MRI features of groove pancreatitis

Groove pancreatitis presenting with upper gastrointestinal obstruction and abnormal renal function: A case report and literature review

Groove pancreatitis (GP) is a rare type of chronic pancreatitis characterized by fibrotic lesions localized to the groove between the pancreatic head, duodenum, and common bile duct. We present a case of a 59-year-old male alcoholic with vomiting and renal dysfunction found to have duodenal obstruction and low-density pancreatic head lesions on computed tomography concerning for GP. The patient underwent pancreaticoduodenectomy and pathology confirmed the diagnosis postoperatively. The patient recovered well without complications or relapse at follow-up. Although rare, GP should be included in the differential for pancreatic head masses in middle-aged alcoholics and surgical resection may be necessary for symptom relief and exclusion of malignancy.

Diagnostic value of endoscopic ultrasound in groove pancreatitis

Aim: Groove pancreatitis (GP) is a rare type of chronic pancreatitis characterized by varying degrees of thickening and scarring of the duodenal wall, duodenal lumen stenosis, mucosal hypertrophy with plicae and cyst formation. GP is primarily observed in middle-aged male patients with a history of alcohol consumption. Clinical symptoms are usually non-specific, and there is currently no unified diagnostic standard. However, imaging methods, particularly endoscopic ultrasound (EUS), are useful for diagnosis. EUS-guided biopsy can provide a strong basis for the final diagnosis. This review summarizes the value of EUS and its derivative technologies in the diagnosis, differential diagnosis and treatment of GP.Methods: After searching in PubMed and Web of Science databases using 'groove pancreatitis (GP)' and 'endoscopic ultrasonography (EUS)' as keywords, studies related were compiled and examined.Results: EUS and its derivative technologies are of great significance in the diagnosis, differential diagnosis, and treatment of GP, but there are still limitations that need to be comprehensively applied with other diagnostic methods to obtain the most accurate results.Conclusion: EUS has unique value in both the diagnosis and treatment of GP. Clinicians need to be well-versed in the advantages and limitations of EUS for GP diagnosis to select the most suitable imaging diagnostic method for different cases and to reduce the unnecessary waste of medical resources.

Pancreatic cancer, autoimmune or chronic pancreatitis, beyond tissue diagnosis: Collateral imaging and clinical characteristics may differentiate them

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies and is developing into the 2^nd leading cause of cancer-related death. Often, the clinical and radiological presentation of PDAC may be mirrored by other inflammatory pancreatic masses, such as autoimmune pancreatitis (AIP) and mass-forming chronic pancreatitis (MFCP), making its diagnosis challenging. Differentiating AIP and MFCP from PDAC is vital due to significant therapeutic and prognostic implications. Current diagnostic criteria and tools allow the precise differentiation of benign from malignant masses; however, the diagnostic accuracy is imperfect. Major pancreatic resections have been performed in AIP cases under initial suspicion of PDAC after a diagnostic approach failed to provide an accurate diagnosis. It is not unusual that after a thorough diagnostic evaluation, the clinician is confronted with a pancreatic mass with uncertain diagnosis. In those cases, a re-evaluation must be entertained, preferably by an experienced multispecialty team including radiologists, pathologists, gastroenterologists, and surgeons, looking for disease-specific clinical, imaging, and histological hallmarks or collateral evidence that could favor a specific diagnosis. Our aim is to describe current diagnostic limitations that hinder our ability to reach an accurate diagnosis among AIP, PDAC, and MFCP and to highlight those disease-specific clinical, radiological, serological, and histological characteristics that could support the presence of any of these three disorders when facing a pancreatic mass with uncertain diagnosis after an initial diagnostic approach has been unsuccessful.

Surgical Management of Groove Pancreatitis: A Case Report

Groove pancreatitis (GP) is a chronic type of pancreatitis involving the groove area between the head of the pancreas, the duodenum, and the common bile duct. Alcohol abuse is one of the main pathogenetic factors, although its etiology is not clearly defined. Differential diagnosis of pancreatic disorders remains difficult. The lack of diagnostic management and the restrictive number of patients are the main barriers. This article presents a case of a 37-year-old male diagnosed with GP after several episodes of epigastric pain and vomiting, with a history of chronic alcohol consumption. The patient's radiological and laboratory results excluded the possibility of malignancy and suggested the diagnosis of groove pancreatitis with duodenal stenosis. After initial conservative treatment failed, surgical management was decided. A gastroenteroanastomosis was made in order to bypass the duodenum aiming for a total resolution of the symptoms and an uneventful recovery of the patient. Although most studies suggest pancreatoduodenectomy (Whipple's procedure) as the treatment of choice, a less major procedure can be performed in evidence of malignancy absence.

Groove Pancreatitis-Tumor-like Lesion of the Pancreas

Groove pancreatitis (GP) is an uncommon appearance of pancreatitis represented by fibrous inflammation and a pseudo-tumor in the area over the head of the pancreas. The underlying etiology is unidentified but is firmly associated with alcohol abuse. We report the case of a 45-year-old male patient with chronic alcohol abuse who was admitted to our hospital with upper abdominal pain radiating to the back and weight loss. Laboratory data were within normal limits, except for the level of carbohydrate antigen (CA) 19-9. An abdominal ultrasound and computed tomography (CT) scan revealed swelling of the pancreatic head and duodenal wall thickening with luminal narrowing. We performed an endoscopic ultrasound (EUS) with fine needle aspiration (FNA) from the markedly thickened duodenal wall and the groove area, which revealed only inflammatory changes. The patient improved and was discharged. The principal objective in managing GP is to exclude a diagnosis of malignancy, whilst a conservative approach might be more acceptable for patients instead of extensive surgery.

