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

Absent celiac trunk and unusual arterial anatomy of the upper abdomen: into the deep

The celiac trunk is the first major branch of the abdominal aorta. It originates from the ventral aspect of the aorta at the level of T12-L1 vertebrae and was originally described as an artery that branches into the common hepatic artery, left gastric artery, and splenic artery. Absence of the celiac trunk and origin of the three arteries separately from the aorta is a rare entity that is reported in 0.38% to 2.6% of cases. It is even more uncommon that this variation can be accompanied by other vascular variations of the upper abdomen as accessory arteries to the liver, stomach, and pancreas. These cases arise during embryogenesis due to decreased arterial degeneration combined with decreased arterial fusion, which results in the anatomical variations present in the current case. Complex arterial variations are both a risk for iatrogenic injury during surgical procedures and beneficial during endovascular supply as they may provide additional access for embolization and chemotherapy.

Accessory left gastric artery aneurysms in granulomatosis with polyangiitis: a case report and literature review

Aneurysm formation is a potential complication of granulomatosis with polyangiitis (GPA), previously known as Wegener’s granulomatosis. It is a very rare complication, but immediate diagnosis and therapy should be performed because an aneurysm can be life-threatening if it ruptures. An accessory left gastric artery (ALGA) is also a rare variant gastric artery that may obtain its blood supply from the left hepatic artery and left gastric artery. We herein describe a 57-year-old Japanese man who was diagnosed with GPA complicated by aneurysm rupture in an ALGA. Emergency surgery was performed after failure of arterial coil embolization to interrupt blood flow in the ALGA. The patient underwent partial resection of the lesser omentum, which contained all aneurysms. During partial resection of the lesser omentum, both the left gastric artery and ALGA were ligated because they were thought to be feeders of the aneurysms. Postoperative recovery was uneventful; no bleeding or recurrence of the aneurysms occurred. Immediate diagnosis and therapy should be performed for patients with GPA with symptoms of vascular ischemia or aortitis. Endovascular intervention is the first-choice therapy especially for hemodynamically stable patients with ruptured aneurysms or aneurysms located on variant arteries, which may have multiple blood supplies. In the present case, although endovascular treatment failed, the approach described herein was helpful during open surgery.

A Case of Unusual Vascularization of Upper Abdominal Cavity' Organs

We describe a case report of multiple arterial variations of internal organs of upper abdominal cavity in a cadaver of 63-year-old female. There were several developmental variations of the vascular supply of the stomach, pancreas, spleen, and liver. There were several accessory arteries: left gastric, left hepatic, and posterior gastric artery as well as several arteries that had abnormal origin. The variations were discovered during macroscopical dissection at the department of human anatomy. It should be noted that multiple developmental variation can be common in clinical practice and clinicians should be aware of them during diagnostic and interventional procedures.

Safety analysis of holmium-166 microsphere scout dose imaging during radioembolisation work-up: A cohort study

OBJECTIVE

Radioembolisation is generally preceded by a scout dose of technetium-99m-macroaggregated albumin to estimate extrahepatic shunting of activity. Holmium-166 microspheres can be used as a scout dose (±250 MBq) and as a therapeutic dose. The general toxicity of a holmium-166 scout dose (166Ho-SD) and safety concerns of an accidental extrahepatic deposition of 166Ho-SD were investigated.

METHODS

All patients who received a 166Ho-SD in our institute were reviewed for general toxicity and extrahepatic depositions. The absorbed dose in extrahepatic tissue was calculated on SPECT/CT and correlated to clinical toxicities.

RESULTS

In total, 82 patients were included. No relevant clinical toxicity occurred. Six patients had an extrahepatic deposition of 166Ho-SD (median administered activity 270 MBq). The extrahepatic depositions (median activity 3.7 MBq) were located in the duodenum (3x), gastric fundus, falciform ligament and the lesser curvature of the stomach, and were deposited in a median volume of 15.3 ml, which resulted in an estimated median absorbed dose of 3.6 Gy (range 0.3-13.8 Gy). No adverse events related to the extrahepatic deposition of the 166Ho-SD occurred after a median follow-up of 4 months (range 1-12 months).

CONCLUSION

These results support the safety of 250 MBq 166Ho-SD in a clinical setting.

KEY POINTS

• A holmium-166 scout dose is safe in a clinical setting. • Holmium-166 scout dose is a safe alternative for 99m Tc-MAA for radioembolisation work-up. • Holmium-166 scout dose potentially has several benefits over 99m Tc-MAA for radioembolisation work-up.

