eMedicine Specialties > Radiology > Vascular/Interventional

Gastrointestinal Bleeding, Lower: Imaging

Author: Atif Rana, MBBS, Assistant Professor, Department of Radiology, Shifa College of Medicine, Islamabad, Pakistan
Contributor Information and Disclosures

Updated: Apr 13, 2009

Radiography

Findings

After resuscitation of the patient, diagnostic and therapeutic steps are taken. Colonoscopy is the procedure of choice, according to guidelines published by American Society for Gastrointestinal Endoscopy in 2001 (updated 2005). According to these guidelines, angiography should be performed in cases of massive bleeding. Scintigraphy and/or angiography also play important role in diagnosis and embolization when colonoscopy reveals negative findings or when it is not feasible.

Colonoscopy

Colonoscopy after rapid oral purging is recommended for the evaluation of acute lower GI bleeding. This procedure has a yield of 69-80%. As mentioned earlier, bleeding diverticula and angiodysplasia are the most common causes. However, about 10% of cases are ultimately found to involve an upper GI source of bleeding. For this reason, some also advocate an upper GI endoscopy after colonoscopy yields negative results.4

Colonoscopy also provides a mean for therapy in cases of lower GI bleeding. This procedure involves the use of thermal contact modalities or epinephrine injections in cases of diverticula and vascular ectasia. Similarly, other causes of lower GI bleeding can be effectively treated during colonoscopy.

Radiology

The 2 widely used diagnostic tests for lower GI bleeding are nuclear scanning during episodes of bleeding or arteriography.

Scintigraphy

Since late 1970s, technetium-99m sulfur colloid and99m Tc-labeled RBCs have been used in the evaluation of GI bleeding. In 1977, Alavi et al described use of99m Tc sulfur colloid tests for diagnosis of bleeding induced in the small bowel and colon of dogs.5 Bleeding rates as low as 0.05-0.1 mL/min can be detected. The disadvantage of sulfur colloid scanning is the potential masking of bleeding in the upper abdomen by activity in the liver and spleen.99m Tc-labeled RBC scanning does not have this problem, and an animal study by Thorne et al in 1987 showed bleeding detection rates as low as 0.04 mL/min, which are comparable to those of sulfur colloid scanning.6

Bunker et al compared the 2 techniques and found that99m Tc RBC scanning was superior to sulfur colloid scanning.7 The former demonstrated a sensitivity of 93%, a specificity of 95%, and an overall accuracy of 94% in detecting and localizing GI hemorrhage. Initial studies showed acceptable sensitivities for GI bleeding, but a few studies in late 1980s raised doubts about the accuracy of scintigraphic studies. One group reported inaccurate localization leading to a surgical error rate of 42%. Some claim that most available reports in literature base their conclusions on results obtained with older techniques. The newer techniques involve more dynamic imaging (more frequent acquisition of data), extra large field-of-view gamma cameras, and cine scintigraphy or movie-mode displays. Later studies have shown that RBC scans have an accuracy of nearly 90% in the localization of the bleeding site.

Scintigraphy is reported to increase the diagnostic yield of angiography. Gunderman et al showed that, without scintigraphic screening, angiograms depicted bleeding at a rate of 22%.8 After the implementation of scintigraphic screening, 53% of the arteriograms depicted bleeding. In another study, Ng et al showed that, when99m Tc RBC scans showed immediate blush, patients required urgent angiography.9 In contrast, patients whose scans showed delayed blush have low angiographic yields. They recommended that, when scans show delayed blush or negative results, patients may be observed and evaluated with colonoscopy.

The advantages of "bleeding" scanning are that it is noninvasive and that it requires no special patient preparation.10 Bleeding is diagnosed when an abnormal focus of activity is seen. This activity increases over time and changes in position due to peristalsis. An advantage of99m Tc RBC scanning is that repeat imaging can be performed after an interval of as long as 24 hours.

Angiography

The earliest description of the angiographic demonstration of GI bleeding was in 1963. Since that time, angiography has been used in evaluation of GI bleeding, though with varying frequency over time and with the advent of colonoscopy and scintigraphy.

Lower gastrointestinal bleeding. Postembolization...

Lower gastrointestinal bleeding. Postembolization selective angiogram. No further extravasation of contrast material is seen. Polyvinyl alcohol particles were used.

