Purchase this article with an account.
S Lee, TC Lee, MJ Dinkin, M Ober, K Beaverson, DH Abramson; Laser Scar Progression in Children Treated with Transpupillary Thermotherapy for Retinoblastoma . Invest. Ophthalmol. Vis. Sci. 2002;43(13):2594.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: Although it is recognized that photocoagulation scars increase in size over time, little information is available about transpupillary thermotherapy (TTT) scars in growing infant eyes. Since TTT is used primarily in the posterior pole for children with retinoblastoma, information about the nature of this growth may be important in planning future treatments because if tumor scars near the fovea expand, vision might be compromised. Methods: We performed a retrospective review of 180 patients diagnosed with retinoblastoma who had photodocumentation of their tumors and treatments utilizing the Retcam unit. To be included in the study, the treated tumors required minimum of one year's follow-up. Exclusion criteria were as follows: 1) Tumors anterior to the equator 2) Tumors that required retreatment with TTT, cryotherapy, brachytherapy, or enucleation prior to 12 month follow-up 3) Any scars that coalesced to adjacent scars in the 12 months follow-up period. The following parameters were measured using the Retcam unit: Optic nerve (ON) size, linear distance from ON to nearest scar edge (D1), linear distance from ON to furthest scar edge (D2), and area of scar (AS). Measurements were taken by two independent observers and the results were averaged. Results: 13 tumors from 8 eyes (8 patients) were measured. 2 were male and 6 were female. Mean age at treatment was 20.5 weeks old (1 to 51 weeks). The mean increase in the linear dimension of the scar was 0.44mm (-0.28 to 1.58mm) at 6 months and 0.46mm (-0.33 to 1.58mm) by 12 months. The maximum growth in linear dimension of any scar was 1.78mm at 11 months. The mean percentage increase in the linear dimension of the scars was 24.86% (-12.92 to 81.89%) by 12 months. The mean increase in the area of the scar was 50.72% (-10.86 to 163.44%) at 12 months. The increase in the scar size post-TTT occurs primarily in the first 6 months (96.18% of total increase). Conclusion: Our study shows that most post-TTT treatment scars (11/13 scars) increase in size. No scars increased in linear dimension greater than 1.78mm in our study population. Based on this data, macular tumors are amenable to treatment with TTT provided that sensitive structures are greater than one disc diameter away.
This PDF is available to Subscribers Only