Pancreatic arterial anatomy: depiction with dual-phase helical CT

MDCT evaluation of Dorsal Pancreatic Artery and Intrapancreatic arcade anatomy

OBJECTIVE

The purpose of the study was to analyze the anatomy and variations in the origin of the dorsal pancreatic artery, greater pancreatic artery and to study the various types of arterial arcades supplying the pancreas on multidetector CT (MDCT).

METHODS

A retrospective analysis of 747 MDCT scans was performed in patients who underwent triple phase or dual phase CT abdomen between December 2020 and October 2022. Variations in origin of Dorsal pancreatic artery (DPA), greater pancreatic artery (GPA), uncinate process branch were studied. Intrapancreatic arcade anatomy was classified according to Roman Ramos et al. into 4 types-small arcades (type I), small and large arcades (type II), large arcades (type III) and straight branches (type IV).

RESULTS

The DPA was visualized in 65.3% (n = 488) of cases. The most common origin was from the splenic artery in 58.2% (n = 284) cases. The mean calibre of DPA was 2.05 mm (1.0-4.8 mm). The uncinate branch was seen in 21.7% (n = 106) with an average diameter of 1.3 mm. The greater pancreatic artery was seen in 57.3% (n = 428) predominantly seen arising from the splenic artery. The most common arcade anatomy was of Type II in 52.1% (n = 63) cases.

CONCLUSION

Pancreatic arterial variations are not very uncommon in daily practice. Knowledge of these variations before pancreatic surgery and endovascular intervention procedure is important for surgeons and interventional radiologist.

Anatomical basis for pancreas transplantation via isolated splenic artery perfusion: A literature review

The variability of vascular anatomy of the pancreas underlines the difficulty of its transplantation. Research regarding the consistency of anatomical variations shows splenic arterial dominance in most cases. This can significantly improve transplantation success. A systematic literature review was performed according to the quality standards described in the AMSTAR measurement tool and the PRISMA guidelines. We valuated existing literature regarding the vascularization and blood perfusion patterns of the pancreas in terms of dominance and variability. The collected data was independently analyzed by two researchers. Variance of vascular anatomy was seen to be underreported in literature, though significant findings have been included and discussed in this study, providing valuable insight into the dynamics of pancreatic perfusion and feasibility of transplantation on several different supplying arteries. The splenic artery (SA) has a high percentage of consistency in all found studies (over 90%). High frequency of anastomoses between arterial pools supplying the pancreas can mediate sufficient blood supply through a dominant vessel, such as the SA, which is present in most cases. Pancreatic transplantation with isolated SA blood supply can provide sufficient arterial perfusion of the pancreas for stable transplant viability due to high anatomical consistency of the SA and vast communications with other arterial systems.

The dorsal pancreatic artery: A meta-analysis with clinical correlations

BACKGROUND/OBJECTIVES

The dorsal pancreatic artery is the main artery of the body and tail of the pancreas. Its origin and branching is highly variable. The aim of this study was to perform a meta-analysis to generate pooled prevalence data on the presence and origin of the dorsal pancreatic artery. Clinically important aspects of the dorsal pancreatic artery were summarised during the literature review.

METHODS

Major medical databases were searched. Data on the presence and point of origin of the dorsal pancreatic artery were extracted and quantitatively synthesised. The obtained data of anatomical based studies and computed tomography based studies were statistically analysed.

RESULTS

In total, 30 studies, comprising 2322 anatomical and computed tomography based cases were included. The dorsal pancreatic artery was present in 95.8% of cases. It originated from the splenic artery in 37.6% of cases, common hepatic artery in 18.3% of cases, coeliac trunk in 11.9% of cases and the superior mesenteric artery in 23.9% of cases. Other rare origins were present in 2.77% of cases. Multiple dorsal pancreatic arteries were found in 1,7% of cases. There was no significant difference in the presence or origin of the dorsal pancreatic artery between anatomical and computed tomography based studies.

CONCLUSION

The dorsal pancreatic artery is present in the vast majority of cases. Its origin and branching are highly variable. Multiplicity of the dorsal pancreatic artery is infrequent.

Anatomy of peripancreatic arteries and pancreaticoduodenal arterial arcades in the human pancreas: a cadaveric study

INTRODUCTION

The purpose of this work was to evaluate the arteries supplying the pancreaticoduodenal (PD) complex.

MATERIALS AND METHODS

The study was conducted on 15 fresh enbloc pancreatic specimens by latex injection method which enabled the visualization of the peripancreatic arteries and their minute branches.

RESULTS

The gastroduodenal (GDA), anterior superior pancreaticoduodenal (ASPD), and anterior inferior pancreaticoduodenal (AIPD) artery was found in all the cases, whereas the posterior superior pancreaticoduodenal (PSPD) and posterior inferior pancreaticoduodenal (PIPD) artery was present in 93.34% cases. The ASPD artery originated from GDA in all the cases. Two types of variations were observed in the origin of PSPD artery and four types each in the origin of AIPD and PIPD artery. Anatomical and numerical variations were observed in both anterior and posterior arches, posterior arch being absent in 20% cases.