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Lower gastrointestinal bleeding. Postembolization...

Lower gastrointestinal bleeding. Postembolization selective angiogram. No further extravasation of contrast material is seen. Polyvinyl alcohol particles were used.


Lower gastrointestinal bleeding. Patient with an ...

Lower gastrointestinal bleeding. Patient with an acute lower gastrointestinal bleeding. Inferior mesenteric arteriogram shows extravasation of contrast material in the sigmoid colon.

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Lower gastrointestinal bleeding. Patient with an ...

Lower gastrointestinal bleeding. Patient with an acute lower gastrointestinal bleeding. Inferior mesenteric arteriogram shows extravasation of contrast material in the sigmoid colon.


Lower gastrointestinal bleeding. Postembolization...

Lower gastrointestinal bleeding. Postembolization arteriogram shows no further bleeding. Microcoils and polyvinyl alcohol were used.

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Lower gastrointestinal bleeding. Postembolization...

Lower gastrointestinal bleeding. Postembolization arteriogram shows no further bleeding. Microcoils and polyvinyl alcohol were used.


Screen-film arteriography can demonstrate bleeding at rates as low as 0.5 mL/min in dogs, although some authors claim that the actual detectable rate of bleeding in clinical conditions may be in the range of 1.0-1.5 mL/min. Digital subtraction angiography (DSA) has been reported to be more sensitive than conventional screen-film angiography. In 1988, Rees et al showed that DSA tended to be more sensitive than conventional angiography in depicted simulated extravasation in vitro; however, in the clinical study, DSA was severely limited in evaluation of the lower GI tract because of misregistration artifact caused by bowel motion.11 In another study, Kruger et al showed similar findings.12 They reported that DSA was superior to conventional angiography, provided that it is performed with adequate parasympathicolysis and suspended respiration.

On angiograms, hemorrhage is identified as the extravasation of contrast material into the lumen of the bowel. The contrast material extravasation can be free or pooling, and it persists during or even after the injection. The angiodysplasia has been described to have characteristic appearance. It appears as a vascular tuft, along with an early and persistent draining vein.

The clinical sensitivity of angiography has been reported variably in different studies.13 The typical values are around 60%. Attempts to identify predictors for positive angiographic findings have shown mixed results. In a retrospective study, Pennoyer et al did not identify any single useful predictor to increase the likelihood of obtaining a positive angiographic result.14 Evaluated factors included a history of prior GI bleeding, transfusions, orthostatic hypotension, and tachycardia. However, Nicholson et al found a perfect correlation between a systolic blood pressure of less than 100 mm Hg and a positive arteriographic result.15 Therefore, some clinicians advocate immediate arteriography rather than nuclear medicine imaging in hemodynamically unstable patients.

Pharmacologic techniques have been used to increase the diagnostic yield of arteriography. These include the use of heparin, vasodilators, and thrombolytics. The reported studies show a 33-65% increase in the yield of angiography. These small studies have not shown any significant complications, although larger studies are needed to prove safety of this method.

New advances are being made with computed tomographic angiography (CTA) and magnetic resonance angiography (MRA). Junquera et al used CTA to evaluate suspected colonic angiodysplasia.16 The sensitivity, specificity, and positive predictive values of CTA in the detection of colonic angiodysplasia were 70%, 100%, and 100%, respectively, compared with findings of angiography or colonoscopy. In an animal study, Hilfiker et al evaluated use of 3-dimensional (3D) MRI.17 They compared99m Tc RBC scintigraphy with 3D MRI after the intravascular administration of contrast agent. MRI had 100% sensitivity and specificity, compared with 78% sensitivity and 72% specificity for scintigraphy.

More on Gastrointestinal Bleeding, Lower

Overview: Gastrointestinal Bleeding, Lower
Imaging: Gastrointestinal Bleeding, Lower
Follow-up: Gastrointestinal Bleeding, Lower
Multimedia: Gastrointestinal Bleeding, Lower
References
Further Reading
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References

  1. Martín Martín L, Trapero-Marugán M, Cantero Perona J, Moreno Otero R. [Difficulties and controversies in hospitalized patients with lower gastrointestinal bleeding]. Rev Esp Enferm Dig. Sep 2008;100(9):560-4. [Medline].

