Congenital Abnormalities Pancreas

Several systems are in use for classifying congenital pancreatic duct anomalies. A common scheme is to subdivide anomalies into migration and fusion. The most common is fusion failure between the dorsal and ventral pancreatic ducts (pancreas divisum). Migration variations include pancreatic rests, which are formed by incomplete migration of the prepancreatic anlage.As a result, pancreatic tissue remains in stomach wall, duodenum, and other structures.Likewise, failure of full rotation of the prepancreatic buds results in an annular. In some patients it is difficult to predict whether a detected congenital anomaly is indeed responsible for a particular clinical problem.
Agenesis
Complete agenesis of the pancreas is incompatible with life. Partial agenesis is rare,with either the ventral or dorsal segment failing to develop. This congenital anomaly is associated with polysplenia and intrathoracic anomalies. Agenesis of the dorsal segment results in only the head of the pancreas being present; CT and MR show this segment as an oval mass. Many of these patients also have diabetes mellitus, presumably because of islet cell agenesis, which normally are predominantly located in the body and tail of the pancreas. The uncinate process is either absent or hypoplastic in patients with intestinal nonrotation, presumably secondary to incomplete pancreatic primordial ventral bud rotation.
Pancreas Divisum Pancreatography and immunohistochemical staining of pancreatic polypeptide identify two types of dorsal and ventral duct fusion: (1) one-point fusion at the junction of main duct and accessory pancreatic duct, and (2) twopoint fusion not only at the primary duct junction site but also at a second site. Abnormal embryologic fusion (or lack of fusion) of the ventral and dorsal primordia causes pancreas divisum.
image
radiology images of Schematic configuration of dilated pancreatic ducts. A: Drainage is via the duct of Wirsung. The minor papilla drains only a small portion of the pancreas. B: Pancreas divisum. Most of the pancreas is drained via the duct of Santorini (S). Insertion of the common bile duct marks the major papilla and identifies the duct of Wirsung (W). C: The ducts of Santorini and Wirsung communicate freely but drain through their respective papillae.

Pancreas divisum is the most common congenital anomaly of the pancreas, with autopsy studies showing about a 6% prevalence. Some consider pancreas divisum to be an innocuous congenital variant, while others believe that it is associated with a higher prevalence of pancreatitis. The frequency of pancreas divisum in patients with pancreatitis is significantly higher than in a general population. If found in several family members, is this hereditary pancreatitis in a setting of familial pancreas divisum? Pancreatitis in this patient population often is focal and limited to a dorsal distribution. It is
often technically difficult in these patients to cannulate the dorsal pancreatic duct (duct of Santorini); nevertheless, some endoscopy centers have achieved a high success rate and have become referral centers for this procedure. Pancreas divisum does not appear to predispose to an anomalous pancreaticobiliary duct union.
Pancreas divisum is generally detected by pancreatography.At times CT identifies distinct ventral and dorsal pancreatic ducts. Occasionally CT suggests pancreas divisum by an indistinct mass in the head of the pancreas.
An MRCP detects about half the pancreas divisum anomalies. Secretin administration appears to aid in this detection. The prevalence of both acute relapsing pancreatitis and chronic pancreatitis appears to decrease following minor papilla sphincterotomy and resultant accessory duct decompression. At times stenting of the dorsal pancreatic duct relieves symptoms.
image
Pancreas divisum. A: Endoscopic retrograde cholangiopancreatography (ERCP) with contrast injection into the main papilla outlines only a short,narrow caliber duct of Wirsung.Parenchymal contrast is evident. B: Computed tomography (CT) identifies a dilated duct (arrow) not conforming to the usual course of the main pancreatic duct.
Annular Pancreas
In neonates an annular pancreas is associated with esophageal atresia, tracheoesophageal fistula, duodenal stenosis or atresia, and malrotation. Rare instances of an annular pancreas and pancreas divisum in the same patient have been reported. Symptoms of an annular pancreas not uncommonly manifest during adulthood, the most common findings being abdominal pain, gastric outlet obstruction, pancreatitis, and a pancreatic tumor.
image
Radiology images of Duodenal stricture (arrow), believed to be secondary to pancreatitis in an annular pancreas.

