Pilot Study of the Delivery of Microcollimated Pars Plana External Beam Radiation in Porcine Eyes: 270-Day Analysis
Retinal, RPE, and choroidal histological changes in all dosage groups through the target lesion site. (a) Control, (b) 16 Gy, and (c) 24 Gy demonstrate no discernible retinal, RPE, or choroidal changes. (d) 42 Gy shows a broad based lesion with photoreceptor, outer nuclear layer atrophy (arrow), and mild to moderate RPE damage (triangle). (e) 60 Gy shows a more impressive lesion with loss of photoreceptors and outer nuclear layer attenuation (arrow) and moderate RPE attenuation (triangle). (f) 90 Gy demonstrates distinct areas of damage involving the entire thickness of the retina (arrow) with RPE and choroidal disruption (triangle).