Turner White CommunicationsAbout TWCSubscribeContact TWCHomeSearch
Hospital PhysicianJCOMSMPBRMsCart
Current Contents
Past Issue Archives
Interactive:
Self-Assessment Questions
Review of
Clinical Signs
Clinical Review
Quiz
Pediatric Rounds
Resident Grand Rounds
Article Archives
Case Reports
Clinical Practice
Exams
Pediatric Rounds
Resident Grand Rounds
Review of
Clinical Signs

Guide to Reading
Hospital Physician
Editorial Board
Information for Authors

Reprints, Permissions, & Copyright
Site Map
Self-Assessment Questions


Urology


Answer 1
  1. MRI of the abdomen and pelvis. Plasma free metanephrine is 99% specific and 89% sensitive in the diagnosis of pheochromocytoma.1 Once there is strong biochemical evidence of pheochromocytoma, imaging is necessary to define features, such as anatomical relationships, invasion, and multifocality, before surgical intervention can be undertaken. Contrast-enhanced CT and gadolinium-enhanced MRI demonstrate similar sensitivity (90%-100%) and specificity (70%-80%) for pheochromocytoma.2 In a patient with renal insufficiency, MRI is the imaging study of choice because iodinated contrast used with CT is nephrotoxic. Pheochromocytoma typically has high signal intensity on T2-weighted MRI. Fine-needle biopsy of a suspected pheochromocytoma is contraindicated and can cause life-threatening changes in blood pressure.

    REFERENCES
    1. Lenders JW, Pacak K, Walther MM, et al. Biochemical diagnosis of pheochromocytoma: which test is best? JAMA 2002;287:1427-34.

    2. Lumachi F, Tregnaghi A, Zucchetta P, et al. Sensitivity and positive predictive value of CT, MRI and 123I-MIBG scintigraphy in localizing pheochromocytomas: a prospective study. Nucl Med Commun 2006;27:583-7.

Click here to return to the questions

 

Hospital Physician     JCOM     Seminars in Medical Practice
Hospital Physician Board Review Manuals
About TWC    Subscribe    Contact TWC    Home    Search   Site Map

Copyright © 2009, Turner White Communications
Updated 1/04/08 • kkj