Investigation of proper hepatic artery and gastroduodenal artery variations by multidetector computed tomography angiography method

Abstract

Purpose: The purpose of this study is to evaluate the clinical anatomic variations of the proper hepatic artery (PHA) and the gastroduodenal artery (GDA). For this purpose, angiographic images of patients were evaluated.

Materials and methods: We retrospectively reviewed the multiple-detector computed tomography angiography images of 671 patients.

Results: In this retrospective study, 35 different types were identified as associated with PHA and GDA. There were 292 patients (43.52%; 175 females and 117 males) included in normal anatomical classification. Different anatomic variations were detected in 300 patients (44.71%; 129 females and 171 males). In 79 patients, arterial branch follow-up failed. These patients were evaluated as an unidentified group.

Conclusion: We described different vascular variations in the PHAs and GDAs of our patients.     

复杂血管解剖的亲体肝脏移植手术

目的 探讨应用亲体肝脏移植手术克服肝脏移植手术供体短缺的方法。方法 对我院2001年11月12日至2001年12月13日进行的2例亲体肝脏移植手术后病人的情况进行总结，2例手术供体均有复杂的血管解剖变异。结果 2例接受亲体肝脏移植的患儿均顺利康复，术后1个月肝功能和胆红素水平均降至正常。无严重并发症发生。2例供体恢复顺利，无严重并发症。结论 亲体肝脏移植手术尽管可能由于解剖变异的原因造成手术困难，但仍然是克服儿童肝移植供体短缺的一种安全有效的方法。     

Imaging of pancreatic transplant vessels and anastomoses with 16-row multidetector computed tomography

The aim of this study was to evaluate the usefulness of 16-row multidetector computed tomography (16-MDCT) in the assessment of the potency of arterial and venous vessels in combined kidney-pancreas transplant and detection of transplant-related complications. Fifteen patients underwent a combined kidney-pancreatic transplantation. On the seventh day after the operation, we performed 16-MDCT in arterial and portal venous phase to evaluate vessels, anastomotic sites, and pancreatic parenchymal vascularization as well as peripancreatic fluid collections. We visualized the pancreatic vessels and anastomosis sites in all cases. In 12 recipients, there were no abnormal findings as regards the patency of the arterial and venous vessels and the vascularization of the pancreatic parenchyma. In two patients, complete arterial thrombosis of the body and tail pancreatic graft vessels was recognized at 2 weeks after transplantation, resulting in graft removal. Thrombi were localized in the distal part of anastomoses. None of the patients had venous thrombosis. One recipient had stenosis of the venous anastomosis. Peripancreatic fluid collections were observed in seven patients. In conclusion, 16-MDCT is an efficient method to estimate pancreatic transplant vessels, localize thrombi, and detect other transplant-related complications.     

Helical computed tomography angiography is the most efficient test to assess vascular calcifications in the iliac arterial sector in renal transplant candidates

The increased scope of renal transplant indications has lead to a larger number of recipients with vascular problems due to arterial calcifications in the iliac region. Compared to magnetic resonance and conventional arteriography, helical computed tomography angiography (HCTA) accurately depicts arterial diseases, including the location and extent of arterial calcification. The objective of this study was to assess the value of HCTA with maximum-intensity-projection (MIP) reconstruction to evaluate iliac arterial calcifications and stenosis among candidates for renal transplantation. MATERIAL AND METHODS: From December 1997 to March 2002, 114 HCTA scans with MIP reconstruction were performed in candidates for renal transplantation. Included patients fulfilled some of the following conditions: (a) older than 55 years, (b) diabetic, (c) second transplants, and (d) obvious vascular calcifications on plain abdominal x-ray. RESULTS: Among the 114 patients, 33 (29%) were excluded for transplantation due to universal calcification of the iliac arterial sector, and 81 (71%) were included on the waiting list due to the presence of calcium-free areas for the vascular anastomosis. Transplantation, which was attempted in 28 of the 81 patients, was successful in 25 using the area programmed after HCTA analysis. The transplants failed in three cases because no calcium-free area could be found upon surgical examination. CONCLUSION: HCTA with MIP reconstruction makes it possible to draw an exact map of the arterial calcifications of the iliac arterial sector, allowing better recipient selection and accurate planning for the vascular anastomosis and placement of the renal graft.     

Portal venous reconstruction in a living liver donor with an anomalous hepatic arterial and portal venous anatomy

Hepatic arterial and portal venous anomalies in living liver donors are not uncommon. Modified surgical techniques may be required in such circumstances, although the safety of the living donor must always be given top priority. We describe here a successful portal venous reconstruction in a living donor with an anomalous hepatic arterial and portal venous anatomy in which the right anterior and posterior hepatic arteries encircled the main portal vein. Although such an anomaly of hepatic vessels was not frequently encountered, we should be able to alter the surgical strategy to deal with it. This case illustrates the importance of preoperative hepatic artery and portal venous evaluation in all living donors to identify the feasibility of modifying vessel anastomoses in living donors, as well as recipients, before living donor liver transplantation.     

