Aberrant course of the left gastric vein in the human. Possibility of a persistent left portal vein

Multiple portal veins in the hepatoduodenal ligament: Evidence of "duodenal reverse rotation" hypothesis?

Duplication of the portal vein is a rare variation, and reports of this condition are quite limited. The present report describes a woman of advanced age who was incidentally diagnosed with duplicated portal veins. The portal vein from the splenic vein distributed to the left lobe of the liver, and that from the superior mesenteric vein ran between the pancreas and duodenum to distribute to the right lobe. The former portal vein connected with the round ligament, and its presumptive origin was the left vitelline vein. The latter was presumably from the right vitelline vein. Between the 2 portal veins, 2 anastomotic veins were identified; one anastomosis was posterior to the pancreatic head, and the other was intrahepatic. The common bile duct was located posterolateral to the portal veins. The relationships of these veins to the round ligament and common bile duct support the reverse rotation hypothesis of the duodenum in the development of portal vein variations.

Aberrant right gastric vein mimicking hepatic spread of prostate cancer on PSMA-PET/CT

Hepatic vasculature can exhibit a wide variety of variants, some of which may resemble pathologic findings. In this case, a 53-year-old man presenting for staging of biochemically recurrent prostatic adenocarcinoma was found to have focally increased prostate-specific membrane antigen (PSMA) tracer uptake on positron emission tomography (PET) imaging in hepatic segment IV. This finding was initially concerning for hepatic metastasis of the patient's primary prostate adenocarcinoma. However, the area of radiotracer uptake was not associated with a discrete lesion on CT, and the geographic morphology of the uptake raised the possibility of a vascular etiology. Magnetic resonance imaging (MRI) of the liver showed no hepatic metastases and confirmed the presence of an aberrant right gastric vein directly perfusing the corresponding portion of hepatic segment IV. This case highlights PSMA uptake in the liver secondary to vascular variants as a potential mimic for metastatic disease on PSMA-PET/CT.

Hepatic pseudolesions caused by alterations in intrahepatic hemodynamics

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

Aberrant gastric venous drainage and associated atrophy of hepatic segment II: computed tomography analysis of 2021 patients

PURPOSE

To investigate the prevalence and patterns of aberrant gastric venous drainage and associated atrophy of the hepatic segment on contrast-enhanced computed tomography (CT).

METHODS

Two radiologists retrospectively reviewed contrast-enhanced CT images from 2021 patients who underwent cone-beam CT-guided chemoembolization between January 2013 and December 2018. They determined the presence or absence of an aberrant gastric vein(s) and its drainage site by consensus, and qualitatively analyzed the presence or absence of atrophy of segments II or III. In cases of disagreement between the two reviewers regarding the presence of atrophy, quantitative analysis was performed using dedicated software.

RESULTS

A total of 31 aberrant right gastric veins were revealed on CT (1.5%), most of which drained into P2 (n = 8), the S2/3 border zone (n = 8), S2 (n = 6), or S4 (n = 5). An aberrant left gastric vein was observed in 21 (1.0%) patients, and P2 was the most common drainage site (n = 13) in these patients. Atrophy of segment II was more frequently observed among patients with aberrant gastric veins than among those without (26.9% versus 4.1%; p < 0.001). In addition, an aberrant gastric vein draining into P2 was most frequently accompanied by segment II atrophy (47.6%).

CONCLUSION

Aberrant right and left gastric veins were observed in 1.5% and 1.0% of patients, respectively. Atrophy of segment II was frequently observed in patients with aberrant gastric veins, especially those that drained into P2.

Novel technique for pediatric living donor liver transplantation in patients with portal vein obstruction: The "pullout technique"

PV hypoplasia may increase the risk of posttransplant complications, especially when it extends to near the SMV and SpV junction. We described our experience of 10 pediatric cases of PV hypoplasia/thrombus in which the pullout technique was required for PV reconstruction. There were five male and five female patients. The median age was 9 months, and the median weight was 8.1 kg. The indications for the pullout technique were PV hypoplasia in seven patients and PV thrombus in 3. The inflow sites of the enlarged LGV were as follows: the main PV trunk (n = 2), the SMV and SpV junction (n = 4), and the SpV (n = 4). The posterior face of the pancreas was tunneled along the PV, and the PV was returned to its original position with or without the use of an interposed vein graft. The pullout technique created a good operative field, which allowed for the complete removal of the hypoplastic PV or thrombectomy with the safe use of various interposed vein grafts.

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.

