cross-sectional study. 17 patients with the sero-hepatic type of hepatic tuberculosis from the Yueqing People’s Hospital (n=5), Second Affiliated Hospital of Wenzhou Medical College (n=5), and Wenzhou People’s Hospital (n=7) were studied. All these patients were fasted for 8 h prior to CT scanning. They underwent enhanced after conventional CT breathless scanning with no abdominal pressure. Results The CT scans displayed 41 lesions in these 17 patients with the sero-hepatic type of hepatic tuberculosis, including a solitary lesion in 13 patients and multiple lesions in 4 patients. The diameter of the lesions varied from 0.8 to 4.7 cm, with a mean ± S. D. of 2.38±4.82 cm. The CT features showed a localized spindle-shaped focal lesion just underneath the liver capsule with resultant concave compression of the adjacent liver tissue (n=22), spotted calcifications in the center of the focal nodules (n=1); and aggregation of multiple low density nodular foci (n=19). Additional CT features included focal nodules surrounded by a small amount of liquid (n=15), compression of adjacent liver tissue (n=22), a small amount of ascites (n=8), and retroperitoneal lymph nodes enlargement (n=2). These nodules showed moderate (n=5) and slight enhancement in the arterial phase (n=36); moderate (n=32) and mild enhancement in the portal venous phase (n=9); and moderate (n=32) and mild enhancement in the parenchymal phase (n=9), respectively. The nodules showed ring-shaped (n=26), honeycomb or multiple ring-shaped enhancement (n=15). The enhanced ring-shaped wall thickness varied from 0.2 to 0.9 cm, with a thin wall (n=30) and a thick wall (n=11). The center of the focal nodule was a low density sac-shaped area, with no obvious contrast enhancement. The CT value was 21 to 39 hu. The infiltrative liver tissues which surrounded the focal nodules were shown as lamellar areas of obvious arterial enhancement, with equidensity in the portal vein phase and equilibrium phase. Conclusions CT showed characteristic features of the sero-hepatic type of hepatic tuberculosis. Clinical and laboratory findings could provide important supplementary information to make the diagnosis. Key words: Hepatic tuberculosis, sero-hepatic type; Tomography, X-ray computed

3:18 PMAbstract No. 338 - Pre and post-procedural evaluation of imaging biomarkers after radioembolization for hepatocellular carcinoma as an indicator of progression

The purpose of this study is to evaluate possible imaging biomarkers on contrast-enhanced CT and MRI exams that predict local progression per modified Response Evaluation Criteria in solid tumors (mRECIST) criteria post radioembolization of hepatocellular carcinoma (HCC). Among patients who underwent radioembolization for HCC between May 1, 2005 and May 1, 2015 at a single institution, 34 patients had adequate pre and at least 2 post-procedural exams. Local response to treatment was classified as progressive (PD) or stable disease (SD) using mRECIST. Imaging markers, including portal venous phase enhancement (PVE), lobulated enhancement (LE), presence of arterioportal shunting (APS), and portal vein thrombosis (PVT) were assessed in each imaging examination. Wilcoxen Rank-Sum (WRS) and log-rank analyses were performed to establish statistically significant differences in local progression free survival (LPFS). The mean imaging follow-up time was 12.64 months. Local progression was seen in 25 patients (73.5%) following radioembolization. Average time to progression was 2.9 months. PVT, APS, and PVE seen on pre or post-procedural imaging were not significant predictors of LPFS. LE on immediate post-procedural imaging was a significant predictor of progression by WRS (p=0.039) and log-rank analysis (p=0.037), however LE on pre-procedural imaging was not a significant predictor. 9 patients with and 0 patients without progression showed LE on pre or post-procedural imaging, respectively. PVT, APS, and portal venous enhancement were not statistically significant predictors of local progression, whereas immediate post-procedural LE demonstrated a statistically significant decrease in LPFS in patients with hepatocellular carcinoma treated with radioembolization.

