Meandering main pancreatic duct as a relevant factor to the onset of idiopathic recurrent acute pancreatitis

Case of usefulness of drill dilator for pancreatic stone disease in a reverse-Z type main pancreatic duct

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Pancreatic congenital anomalies and their features on CT and MR imaging: a pictorial review

OBJECTIVE

To review the congenital anomalies of the pancreas with their main clinical manifestations and key imaging findings on CT and MRI.

BACKGROUND AND CLINICAL SIGNIFICANCE

Anomalies of pancreatic development are frequent and generally asymptomatic, but can mimic and predispose individuals to pancreatic or peripancreatic pathologies, such as pancreatitis or malignancy. Their correct diagnosis may help avoid unnecessary further investigations and procedures, or establish adequate treatment when they manifest clinically. Differentiating pancreatic congenital anomalies from their main radiological mimics constitutes a challenge for the radiologist and requires familiarity with key imaging findings.

CONCLUSION

The imaging findings of CT and MRI are essential for the correct diagnosis of congenital pancreatic anomalies.

Correlation between Pancreatic Duct Variation and Related Diseases: An Effective Method Observing the Dual-Energy CT with Low-keV Monoenergetic Images

PURPOSE

Pancreatic duct variation can affect the secretory function of the pancreas. We aimed to explore the pancreatic duct variation, observed using low-keV monoenergetic images [MEI (+)] of dual-energy CT (DECT), and its relationship with related diseases. We further sought to compare pancreatic duct imaging using low-keV MEI (+) of DECT and magnetic resonance cholangiopancreatography (MRCP).

MATERIALS AND METHODS

The DECT and MRCP images of 854 patients were evaluated retrospectively. The 808 patients' pancreatic duct types were classified according to the anatomy and the opening of the pancreatic ducts, and the correlation with related diseases was analyzed. The DECT and MRCP images of 852 patients were graded according to the sharpness of the pancreatic ducts for evaluation.

RESULTS

A higher prevalence of acute pancreatitis (AP), chronic pancreatitis (CP), and duodenal papillary carcinoma (DPC) was observed in the variant group. Of the 27 AP cases in the variant group, 9 patients (33.3%) were Type 3c. Additionally, Type 4a was significantly correlated with AP and CP (p < 0.05). Low-keV MEI (+) of DECT outperformed the MRCP images in the sharpness of the pancreatic ducts in 852 patients.

CONCLUSIONS

Pancreatic duct variation is associated with AP, CP, and DPC. Low-keV MEI (+) DECT is an effective method to observe the pancreatic duct system.

Anatomical pancreatic variants in intraductal papillary mucinous neoplasm patients: a cross-sectional study

Background

No previous studies have examined the possible relationship between intraductal papillary mucinous neoplasm (IPMN) and the developmental ductal variations of the pancreas, such as an ansa pancreatica and a meandering main pancreatic duct (MMPD).

Methods

This retrospective cross-sectional study enrolled 214 patients, 108 with IPMN disease and 106 subjects from a community at the tertiary care unit. The main pancreatic duct (MPD) was evaluated in the head of the pancreas by its course, which were non-MMPD: descending, vertical, and sigmoid, or MMPD including loop types, reverse-Z subtypes, and an N-shape, which was identified for the first time in this study. IPMN patients were also evaluated for worrisome features (WF) or high-risk stigmata (HRS), and the extent of IPMN cysts.

Results

Among IPMN patients, 18.4% had MMPD, which we observed in only 3.0% of the control group (P < 0.001). Patients with MMPD were more likely to belong to the IPMN group compared with non-MMPD patients [odds ratio (OR) 6.4, 95% confidence interval (CI) 2.2–24.9]. Compared with a descending shape MPD, IPMN patients with an N-shaped MPD were more likely to have a cystic mural nodule (OR 5.9, 95% CI 1.02–36.0). The presence of ansa pancreatica associated with more extent IPMN disease (OR 12.8, 95% CI 2.6–127.7).

Conclusions

IPMN patients exhibited an MMPD more often than control patients. Ansa pancreatica associated with multiple cysts. Furthermore, an N-shape in IPMN patients associated with cystic mural nodules, suggesting that this shape serves as a risk factor for more severe IPMN.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02465-w.