Strategic approach to concurrent aberrant left gastric vein and aberrant left hepatic artery in laparoscopic distal gastrectomy for early gastric cancer: A case report

An aberrant left gastric vein (ALGV) directly entering the lateral segment of the liver is a rare variation in the portal vein system, whereas an aberrant left hepatic artery (ALHA) arising from the left gastric artery is observed relatively frequently. Here we report a case in which both ALGV and ALHA were encountered before laparoscopic distal gastrectomy with curative lymphadenectomy for gastric cancer. We accurately diagnosed these vessel anomalies preoperatively on abdominal contrast-enhanced CT. During surgery, we divided the ALGV at the point of entry to the liver and preserved the ALHA by dividing the branches toward the stomach, in consideration of curability and safety. The postoperative course was uneventful overall, although temporary mild liver dysfunction was observed. This case highlights the importance of preoperative evaluation and preparation in a rare case of concurrent ALGV and ALHA.

Left gastric vein on the dorsal side of the splenic artery: a rare anatomic variant revealed during gastric surgery

Purpose

The left gastric vein (LGV) is an important blood vessel requiring dissection during gastric surgery. We describe a rare anatomic variant of the LGV.

Methods

The LGV drainage pattern was analyzed relative to intraoperative vascular anatomy in 2,111 patients with gastric cancer who underwent radical resection from May 2007 to September 2012. The incidence of the anatomic variant was determined, and the diameter and length of the LGV and the distances from the end of the LGV to the splenoportal confluence and the root of the left gastric artery (LGA) were measured by abdominal CT reconstruction.

Results

In 6 of the 2,111 (0.28 %) gastric cancer patients who underwent radical resection, the LGV descended on the left side of the gastropancreatic fold, ran across the dorsal side of the splenic artery and drained into the splenic vein. The mean diameter and length of the LGV were 5.10 ± 0.40 and 37.40 ± 5.19 mm, respectively, and the mean distance from the end of the LGV to the splenoportal confluence was 13.05 ± 0.86 mm. The closer the LGV and LGA were to the root, the greater the distance between them, with a mean 13.85 ± 1.02 mm between the end of the LGV and the root of the LGA.

Conclusions

In this rare anatomic variant, the LGV descends along the gastropancreatic fold, runs across the dorsal side of the splenic artery and drains into the splenic vein. Knowledge of this rare anatomic variant will help avoid damage to the LGV during gastric surgery.

Right gastric venous drainage: angiographic analysis in 100 patients

Objective

To evaluate the pattern of right gastric venous drainage by use of digital subtraction angiography.

Materials and Methods

A series of 100 consecutive patients who underwent right gastric arteriography during transcatheter arterial chemoembolization for hepatocellular carcinoma were included in this study. Angiographic findings were retrospectively analyzed with respect to the presence or absence of the right and aberrant gastric veins, multiplicity of draining veins, aberrant right gastric venous drainage sites, and the termination pattern of aberrant right gastric veins (ARGVs). We also compared the relative size of the right and left gastric veins.

Results

A total of 49 patients collectively had 66 ARGVs. The common drainage sites for the ARGVs included the hepatic segment IV (n = 35) and segment I (n = 15). The termination pattern of ARGV could be classified into 4 different types. The most common type was termination as a superficial parenchymal blush formation in small areas without demonstrable portal branches. A statistically significant difference was found for the dominancy of the right gastric vein in gastric venous drainage between the two groups with or without ARGV (p < 0.05, Fisher's exact test). In the group of patients without ARGV (n = 51), the right gastric vein was equal to (n = 9) or larger than (n = 17) the left gastric vein in 26 patients (26 of 51, 51%).

Conclusion

The incidence of ARGV is higher than expected with four distinct types in its termination pattern. The right gastric vein may play a dominant role in gastric venous drainage.

Analysis of focal spared areas in fatty liver using color Doppler imaging and contrast-enhanced microvessel display sonography

OBJECTIVE

The purpose of this study was to investigate whether focal fatty sparing (FFS) formation in the liver relates to aberrant blood flow.

METHODS

Sixty-three FFSs of the liver in 52 patients were examined by color Doppler flow imaging and contrast-enhanced microvessel display sonography. The 63 FFSs included 16 FFSs in the porta hepatis, 14 FFSs around the gallbladder fossa, and 33 other FFSs. The control group included patients with a diagnosis of fatty liver but no FFSs or focal lesions near the porta hepatis.

RESULTS

Fourteen of 16 FFSs in the porta hepatis showed venous blood toward those areas that were differentiated from the portal and hepatic veins. Focal fatty sparings in the hilus hepatis correlated with aberrant veins, having a statistical significance compared with the control group (P < .0001). Seven of 14 FFSs around the gallbladder fossa contained blood vessels, 5 of them veins and the remaining 2 arteries. Two FFSs were located around hemangiomas. Three FFSs were located around maldeveloped vessels.

