Comparison between CT volumetry and extracellular volume fraction using liver dynamic CT for the predictive ability of liver fibrosis in patients with hepatocellular carcinoma.

OBJECTIVES: To compare the predictive ability of liver fibrosis (LF) by CT-volumetry (CTV) for liver and spleen and extracellular volume fraction (ECV) for liver in patients undergoing liver resection. METHODS: We retrospectively analysed 90 consecutive patients who underwent CTV and ECV. Manually placed region-of-interest ECV (manual-ECV), rigid-registration ECV (rigid-ECV), and nonrigid-registration ECV (nonrigid-ECV) were calculated as ECV(%) = (1-haematocrit) × (ΔHUliver/ΔHUaorta), where ΔHU = subtraction of unenhanced phase from equilibrium phase (240 s). Manual-ECV was compared with CTV for the estimation of LF. The total liver volume to body surface area (TLV/BSA), splenic volume to BSA (SV/BSA), ratio of TLV to SV (TLV/SV), ratio of right liver volume to SV (RV/SV), and liver segmental volume ratio (LSVR) were measured. ROC analyses were performed for ECV and CTV. RESULTS: After excluding 10 patients, seventy-eight (97.5%) out of 80 patients had a Child-Pugh score of 5 points, and two (2.5%) patients had a Child-Pugh score of 6 points. AUC of ECV showed no significant difference among manual-ECV, rigid-ECV, and nonrigid-ECV. TLV/BSA, SV/BSA, TLV/SV, and RV/SV had a higher correlation with LF grades than manual-ECV. AUC of SV/BSA was significantly higher than that of manual-ECV in F0-1 vs F2-4 and F0-2 vs F3-4. AUC of SV/BSA (0.76-0.83) was higher than that of manual-ECV (0.61-0.75) for all LF grades, although manual-ECV could differentiate between F0-3 and F4 at high AUC (0.75). CONCLUSIONS: In patients undergoing liver resection, SV/BSA is a better method for estimating severe LF grades, although manual-ECV has the ability to estimate cirrhosis (≥ F4). KEY POINTS: The splenic volume is a better method for estimating liver fibrosis grades. The extracellular volume fraction is also a candidate for the estimation of severe liver fibrosis.

Isolated Arteries Originating from the Intrahepatic Arteries: Anatomy, Function, and Importance in Intervention.

Isolated hepatic arteries are defined as hepatic terminal arterioles that are not accompanied by portal venules or bile ductules and penetrate the liver parenchyma and distribute to the hepatic capsule and intrahepatic hepatic veins. Abundant communications exist between intra- and extrahepatic arteries through isolated arteries and capsular arterial plexus. They play a principal role in the development of subcapsular hemorrhage and arterial collateral formation following transcatheter arterial chemoembolization for liver cancers. The anatomy, function, and clinical importance of isolated hepatic arteries in interventional radiology, especially regarding subcapsular hemorrhage and arterial collateral formation, are highlighted in this article.

Protective effect against repeat adverse reactions to iodinated contrast medium: Premedication vs. changing the contrast medium.

OBJECTIVES: The purpose of this study was to assess the protective effect of premedication and changing contrast media (CM) against repeat adverse reactions (ARs) to iodinated CM. METHODS: Between January 2006 and September 2014, 771 cases with previous ARs to CM were administered CM. The same CM that had caused ARs previously was administered to 491 cases (220 without premedication [defined as the control group], and 271 with premedication [the premedication alone group]). A different CM from the previous CM was given to 280 cases (58 without premedication [the changing CM alone group], and 222 with premedication [the premedication and changing CM group]). RESULTS: The control group had 61 repeat ARs (27.7%). The premedication alone group had 47 ARs (17.3%, p<0.01). The changing CM alone group had 3 ARs (5.2%, p<0.001). Three ARs (7.9%) were observed in 38 cases changing from one to another low-osmolar nonionic CM. Twenty cases with previous ARs to the high-osmolar CM and to the low-osmolar ionic CM showed no ARs. The premedication and changing CM group had 6 ARs (2.7%, p<0.001). CONCLUSION: Premedication prior to contrast for patients with previous ARs may be protective, however, changing CM was more effective. KEY POINTS: • In patients with previous adverse reactions, changing contrast media is recommended. • Premedication is unnecessary against previous reactions to high-osmolar or ionic CM. • Changing from one to another low-osmolar non-ionic CM may be effective.

