A rare case of groove pancreatitis from radiologic perspective

1. A RARE CASE OF GROOVE
PANCREATITIS-FROM
RADIOLOGIC PERSPECTIVE
E-poster Presented by
Dr Prasun Das, Junior Resident, department of radiology, NRSMCH

2. INTRODUCTION
• Groove pancreatitis (GP) is an under-recognized form of chronic pancreatitis (CP)
that involves the space between the pancreatic head, the duodenum, and the
common bile duct (CBD).
• Stolte et al[1]coined the term “groove pancreatitis”.
• traditionally classified into two forms: pure & segmental
• most frequently reported in young men with a history of alcohol abuse.
• In the pure form, in most cases the parenchyma and main pancreatic duct (MPD) are
not involved while in the “segmental” form, the scarring tissue affects the dorso-
cranial portion of the pancreatic head involving the MPD with a CP in addition to
groove involvement

3. AIM
• to highlight the different computed tomography (CT) features of GP in order to
make this entity more familiar to the radiologist.
• To aid in making a correct pre-operative imaging diagnosis and reduce further
diagnostic work-up such as invasive biopsy, thereby limiting the overall patient risk,
delayed diagnosis and apprehension.

4. METHOD
• STUDY DESIGN: a rare case report
• Method of data collection : Ultrasonography followed by computed tomography of
whole abdomen; after taking relevant clinical data
• Study tools: Logic p9 GE ultrasound machine
16 slice MDCT machine(GE BRIVO CT385)

5. CASE PRESENTATION
• A 36 yr old male patient was sent to radiology department from general surgery In-
patient Department for radiological evaluation . Patient gave clinical history of 3
months of epigastric pain with postprandial vomiting. He has addiction of drinking
for 10 yrs. He has reported that 5 kg weight loss happened in 3 yrs.
• The blood reports done in NRSMCH shows increased lipase and amylase level.
• Suspecting as malignancy,the surgery residents ordered serum CA 125 and CEA
level,which found to be in normal range.

6. On Ultrasound,we found a 3.2*3.3 cm
isoechoic mild heterogenous ill
defined area in pancreatic head
region.This area is close to 2nd part of
duodenum and appears to encircle
the CBD without any narrowing or
dialation.

7. There is no narrowing/dialation in CBD and portal vein at porta hepatis region. The
IHBRs are not dialated.Body and tail of pancreas are normal in echotexture.MPD is not
dilated(max diameter- 0.24cm).

8. COMPUTED TOMOGRAPHIC FINDINGS
On NCCT,the lesion appears to be isodense surrounding pancreatic parenchyma.Proximal gut
loops are not dialated.No intraperitoneal collection noted in HRPM.Loss of fat plain noted
between duodenum and pancreas.

9. On oral contrast enhanced CT,we found the oral contrast passes the distal part of
duodenum traversing the lesion,with visible narrowing of 2nd part duodenum due to the
lesion.The lesion appears to be sheet like encircling C loop.No collection is seen also in
pelvis.

10. On contrast enhanced CT, the lesion appears as hypodense compared to surrounding
contrast enhanced Pancreatic parenchyma. We can also do rt decubitus film to better
visualize the pancreatico duodenal groove.
There is no peripancreatic inflammatory changes noted.

11. MOST PROBABLE DIAGNOSIS
• GROOVE PANCREATITIS
• Other differential: Pancreatic adenocarcinoma in head region
• Very difficult to differentiate it from segmental form of GP.
• duodenal carcinoma, ampullary carcinomas, duodenal gastro intestinal stromal
tumor (GIST) or duodenal neuro-endocrine tumor (NET), conventional acute
edematous pancreatitis involving the groove

12. FURTHER INVESTIGATIONS TO BE
RECOMMENDED
• 1. DYNAMIC CT: delayed enhancement of fibrotic part of GP
• 2.MRI & MRCP
• ENDOSCOPIC ULTRASOUND
• ENDOSCOPIC FNAC
• MOST DEFINITE DIAGNOSIS BY HISTOPATHOLOGY

13. DISCUSSION
• The pancreatic-duodenal groove is a “theoretic” space between the pancreatic head
and the duodenal wall. A number of small arteries, veins and lymphatic pass
through this space. The most important vessel visible also or arterial phase of
contrast enhanced imaging studies is the pancreatic-duodenal artery (PDA) that
represent an important anatomical landmark[2]
• Each process arising medially respect to the PDA have a pancreatic origin. While
each process arising laterally respect to the PDA have a duodenal or pancreatic-
duodenal groove origin
• many important anatomical structures are present in the pancreatic-duodenal
groove space such as CBD, main and accessory pancreatic ducts, major and minor
papilla. This anatomical complexity account for many of the clinical and imaging
features of GP as well as for the differential diagnosis of this rare entity