  2. Pérez Folqués JE, Fernández Moreno J, Vázquez Ruiz J, Civera Muñoz FJ, Mansilla Molina D, Guirao Manzano J, et al. [Meckel's diverticulum as a cause of lower gastrointestinal bleeding in adults]. Rev Esp Enferm Dig. Sep 2008;100(9):595-6. [Medline].

  3. Hotta T, Takifuji K, Tonoda S, Mishima H, Sasaki M, Yukawa H, et al. Risk factors and management for massive bleeding of an acute hemorrhagic rectal ulcer. Am Surg. Jan 2009;75(1):66-73. [Medline].

  4. Saruta M, Papadakis KA. Capsule endoscopy in the evaluation and management of inflammatory bowel disease: a future perspective. Expert Rev Mol Diagn. Jan 2009;9(1):31-6. [Medline].

  5. Alavi A, Dann RW, Baum S, Biery DN. Scintigraphic detection of acute gastrointestinal bleeding. Radiology. Sep 1977;124(3):753-6. [Medline].

  6. Thorne DA, Datz FL, Remley K, Christian PE. Bleeding rates necessary for detecting acute gastrointestinal bleeding with technetium-99m-labeled red blood cells in an experimental model. J Nucl Med. Apr 1987;28(4):514-20. [Medline].

  7. Bunker SR, Lull RJ, Tanasescu DE, et al. Scintigraphy of gastrointestinal hemorrhage: superiority of 99mTc red blood cells over 99mTc sulfur colloid. AJR Am J Roentgenol. Sep 1984;143(3):543-8. [Medline].

  8. Gunderman R, Leef J, Ong K, et al. Scintigraphic screening prior to visceral arteriography in acute lower gastrointestinal bleeding. J Nucl Med. Jun 1998;39(6):1081-3. [Medline].

  9. Ng DA, Opelka FG, Beck DE, et al. Predictive value of technetium Tc 99m-labeled red blood cell scintigraphy for positive angiogram in massive lower gastrointestinal hemorrhage. Dis Colon Rectum. Apr 1997;40(4):471-7. [Medline].

  10. Tulchinsky M. Lower gastrointestinal bleeding diagnosed by red blood cell scintigraphy in a patient with a left ventricular assist device. Clin Nucl Med. Dec 2008;33(12):856-8. [Medline].

  11. Rees CR, Palmaz JC, Alvarado R, et al. DSA in acute gastrointestinal hemorrhage: clinical and in vitro studies. Radiology. Nov 1988;169(2):499-503. [Medline].

  12. Kruger K, Heindel W, Dolken W, et al. Angiographic detection of gastrointestinal bleeding. An experimental comparison of conventional screen-film angiography and digital subtraction angiography. Invest Radiol. Jul 1996;31(7):451-7. [Medline].

  13. Karanicolas PJ, Colquhoun PH, Dahlke E, Guyatt GH. Mesenteric angiography for the localization and treatment of acute lower gastrointestinal bleeding. Can J Surg. Dec 2008;51(6):437-41. [Medline].

  14. Pennoyer WP, Vignati PV, Cohen JL. Mesenteric angiography for lower gastrointestinal hemorrhage: are there predictors for a positive study?. Dis Colon Rectum. Sep 1997;40(9):1014-8. [Medline].

  15. Nicholson ML, Neoptolemos JP, Sharp JF, et al. Localization of lower gastrointestinal bleeding using in vivo technetium-99m-labelled red blood cell scintigraphy. Br J Surg. Apr 1989;76(4):358-61. [Medline].

  16. Junquera F, Quiroga S, Saperas E, et al. Accuracy of helical computed tomographic angiography for the diagnosis of colonic angiodysplasia. Gastroenterology. Aug 2000;119(2):293-9. [Medline].

  17. Hilfiker PR, Weishaupt D, Kacl GM, et al. Comparison of three dimensional magnetic resonance imaging in conjunction with a blood pool contrast agent and nuclear scintigraphy for the detection of experimentally induced gastrointestinal bleeding. Gut. Oct 1999;45(4):581-7. [Medline].

  18. Bookstein JJ, Chlosta EM, Foley D, Walter JF. Transcatheter hemostasis of gastrointestinal bleeding using modified autogenous clot. Radiology. Nov 1974;113(2):277-85. [Medline].

