Comparison Between the Wong Incision and Stromal Hydration of Corneal Incisions in Phacoemulsification
Raymond Nelson Regalado, MD, Jay Marianito Vicencio, MD, Lee Verzosa, MD, and Ruben Lim Bon Siong, MD
Objective
To determine the efficacy of the Wong incision in providing wound seal compared to stromal wall hydration in clear cornea phacoemulsification in cadaveric porcine eyes.
Methods
This was an in vitro comparative experimental study using ten porcine eyes. All eyes were randomly assigned to the stromal wall hydration (control) or the Wong incision group (experimental). A side port was made and the anterior chamber formed with viscoelastic device. The main incision was made 180 degrees away. In the experimental group, a Wong incision was made first anterior to the main incision. Phacoemulsification surgery with IOL insertion was simulated. The main incision was sealed by hydration. The anterior chamber (AC) was infused with balanced salt solution (BSS) through an AC maintainer and leakage of fluid from the main incision was assessed. Samples from the AC were taken before and after tryphan blue drip and were sent for analysis by UV spectrophotometry. Trypan blue was dripped over the main incision and the whole eyeball was sent for histopathology.
Results
There was a significant increase in density from the pre-dye to the post-dye AC samples of the control (0.0052 to 0.0074, p=0.01) and the experimental groups (0.0076 to 0.0094, p=0.02), although the final samples showed an optical density comparable to pure BSS, indicating that there was no significant amount of trypan blue detected in both groups. On histology, trypan blue staining was not seen in the incision tracts of both groups. After infusing the AC with BSS, there was outward wound leakage in all eyes of the control group and none in the experimental group.
Conclusions
The Wong incision was as effective as the lateral stromal wall hydration in preventing fluid influx. Furthermore, the Wong incision showed a more stable wound seal against outward wound leakage in an in-vitro porcine model of clear corneal phacoemulsification.
Keywords:Wong incision, supraincisional hydration pocket, stromal hydration, clear corneal incision, phacoemulsification, wound leak