Portovenous Phase Research Articles

Delayed bolus-tracking trigger at CT correlates with cardiac dysfunction and suboptimal portovenous contrast phase.

To assess whether delayed trigger during bolus-tracking for CT correlates with reduced heart function and suboptimal portovenous contrast phase. Patients who underwent portovenous abdominal CT using bolus-tracking and echocardiography within 2weeks were included and excluded if there was a non-standard contrast injection. The bolus trigger time (BTT) at 100 Hounsfield units in the abdominal aorta, patient age, congestive heart failure (CHF) history, and ejection fraction were recorded. Two radiologists scored the liver contrast phase (1-5, 5 being an optimal portovenous phase). When applicable, the BTT and contrast score of the most recent comparison examination with equivalent technical parameters were also recorded. Simple linear regression (univariate) was used to test for associations with trigger time. 114 patients with a mean age of 61 ± 15years fulfilled criteria. The mean trigger time was 18 ± 6s (range: 6-38s) and the mean ejection fraction was 52 ± 12% (range: 19-69%). A longer bolus trigger had a significant correlation with reduced ejection fraction (P = 0.0018), lower hepatic contrast score (P < 0.0001), history of CHF (P = 0.0212), and older age (P = 0.0223). Contrast score differences between the study exam and available prior exams revealed score differences of 0 (n = 73), 1 (n = 15) and 2 (n = 5); these were associated, respectively, with a mean bolus trigger time difference between exams of 2s (range, 0-6s), 6s (range, 1-15s), and 11s (range, 5-13). The P-value comparing bolus trigger time and contrast score differences was less than 0.0001. A lower ejection fraction also significantly correlated with suboptimal PV contrast phase (P < 0.0001). Delayed time to trigger during bolus-tracking for CT can indicate cardiac dysfunction and may not adequately adjust to provide an optimal portovenous contrast phase.

Role of Computed Tomography Scan in the Assessment of Subacute Intestinal Obstruction at Bhuj, Kutch: A Prospective Study

Background: Bowel obstruction occurs when the normal flow of intraluminal contents is interrupted. Obstruction can be functional or due to a mechanical obstruction. Now a day’s CT is considered to be the most efficacious imaging technique for determining the cause of intestinal obstruction. However, the indications for the use of CT in patients with Sub-Acute Intestinal Obstruction (SAIO) have not been fully defined. Objectives of the present study are to study the role of CT in Diagnosis of patients with suspected subacute intestinal obstruction (SAIO), to find out site &amp; cause of obstruction and to diagnose complications of obstruction. Subjects and Methods: This study was conducted at Department of Radiodiagnosis, Gujarat Adani institute of Medcial Science, Bhuj, Kutch, Gujarat. Total number of 22 patients with SAIO having equivocal findings on USG was included in this study. Detailed clinical evaluation of the patients was done. Plain x-ray of abdomen in erect posture &amp; abdominopelvic ultrasound were performed before CT scan. CT scans were performed on a GE lightspeed VCT 64 slice scanner and acquired in precontrast &amp; portovenous phase at 60sec after i.v. contrast administration. Results: Age of the patients in the study range between 14 to 76 years. Out of 22 were 12 male &amp; 10 female patients. On CT scan all 22 patients were found to have obstruction with 19 patients having mechanical obstruction &amp; 3 patients having pseudo obstruction secondary to appendicitis, jejunal perforation. Most common cause of SAIO was ileal stricture 38% followed by intussusceptions 23%. Conclusion: CT is not only useful in distinguishing mechanical obstruction from paralytic ileus but also it often establishes the cause of obstruction &amp; presence of complications like strangulation &amp; perforation.