CONCLUSIONS

In the present study, an attempt was made to systematically describe the individual arterial configurations of the PD complex. The information provided here has important implications for preoperative planning of technically challenging surgeries and interventions around the pancreatic head.

The Arterial Supply of the Distal Part of the Pancreas

The pancreatic surgery field has evolved greatly over the previous years. Nevertheless, the vascularization of the pancreas remains a difficult subject and requires further attention. The study was conducted using macroscopical dissection and corrosion cast methods. The total number of organ blocks was 72 (50 for dissection and 22 for corrosion cast). Based on the data obtained by dissection, we can distinguish three major types of vascularization of the distal pancreas. In type one, the pancreas was vascularized only by the short branches of the splenic artery and was encountered in 18 cases (36%). In type two, the pancreas was vascularized by the long and short branches of the splenic artery and was encountered in 20 cases (40%). In type three, the pancreas was vascularized only by the long branches of the splenic artery in 12 cases (24%). Compared to that, the corrosion cast method demonstrated type 1 in 8 cases (36.36%), type 2 in 10 cases (45.46%), and type 3 in 4 cases (18.18%). During the dissection, there were no arteries to the tail of the pancreas in 13 (26%) cases, one artery in 15 (30%) cases, two arteries in 19 (38%), and three arteries in three (6%) cases. The 22 corrosion cast specimens were also evaluated based on the classification of Roman Ramos and coworkers. Type I (small arcades) was in 9 (40.90%) cases, type II (small and large arcades) was in 7 (31.82%) cases, type III (large arcades) was in 5 (22.73%) cases, and type IV (straight branches) was in 1 (4.55%) case. The corrosion cast method allowed us to determine no arteries to the tail in 4 (18.18%) cases, one artery in 6 (27.27%) cases, two arteries in 10 (45.46%) cases and three arteries in two (9.09%) cases. The vascularization of the distal part of the pancreas is highly variable and should be taken into consideration during surgery.

Anatomo-radiological patterns of pancreatic vascularization, with surgical implications: Clinical and anatomical study

The pancreas receives multiple arterial sources that should be considered in patients undergoing pancreatic surgery. The aim of this study is to describe pancreatic vascularization and to explore the anatomical basis of postoperative complications. Ten specimens from unembalmed cadavers, including the retroperitoneal vessels and organs and spleen, were injected with acrylic resins to obtain vascular casts. Thirty computed tomography angiographies (CTA) of subjects with no pancreatic pathology (mean age 70.9 years) were also analyzed. A paucivascular area at the neck of the pancreas was apparent in all vascular casts. At CTA: (1) the transverse pancreatic artery, the only artery running from the cervicocephalic to the somatocaudal segment, was visible in 76.9% of cases; (2) the splenic artery was suprapancreatic in 66.7% and intrapancreatic with a tortuous course in 33.3%; (3) the posterior superior pancreaticoduodenal artery was visible in 100% of cases, the anterior superior pancreatico-duodenal artery in 92.6%, the anterior inferior pancreaticoduodenal artery in 73.1%, the posterior inferior pancreaticoduodenal artery in 86.4%, the dorsal pancreatic artery in 65.4%, the great pancreatic artery in 73.1%, and the pancreatic arteries to the body and caudal pancreatic arteries in 96.2%. Our study demonstrated great individual variability of the pancreatic vasculature, which can be explored by CTA and could be relevant to surgical procedures. Clin. Anat. 30:614-624, 2017. © 2017 Wiley Periodicals, Inc.

Clinical evaluation, imaging studies, indications for cytologic study and preprocedural requirements for duct brushing studies and pancreatic fine-needle aspiration: The Papanicolaou Society of Cytopathology Guidelines

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pancreaticobiliary cytology including indications for endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) biopsy, techniques for EUS-FNA, terminology and nomenclature to be used for pancreaticobiliary disease, ancillary testing and postbiopsy management. All documents are based on expertise of the authors, literature review, discussions of the draft document at national and international meetings and synthesis of online comments of the draft document. This document selectively presents the results of these discussions. This document summarizes recommendations for the clinical and imaging work-up of pancreatic and biliary tract lesions along with indications for cytologic study of these lesions. Prebrushing and FNA requirements are also discussed.

Clinical evaluation, imaging studies, indications for cytologic study, and preprocedural requirements for duct brushing studies and pancreatic FNA: the Papanicolaou Society of Cytopathology recommendations for pancreatic and biliary cytology

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pancreaticobiliary cytology including indications for endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) biopsy, techniques for EUS-FNA, terminology and nomenclature to be used for pancreaticobiliary disease, ancillary testing, and post-biopsy management. All documents are based on expertise of the authors, literature review, discussions of the draft document at national and international meetings, and synthesis of online comments of the draft document. This document selectively presents the results of these discussions. This document summarizes recommendations for the clinical and imaging work-up of pancreatic and biliary tract lesions along with indications for cytologic study of these lesions. Prebrushing and FNA requirements are also discussed.