Extrahepatic Arteries Originating from Hepatic Arteries: Analysis Using CT During Hepatic Arteriography and Visualization on Digital Subtraction Angiography

PURPOSE

To investigate the prevalence and site of origin of extrahepatic arteries originating from hepatic arteries on early phase CT during hepatic arteriography (CTHA) was accessed. Visualization of these elements on digital subtraction hepatic angiography (DSHA) was assessed using CTHA images as a gold standard.

MATERIALS AND METHODS

A total of 943 patients (mean age 66.9 ± 10.3 years; male/female, 619/324) underwent CTHA and DSHA. The prevalence and site of origin of extrahepatic arteries were accessed using CTHA and visualized using DSHA.

RESULTS

In 924 (98.0%) patients, a total of 1555 extrahepatic branches, representing eight types, were found to originate from hepatic arteries on CTHA. CTHA indicated the following extrahepatic branch prevalence rates: right gastric artery, 890 (94.4%); falciform artery, 386 (40.9%); accessory left gastric artery, 161 (17.1%); left inferior phrenic artery (IPA), 43 (4.6%); posterior superior pancreaticoduodenal artery, 33 (3.5%); dorsal pancreatic artery, 26 (2.8%); duodenal artery, 12 (1.3%); and right IPA, 4 (0.4%). In addition, 383 patients (40.6%) had at least one undetectable branch on DSHA. The sensitivity, specificity, and accuracy of visualization on DSHA were as follows: RGA, 80.0, 86.8, and 80.4%; falciform artery, 53.9, 97.7, and 80.0%; accessory LGA, 64.6, 98.6, and 92.3%; left IPA, 76.7, 99.8, and 98.7%; PSPDA, 100, 99.7, and 99.9%; dorsal pancreatic artery, 57.7, 100, and 98.8%; duodenal artery, 8.3, 99.9, and 98.7%; and right IPA, 0, 100, and 99.6%, respectively.

CONCLUSION

Extrahepatic arteries originating from hepatic arteries were frequently identified on CTHA images. These arteries were frequently overlooked on DSHA.

The "Vessel through Strait" Sign is a Signature Radiological Sign for the Diagnosis of Left Hepatic Artery Variation

An aberrant artery (AA) can frequently be observed coursing through the fissure for the ligamentum venosum (FLV) which was termed the "vessel through strait" sign (VTSS) by us. Fundamental data including the incidence, anatomical composition and clinical significance of VTSS and the AAs composing VTSS are still lacking. We sought to give a systematic demonstration on this issue in the present study. VTSS was respectively analyzed in 2,275 patients and was observed in 357 of them. Interestingly, 319 (89.4%) out of the 357 patients exhibiting VTSS were proved to have left hepatic artery variation (LHAV) (247 with replaced left hepatic artery, 64 with accessory left hepatic artery and 8 with variant common hepatic artery). We therefore hypothesized that VTSS could be a sign that strongly associated with LHAV and could be used for its diagnosis. In the following validating analysis, VTSS gained a sensitivity of 96.3% and a specificity of 98.3% for the diagnosis of LHAV in another bicenter cohort consisted of 1,329 patients. In conclusion, VTSS is a signature radiological sign of LHAV which could be used as an easy and specific method for the diagnosis of LHAV.

The road less traveled: importance of the lesser branches of the celiac axis in liver embolotherapy

Effective treatment of unresectable hepatic neoplasms depends on the appropriate identification of tumor arterial supply. Because hepatic tumors derive more than 90% of their blood supply from the hepatic arteries, awareness of common hepatic arterial anatomic variants (e.g., replaced or accessory left or right hepatic artery), as well as parasitized collateral vessels originating from the celiac axis (e.g., right inferior phrenic, omental, and cystic arteries) that can supply hepatic neoplasms-particularly those with a surface location-is important for safe and effective interventional therapy for these tumors. Moreover, recognition of certain nonhepatic branches arising from the hepatic arterial circulation is important for optimizing transarterial therapy and blocking the passage of treatment particles into sensitive structures, thereby preventing unwanted clinical sequelae such as gastrointestinal ulceration, skin ulceration or pain, and, rarely, ischemic cholecystitis.

Chemoembolization of the left inferior phrenic artery in patients with hepatocellular carcinoma: 9-year single-center experience

OBJECTIVE

The purpose of this study was to evaluate retrospectively the radiologic findings and imaging response of hepatocellular carcinoma supplied by the left inferior phrenic artery.

