Introduction The increasing complexity involved in procedures requiring fluoroscopy, such as ERCP, results in heightened screening times with attendant radiation exposure during these procedures. Deterministic effects are directly correlated with radiation dose and can be adjusted for during fluoroscopy but stochastic effects such as cataract due to ocular exposure are more difficult to determine. The International Commission of on Radiation Protection (ICRP) recommends a total body radiation threshold of no greater than 50mSv/year with an ocular dose limit of 20mSv/year.
Method A literature search was performed on PubMed to identify studies involving ERCP in which radiation exposure was reported. Demographic data and data on fluoroscopy time and ocular exposure were extracted. A fixed and random effects meta-analyses was conducted.
Results 22 studies (7750 procedures) were identified, of which 8 studies (739 procedures) contained data on ocular exposure. The mean screening time per procedure was 3.9 min with a mean of 3 images captured per procedure. The mean ocular exposure per procedure was 0.26mSv. On fixed effects meta-analysis, the point estimate for ocular exposure per procedure was 0.017 (95% CI 0.015–0.018)mSv (Q 850.49, I2 98.4, p<0.001). On random effects meta-analysis, ocular exposure was 0.092 (0.075–0.108)mSv (p<0.001). On comparing these point estimates to the ocular dose limit of 20mSv/year, 1177 ERCPs (using fixed effects data) and 217 ERCPs (using random effects data) with a mean of 697 ERCPs per individual per year could deliver an ocular radiation dose equivalent to this dose limit (Table 1). The wide range is reflective of the heterogeneity and variability in the case mix, complexity, operator technique and the type of fluoroscopy system used in the published studies.
Conclusion Ocular radiation exposures are generally low during ERCP but operators performing high volumes (>200 per year) and complex ERCPs involving prolonged fluoroscopy need to exercise caution in relation to ocular exposure. Ocular shielding using lead-lined glasses may be reasonable in this group.
Disclosure of Interest None Declared