Groove Pancreatitis: A Case Report and Review of a Hidden Type of Chronic Pancreatitis

Groove pancreatitis is a chronic type of segmental or focal pancreatitis seen to affect the groove, which is the region between the head of the pancreas, the duodenum, and the common bile duct. Despite its incidence remaining unknown, it accounts for 2.7% to 24.5% of pancreaticoduodenectomies performed for chronic pancreatitis. A diverse etiology has been implicated but the exact cause is yet to be identified. As it closely mimics pancreatic malignancy and remains mostly undiagnosed preoperatively, many patients often end up undergoing a pancreaticoduodenectomy. Awareness of this entity and early diagnosis will help us address this issue with more conservative measures than by resorting to a morbid procedure such as a pancreaticoduodenectomy.

We report a case of a 50-year-old male, a chronic alcoholic, with a two-year history of upper abdominal pain, postprandial vomiting, and weight loss. An abdominal contrast-enhanced computed tomography (CECT) scan was suggestive of either a pancreatic malignancy or a possibility of groove pancreatitis. However, postoperative histopathological examination confirmed the lesser known groove pancreatitis. Here, we review the clinical, radiological, and pathological characteristics of groove pancreatitis, as its diagnosis and management still pose a challenge.

Pancreatoduodenectomy for paraduodenal pancreatitis: a diagnostic and therapeutic challenge

Paraduodenal pancreatitis (PP) is a rare type of focal pancreatitis involving the groove space. It mimics pancreatic head carcinoma, and its diagnosis and treatment are challenging. Pancreatoduodenectomy (PD) has traditionally been the primary surgical treatment for duodenal stenosis or suspected cancer.

We herein report a case of PP in a 65-year-old man. The patient was admitted to the hospital for postprandial epigastric pain and vomiting. A low-density mass between the uncinate process of the pancreas and the horizontal segment of the duodenum was suspected based on computed tomography findings. Both upper gastrointestinal radiography and gastrointestinal endoscopy showed an obstruction of the distal part of the descending duodenum. An operation was performed to release the obstruction and obtain a definitive diagnosis. A 3-cm mass in the groove area was compressing the third part of the duodenum, and PD was empirically performed. The final histopathological diagnosis was PP. Postoperatively, the patient developed anastomotic leakage of the gastrojejunostomy site with bleeding and was eventually discharged on postoperative day 51 after emergency surgery.

PP should be considered as a differential diagnosis of pancreatic ductal adenocarcinoma or duodenal stenosis, and accurate preoperative diagnosis preserves the opportunity for conservative or endoscopic management.

Groove Pancreatitis Associated with Transient Liver Injury Mimicking Ampullary Neoplasm

Groove pancreatitis is an unusual form of pancreatitis characterized by fibrous inflammation and pseudo-tumor in the area around the head of the pancreas. The underlying etiology is unknown but is strongly linked to alcohol abuse. We report a 52-year-old male smoker with hypertension, asthma, and alcohol abuse who was admitted with severe epigastric pain radiating to the back. He was found to have acute pancreatitis. A computed tomography scan of the abdomen showed a mass lesion in the peri-ampullary region. MRI of the abdomen revealed dilated common bile duct and duodenal mass and features suggestive of groove pancreatitis. During the hospital stay, bilirubin and liver enzymes started to rise and then decreased gradually to the previous normal range. The secondary workup for liver disease was unremarkable. The patient improved and was discharged. Six-month follow-up showed regression of the duodenal lesion and reduction in the common bile duct dilatation. Excluding malignancy remains the main challenge in managing groove pancreatitis, and a conservative approach is more reasonable in cases with a typical profile.

Inflammatory mimickers of pancreatic adenocarcinoma

Pancreatic ductal adenocarcinoma can be a difficult imaging diagnosis early in its course given its subtle imaging findings such as focal pancreatic duct dilatation, abrupt duct cut-off, and encasement of vasculature. A variety of pancreatitidies have imaging findings that mimic pancreatic ductal adenocarcinoma and lead to mass formation making diagnosis even more difficult on imaging alone. These conditions include acute focal pancreatitis, chronic pancreatitis, autoimmune pancreatitis, and paraduodenal ("groove") pancreatitis. This review will focus on imaging findings that can help differentiate these inflammatory processes from pancreatic ductal adenocarcinoma.