Improvements in hepatic parenchymal transection for living related liver donor

INTRODUCTION: To eliminate mortality and morbidity risk in living related liver donors, we developed a new surgical technique to resect hepatic parenchyma using an ultrasonic surgical aspirator in association with a monopolar floating ball cautery. METHODS: We performed 17 right hepatectomies and 2 left hepatectomies using this technique. We performed a retrospective analysis of perioperative mortality, length of hospitalization (LOS), blood transfused during surgery (IBT), intraoperative blood lost (IBL), biliary complications (BC), and aspartate aminotransferase (AST)/alanine aminotransferase (ALT) peak in the first postoperative week. This group of patients (Group A) was compared, using the analysis of variance (ANOVA) test (P < .05) with 2 different groups of 19 patients: Group B with liver neoplasms that had the same technique as Group A, and Group C wherein a crushing clamp technique was used. RESULTS: All of the analyzed variables showed significative statistical differences, especially between Group A and Group C (IBL, P < .000; IBT, P < .006; LOS, P < .028; BC, P < .000; AST peak, P < .041; and ALT peak, P < .023). DISCUSSION: The association of these 2 techniques seems to reduce the LOS, and the need for intraoperative blood transfusions. Moreover, the surgical complications (biliary leaks) and the postoperative parenchymal cytonecrosis seem to be less using this technique.     

Preoperative assessment of perigastric vascular anatomy by multidetector computed tomography angiogram for laparoscopy-assisted gastrectomy

Purpose

We aimed at investigating the efficacy of multidetector computed tomography (MDCT) angiogram reconstructed using the maximum intensity projection (MIP) technique for the assessment of perigastric vascular anatomy before laparoscopy-assisted gastrectomy (LAG) for gastric cancer.

Methods

Seventy-one patients who underwent LAG were enrolled in the study. Contrast-enhanced scans of the portal venous phase were performed by a MDCT scanner. The CT images were reconstructed using thin-slab MIP. The anatomic variations in the inflow and the location of the left gastric vein (LGV) were detected. The patterns of perigastric arterial origins were divided according to Michels' classification. The intraoperative blood loss on LAG was compared before and after MDCT angiography was introduced in the study.

Results

The LGV flowed into the portal vein in 31 patients; the splenic vein, 25 patients; and the junction of these two veins, 15 patients. The LGV passed to the dorsal and ventral sides of the common hepatic artery in 30 and 13 patients and to the dorsal and ventral sides of the splenic artery in 8 and 20 patients, respectively. Michels' type II was found in one patient; type V, in three patients; and type VI, in two patients. The LGV location detected by MDCT was confirmed during surgery in all cases. Intraoperative blood loss after introduction of the MDCT angiography was significantly less than that before its introduction (p?=?0.0032).

Conclusions

An MDCT angiogram reconstructed using the MIP technique is effective for assessing the perigastric vascular anatomy before LAG for gastric cancer.     

Accuracy of multidetector computed tomographic angiography for detecting hepatic artery complications after liver transplantation

Aims

The aim of this study was to evaluate the accuracy of multidetector computed tomographic angiography (MDCTA) for detecting hepatic artery complications after liver transplantation.

Methods

Between July 2001 and September 2006, 212 patients underwent liver transplantation including 110 (41 female and 69 male patients); of mean age, 24 years (range = 6 months to 66 years) who were assessed with MDCTA. First, arterial phase images obtained after intravenous injection of 150 mL of contrast at a rate of 4 mL/s were acquired using the bolus triggering technique. Then portal and late-phase images were obtained. Axial and coronal maximum intensity projection (MIP) images and volume-rendered images were produced from the axial image data. Arterial vascular complications were noted. Stenosis was defined as severe (>75%), moderate (≥50%), or mild (<50%) according to its diameter. Twenty-nine of the 38 individuals with hepatic artery complications detected by MDCTA had correlative digital subtraction angiography (DSA). Seven of 110 patients with normal hepatic artery and venous pathologies in MDCTA also had DSA to investigate venous complications.

Results

MDCTA showed hepatic artery complications in 38 of the 110 patients who were assessed with this modality. DSA confirmed the MDCTA findings in all but 1 of the 29 patients assessed with catheter angiography. Fourteen of the 38 individuals also underwent percutaneous interventions and treatment. Fifteen patients had early hepatic artery complications, and 23 late hepatic artery complications. The most common early complications were thrombosis (66.6%) and stenosis (26.6%). The most common late complications were stenosis (56.5%) and thrombosis (26%). If we evaluate the early and late complications, the incidence of late complications was greater than that of the early complications (61% vs 39%). There was no statistically significant difference in cadaveric and living donor liver transplants for early versus late or for type of complications.