Differentiation of mass-forming intrahepatic cholangiocarcinoma from poorly differentiated hepatocellular carcinoma: based on the multivariate analysis of contrast-enhanced computed tomography findings.

We aim to gain further insight into identifying differential radiological features of mass-forming intrahepatic cholangiocarcinoma (mICC) from poorly differentiated hepatocellular carcinoma (pHCC) on contrast-enhanced computed tomography (CT). 107 patients with pathologically confirmed mICC (n=48) and pHCC (n=59) who had undergone preoperative contrast-enhanced CT were enrolled. Qualitative analysis of CT images were evaluated for tumor demarcation, shape, presence of satellite nodules, capsular retraction, biliary involvement, intratumoral arteries, tortuous tumoral vessels, vascular invasion, portal vein tumor thrombus, arterial enhancement pattern, portal venous phase enhancement, and washout pattern. Quantitative analysis was performed for mean attenuation of tumor and tumor-to-liver contrast during each phase. The degree of arterial enhancement was graded based on quantitative measurements. A lobulated shape, indistinct margin, peripheral rim enhancement in the arterial phase, and the presence of bile duct dilatation were CT features favoring mICC, whereas a round shape, partially indistinct margin, heterogeneous enhancement in the arterial phase, washout pattern and the presence of tortuous tumoral vessels were CT features favoring pHCC in the univariate analysis (P<0.05). Tumor-to-liver contrast of pHCC was greater than that of mICC during the arterial phase (P=0.015). In the multivariate analysis, bile duct dilatation, tortuous tumoral vessels, and a washout pattern were independent CT features for distinguishing between the two types. (P=0.003, P=0.003, P=0.044, respectively). The absence of a washout pattern and tortuous tumoral vessels and presence of bile duct dilatation are more indicative of mICC than of pHCC on contrast-enhanced CT.

Interobserver agreement of semi-automated and manual measurements of functional MRI metrics of treatment response in hepatocellular carcinoma

PurposeTo assess the interobserver agreement in 50 patients with hepatocellular carcinoma (HCC) before and 1 month after intra-arterial therapy (IAT) using two semi-automated methods and a manual approach for the following functional, volumetric and morphologic parameters: (1) apparent diffusion coefficient (ADC), (2) arterial phase enhancement (AE), (3) portal venous phase enhancement (VE), (4) tumor volume, and assessment according to (5) the Response Evaluation Criteria in Solid Tumors (RECIST), and (6) the European Association for the Study of the Liver (EASL). Materials and methodsThis HIPAA-compliant retrospective study had institutional review board approval. The requirement for patient informed consent was waived. Tumor ADC, AE, VE, volume, RECIST, and EASL in 50 index lesions was measured by three observers. Interobserver reproducibility was evaluated using intraclass correlation coefficients (ICC). P<0.05 was considered to indicate a significant difference. ResultsSemi-automated volumetric measurements of functional parameters (ADC, AE, and VE) before and after IAT as well as change in tumor ADC, AE, or VE had better interobserver agreement (ICC=0.830–0.974) compared with manual ROI-based axial measurements (ICC=0.157–0.799). Semi-automated measurements of tumor volume and size in the axial plane before and after IAT had better interobserver agreement (ICC=0.854–0.996) compared with manual size measurements (ICC=0.543–0.596), and interobserver agreement for change in tumor RECIST size was also higher using semi-automated measurements (ICC=0.655) compared with manual measurements (ICC=0.169). EASL measurements of tumor enhancement in the axial plane before and after IAT ((ICC=0.758–0.809), and changes in EASL after IAT (ICC=0.653) had good interobserver agreement. ConclusionSemi-automated measurements of functional changes assessed by ADC and VE based on whole-lesion segmentation demonstrated better reproducibility than ROI-based axial measurements, or RECIST or EASL measurements.

MDCT of Adrenal Masses: Can Dual-Phase Enhancement Patterns Be Used to Differentiate Adenoma and Pheochromocytoma?

