Hydroxyl free radical production during torsional phacoemulsification.
OBJECTIVE
To quantitate free radical generation during phacoemulsification using an ultrasonic phacoemulsification device that includes a torsional mode and evaluate tip designs specific to the torsional mode.


METHODS
Chemistry and Biochemistry Department, Utah State University, Logan, Utah, USA.


METHODS
Experimental study.


METHODS
Experiments were performed using the Infiniti Vision System and OZil handpiece. Hydroxyl radical concentrations in the aspirated irrigation solution during torsional phacoemulsification were quantitated as nanomolar malondialdehyde (nM MDA) and determined spectrophotometrically using the deoxyribose assay.


RESULTS
The mean free radical production during phacoemulsification with torsional modality at 100% amplitude was 30.1 nM MDA ± 5.1 (SD) using a 0.9 mm 45-degree Kelman tapered ABS tip. With other tip designs intended for use with the torsional modality, free radical production was further reduced when fitted with the 0.9 mm 45-degree Kelman mini-flared ABS tip (13.2 ± 5.6 nM MDA) or the 0.9 mm 45-degree OZil-12 mini-flared ABS tip (14.3 ± 6.7 nM MDA). Although the measurements resulting from the use of the latter 2 tips were not statistically significantly different (P ≈ .25), they were different from those of the tapered tip (P<.0001).


CONCLUSIONS
The MDA concentration in the aspirated irrigation solution using the torsional modality was approximately one half that reported for the handpiece's longitudinal modality in a previous study using the same bent-tip design (Kelman tapered, P<.0001). The level of MDA was further reduced approximately one half with torsional-specific tips.
Chemistry and Biochemistry Department, Utah State University, Logan, Utah 84322-0300, USA. sdaust@cc.usu.edu
Steven D
SD
Aust
Thomas
T
Hebdon
Jordan
J
Humbert
Ramon
R
Dimalanta
D000085:Acetates / Q000378:metabolism*; D004322:Drainage / Q000379:methods; D004338:Drug Combinations; D017665:Hydroxyl Radical / Q000378:metabolism*; D008315:Malondialdehyde / Q000032:analysis; D008903:Minerals / Q000378:metabolism*; D018918:Phacoemulsification / Q000295:instrumentation*; D012965:Sodium Chloride / Q000378:metabolism*; D013053:Spectrophotometry; D007507:Therapeutic Irrigation
D000085:Acetates; C030660:BSS solution; D004338:Drug Combinations; D008903:Minerals; D017665:Hydroxyl Radical; D012965:Sodium Chloride; D008315:Malondialdehyde