Post-occlusion surge parameters during <i>ex vivo</i> phacoemulsification with a new method of adaptive infusion control

Abstract

A new method of adaptive control of infusion during phacoemulsification (PE) based on the Optimed Profi (Optimedservice) surgical system was developed, allowing calculation of the predicted volume of post-occlusion surge (POS) by monitoring aspiration and infusion flow rates. Purpose. To compare POS amplitude, predicted and actual volumes of POS during experimental ex vivo PE on cadaveric porcine eyes, between Optimed Profi and Centurion Vision surgical systems. Material and methods. For two experimental PE series of 10 operations on porcine eyes, the mean POS amplitude (mm Hg) was measured using a pressure sensor in the anterior eye chamber. Predicted and actual POS volumes were assessed using a non-contact aspiration-line flowmeter sensor by varying aspiration flow rate depending on the phaco needle patency. The parameters were compared between the series using the Student t-test. Results. The mean POS amplitude during PE by Optimed Profi and Centurion Vision System was 12.10 ± 0.21 and 13.3 ± 0.3 mm Hg, respectively (p < 0.001). The mean value of the predicted POS volume during PE by Optimed Profi and Centurion Centurion Vision System was 136.80 ± 9.59 and 146.00 ± 9.46 μm, respectively (p > 0.01). The mean value of the actual POS volume during PE by Optimed Profi and Centurion Vision System was 135.30 ± 4.97 and 158.50 ± 8.63 μm, respectively (p < 0.01). Conclusion. The lower values of POS amplitude and predicted and actual volumes of POS in the series using the new method of adaptive infusion control may indicate a better hydrodynamic stability in experimental PE.

Keywords

• post-occlusion surge
• phacoemulsification
• adaptive infusion control
• flow rate