Imaging diagnosis and staging of pancreatic ductal adenocarcinoma: a comprehensive review

Pancreatic ductal adenocarcinoma (PDAC) has continued to have a poor prognosis for the last few decades in spite of recent advances in different imaging modalities mainly due to difficulty in early diagnosis and aggressive biological behavior. Early PDAC can be missed on CT due to similar attenuation relative to the normal pancreas, small size, or hidden location in the uncinate process. Tumor resectability and its contingency on the vascular invasion most commonly assessed with multi-phasic thin-slice CT is a continuously changing concept, particularly in the era of frequent neoadjuvant therapy. Coexistent celiac artery stenosis may affect the surgical plan in patients undergoing pancreaticoduodenectomy. In this review, we discuss the challenges related to the imaging of PDAC. These include radiological and clinical subtleties of the tumor, evolving imaging criteria for tumor resectability, preoperative diagnosis of accompanying celiac artery stenosis, and post-neoadjuvant therapy imaging. For each category, the key imaging features and potential pitfalls on cross-sectional imaging will be discussed. Also, we will describe the imaging discriminators of potential mimickers of PDAC.

Pancreaticoduodenectomy for paraduodenal pancreatitis is associated with a higher incidence of diabetes but a similar quality of life and pain control when compared to medical treatment

BACKGROUND

Paraduodenal pancreatitis is a focal form of chronic pancreatitis that affects the groove area between the duodenum and the head of the pancreas. Consensus regarding surgical or nonsurgical management as the best treatment option is still lacking.

METHODS

We retrospectively evaluated all patients managed for PP at The Pancreas Institute of the University Hospital Trust of Verona from 1990 to 2017. The outcomes of surgical vs. medical treatment with regard to pain control, quality of life and pancreatic insufficiency were evaluated through specific questionnaires.

RESULTS

The final study population consisted of 75 patients: 62.6% underwent surgery, and 37.4% were managed without surgery. All surgical procedures consisted of pancreaticoduodenectomy. The median follow-up from the diagnosis of paraduodenal pancreatitis was 60 (12-240) months. Patients who underwent surgery experienced a similar incidence of steatorrhea (44.7 vs. 52.6%; p = 0.4) but a significantly higher incidence of diabetes (59.6 vs. 10.7%; p < 0.01) when compared to those managed without surgery. There was no difference in terms of reported chronic pain (Graded Chronic Pain Scale, median 0 vs. 1; p = 0.1) and quality of life (Pancreatitis QoL Instrument, median 82 vs. 79; p = 0.2). However, surgical patients reported a worse level of self-care activities associated with glycemic control (Diabetes Self-Management Questionnaire, median 20 vs. 28, p = 0.02).

CONCLUSION

In patients affected by paraduodenal pancreatitis, surgery and medical therapy seem to obtain similar results in terms of quality of life and pain control. However, surgery is associated with an increased prevalence of postoperative diabetes with consequent relevant issues with self-care management. Surgery should be considered only in selected patients after adequate medical treatment.

Paraduodenal Pancreatitis: A Deceptive Abdominal Mass with Unique Histologic Findings

Paraduodenal pancreatitis (PP) is an uncommon abdominal pathology characterized by scarring of the pancreaticoduodenal space. Diagnosis of this inflammatory process is challenging as its clinical presentation is similar to that of pancreatic cancer. Currently, no definitive radiologic or pathologic features have been established to permit diagnosis of PP without surgical resection. However, the presence of eosinophilic concretions has been reported with increasing frequency in the histologic evaluation of PP. To the best of our knowledge, these concretions are distinctive for PP and not reported in neoplasms commonly involving the pancreaticoduodenal space. Herein, we discuss the case of a 60-year-old man who was found to have PP after pancreaticoduodenectomy for a paraduodenal mass with an initially nondiagnostic biopsy. Retrospective review of the preoperative FNA samples revealed eosinophilic concretions like those found in the final surgical specimen. If the identification of eosinophilic concretions in a background of inflammatory changes was to be accepted as a diagnostic criterion for PP, patients such as ours could be spared the morbidity associated with surgical resection.

Groove pancreatitis: a challenging imaging diagnosis

Groove pancreatitis (GP) is an uncommon form of chronic pancreatitis (CP) involving the space between duodenum, pancreatic head and common bile duct (CBD) known as pancreatic-duodenal groove. Although an association with long-standing ethanol assumption is reported a definite etiology of GP is unknown. Since thickening of the duodenal wall, pancreatic head enlargement, CBD stricture and dilatation of pancreatic duct system are common findings the differential diagnosis with pancreatic head neoplasm by means of imaging can be challenging. However, some imaging findings such as fibrotic changes of the pancreatic groove and presence of duodenal wall cysts may suggest the correct diagnosis. In this paper we review clinical and imaging features of GP with emphasis on computed tomography (CT) and magnetic resonance imaging (MRI) findings.

Imaging in chronic pancreatitis: State of the art review

Chronic pancreatitis (CP) is an important gastrointestinal cause of morbidity worldwide. It can severely impair the quality of life besides life-threatening acute and long-term complications. Pain and pancreatic exocrine insufficiency (leading to malnutrition) impact the quality of life. Acute complications include pseudocysts, pancreatic ascites, and vascular complications. Long-term complications are diabetes mellitus and pancreatic cancer. Early diagnosis of CP is crucial to alter the natural course of the disease. However, majority of the cases are diagnosed in the advanced stage. The role of various imaging techniques in the diagnosis of CP is discussed in this review.