Hepatic sclerosing hemangioma mimics hepatic malignancies: a case report and multidisciplinary approach

BackgroundHepatic sclerosing hemangiomas (HSH) are rare benign vascular tumors that mimic radiologically hepatic malignancies. HSH is characterized by extensive fibrosis and hyalinosis as a result of degeneration and thrombosis. Pre-operative diagnosis is very difficult and most of the cases undergo surgical resections.Case presentationA 65 years old, hepatitis C virus-infected female presented by an accidentally discovered hepatic focal lesion. Magnetic resonance imaging (MRI) showed a T2 hyperintense mass displaying peripheral enhancement in porto-venous phase. The patient had a simultaneous typical hepatic hemangioma and multiple vertebral bodies’ hemangiomata. Tissue-guided biopsy revealed a densely sclerotic stroma containing vascular spaces with occasional obliteration of the lumen. Immunohistochemical staining was performed for Pan CK, CD34, SMA, VEGF, and c-Kit which confirmed the vascular nature of neoplasm and the involuting phase of hemangioma development. The patient was reassured and recommended for a regular radiological follow-up to reassess the lesion size.ConclusionThe definitive preoperative diagnosis of HSH is still problematic. However, the awareness of surgeons by this entity, peripheral enhancement in porto-venous phase on dynamic MRI, the presence of simultaneous typical hepatic hemangioma in the absence of cancer history could raise suspicion for HSH. Liver biopsy is still the gold standard in approaching the accurate diagnosis.

CT attenuation values and mineral distribution can be used to differentiate dogs with and without gallbladder mucoceles.

Gallbladder mucoceles are potentially fatal in dogs. Multiphase CT angiography was performed to evaluate the canine gallbladder in three conditions: no sludge, sludge occupying ≥25% of the lumen, and mucoceles. Twenty dogs with normal hepatobiliary bloodwork and no-to-minimal gallbladder sludge, 13 dogs with normal bloodwork and ≥25% sludge in the gallbladder lumen, and 18 dogs with histologically confirmed gallbladder mucoceles were enrolled in a prospective, observational diagnostic accuracy study. Three regions of interest (ROI) were stratified in the dorsal-ventral orientation and a single ROI was measured within the hepatic parenchyma. Mean attenuation and presence of mineral were recorded. Average Hounsfield units (HU) were recorded for precontrast, arterial, portovenous, and late venous phases. The overall median HU value for mucoceles was significantly higher than gallbladders without sludge and with sludge; precontrast median overall attenuation was 49.3, 35.8, and 39.7 HU, respectively (P<.000004). Mineral was seen in four (20%) dogs with no sludge, seven (56%) dogs with sludge, and nine (50%) dogs with mucoceles. Mineral in the dogs with mucoceles was located within the central aspect of the gallbladder lumen in 67% of mucoceles; this mineral distribution was not seen in any dog without a mucocele. Computed tomography can differentiate a subset of gallbladder mucoceles from dogs with and without gallbladder sludge, especially in the precontrast series. An HU value of 48.6 is 52% sensitive and 96% specific for a gallbladder mucocele. A hyperattenuating gallbladder on precontrast CT images and centrally distributed mineral can be a gallbladder mucocele.

A rare cause of upper gastrointestinal bleeding in pregnancy

A 29-year-old 11-week pregnant multigravida woman without previous medical history presentedwith sudden onset of hematemesis. This case illustrates the occurrence of a rare complication (rupture of pseudoaneurysm of right hepatic artery inside the biliary system), appearing as upper gastrointestinal bleeding in a pregnant woman. The cause of the rupture is presumably pregnancy-related. We would like to emphasize the presence of pseudoaneurysm of the hepatic artery as a rare cause of gastrointestinal bleeding in pregnancy.&#x0D; &#x0D; Figure 1 and 2 CTA showed a lobulated contour of saccular aneurysmal dilatation at proximal right hepatic artery, measured about 3.5x3.2x1.6 cm in size and 2.6 mm in neck width; pseudoaneurysm is likely. There is perianeurysmal heterogeneously hyperdense non-enhancing lesion which shows flip-flop phenomenon, measured about 5.5x6.1x5.5 cm in size; Partially thrombosed pseudoaneurysm at proximal right hepatic artery is likely. This lesion causes stretching of the common hepatic artery and portal vein. Hyperdenselesion with flip-flop phenomenon is also seen within dilated bilateral IHD, CHD, CBD and gallbladder; Contrast extravasation into CHD, CBD, 1st, 2nd, 3rd, 4th part of duodenum and jejunum is detected in portovenous phase. hemobilia is suggested.&#x0D;

Differentiation of Malignant from Benign Portal Vein Thrombi on CT Images Using Thrombus Density