Three-Dimensional Radiomics Features of Magnetic Resonance T2-Weighted Imaging Combined With Clinical Characteristics to Predict the Recurrence of Acute Pancreatitis

Objective

To explore the diagnostic value of radiomics model based on magnetic resonance T2-weighted imaging for predicting the recurrence of acute pancreatitis.

Methods

We retrospectively collected 190 patients with acute pancreatitis (AP), including 122 patients with initial acute pancreatitis (IAP) and 68 patients with recurrent acute pancreatitis (RAP). At the same time, the clinical characteristics of the two groups were collected. They were randomly divided into training group and validation group in the ratio of 7:3. One hundred thirty-four cases in the training group, including 86 cases of IAP and 48 cases of RAP. There were 56 cases in the validation group, including 36 cases of IAP and 20 cases of RAP. Least absolute shrinkage and selection operator (LASSO) were used for feature screening. Logistic regression was used to establish the radiomics model, clinical model and combined model for predicting AP recurrence. The predictive ability of the three models was evaluated by the area under the curve (AUC). The recurrence risk in patients with AP was assessed using the nomogram.

Results

The AUCs of radiomics model in training group and validation group were 0.804 and 0.788, respectively. The AUCs of the combined model in the training group and the validation group were 0.833 and 0.799, respectively. The AUCs of the clinical model in training group and validation group were 0.677 and 0.572, respectively. The sensitivities of the radiomics model, combined model, and clinical model were 0.646, 0.691, and 0.765, respectively. The specificities of the radiomics model, combined model, and clinical model were 0.791, 0.828, and 0.590, respectively. There was no significant difference in AUC between the radiomics model and the combined model for predicting RAP (p = 0.067). The AUCs of the radiomics model and combined model were greater than those of the clinical model (p = 0.008 and p = 0.007, respectively).

Conclusions

Radiomics features based on magnetic resonance T2WI could be used as biomarkers to predict the recurrence of AP, and radiomics model and combined model can provide new directions for predicting recurrence of acute pancreatitis.

Meandering Main Pancreatic Duct in Association with Choledochal Cysts and Acute Pancreatitis in Pediatrics

Meandering main pancreatic duct (MMPD) is an uncommon anomaly of the main pancreatic duct characterized by an abnormal curvature at the pancreatic head region. This variant can be diagnosed on imaging, particularly magnetic resonance cholangiopancreatography (MRCP). Although its clinical significance remains debatable, recent research suggests an association with recurrent acute pancreatitis. To our knowledge, no pediatric cases of acute or recurrent acute pancreatitis have been attributed to the presence of MMPD. In this article, we report on two patients. The first case is of a 15-year-old girl with MMPD discovered on investigation of idiopathic acute pancreatitis. The second case is of a 5-year-old boy who presented with his second episode of acute pancreatitis. In this patient, MRCP imaging revealed MMPD and type IVA choledochal cyst. With appropriate care, both patients experienced clinical improvement with resolution of abdominal pain. This article highlights MMPD as a distinct entity that should be considered in pediatric patients with recurrent attacks of acute pancreatitis. This report also describes the first association of MMPD with choledochal cysts. [Pediatr Ann. 2019;48(10):e412-e416.].

Association between chronic asymptomatic pancreatic hyperenzymemia and pancreatic ductal anomalies: a magnetic resonance cholangiopancreatography study

PURPOSE

Elucidating the association between pancreatic ductal anomalies and chronic asymptomatic pancreatic hyperenzymemia using magnetic resonance cholangiopancreatography.

METHODS

We conducted a single-center, retrospective, case-control study. The healthy community group comprised 554 subjects who participated in a paid, whole-body health checkup program. The patient group comprised 14 subjects with idiopathic pancreatic hyperamylasemia or hyperlipasemia. All subjects underwent magnetic resonance cholangiopancreatography. The clinical features and incidence rates of pancreatic ductal anomalies were then compared between the groups.

RESULTS

Compared to the healthy community group, the patient group was significantly more likely to be ≥ age 65 (71.4% of patient group vs. 22.1% of healthy community group), have a history of diabetes mellitus (21.4% vs. 5.4%) or hypertension (35.7% vs. 11.4%), and to have pancreas divisum (21.4% vs. 2.7%), meandering main pancreatic duct (21.4% vs. 4.1%), Wirsungocele (14.3% vs. 1.1%), or dilated main pancreatic duct (14.3% vs. 2.3%). Multivariate analysis found that age ≥ 65 (odds ratio 8.76), presence of pancreas divisum (odds ratio 13.2), meandering main pancreatic duct (odds ratio 8.95), and Wirsungocele (odds ratio 17.6) were independent factors significantly associated with chronic asymptomatic pancreatic hyperenzymemia.