Spatial anatomy of the round ligament, gallbladder, and intrahepatic vessels in patients with right-sided round ligament of the liver.

PURPOSE: To analyze the vascular structure of the liver in patients with a right-sided round ligament. METHODS: We reviewed 16 patients with a right-sided round ligament and 3 polysplenia and situs inversus patients with a left-sided round ligament who underwent multidetector row CT with contrast media. The patient population consisted of 13 men and 6 women (mean 62 years). We analyzed the axial and volume-rendered images for the location of the round ligament, gallbladder, portal veins, hepatic veins, and hepatic artery. The following imaging findings for the patients with polysplenia and situs inversus were horizontally reversed. RESULTS: The prevalence of a right-sided round ligament with and without polysplenia was 75 and 0.11 %, respectively. The gallbladder was located to the right, below, and left of the round ligament in 27.7, 38.8 and 33.3 %, respectively. Independent branching of the right posterior portal vein was noted in 57.8 %. PV4 was difficult to identify in 36.8 %. The middle hepatic vein was located to the left of the round ligament. Two branching patterns for the lateral and medial branches of the right anterior hepatic artery were noted: the common (44.4 %) and separated types (55.5 %). Both of the right anterior hepatic artery and portal vein ramified into two segments; the lateral segment with many branches and the medial segment with a few branches. CONCLUSIONS: The right-sided round ligament divided the right anterior section into the lateral and medial segments based on the portal vein and hepatic artery anatomy.

An analysis of initial and follow-up CT findings in intramural hematoma, aortic double-lumen dissection, and mixed type lesions.

BACKGROUND: Although the clinical presentation of intramural hematoma (IMH) and aortic double-lumen dissection (AD) is similar, the imaging results and subsequent clinical course of the two lesions differ. PURPOSE: To compare the clinical and radiological findings of IMH, AD, and mixed type lesions. MATERIAL AND METHODS: Forty-two patients with IMH, 38 with AD, and 10 with mixed type lesions were imaged with post-contrast-enhanced CT. The most proximal ulcer-like lesions and entry tears and the distal ends of the IMH and AD were evaluated. The interval change of the intramural hematoma, ulcer-like lesion, and false lumen was observed. The pathological findings of the aorta were evaluated in 15 patients. RESULTS: The most proximal ulcer-like lesion and entry tear were located in the arch to the descending aorta in 27 (64.2%) of the 42 patients with IMH and in 24 (63.1%) of the 38 patients with AD. The distal extension was located at the iliac arteries in six (14.3%) patients with IMH and in 31 (81.6%) patients with AD (P < 0.001). The intramural hematomas regressed in 29 (93.5%) of 31 patients, and the ulcer-like lesion progressed in 14 (70%) of 20 patients with IMH. The clinical features of the mixed type lesions resembled those of AD, rather than IMH. The intramural hematoma or dissection was observed within the outer media in all lesion types on histopathology. CONCLUSION: There is a distinct difference between IMH and AD in distal extension; however, the locations of the lesions are pathologically the same in the media of the aorta.

Spatial relationship between the hepatic artery and portal vein based on the fusion image of CT angiography and CT arterial portography: the left hemiliver.

OBJECTIVE: The objective of our study was to clarify the hepatic artery anatomy of the left hemiliver using the fusion image of CT angiography (CTA) and CT arterial portography. MATERIALS AND METHODS: CTA and CT arterial portography were performed on a 64-MDCT scanner in 144 patients. All images were transferred to a workstation for 3D analysis using the multiimage fusion mode. We classified the left hepatic artery (LHA) and middle hepatic artery (MHA) as type L when only the LHA was present, type MB when a medial branch from the LHA was present, type LM when both the LHA and MHA were present, and type M when only the MHA was present. The hepatic artery was classified into infraportal and supraportal groups on the basis of its relationship with the laterosuperior branch of the left portal vein. We also classified the branching pattern of the arteries to each segment. Pattern 1 was defined as when the LHA divided into the laterosuperior segment artery (A2), which then divided into the lateroinferior segment artery (A3) and medial segment artery (A4). Pattern 2 was defined as when the LHA divided into A3, which then divided into A2 and A4. Pattern 3 was defined as when the LHA divided into A4, which then divided into A2 and A3. Pattern 4 was defined as when the LHA divided into A2, A3, and A4 simultaneously. RESULTS: The prevalence of each type was as follows: type L (n = 37, 25.7%), type MB (n = 44, 30.6%), type LM (n = 53, 36.8%), and type M (n = 6, 4.2%). The number of cases classified as infraportal was 54 (37.5%) and supraportal, 73 (50.7%). The cases classified by branching pattern were as follows: pattern 1, 26 cases (18.0%); pattern 2, eight (5.6%); pattern 3, 93 (64.5%); and pattern 4, 13 (9.0 %). CONCLUSION: Three-dimensional fusion images based on CTA and CT arterial portography can show the various anatomic patterns of the left hemiliver hepatic artery in relation to the left portal vein.