AbstractBackground: Portal vein thrombosis described as the presence of a clot in the portal vein lumen or a permanent obliteration of the portal vein as a result of prior thrombosis with replacement by numerous tortuous venous channels (termed cavernoma). Malignant portal vein thrombus, so named for its neoplastic origin, is a common complication of HCC, and, in some cases, it may be even the initial sign of an undetected HCC. Detection of malignant PVT in a patient with liver cirrhosis heavily affects the therapeutic strategy.Aim of Study: The purpose of this study was to investigate the role of CT thrombus density (measured in Hounsfield Units) in distinguishing between neoplastic and bland portal vein thrombosis on arterial and portal venous phases.Material and Methods: In this study, 30 patients underwent contrast-enhanced CT of abdomen & pelvis were included for characterization of portal vein thrombosis. Assessment of portal vein thrombosis was performed by measuring of CT attenuation values of the thrombi in Hounsfield Units (HU).ROC (Receiver Operating Characteristic) curves were used to identify accuracy and optimal cutoff values.Results: Of the 30 CT studies, 14 neoplastic thrombi and 13 bland thrombi were identified on the images. CT thrombus density (measured in Housinfield Unit) to differentiate neo-plastic from bland thrombus. The AUCs was 0.98 in arterial phase and 0.98 in portovenous phase for thrombus density.The optimal cut off in arterial phase is 47 and in porto-venous phase is 50.Conclusion: CT attenuation values allow reliable differ-entiation between neoplastic and bland thrombi on arterial and portal venous phase CT examination.

Myasthenia Gravis as a Presenting Feature in a Patient With Hepatocellular Carcinoma: A Case Report

Myasthenia gravis (MG) as a presenting feature of extrathymic tumors are rarely reported. Here, we present a case of hepatocellular carcinoma (HCC) presented with MG. A 66-year-old Thai man presented to King Chulalongkorn Memorial hospital in September 2017 with weakness of his neck and legs. He also had trouble in swallowing and his voiced changed. The severity of those symptoms varied during a day while progressed over the past six months. Physical examination revealed weakness of neck muscle and the proximal muscle of extremities. Fatigability and enhanced ptosis were also observed. Electromyography showed a reproducible decremental response with repetitive nerve stimulation. High level of AChR-IgG (17.9 nmol/L) was compatible with a diagnosis of MG. The chest CT revealed no thymoma. However, the abdominal CT (figure 1) showed cirrhotic features with a 5.1x3.1 cm arterial enhancing and rapid venous washout mass in hepatic segment VIII invading segmental branches of right portal vein, representing the typical radiologic characteristics of HCC. The alpha-fetoprotein was 455 IU/mL. Serum immunologic test were negative for hepatitis B and C. The controlled attenuation parameter measured by transient elastography was 271 dB/m. The final diagnosis was fatty liver with cirrhosis grading Child-Pugh class A with HCC Barcelona Clinic Liver Cancer (BCLC) stage C and MG. The weakness improved after a treatment with intravenous immunoglobulin. Other medications were oral prednisolone 30 mg/d and pyridostigmine 240 mg/d which could be gradually tapered over time. Meanwhile, HCC was treated with two sessions of transarterial radioembolization (TARE) with Yttrium-90. The follow-up abdominal MRI (figure 2), 6 weeks after the 2nd TARE, demonstrated a decrease in size of both the HCC and the tumor thrombus in right portal vein. Several studies have been reported a high incidence of extrathymic malignancies with or without thymoma in MG patients, especially in the older age group. The pathophysiologic mechanism, even inconclusive, is suggested to be a paraneoplastic syndrome. However, there is no association between MG and any specific cancers. Approximately ten percent of these malignancies, with a rare report of HCC, present simultaneously with the MG. This case could be considered as the paraneoplastic MG, as an initial presentation, in a patient with advanced stage HCC. However, their associations require further investigations.2405_A Figure 1. The axial view of abdominal CT showed a 5.1x3.1 cm hypodensity mass in hepatic segment VIII (figure 1A; white arrow) with arterial enhancement in the arterial phase (figure1B) and rapid washout in the portovenous and delay phase (figure 1C and 1D, respectively) representing a typical radiologic features of HCC according to AASLD criteria.2405_B Figure 2. The axial view of the follow-up abdominal MRI (T1 dynamic phase) showed a decrease in size of HCC, 1.4x2.2 cm, in hepatic segment VIII (figure 2A; white arrow) without arterial enhancement in the arterial phase (figure 2B), representing responsiveness after TARE. Ring enhancement was observed in the portovenous and delay phase (figure 2C and 2D, respectively) representing fibrous tissue following TARE.