MATERIALS AND METHODS

From January 2000 through December 2008, chemoembolization of the left inferior phrenic artery was performed on 152 patients (123 men, 29 women; mean age, 55.8 years) with hepatocellular carcinoma. The CT scans and digital subtraction angiograms of these patients were retrospectively reviewed in consensus by two investigators, who evaluated tumor location, tumor-feeding vessels, origin of the left inferior phrenic artery, technical success of chemoembolization, complications, and tumor response. Tumor response was assessed on the basis of the criteria of the European Association for the Study of the Liver.

RESULTS

Tumors supplied by the left inferior phrenic artery were located in Couinaud segment 2/3 (n = 100), segment 4 (n = 45), and other segments (n = 7). The most common tumor-feeding vessel was the anteromedial limb of the left inferior phrenic artery (n = 82) followed by the lateral limb (n = 40) and the anterior limb (n = 30). Selective chemoembolization via the left inferior phrenic artery was achieved in 58 of the patients (38%). Complete or partial response as detected on first follow-up CT images (mean follow-up time, 2.5 months) was achieved by 30 patients. In 33 patients in whom the tumor was supplied exclusively by the left inferior phrenic artery, the tumor response was more favorable in patients who underwent selective than in those who underwent nonselective chemoembolization via the left inferior phrenic artery (p = 0.028).

CONCLUSION

Selective chemoembolization via the left inferior phrenic artery is possible and results in good response of tumors supplied exclusively by the left inferior phrenic artery.

Sonographic anatomy of the gastrohepatic ligament

OBJECTIVE

The purpose of this presentation is to illustrate anatomic and pathologic features of the gastrohepatic ligament (GHL) and to show its usefulness for precise localization of abnormalities, particularly in relation to the lesser peritoneal cavity and diseases occurring within the confines of the ligament itself.

METHODS

Cases were selected that illustrate the objectives above.

RESULTS

Illustrations show various anatomic and pathologic features meant to enhance interpretation of left upper quadrant sonograms.

CONCLUSIONS

Illustrations seen in the sonographic literature vaguely interpret the relationships of the GHL. Misunderstanding has led not only to improper nomenclature but also to the use of inappropriate indicators of lesser omental diseases. With a clear understanding of the anatomy of the GHL and its use as a pivotal marker for structures around and within it, one can avoid these pitfalls and better evaluate adult and pediatric lesser omental anatomy.

Left inferior phrenic artery feeding hepatocellular carcinoma: angiographic anatomy using C-arm CT

OBJECTIVE

The left inferior phrenic artery (LIPA) is one of the common extrahepatic collateral arteries that supply hepatocellular carcinomas (HCCs). The purpose of this study is to describe the anatomy of the LIPA that supplies HCCs using C-arm CT in 23 patients.

CONCLUSION

The anteromedial limb of the ascending branch was present in 14 patients and accessory gastric branches were noted in 11 patients. The use of angiography and C-arm CT of the LIPA showed 26 tumor feeders in 23 patients. The feeders were seen in the anteromedial limb (n = 12), lateral limb (n = 9), anterior limb (n = 3), and descending branch (n = 2). The anteromedial limb of the ascending branch is a common tumor feeder of the LIPA and can supply HCCs located in the right liver dome. Gastric staining is also frequently depicted on LIPA angiography and should not be confused with tumor staining.

Anatomic variations of the hepatic arteries in 250 patients studied with 64-row CT angiography

The aim of our study was to determine the frequency of different hepatic arterial variants identified on abdominal CT angiography (CTA) with a 64-row CT system and a high resolution protocol. A total of 250 consecutive abdominal CTAs performed on a 64-row CT system were evaluated. Two radiologists in consensus analyzed arterial phase images; the anatomical findings were grouped according to Michels' classification. An anomalous arterial pattern was observed in 34% of the cases. The most common anomaly was Michels type III (9.2%), followed by types II and V (5.2%), type VI (4.0%), types IV, VII, and IX (2.0%), and type VIII (0.6%). No cases of type X were detected. Unclassified variations were observed in 3.3% of the cases. The new generation of 64-row MDCT allows optimal visualization of splanchnic vascular anomalies with a minimally invasive examination. This visualization is extended to those vessels with a small caliber and slow flow resulting in difficult recognition by classic angiographic studies. The knowledge of anomalous arterial patterns could be very useful in the preoperative planning of surgical and interventional liver procedures.

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.