CONCLUSIONS

Pancreas divisum, meandering main pancreatic duct, and Wirsungocele were independently associated with chronic asymptomatic pancreatic hyperenzymemia.

Pancreas divisum: a reemerging risk factor for pancreatic diseases

Pancreas divisum (PD) is the most common developmental anatomic variant of pancreatic duct. The attention towards the PD has grown significantly since there are reports that this condition may cause acute relapsing pancreatitis, chronic pancreatitis and chronic abdominal pain syndrome. Furthermore, over the years, there have been multiple reports of PD associated with different types of tumors. There is evidence that PD can be associated with pancreatic tumors (up to 12.5% of cases). The golden standard for diagnosing PD is endoscopic retrograde cholangiopancreatography, but since it is an invasive procedure magnetic resonance cholangiopancreatography with secretin is a good alternative. In case the patient is symptomatic, endoscopic or surgical treatment should be performed. This review describes the key points of the pathophysiology, diagnostic modalities, risks of pancreatitis and tumors, as well as treatment options of PD.

Development of pancreatic cancer is predictable well in advance using contrast-enhanced CT: a case-cohort study

OBJECTIVES

To investigate the radiological findings prognostic for the development of pancreatic adenocarcinoma in a cohort of patients with hepatocellular carcinoma, using multiphasic computed tomography (CT).

METHODS

A case-cohort study performed in a single university hospital. A database of patients who received hepatocellular carcinoma (HCC) treatment and trimonthly follow-up with four-phase dynamic CT was used (n = 1848). The cohort group was randomly extracted from the database (n = 103). The case group comprised nine patients from the database who developed pancreatic adenocarcinoma. The radiological findings were assessed during follow-up (average, 32 months).

RESULTS

The incidence of pancreatic mass, inhomogeneous parenchyma, loss of fatty marbling and main pancreatic duct dilatation gradually increased from 4 to 13 months before the diagnosis of pancreatic adenocarcinoma. There was a significantly higher incidence of pancreatic mass, inhomogeneous parenchyma and loss of fatty marbling on CT at baseline (average, 34 months before diagnosis) in the case group compared with the cohort group (P values < 0.01) and those findings at baseline were revealed as prognostic factors for pancreatic carcinogenesis, respectively (log-rank test, P values < 0.001).

CONCLUSIONS

Several radiological findings observed on multiphasic CT can assist in predicting pancreatic carcinogenesis well in advance.

KEY POINTS

• Pancreatic findings in multiphasic CT help predict development of pancreatic adenocarcinoma. • Key findings are mass, inhomogeneous parenchyma and loss of fatty marbling. • Those findings were observed 34 months before confirmed diagnosis of adenocarcinoma. • Those findings were prognostic factors for pancreatic carcinogenesis.

Anatomic variations of the pancreatic duct and their relevance with the Cambridge classification system: MRCP findings of 1158 consecutive patients

BACKGROUND

The study was conducted to evaluate the frequencies of the anatomic variations and the gender distributions of these variations of the pancreatic duct and their relevance with the Cambridge classification system as morphological sign of chronic pancreatitis using magnetic resonance cholangiopancreatography (MRCP).

PATIENTS AND METHODS

We retrospectively reviewed 1312 consecutive patients who referred to our department for MRCP between January 2013 and August 2015. We excluded 154 patients from the study because of less than optimal results due to imaging limitations or a history of surgery on pancreas. Finally a total of 1158 patients were included in the study.

RESULTS

Among the 1158 patients included in the study, 54 (4.6%) patients showed pancreas divisum, 13 patients (1.2%) were defined as ansa pancreatica. When we evaluated the course of the pancreatic duct, we found the prevalence 62.5% for descending, 30% for sigmoid, 5.5% for vertical and 2% for loop. The most commonly observed pancreatic duct configuration was Type 3 in 528 patients (45.6%) where 521 patients (45%) had Type 1 configuration.