The Acute Blood Loss Anemia Mystery

Presentation and outcomes related to hepatocellular carcinoma (HCC) tumor rupture vary greatly. We present a unique case of spontaneous rupture of HCC. A 64 year-old male with history of HCV cirrhosis, ascites, portosystemic encephalopathy, esophageal varices, presented with worsening weakness, lethargy, and gait instability. On presentation, he was alert and oriented with dry mucous membranes, scleral icterus, a mildly distended non-tender abdomen, trace bilateral lower extremity edema, without asterixis. The patient was hemodynamically stable and labs showed hemoglobin (hb) 12.0 g/dL, platelet 47 k/uL, INR 1.6, and ammonia 148 umol/L. Treatment was initiated with fluids and lactulose for volume depletion and grade I hepatic encephalopathy (HE). An IR-guided diagnostic paracentesis was negative for SBP. Few days later, the patient developed hypotension with a drop in Hb to 6.5 g/dL without overt GI bleeding. After transfusion, an EGD showed portal hypertensive gastropathy, and three columns of non-bleeding grade II varices that were prophylactically banded. Five days later, patient again became hypotensive with worsening HE, hyperkalemia, elevated creatinine and severe anemia (hb 4.7 g/dL), still without overt evidence of GI bleeding. Urgent diagnostic ultrasound guided paracentesis was consistent with hemoperitoneum. Emergent CTA (Figures 2, 3) revealed a 3.1 x 3.7cm exophytic lesion in the right hepatic lobe, with high density within, suggesting spontaneous rupture of HCC with active extravasation and intra-peritoneal hemorrhage. IR obtained hemostasis with gelfoam embolization of the right hepatic branches. Transplant hepatology service deemed the patient not to be a candidate due to risk of HCC seeding from ruptured tumor. HCC related mortality is commonly due to tumor progression and liver failure. The overall risk of spontaneous HCC tumor rupture is relatively low (3-30%), but with very high mortality risk (20-70%). Risk factors for rupture include hypertension, cirrhosis, portal hypertension, portal vein thrombosis and tumor location, size, and degree of extra-hepatic protrusion. Improved survival rates can be seen after embolization and radical resection. The patient's history, presentation, and recurrent acute unexplained anemia with overt GI bleed put him at high risk of tumor rupture. This case highlights the progression of HCC leading to hemorrhagic shock from a ruptured exophytic lesion in the setting of decompensated cirrhosis.2291_B Figure 2. CTA, arterial phase, with arrow pointing to exophytic liver lesion now measuring 3.1 x 3.7 cm compared to prior CT. There is high density within it equaled to the density within the hepatic vessels suggesting spontaneous rupture of hepatocellular carcinoma with active extravasation.2291_C Figure 3. CTA, Portovenous phase, arrow points to liver lesion.2291_A Figure 1. CT imaging 2-months prior to presentation with cirrhotic and shrunken liver. Arrow points to stable 2.3 cm exophytic mass arising from the lateral right hepatic lobe. There are small hypodense foci throughout the liver, too small to access.

Stromal Content Is Correlated With Tissue Site, Contrast Retention, and Survival in Pancreatic Adenocarcinoma.

Desmoplastic stroma is a cardinal feature of primary pancreatic ductal adenocarcinoma (PDAC), but its effects on the biology, prognosis and therapeutic outcomes are not known. We developed an automated method to assess tumor stroma density (TSD) and investigated computed tomography (CT)-correlates of stroma in PDAC. We collected PDAC samples from rapid autopsy and resection series and digitally annotated samples to quantify TSD. A series of resected patients also underwent preoperative multiphasic CT. Automated and manual assessments of TSD were highly correlated (ρ= 0.65, P < 0.001). Solid organ metastases had a lower median TSD than primary tumors (P < 0.001). Patients with high TSD enjoyed prolonged recurrence free survival (RFS) (P = 0.003; HR = 0.51) and overall survival (P = 0.008, HR = 0.57). In another independent dataset, patients with high TSD had decreased risk for recurrence (P = 0.003, HR = 0.03) and death (P = 0.003, HR = 0.03) at time of resection, however the protective effect diminished over time. Patients with normalized portovenous phase CT tumor enhancement ratio ≥0.40 had a longer RFS following resection (P = 0.020). Normalized portovenous phase CT tumor enhancement ratio was significantly correlated with TSD (P = 0.003). Objective quantitative assessment of stroma in PDAC revealed several clinically relevant observations. Firstly, stroma was less abundant in metastatic PDAC, the cause of most PDAC mortality. Secondly, high stromal content correlates with favorable outcome in resected cases, implying a protective effect of stroma and suggesting careful consideration of active stromal depletion therapies. Finally, standard multiphase CT imaging correlates with stroma content as well as clinical outcome, indicating that non-invasive assessment of stroma is a feasible sensitivity enrichment approach in PDAC.