MRI evaluation of pancreatic ductal adenocarcinoma: diagnosis, mimics, and staging

The radiologist's role in the evaluation of pancreatic ductal adenocarcinoma remains critical in the management of this deadly disease. Imaging plays a vital role in the diagnosis and staging of pancreatic cancer. Although CT is more commonly used for staging pancreatic cancer, MR is increasingly playing an important role in this regard. In our institution, all pancreatic malignancies undergo staging with MRI. In this pictoral essay, we illustrate the MR imaging features of pancreatic ductal adenocarcinoma and its mimics, and we also discuss pearls and pitfalls in MR staging of pancreatic carcinoma.

Pancreaticoduodenectomy and Outcomes for Groove Pancreatitis

BACKGROUND/AIMS

The operative management of groove pancreatitis (GP) is still a matter of controversy and pancreaticoduodenectomy (PD) can be a high-risk procedure for patients. The aim of this study was to report our 9-year experience of surgical resection for GP and to review relevant literature.

METHODS

A retrospective review of patients undergoing pancreatectomy for GP from August 1, 2008, through May 31, 2017 was performed. Patients with clinical, radiologic, and final pathologic confirmation of GP were included. Literature on the current understanding of GP was reviewed.

RESULTS

Eight patients from total 449 pancreatectomies met inclusion criteria. Four male and 4 female patients (mean age, 51.9 years; mean body mass index, 25.3) underwent pylorus-preserving pancreatoduodenectomy (3 by laparoscopy and 5 by open approach). Mean (range) operative time and blood loss was 343 (167-525) min and 218 (40-500) mL respectively. Pancreatic fistula and delayed gastric emptying were noted in one patient each. No major complications occurred, but minor complications occurred in 5 (62%) patients. Mean hospital stay was 6.1 (range 3-14) days. At median follow-up of 18.15 (interquartile range 7.25-33.8) months, all patients experienced a resolution of pancreatitis and improvement in symptoms.

CONCLUSIONS

PD is a safe procedure for GP. Short-term surgical outcomes are acceptable and long-term outcomes are associated with improved symptom control.

Paraduodenal pancreatitis: benign and malignant mimics at MRI

Paraduodenal pancreatitis, also known as groove pancreatitis, is a rare form of chronic pancreatitis that masquerades as pancreatic adenocarcinoma affecting the pancreaticoduodenal groove, a potential space between the head of the pancreas, duodenum, and common bile duct. Two forms of groove pancreatitis have been described. The segmental form involves the pancreatic head with development of scar tissue within the groove, whereas the pure form affects the groove only, sparing the pancreatic head. Imaging findings of groove pancreatitis often overlap with primary duodenal, ampullary, or pancreatic neoplasms, which often results in a diagnostic challenge. In addition, paraduodenal pancreatitis can be mistaken for cystic pancreatic lesions, especially when there is involvement of the duodenal wall. Preoperative recognition of this entity is very important in order to avoid unnecessary procedures, although surgery, such as pancreaticoduodenectomy, may still be required to relieve obstructive symptoms. In this article, the pathophysiology and magnetic resonance imaging characteristics of paraduodenal pancreatitis and important benign and malignant mimics are discussed.

Heterotopic Pancreas: Histopathologic Features, Imaging Findings, and Complications

Heterotopic pancreas is a congenital anomaly in which pancreatic tissue is anatomically separate from the main gland. The most common locations of this displacement include the upper gastrointestinal tract-specifically, the stomach, duodenum, and proximal jejunum. Less common sites are the esophagus, ileum, Meckel diverticulum, biliary tree, mesentery, and spleen. Uncomplicated heterotopic pancreas is typically asymptomatic, with the lesion being discovered incidentally during an unrelated surgery, during an imaging examination, or at autopsy. The most common computed tomographic appearance of heterotopic pancreas is that of a small oval intramural mass with microlobulated margins and an endoluminal growth pattern. The attenuation and enhancement characteristics of these lesions parallel their histologic composition. Acinus-dominant lesions demonstrate avid homogeneous enhancement after intravenous contrast material administration, whereas duct-dominant lesions are hypovascular and heterogeneous. At magnetic resonance imaging, the heterotopic pancreas is isointense to the orthotopic pancreas, with characteristic T1 hyperintensity and early avid enhancement after intravenous gadolinium-based contrast material administration. Heterotopic pancreatic tissue has a rudimentary ductal system in which an orifice is sometimes visible at imaging as a central umbilication of the lesion. Complications of heterotopic pancreas include pancreatitis, pseudocyst formation, malignant degeneration, gastrointestinal bleeding, bowel obstruction, and intussusception. Certain complications may be erroneously diagnosed as malignancy. Paraduodenal pancreatitis is thought to be due to cystic degeneration of heterotopic pancreatic tissue in the medial wall of the duodenum. Recognizing the characteristic imaging features of heterotopic pancreas aids in differentiating it from cancer and thus in avoiding unnecessary surgery. ^© RSNA, 2017.

Paraduodenal pancreatitis as a mimicker of pancreatic adenocarcinoma: MRI evaluation

PURPOSE

To evaluate the MRI features of paraduodenal pancreatitis (PDP) and to define useful signs to differentiate PDP from pancreatic ductal adenocarcinoma (PDAC).

MATERIAL AND METHODS

We reviewed the MRI scans of 56 patients, 28 affected by PDP and 28 by PDAC, all pathologically proven. The following parameters were evaluated: signal intensity of the lesion on T1-, T2-WI, DWI (b800) and after contrast medium administration; presence of cysts; dilation of common hepatic duct and main pancreatic duct; focal thickening of the second portion of the duodenum; maximum diameter and volume of the lesion.