The purpose of this study was to compare enhancement of adrenal adenomas and pheochromocytomas during dual-phase (arterial and venous phases) CT performed with currently used MDCT protocols with the goal of defining enhancement patterns predictive of pathologic findings. Pathologically proven pheochromocytomas were retrospectively compared with adrenal adenomas. Inclusion criteria for adenomas, collected by searching the radiology database, were confirmatory adrenal CT (unenhanced with or without washout) and absence of clinical indicators of pheochromocytoma. A fellowship-trained attending radiologist blinded to the pathologic diagnosis reviewed existing images from dual-phase IV contrast-enhanced CT examinations to measure enhancement of adrenal lesions and characterize the appearance (homogeneous versus heterogeneous). Student t test analysis was performed to compare arterial and venous phase enhancement levels. The findings in 39 patients with 41 adenomas were compared with those in 10 patients with 12 pheochromocytomas. Mean arterial and venous enhancement of adenomas at 37 HU (-6 to 85 HU) and 60 HU (16-133 HU) was significantly lower than that of pheochromocytomas at 104 HU (42-190 HU) and 119 HU (61-195 HU) (p < 0.001). No adenoma was more than 85-HU enhancing in the arterial phase, and 58% of pheochromocytomas were more than 110-HU enhancing. Most adenomas (85%) were more enhancing in the venous phase. No adenoma was more enhancing in the arterial phase, but 25% (3/12) of pheochromocytomas were. Most (58%) pheochromocytomas were heterogeneous in appearance, compared with 22% of adenomas. For indeterminate adrenal masses identified at dual-phase IV contrast-enhanced CT, higher enhancement during the arterial phase, arterial phase enhancement levels greater than 110 HU, and lesion heterogeneity should prompt consideration of pheochromocytoma.

Establishment and evaluation of implanted inferior vena cava tumor thrombus model in New Zealand white rabbits

Objective To establish an animal model of implanted inferior vena cava tumor thrombus (IVCTT) and examine its growth with MDCT and 3D-MPR. Methods Tumor cell line VX2 was inoculated subcutaneously into rabbit to develop the primary tumor, which was then cut into small strips. Purse-string suture was performed on the anterior wall of IVC after the laparotomy in eighteen New Zealand white rabbits.The tumor strip was injected into IVC through the purse and suspensory fixed on the inner wall of IVC. The general conditions,body weight,and the survival time were monitored after operations.MDCT examinations were performed with plain scan,arterial phase,portal phase and venous phase enhancement every week for all animals and 3D-MPR were acquired.The volumes of IVCTT were calculated.IVC,IVCTT and metastasis were examined with gross and histological pathology. Results The IVCTT was confirmed by MDCT and 3D-MPR images.Collateral varicose veins caused by IVC obstruction and metastasis were also shown in images.IVCTT and metastasis were confirmed by pathological method. The success rate of IVCTT was 100 ％. The mean survival time of operated animals was (49.5±4.4) days. Conclusions Injecting and suspensory fixing VX2 tumor strip into IVC is a reliable method to establish the IVCTT animal model. MDCT and 3D-MPR are valuable methods to monitor the growth and metastasis of IVCTT in animal models. The model of implanted IVCTT of rabbits provides a useful tool for the research of treatment of IVCTT. Key words: Cell line,VX2; Models,animal; Vena cava,inferior; Neoplastic cells,circulating; Tomography,spiral computed

Behavior of Hepatocellular Adenoma on Real-time Low-Mechanical Index Contrast-Enhanced Ultrasonography With a Second-Generation Contrast Agent

