Optics News

Even though 90% of our toric IOL cases should be within 0.5 D of residual astigmatism, there will be cases in which the outcome is intolerable for the patient and something must be done. The following discussion explains the proper management.

Even though 90% of our toric IOL cases should be within 0.5 D of residual astigmatism, there will be cases in which the outcome is intolerable for the patient and something must be done. The following discussion explains the proper management.

Outcomes following cataract surgery with greater than 90% of patients within 0.5 D of the target spheroequivalent refraction are achieved by less than 1% of surgeons. I give these surgeons an “A” for their results, just like in school. “B” surgeons are 80% to 89%, “C” surgeons from 70% to 79%, “D” surgeons from 60% to 69%, and if you are less than 60%, you are failing. An “A” surgeon uses optical biometry and re-measures axial lengths, usually with immersion, if the eyes differ by more than 0.3 mm or have a poor signal-to-noise ratio; uses a five-variable predictor IOL formula, such as Holladay 2, Olsen 2 or Barrett 2; continually personalizes his lens constant; and measures corneal power using the protocol described below.

Outcomes following cataract surgery with greater than 90% of patients within 0.5 D of the target spheroequivalent refraction are achieved by less than 1% of surgeons. I give these surgeons an “A” for their results, just like in school. “B” surgeons are 80% to 89%, “C” surgeons from 70% to 79%, “D” surgeons from 60% to 69%, and if you are less than 60%, you are failing. An “A” surgeon uses optical biometry and re-measures axial lengths, usually with immersion, if the eyes differ by more than 0.3 mm or have a poor signal-to-noise ratio; uses a five-variable predictor IOL formula, such as Holladay 2, Olsen 2 or Barrett 2; continually personalizes his lens constant; and measures corneal power using the protocol described below.

Contact lens wearers who chose to have LASIK are more satisfied with their vision a year postoperatively and most satisfied after 2 to 3 years, according to a recent study in Ophthalmology.

Proper centration of premium IOLs — diffractive multifocal, moderate to high toric, and aspheric — is critical to achieve the maximum optical performance and to avoid unnecessary symptoms of halos, glare and “waxy vision.” To understand and use the optical principles involved with these complaints, we must review the angles of the eye.

SEATTLE – “With every diopter of increase in myopia, you have an increased risk of ocular pathology,” according to Arthur Back, BOptom, PhD, FAAO.

SEATTLE – Ricardo Torres-Vidal, of the Asociacion para Evitar la Ceguera en Mexico, discussed his study involving the use of PlayStation Portable in the treatment of children with amblyopia, here at the Association for Research in Vision and Ophthalmology meeting.

Toric IOLs provide an excellent means of correcting pre-existing corneal astigmatism with cataract surgery. Current studies have shown that the combined residual astigmatism and the spheroequivalent error must be less than 0.5 D for the patient to be happy with his uncorrected vision. To achieve this goal, there are three fundamental rules that must be observed.

Smart Vision Labs announced that clinical testing results on its SVOne autorefractor were comparable with subjective refraction and an office-based autorefractor when measuring refractive error under cycloplegic and non-cycloplegic conditions in young adults with normal vision, according to a press release.