Three-dimensional volume-rendered multidetector CT imaging of the posterior inferior pancreaticoduodenal artery: its anatomy and role in diagnosing extrapancreatic perineural invasion

Extrapancreatic perineural spread in pancreatic adenocarcinoma contributes to poor outcomes, as it is known to be a major contributor to positive surgical margins and disease recurrence. However, current staging classifications have not yet taken extrapancreatic perineural spread into account. Four pathways of extrapancreatic perineural spread have been described that conveniently follow small defined arterial pathways. Small field of view three-dimensional (3D) volume-rendered multidetector computed tomography (MDCT) images allow visualization of small peripancreatic vessels and thus perineural invasion that may be associated with them. One such vessel, the posterior inferior pancreaticoduodenal artery (PIPDA), serves as a surrogate for extrapancreatic perineural spread by pancreatic adenocarcinoma arising in the uncinate process. This pictorial review presents the normal and variant anatomy of the PIPDA with 3D volume-rendered MDCT imaging, and emphasizes its role as a vascular landmark for the diagnosis of extrapancreatic perineural invasion from uncinate adenocarcinomas. Familiarity with the anatomy of PIPDA will allow accurate detection of extrapancreatic perineural spread by pancreatic adenocarcinoma involving the uncinate process, and may potentially have important staging implications as neoadjuvant therapy improves.

Arterial anatomy of the pancreas. Part 3: segmented computed tomography-angiography mapping of perineural invasion

This is the third in a series of medical graphics articles featuring the arterial anatomy of the pancreas as depicted on segmented computed tomography-angiography. These segmented computed tomography-angiography displays serve as a road map of the routes of tumor spread by ductal adenocarcinoma of the pancreas because perineural tumor invasion parallels the pancreatic arteries.

Arterial supply to the pancreas; variations and cross-sectional anatomy

The pancreas has complex arterial supplies. Therefore, special attention should be paid in pancreatic arterial intervention for patients with acute pancreatitis and pancreatic carcinomas. Knowledge of pancreatic arterial anatomy and arterial territory is important not only to perform pancreatic arterial intervention, but to read the pancreatic angiography and cross-sectional image. We reviewed 226 selective abdominal angiography and CT scans during selective arteriography (CTA) of common hepatic artery, superior mesenteric artery, splenic artery, or peripancreatic arteries including posterior superior pancreaticoduodenal artery, anterior superior pancreaticoduodenal artery, inferior pancreaticoduodenal artery, and dorsal pancreatic artery. CTA images were evaluated to clarify the cross-sectional anatomy of the pancreatic arterial territory. Variations of the peripancreatic arteries were also investigated. In this exhibit, schemes and illustrative cases demonstrate pancreatic arterial territory and variations.

Vascular invasion in pancreatic cancer: Imaging modalities, preoperative diagnosis and surgical management

Pancreatic cancer is associated with a poor prognosis, and surgical resection remains the only chance for curative therapy. In the absence of metastatic disease, which would preclude resection, assessment of vascular invasion is an important parameter for determining resectability of pancreatic cancer. A frequent error is to misdiagnose an involved major vessel. Obviously, surgical exploration with pathological examination remains the “gold standard” in terms of evaluation of resectability, especially from the point of view of vascular involvement. However, current imaging modalities have improved and allow detection of vascular invasion with more accuracy. A venous resection in pancreatic cancer is a feasible technique and relatively reliable. Nevertheless, a survival benefit is not achieved by curative resection in patients with pancreatic cancer and vascular invasion. Although the discovery of an arterial invasion during the operation might require an aggressive management, discovery before the operation should be considered as a contraindication. Detection of vascular invasion remains one of the most important challenges in pancreatic surgery. The aim of this article is to provide a complete review of the different imaging modalities in the detection of vascular invasion in pancreatic cancer.

Three-dimensional models of arteries constructed using multidetector-row CT images to perform pancreatoduodenectomy safely following dissection of the inferior pancreaticoduodenal artery

BACKGROUND/PURPOSE

During a pancreatoduodenectomy (PD) it is important that the anatomy of the arcade of blood vessels in the head of the pancreas is fully understood before the surgery in order to reduce intraoperative bleeding. In most of the patients our group has treated, the inferior pancreaticoduodenal artery (IPDA), one of the efferent arteries of the head of the pancreas, has formed a short common trunk with the first jejunal artery (FJA). Thus, by first locating the origin of the FJA, it was easier to locate the IPDA. There are two ways to locate the IPDA: (1) by measuring the distance between the origin of the superior mesenteric artery (SMA) and that of the FJA; (2) by measuring the distance between the origin of the middle colic artery (MCA) and that of the FJA. Here, we report our measurements of both distances using three-dimensional (3D) models of arteries constructed with multidetector-row computed tomography (MD-CT) images and discuss which is the better measurement to determine the location of the IPDA during PD.