Multidetector CT anatomy of drainage routes of gastric varices: a pictorial review.

Most gastric varices arise at hepatofugal collateral pathways and drain into the systemic vein through one or both of two different types of portosystemic collateral drainage systems: the gastroesophageal (azygous) venous system and the gastrophrenic venous system. The gastroesophageal venous system consists of gastric varices contiguous with esophageal varices, paraesophageal varices, and the azygos vein, which terminates into the superior vena cava. Gastric varices draining through the gastroesophageal venous system can be treated with endoscopic techniques or creation of a transjugular intrahepatic portosystemic shunt. The gastrophrenic venous system consists of the gastric varices and the left inferior phrenic vein (IPV), which terminates into the left renal vein or the inferior vena cava. The left IPV has abundant anastomoses with peridiaphragmatic and retroperitoneal veins, and these anastomoses can function as drainage pathways from gastric varices. Balloon-occluded retrograde transvenous obliteration is a preferred treatment option for this type of gastric varix. Occasionally, gastric varices can form at the hepatopetal collateral pathway that develops secondary to localized portal hypertension caused by splenic vein occlusion. Splenectomy is often required for the treatment of this type of gastric varix. Multidetector computed tomography permits comprehensive evaluation of these venous drainage systems. Familiarity with and assessment of these draining routes of gastric varices are important for selecting treatment options and interventional techniques.

Anatomy of right superior septal artery demonstrated on the coronary CT scan.

BACKGROUND: A coronary CT scan allows for non-invasive visualization of the anatomy of a coronary artery in three dimensions compared to the two dimensions afforded by conventional angiography. The septal artery, the main blood source of the interventricular septum, is usually derived from the left anterior descending artery; however, it is occasionally derived from the right coronary artery. PURPOSE: To analyze the prevalence, origin, diameter, and length of the right superior septal artery (RSSA) demonstrated on a coronary CT scan. MATERIAL AND METHODS: The right superior septal artery was retrospectively reviewed on the reconstructed axial scan images (0.5-mm thickness, 0.25-mm interval) in 1290 consecutive patients who underwent coronary CT scans. All patients were scanned on a 320-row CT scanner. The images were transferred to a workstation to trace the vessel to analyze the origin, diameter, and length. We also compared the length of the RSSA between patients with and without coronary artery stenosis. RESULTS: The RSSA was identified in 51 (3.9%) of 1290 patients. The origin was the proximal portion of the right coronary artery (n = 40) or the right sinus of Valsalva (n = 11). The artery co-existed with the conus artery in 15 (29%) of 51 patients. The length was 16-62 mm (mean 31.2 mm ± 10.5), and the diameter was 0.8-2.0 mm (mean 1.3 mm ± 0.2). Longer RSSAs tended to be demonstrated in the patients with coronary artery stenosis rather than with normal coronary arteries (P < 0.05). CONCLUSION: The right superior septal artery and its anatomical variant could be analyzed with a coronary CT scan. The ability to demonstrate this artery on the coronary CT scan was the same as with coronary angiography. The recognition of this vessel is useful for physicians managing with the diagnosis and treatment of the coronary artery disease.

A proposed model on MR elastography for predicting postoperative major complications in patients with hepatocellular carcinoma.