  19. Evangelista PT, Hallisey MJ. Transcatheter embolization for acute lower gastrointestinal hemorrhage. J Vasc Interv Radiol. May 2000;11(5):601-6. [Medline].

  20. Bandi R, Shetty PC, Sharma RP, et al. Superselective arterial embolization for the treatment of lower gastrointestinal hemorrhage. J Vasc Interv Radiol. Dec 2001;12(12):1399-405. [Medline].

  21. Alavi A, Ring EJ. Localization of gastrointestinal bleeding: superiority of 99mTc sulfur colloid compared with angiography. AJR Am J Roentgenol. Oct 1981;137(4):741-8. [Medline].

  22. Amonoo-Kuofi HS, el-Badawi MG, el-Naggar ME. Anomalous origins of colic arteries. Clin Anat. 1995;8(4):288-93. [Medline].

  23. Athanasoulis CA, Baum S, Rosch J, et al. Mesenteric arterial infusions of vasopressin for hemorrhage from colonic diverticulosis. Am J Surg. Feb 1975;129(2):212-6. [Medline].

  24. Baum S, Rosch J, Dotter CT, et al. Selective mesenteric arterial infusions in the management of massive diverticular hemorrhage. N Engl J Med. Jun 14 1973;288(24):1269-72. [Medline].

  25. Bloomfeld RS, Smith TP, Schneider AM, Rockey DC. Provocative angiography in patients with gastrointestinal hemorrhage of obscure origin. Am J Gastroenterol. Oct 2000;95(10):2807-12. [Medline].

  26. DeBarros J, Rosas L, Cohen J, et al. The changing paradigm for the treatment of colonic hemorrhage: superselective angiographic embolization. Dis Colon Rectum. Jun 2002;45(6):802-8. [Medline].

  27. Dusold R, Burke K, Carpentier W, Dyck WP. The accuracy of technetium-99m-labeled red cell scintigraphy in localizing gastrointestinal bleeding. Am J Gastroenterol. Mar 1994;89(3):345-8. [Medline].

  28. Eisen GM, Dominitz JA, Faigel DO, et al. An annotated algorithmic approach to acute lower gastrointestinal bleeding. Gastrointest Endosc. Jun 2001;53(7):859-63. [Medline].

  29. Funaki B, Kostelic JK, Lorenz J, et al. Superselective microcoil embolization of colonic hemorrhage. AJR Am J Roentgenol. Oct 2001;177(4):829-36. [Medline].

  30. Gerlock AJ Jr, Muhletaler CA, Berger JL, et al. Infarction after embolization of the ileocolic artery. Cardiovasc Intervent Radiol. 1981;4(3):202-5. [Medline].

  31. Gomes AS, Lois JF, McCoy RD. Angiographic treatment of gastrointestinal hemorrhage: comparison of vasopressin infusion and embolization. AJR Am J Roentgenol. May 1986;146(5):1031-7. [Medline].

  32. Gordon RL, Ahl KL, Kerlan RK, et al. Selective arterial embolization for the control of lower gastrointestinal bleeding. Am J Surg. Jul 1997;174(1):24-8. [Medline].

  33. Gutierrez C, Mariano M, Vander Laan T, et al. The use of technetium-labeled erythrocyte scintigraphy in the evaluation and treatment of lower gastrointestinal hemorrhage. Am Surg. Oct 1998;64(10):989-92. [Medline].

  34. Guy GE, Shetty PC, Sharma RP, et al. Acute lower gastrointestinal hemorrhage: treatment by superselective embolization with polyvinyl alcohol particles. AJR Am J Roentgenol. Sep 1992;159(3):521-6. [Medline].

  35. Hastings GS. Angiographic localization and transcatheter treatment of gastrointestinal bleeding. Radiographics. Jul-Aug 2000;20(4):1160-8. [Medline].

  36. Holder LE. Radionuclide imaging in the evaluation of acute gastrointestinal bleeding. Radiographics. Jul-Aug 2000;20(4):1153-9. [Medline].

  37. Hunter JM, Pezim ME. Limited value of technetium 99m-labeled red cell scintigraphy in localization of lower gastrointestinal bleeding. Am J Surg. May 1990;159(5):504-6. [Medline].

