2.10. Indirect diode laser photocoagulation for ROP

Laser therapies are carried out in the Neonatology Units, under sedation. Prior laser treatment, pupil dilation is achieved with a mixture of tropicamide 0.5% and phenylephrine 2.5%. The eyes are maintained open with a lid speculum throughout the procedure, the retina is visualized with a +20 or +28 diopter lens and the peripheral retina is accessed with a scleral indentor.

Diode laser has an infrared emission of 810 nm, which is delivered transpupillary. Usually, the following laser parameters are used: 200 microns laser spot, with 200 ms duration and power between 100 and 300 mW, according to the retinal reaction. Laser spots are applied on all the surface of the non-vascular retina, from the anterior margin of the ridge to the ora serrata, in a confluent manner, with no space between them.

Adverse events related to laser treatment were cited in the literature: anterior uveitis, cataract, vitreous hemorrhage, retinal detachment [7]. Anterior uveitis was rarely identified in cases that required extensive laser photocoagulation, such as aggressive posterior-ROP [2]. The risk of cataract development is very low, especially when using the infrared laser which is absorbed deep into the choroid and not in the crystalline lens [2, 7]. Vitreous hemorrhage and retinal detachment represent rather a failure of laser to stop ROP progression than a complication by itself [2].