METHODS

A total of 140 patients underwent 64-MD-CT imaging to acquire early and late arterial phase scans. The distance between the origin of the SMA and that of the FJA and the distance between the origin of the MCA and that of the FJA origin were measured.

RESULTS

In patients whose IPDA formed either a common trunk with the FJA or arose directly from the SMA, the IPDA or the common truck was located in parallel with the SMA at a very short distance of approximately 18 mm from the MCA origin towards the center. The distance between the SMA origin and the IPDA was significantly longer (approximately 36 mm). Therefore, locating the MCA origin during PD helped determine the location of the IPDA. However, in patients whose anterior inferior pancreaticoduodenal artery (AIPDA) and posterior inferior pancreaticoduodenal artery (PIPDA) arose separately, the distance between the AIPDA origin and the MCA origin was approximately 18 mm, the distance between the AIPDA origin and the PIPDA origin was approximately 19 mm, and the distance between the PIPDA origin and the SMA origin was 19 mm. Thus, locating the SMA helped determine the location of the IPDA during PD in these patients.

CONCLUSION

Based on our findings that the distance between the IPDA origin and the MCA origin was short, we have shown that it is effective to locate the MCA origin in order to determine the location of the IPDA.

[Pancreas. Congenital changes, acute and chronic pancreatitis]

The pancreas develops from ventral and dorsal buds, which undergo fusion. Failure to fuse results in pancreas divisum, which is defined by separate pancreatic ductal systems draining into the duodenum. Risk of developing pancreatitis is increased in pancreas divisum. MR cholangiopancreatography (MRCP) is the technique of choice for detecting it non-invasively. Annular pancreas is the result of incomplete rotation of the pancreatic bud around the duodenum with the persistence of parenchyma or a fibrous band encircling (stenosing) the duodenum. Acute pancreatitis is usually caused by bile duct stones or alcohol abuse. Contrast-enhanced multi-detector row CT is the method of choice to assess the extent of this disease. In acute pancreatitis, the role of MRCP is mainly limited to finding bile duct stones in patients with suspected biliary pancreatitis. Chronic pancreatitis results in relentless and irreversible loss of exocrine (and sometimes endocrine) function of the pancreas. MDCT even shows subtle calcifications. MRCP is the method of choice for non-invasive assessment of the duct. Inflammatory pseudotumor in chronic pancreatitis and groove pancreatitis are difficult to differentiate from pancreatic cancer. In these cases, multiple imaging methods such as MDCT, MRI and endosonography including biopsy may be used to make a diagnosis.

Portal venous system: evaluation with unenhanced MR angiography with a single-breath-hold ECG-synchronized 3D half-Fourier fast spin-echo sequence

OBJECTIVE

Eighteen healthy persons underwent unenhanced MR angiography with a breath-hold ECG-synchronized 3D half-Fourier fast spin-echo technique to evaluate the visibility of the portal vein and its branches.

CONCLUSION

Our results indicated that unenhanced MR angiography with a singlebreath-hold ECG-synchronized 3D half-Fourier fast spin-echo sequence facilitates precise visualization of the anatomic features of the portal vein and its branches without the use of contrast agents.

Guidelines for the Surgical Management of Pancreatic Adenocarcinoma

Pancreaticoduodenectomy remains the most formidable operative procedure for the surgical treatment of gastrointestinal malignancy. Improved outcomes after the Whipple procedure have been attributed to better preoperative patient selection, advances in three-dimensional radiographic imaging, and regionalization of referrals to high-volume, tertiary care centers. Despite these advances, morbidity and mortality after pancreaticoduodenectomy are not insignificant and the overall prognosis following resection for adenocarcinoma of the pancreas remains poor. Improvements in endoscopic decompression of malignant biliary obstruction have decreased the need for palliative bypass operations and have focused current surgical issues on ways to improve clinical outcomes following potentially curative resections. Controversies such as whether or not to perform extended lymph node dissections, and standard versus pylorus-preserving resections have been addressed by randomized, prospective clinical trials. Major venous resections secondary to local tumor extension are now performed without an increase in morbidity or mortality and with survival rates comparable to standard resections. This has led to even more aggressive resections following neoadjuvant therapy for lesions previously considered unresectable and now perhaps better categorized as borderline resectable. The impact of surgical specialization and regionalization of referrals to tertiary care centers is evident in markedly improved perioperative mortality rates. This article will attempt to describe current guidelines for the preoperative, intraoperative, and postoperative management of patients with localized pancreatic adenocarcinoma.