CONCLUSIONS

Vertical course (p = 0.004) and Type 2 (p = 0.03) configuration of pancreatic duct were more frequent in females than males. There were no statistically significant differences between the gender for the other pancreatic duct variations such as pancreas divisium, ansa pancreatica and course types other than vertical course (p > 0.05 for all). Variants of pancreas divisum and normal pancreatic duct variants were not associated with morphologic findings of chronic pancreatitis by using the Cambridge classification system. The ansa pancreatica is a rare type of anatomical variation of the pancreatic duct, which might be considered as a predisposing factor to the onset of idiopathic pancreatitis.

Ansa pancreatica as a predisposing factor for recurrent acute pancreatitis

AIM

To determine the non-biased prevalence and clinical significance of ansa pancreatica in patients with acute pancreatitis using magnetic resonance imaging (MRI).

METHODS

Our institutional review board approved this cross-sectional study, which consisted of a community-based cohort of 587 consecutive participants in a whole-body health-check program, and 73 subjects with episode of acute pancreatitis (55 patients with a single episode of acute pancreatitis, and 18 patients with recurrent acute pancreatitis). All of the subjects underwent abdominal MRI including magnetic resonance cholangiopancreatography, medical examinations, and blood tests. Two board-certified, diagnostic, abdominal radiologists evaluated the images, and ansa pancreatica was diagnosed based on its characteristic anatomy on MRI.

RESULTS

Compared with the community group [5/587 (0.85%)], patients with recurrent acute pancreatitis had a significantly higher frequency of ansa pancreatica [2/18 (11.1%)] (P = 0.016; OR = 14.3; 95%CI: 1.27-96.1), but not compared with patients with single-episode acute pancreatitis [1/55 (1.8%)] (P = 0.42; OR = 2.1; 95%CI: 0.44-19.7). Multiple logistic regression analysis using age, alcohol intake, presence of ansa pancreatica, and presence of autoimmune disease as independent covariates, revealed a significant relationship between the presence of ansa pancreatica and recurrent acute pancreatitis. The presence of autoimmune disease was also significantly associated with the onset of recurrent acute pancreatitis. On the other hand, neither age nor alcohol intake were significantly related to the onset of recurrent acute pancreatitis.

CONCLUSION

The present study is the first to provide robust evidence that the presence of ansa pancreatica is significantly associated with recurrent acute pancreatitis.

A distinctive myoepithelial hamartoma of the pancreas histologically confirmed in the mother of a previously reported patient

We encountered a 62-year-old female patient with a distinctive pancreatic myoepithelial hamartoma characterized by dilated loops formed by pancreatic branch ducts. The patient, who experienced recurrent acute pancreatitis caused by pancreatic juice stasis, underwent subtotal stomach-preserving pancreatoduodenectomy, achieving remission of pancreatitis. Computed tomography (CT) and magnetic resonance cholangiopancreatography (MRCP) demonstrated a honeycomb appearance of the pancreatic head, consisting largely of loop-forming dilated pancreatic branch ducts. Radiography of resected specimens demonstrated a tortuous main pancreatic duct that narrowed in the head, but communicated with the pancreatic branch ducts forming intricate loops within the lesion. Histologic examination showed dilated pancreatic ducts embedded in thick layers of smooth muscle, leading to a diagnosis of myoepithelial hamartoma. Her son shared a similar clinical course, radiologic findings, and histopathologic findings with his mother. MRCP demonstrated a honeycomb appearance of the pancreatic head in her daughter, who complained of persistent diarrhea. To our knowledge, this is the first English-language reports of such a myoepithelial hamartoma of the pancreas showing familial occurrence.

The angle of pancreaticobiliary junction correlates with acute pancreatitis: a magnetic resonance cholangiopancreatography study

OBJECTIVE

To study the correlation between the angle of the pancreaticobiliary junction (APJ) and the prevalence of acute pancreatitis using magnetic resonance cholangiopancreatography (MRCP).