Bosniak category III renal lesions: likelihood of malignancy based on computed tomography findings.

IntroductionBosniak introduced a classification of renal cysts based on imaging characteristics. Cystic renal changes are categorized determining their risk of malignancy and further management. However, defining the malignancy of category III lesions still remains a challenge and our aim was to evaluate the features of malignancy in computed tomography within this category.Material and methodsThe Vilnius University Hospital Santariškių Klinikos information system was retrospectively searched for computed tomography examinations in which Bosniak category III lesions were reported. Data of genetic disorders and history of malignancy were collected. Longest diameter, location, shape, amount and location of calcification, contrast enhancement of Bosniak category III lesions were evaluated. The relation between collected data and malignancy was estimated.RESULTSThere were 73 patients with Bosniak category III lesions included and 43 cysts were surgically removed and histologically analyzed. Mean tumor size was significantly lower in malignant lesions. Mean enhancement in arterial and portovenous phase, change of mean enhancement in portovenous and native phases were significantly different between benign and malignant lesions. Significant differences in the contrast enhancement pattern was found: septa and capsular enhancement was detected in 28.6% (n = 12) of cases in malignant lesions, while only 4.8% (n = 2) benign lesions show the same enhancement pattern. Some other features showed tendencies to be more prevalent in malignant lesions, however, no significant differences were found.ConclusionsThe collected data and selected features do not allow us to reliably differentiate Bosniak category III cystic lesions as benign or malignant. Some of the criteria showed some tendencies, however, further studies are required to confirm these findings' potential.

Computed Tomography in the Detection Hepatic Calcification Hemangioma

The purpose: the estimation of a computed tomography(CT) signs of hepatic calcification hemangioma. Material and methods. Retrospectively results of CT with bolus contrast enhancement for examination hepatic calcified lesions of the 36 patients were analyzed. Results. As a basis for the retrospective analysis, the semiotic signs of patients, in which the hemangioma calcification developed during the dynamic CT monitoring, were used. As shown by the analysis, the center of calcification in combination with the cloisonne structures leading the arterial vessel, the decrease in the area of the focal lesion in the portovenous phase due to the vascular structures along the periphery of the focus are the criteria of calcified hemangioma. In 11 of 36 patients, calcified foci in the liver turned out to be hemangiomas.Conclusion. More than 30% calcifications in the liver detected at CT can be calcification hemangioma.

Validated preoperative computed tomography risk estimation for postoperative hepatocellular carcinoma recurrence.

AIMTo develop and validate a risk estimation of tumor recurrence following curative resection of operable hepatocellular carcinoma (HCC).METHODSData for 128 patients with operable HCC (according to Barcelona Clinic Liver Cancer imaging criteria) who underwent preoperative computed tomography (CT) evaluation at our hospital from May 1, 2013 through May 30, 2014 were included in this study. Follow-up data were obtained from hospital medical records. Follow-up data through May 30, 2016 were used to retrospectively analyze preoperative multiphasic CT findings, surgical histopathology results, and serum α-fetoprotein and thymidine kinase-1 levels. The χ2 test, independent t-test, and Mann-Whitney U test were used to analyze data. A P-value of < 0.05 was considered statistically significant.RESULTSDuring the follow-up period, 38 of 128 patients (29.7%) had a postoperative HCC recurrence. Microvascular invasion (MVI) was associated with HCC recurrence (χ2 = 13.253, P < 0.001). Despite postoperative antiviral therapy and chemotherapy, 22 of 44 patients with MVI experienced recurrence after surgical resection. The presence of MVI was 57.9% sensitive, 75.6% specific and 70.3% accurate in predicting postoperative recurrence. Of 84 tumors without MVI, univariate analysis confirmed that tumor margins, tumor margin grade, and tumor capsule detection on multiphasic CT were associated with HCC recurrence (P < 0.05). Univariate analyses showed no difference between groups with respect to hepatic capsular invasion, Ki-67 proliferation marker value, Edmondson-Steiner grade, largest tumor diameter, necrosis, arterial phase enhanced ratio, portovenous phase enhanced ratio, peritumoral enhancement, or serum α-fetoprotein level.CONCLUSIONNon-smooth tumor margins, incomplete tumor capsules and missing tumor capsules correlated with postoperative HCC recurrence. HCC recurrence following curative resection may be predicted using CT.