RESULTS

Both PDPs and PDACs were more frequently hypointense on T1-WI, iso-hyperintense on T2-WI, hypointense in the pancreatic phase and iso-hypointense in the venous phase (p>0.05); in the delayed phase most PDP were hyperintense (p=0.0031); on DWI 71.4% PDPs were isointense and all PDACs were hyperintense (p=0.0041). Cystic components were present in 85.7% PDPs (p=0.0011); double duct sign was present in 50% PDACs (p=0.0048); focal thickening of the duodenum was depicted in 89.3 PDPs (p=0.0012). PDPs were larger than PDACs (p=0.0003).

CONCLUSION

The most suggestive signs of PDP are: signal hyperintensity in the delayed phase, isointensity on DWI, presence of cysts, focal thickening of the duodenum and large size of the lesion.

Heterotopic pancreatic rests: imaging features, complications, and unifying concepts

OBJECTIVE

The spectrum of pancreatic heterotopia will be reviewed, including clinical features, potential complications, and imaging manifestations. This will also include a review of various entities associated with pancreatic heterotopia such as groove pancreatitis and cystic dystrophy of gastroduodenal heterotopic pancreas. These entities were previously thought of as distinct histopathologic entities but now appear to represent manifestations of pancreatic heterotopia.

CONCLUSION

Pancreatic heterotopia and heterotopic pancreatitis can have a wide range of appearances. Several entities, which were previously thought to be distinct, can be considered manifestations of pancreatic heterotopia and heterotopic pancreatitis.

Groove pancreatitis-a great mimicker

Groove pancreatitis is an uncommon form of chronic pancreatitis affecting the "groove" between the pancreatic head, duodenum and common bile duct. Many radiologists remain unfamiliar with this entity, with only a few descriptions of it existing in the radiology and pathology literature. The exact underlying cause of groove pancreatitis is unclear, although there are strong associations with peptic ulcer disease, smoking, long-term alcohol abuse, functional obstruction of the duct of Santorini and Brunner gland hyperplasia. This entity mimics pancreatic carcinoma and often ultimately leads to surgery. Hence it is important for radiologists to be familiar with imaging findings of groove pancreatitis to avoid diagnostic dilemma. Imaging findings in our case showed a soft tissue mass in the pancreaticoduodenal groove with enhancement, consistent with scar tissue and cystic changes within the lesion. It was associated with adjacent duodenal wall thickening with smooth and regular tapering of the pancreatic and common bile ducts.

Groove pancreatitis vs. pancreatic adenocarcinoma: A review of 8 cases

INTRODUCTION

Groove pancreatitis (PS) is an uncommon clinical situation and radiologically it can mimic carcinoma of the periampullary area. The aim of this paper is to study a series of 8 patients who underwent surgery with preoperative diagnosis of pancreatic head mass and subsequent pathological diagnosis of PS.

METHODS

In our series, 6 were men and 2 women, with an average age of 51,9 years. Before surgery, all patients had epigastric abdominal pain requiring analgesia at high doses. The preoperative analytical CEA and Ca 19.9 were normal in all patients. Imaging studies showed intrapancreatic solid lesions in 6 of the 8 patients, and in the remaining 2 one papillary mass of 5 and 6cm, respectively, that caused stenosis in the duodenal luz. EUS neoplastic cells were negative in all patients.

RESULTS

The immediate postoperative evolution was satisfactory, there are no complications. In our series, no patients have died. The long-term follow-up, in 7 of the 8 patients, has been excellent with disappearance of abdominal pain and improvement of nutritional status. The remaining patient had frequent recurrent episodes of acute pancreatitis, and at 60 months, presented a pseudocyst that has required a Roux-en-Y cystojejunostomy.

CONCLUSIONS

PS must be included in the differential diagnosis of pancreatic lesions, which may include carcinoma of the periampullary area and other causes of chronic pancreatitis.

Groove Pancreatitis: A Rare form of Chronic Pancreatitis

Context:

Groove pancreatitis is a rare form of chronic pancreatitis affecting the “groove” of the pancreas among the pancreatic head, duodenum, and common bile duct. The exact cause is unknown, although there are associations with long-term alcohol abuse, smoking, peptic ulcer disease, heterotopic pancreas, gastric resection, biliary disease, and anatomical or functional obstruction of the minor papilla. The diagnosis can be challenging. Endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography are the preferred imaging modalities. The treatment of choice is conservative although surgical intervention can sometimes be required.

Case Report:

A 57-year-old male with a history of human immunodeficiency virus and hepatitis B presented with 4 days of epigastric pain. Abdominal exam revealed absent bowel sounds and epigastric tenderness. He had a creatinine of 1.72 mg/dL, potassium of 2.9 mmol/L, and a normal lipase level of 86 U/L. Liver enzymes and total bilirubin were normal. Computed tomography abdomen showed high-grade obstruction of the second portion of the duodenum without any obvious mass. An esophagogastroduodenoscopy showed a mass at the duodenal bulb causing luminal narrowing, with biopsies negative for malignancy. Magnetic resonance imaging revealed a mass in the region of the pancreatic head and descending duodenum. EUS revealed a 3 cm mass in the region of pancreatic head with irregular borders and no vascular invasion. Fine needle aspiration (FNA) was nondiagnostic. The patient then underwent a Whipple's procedure. Pathology of these specimens was negative for malignancy but was consistent with para-duodenal or groove pancreatitis.

