Biomedical subjects
Publications and source records attributed to Paul H Ernest.
A 69-year-old man who had uneventful bilateral cataract surgery with visual acuity of 20/15 without correction presented with severe dysphotopsia. Treatment with brimonidine (Alphagan) or pilocarpine did not resolve the symptoms. A multipiece silicone intraocular lens was piggybacked into the sulcus, and the patient no longer reported dysphotopsia.
PURPOSE: To compare the light transmittance of 4 currently marketed intraocular lenses (IOLs) with that of the new AcrySof Natural IOL (Alcon Laboratories, Inc.), which is designed to mimic the light-attenuating characteristics of the human crystalline lens. SETTING: Research laboratory, Alcon Research, Ltd., Fort Worth, Texas, USA. METHODS: Light-transmission spectra of 4 commonly implanted IOLs were compared with the spectrum of the AcrySof Natural IOL (model SN60AT). RESULTS: While the 4 other foldable IOLs transmitted nearly 100% (near 0% absorption) of the light in the 400 to 500 nm (blue-light) region, the AcrySof Natural IOL absorbed a significant portion of blue light. Comparison of the spectrum of the AcrySof Natural IOL with the spectrum of human crystalline lenses of various ages showed that the AcrySof Natural lens closely mimics the light-attenuating characteristics of the human crystalline lens. CONCLUSIONS: The AcrySof Natural IOL provides a transmission spectrum more like that of a human crystalline lens than do other commonly implanted foldable IOLs. The Natural IOL reduces ultraviolet and blue-light exposure to the retina, mimicking the filtering normally provided by the human crystalline lens.
PURPOSE: To compare the incidence and severity of posterior capsule opacification (PCO) and neodymium:YAG (Nd:YAG) capsulotomy rates between AcrySof(R) MA30BA acrylic (Alcon) and PhacoFlex(R) II SI-40NB silicone (AMO) intraocular lenses (IOLs). SETTING: Outpatient Cataract Surgery Center, TLC Eyecare and Laser Center, Jackson, Michigan, USA. METHODS: AcrySof and PhacoFlex II IOLs were implanted in fellow eyes of 156 patients requiring bilateral cataract extraction. The patients were followed for a mean of approximately 3 years for the incidence and severity of PCO and the Nd:YAG capsulotomy rates. RESULTS: Of the 63 eyes that were free of PCO throughout the study, 42 had the AcrySof IOL and 21 had the PhacoFlex II IOL. Of eyes that developed PCO, the mean severity in the AcrySof group was 16% less than that in the PhacoFlex II group. Of the 50 eyes that had an Nd:YAG capsulotomy, 17 were in the AcrySof group and 33 were in the PhacoFlex II group. All differences between groups were statistically significant (P<.05). CONCLUSION: The AcrySof MA30BA IOL was associated with less PCO proliferation and thus fewer Nd:YAG laser posterior capsulotomies than the PhacoFlex II SI-40NB IOL.
A 64-year old man had noncontact holmium:YAG (Ho:YAG) laser thermal keratoplasty (LTK) performed in the left eye on March 10, 1998, and in the right eye on January 11, 1999. The patient achieved 1.3 diopters (D) and 1.4 D of corneal steepening in the right and left eye, respectively, which was the desired amount as his refractive error before Ho:YAG LTK was low. At the 3-month postoperative examination of the left eye, cortical cataracts were observed in both eyes. Approximately 1 year later, bilateral cataract extraction was recommended because of patient-reported decreased vision at distance and near and difficulty with vision in the presence of glare. Cataract surgery and intraocular lens (IOL) implantation was performed in both eyes in August 1999 using the keratotomy readings taken after noncontact Ho:YAG LTK to calculate IOL power. Although slight flattening of the cornea occurred after cataract extraction, the refractive outcomes achieved by noncontact Ho:YAG LTK were generally preserved.