BSS release volume is greatly affected by torsional phaco
First Author: S.Noguchi JAPAN
To examine how the torsional amplitude, sleeve type, tip type, and IOP settings affect the intraocular perfusion supply.
Using CENTURION®, the weight of BSS PLUS® injected during torsional phaco was measured. The weight of BSS injected from the sleeve was measured accurately for 3 seconds (measured 15 times every 200 msec) by weight scale AD-4212C-300. Four measurements were made at each torsional power (TP) setting, and the average value and standard deviation of the perfusion supply rate were calculated. A bent tip (0.9 mm Mini® 45 ° Kelman®; mini tip) and a semi-circular tip (0.9 mm balanced ABS® 45 °; balanced tip), and a nano sleeve were used, respectively. The perfusion rate was measured at IOP20mmHg and IOP40mmHg.
In the balanced tip + nano sleeve, the perfusion rate increased 1.18 to 1.27 times at IOP 40 mmHg when compared to IOP 20 mmHg. In both IOPs, perfusion decreased with TP. In the balanced tip + ultra sleeve, there was no significant decrease in perfusion rate with TP in both IOPs. Mini tips + nano sleeves were greatly affected by TP, and perfusion decreased. In the setting of IOP40 mmHg, an increase in perfusion of 1.28 to 1.42 times is recognized. In the mini tip + ultra sleeve, The flow rate decreased more than TP80%. In IOP40 mmHg, a flow rate of 1.39 to 1.58 times was recognized compared to that in IOP20 mmHg.
Except for the balanced tip + ultra sleeve setting, all perfusion flow tended to decrease due to the influence of TP. In particular, in the case of TP with TP 80% or more, the decrease of perfusion rate was remarkable. This suggests the anterior chamber is likely to become unstable in cases requiring TP high power.