[Pancreas. Part I: congenital changes, acute and chronic pancreatitis]

The pancreas develops from ventral and the dorsal buds, which undergo fusion. Failure to fuse results in pancreas divisum, which is defined by separate pancreatic ductal systems draining into the duodenum. Risk of developing pancreatitis is increased in pancreas divisum because of insufficient drainage. MR cholangiopancreatography (MRCP) is the technique of choice for detecting pancreas divisum non-invasively. Annular pancreas is the result of incomplete rotation of the pancreatic bud around the duodenum with the persistence of parenchyma or a fibrous band encircling (and sometimes stenosing) the duodenum. Acute pancreatitis is usually caused by bile duct stones or alcohol abuse. The Atlanta classification differentiates between mild acute and severe acute pancreatitis associated with organ failure and/or local complications such as necrosis, abscess or pseudocyst. Contrast-enhanced multi-detector row CT is the method of choice to assess the extent of disease. Balthazar et al.'s CT severity index assesses the risk of mortality and morbidity. In acute pancreatitis, the role of MRCP is mainly limited to finding bile duct stones in patients with suspected biliary pancreatitis. Chronic pancreatitis results in relentless and irreversible loss of exocrine (and sometimes endocrine) function of the pancreas. MDCT even shows subtle calcifications. MRCP is the method of choice for non-invasive assessment of the duct. Inflammatory pseudotumor in chronic pancreatitis and groove pancreatitis are difficult to differentiate from pancreatic cancer. In these cases, multiple imaging methods such as MDCT, MRI and endosonography including biopsy may be used to make a diagnosis.

Systematic review of carbohydrate antigen (CA 19-9) as a biochemical marker in the diagnosis of pancreatic cancer

BACKGROUND

Although many biochemical markers have been examined in pancreatic cancer none are definitive for pre-operative diagnosis. This systematic review examines studies using biochemical markers for the diagnosis of pancreatic cancer in order to appraise their role in contemporary management algorithms.

METHODS

A search of the MEDLINE database was undertaken using the key words pancreatic neoplasm and serum tumour marker. Only studies providing original data on sensitivity and specificity are included and data are presented on diagnostic accuracy, effect of cholestasis and the relation of tumour stage to blood levels of markers.

RESULTS

CA 19-9 is the most extensively evaluated with pooled data from 2283 patients. The median sensitivity of CA 19-9 for diagnosis is 79 (70-90%) and median specificity 82 (68-91%). CA 19-9 elevation in non-malignant jaundice results in a fall in specificity. Combination with other markers improves accuracy.

CONCLUSION

As the most extensively evaluated marker, CA 19-9 should be used in contemporary algorithms for the diagnosis of pancreatic cancer. Elevated values should be repeated after relief of jaundice.

CT depiction of small arteries in the pancreatic head: assessment using coronal reformatted images with 16-channel multislice CT

BACKGROUND

To assess the capabilities of 16-channel multislice CT in acquiring almost exclusively arterial-phase images of the pancreas and depicting small pancreatic arteries in coronal reformatted images.

MATERIALS AND METHODS

In 45 consecutive patients, arterial-phase contrast enhancement was measured in the aorta and its branches, portal venous system, and pancreas. Coronal reformatted images of 1.2- or 1.3-mm slice thickness at 0.8- or 0.9-mm intervals were generated from axial images acquired with 0.5-mm collimation. Two radiologists evaluated the quality of imaging in the arterial phase and the visibility of the pancreatic arteries in coronal reformatted images.

RESULTS

Mean enhancement in the aorta and its branches was greater than 300 HU, while that in the portal venous system and pancreas was less than 100 HU. The images were judged to be suitable for delineating the pancreatic arteries in all patients. The following arteries were visualized: anterior superior pancreaticoduodenal (39 patients), posterior superior pancreaticoduodenal (41), anterior inferior pancreaticoduodenal (39), posterior inferior pancreaticoduodenal (33), dorsal pancreatic (42), its right branch (34), and transverse pancreatic (37).

CONCLUSION

Multislice CT can depict small pancreatic arteries using coronal reformatted images generated from almost exclusively arterial-phase axial images acquired with 0.5-mm collimation.

HELICAL COMPUTED TOMOGRAPHIC ANGIOGRAPHY OF THE NORMAL CANINE PANCREAS

Helical abdominal computed tomography (CT) was performed in nine normal beagle-mix dogs. Following cephalic vein injection of ionic iodinated contrast medium via power injector (rate 5 ml/s) dual-phase CT was performed in all dogs. A delayed scan was performed in five dogs between 5 and 13 min after the contrast medium injection. The median time of appearance of contrast medium in the aorta and gastroduodenal artery was 6.3 and 7 s, post start injection and 12 and 12.2 s in the gastroduodenal and portal vein, resulting in a purely arterial pancreatic time window of 5-6s. Pancreatic veins and parenchyma remained enhanced until the end of the dynamic scan (40s). The pancreatic parenchyma showed heterogeneous arterial and homogenous venous contrast enhancement which was slightly hypoattenuating compared to the liver. Delayed scans provided best delineation of the pancreas from the liver. The common bile duct could be identified ventral and to the right of the portal vein joining the dorsomedial aspect of proximal duodenum. Because of the very short time window and variable onset of pure arterial enhancement careful planning of dual-phase studies with previous dynamic CT is recommended. Dual-phase CT angiography enables assessment of the arterial supply, parenchymal perfusion and venous drainage of the canine pancreas.