Conclusion:

The low incidence of groove pancreatitis is partly due to lack of familiarity with the disease. Groove pancreatitis should be considered in the differential for patients presenting with pancreatic head lesions and no cholestatic jaundice, especially when a duodenal obstruction is present, and neither duodenal biopsies nor pancreatic head FNA confirm adenocarcinoma.

Clinicoradiological appraisal of 'paraduodenal pancreatitis': Pancreatitis outside the pancreas!

Purpose:

Paraduodenal pancreatitis (PP) is a unique form of focal chronic pancreatitis that selectively involves the duodenum and aberrant pancreatic tissue located near the minor papilla (beyond the pancreas proper). The pseudotumoral nature of the disease often generates considerable clinical quandary and patient apprehension, and therefore merits a better understanding. The present study appraises the clinicoradiological manifestations of PP in 33 patients.

Materials and Methods:

Clinical, laboratory, and radiological manifestations of 33 patients of PP treated in gastroenterology/hepatology and hepato-pancreatico-biliary surgery units during June 2010-August 2014 were retrospectively reviewed.

Results:

All patients were young to middle-aged men (100%) with history of alcohol abuse (93.9%) and/or smoking (42.4%), who presented either with acute or gradually worsening abdominal pain (90.9%). Pancreatic enzymes and serum tumor markers remained normal or were mildly/transiently elevated. Cystic variant was detected in 57.6% (solid in 42.4%); the disease remained confined to the groove/duodenum (pure form) in 45.4%. Medial duodenal wall thickening with increased enhancement was seen in 87.87 and 81.81%, respectively, and duodenal/paraduodenal cysts were seen in 78.78%. Pancreatic calcifications and biliary stricture were seen 27.3% patients. Peripancreatic arteries were neither infiltrated nor encased.

Conclusion:

PP has a discrete predilection for middle-aged men with history of longstanding alcohol abuse and/or smoking. Distinguishing imaging findings include thickening of the pancreatic side of duodenum exhibiting increased enhancement with intramural/paraduodenal cysts. This may be accompanied by plate-like scar tissue in the groove region, which may simulate groove pancreatic carcinoma. However, as opposed to carcinoma, the peripancreatic arteries are neither infiltrated nor encased, rather are medially displaced.

Magnetic resonance imaging of pancreatitis: An update

Magnetic resonance (MR) imaging plays an important role in the diagnosis and staging of acute and chronic pancreatitis and may represent the best imaging technique in the setting of pancreatitis due to its unmatched soft tissue contrast resolution as well as non-ionizing nature and higher safety profile of intravascular contrast media, making it particularly valuable in radiosensitive populations such as pregnant patients, and patients with recurrent pancreatitis requiring multiple follow-up examinations. Additional advantages include the ability to detect early forms of chronic pancreatitis and to better differentiate adenocarcinoma from focal chronic pancreatitis. This review addresses new trends in clinical pancreatic MR imaging emphasizing its role in imaging all types of acute and chronic pancreatitis, pancreatitis complications and other important differential diagnoses that mimic pancreatitis.

Pancreatitis-imaging approach

Pancreatitis is defined as the inflammation of the pancreas and considered the most common pancreatic disease in children and adults. Imaging plays a significant role in the diagnosis, severity assessment, recognition of complications and guiding therapeutic interventions. In the setting of pancreatitis, wider availability and good image quality make multi-detector contrast-enhanced computed tomography (MD-CECT) the most used imaging technique. However, magnetic resonance imaging (MRI) offers diagnostic capabilities similar to those of CT, with additional intrinsic advantages including lack of ionizing radiation and exquisite soft tissue characterization. This article reviews the proposed definitions of revised Atlanta classification for acute pancreatitis, illustrates a wide range of morphologic pancreatic parenchymal and associated peripancreatic changes for different types of acute pancreatitis. It also describes the spectrum of early and late chronic pancreatitis imaging findings and illustrates some of the less common types of chronic pancreatitis, with special emphasis on the role of CT and MRI.

MR imaging of the pancreas

Magnetic resonance (MR) imaging of the pancreas is useful as both a problem-solving tool and an initial imaging examination of choice. With newer imaging sequences such as diffusion-weighted imaging, MR offers improved ability to detect and characterize lesions and identify and stage tumors and inflammation. MR cholangiopancreatography can be used to visualize the pancreatic and biliary ductal system. In this article, the use of MR to evaluate the pancreas, including recent advances, is reviewed and the normal appearance of the pancreas on different imaging sequences, as well as inflammatory diseases, congenital abnormalities, and neoplasms of the pancreas, are discussed.

Paraduodenal pancreatitis

Paraduodenal pancreatitis is a distinct clinicopathological entity involving the duodenum and the pancreatic tissue in the vicinity of the minor papilla. Most afflicted patients are young alcoholic males who present clinically with upper abdominal pain, weight loss, nausea, and vomiting. Pancreatic tissue elements in the duodenal wall and impedance to exocrine pancreatic secretions at the minor papilla are key factors in the pathogenesis of this condition. On imaging, the condition may manifest as a solid fibrotic mass around the minor papilla or as cysts in the duodenum and the pancreaticoduodenal groove. Duodenal stenosis, biliary strictures, chronic calcifying pancreatitis, and pancreatic ductal dilatation are also often observed.