Conclusions

MDCTA is noninvasive imaging modality that accurately shows a variety of vascular complications after liver transplantation. We suggest that if we suspect any vascular complication with Doppler ultrasound, we must perform MDCTA for diagnosis. If we detect severe/moderate stenosis, the patient must undergo DSA.     

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目的：分析10例活体肝移植术中的血管变异，总结其外科处理经验，进一步提高手术成功率，减少并发症。方法：2001年1月至12月，行活体肝移植10例，其中左半肝8例，左外叶1例，右半肝1例，供肝者均为其母，经术中B超及胆管造影以确定肝切线。供体单支肝动脉分支与受体肝动脉吻合，两支肝动脉分别与受体肝左、右动脉吻合。门静脉分支与受体门静脉主干吻合。供体肝静脉与受体下腔静脉行端侧吻合。胆管重建均采用肝管分支与受体胆总管端端吻合，置T管引流。结果：10例活体肝移植，1例因肝动脉血栓形成，术后5天需次肝移植；1例发生排斥；其余8例均康复出院，5例已上学。结论：活体肝移植术中血管重建技术是其重要环节，术前和术中了解供受体解剖变异并正确处理，可减少术后血管和胆道的并发症。     

64层CT诊断冠状动脉狭窄的准确性:与常规血管造影比较

目的评价64层螺旋CT冠状动脉造影对冠状动脉明显狭窄诊断准确性和可行性。方法218例冠心病疑似患者在一周内进行了64层CT冠状动脉造影及常规血管造影,对冠状动脉的主干及主要分支进行诊断,以冠状动脉造影结果为金标准评价64层CT诊断冠状动脉狭窄的准确性。结果多层螺旋CT所显示的2592支冠状动脉中冠状动脉狭窄173处,正确诊断166处,漏诊7处,误诊28处,敏感性95.9%,特异性98.6%,阳性预测值90.2%,阴性预测值99.7%,准确率98.4%。结论64层螺旋CT对冠状动脉狭窄诊断有较高的准确性,可作为高危人群普查筛选的首选方法之一。     

Sixteen-row multislice computed tomography angiography in the diagnosis and characterization of intracranial aneurysms: comparison with conventional angiography and intraoperative findings

OBJECT: The goal of this study was to prospectively compare the effectiveness of 16-slice computed tomography (CT) angiography with that of conventional digital subtraction (DS) angiography and the surgical findings used to detect and characterize intracranial aneurysms. METHODS: Two hundred forty-four consecutive patients underwent both CT angiography and DS angiography no more than 3 days apart. Computed tomography angiography was performed with a 16-row multislice CT scanner in which a collimation of 0.75 mm was used. Two observers independently reviewed the CT images, and 1 of the 3 attending neuroradiologists reviewed the DS angiograms. They determined the presence, location, quantitation, and characterization of the intracranial aneurysms. Statistical results were calculated independently for the image interpretation performed by the 2 CT scan readers and the DS angiogram reader by using the combination of DS angiography or intraoperative findings or both as a reference standard. RESULTS: One hundred thirty-six patients harboring 153 intracranial aneurysms were included in this series. There was no statistically significant difference in sensitivity between 16-slice CT angiography and conventional DS angiography (p > 0.05). The sensitivities of 16-slice CT angiography for aneurysms < 5 mm, 5-10 mm, and > 10 mm were 94.8, 100, and 100%, respectively, on a per-aneurysm basis. The overall sensitivity and specificity of CT angiography for aneurysms were 98.0 and 99.1%, respectively. Sixteen-slice CT angiograms were clearer and more accurate in depicting the relationship of aneurysms to bone structures and adjacent branch vessels. CONCLUSIONS: Computed tomography angiography using a 16-slice scanner is an accurate tool for detecting and characterizing intracranial aneurysms, including small aneurysms. Noninvasive 16-slice CT angiography will become a viable replacement for conventional DS angiography in the diagnosis and characterization of aneurysms.     

Safety of multidetector computed tomography in calculating liver volume for living-donor liver transplantation

Living-related liver transplantation was developed to overcome the organ shortage for both children and adults with end-stage liver disease. Because impaired liver function after resection and transplantation is caused by insufficient liver volume, the reliable volumetric assessment of the hepatic segments of potential living donors is a critical element in preoperative evaluation. In this study, we compared the results of multidetector computed tomographic (CT) volumetry with the intraoperative findings from 80 liver transplantations performed at our center. Resection borders were determined preoperatively with the aid of CT by manual delineation in which the hepatic vessels were used as guides. Resected liver grafts were weighed intraoperatively, and the calculation of their volume was based on the specific weight of 1 g/mL. Statistical analyses were performed with Pearson's correlation test; P < .05 was considered significant. The study subjects consisted of 48 women and 32 men (mean age, 35.6 +/- 9.7 years; range, 23-56 years). Forty-one donors underwent right lobectomy, 22 underwent left lobectomy, and 17 underwent left lateral segmentectomy. Manual volumetric measurement was completed within 15 minutes. No significant differences were found between the results of preoperative volumetry and the intraoperative measurement. We therefore concluded that manual CT volumetric calculation is a reliable method of calculating liver volume for living-donor liver transplantation.     

