Effect of Artificial Tears on Preoperative Keratometry and Refractive Precision in Cataract Surgery

Christian Nilsen,1 Morten Gundersen,1 Per Graae Jensen,1 Kjell Gunnar Gundersen,1 Richard Potvin,2 Øygunn A Utheim,3– 5 Bjørn Gjerdrum1 1Ifocus Eye Clinic, Haugesund, Norway; 2Science in Vision, Frisco, TX, USA; 3Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway; 4Department of Ophthalmology, Oslo University Hospital, Oslo, Norway; 5The Norwegian Dry Eye Clinic, Oslo, NorwayCorrespondence: Christian Nilsen, Ifocus Eye Clinic, Strandgaten 203, Bergen, 5004, Norway, Tel +47 97189598, Email [email protected]: The primary objective was to investigate if treatment with artificial tears affected the variability of keratometry measurements for subjects with dry eyes prior to cataract surgery. The secondary objectives were to investigate whether treatment with artificial tears improved refractive precision and whether subjects with non-dry eyes had better refractive precision than subjects with dry eyes.Design: Prospective randomized controlled trial with three arms.Patients and methods: Dry eye diagnostics according to DEWS II were performed, and subjects with dry eyes were randomized to no treatment (group A1) or treatment with artificial tears two weeks prior to cataract surgery (group A2), with the third group (Group B, non-dry eyes) as a control. Keratometry was performed twice at baseline and twice after two weeks at the time of cataract surgery with three different optical biometers. The change in mean variability of keratometry (average K and magnitude of vector differences) and percentages of outliers after two weeks versus baseline were compared for group A2. The refractive and astigmatism prediction errors were calculated eight weeks after cataract surgery and compared for all three groups.Results: One hundred thirty-one subjects were available for analysis. There was no statistically significant difference in the mean variability of keratometry or percentages of outliers for group A2 from baseline to the time of cataract surgery. There was no statistically significant difference in refractive precision (absolute error and astigmatism prediction error) between any groups.Conclusion: Subjects with dry eyes (treated and non-treated) achieved the same refractive precision and percentages of outliers as subjects with non-dry eyes. Treatment with artificial tears for two weeks appeared inadequate to significantly affect variability in biometric measurements for patients with dry eyes prior to cataract surgery. DEWS II criteria for DED may not be optimal in a cataract setting.Keywords: Cataract surgery, non-invasive keratography tear break-up time, ocular surface staining, osmolarity, artificial tear

Optic disc classification by the Heidelberg Retina Tomograph and by physicians with varying experience of glaucoma

PurposeTo compare the diagnostic accuracy of the Heidelberg Retina Tomograph's (HRT) Moorfields regression analysis (MRA) and glaucoma probability score (GPS) with that of subjective grading of optic disc photographs performed by ophthalmologists with varying experience of glaucoma and by ophthalmology residents.MethodsDigitized disc photographs and HRT images from 97 glaucoma patients with visual field defects and 138 healthy individuals were classified as either within normal limits (WNL), borderline (BL), or outside normal limits (ONL). Sensitivity and specificity were compared for MRA, GPS, and the physicians. Analyses were also made according to disc size and for advanced visual field loss.ResultsForty-five physicians participated. When BL results were regarded as normal, sensitivity was significantly higher (P<5%) for both MRA and GPS compared with the average physician, 87%, 79%, and 62%, respectively. Specificity ranged from 86% for MRA to 97% for general ophthalmologists, but the differences were not significant. In eyes with small discs, sensitivity was 75% for MRA, 60% for the average doctor, and 25% for GPS; in eyes with large discs, sensitivity was 100% for both GPS and MRA, but only 68% for physicians.ConclusionOur results suggest that sensitivity of MRA is superior to that of the average physician, but not that of glaucoma experts. MRA correctly classified all eyes with advanced glaucoma and showed the best sensitivity in eyes with small optic discs

The influence of semantic and phonological factors on syntactic decisions: An event-related brain potential study

During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event-related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors

Clinical outcomes with toric intraocular lenses planned using an optical low coherence reflectometry ocular biometer with a new toric calculator