14. • Cystic dystrophy and heterotopic pancreas (CDHP) are a predisposing anatomical
factor of CP, duodenal obstruction and obstructive jaundice, due to the presence of
pancreatic tissue at the duodenal wall, reflecting the incomplete involution of the
dorsal pancreas at this region.
• Chronic alcohol intake causes a decrease in bicarbonate secretion which increases
viscosity and consequent stagnation of pancreatic secretion in pancreatic ducts; it
follows an increase in pressure inside the Santorini duct with the release of the
secretion in the groove that promotes the formation of pseudocysts.
• Segmental form--the necrosis-fibrosis sequence
• Coronal reformatted images of a contrast enhanced CT of the medial duodenal wall
reveals better large thickening; small cysts or even a multilocular cystic mass are
often seen within the duodenal thickened wall or in the pancreatic-duodenal groove
itself
• The segmental form of GP exhibits a focal hypodense lesion in the pancreatic head
in close proximity to the duodenal wall. The MPD may exhibit mild upstream
dilatation in the pancreatic body and tail, while in the pure form of the disease the
pancreas appears normal[3]

15. • on MRI imaging, The mass is hypointense to pancreatic parenchyma on T1-weighted images,
and according to the time of disease onset can be hypo-, iso- or slightly hyperintense on T2-
weighted images [4]
• Appropriate interpretation of the T2 sequences is useful to infer the degree of disease
activity because of the signal changes from hyperintense, in the initial phases, to iso-
hypointense in the advanced phases
• the variations registered being due to the progressive accumulation of fibrous connective
tissues. In other terms, the subacute form of GP shows higher signal on T2-weighted images
due to edema while chronic form of the disease has a lower T2 signal due to fibrosis.
• Cystic degeneration within the duodenal wall is a specific sign of GP
• MRCP may show dilatation of the MPD in the form of segmental GP, while it may appear
normal in the pure form.
• EUS detect thickening and stenosis of the second duodenal part with intramural cysts
• endoscopy-guided FNA biopsy presents a great variability depending on the area sampled.
If the sampled area has a plentiful hyperplasia localized to Brunner's glands, it can
immediately be hypothesized that it corresponds to a neoplasm. Similarly, if any fibrotic area
is discovered with the use of EUS, a neoplasm cannot be ruled out, as a desmoplastic
reaction, mimicking an abnormal inflammatory alteration, is frequently associated with an
adenocarcinoma[5].

16. CONCLUSION
• The recognition of imaging findings such as cystic changes of the pancreatic groove and
duodenal wall thickening at CT and MRI and MRCP is important to suggest the diagnosis of
groove pancreatitis.
• Unfortunately, the differentiation of GP only on the basis of imaging characteristics, clinical
presentation and even with the aid of biological markers is very difficult, so that the patients
often undergo pancreaticoduodenectomy (Whipple procedure) precisely because can be
hard to completely exclude a neoplasm.
• However, knowledge of the all the GP radiological features may address the radiologist
towards the correct diagnosis exactly for the purpose of eliminating avoidable surgical
interventions. In those cases where the imaging features are highly characteristic and the
radiologist is able to strongly suggest the diagnosis on presentation, major surgery can
potentially be avoided.
•

17. TAKE HOME POINTS
• Groove pancreatitis (GP) is a rare variety of chronic pancreatitis.
• a long history of alcohol abuse in middle-aged men is thought to be the strongest
association
• tumor markers (CEA and CA 19-9) in GP are always within normal limits
• Most definite Histopathology- dilated ducts and pseudocystic changes in the
duodenal wall
• CT- The pure form may appear either as inflammatory changes with ill-defined fat
stranding of the groove; or as a frank hypodense soft tissue lesion that is centered
at the groove and often has a “sheetlike” curvilinear crescentic shape that is best
appreciated on coronal reformatted image

18. REFERENCES
• 1. Stolte M, Weiss W, Volkholz H, et al. A special form of segmental pancreatitis: groove
pancreatitis. Hepatogastroenterology 1982;29:198-208.
• 2. Raman SP, Salaria SN, Hruban RH, et al. Groove pancreatitis: Spectrum of imaging findings
and radiology-pathology correlation. AJR Am J Roentgenol 2013;201:W29-39
• 3. Ray S, Ghatak S, Misra D, et al. Groove Pancreatitis: Report of Three Cases with Brief
Review of Literature. Indian J Surg 2017;79:344-8.
• 4. Blasbalg R, Baroni RH, Costa DN, et al. MRI features of groove pancreatitis. AJR Am J
Roentgenol 2007;189:73-80.
• 5. Brosens LA, Leguit RJ, Vleggaar FP, et al. EUS-guided FNA cytology diagnosis of
paraduodenal pancreatitis (groove pancreatitis) with numerous giant cells: conservative
management allowed by cytological and radiological correlation. Cytopathology
2015;26:122-5