The Level of Intercellular Adhesive Molecule-1 in Proliferative Diabetic Retinopathy. Effect of Laser Photocoagulation and Intravitreal BevacizumabÂ

Purpose: To identify the level of vitreous intercellular adhesive molecule-1 (ICAM-1) in proliferative diabetic retinopathy (PDR) patients treated by laser photocoagulation (LP) and intravitreal bevacizumab (IVB). Methods: A cross-sectional study was conducted during 2015-2016. In total, 65 consecutive PDR patients who underwent single/multiple-session LP or IVB therapy were enrolled in this study. ICAM-I was extracted from undiluted vitreous fluid via vitrectomy and measured by enzyme-linked immunosorbent assay (ELISA). Results: Of 65 subjects, 13 were treated with IVB, 10 with single LP (sLP), and 9 with multiple-session LP (mLP). The remaining patients who only underwent vitrectomy served as the control group (n = 33). There were 45 (69.2%) female and 20 (30.8%) male patients with a mean age of 51 years. We found an increase of ICAM-1 level in PDR patients treated with IVB and mLP, yet there was no statistically significant difference between these therapy groups (P > 0.05). HbA1c level and insulin usage had no significant association with ICAM-1 level (P = 0.54 and P = 0.52, respectively). On the contrary, there was an association between ICAM-1 level and the duration of diabetic mellitus (P < 0.05). Conclusions: IVB injection 1-2 weeks prior to vitrectomy was not enough to decrease the level of vitreous ICAM-1, while mLP might induce the increase level of vitreous ICAM-1.