CONCLUSIONS

The blood supply to an FFS in the porta hepatis may be correlated with aberrant veins. Focal fatty sparings around the gallbladder fossa may be associated with aberrant blood flow.

Perigastric vascular abnormalities and the impact on esophagogastrectomy

The surgeon's ability to recognize abnormal vascular anatomy has greater importance than ever in modern esophagogastric surgical procedures. Some aberrations of vascular vessels around the stomach found during extensive surgery due to primary cancer of the stomach, cardia and lower esophagus are presented in this paper. The purpose of the prospective study is to evaluate and classify these variations with respect to their impact in visceral surgery. A total of 426 patients who underwent total or extensive gastrectomy and esophagectomy combined with lymphadenectomy, have been analyzed prospectively. For the period of 10 years some vascular aberrations have been found in 54/426 (12.67%) of the patients in the operative field during lymphadenectomy as single or combined anomalies. An arterial perigastric anatomy considered normal in textbooks was found in 372 (87.32%) cases. An accessory left hepatic artery arising from the left gastric artery was found in 19/54 (35.18%), and replaced type in 7/54 (12.96%). The replaced right hepatic artery branching from the superior mesenteric artery was found in 5/54 (7.40%) cases. Replaced and accessory left gastric artery branching from the aorta was found in 8/54 (14.8%); accessory posterior gastric artery was found in 25/54 (44.4%), and abnormalities of the splenic, and subphrenic arteries were found in 6/54 (11.11%). Combined anomalies of both left and right hepatic arteries and variations of the celiac trunk were found in 2/54 (3.70%) cases. Forty-nine cases were classified according to established Michels' typology system. Six cases presented with extremely rare variations and remain unclassified. Possible intraoperative problems concerning postoperative complications are also emphasized.

Accessory Left Gastric Artery from Left Hepatic Artery Shown on MDCT and Conventional Angiography: Correlation with CT Hepatic Arteriography

OBJECTIVE

The objective of our study was to evaluate the diagnostic accuracy of MDCT and conventional angiography in the detection of an accessory left gastric artery using CT hepatic arteriography as the standard of reference.

MATERIALS AND METHODS

The study group consisted of 118 patients who underwent MDCT with a triple-phase liver protocol with a slice thickness of 5 mm, conventional angiography, and CT hepatic arteriography. The early-phase images of MDCT and conventional angiography were retrospectively reviewed. The presence or absence of an accessory left gastric artery was evaluated using CT hepatic arteriography as the standard of reference. The sensitivity, specificity, and accuracy of MDCT and conventional angiography were calculated.

RESULTS

CT hepatic arteriography revealed an accessory left gastric artery in 25 (21.2%) of 118 cases, including 15 proximal- and 10 distal-type accessory left gastric arteries. On MDCT, there were seven false-negative cases and one false-positive case. Six of the seven false-negative cases were a proximal-type accessory left gastric artery, and nine of 10 distal-type accessory left gastric arteries were correctly diagnosed using MDCT. The sensitivity, specificity, and accuracy of MDCT were 72.0%, 98.9%, and 93.2%, respectively. On conventional angiography, there were three false-negative and two false-positive cases, none of whom underwent selective left hepatic arteriography. Two of the three false-negative cases were the distal-type accessory left gastric artery, but eight of the 10 distal-type accessory left gastric arteries were correctly diagnosed. The sensitivity, specificity, and accuracy of conventional angiography were 88.0%, 97.8%, and 95.8%, respectively.

CONCLUSION

Approximately 70% of accessory left gastric arteries can be diagnosed at the early phase of MDCT even with a slice thickness of 5 mm.

Portal vein occlusion with aberrant left gastric vein functioning as a hepatopetal collateral pathway

A rare case of an aberrant left gastric vein functioning as a hepatopetal collateral as a result of portal vein occlusion is presented herein. The portal venous phase of multislice computed tomography clearly demonstrated this anatomic variation and provided a reliable vascular "road map" for percutaneous transhepatic portal venous stent placement. Portal hypertension associated with extensive gastrojejunal varices improved dramatically after stent placement.

Focal sparing of fatty liver in segment II associated with aberrant left gastric vein

We present a patient with aberrant left gastric vein (LGV) that directly enters the posterior edge of segment II in the liver. The corresponding area was focally spared of fatty liver. We consider that this aberrant LGV contributed to the cause of focal sparing. This is the first report of the use of helical CT and Doppler ultrasound to depict the aberrant LGV that directly enters the liver.