The purpose of this study was to describe the behavior of histologically proven hepatocellular adenoma (HCA) on low-mechanical index (MI) contrast-enhanced ultrasonography (CEUS). A review of the databases from 4 academic hospitals revealed 18 patients (15 female and 3 male; mean age, 40 years; range, 25-71 years) with 25 histologically proven HCA lesions who were studied with CEUS at a low MI (0.04-0.1). Twenty-four of 25 lesions (96%; 95% confidence interval [CI], 80.5%-99.3%) showed high-intensity enhancement, scored as 3 on a scale of 0 to 3, whereas only 1 lesion (4%; 95% CI, 0.7%-19.5%) was scored as 2. The time of peak enhancement ranged between 10 and 19 seconds (average, 13 seconds). All but 1 of the 25 lesions (96%; 95% CI, 80.5%-99.3%) showed early homogeneous and centripetal enhancement during the hepatic arterial phase. No portal venous phase enhancement was observed in any lesion because all showed rapid wash-out (100%; 95% CI, 86.7%-100%). Twenty lesions (80%; 95% CI, 60.9%-91.1%) were found to be isoechoic to slightly hypoechoic during the portal phase, and 19 (76%; 95% CI, 56.6%-88.5%) were isoechoic to mildly hypoechoic, whereas 7 (24%; 95% CI, 11.5%-43.4%) were hypoechoic during the late phase. Contrast-enhanced ultrasonography is an effective technique for identifying the microvascular and macrovascular characteristics of HCA. Typically, HCA shows early (10-19 seconds) and centripetal enhancement during the arterial phase and isoechogenicity or mild hypoechogenicity during the portal phase, remaining slightly hypoechoic or isoechoic during the late phase in most cases.

Enhancement Patterns of Hepatocellular Carcinoma at Contrast-enhanced US: Comparison with Histologic Differentiation

To retrospectively compare the arterial and portal venous phase enhancement patterns of hepatocellular carcinoma (HCC) at contrast material-enhanced ultrasonography (US) with the degree of HCC histologic differentiation. This study was approved by the research ethics board, and informed consent was obtained. The study population included 112 consecutive patients (91 men, 21 women; aged 25-86 years) with 112 histologically proved HCCs: 23 well differentiated, 77 moderately differentiated, and 12 poorly differentiated. All underwent continuous real-time low-mechanical-index contrast-enhanced US from wash-in of contrast material to 300 seconds by using a blood-pool microbubble agent. Initial image interpretation included arterial enhancement, dysmorphic intratumor arteries, and presence and time of negative enhancement (washout). Enhancement patterns were compared with histologic differentiation by using the Fisher exact test. In the arterial phase, 97 of 112 (87%) HCCs showed hypervascularity, with a significantly higher proportion in moderately differentiated HCCs (74 of 77, 96%) when compared with well- (14 of 23, 61%; P<.001) and poorly differentiated HCC (nine of 12, 75%; P<.004). Eight of 112 (7%) were isovascular and seven (6%) were hypovascular. Dysmorphic arteries were seen in 81 (72%) HCCs. Of 97 hypervascular tumors, only 42 (43%) showed typical washout by 90 seconds. Late washout appeared in 25 (26%) HCCs in the 91-180 seconds phase and in 21 (22%) in the 181-300 seconds phase. The remaining nine showed no washout up to 300 seconds and seven (78%) were well-differentiated HCCs. Moderately differentiated HCC generally shows classic enhancement features, while well- and poorly differentiated tumors account for most atypical variations. Extended observation in the portal phase is important as late washout occurs with slightly more frequency than washout in the conventionally defined portal venous phase.

