Abstract
Abstract: :
Purpose: To determine the effect of thrombocytopenia on the treatment outcomes after diode laser photocoagulation in threshold ROP. Methods: A retrospective chart review of 23 premature infants (46 eyes) treated with indirect diode laser photocoagulation for threshold ROP was done. Infants were divided into two subsets based on normal (>= 150,000) or below normal (< 150,000) platelet counts. An analysis of the outcome of laser treatment has been previously presented. A subset analysis in the thrombocytopenic and non–thrombocytopenic groups was performed here to evaluate the impact of the presence and/or duration of vitreous hemorrhage after laser treatment on rates of progression of ROP to retinal detachment. Results: A review of the characteristics of the two groups and their outcomes which has been already presented is summarized below. 37 eyes (80%) regressed and 9 (20%) progressed to retinal detachment (RD). The non–thrombocytopenic group included 30 eyes of which 26 eyes regressed (86.5%), while 4 eyes progressed to RD (13.5%). The thrombocytopenic group included 16 eyes of which 11 eyes regressed (69%), while 5 eyes progressed to RD (31%). Thus a statistically significant percentage of thrombocytopenic infants (31%) progressed to RD compared to non–thrombocytopenic infants (13.5%) after laser treatment (p=0.0062). A further subset analysis assessing the impact of presence and/or duration of vitreous hemorrhage on ROP progression to RD was performed here. In the 9 eyes which progressed to RD, 7 (77.8%) had vitreous hemorrhage. By comparison, of the 37 eyes which regressed, only 8 eyes (21.6%) had vitreous hemorrhage (p=0.0029). In the 5 eyes of thrombocytopenic patients which progressed to RD, 4 eyes (80%) had post–laser vitreous hemorrhage. By comparison, in the 4 eyes of non–thrombocytopenic patients which progressed to RD, 3 had vitreous hemorrhage (75%; p = 1.000). However, the mean duration of vitreous hemorrhage in the 4 eyes in the thrombocytopenic group which progressed to RD was 60 days as compared to 15 days in the non–thrombocytopenic group (n = 3, p = 0.00004). Conclusions: We propose that persistent vitreous hemorrhage may occur due to low platelet count during the post–laser period. Therefore correction of thrombocytopenia prior to laser treatment may prevent occurrence of vitreous hemorrhage and subsequent disease progression in these cases.
Keywords: retinopathy of prematurity