A Morphometric Comparison of the Acute Rabbit and Pig Corneal Response to 1540 nm Laser Light Following Ex Vivo Exposure

摘要

Single pulse, 1540 nm laser light with a pulse width of 1 microsecond altered the morphologic appearance of explant rabbit and pig corneas following ex vivo exposure. Using digital images of the post-exposure corneas projected onto a measuring grid, we could accurately locate the relative position of the circular laser lesion the the embedded tissue. This allowed us to section through the lesion with micrometer precision and accurately resolve the inside edge, middle and outside edge of the laser lesion. All tissue sections used for morphometric analysis were taken through the middle of the lesion. Several features of the response to laser exposure may reflect species-specific tissue differences. The rabbit corneal epithelium showed a homogeneous coagulative necrosis with a distinct demarcation between necrotic and normal epithelium. The pig epithelium also showed a distinct demarcation between necrotic and normal epithelium, however, there were several remarkable differences in the tissue response between the two species including coagulative necrosis pattern and nuclear morphology. These changes suggested a different and less severe response of the pig epithelium to the laser light when compared to the rabbit epithelium.