OBJECTIVE: To develop a model for predicting post-operative major complications in patients with hepatocellular carcinoma (HCC). METHODS: In all, 186 consecutive patients with pre-operative MR elastography were included. Complications were categorised using Clavien‒Dindo classification, with major complications defined as ≥Grade 3. Liver-stiffness measurement (LSM) values were measured on elastogram. The indocyanine green clearance rate of liver remnant (ICG-Krem) was based on the results of CT volumetry, intraoperative data, and ICG-K value. For an easy application to the prediction model, the continuous variables were converted to categories. Moreover, logistic regression analysis and fivefold cross-validation were performed. The prediction model's discriminative performance was evaluated using the area under the receiver operating characteristic curve (AUC), and the calibration of the model was assessed by the Hosmer‒Lemeshow test. RESULTS: 43 of 186 patients (23.1%) had major complications. The multivariate analysis demonstrated that LSM, albumin-bilirubin (ALBI) score, intraoperative blood loss, and ICG-Krem were significantly associated with major complications. The median AUC of the five validation subsets was 0.878. The Hosmer-Lemeshow test confirmed no evidence of inadequate fit (p = 0.13, 0.19, 0.59, 0.59, and 0.73) on the fivefold cross-validation. The prediction model for major complications was as follows: -2.876 + 2.912 [LSM (>5.3 kPa)]+1.538 [ALBI score (>-2.28)]+0.531 [Intraoperative blood loss (>860 ml)]+0.257 [ICG-Krem (<0.10)]. CONCLUSION: The proposed prediction model can be used to predict post-operative major complications in patients with HCC. ADVANCES IN KNOWLEDGE: The proposed prediction model can be used in routine clinical practice to identify post-operative major complications in patients with HCC and to strategise appropriate treatments of HCC.

Predictive value of combined computed tomography volumetry and magnetic resonance elastography for major complications after liver resection.

PURPOSE: To retrospectively compare the predictive value of computed tomography volumetry (CTV), magnetic resonance elastography (MRE) of the liver, and their combination for major complications after liver resection. METHODS: We enrolled 108 consecutive patients who underwent anatomical liver resection for liver tumors and preoperative contrast-enhanced CT and MRE. The future liver remnant (FLR) ratio was calculated by CTV, while the liver stiffness measurement (LSM) was obtained by MRE. FLR ratio alone, LSM alone, and combined FLR ratio and LSM were evaluated to predict major complications (Clavien-Dindo grade ≥ IIIa). Univariate and multivariate analyses of hepatic biochemical parameters and imaging data were performed to identify predictors of major complications. Receiver operating characteristic analyses of FLR ratio, LSM, and their combination were performed, and the sensitivity and specificity were calculated. RESULTS: Twenty-two (20.4%) of the 108 patients experienced major complications. According to multiple regression analysis, the FLR ratio (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.91-0.99, p = 0.040) and LSM (OR 1.72, 95% CI 1.01-2.94, p = 0.047) were independent predictors of major complications. The combined FLR ratio and LSM were predictive of major complications, with an area under the curve (AUC) of 0.818, sensitivity of 68.2%, and specificity of 84.9%. The AUC and specificity for combined FLR ratio and LSM were larger than those for FLR ratio (AUC: 0.711, specificity: 80.2%) and LSM (AUC: 0.793, specificity: 80.2%). CONCLUSION: Combined CTV and MRE analysis can improve the AUC and specificity for predicting major complications after anatomical liver resection.

Air embolism and needle track implantation complicating CT-guided percutaneous thoracic biopsy: single-institution experience.

OBJECTIVE: The objective of our study was to present the details and incidence of air embolism and needle track implantation in patients who underwent percutaneous CT-guided thoracic biopsy. MATERIALS AND METHODS: We retrospectively reviewed 1,400 percutaneous CT-guided thoracic biopsies during the period from August 1993 to August 2008. A case with air embolism was considered to be a patient with hypotension during or after biopsy and with an air embolism confirmed on CT. A needle track implantation was considered to be a mass in the needle track on the postbiopsy follow-up CT. RESULTS: There were three (0.21%) cases of air embolism. Air embolisms were confirmed in the left ventricle, coronary artery, ascending aorta, and pulmonary vein. The pulmonary venous wall was pathologically identified in one case. Although there were no fatalities, two patients needed resuscitation. Left hemiplegia occurred in one case, but it gradually disappeared. There were four (0.56%) cases of needle track implantation in 713 pathologically proven malignant thoracic biopsy cases with follow-up CT scans. Two were primary lung cancer and the others were lung metastasis (renal cell carcinoma and osteosarcoma). Implantation was found 4-7 months (mean, 5.6 months) after the biopsy, and size was 2.5-5.6 cm (mean, 3.5 cm). CONCLUSION: The incidence of air embolism with clinical symptoms and needle track implantation complicating percutaneous thoracic biopsy is more frequent than the previously reported rate.

The hepatic capsular arteries: imaging features and clinical significance.

