Damage mechanisms of pico- and femtosecond laser retinal lesions as viewed by electron microscopy

Retinal lesions produced by ultrashort laser pulses in the pico- and femtosecond range were examined by electron microscopy. Retinal pigment epithelial (RPE) cells that contained fractured and striated melanosomes typically exhibited severe damage to the other components of the cell. However, having observed RPE cell damage without coincident fractured melanosomes, it is thought that melanosome fracture itself is not responsible for the damage that occurs within the RPE cell. Nevertheless, the percentage of melanosomes fractured per lesion seems to parallel the severity of damage within that lesion site. No trend existed between percentage of melanosomes fractured and the peak power of laser delivery. However, with decreasing laser pulsewidth, there was a decrease in the percentage of melanosomes showing fracture.

Duke Scholars

Author Cynthia Ann Toth Ophthalmology, Vitreoretinal Diseases & Surgery