Groove pancreatitis: spectrum of imaging findings and radiology-pathology correlation

OBJECTIVE

Groove pancreatitis is a rare form of chronic pancreatitis affecting the "groove" between the pancreatic head, duodenum, and common bile duct. The exact cause is unknown, although there are strong associations with long-term alcohol abuse, functional obstruction of the duct of Santorini, and Brunner gland hyperplasia.

CONCLUSION

Unfortunately, differentiating groove pancreatitis from malignancy on the basis of imaging features, clinical presentation, or laboratory markers can be extraordinarily difficult, and the vast majority of these patients ultimately undergo a pancreaticoduodenectomy (Whipple procedure) because of an inability to completely exclude malignancy. In certain cases, however, the imaging features on CT and MRI can allow the radiologist to prospectively suggest the correct diagnosis.

Paraduodenal pancreatitis: clinical performance of MR imaging in distinguishing from carcinoma

PURPOSE

To evaluate the diagnostic performance of contrast material-enhanced magnetic resonance (MR) imaging for distinguishing paraduodenal pancreatitis (PDP) from pancreatic head duct adenocarcinoma (CA) in patients with diagnoses confirmed by histopathologic analysis.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board and is HIPAA compliant. Between July 2007 and July 2010, 47 patients who underwent Whipple procedure and MR imaging less than 60 days before surgery were identified retrospectively. Two relatively inexperienced fellowship trainees with 9 months of body fellowship training were asked to record the presence or absence of three MR imaging features: focal thickening of the second portion of the duodenum; abnormal enhancement of the second portion of the duodenum; and cystic focus in the expected region of the accessory pancreatic duct. Strict criteria for diagnosis of PDP included presence of all three imaging features. Any case that did not fulfill the criteria was classified as CA. Sensitivity, specificity, positive predictive value, and negative predictive value for characterization of PDP was calculated for each reader with 95% confidence intervals. A κ test assessed level of agreement between readers.

RESULTS

Each reader correctly categorized 15 of 17 (88.2%) PDP cases when all three imaging criteria were met. Alternatively, 26 of 30 (86.7%) pancreatic duct CA were correctly categorized as inconsistent with PDP. Four patients with histopathologic diagnosis of CA were incorrectly classified as PDP by each reader. Agreement between the two readers showed substantial κ agreement for the diagnosis of PDP and differentiation from pancreatic duct CA.

CONCLUSION

Contrast-enhanced MR imaging may help accurately identify PDP and distinguish it from CA when strict diagnostic criteria are followed.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13112056/-/DC1.

Fine-needle aspiration features of paraduodenal pancreatitis (groove pancreatitis): a report of three cases

Chronic pancreatitis is notorious for mimicking both the clinical and radiologic presentation of pancreatic carcinoma. Paraduodenal pancreatitis is believed to result from focal chronic pancreatitis which affects the minor papilla of the duodenum. Currently, there is limited information available regarding the cytologic features of paraduodenal pancreatitis. In this study, we report the cytologic features of three patients with paraduodenal pancreatitis who had EUS-guided FNAs of the pancreas. The cytologic features were highly variable between cases, likely due to sampling of the various components of paraduodenal pancreatitis. The most common findings were spindled stromal cells, foamy cells, and granular debris. Although most often interpreted as negative for malignancy, the sampling of an area with abundant spindle cells or Brunner gland hyperplasia can mimic neoplasia. Careful attention to the clinical history and radiologic description can help to prevent over-diagnosis on FNA.

Anomalies, anatomic variants, and sources of diagnostic pitfalls in pancreatic imaging

In this review, a brief discussion of the important events of pancreatic embryology is followed by presentation of congenital anomalies and normal variants. For each variant, the appearance at different radiologic modalities including computed tomography, magnetic resonance (MR) imaging, endoscopic retrograde cholangiopancreatography, MR cholangiopancreatography, and fluoroscopy will be demonstrated.

Pancreatic imaging mimics: part 1, imaging mimics of pancreatic adenocarcinoma

OBJECTIVE

The purpose of this article is to describe the imaging features of diseases that may closely simulate pancreatic adenocarcinoma, either radiologically or pathologically.

CONCLUSION

Neoplastic and inflammatory diseases that can closely simulate pancreatic adenocarcinoma include neuroendocrine tumor, metastasis to the pancreas, lymphoma, groove pancreatitis, autoimmune pancreatitis, and focal chronic pancreatitis. Atypical imaging findings that should suggest diagnoses other than adenocarcinoma include the absence of significant duct dilatation, incidental detection, hypervascularity, large size (> 5 cm), IV tumor thrombus, and intralesional ducts or cysts.