右叶活体肝移植的肝静脉应用解剖研究

目的 研究右叶活体肝移植的肝静脉应用解剖.方法 解剖观测133例成人肝静脉的分支数、最大径、长度、肝外长度、汇合;肝中静脉相对于肝中裂的偏移程度等指标.结果 A型:粗大的肝右静脉和小的右副肝静脉,占59.4%,B型:中等大小的肝右静脉和中等大小的右副肝静脉,占27.8%,C型:小的肝右静脉和粗大的右副肝静脉,占12.8%.肝左静脉与肝右肝静脉共干,占60.3%,共干长度(1.12±0.61)cm,大小(1.29±0.40)cm.96.15%肝中静脉相对于肝中裂的向右偏移,偏移程度(14.11±12.65)°.结论 该组肝静脉的结果 提示中国人的肝静脉分型中各型所占的比例与国外文献报道明显不同;中国人可能更适合右叶活体肝移植.     

Preoperative evaluation of biliary anatomy of donor in living donor liver transplantation by conventional nonenhanced magnetic resonance cholangiography

Detailed preoperative evaluation of the biliary anatomy of the donor in living donor liver transplantation (LDLT) can minimize postoperative morbidity in the recipient and maximize safety for the donor. We prospectively evaluated the diagnostic accuracy and clinical usefulness of nonenhanced conventional magnetic resonance cholangiography (MRC) for depicting the biliary anatomy of LDLT donors. MRC and intraoperative cholangiography (IOC) examinations of 111 donors were performed between August 2005 and February 2006. We observed the classical branching pattern of the biliary system in 67 subjects (60.4%), with the remaining 44 subjects (39.6%) showing anatomical variations. MRC showed accurate anatomy of the biliary system, using IOC as the reference standard, in 98 (88.3%) subjects. MRC had a sensitivity in differentiating normal from variant anatomy of 95.5%, specificity of 95.2%, a positive predictive value of 96.8% and a negative predictive value of 93.3%. The agreement between MRC and IOC findings, as evaluated by kappa-value (0.865) was statistically significant (P<0.001). In conclusion, the diagnostic accuracy of conventional nonenhanced MRC is sufficient for this method to be used for the preoperative evaluation of biliary anatomy in LDLT donor candidates.     

"All-in-one" imaging protocols for the evaluation of potential living liver donors: comparison of magnetic resonance imaging and multidetector computed tomography.

In order to compare the performance of "all-in-one" magnetic resonance imaging (MRI) and "all-in-one" multidetector computed tomography (MDCT) in the preharvest evaluation 25 potential living donors underwent both MRI and MDCT. MRI was performed on a high-performance 1.5-T scanner, computed tomography (CT) on a 4-row multidetector-scanner. Both scan protocols included angiography of the arterial and venous hepatic systems. CT additionally included infusion of a biliary contrast agent. Data analysis was performed by 4 reviewers, based on source images, multiplanar reformats, and three-dimensional (3D) postprocessing. Determination of image quality was based on a 4-point image quality rating (IQR) scale, ranging from 1 = nondiagnostic to 4 = excellent. Preoperative and intraoperative (n = 13) findings were correlated. Magnetic resonance (MR) examinations were generally well tolerated. Within the CT scan, 2 candidates presented moderate adverse reaction to the biliary contrast agent. MRI and CT showed the same benign parenchymal lesions (IQR MR: 3.7; IQR CT: 3.4). Determination of liver volumes was easier based on CT (IQR MR: 3.3; IQR CT: 3.6). Magnetic resonance angiography (MRA) revealed 10 variants of the arterial liver supply (IQR: 3.0) and computed tomographic angiography (CTA) revealed 13 variants (IQR: 3.5). Magnetic resonance cholangiopancreatography (MRCP) identified 4 biliary variants (IQR: 1.3) and CT cholangiography identified 17 (IQR: 3.5). MRI and CT each showed 4 hepatic and portal venous variants (IQR MR: 3.4, CT: 2.8). CT and MR findings correlated well with intraoperative findings. In conclusion, both techniques proved to be efficient to evaluate potential living liver donors' anatomy in a single diagnostic step. The main advantage of CT lies in the ability to accurately assess the biliary anatomy.