In the newborn, conventional radiography of complete obstruction by an annular pancreas shows a “double-bubble” sign with no bowel gas distally. Only in a minority of older individuals does a barium study suggest annular pancreas. CT and MRCP also underdiagnose this condition. At times ERP suggests the diagnosis, although in some patients confirmation is made only at surgery. Computed tomography and MR identify the second part of the duodenum being surrounded by pancreatic tissue; at times a pancreatic duct segment is identified in the annular portion. In some patients this circumferential duodenal narrowing is due mostly to fibrotic tissue. A cyst developing adjacent to the duodenum in a patient with an annular pancreas and repeated attacks of pancreatitis should suggest a (pseudo)cyst.
image
Radiology images of Annular pancreas. After oral and IV contrast CT shows the pancreas surrounding descending duodenum (arrow).
Ectopic Pancreas
Ectopic (heterotopic) pancreatic tissue is most often found in the gastric antrum and proximal duodenum, although it can be located anywhere in the gastrointestinal tract, including a Meckel’s diverticulum.
Inflammation does develop in ectopic pancreatic tissue (called cystic dystrophy of an ectopic pancreas by some authors). If chronic, fibrosis and bowel stenosis ensue. Acute pancreatitis and even a (pseudo)cyst have developed in an ectopic pancreas. Similarly, this tissue is not immune to tumor formation; a carcinoma originated in ectopic pancreatic tissue in the esophagus, and a papillary cystic neoplasm developed in ectopic pancreatic tissue in the omentum.
Aberrant Duct Insertion
During embryonic development a network of duct branches eventually fuses and forms a primary channel. Aberrant fusion leads to a number of duplication anomalies of the pancreatic ducts and results in one or more main duct. This congenital anomaly is often associated with an apparent tumor on CT imaging. The pancreatic duct can communicate with a duodenal duplication or even involve aberrant bile ducts and the patient presents with a periampullary  cystic tumor; CT and ERCP are helpful in defining the underlying anatomy and planning surgery.
Cysts
Congenital cysts of the pancreas are either true cysts or pseudocysts. Both are rare. They range from solitary to multiple. True cysts are lined by epithelium. These cysts in neonates tend to be large and their clinical differential diagnosis often includes renal, choledochal, mesenteric, ovarian, and gastrointestinal origin cysts. An increased prevalence of simple cysts is found in patients with polycystic kidney disease, tuberous sclerosis, and von Hippel- Lindau disease. Incidentally detected multiple pancreatic cysts, especially in a young patient without pancreatic disease, should suggest one
of these entities. Patients with von Hippel- Lindau disease are also prone to developing cystic pancreatic neoplasms. In fact, in an occasional patient pancreatic lesions are the only abdominal manifestation of von Hippel-Lindau
disease.
Computed tomography or MR confirms a cyst’s location and its relationship to pancreatic parenchyma; imaging tends not to differentiate among congenital cysts, a cystic neoplasm, and other cystic lesion. Precontrast CT of a lymphoepithelial cyst revealed a heterogeneous water-density tumor, with septa identified postcontrast; MRI showed a hypointense mass on T1- and a hyperintense mass on T2-weighted imaging, with septa identified on postgadolinium images. Endoscopic US confirmed the presence of septa and also detected fine hyperechoic structures within the cyst. A cystic neoplasm was suspected preoperatively.
Histiocytosis Langerhans cell histiocytosis is the current term for disorders previously known as histiocytosis X. This is a rare disorder, with pancreatic involvement being even rarer.

