AbstractID: 6664 Title: Patient Skin Dose in Fluoroscopically-Guided Cardiac Catheter Ablation as
Measured by a Portal Film Technique
Purpose: With increasing use of lengthy procedures
for fluoroscopically-guided cardiac catheter ablation,
measurement of skin dose is becoming ever more desirable
for monitoring and reducing patient radiation exposure in
order to avoid potential skin injuries such as reported by
FDA(Radiology 197P:449,1995). For this purpose, we
developed an accurate simple technique using film dosimetry.
Preliminary results are presented on our application of
and experience on using the method in consecutive ablation
procedures.
Methods: Three different types of films were used: Kodak
X-Omat, EC films, and a newly developed Radiochromic film
(by ISP of Wyne, NJ), calibrated for doses up to 50, 150,
and 800 cGy(rad) respectively. Films(singly or stacked
2 to 3 together) were placed on table top with the patient
lying on film pack, exposed to entrance radiation passing
through the patient during the entire procedure, developed
at completion of procedure, and evaluated for dose
distribution.
Results: Skin dose measured for 85 consecutive procedures
varied with procedural and patient-related factors, ranging
from 25 to over 200 cGy(median 100) following fluoro times
5-135 min (median 30). Approximately one-third of the
procedures reached doses approaching 200 cGy. Film
dosimetry documented successful achievement of dose
reduction through conscientious effort (optimizing
operation settings, changing entrance angles, minimizing
fluoro time, etc.) during operation.
Conclusions: These results indicate the need for routine
monitoring of patient skin dose in Electrophysiology lab
ablation procedures and demonstrate easily achievable dose
reductions with our technique.