Efficacy of multislice computed tomography for gastroenteric and hepatic surgeries

AIM: To determine the efficacy of multislice CT for gastroenteric and hepatic surgery.

METHODS: Dual-phase helical computed tomography was performed in 50 of 51 patients who underwent gastroenteric and hepatic surgeries. Twenty-eight, eighteen and four patients suffering from colorectal cancer, gastric cancer, and liver cancer respectively underwent colorectal surgery (laparoscopic surgery: 6 cases), gastrectomy, and hepatectomy. Three-dimensional computed tomography imaging of the inferior mesenteric artery, celiac artery and hepatic artery was performed. And in the follow-up examination of postoperative patients, multiplanar reconstruction image was made in case of need.

RESULTS: Scans in 50 patients were technically satisfactory and included in the analysis. Depiction of major visceral arteries, which were important for surgery and other treatments, could be done in all patients. Preoperative visualization of the left colic artery and sigmoidal arteries, the celiac artery and its branches, and hepatic artery was very useful to lymph node dissection, the planning of a reservoir and hepatectomy. And multiplanar reconstruction image was helpful to diagnosis for the postoperative follow-up of patients.

CONCLUSION: Three-dimensional volume rendering or multiplanar reconstruction imaging performed by multislice computed tomography was very useful for gastroenteric and hepatic surgeries.

Current standards of surgery for pancreatic cancer

Background

Pancreatic cancer carries a dismal prognosis but there has been a vast increase in evidence on its management in the past decade.

Methods

An electronic and manual search was performed for articles on the surgical treatment of pancreatic cancer published in the past 10 years.

Results

Six major areas of advancement were identified. Groups at high risk of developing pancreatic cancer, notably those with chronic pancreatitis and hereditary pancreatitis, have been defined, raising the need for secondary screening. Methods of staging pancreatic cancer for resection have greatly improved but accuracy is still only 85–90 per cent. Pylorus-preserving partial pancreatoduodenectomy without extended lymphadenectomy is the simplest procedure; it does not compromise long-term survival. Adjuvant chemotherapy significantly improves long-term survival. Patients who are free from major co-morbidity have better palliation by surgery (with a double bypass) than by endoscopy. High-volume centres improve the results of surgery for all outcome measures including long-term survival.

Conclusion

The surgical management of pancreatic cancer has undergone a significant change in the past decade. It has moved away from no active treatment. The standard of care can now be defined as potentially curative resection in a specialist centre followed by adjuvant systemic chemotherapy.

Vascular involvement in pancreatic neoplasm: a comparison between spiral CT and DSA

The principal criterion for resectability of pancreatic carcinoma is the assessment of vascular involvement. In a prospective evaluation the ability of Spiral CT Angiography (CTA) to detect vascular involvement in 50 patients with pancreatic carcinoma, was proved; DSA was performed later in all patients. In 20 patients, without vascular involvement, a complete concordance was obtained. Of 30 patients with vascular involvement, there was complete concordance between CTA and angiography in 22 patients and discordance in 8 patients. CTA was superior in 2 cases with periadventitial infiltration and in 5 patients with splenoportal confluence thrombosis. DSA was superior in 1 case with infiltration of the superior mesenteric vein. After surgical evaluation, sensitivity of CTA and DSA was 97% and 77%, respectively, and the negative predictive values were 95% and 74%. As compared to DSA, CTA is more rapid and less invasive and can be considered the modality of choice for preoperative work-up of pancreatic neoplasm.

Very-high-flow injection rate for upper abdominal CT angiography

BACKGROUND

The purpose of this study was to compare a very-high-flow injection-rate method (group A) and a conventional injection-rate method (group B) for visualization of upper abdominal arteries by multidetector helical computed tomography (MDHCT).

METHODS

The subjects were 240 patients suspected to have abdominal lesions. They were randomly assigned to group A (120 patients) and group B (120 patients). In group A, the bilateral medial cubital veins were punctured, and contrast medium was infused at a rate of 8.6-9.6 ml/s. In group B, the unilateral medial cubital vein was punctured, and contrast medium was infused at a rate of 2.0-3.0 ml/s. The quality of vascular visualization was graded as poor, good, or excellent by three radiologists.

