الفهرس 
AnatomyOnly 14 pages are availabe for public view
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Abstract
MDCT has gained a great role in clinical imaging practice in a short time. Its major advantages are fast image acquisition and improved resolution. In spite of the advent of other imaging modalities CT is still the gold standard for the evaluation of pancreatic pathology.
MDCT scanning allows quick and accurate diagnosis and staging of pancreatitis. MDCT can assess the degree of involvement and enables detection of complications including development of pseudocysts, abscess, necrosis, hemorrhage, and vascular occlusion.
Acute pancreatitis can be a mild, self-limiting disease or can be severe with significant patient morbidity and mortality. The severity of the patient’s condition is judged based on clinical, laboratory, and imaging criteria. CECT is the imaging modality of choice for evaluation of pancreatitis. It can evaluate pancreatic morphology, detect pancreatic necrosis, and depict retroperitoneal complications, and used to stage the severity of inflammation.
CT staging and CT severity index have proved to be a reliable indicator of disease severity, having shown an excellent correlation with the risk of death and the development of local and systemic complications in this population.
Mortality of acute pancreatitis is dependent on the development of potentially lethal complications that can coexist and occur at any time following an acute attack. The early detection and objective evaluation of these complications by clinical and imaging methods lead to specific treatment options in the continuous attempt to decrease mortality rates in acute pancreatitis.
Imaging plays an important role in the management of patients who have acute pancreatitis. CT and trans-abdominal ultrasound are useful to confirm the diagnosis of acute pancreatitis and to rule out other causes of acute abdomen such as gastrointestinal perforation, acute cholecystitis, acute aortic dissection, and mesenteric artery occlusion. Clinically, all these entities can mimic acute pancreatitis. In established cases of acute pancreatitis, contrast enhanced CT (CECT) is considered the criterion standard for evaluating morphologic changes of the disease, particularly in the assessment of pancreatic necrosis. CECT has become an integral part of the new classification system.
In chronic pancreatitis, contrast-enhanced multidetector CT (MDCT) is well established to assess ductal changes, calcifications, the form and shape of the pancreatic gland, and potential concomitant conditions such as pseudocysts. This also enables multiplanar, curved reconstructions for a high resolution display of the total gland and the course of the duct.
Pancreatic cancer is the 10th common malignancy and the 4th largest cancer killer in adults. Surgery offers the only chance of curing these patients.
Excellent visualization of the pancreatic parenchyma in various phases of contrast enhancement facilitates early detection of small pancreatic lesions.
MDCT and advanced postprocessing techniques, can provide solutions for the difficult problems in the diagnosing and staging disease, and can aid radiologists in communicating findings to surgeons and oncologists. Multiplanar reformats can provide additional information on involvement of the celiac artery, portal vein, hepatic artery, and common bile duct. MIP images and volume rendered images can aid in the identification of important vascular variants.
MIP images can show the relationship of tumour to the pancreatic duct or biliary tree. CPR images can show the relationship of tumour to the pancreatic duct or vascular structures.
Ninety percent of pancreatic adenocarcinoma are unresectable. MDCT is useful to prevent an unnecessary Whipple procedure. CT signs of unresectability include: liver metastasis, ascites, local extension (except duodenum), arterial encasement, and lymph node enlargement outside the field.
Although the majority of cystic lesions of the pancreas seen in clinical practice represent post inflammatory pseudocysts, it is important for the radiologist to be knowledgeable of the wide spectrum of cystic masses of the pancreas and the variable prognoses they possess. As a result of similarities in the imaging features of these lesions, a definitive diagnosis is often not possible. By combining imaging features with clinical history, a reasonable differential diagnosis can be offered to the referring physician. In some cases, biopsy or fluid aspiration may be required prior to surgery.
Multidetector CT technology allows high-resolution multiphasic evaluation of the pancreas for the detection of insulinomas and has promising sensitivities.
In conclusion, contrast enhanced multiphase pancreatic imaging by MDCT with its postprocessing techniques represents the imaging modality of choice for diagnosis of different acquired pancreatic disease.