Abstract
Purpose: :
To compare ultrasound energy used after laser lens fragmentation with ultrasound energy used after conventional phacoemulsification in nuclear cataract.
Methods: :
Patients presenting for cataract surgery were recruited on to this study after signing the IRB approved informed consent document. The eye with worse acuity underwent laser lens fragmentation either with or without laser anterior capsulotomy (test group). Where the contralateral eye required cataract surgery, conventional phacoemulsification without laser lens fragmentation was used. (control group) The primary outcome measure was the amount of ultrasound energy used during the procedure reported as Cumulative Dissipated Energy (CDE) as displayed by the Alcon Infiniti Device, analyzed by cataract grade.
Results: :
There was a total of 85 eyes that underwent laser lens fragmentation and 53 contralateral eyes that underwent conventional phacoemulsification. Overall mean (SD) CDE was 11.38 (14.93) for the laser treated eyes and 14.04 (16.04) for the standard phacoemulsification eyes, a 19% reduction (p=0.02). For lower grade cataract the reductions were higher than for the higher grade cataracts. For Grade 1 nuclear cataract, the Mean (SD) CDE was 0.00 (0.00) in the test group and 4.38 (2.38) in the control group, a reduction of 100% (p=0.006). For Grade 2 nuclear cataract the Mean (SD) CDE was 2.98 (3.98) for the test group and 8.20 (6.13) in the control group, a reduction of 64% (p<0.001). For Grade 3, the values were 9.27 (9.43) and 15.24 (12.95) for test and control groups respectively, a reduction of 39% and for Grade 4 24.04 (18.75) and 41.18 (24.68), a reduction of 42%. In the latter cases the reduction was only significant at the 90% level.
Conclusions: :
Laser lens fragmentation improves the ease with which nuclear cataract can be removed during cataract surgery. An overall reduction in the amount of ultrasound energy used after laser lens fragmentation compared to conventional phacoemulsification was 19% with lower grade cataracts requiring little or no ultrasound energy. In harder cataracts, while ultrasound energy was still required, the amount used was reduced by approximately 40%.
Clinical Trial: :
http://www.clinicaltrials.gov NCT01062464
Keywords: cataract • laser