Abstract
Purpose: :
To evaluate a variety of treatment interventions for choroidal neovascularization (CNV) in the non-human primate from pulsed Nd-YAG laser injury as this class of laser is commonly deployed in a multitude of military and commercial laser systems. In contrast to lesions produced by continuous laser energy, pulsed laser lesions are frequently associated with significant retinal disruption and vitreous hemorrhage. For this reason, the natural history of CNV from pulsed laser injury may differ from subretinal neovascularization produced by continuous laser exposure.
Methods: :
Utilizing optimal parameters to produce CNV in cynomologous monkeys (macaca fasicularis) photodynamic therapy with verteporphin was compared to treatment with anti-inflammatory therapy using steroid and non-steroidal drug (NSAID) treatment. We also anticipate comparison of PDT to vascular endothelial growth factor inhibitors. Fluorescein angiography, high resolution optical coherence tomography (OCT), and histopathology were employed to evaluate the effectiveness of treatment interventions.
Results: :
PDT with standard application of 83 seconds of 689nm laser light resulted in consistent ablation of CNV. Such treatment also appeared to reduce subretinal scarring and attenuation of overlying neurosensory retina whereas treatment with intracameral steroid medication (triamcinolone) or parenteral non-steroidal medication (ketorolac) did not appear to have a significant effect on resolution of CNV. Comparison of mean values of photoreceptor signal intensity on OCT showed enhanced preservation of this layer with PDT versus steroid and NSAID medication.
Conclusions: :
CNV from pulsed Nd-YAG laser energy responds favorably to PDT versus treatment with steroid or NSAID drug therapy alone. In addition, PDT appears to enhance preservation of photoreceptor elements in the setting of CNV from pulsed Nd-YAG laser injury.
Keywords: choroid: neovascularization • photodynamic therapy • corticosteroids