Accurate assessment of tumor size is crucial in the treatment of choroidal melanoma. Digital fundus photographic systems can create a montage that clearly documents the tumor margins. These images can be used to measure tumor maximal linear dimension (MLD). This study evaluates the potential value of a digital imaging system compared with echography in measuring the MLD of choroidal melanoma.Methods:
Echographic measurements were performed in a standardized fashion following Collaborative Ocular Melanoma Study (COMS) methods. For photographic measurements, the tumor margin was outlined with an electronic pen and the MLD were calculated by software (ANKA-ProView, Topcon Medical Systems, Paramus, NJ).Results:
The mean MLD before I-125 brachytherapy was 9.32 mm by echography and 10.57 mm by digital photography analysis. This difference was statistically significant (P < 0.001). The 2 measurements of MLD agreed within 1.1 mm for 11 eyes (52%) and 2.2 mm for 20 eyes (95%). Digital photographic analysis estimated a larger MLD in 19 of the 21 eyes compared with echography.Conclusion:
This discrepancy likely results from the photographic measurement more accurately assessing the flat portion of the tumor. Digital photographic analysis may allow clinicians to determine the MLD of tumors more accurately than echography. This could increase the rate of successful treatment with brachytherapy.