Nutmeg liver.

Nutmeg liver refers to the mottled appearance of the liver as a result of hepatic venous congestion. Radiologically, it is most appreciable on portovenous phase imaging on cross-sectional imaging. It is named after the cut appearance of the nutmeg seed.

Effect of non-alcoholic liver disease on recurrence rate and liver regeneration after liver resection for colorectal liver metastases.

Resection of metastases is the only potential cure for patients with liver metastasis from colorectal cancer (crc-lm). But despite an improved overall 5-year survival, the recurrence rate is still as high as 60%. Non-alcoholic fatty liver disease (nafld) can decrease the liver's capacity to regenerate after resection and might also affect cancer recurrence, potentially by elevating transforming growth factor β, levels of specific metalloproteinases, and oxidative stress. The objective of the present work was to determine the effect of the histologic features of nafld on cancer recurrence and liver regeneration. This retrospective analysis considered 60 patients who underwent an R0 hepatectomy for crc-lm. Volumetric analysis of the liver was calculated using axial view, portovenous phase, 2.5 mm thickness, multiphasic computed tomography images taken before and after surgery. The histologic features of nafld (steatosis, inflammation, and ballooning) were scored using the nafld activity score, and the degree of fibrosis was determined. The hepatic recurrence rate was 38.33%. Median overall survival duration was 56 months. Median disease-free survival duration was 14 months, and median hepatic disease-free survival duration was 56 months. Multivariate analysis revealed significant correlations of hepatic disease-free survival with hepatocyte ballooning (p = 0.0009), lesion diameter (p = 0.014), and synchronous disease (p = 0.006). Univariate and multivariate analyses did not reveal any correlation with degree of steatosis or recurrence rate. This study reveals an important potential negative effect of hepatocyte ballooning on hepatic disease-free survival.

Body composition measurement using computed tomography: Does the phase of the scan matter?

The aim of this study was to determine, from the methodologic standpoint, the effect of the presence or absence of intravenous contrast on body composition variables obtained by analysis of computed tomography (CT) images. Triphasic abdominal (noncontrast, arterial phase, and portovenous phase contrast) CT scans from 111 patients were analyzed by two independent assessors at the third lumbar vertebral level using SliceOmatic software (version 5.0, TomoVision, Montreal, Canada). Variables included skeletal muscle index (SMI), fat and fat-free mass (FM and FFM, respectively), and mean skeletal muscle Hounsfield units (SMHU). Mean SMHU was lowest in the noncontrast phase (29.4, standard deviation [SD] 8.9 HU), followed by arterial (32.4, SD 9.3 HU) then portovenous phases (34.9, SD 9.4 HU). The mean skeletal muscle attenuation was significantly different depending on the phase of the scan in which the images were obtained. Calculated FM was significantly lower in both arterial (28.6, SD 8.8kg, P<0.0001) and portovenous phase scans (28.5, SD 8.9kg, P<0.0001) when compared with noncontrast (29.2, SD 8.9kg). The mean FFM was not significantly different as measured on noncontrast, arterial, or portovenous phase CT scans (48, SD 11.2; 48.1, SD 9.8; and 48.6, SD 10.2kg, respectively). No difference was seen in SMI. Interobserver reliability was high. The definition of myosteatosis should include a standardized phase of CT for analysis and this should be incorporated within its definition. However, as the magnitudes of the differences were relatively small, the effect of the phase of the scan on predicting outcome needs to be determined.