RESULTS

All visualizations of the celiac trunk (CE) and superior mesenteric artery (SMA) were graded as excellent in both group A and group B. Visualization grades of the subsegmental branches of the hepatic artery (HA), right gastric artery (RGA), cystic artery, dorsal pancreatic artery (DPA), and superior pancreaticoduodenal artery (SPDA) were good or excellent, in 75% (paging method)/53.3% (three-dimensional method), 85%/30%, 77.7%/18.3%, 76.7%/28.3%, and 88.3%/42.5%, respectively, in group A, and 33.3%/11.7%, 46.7%/3.4%, 41.6%/5%, 55%/4.2%, and 72.5%/14.2%, respectively, in group B. The appearance rate of intrahepatic portal branches was 28.3% in group A and 66.7% in group B in the arterial dominant phase.

CONCLUSION

Group A showed better visualization results than Group B in upper abdominal arteries according to MDHCT.

Vascular anatomy of the pancreas and clinical applications

The development of recent technology, especially the helical computed tomography (CT) scan, allows us to observe small peripancreatic vessels which previously could be demonstrated only by angiography (1), and therefore make three-dimensional (3-D) volume rendered CT angiographic reconstruction possible (2). The neighboring structures as well as the pancreatic vessels are clearly visualized on the axial CT scan. Therefore, it is necessary to define the peripancreatic vessels on the axial images, as well as on angiography to make an accurate diagnosis of pancreatic disease so that we can also estimate the dynamic flow of the peripancreatic vessels. In this chapter, I would like to use the cadaver dissections of pancreatic vessels to explain each pancreatic vessel based on previous anatomic and radiologic references and finally demonstrate the clinical cases in terms of the pancreatic vessels. The pancreatic arteries and veins are explained based on the anatomic and radiologic references. Principal pancreatic vessels are demonstrated on cadaver dissection. The pancreas head is supplied by the anterior and posterior pancreaticoduodenal arteries forming arcades in the pancreaticoduodenal sulcus and is drained by the pancreaticoduodenal veins. The pancreas body and tail are supplied by the dorsal, inferior, and caudate pancreatic arteries, and are drained by the inferior and left pancreatic veins. Clinical applications in terms of the pancreatic vessels such as basis for interpretation of the angiography and the CT scan, treatment of pancreatitis and pancreatic cancer, detection of small insulinoma are stated.

Imaging pancreatic cancer: the role of multidetector CT with three-dimensional CT angiography

Over the past two decades, there have been significant technical advancements in computed tomography (CT). This has allowed CT to remain the gold standard for the evaluation of pancreatic pathology despite the advent of other imaging modalities, including MRI, PET and endoscopic ultrasound. Initially, CT scanners could only obtain 10-mm-thick slices at a rate of 4 slices per minute. Today, the current state of the art is multidetector CT (MDCT) technology, which allows the entire pancreas to be imaged by 1-mm slices in under 20 s. In addition, these new scanners allow true volume acquisition. The resultant data sets can be displayed not only as axial slices but also as a three-dimensional (3D) volume. The detail of these reconstructions when performed with volume rendering and maximum intensity projection techniques allows a detailed vascular mapping with accuracy that may exceed classic angiography. The use of thin collimation and dual-phase acquisition also improves the detection of hepatic metastasis as well as other sites of extrapancreatic disease. This article reviews the current state of the art of pancreatic imaging with specific emphasis on the use of MDCT, volume acquisitions and 3D arterial- and venous-phase vascular mapping. The advantages of these techniques and their impact on diagnosis and patient management are also addressed.

Multi-detector row helical CT angiography of hepatic vessels: depiction with dual-arterial phase acquisition during single breath hold

PURPOSE

To determine by using multi-detector row computed tomography (CT), in a triphasic hepatic dynamic study, which included single breath-hold dual-arterial phase acquisition, the accuracy and frequency of visualization of the small hepatic arterial and portal venous anatomy with angiographic correlation.

MATERIALS AND METHODS

In 62 patients, pre- and postcontrast triphasic helical CT were performed by using a multi-detector row CT scanner, with 2.5-mm detector row collimation, at a pitch of 6. The first and second arterial phases were performed during a single breath hold. One reader, blinded to the results of the angiography, reviewed the first arterial phase images on a cine display to assess hepatic arterial anatomy. Visualization of the portal vein and its branches was assessed by using second arterial and portal venous phase images.

RESULTS

Major arterial trunks (celiac, hepatic, superior mesenteric, and left gastric) were depicted in all cases. Visualization of small arteries was as follows: right and left hepatic, 62 (100%) of 62; middle hepatic, 52 (87%) of 60; cystic, 47 (90%) of 52; right gastric, 50 (89%) of 56; and right and left inferior phrenic, 57 (92%) and 55 (89%) of 62, respectively. Subsegmental or more peripheral branches of the portal vein were depicted in 83% of cases during the second arterial phase and in 96% during the portal phase. There was no difference in degree of visualization in these two phases.

CONCLUSION

Multi-detector row CT angiography was able to depict the hepatic vascular anatomy.

