Purpose: To compare the corticocapsular separation created by viscodissection and by hydrodissection using Miyake-Apple video-photographic analysis.
Setting: University-based center.
Methods: Fourteen cadaver eyes were randomized to hydrodissection (Group 1, n=7) or viscodissection (Group 2, n=7). Twelve eyes were prepared for Miyake-Apple viewing. One eye in each group was prepared to simulate a closed chamber. On Miyake-Apple viewing, corticocapsular separation was graded from 0 to 3 after hydrodissection/viscodissection and at the sculpting, nuclear division, and early and late fragment removal stages. The surgeon's subjective impression of the mechanical cushion effect was noted. Histopathology of the capsular bag was performed in 4 eyes in each group to determine the amount of residual lens epithelial cells (LECs).
Results: More space was created and maintained between the capsule and cortex in Group 2 than in Group 1. The mean scores in Groups 1 and 2 were endpoint of hydrodissection/viscodissection 1.92+/-0.38 and 2.58+/-0.38, respectively (P=.05); sculpting, 1.6+/-0.42 and 2.3+/-0.45, respectively (P=.05); nuclear division, 0.9+/-0.42 and 1.5+/-0.35, respectively (P=.13); early fragment removal, 0.6+/-0.22 and 1.0+/-0, respectively (P=.04); and late fragment removal, 0.1+/-0.22 and 0.4+/-0.22, respectively (P=.17). Although only early fragment removal achieved statistical significance, the surgeon's impression confirmed greater cushion effect with viscodissection. Residual LECs in the 2 groups were comparable.
Conclusion: Viscodissection as an adjunct to hydrodissection created and maintained greater corticocapsular separation than hydrodissection alone during phacoemulsification.