MEASURING PEAK SKIN DOSE

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MEASURING PEAK SKIN DOSE

• John H. OConnell
• Adela Salame-Alfie, Ph.D.
• NYSDOH
• David F. Lewis, Ph.D.
• Poppy Pattanayak
• International Specialty Products

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THE NEW YORK STATE DEPARTMENT OF HEALTH BEGAN TO
MEASURE PATIENT ENTRANCE SKIN EXPOSURE
DURING INTERVENTIONAL CARDIOLOGY
PROCEDURES SEVERAL YEARS AGO
OUR INITIAL MEASUREMENTS WERE PERFORMED USING
TLDS MOUNTED ON PLASTIC STRIPS
THE RESULTS WERE SPORADIC SINCE WE DID NOT HAVE
THE ABILITY TO COMPLETELY COVER THE PATIENTS
BACK WITH TLDS.
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BEFORE BEGINNING THIS STUDY A PROTOCOL WAS
DEVELOPED AND APPROVED BY THE DEPARTMENTS INSTITU
TIONAL REVIEW BOARD
EACH PARTICIPATING HOSPITAL HAS USED OUR IRB
APPROVAL TO SECURE AN EXPEDITED REVIEW FROM
THEIR INTERNAL IRB
EACH PATIENT IS GIVEN AN INFORMED CONSENT
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DR. LEWIS FROM INTERNATIONAL SPECIALTY PRODUCTS
COLLABORATED WITH US TO PROVIDE A METHOD
TO SURVEY THE ACTUAL PEAK SKIN DOSE
THE DOSIMETRY WAS PERFORMED USING A WIDE-AREA
FILM DOSIMETER CALLED GAFCHROMIC XR FILM
80 MEASUREMENTS HAVE NOW BEEN PERFORMED WITH
ANOTHER 40 CURRENTLY UNDERWAY.
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THE FILM DOSIMETER PROVIDES A DOSE DISTRIBUTION
OR MAPPING FORMAT THAT WOULD NOT BE AVAILABLE
WHEN UTILIZING TLDS ALONE
FOR THE PATIENTS WHO HAVE BEEN STUDIED SO FAR,
THE MINIMUM DOSE MEASUREMENT HAS BEEN ABOUT 150
RADS WITH A MAXIMUM OF 700 RADS
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100 Rads
200 Rads
700 Rads
400 Rads
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Peak Skin Dose Comparison of Measurement with
GAFCHROMIC? XR film vs. Estimate with DAP
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• Skin dose can only be estimated from DAP values
• DAP seriously under estimates the max peak skin
  dose

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GAFCHROMIC? XR Type R

• Details the dose distribution
• Immediate visualization of patient exposure
  magnitude and location

GAFCHROMIC? XR Type R film - a simple tool for
comprehensive monitoring of patient exposure and
physician training
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A picture is worth a thousand words

• Raises physicians awareness
• Know where to treat a latent skin injury
• Define where to avoid exposure in future
  procedures

GAFCHROMIC? XR Type R film - a simple tool for
comprehensive monitoring of patient exposure and
physician training
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WE BELIEVE THAT DOSE MEASUREMENTS FOR PATIENTS
UNDERGOING INTERVENTIONAL PROCEDURES IS AN AREA
THAT NEEDS TO BE LOOKED AT FURTHER
WE ENCOURAGE ALL FACILITIES TO ESTABLISH
THRESHOLDS FOR INTER- VENTIONAL PROCEDURES SO
THAT, IF THE THRESHOLD IS EXCEEDED IN TERMS OF
FLUOROSCOPY TIME AND/OR IMAGING RUNS, THAT
PATIENT WILL BE MONITORED POST- PROCEDURE FOR THE
EFFECTS OF IONIZING RADIATION
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THANK YOU NYSDOH