  38. Jensen DM, Machicado GA. Diagnosis and treatment of severe hematochezia. The role of urgent colonoscopy after purge. Gastroenterology. Dec 1988;95(6):1569-74. [Medline].

  39. Jensen DM, Machicado GA, Jutabha R, Kovacs TO. Urgent colonoscopy for the diagnosis and treatment of severe diverticular hemorrhage. N Engl J Med. Jan 13 2000;342(2):78-82. [Medline].

  40. Kim BC, Cheon JH, Kim TI, Kim WH. Risk factors and the role of bedside colonoscopy for lower gastrointestinal hemorrhage in critically ill patients. Hepatogastroenterology. Nov-Dec 2008;55(88):2108-11. [Medline].

  41. Koval G, Benner KG, Rosch J, Kozak BE. Aggressive angiographic diagnosis in acute lower gastrointestinal hemorrhage. Dig Dis Sci. Mar 1987;32(3):248-53. [Medline].

  42. Ledermann HP, Schoch E, Jost R, et al. Superselective coil embolization in acute gastrointestinal hemorrhage: personal experience in 10 patients and review of the literature. J Vasc Interv Radiol. Sep-Oct 1998;9(5):753-60. [Medline].

  43. Lefkovitz Z, Cappell MS, Kaplan M, et al. Radiology in the diagnosis and therapy of gastrointestinal bleeding. Gastroenterol Clin North Am. Jun 2000;29(2):489-512. [Medline].

  44. Longstreth GF. Epidemiology and outcome of patients hospitalized with acute lower gastrointestinal hemorrhage: a population-based study. Am J Gastroenterol. Mar 1997;92(3):419-24. [Medline].

  45. Luchtefeld MA, Senagore AJ, Szomstein M, et al. Evaluation of transarterial embolization for lower gastrointestinal bleeding. Dis Colon Rectum. Apr 2000;43(4):532-4. [Medline].

  46. Nicholson AA, Ettles DF, Hartley JE, et al. Transcatheter coil embolotherapy: a safe and effective option for major colonic haemorrhage. Gut. Jul 1998;43(1):79-84. [Medline].

  47. Orecchia PM, Hensley EK, McDonald PT, Lull RJ. Localization of lower gastrointestinal hemorrhage. Experience with red blood cells labeled in vitro with technetium Tc 99m. Arch Surg. May 1985;120(5):621-4. [Medline].

  48. Peck DJ, McLoughlin RF, Hughson MN, Rankin RN. Percutaneous embolotherapy of lower gastrointestinal hemorrhage. J Vasc Interv Radiol. Sep-Oct 1998;9(5):747-51. [Medline].

  49. Pianka JD, Affronti J. Management principles of gastrointestinal bleeding. Prim Care. Sep 2001;28(3):557-75, vi. [Medline].

  50. Rantis PC Jr, Harford FJ, Wagner RH, Henkin RE. Technetium-labelled red blood cell scintigraphy: is it useful in acute lower gastrointestinal bleeding?. Int J Colorectal Dis. 1995;10(4):210-5. [Medline].

  51. Rosch J, Keller FS, Wawrukiewicz AS, et al. Pharmacoangiography in the diagnosis of recurrent massive lower gastrointestinal bleeding. Radiology. Dec 1982;145(3):615-9. [Medline].

  52. Rosenkrantz H, Bookstein JJ, Rosen RJ, et al. Postembolic colonic infarction. Radiology. Jan 1982;142(1):47-51. [Medline].

  53. Ryan JM, Key SM, Dumbleton SA, Smith TP. Nonlocalized lower gastrointestinal bleeding: provocative bleeding studies with intraarterial tPA, heparin, and tolazoline. J Vasc Interv Radiol. Nov 2001;12(11):1273-7. [Medline].

  54. Smith R, Copely DJ, Bolen FH. 99mTc RBC scintigraphy: correlation of gastrointestinal bleeding rates with scintigraphic findings. AJR Am J Roentgenol. May 1987;148(5):869-74. [Medline].

  55. Uflacker R. Transcatheter embolization for treatment of acute lower gastrointestinal bleeding. Acta Radiol. Jul-Aug 1987;28(4):425-30. [Medline].