Artikel Terkait

Congenital Abnormalities Pancreas
4/ 5
Oleh

Berlangganan

Suka dengan artikel di atas? Silakan berlangganan gratis via email

This below all content of radiology information

Neuroradiology Musculoskeletal radiology MRI Musculoskeletal MRI Abnormal Mri Brain X-RAY differential diagnosis Head Neck Anatomy mnemonic CT Teleradiology Radiology News chest Radiology musculoskeletal salary pediatrics ultrasound ultrasound images job Brain tumour abdomen interventional radiology CT Abdomen with contrast DAMS Imaging Apk Android radiology ramblings residency c nature pediatric radiology random ramblings xray C T Radiology Top basics body imaging guide procedure web 2.0 Chest X Ray Interpretation Teleradiology Providers head and neck radiology video Fun b cancer chest radiology salary 1 CXR GenitoUrinary ORTHOPEDICS Sonographic Measurements Stroke Ultrasound Hepatitis dams md/ms coaching mammography radiology business tuberculosis BRAIN Clinicoradiological series FETUS GI radiology Gastrointestinal x ray Radiology 4 Radiology Conferences Radiology Images Telemedicine UPPER LIMPS Ultrasound in Emergencies dynamic MRI lifestyle radiology links renal case spine 3 tesla MRI Dams clinicoradiological series Entrepreneur Gastrointestinal Tract Images Literature Liver abscess ultrasound MD/MS coaching Radiology 40 Radiology Imaging Radiology Journal Radiology PDF Radiology mcqs Ultrasound Technique blog bone tumour cardiac CT career cerebral venous thrombosis chest xray d fracture gadolinium gastrointestinal genitourinary radiology hepatobiliary imaging lipoma medical blogs mri lower abdomen pelvis psychiatry radiation concern social networking technology training urogenital imaging weblog 3D CT Arachnoid cyst CT Cardiac Chest X Ray Diploma Guid Equipment Cost FDA Fibrous dysplasia Interventional Ultrasound Guiding Biopsi MDCT MR Pancreas MRI Vertebrae MRI Vertebrae lumbal MRI contrast MRS RTA Radiology Teaching resource TB Hip TECHNIQUE Tech Thorax X Ray Upper Ext aiims ankle sprain bowel cancer brain abscess case study computers and radiology contrast ependymoma epidermoid facebook guest post internet journal of radiology iphone kienbock disease liver liver segments ct locum tenens mri abdomen multislice CT pericallosal lipoma plain film teaching files private practice radiology humour shoulder arthrogram shoulder dislocation small bowel social media trigeminal neuralgia tuberous sclerosis venous x ray Vertebrae 3d printing 7 tesla MRI ACL reconstruction ACL tear ACLS AIIMS nov 2008 ALPSA lesion ANGIOGRAPHY ATFL B12 deficiency BLS BOLD Breast imaging Breast imaging Mammography CHF CT Paranasal CT Scanner Price CT angiography CT coronary angiography CT technology CV junction CXR teaching files Carcinoid Contrast Agent Creutzfeldt-Jakob Disease Dams MD/ms Dams grand rounds Diffusion weighted imaging Dysmenorrhea E E World Award 2011 EYE Embolization Imaging Entrepreneurship FMG India FMGE FNH Focal liver lesions ultrasound Focal nodular hyperplasia GBM GI Gall bladder Glioblastoma multiforme Glomus jugulare HEAD HEART HRCT HSG Head injury ICA dissection IRIA 2011 IUGR IVC filter Iliotibial Band Friction Syndrome Job Info Kidney Cancer LV thrombus Leptomeningeal cyst MAMOGRAPHY MCI Screening MD MPPG MR mammography MR urography MRA MRCP MRI Cervical MRI update MRI/PET MRV Mesenteric ischemia Middle East respiratory syndrome coronavirus (MERS-CoV) Motor neuron disease NECK Normal Liver US Oncology trial PDF Radiology PM and R Physician PNS Partial anomalous pulmonary venous drainage Persistent trigeminal artery Pg entrance Physiatrist Physiatry Physician Assistant Plastic Surgery Price MRI Machines 2017 Pulmonology Pulvinar sign Radiology Price List Radiology Today Radiology Updates Radiology grandrounds Radiology images of GI Tract Renal Ultrasound Retinal Surgery Rheumatology Ryles tube SKULL Seizure Sellar Masses Sleep Medicine Sports Medicine Subdural hematoma Surgery TBM TRIANGULAR FIBROCARTILAGE COMPLEX Trauma Surgery URI Ultrasound HIV Umbilical vein Update Article Upper Extremity X Ray Urology Usmle VHL Vascular Surgery Veteran Affairs X Ray Head about accessory bone acute cerebillitis acute pancreatitis aiims may 2011 aipg ankle ankle fracture apple articular cartilage aspergilloma atherosclerosis avulsion injury awards bankart lesion basilar artery thrombosis bilateral phaeochromocytoma biopsy bipolar bohler's angle bone tumours brachial plexus