急性胰腺炎影像学检查价值

Matthew Lewis, HMSIV Gillian Lieberman, MD Acute Pancreatitis – Why Imaging is our Friend ™ Matthew Lewis HMS IV ™ Gillian Lieberman, MD July 25, 2005 Matthew Lewis, HMSIV Gillian Lieberman, MD The Patient! ™ H.S. is a 43 y.o. male presenting with intense abdominal pain and several episodes of emesis ™ PE reveals distressed, obese man with significant epigastric tenderness radiating to back ™ Lab studies show elevated serum amylase, elevated serum lipase, WBC of 17,000, glucose of 220, LDH of 330 What is our next step? Matthew Lewis, HMSIV Gillian Lieberman, MD For New Pathway students yalenewhavenhealth.org/.../ medical/hw/n2192.jpg Matthew Lewis, HMSIV Gillian Lieberman, MD Basic Anatomy ™ http://www.cosmovisions.com/pancreas.jpg Important structures? http://pathology2.jhu.edu/pancreas/images/shape.gif Matthew Lewis, HMSIV Gillian Lieberman, MD CT Anatomy 1 3 4 51 3 4 5 6 7 8 2codeblueblog.blogs.com/.../ normal_pancreas.jpg Matthew Lewis, HMSIV Gillian Lieberman, MD www.bmb.leeds.ac.uk/.../ practic/anat/Image42.jpg Which spaces are most frequently involved in pancreatic fluid collections? codeblueblog.blogs.com/.../ normal_pancreas.jpg Matthew Lewis, HMSIV Gillian Lieberman, MD To image or not to image… Pancreatitis is a clinical diagnosis -- why image? ™ Confirmation of diagnosis ™ Evaluation of severity and complications – Contrast enables assessment of perfusion and allows for estimation of necrosis – Enables detection and delineation of pancreatic fluid collections (size, location, contents, suitability for drainage) Matthew Lewis, HMSIV Gillian Lieberman, MD Modality Options Ultrasound • Often difficult to visualize the pancreas during acute phase of pancreatitis due to illeus • May be useful in following complications of pancreatitis during convalescent phase • Evolution of fluid collections • Areas of arterial or portal thrombosis via Doppler Matthew Lewis, HMSIV Gillian Lieberman, MD Sample Image – U/S www.bchsys.org/.../ ImagingAbUltrasound.htm Matthew Lewis, HMSIV Gillian Lieberman, MD MRI ™ Strengths: – Just as effective as CT in detailing necrosis and the site and character of fluid collections. May be better than CT at imaging internal consistency and drainability of collections – No iodinated contrast or radiation ™ Weaknesses: – CT more accessible, cheaper – CT more sensitive for small gas bubbles, calcifications – CT more conducive to insertion and monitoring of drainage devices ™ MRI with increasing use in chronic pancreatitis and pancreatic adenocancer Modality Options Matthew Lewis, HMSIV Gillian Lieberman, MD Modality Options CT: Gold standard for evaluation of pancreatitis ™ Spiral CT with contrast preferable study ™ Strengths: – Accessibility, cost, speed, detail, staging – Compatible with intervention ™ Weaknesses: – Iodinated Contrast (some studies suggest worsens pancreatitis) – Radiation load Matthew Lewis, HMSIV Gillian Lieberman, MD CT severity Index Inflammatory process: Score: A: Normal Pancreas 0 B: Pancreatic enlargement 1 C: Inflammation or peripancreatic fat stranding 2 D: Single peripancreatic fluid collection 3 E: Two or more fluid collections or retroperitoneal air 4 Gland Necrosis: 1)No necrosis 0 2) <30% 2 3) 30-50% 4 4) >50% 6 Matthew Lewis, HMSIV Gillian Lieberman, MD Early Pancreatitis What’s the Grade? Courtesy Dr. Anne Kim Matthew Lewis, HMSIV Gillian Lieberman, MD CTSI and outcome ™ CTSI 0-3: – 3% Mortality – 8% Morbidity ™ CTSI 7-10: – 17% Mortality – 92% Morbidity Matthew Lewis, HMSIV Gillian Lieberman, MD Pitfalls in staging 1. Necrosis takes 2-3 days to be evident on scan 2. Sensitivity in detecting necrosis proportional to size of necrotic area 3. Difficult to detect retroperitoneal fat necrosis Matthew Lewis, HMSIV Gillian Lieberman, MD Back to our Patient! ™ H.S. admitted, treated with IV fluids ™ What are early systemic complications of pancreatitis? ™ Medical grading systems? ™ In order to assess severity of H.S.’s case, CT is performed… Matthew Lewis, HMSIV Gillian Lieberman, MD H.S. first scan Courtesy Dr. Alice Fisher Matthew