  56. Vernava AM 3rd, Moore BA, Longo WE, Johnson FE. Lower gastrointestinal bleeding. Dis Colon Rectum. Jul 1997;40(7):846-58. [Medline].

  57. Voeller GR, Bunch G, Britt LG. Use of technetium-labeled red blood cell scintigraphy in the detection and management of gastrointestinal hemorrhage. Surgery. Oct 1991;110(4):799-804. [Medline].

  58. Winzelberg GG, Froelich JW, McKusick KA, et al. Radionuclide localization of lower gastrointestinal hemorrhage. Radiology. May 1981;139(2):465-9. [Medline].

  59. Wu Y, Seto H, Shimizu M, et al. Sequential subtraction scintigraphy with 99Tcm-RBC for the early detection of gastrointestinal bleeding and the calculation of bleeding rates: phantom and animal studies. Nucl Med Commun. Feb 1997;18(2):129-38. [Medline].

  60. Zuckerman DA, Bocchini TP, Birnbaum EH. Massive hemorrhage in the lower gastrointestinal tract in adults: diagnostic imaging and intervention. AJR Am J Roentgenol. Oct 1993;161(4):703-11. [Medline].

  61. Zuckerman GR, Prakash C. Acute lower intestinal bleeding. Part II: etiology, therapy, and outcomes. Gastrointest Endosc. Feb 1999;49(2):228-38. [Medline].

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Further Reading

Clinical guidelines
ASGE guideline: the role of endoscopy in the patient with lower-GI bleeding.
American Society for Gastrointestinal Endoscopy - Medical Specialty Society.  2005 Nov.  5 pages.  NGC:004584

Management of acute upper and lower gastrointestinal bleeding. A national clinical guideline. Scottish Intercollegiate Guidelines Network - National Government Agency [Non-U.S.].  2008 Sep.  57 pages.  NGC:006730

Clinical trials

 Diagnostic Evaluation of Obscure Gastrointestinal Bleeding

Related eMedicine topics

 Lower Gastrointestinal Bleeding (gastroenterology)

Lower Gastrointestinal Bleeding: Surgical Perspective

Diverticular Disease (emergency medicine)

Pediatrics, Gastrointestinal Bleeding

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Keywords

lower gastrointestinal bleeding, GI bleeding, lower GI bleeding, gastrointestinal hemorrhage, GI hemorrhage

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Contributor Information and Disclosures

Author

Atif Rana, MBBS, Assistant Professor, Department of Radiology, Shifa College of Medicine, Islamabad, Pakistan
Atif Rana, MBBS is a member of the following medical societies: Radiological Society of North America
Disclosure: Nothing to disclose.

Medical Editor

Anthony Watkinson, MD, Professor of Interventional Radiology, The Peninsula Medical School; Consultant and Senior Lecturer, Department of Radiology, The Royal Devon and Exeter Hospital, UK
Anthony Watkinson, MD is a member of the following medical societies: Radiological Society of North America, Royal College of Radiologists, and Royal College of Surgeons of England
Disclosure: Nothing to disclose.

Pharmacy Editor

Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand
Disclosure: Nothing to disclose.

Managing Editor

Douglas M Coldwell, MD, PhD,, Principal, Coldwell Associates. Interventional Radiologist, Jane Phillips Medical Center, Bartlesville, OK
Douglas M Coldwell, MD, PhD, is a member of the following medical societies: American Association for Cancer Research, American College of Radiology, American Heart Association, American Physical Society, American Roentgen Ray Society, Society of Cardiovascular and Interventional Radiology, Southwest Oncology Group, and Special Operations Medical Association
Disclosure: Sirtex, Inc. Consulting fee Speaking and teaching

CME Editor

Robert M Krasny, MD, Consulting Staff, Department of Radiology, Resolution Imaging Medical Corporation
Robert M Krasny, MD is a member of the following medical societies: American Roentgen Ray Society and Radiological Society of North America
Disclosure: Nothing to disclose.

Chief Editor

Kyung J Cho, MD, FACR, William Martel Professor of Radiology, Interventional Radiology Fellowship Director, University of Michigan Health System
Kyung J Cho, MD, FACR is a member of the following medical societies: American College of Radiology, American Heart Association, American Medical Association, American Roentgen Ray Society, Association of University Radiologists, and Radiological Society of North America
Disclosure: Nothing to disclose.

 
 
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