1 / 30

IMAGING RISK ANALYSIS

This article explores the potential risks and benefits of medical imaging technology, particularly CT scans, highlighting the cumulative effects of ionizing radiation and the overuse of imaging procedures. It also discusses the need for a thorough risk-benefit analysis in each imaging scenario.

henryvwilliams
Download Presentation

IMAGING RISK ANALYSIS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. V VICTIMSO OFM MEDICAL I IMAGING T TECHNOLOGY IMAGING RISK ANALYSIS

  2. WK Mallon MD DTMH, FAAEM, FACEP Associate Professor of Emergency Medicine Keck School of Medicine at USC Los Angeles County + USC Medical Center

  3. CONFLICTS OF INTEREST I work at a Level 1 trauma center that pan-scans trauma patients regularly Made a movie “CODE BLACK” and Sonosite supported that venture (no salary), and obviously UTZ has no ionizing radiation EMA faculty (a source of EBM for this) No HIPAA sensitive material here-in.

  4. AGE AND GENDER Age: more TIME for malignant transformation to occur Age: greater vulnerability of tissues ? Age: intellectual development in process Gender: different tissues for cancer Gender: breast exposures important

  5. FIRST CT is the major exposure to diagnostic radiation accounting for 75-85% of the total THEREFORE, I will focus there NO DOUBT, CT is a fabulous diagnostic tool, that has saved many lives, & advanced diagnosis specific treatments for many…. I DO NOT recommend abandoning this powerful tool in any way

  6. THE QUESTION IS HARM Can a powerful diagnostic tool cause harm? Radiation risks: NO DOUBT they are real Financial risks: NO DOUBT CT imaging is very expensive and a COST contributor Contrast risks: allergy & renal issues Chasing the array of INCIDENTALOMAS is another big problem often ignored in the discussion…… So, HARM is a real problem

  7. LOTS OF HARD DATAREGARDING RADIATION Hiroshima Excess Death Data BEIR VII data Phantom tissue block measurements Clinical measurements of exposures Calculations of Excess Cancers Actual Cancers measurements CT usage data and diagnostic yield estimates

  8. ATOM BOMB SURVIVORS • 550,000 patient years of F/U for 10,500 survivors over the years 1986-1990 • They are still dying: 420 excess deaths here • This data is excellent population whole body dose exposure and resulting cancers which take decades to emerge • “WE DON’T KNOW”…. “military radiation differs” • “Speculation and estimates”….. Pierce DA et al, Radiation Res 1996 July; 146(1): 1-7

  9. RISK / BENEFIT This is THE question, both R & B must be assessed and quantitated in EVERY imaging scenario before you order I offer data suggesting RISK is being ignored, and as a result the use of CT has expanded way beyond medical reason and is being employed way too often with very little patient benefit

  10. IONIZING RADIATION • CT → 6000 cancers per year: 50% fatal • Under-recognized • Clinicians “lack understanding” • Risk benefit assessments lacking • Cumulative dose concerns missing • Unnecessary CT is a problem….. Health Devices. 2007 Feb;36(2):41-2, 44-63

  11. PLUS THE RADIATION RISK IS CUMMULATIVE ! It all adds up:“The cumulative effect of imaging procedures is what’s so troubling, but no one — neither doctors nor patients — seems to be tracking that danger.” (from Scientific American expose) Biological effects of ionizing radiation (BEIR) are unforgiving, the insults keep adding on Thus, total exposure is being ignored.

  12. HAS BENEFIT GONE UP TOO? NO.

  13. UMMM, NO • Washington State database of 85,790 pts! • Compared prior to CT/UTZ/lap outcomes to cases after these modalities were widely employed for appy diagnosis…. • No change in neg lap rate 1987 – 1998 • No change in women, children, elderly • Perforation rates did not decrease either…. Flum DR et al, JAMA 2002 Jan 2; 287(1):43-4

  14. INJURY RELATED CT Panscan strategy is a disaster being employed on low risk patients without benefit From 1998-2007 trauma CT imaging tripled, WITHOUT increased dx, hospitalization, or interventions, or mortality Korley et al JAMA 2010 Ahmadina et al, JoT 2012 Harm ignored in peds trauma Brunetti et al JoT 2011 4.4 xs thyroid Ca deaths, 41.4 xs breast Ca deaths, 13.3 xs leukemia deaths/100,000 pts based on measured (not estimated) exposures Tien et al JoT 2007

  15. PANSCAN BEFORE & AFTER Set 20 mSv as a threshold number: risk for CANCER is greater than 1/1000 at this #. 655 patients before, 624 after panscan intro 12% exceeded threshold before AND 20% exceeded after, without a CHANGE in the missed injury rate Increased exposure WITHOUT benefit! Asha et al, Emerg Med Australasia Feb 2012

  16. TRAUMA TRANSFERS Higher level of care requests, many transferred because a CT at the first hospital made a diagnosis…. (tech issues noted) Then what? REPEAT CT??! A perfect demonstration of medically cavalier approach to radiation risk. 78% of 207 got repeat scans! Liepert et al, J Surg Res 2011 Other studies echo the findings….

  17. NO CT OR OBSERVATION

  18. NEPHROLITHIASIS Marked increase use of CT, but alas, no concommitant increase in stone diagnosis Hyams et al, J Urol 2011 Recurrent condition, some are scanned over and over again ignoring cummulative dose. 19/4000 had 6 or more CTs, and 1 patient had 18 scans! Katz et al, Am J Roent 2006 And there are GOOD alternatives here…..

  19. CARDIAC IMAGING One common statement is why fear “theoretical” future cancer “estimates”? We can’t know, it has never been measured FALSE: McGill U. actually followed cardiac patients with known ionizing medical radiation exposures & measured the resulting non-theoretical cancers Cancer increased 3% for every 10mSv in the as predicted manner Eisenberg et al CMAJ 2011

  20. MALES Age 20: 1 in 686 Age 40: 1 in 1007 Age 60: 1 in 1241 Age 80: 1 in 3261 FEMALES Age 20: 1 in 143 Age 40: 1 in 284 Age 60: 1 in 466 Age 80: 1 in 1338 CT CORONARY ANGIOGRAPHY:LIFETIME ATTRIBUTABLE RISK Eistein AJ et al, JAMA 298(3):317, July 18, 2007

  21. AGE ISSUES: THE YOUNG HAVE GREATER RISK Looked at 200 CTs age < 35 Many deemed unnecessary (or easily replaced by MRI which is superior for the clinical query made by the clinician). In total, 30% of CTs were “unjustified” Oikarinen et al, EurRadiol 2009

  22. THE COSTS & CHARGES For patients it is the charges…. A CT will add $2000 to an ED visit (easy) Patients are harmed by the collections when un or under-insured, or large deductibles In 2007, of 5000 debtors filing for bankruptcy 62% had a medical component! Most had insurance and were employed! Himmelstein et al, Am J Med 2009

  23. LAST, BUT NOT LEAST:INCIDENTALOMAS Commonly found in trauma patients 43% had something, 60% of those warranted further eval, 15% were possible cancers. Munk et al, J Emerg Med 2010 Peds Trauma Head CTs: 4% had non-trauma findings = incidentalomas F/U critical additional element of trauma imaging Rogers et al, Pediatrics 2013

  24. V O M I T IS REALITY • V = Victims • O = Of • M = Medical • I = Imaging • T = Technology

  25. SO IS RISK BEING EXAGGERATED ? Quite the contrary. Risk is largely being ignored ! We have more and more scans with less and less benefit…..the data is irrefutable and from multiple sources HEME ONC is a growth industry!

More Related