Hepatic malignant fibrous histiocytoma of imaging characteristics

目的 提高对肝脏恶性纤维组织细胞瘤影像学表现的认识.方法回顾性分析4例经手术或活检病理证实的肝脏恶性纤维组织细胞瘤的影像学特点,其中包括CT 4例, MRI 2例,肝动脉DSA 1例.结果 4例肿瘤均位于肝右叶,肿瘤呈浸润性生长,与周围肝实质分界不清,3例侵犯肝包膜.4例CT平扫均表现为不规则形低密度灶,CT值28～36 HU,其中2例可见片状稍高密度出血灶;增强扫描动脉期肿瘤实质呈轻度强化,CT值52～70 HU,静脉期呈中度强化,CT值75 ～98 HU,病灶内部中央坏死显著.2例表现为T1WI低信号,与肌肉信号相当,其中1例病灶内见片状等高信号影,T2WI为较高信号.1例DSA表现为肝动脉分支走行呈抱球状,实质期可见不规则肿瘤染色.结论肝脏恶性纤维组织细胞瘤的影像学表现主要为肿瘤向外浸润明显,边界不清,肿瘤内部坏死显著,实质部分所占比例很小,瘤内出血常见。

Cholangiocarcinoma

Cholangiocarcinoma

CT imaging of collecting duct carcinoma of the kidney

目的 提高对肾脏集合管癌CT表现的认识.方法报告3例经病理证实的肾脏集合管癌的螺旋CT所见,并作文献复习.结果男2例,女1例,肿瘤位于右肾者2例,左肾1例.位于右肾的1例,肿瘤累及肾皮质和髓质,并突出于肾轮廓之外,大小约8.0 cm×8.0 cm,平扫CT值约37～45 HU,其内见高密度的斑点状钙化灶.增强动脉期(皮质期)及静脉期(髓质期)扫描示病变呈不均匀性强化,无包膜,CT值约52～107 HU,CT诊断为右肾癌,但不排除肾结核.另外2例肿瘤同时累及肾皮质、髓质及肾盂,其中位于左肾的1例,肿瘤大小约7.0 cm×7.5 cm,平扫病变区CT值约22 HU,增强动脉期(皮质期)扫描示肾皮、髓分界不清,病变区CT值约70 HU,静脉期(髓质期)示肾静脉内癌栓形成,排泄期(肾盂期)扫描示左肾盂、肾盏未见显影,CT诊断为左肾癌(集合管癌可能性大).另外1例位于右肾,肿瘤大小约8.0 cm×14.0 cm,平扫CT值约32 HU,增强动脉期(皮质期)及静脉期(髓质期)扫描示肿瘤与正常的肾组织无明显分界,CT值约45～72 HU,排泄期(肾盂期)扫描示左肾盂、肾盏未见显影,CT诊断为右肾癌,但不排除肾结核.3例中2例可见肾周脂肪囊及肾筋膜受侵犯,2例有局部淋巴结转移,1例有肋骨转移.结论 CT对肾脏集合管癌的定性诊断有一定的价值,但确诊还应依赖于病理。

Alterations in hepatic perfusion resulting from splanchnic venous luminal compromise caused by pancreatic carcinoma.

We determined whether alterations in hepatic enhancement exist on dual phase helical CT of the liver in patients with splanchnic venous luminal compromise resulting from pancreatic adenocarcinoma. We examined the extent of hepatic enhancement on dual phase helical CT in 22 patients with pancreatic adenocarcinoma. Eleven patients had splanchnic venous luminal narrowing (flattening along at least 120 degrees of the circumference) of the superior mesenteric vein with (n = 3) or without (n = 8) portal vein involvement caused by tumor. In the remaining patients, splanchnic vasculature appeared normal. An additional 16 patients without pancreatic or hepatic abnormality who underwent dual phase helical CT served as control subjects. We compared the extent of arterial phase and portal venous phase enhancement among the three groups. The group of patients with splanchnic venous luminal compromise had significantly higher hepatic enhancement during the arterial phase (p < 0.01) and lower enhancement during the portal venous phase (p < 0.05) compared with the other two groups of patients. No significant difference in hepatic enhancement during either phase was noted between the control subjects and the patients with normal vasculature. Because hepatic enhancement correlates with perfusion, splanchnic venous luminal compromise resulting from pancreatic adenocarcinoma likely causes decreased portal venous flow and compensatory increased hepatic arterial flow. This finding supports other evidence of a homeostatic mechanism that maintains hepatic perfusion.