MRI and CT into Pathology Tumor and Liver Bile Duct

Background: Tumor pathologies of the liver and bile ducts are relatively commonly diagnosed and the primary goal is to differentiate these lesions in the fastest possible time which determines the apropriate method of treatment. Aims and Objectives: Aim of this study is tracking and diagnostic imaging correlation of tumor pathologies of liver and bile ducts and determining the early diagnostic approach. Data obtained from this study are important for treatment procedures and succes of treatment. All cases with liver tumor pathologies from period 2012-2016 were examined with CT and MRI followed by other complementary imaging methods. Methods: CT examination was performed according to standard triple-phase protocol: non-enhanced phase, arterial phase and porto-venous phase, and in some cases with late phase after 5 minutes. In MRI examinations, standard protocol was performed: coronal T2 single-shot fast spin-echo (coronal T2 SSFs), Axial T2 respiratory-triggered fast spin-echo (axial T2-FRE)/or breath-hold fast-recovery fast spin-echo T2 body coil sizes XL, (axial T2-FRFSE-XL), Axial in-phase/out-of-phase, Axial/ coronal three-dimensional liver acquisition with volume acceleration (3D coronal pre lava). Results: For comparation, only patients with liver focal lesions were included in the study, and and patient were examined with both diagnostic imaging modalities (CT and MRI). 168 patients with liver tumor pathologies and biliary tree tumor pathologies are included in the study. Gender ratio was 85 males and 83 female (M/F ratio 1.03:1). Average age of patients was 58.41 years, (minimum age 1.5 years old and maximum 88 years of age). The most frequent age on diagnosis was 61 - 70 years (total of 49 patients or 29.16%). Benign tumors were found with 93 patients (55.35%) and malignant tumors in 79 patients (47.02%). Distribution in liver parenchyma was found in 113 patients (67.26%), while in 49 patients (29.17%) pathology was found in the biliary tract. The most affected liver segment was the fifth segment in 35 patients (20.83%), while the less affected segment was the second liver segment in 8 patients (4.73%). most of patients (62 patients or 36.90%) had more than two affected segments in time of diagnosis. Diagnostic criteria in this study require further future evaluation. Conclusion: Early diagnosis of are tumors remains a real challenge and has great impact in the survival rate of patients. Finally, our study showed that for our country’s institutions that there was no significant difference between both CT and MRI modalities in liver focal lesions assessment.

Feasibility of triphasic CT with a modified two-point Patlak plot to determine spit kidney glomerular filtration rate in clinical practice.

To investigate whether triphasic CT with a simplified Patlak plot can be used in clinical practice for the estimate of split kidney glomerular filtration rate (SKGFR). The animal experiment included 15 rabbits that underwent 40 dynamic contrast-enhanced CT scans of the kidneys with 1.5s time interval. Patlak-derived SKGFR was obtained using standard forty-point, two-point (unenhanced phase, arterial phase t α, and portovenous phase t β), and a modified two-point (MTP) (unenhanced, t α, t β, and a virtual t τ [t τ=(t α+t β)/2]) image data, respectively. The MTP-Patlak plot approach was then validated in 13 patients who underwent a triphasic renal contrast-enhanced CT examination. SKGFR measured by 99mTc-DTPA clearance was as a standard reference. MTP-Patlak significantly reduced input function errors than two-point Patlak (21.1±16.2% vs 30.8±15.2%, p<0.01) and showed good concordance with standard Patlak for measurement of SKGFR in animal experiment (1.20±0.38mL/g/min vs 1.51±0.43mL/g/min; linear correlation coefficient r=0.87, p<0.001). Human study showed that mean SKGFR was 45.7mL/min (range, 26.5-86.2mL/min) obtained from 99mTc-DTPA, and 38.2mL/min (range, 18.6-79.3mL/min) obtained from triphasic CT using MTP-Patlak plot. Linear correlation between the two methods was r=0.75 (p<0.01). The mean difference between SKGFRs as determined with the two methods was 7.4±9.0mL/min. The MTP-Patlak approach, featured with simplicity, is feasible in a clinically indicated CT examination for the evaluation of split renal function.