MATERIALS AND METHODS

From February 2014 to October 2014, thirty two subjects with normal pancreas (group A) and 40 patients with acute pancreatitis (group B) who underwent MRCP were enrolled into our study. The type of biliary duct and main pancreatic duct joining the duodenal wall was reviewed and divided into V, B-P and P-B type. The V type is the pancreatic duct and biliary duct joining the duodenal wall without a common channel; the B-P type is the biliary duct draining into the pancreatic duct and forming a common channel; and the P-B type is the pancreatic duct draining into the biliary duct and forming a common channel. APJ was measured on MRCP. The correlation between the APJ and the prevalence of acute pancreatitis was analyzed.

RESULTS

The APJ in group A was smaller than in group B (51.45°±13.51° vs. 65.76°±15.61°, P<0.05). According to the type of biliary duct and main pancreatic duct joining the duodenal wall, the prevalence of acute pancreatitis in the V type and in the B-P type was higher than in the P-B type (12/17 vs. 10/29, or 18/26 vs. 10/29, respectively, all P<0.05), whereas there were no significant difference for the prevalence of acute pancreatitis between the V type and B-P type (P>0.05). The APJ were 59.32°±20.04°, 60.22°±11.06°, 57.13°±17.27°, respectively in V type, B-P type and P-B type joining of main pancreatic duct (P>0.05).

CONCLUSIONS

A larger APJ is related to a higher prevalence of acute pancreatitis.

Santorinicele without pancreas divisum pathophysiology: initial clinical and radiographic investigations

BACKGROUND

Only one case of santorinicele without pancreas divisum pathophysiology (SWOPP) was previously reported. The purpose of the study was to determine the gross prevalence of SWOPP and santorinicele with pancreas divisum (SWPD) in community and patient populations, and investigate their clinical and radiographic features.

METHODS

This cross-sectional study was performed at a tertiary referral centre. The Patient group comprised 2035 consecutive patients enrolled in the study who underwent magnetic resonance cholangiopancreatography (MRCP) studies. The Community group comprised 2905 consecutive subjects who participated in our whole-body medical check-up program that routinely includes MRCP studies. SWOPP was diagnosed when a saccular dilatation of the terminal portion of the dorsal pancreatic duct was observed unaccompanied by pancreas divisum or dominant dorsal duct. The prevalence of SWOPP and SWPD, and the clinical and radiological features were assessed in each group.

RESULTS

Five cases of SWOPP were found in the Patient group (age range, 67-85 years; mean age, 73.6 years) (5/2035 = 0.25%; 95% confidence interval, 0.07-0.57); there were no cases of SWOPP in the Community group (0/2905 = 0.00%; 95% confidence interval, 0.00-0.10) (P = 0.01). Previous history of pancreatitis (4/5) and chronic pancreatitis (3/5) was more common in patients with SWOPP than in other subjects in the Patient or Community groups (both P < 0.05). Two cases of SWOPP were accompanied by reverse-Z type meandering main pancreatic duct. Six cases of SWPD were found. These cases were asymptomatic in 4/6, had a larger santorinicele (6.9 mm) than SWOPP patients (4.5 mm; P = 0.02), and were not associated with pancreatitis (0/6).

CONCLUSIONS

The second to sixth reported cases of SWOPP were presented. SWOPP is a relatively rare condition found mostly in patients suffering pancreatitis, especially chronic pancreatitis, and may be an acquired condition. Santorinicele is not always accompanied by pancreas divisum.

False pancreas divisum: a complication of post-endoscopic retrograde pancreatography pancreatitis

Pancreas divisum (PD) and meandering main pancreatic duct (MMPD) are common developmental variants of the pancreatic ductal system. They always appear in the head of the pancreas and are associated with idiopathic pancreatitis. The condition of these variants is rarely reported to have changed after birth. We present a rare case of false PD that occurred with alteration of loop-type MMPD after endoscopic retrograde pancreatography (ERP) and brush cytology followed by post-procedural pancreatitis. A 76-year-old female underwent pre-surgical ERP and brush cytology for an incidentally detected, expanding branch-type intraductal papillary mucinous neoplasm in the body of pancreas. The guidewire was inserted along the main pancreatic duct (MPD) and had uncoiled the loop-shaped MPD into a linear shape; soon afterwards, the patient developed post-procedural acute pancreatitis. Follow-up magnetic resonance cholangiopancreatography study 1 month later revealed the morphology of PD with an absent ventral duct. We hypothesize that inflammatory synechia had occluded the uncoiled ventral duct. This single case provides evidence that pancreatic ductal anatomy is flexible in some situations.