Kjell G Gundersen,1 Richard Potvin21IFocus &Oslash;yeklinikk AS, Haugesund, Norway; 2Science in Vision, Akron, NY,&nbsp;USAPurpose: To prospectively evaluate postoperative clinical outcomes with implantation of toric intraocular lenses (IOLs) using preoperative keratometry from an optical low coherence reflectometry (OLCR) ocular biometer (Lenstar&reg; LS900) and the built-in Barrett toric calculator.Patients and methods: A prospective observational study recruited one or both eyes of subjects who underwent uncomplicated cataract surgery with toric IOL implantation using OLCR biometery data and the Barrett toric IOL calculator for toric IOL planning. Data were collected at the preoperative, operative, 1-day and 2-month postoperative visits. The primary outcome measure was the manifest refractive astigmatism magnitude at 2 months. The secondary outcome measures included the manifest refraction, corneal keratometry, and distance visual acuity (corrected and uncorrected). The results obtained with the Barrett toric calculator were compared with simulated results based on the toric calculators designed for the IOLs being used.Results: Data from 98 eyes of 54 subjects were available for analysis. In the 74 eyes with postoperative lens orientation as planned, and sufficient IOL cylinder power to correct subjects&rsquo; measured astigmatism, 77% of eyes (57/74) had 0.5 diopter (D) or less refractive cylinder 2&nbsp;months postoperatively, while 89% (66/74) had 0.75 D or less. Simulated results after adjusting actual IOL orientation to the planned orientation suggested that the Barrett calculator would result in postoperative residual astigmatism about 0.2 D lower than that expected with standard calculators.Conclusion: Use of the Barrett toric calculator with biometry data from the Lenstar LS900 biometer for toric IOL planning in a clinical setting resulted in significantly lower levels of residual refractive cylinder than might be expected with standard calculators. Postoperative lens orientation and variability in the measurement of corneal astigmatism pre- and postoperatively appear to be important limiting factors in toric IOL outcomes.Keywords: Lenstar, keratometry, cataract surgery, astigmatism, cylinder, toric IO

Comparison of visual outcomes after implantation of diffractive trifocal toric intraocular lens and a diffractive apodized bifocal toric intraocular lens

Kjell Gunnar Gundersen,1 Rick Potvin2 1IFocus &Oslash;yeklinikk AS, Haugesund, Norway; 2Science in Vision, Akron, NY,&nbsp;USA Purpose: The aim of this study was to compare a new diffractive trifocal toric lens with an apodized diffractive bifocal toric lens in terms of refractive and visual acuity (VA) outcomes, including low-contrast VA (LCVA), as well as the patient&rsquo;s visual function 3&nbsp;months after implantation. Patients and methods: This is a randomized prospective study involving bilateral implantation of a trifocal toric or a bifocal toric lens. At 3&nbsp;months postoperatively, the subject&rsquo;s vision was tested both uncorrected and with his/her best distance correction at: distance (4&nbsp;m), intermediate (63&nbsp;cm), and near (40&nbsp;cm). Binocular defocus curves were measured with no correction and with the subject&rsquo;s best distance correction in place. Quality of vision was measured using the National Eye Institute Visual Function Questionnaire. Results: A total of 22 patients were enrolled (eleven in each group). There was no statistically significant difference in the absolute change in measured rotation between 1&nbsp;month and 3&nbsp;months postoperatively between the two intraocular lens (IOL) groups (P=0.98). At 3&nbsp;months, the postoperative refraction and distance VA by eye were similar between groups. There was no statistically significant difference in the measured LCVA between groups (P=0.39). The defocus curve showed that at 67&nbsp;cm, the trifocal toric lens had statistically significantly better VA when compared to the bifocal toric lens. There were no statistically significant differences by group for any of the National Eye Institute Visual Function Questionnaire scores (P&gt;0.26 in all cases). Conclusion: The trifocal toric IOL improved the intermediate vision without negatively impacting visual function and distance, near, or low-contrast VA when compared to a bifocal toric IOL. The toric component of the trifocal lens effectively reduced astigmatism and provided good rotational stability. Keywords: FineVision, ReSTOR, astigmatism, multifocal, defocus curve, contrast sensitivit

Comparison of visual outcomes and subjective visual quality after bilateral implantation of a diffractive trifocal intraocular lens and blended implantation of apodized diffractive bifocal intraocular lenses