Fast and accurate liver volumetry prior to hepatectomy

BackgroundVolumetric assessment of the liver is essential in the prevention of postresectional liver failure after partial hepatectomy. Currently used methods are accurate but time-consuming. This study aimed to test a new automated method for preoperative volumetric liver assessment. MethodsPatients who underwent a contrast enhanced portovenous phase CT-scan prior to hepatectomy in 2012 were included. Total liver volume (TLV) and future remnant liver volume (FRLV) were measured using TeraRecon Aquarius iNtuition® (autosegmentation) and OsiriX® (manual segmentation) software by two observers for each software package. Remnant liver volume percentage (RLV%) was calculated. Time needed to determine TLV and FRLV was measured. Inter-observer variability was assessed using Bland-Altman plots. ResultsTwenty-seven patients were included. There were no significant differences in measured volumes between OsiriX® and iNtuition®. Moreover, there were significant correlations between the OsiriX® observers, the iNtuition® observers and between OsiriX® and iNtuition® post-processing systems (all R2 > 0.97). The median time needed for complete liver volumetric analysis was 18.4 ± 4.9 min with OsiriX® and 5.8 ± 1.7 min using iNtuition® (p < 0.001). ConclusionBoth OsiriX® and iNtuition® liver volumetry are accurate and easily applicable. However, volumetric assessment of the liver with iNtuition® auto-segmentation is three times faster compared to manual OsiriX® volumetry.

Parametric response mapping of contrast-enhanced biphasic CT for evaluating tumour viability of hepatocellular carcinoma after TACE.

To determine the feasibility and role of parametric response mapping (PRM) for quantitative assessment of regional contrast-enhancement patterns in hepatocellular carcinoma (HCC). Biphasic CT of 19 patients receiving repetitive conventional transarterial chemoembolisation (cTACE) for intermediate stage HCC were retrospectively analysed at baseline and follow-up at 3, 6, and 9months. Voxel-based registration of arterial and porto-venous phases, with segmentation of the largest target lesion was performed. Frequency distribution plots of density-pairs of segmented voxels were generated. To differentiate necrotic, hypervascular and non-hypervascular tumour, and lipiodol/calcification, thresholds of 30, 100, and 300 HU were applied. Changes in density frequency plots over time were analysed and compared to response and assessment criteria (WHO, RECIST, EASL, mRECIST) and survival. PRM was feasible in all cases. Tumour volumes and hypervascular/non-hypervascular volume ratio showed significant longitudinal decrease (p < 0.05). Hypervascular volume at baseline was inversely correlated to survival (R = -0.57, p = 0.005). The only predictive parameter following cTACE to show significant survival difference was the change of the viable/non-viable ratio (p = 0.044), whereas common response assessment criteria showed no significant difference in survival. PRM allows a quantitative and more precise assessment of regional tumour vascularisation patterns and may be helpful for TACE treatment planning and response assessment. • PRM allows more precise assessment of tumour vascularisation compared to conventional evaluation • PRM is beneficial for cTACE treatment planning and response assessment • PRM allows a quantitative assessment of regional contrast enhancement patterns.

Split bolus technique in polytrauma: a prospective study on scan protocols for trauma analysis.

For the evaluation of severely injured trauma patients a variety of total body computed tomography (CT) scanning protocols exist. Frequently multiple pass protocols are used. A split bolus contrast protocol can reduce the number of passes through the body, and thereby radiation exposure, in this relatively young and vitally threatened population. To evaluate three protocols for single pass total body scanning in 64-slice multidetector CT (MDCT) on optimal image quality. Three total body CT protocols were prospectively evaluated in three series of 10 consecutive trauma patients. In Group A unenhanced brain and cervical spine CT was followed by chest-abdomen-pelvis CT in portovenous phase after repositioning of the arms. Group B underwent brain CT followed without arm repositioning by a one-volume contrast CT from skull base to the pubic symphysis. Group C was identical to Group A, but the torso was scanned with a split bolus technique. Three radiologists independently evaluated protocol quality scores (5-point Likert scale), parenchymal and vascular enhancement and artifacts. Overall image quality was good (4.10) in Group A, more than satisfactory (3.38) in Group B, and nearly excellent (4.75) in Group C (P < 0.001). Interfering artifacts were mostly reported in Group B in the liver and spleen. In single pass total body CT scanning a split bolus technique reached the highest overall image quality compared to conventional total body CT and one-volume contrast CT.