BACKGROUND: Although the anatomical features of the hepatic capsular arteries have been previously reported, the radiological and clinical importance of these arteries has not been well documented. IMAGING FINDINGS: We injected barium sulfate into the intra- and extra-hepatic arteries in cadavers to investigate the hepatic capsular arteries. The web-like hepatic capsular arteries derived from the capsular branch of the peripheral hepatic arteries are called isolated arteries. There were anastomoses between the intra- and extra-hepatic arteries (inferior phrenic artery, superior falciform ligament artery, and cystic artery) through the hepatic capsular arteries. CLINICAL SIGNIFICANCE: We reviewed the radiology database and assessed clinical cases. When the hepatic artery is occluded, the collateral vessels, such as the inferior phrenic artery and the superior falciform ligament artery, develop via the hepatic capsular arteries at the right triangular ligament and falciform ligament, respectively. Bleeding from capsular arteries causes extensions of the subcapsular hematoma. CONCLUSION: The hepatic capsular arteries spread along the hepatic surface and constitute the vascular network throughout the liver. These arteries play an important role in collateral circulation in various clinical situations, as well as subcapsular hematoma.

The left inferior phrenic artery arising from left hepatic artery or left gastric artery: radiological and anatomical correlation in clinical cases and cadaver dissection.

BACKGROUND: The purpose of this study is to assess angiographic and CT appearance of left inferior phrenic artery (LIPA) arising from left hepatic or left gastric artery and to recognize its specific anatomical location with the help of cadaver dissection. METHODS: We retrospectively reviewed 761 abdominal angiographies and found 13 patients (1.7%) with LIPA arising from left hepatic or left gastric artery. We classified those origins and assessed radiological features. We also presented a cadaver dissection to identify anatomical location of LIPA arising from left hepatic artery. RESULTS: The origin of the LIPA was classified as follows: (a) left hepatic artery: four, (b) accessory left gastric artery: one, (c) accessory left hepatic artery: three, and (d) left gastric artery: five patients. The proximal portion was located in gastrohepatic ligament and its distal portion was located in front of esophageal hiatus. In a cadaver dissection, the proximal portion ascends along ligamentum venosum and distal portion courses along superior aspect of left hemi diaphragm in front of esophagus. CONCLUSION: The LIPA rarely arises from left hepatic or left gastric artery. The proximal portion was located in gastrohepatic ligament and the distal portion runs in front of the esophageal hiatus.

Relative atherosclerotic plaque volume by CT coronary angiography trumps conventional stenosis assessment for identifying flow-limiting lesions.

The new methods for diagnosing the ischemia with coronary computed tomographic angiography (CTA) as a noninvasive test have been investigated. To compare the relative plaque volume to quantitative CTA and quantitative coronary angiography (QCA) for detecting flow-limiting coronary artery stenoses. We studied 49 patients with 55 intermediate lesions (30-69% diameter stenosis) who underwent CTA, coronary angiography (CAG), and FFR. CTA and QCA measures included lesion length, percent diameter stenosis (%DS), minimal lumen diameter (MLD), target main vessel percent plaque volume (%PV), lesion %PV, target main vessel percent lumen volume (%LV), and lesion %LV. FFR ≤0.80 was considered diagnostic of a flow-limiting lesion. The area under the receiver-operating characteristic curve (AUC) was used to determine the accuracy of detecting flow-limiting lesions. We also investigated the AUC of discrimination of flow-limiting lesion according to calcium score. Eighteen of 55 lesions (32.7%) had an FFR ≤0.80. Only vessel %PV differentiated between lesions with and without flow obstruction (67.6 vs. 62.7%, p = 0.018). The AUC for vessel %PV was greatest (0.76; 95% CI 0.61-0.87). The AUC for the discrimination of the flow-limiting lesions according to low calcium score (≤400) improved to 0.82 (95% CI 0.57-0.94). In intermediate coronary artery stenoses, vessel %PV is more accurate than conventional stenosis assessment for detecting flow-limiting lesions. In low calcium score, vessel %PV is more useful for diagnosis of ischemic heart disease compared with conventional quantitative measures.

Prevalence and sonographic detection of Chilaiditi's sign in cirrhotic patients without ascites.