Cystic dystrophy of the duodenal wall is not always associated with chronic pancreatitis

Cystic dystrophy of the duodenal wall is a rare form of the disease which was described in 1970 by French authors who reported the presence of focal pancreatic disease localized in an area comprising the C-loop of the duodenum and the head of the pancreas. German authors have defined this area as a “groove”. We report our recent experience on cystic dystrophy of the paraduodenal space and systematically review the data in the literature regarding the alterations of this space. A MEDLINE search of papers published between 1966 and 2010 was carried out and 59 papers were considered for the present study; there were 19 cohort studies and 40 case reports. The majority of patients having groove pancreatitis were middle aged. Mean age was significantly higher in patients having groove carcinoma. The diagnosis of cystic dystrophy of the duodenal wall can now be assessed by multidetector computer tomography, magnetic resonance imaging and endoscopic ultrasonography. These latter two techniques may also add more information on the involvement of the remaining pancreatic gland not involved by the duodenal malformation and they may help in differentiating “groove pancreatitis” from “groove adenocarcinoma”. In conclusion, chronic pancreatitis involving the entire pancreatic gland was present in half of the patients with cystic dystrophy of the duodenal wall and, in the majority of them, the pancreatitis had calcifications.

Pancreatoduodenal junction: review of anatomy and pathologic conditions

INTRODUCTION

The pancreatoduodenal junction is a small anatomic area where pathologic processes involving the distal bile duct, duodenum, pancreatic head, ampulla de Vater, and retroperitoneum converge. Differential diagnosis includes a spectrum of entities that ranges from anatomical variants to malignancies.

PURPOSE

The aim of this paper was to review the anatomy and different pathologic conditions, whether tumoral, inflammatory, or congenital in origin, in this specific area that involves the pancreatic head, duodenum, duodenal ampulla, distal pancreatobiliary tract junction, and retroperitoneum.

METHODS

Computed tomography (CT) and magnetic resonance (MR) help us to identify specific radiologic signs that allow to divide the pancreatic-duodenal junction abnormalities into three cathegories: (1) normal variants and congenital anomalies (pancreas divisum, santorinicele, annular pancreas,duodenal duplication cyst, choledocal cyst,...); (2) acquired non-tumoral: traumatic, iatrogenic, inflammatory (duodenal hematoma, duodenal iatrogenic perforation, groove pancreatitis, gastroduodenal artery pseudoaneurysm,...); (3) tumoral (pancreatic head adenocarcinoma, periampullary tumors, neuroendocrine pancreatic tumors, duodenal adenocarcinoma,...). The images illustrate morphologic aspects of these entities.

RESULTS AND CONCLUSIONS

CT and MR are the most appropiate imaging modalities to evaluate pancreatoduodenal junction. Knowing the imaging features is crucial to reach the right diagnosis and treatment of the different entities that involve this anatomic area.

Characteristic clinical and pathologic features for preoperative diagnosed groove pancreatitis

Purpose

Groove pancreatitis is a rare specific form of chronic pancreatitis that extends into the anatomical area between the pancreatic head, the duodenum, and the common bile duct, which are referred to as the groove areas. We present the diagnostic modalities, pathological features and clinical outcomes of a series of symptomatic patients with groove pancreatitis who underwent pancreaticoduodenectomy.

Methods

Six patients undergoing pancreaticoduodenectomy between May 2006 and May 2009 due to a clinical diagnosis of symptomatic groove pancreatitis were retrospectively included in the study.

Results

Five cases were male and one case was female, with a median age at diagnosis of 50 years. Their chief complaints were abdominal pain and vomiting. Abdominal computed tomography, endoscopic ultrasound and endoscopic retrograde cholangiopancreatography were performed. Preoperative diagnosis of all patients was groove pancreatitis. Histological finding was compatible with clinically diagnosed groove pancreatitis in five patients and the pathologic diagnosis of the remaining patient was adenocarcinoma of distal common bile duct. Following pancreaticoduodenectomy, four living patients experienced significant pain alleviation.

Conclusion

The diagnostic imaging modalities of choice for groove pancreatitis are computed tomography and endoscopic ultrasonography. If symptomatic groove pancreatitis is suspected, careful follow-up of patients is necessary and pancreaticoduodenectomy seems to be a reasonable treatment option.

Sonographic findings in groove pancreatitis

Groove pancreatitis is a rare form of chronic pancreatitis involving the anatomic plane between the pancreatic head and duodenum. The radiographic diagnosis remains challenging, and most patients undergo exploratory laparotomy on suspicion of a periampullary malignancy. The appearance of groove pancreatitis on transabdominal and intraoperative sonography has rarely been reported in the literature. The sonographic findings in our 2 patients included a hypoechoic thin area between the pancreatic head and duodenum, a hyperechoic and thickened wall of the adjacent duodenum, and a heterogeneous or hyperechoic dorsocranial part of the pancreatic head.

Groove pancreatitis: A Case Report and Review of the Literature

Groove pancreatitis is a rare form of segmental chronic pancreatitis. It involves the anatomic space between the head of the pancreas, the duodenum and the common bile duct. It was first described in the early 1970s, but it remains largely unfamiliar to most physicians. Radiological diagnosis can be challenging, as it is often difficult to differentiate it from other entities. The differential diagnosis from pancreatic head carcinoma may be difficult and recognition of subtle differences between these two entities is extremely important as the management differs significantly. Groove pancreatitis can be managed by conservative medical treatment, and surgery is reserved only for patients with persistent and severe clinical symptoms. We present a case of a 27 year-old male with groove pancreatitis and discuss the Magnetic Resonance Imaging (MRI) appearance of this entity as well as the differential diagnosis.