Pancreatic cancer: the bigger picture

Despite accurate diagnosis, better radiologic techniques, and safer surgery, long-term survival after surgical therapy for pancreatic cancer is disappointing. Median survival following pancreaticoduodenal resection is 12 to 15 months independent of surgical expertise, hospital size, or technical factors. Subsets of favorable tumors and longer survival times after surgery have been defined and include: small tumor size and low-grade lesions, tumor-free margins, and absence of nodal, venous, or perineural invasion; however, long-term survivors of pancreatic cancer may have none of these favorable features, and their tumors commonly manifest the most adverse tumor prognostic features. The converse that small-sized, histologically favorable tumors result in long-term survivors, also is not true. Five-year survival rates average 5% or less after all resections. In a large series in which 118 pancreatic resections were performed in 684 evaluated patients over a 6-year period, there were 12 5-year survivors, 5 of whom died in the sixth year. A report of 10-year survivors after surgery numbered 13 patients. The best actual 5-year survival rate was reported by Trede et al. Of the 37, 5-year survivors from a cohort of 118 patients, more than half died of cancer. This far exceeds any other actual survival rate and may be explained by a smaller tumor size. Farnell et al reported a 5-year survival rate difference (i.e., actuarial survival) in a subset of 174 resected patients with adenocarcinoma without perineural or duodenal invasion and with negative nodes (23% versus 6.8%), respectively. An impressive, large series of 616 patients with resected adenocarcinoma of the pancreas who underwent PDR (85%), distal pancreatectomy (9%), and total pancreatectomy (6%), has been reported. The mortality rate was 2.1%, and postoperative complications occurred in 30%. The five-year survival rate was 15%. The author's best result was observed among 20 initially "unresectable" patients who were treated with chemoradiation therapy, followed by tumor extirpation. Among the 18 surgical survivors there are seven five-year survivors, three of whom are in their tenth year of survival. They are discussed in the article by Cooperman et al ("Long-term Follow-up...") elsewhere in this issue.

Multidetector CT angiography in the evaluation of pancreatic carcinoma: preliminary observations

Multidetector CT (MDCT) provides unparalleled capabilities for combining narrow scan collimation with rapid data acquisition protocols. When combined with CT angiographic techniques and 3D-volume rendering we are able to create unique displays for evaluating a range of clinical pathologies. In this pictorial review we present the potential advantages of using MDCT angiography for the evaluation of pancreatic cancer and its role in the accurate staging of these patients. The use of dual-phase CT scanning in both the arterial phase and portal phase is addressed with the role of 3D CT angiography clearly defined. Numerous case studies are presented to show the advantages of these techniques over simple axial CT imaging.

Cystic dystrophy of the duodenal wall in the heterotopic pancreas: radiopathological correlations

PURPOSE

The purpose of this work was to correlate the CT features of cystic dystrophy in heterotopic pancreas (CDHP) with pathological features.

METHODS

Patients were selected from 190 patients who underwent pancreatico-duodenectomy over a 10 year period in our institution. CT findings were retrospectively analyzed in 20 cases and correlated with pathological findings.

RESULTS

Lesions were found to be located in the inner part of the second portion of the duodenum in all except one case. In all cases, the duodenal wall was thickened, both at CT and at histopathological examination, and moderate to strong contrast enhancement of the duodenal wall was noted at CT in all cases but one. Cysts were multiple in all cases. No heterotopic pancreas was identified with CT. Inflammatory changes with or without enlarged nodes were detected on CT in 15 of 20 cases. Chronic pancreatitis was present in 10 cases at pathology, including 5 cases with calcifications. The radiopathological correlation was excellent for all criteria but two: the size of the cysts and the extent of pyloric involvement.

CONCLUSION

In patients with CDHP, CT features correlate well with pathological results. Multiple cysts located in an enlarged duodenal wall with postcontrast enhancement and inflammatory changes are strongly suggestive of CDHP.

The role of transabdominal ultrasonography, helical computed tomography, and magnetic resonance cholangiopancreatography in diagnosis and management of pancreatic disease

Many technical advances have offered enhanced capabilities in noninvasive imaging of the pancreas. Although these technical advances are impressive, current studies do not always define clearly the benefits that these advances will confer in patient management. A critical overview of these imaging modalities is offered here, with respect to diagnosis and patient management. Outcomes from various studies are summarized for modalities including transabdominal ultrasound, computed tomography, magnetic resonance imaging with and without pancreatography, and positron emission tomography.

Pancreatic imaging. New modalities

This article discusses the techniques and applications of the newest pancreatic cross-sectional imaging modalities. The specific modalities that are discussed include helical computed tomography with dual phase imaging and three-dimensional computer rendering techniques, magnetic resonance imaging and magnetic resonance cholangiopancreatography, endoscopic and intraductal pancreatic sonography, and radionuclide scintigraphy using positron emission scanning and somatostatin-receptor imaging.