OBJECTIVE: Although Chilaiditi's sign is uncommon, its recognition is mandatory to avoid intestinal injury during percutaneous transhepatic procedures. Our purpose was to investigate the prevalence of Chilaiditi's sign in cirrhotic patients without ascites and to review the diagnostic ability of sonography to detect this rare abnormality. CONCLUSION: The prevalence of Chilaiditi's sign was much higher in cirrhotic patients without ascites than in the general population. A precise diagnosis of Chilaiditi's sign was possible using sonography. Percutaneous transhepatic procedures can be performed safely if a route that avoids the intestine is found.

The vascular anatomy of the ligaments of the liver: gross anatomy, imaging and clinical applications.

The vessels that communicate between the liver and adjacent structures require bridges between them. The bridges comprise the ligaments of the liver as follows: the falciform ligament, right and left coronary ligaments, lesser omentum including the hepatogastric ligament and hepatoduodenal ligament. Each ligament has specific communications between the intrahepatic and extrahapetic vessels. The venous communications called as the portosystemic shunt would become apparent in patients with portal hypertension, intrahepatic portal vein thrombosis and superior vena cava syndrome. The location of the venous communication is related to the pseudolesion or focal enhancement of the liver demonstrated on the CT scan. The arterial communications called collateral vascularization would become apparent in patients with hepatic artery occlusion, especially post-transhepatic arterial embolization, or in patients with the hepatic tumour abutting diaphragm. The knowledge of these collateral arteries is necessary to accomplish the effective transarterial embolization for the hepatic tumours. We reviewed the vessels in these ligaments using contrast-enhanced CT scans and angiography and discussed the clinical applications. Cadaver dissection photos were included as supplementary images for readers to recognize the actual spatial anatomy of the vessel in each ligament.

Analysis of the caudate artery with three-dimensional imaging.

BACKGROUND/PURPOSE: To date there have been only a few radiological studies of the caudate artery. This study aimed to precisely analyze the caudate artery as well as the relationship between the caudate arteries, the arterial plexus at the hilar plate, and the hilar bile duct. METHODS: Reconstructed three-dimensional (3D) computed tomography images from 50 patients during hepatic arteriography were analyzed. The caudate arteries were classified as right branches (Irs) or left branches (Ils). The communicating artery (CA) was defined as the artery connecting the right, left, segmental, and common hepatic arteries. RESULTS: The caudate artery was divided into 3 types: an independent branch (Type 1); the common tract formed by Ir and Il (Type 2); and an arterial branch from the CA (Type 3). The CA was recognized in 25 of 50 patients. There was a total of 65 arteries to the hilar bile duct observed in 40 patients, and 24 (37 %) of these 65 arteries to the hilar bile duct originated from the caudate artery or CA. CONCLUSION: The caudate artery plays an important role not only in connecting the blood supply of the right and left livers but in the blood supply to the hilar bile duct.

Spatial relationship between intrahepatic artery and portal vein based on the fusion image of CT-arterial portography (CTAP) and CT-angiography (CTA): new classification for hepatic artery at hepatic hilum and the segmentation of right anterior section of the liver.

PURPOSE: To clarify the variations of the intrahepatic artery and portal vein and to verify the proper segmentation for the right anterior section of the liver. MATERIALS AND METHODS: CT during arterial portography and CT angiography were performed on 64-slice multi detector row CT in 147 patients. All images were transferred to a workstation for analysis using multi-image-fusion mode. We investigated the spatial relationship between hepatic artery and portal vein in the right hemiliver and the segmentation of the right anterior hepatic artery and portal vein. RESULTS: The spatial anatomy of right hepatic arteries and portal vein was (1) anterior and posterior hepatic artery run superior and inferior to anterior portal vein, respectively (47.6%), (2) one anterior hepatic artery runs superior to and another one runs inferior to anterior portal vein (15%), (3) anterior and posterior hepatic arteries run superior to anterior portal vein (11.6%), (4) anterior and posterior hepatic arteries run inferior to anterior portal vein (7.5%), and (5) one posterior hepatic artery runs superior to and another one runs inferior to anterior portal vein (6.8%). The combined anatomy of right anterior artery and portal vein with regard to segmentation was classified as (1) dorso-ventral (26.5%), (2) dorso-ventral and inferior (10.9%), (3) multiple (18.4%), and (4) superior and inferior segments (1.4%). CONCLUSION: There are various types of spatial anatomy of intrahepatic artery and portal vein. The hepatic arteries as well as portal veins of right anterior section of the liver could be divided into dorsal and ventral, not superior and inferior.