Lewis, HMSIV Gillian Lieberman, MD Complications I Pancreatic necrosis: ™ >80% of deaths occur in patients with necrosis – Mortality Dependent on extent of parenchymal injury – Appears as areas of decreased attenuation – Occurs in 20% of patients with acute pancreatitis ™ Infection occurs in 5-10% of pts with necrosis -- – May see gas bubbles – Common organisms? – Requires aggressive management Matthew Lewis, HMSIV Gillian Lieberman, MD Complications II Pancreatic Abscess ™ Poorly encapsulated collection of pus – 3% of cases – Appears as low-attenuated fluid collections +/- the presence of air – Diagnosis confirmed with FNA ™ Treatment and course differ from infected fat necrosis Matthew Lewis, HMSIV Gillian Lieberman, MD Several weeks later… Courtesy Dr. Alice Fisher Matthew Lewis, HMSIV Gillian Lieberman, MD Complications III Pseudocysts: encapsulated pancreatic fluid collections ™ Failure of resorption pancreatic secretions, presence of communicating tracts – Develop >4 months post acute – Often develop from resolving aseptic necrosis – Surgical or percutaneous drainage indicated for cyst larger than 5cm, older than 6 weeks, enlarging cysts, or symptomatic (painful, gastric or bilary outlet obstruction) Matthew Lewis, HMSIV Gillian Lieberman, MD Other Complications ™ GI and biliary complications – Sinus tract formation, fistulas, colonic spasm ™ Solid organ involvement – Splenic infarcts, hemorrhage, jaundice ™ Vascular complications – Thrombosis, hemorrhage ™ Ascites – Transient vs. pancreactic ascites Matthew Lewis, HMSIV Gillian Lieberman, MD Things aren’t looking good… Courtesy Dr. Alice Fisher Matthew Lewis, HMSIV Gillian Lieberman, MD Ascites Courtesy Dr. Vassilios Raptopoulos Matthew Lewis, HMSIV Gillian Lieberman, MD Percutaneous drainage ™ Require drainage if: – Symptomatic – >5 cm ™ Retroperitoneal, trans-gastric, trans-hepatic routes all shown to be effective ™ Aspiration – Most do not recur (if do: catheter placement) – Analysis of fluid if diagnosis is in doubt Matthew Lewis, HMSIV Gillian Lieberman, MD Status post drainage Courtesy Dr. Alice Fisher Matthew Lewis, HMSIV Gillian Lieberman, MD Homer finds relief ™ Following drainage, H.S. feels better, but a catheter is left in place to allow for continual drainage ™ Fluid accumulation shows no signs of infection following labs ™ Will H.S. need surgery? Matthew Lewis, HMSIV Gillian Lieberman, MD Points to Remember ™ Imaging of pancreatitis allows for confirmation of diagnosis and assessment and grading of complications and severity ™ Currently, CT preferred imaging modality ™ Pancreatic Necrosis evident on CT and strong indicator of outcome ™ CT guided drainage is effective treatment for psuedocysts and fluid collections Matthew Lewis, HMSIV Gillian Lieberman, MD Acknowledgments ™ Dr. Gillian Lieberman ™ Dr. Anne Kim ™ Dr. Vassilios Raptopoulos ™ Dr. Alice Fisher ™ Pamela Lepkowski ™ Clotell Forde Matthew Lewis, HMSIV Gillian Lieberman, MD Resources ™ Balthazar, E. Staging of acute pancreatitis. Radiol Clin N Am. (2002) 40:1199-1209. ™ Balthazar, E. Complications of acute pancreatitis CT evaluation. Radiol Clin N Am. (2002) 40:1211-1227. ™ Elmas, N. The role of diagnostic radiology in pancreatitis. (2001) 38:120-132. ™ Keim, V. Diagnosis and treatment of acute pancreatitis. Z. Gastroenterol. (2005). 43:461-6. ™ Pamkular, E. MR imaging of the pancreas. Magn Reson Imaging Clin N Am. (2005). 13: 313-330. ™ Robinson, A; Sheridan, M. Pancreatitis: CT and MRI. Eur. Radiol. (2000) 401-408. Acute Pancreatitis – Why Imaging is our Friend The Patient! For New Pathway students Basic Anatomy CT Anatomy Slide Number 6 To image or not to image… Modality Options Sample Image – U/S Modality Options Modality Options CT severity Index Early Pancreatitis CTSI and outcome Pitfalls in staging Back to our Patient! H.S. first scan Complications I Complications II Several weeks later… Complications III Other Complications Things aren’t looking good… Ascites Percutaneous drainage Status post drainage Homer finds relief Points to Remember Acknowledgments Resources