Concurrent aberrant right gastric vein directly draining into the liver and variations of the hepatic artery

We report an autopsy on a 46-year-old man, a case that presented the concurrence of two rare vascular variations of the lesser omentum: aberrant right gastric vein draining directly into the liver, and multiple hepatic arteries. Although the left gastric vein emptied into the left aspect of the portal vein, the right one was found to ascend from the gastric lesser curvature along the right aspect of the common bile duct and to reach directly the porta hepatis. A left hepatic artery originating from the left gastric artery entered the porta hepatis in conjunction with the left ramus of the portal vein. A predominant right hepatic artery arose from the superior mesenteric artery and entered the porta hepatis in conjunction with the right ramus of the portal vein. The proper hepatic artery originating from the celiac artery entered the porta hepatis in conjunction with the aberrant right gastric vein. The possibility of a common underlying mechanism for these rare vascular variations is discussed.

Simultaneous aberrant left and right gastric veins draining directly into the liver

Aberrant gastric veins draining directly into the liver are rare variations of the portal vein system. We report on an autopsy in which both right and left gastric veins drained directly into the liver without joining the portal vein. Although the left gastric artery adopted a standard disposition, the left gastric vein was indeed found to ascend from the lesser curvature through the upper part of the lesser omentum. After receiving branches from the gastroesophageal junction, it directly entered the left part of the porta hepatis. The right gastric vein ascended from the lesser gastric curvature along and in front of the right aspect of the common bile duct without ending in the portal vein. It crossed in front of the common hepatic duct and directly entered the porta hepatis. Careful dissection within the liver parenchyma showed that both gastric veins ended in the intra-hepatic part of the left branch of the portal vein. Although aberrant gastric veins are known variations of the portal vein system, the conjunction of both right and left gastric vein has never been reported. It highlights the possibility that the venous drainage of the gastric lesser curvature may be totally independent of the main portal vein.

Aberrant left gastric vein directly draining into the liver

An aberrant left gastric vein found in dissection is reported here. The right gastric vein did not exist and only the left gastric vein originating from the lesser curvature of the stomach was present. It directly entered the liver without typically joining the trunk of the portal vein. After giving off a small branch to the liver parenchyma, the left gastric vein merged into the left branch of the portal vein. This aberrant left gastric vein may correspond to the phylogenetic and ontogenetic "left portal vein." The aberrant left gastric vein is considered to play an important role as a portal collateral pathway of the portal system, which is critical not only in anatomy but also in clinical diagnosis.

Aberrant left gastric vein demonstrated by helical CT

PURPOSE

Our goal was to describe the CT findings of aberrant left gastric vein (ALGV) and to evaluate the clinical significance of this vein.

METHOD

Four patients in whom ALGVs were demonstrated by helical CT were examined. Each patient had either intrahepatic cholangiocarcinoma, cirrhosis with gastric varices, chronic hepatitis, or nonspecific abdominal pain. All patients underwent two phase helical CT, and the patient with cholangiocarcinoma underwent CT during arterial portography, and 3D images of the abdominal veins were obtained.

RESULTS

In all patients, the ALGVs ran along the hepatogastric ligament and were directly connected with the left portal branch. In the patient with cholangiocarcinoma, the portal vein had severe stenosis by tumor invasion, and both the ALGV and the aberrant right gastric vein functioned as a collateral pathway of the portal flow into the liver. In the patient with cirrhosis, dilated ALGV with hepatofugal flow caused gastric varices.

CONCLUSION

The ALGV is directly connected with the left portal branch and may play an important role in the collateral pathway of the portal system.

Ultrasound anatomy of the left gastric vein

A study of 187 consecutive patients undergoing upper abdominal ultrasound was conducted to evaluate the size and the ending of the left gastric vein (LGV) into the portal system and its relation to the coeliac axis and tributaries. The LGV was identified in 86 (46%) of these patients; the mean size of the LGV was 2.4 mm, 30% terminating in the portal vein, 33% at the splenoportal junction and 37% in the splenic vein. The LGV was anterior to the coeliac trunk and its branches in 45%, two thirds of these ending in the splenic vein and posterior in 51% of the cases, 86.3% of which ended at or to the right of the splenoportal junction. In conclusion, the variation in the site of termination of the LGV has a significant correlation with the course of the LGV in relation to the adjacent vessels. The LGV tends to cross superficial to the splenic artery when it enters the splenic vein and deep to the common hepatic artery when draining in the portal vein.

Angiographic demonstration of intrahepatic termination of left gastric vein: a venous anomaly

An unusual venous anomaly is reported. A digital subtraction visceral angiogram shows intrahepatic termination of the left gastric (coronary) vein draining into branches of the left portal vein.