Kjell G Gundersen,1 Rick Potvin21IFocus &Oslash;yeklinikk AS, Haugesund, Norway; 2Science in Vision, Akron, NY, USAPurpose: To compare the visual acuity (VA) and quality of vision between bilateral implantation of a trifocal intraocular lens (IOL) and blended bifocal IOLs with an intermediate add in the dominant eye and a near add in the nondominant eye.Patients and methods: Patients with either trifocal or blended bifocal IOLs implanted were recruited after surgery. Subjects returned for a single diagnostic visit between 3 and 24 months after surgery. VA was tested at various distances, including low-contrast acuity and acuity at their preferred reading distance. A binocular defocus curve was obtained, and subjective visual function and quality of vision were evaluated.Results: Twenty-five trifocal subjects and 30 blended bifocal subjects were enrolled. There were no significant differences in low-contrast acuity, preferred reading distance, or acuity at that reading distance. Binocular vision at 4 m, 60 cm, and 40 cm was not statistically significantly different. The trifocal provided statistically significantly better visual acuity (P&lt;0.05) at vergences from -0.5 to -1.5 D (from 2 m to 67 cm viewing distance, P&lt;0.05). There was no statistically significant difference in the near vision subscale scores of the 39-question National Eye Institute Visual Function Questionnaire or the overall scores of the Quality of Vision questionnaire, though significantly more trifocal subjects reported that the observed visual disturbances were &ldquo;bothersome&rdquo; (P&lt;0.05).Conclusion: Both lens modalities provided subjects with excellent binocular near and distance vision, with similar low rates of visual disturbances and good reported functional vision. The trifocal IOL provided significantly better intermediate VA in the viewing distance range of 2 m to 67 cm, corresponding to viewing things such as a car dashboard or grocery shelf. VA was similar between groups at viewing distances from 60 to 40 cm, corresponding to computer or reading distance.Keywords: ReSTOR, At LISA tri, multifocal IOL, cataract, presbyopi

A review of results after implantation of a secondary intraocular lens to correct residual refractive error after cataract surgery

Kjell Gunnar Gundersen,1 Rick Potvin2 1Ifocus &Oslash;yeklinikk AS, Haugesund, Norway; 2Science in Vision, Akron, NY, USA Purpose: The purpose of this study was to provide clinical outcomes data related to secondary intraocular lens (IOL) implantation for the correction of residual refractive error after cataract surgery.Patients and methods: A chart review was conducted to identify all eyes implanted with the monofocal spherical or toric AddOn&reg; secondary IOL. Data were collated from charts where uncomplicated initial cataract surgery was completed. Measures of interest included the original IOL implanted, the postoperative refractive error (before secondary IOL implantation) and the associated corrected and uncorrected visual acuities (VAs). Postoperative data of interest included the residual refractive error, the best-corrected visual acuity (BCVA) and uncorrected visual acuity (UCVA).Results: Refractive and VA data from 1 week to 3 months post-surgery were available for 46 of 70 eyes implanted with a secondary IOL by one surgeon at one practice between 4/15 and 3/17. There was a statistically significant improvement in UCVA of about 2 lines after surgery (p&lt;0.01), with no change in BCVA (p=0.94). No eyes lost a line of BCVA. There was a statistically significant reduction in the absolute magnitude of the residual spherical equivalent refractive error (p&lt;0.01). In the 10 cases with a toric secondary IOL, there was a statistically significant reduction in refractive cylinder (p&lt;0.01).Conclusion: The secondary IOL studied here appears to be a viable surgical option to correct residual refractive error after primary IOL implantation. Keywords: AddOn, piggyback, toric, astigmatism, multifocal, secondary IO

Trifocal intraocular lenses: a comparison of the visual performance and quality of vision provided by two different lens designs

Kjell G Gundersen,1 Rick Potvin2 1IFocus &Oslash;yeklinikk AS, Haugesund, Norway; 2Science in Vision, Akron, NY, USA Purpose: To compare two different diffractive trifocal intraocular lens (IOL) designs, evaluating longer-term refractive outcomes, visual acuity (VA) at various distances, low contrast VA and quality of vision.Patients and methods: Patients with binocularly implanted trifocal IOLs of two different designs (FineVision [FV] and Panoptix [PX]) were evaluated 6 months to 2 years after surgery. Best distance-corrected and uncorrected VA were tested at distance (4 m), intermediate (80 and 60 cm) and near (40 cm). A binocular defocus curve was collected with the subject&rsquo;s best distance correction in place. The preferred reading distance was determined along with the VA at that distance. Low contrast VA at distance was also measured. Quality of vision was measured with the National Eye Institute Visual Function Questionnaire near subset and the Quality of Vision questionnaire.Results: Thirty subjects in each group were successfully recruited. The binocular defocus curves differed only at vergences of &minus;1.0 D (FV better, P=0.02), &minus;1.5 and &minus;2.00 D (PX better, P&lt;0.01 for both). Best distance-corrected and uncorrected binocular vision were significantly better for the PX lens at 60 cm (P&lt;0.01) with no significant differences at other distances. The preferred reading distance was between 42 and 43 cm for both lenses, with the VA at the preferred reading distance slightly better with the PX lens (P=0.04). There were no statistically significant differences by lens for low contrast VA (P=0.1) or for quality of vision measures (P&gt;0.3).Conclusion: Both trifocal lenses provided excellent distance, intermediate and near vision, but several measures indicated that the PX lens provided better intermediate vision at 60 cm. This may be important to users of tablets and other handheld devices. Quality of vision appeared similar between the two lens designs. Keywords: FineVision, Panoptix, multifocal, defocus curve, contrast sensitivit