Influence of an intentionally induced posterior lens capsule rupture on the real-time intraocular pressure during phacoemulsification in canine ex vivo eyes

Objective To evaluate the changes in the intraocular pressure (IOP) following an intentionally induced posterior lens capsule rupture (PLCR) during phacoemulsification in enucleated canine eyes. Furthermore, to compare the IOPs between different stages of phacoemulsification for two different bottle heights (BH). Procedures Coaxial phacoemulsification was performed using a venturi-based machine at a 60 or 90 cm BH. A pressure transducer, inserted into the anterior chamber through the peripheral cornea, monitored real-time IOP. For one half of the lens, the sculpt-segment removal (SS) was followed by irrigation/aspiration (IA). The PLCR was intentionally created, and the SS and IA were repeated on the residual lens fragments. Results For the 60 cm BH, the mean IOP following the PLCR was significantly higher than before the PLCR during SS (28.30 ± 12.56 and 38.71 ± 9.43 mmHg before and after PLCR, respectively) and IA (42.76 ± 12.46 and 47.88 ± 7.10 mmHg before and after PLCR, respectively) stages (P < 0.001). For the 90 cm BH, the mean IOP following the PLCR was also significantly higher than before the PLCR during SS (33.39 ± 11.09 and 58.17 ± 6.89 mmHg before and after PLCR, respectively) and IA (62.39 ± 12.46 and 72.04 ± 8.59 mmHg before and after PLCR, respectively) stages (P < 0.001). Conclusions The occurrence of a PLCR led to an increase in IOP during both the SS and IA stages. The elevated IOP after the PLCR might be one of the most important factors for ocular tissue damage, as it reduces ocular perfusion. Additionally, the BH should be reduced following PLCR to prevent complications stemming from the raised IOP.