brain tb brainstem stroke branchial cyst breast cancer screening buford complex business today calcaneal fracture calcium scoring canned reports carcinoma esophagus carcinoma stomach cardiac ct/pet cardiac pacemaker cardiogen 82 cardiothoracic imaging catrotid artery dissection cavernoma cervical lymphnode levels chest radiographic score chest radiographs choledocolithiasis classification cloud computing cochlear implant colloid cyst communication in radiology compare case concha bullosa congenital brain anomalies congenital heart disease coronary CT coronary artery disease corpus callosum agenesis craniopharyngioma cryptococcal meningitis ct abdomen and pelvis cystic renal disease dams usmle dams visual treat deep brain stimulator dengue dengue hemorrhagic fever developmental dysplasia devices diagnostic imaging dialysis diffusion MR imaging diffusion tensor imaging diffusion tractography digital radiography distal facial neuroma dsa duplication gall bladder echinococcus echocardiography ectopic kidney elearning elevated diaphragm epilepsy esop facial neuroma fibular osteosarcoma functional mri gastrointenstinal tuberculosis germinoma gifts glioma google google plus gun shot injury haemangioblastoma health 2.0 healthcare consultancy hemangiblastoma hemophilia hippocampus hirayama disease hydatid cyst hypercoagulable hypoxic ischemic encephalopathy indian conferences inferior rectus anomaly infrared interior tomography interstitial lung disease intramedullary metastates intramedullary tuberculomas ipad ipad 2 jacoud's arthropathy kernohan's notch knee kohler's disease krukenberg tumour laceration leber's optic atrophy liver transplant lung contusion lymphatics macros marchifava bingami disease mastoiditis maxillary sinus mucocele medial malleolus ossicle medial tibial stress syndrome medical writting medicare medicolegal aspects of teleradiology migraine mortality motor area mri knee mri lumbal msk penang course mucinous cystadenoma multicentric Glioblastoma multiforme mycotic pseudoaneurysm of superficial temporal artery nephrogenic systemic fibrosis nephrology neurosurgery meets nonradiologist oesophagus olecranon spur online medical games open access opercular syndrome opinion orbit os odontoideum os radiale externum osirix osteochondritis osteochondroma osteoid osteoma outsourcing radiology ovarian tumour parameniscal cyst paranasal sinuses parotid vascular mass patellar sleeve avulsion fracture patent ductus arteriosus patent foramen ovale patient information pelvic MRI pericardial fat phaeochromocytoma pharmaceutical writting pineal tumour placenta accreta placenta increta placental insufficiency pneumococcal pneumonia polycystic kidney disease portal Hypertension posterior circulation stroke power point presentation primary complex protected health information pseudobulbar palsy pseudomyxoma peritonei publications pulmonary edema pulmonary embolism pulmonary tuberculosis rabbit ear sign rad radiographic deterioration pattern radiography radiolo radiologist blogs radiology city radiology debate radiology images of spleen radiology intervensional radiology learning radiology search engine radiology spotter radiology spotters radiolopolis raditudes rathke cleft cyst renal imaging renal sinus tumour right sided aortic arch robot round cell tumour sacral agenesis scaphoid fracture schatzki ring scientific content screening search engine secondaries secondary ossification centres silicosis social radiology soft tissue chondroma solitary pulmonary nodule spectroscopy spinal arachnoid cyst spinal cord tumours spinal osteochondroma spine tumour spinoglenoid cyst sternal tuberculosis stress fracture sacrum stroke mri sub-acute combined degeneration subclavian pseudoaneurysm subependymal giant cell astrocytoma sumer sethi swyer-james syndrome syringomyelia tb teaching video teleradiolo teleradiology business models teleradproviders teleultrasound temporal bone fracture tendoachilles testicular tumour tethered cord. MRI tibial stress fracture total knee arthroplasty total shoulder replacment trachea. tracheal diverticulum tracheal stenosis tracheomalacia traumatic lung cyst triceps tear triquetral fracture tubercular abscess tuberculoma tuberculosis elbow ultrasound image of The segments of the liver umblical artery doppler uroradiology vascular malformation vasovist venous angioma ventriculitis video ct scan video mri viral encephalitis vitamin deficiency