Misae Ito

Clinical outcomes of wavefront-guided laser in situ keratomileusis: 6-month follow-up

Purpose: To evaluate the clinical outcomes 6 months after wavefront‐guided laser in situ keratomileusis (LASIK) for myopia in Japan. Setting: Department of Ophthalmology, Sanno Hospital, Tokyo, Japan. Methods: This prospective study comprised 22 eyes of 12 patients treated with wavefront‐guided LASIK who were available for evaluation at 6 months. The mean patient age was 31.2 years ± 8.4 (SD) (range 23 to 50 years), and the mean preoperative spherical equivalent refraction was −7.30 ± 2.72 diopters (D) (range −2.75 to −11.88 D). In all cases, preoperative wavefront analysis was performed with a Hartmann‐Shack aberrometer and the Technolas® 217z flying‐spot excimer laser system (Bausch & Lomb) was used with 1.0 mm and 2.0 mm spot sizes and an active eye tracker with a 120 Hz tracking rate. The clinical outcomes of wavefront‐guided LASIK were evaluated in terms of safety, efficacy, predictability, stability, complications, and preoperative and postoperative aberrations. Results: At 6 months, 10 eyes had no change in best spectacle‐correct visual acuity and 10 gained 1 or more lines. The safety index was 1.11 and the efficacy index, 0.82. Slight undercorrections were observed in highly myopic eyes. In all eyes, the postoperative refraction tended slightly toward myopia for 3 months and stabilized after that. No complication such as epithelial ingrowth, diffuse lamellar keratitis, or infection was observed. Comparison of the preoperative and postoperative aberrations showed that 2nd‐order aberrations decreased and higher‐order aberrations increased. In the 3rd order, aberrations increased in the high‐myopia group (−6.0 D or worse) and decreased in the low to moderate‐myopia group (better than −6.0 D). Conclusion: Wavefront‐guided LASIK was a good option for refractive surgery, although a longer follow‐up in a larger study is required.

Assessment of visual performance in pseudophakic monovision

PURPOSE: To assess the visual performance and acceptability of pseudophakic monovision and examine its relationship to age. SETTING: Department of Ophthalmology, Kitasato University Hospital, Kanagawa, Japan. METHODS: This retrospective study examined patients with pseudophakic monovision using monofocal intraocular lenses. Refractive errors, visual acuity at various distances, contrast sensitivity, and near stereopsis were measured. Patient satisfaction with monovision was evaluated using a questionnaire. RESULTS: Eighty‐two patients (age 49 to 87 years) were evaluated. The mean difference in spherical equivalent refractive error between each patients eyes was 2.27 diopters. Most patients had a binocular uncorrected visual acuity of 0.10 logMAR or better at all distances. For contrast sensitivity, binocular summation was observed at 1.5 to 6.0 cycles per degree. Near stereopsis was in the normal range, which was up to 100 seconds of arc. Questionnaire responses showed that 81% of patients (64% <60 years; 87% between 60 years and 70 years; 94% older than 70 years) were satisfied with the results. CONCLUSION: Pseudophakic monovision was an effective approach for managing loss of accommodation after cataract surgery in patients older than 60 years; however, a careful selection process is required.

Reading ability with pseudophakic monovision and with refractive multifocal intraocular lenses: Comparative study

PURPOSE: To the compare the reading ability after bilateral cataract surgery in patients who had pseudophakic monovision achieved by monofocal intraocular lens (IOL) implantation and patients who had refractive multifocal IOL implantation. SETTING: Department of Ophthalmology, Kitasato University Hospital, Kanagawa, Japan. METHODS: This study evaluated patients who had bilateral cataract surgery using the monovision method with monofocal IOL implantation to correct presbyopia (monovision group) or who had bilateral cataract surgery with refractive multifocal IOL implantation (multifocal group). In the monovision group, the dominant eye was corrected for distance vision and the nondominant eye for near vision. The maximum reading speed, critical character size, and reading acuity were measured binocularly without refractive correction using MNREAD‐J acuity charts. RESULTS: The monovision group comprised 38 patients and the multifocal group, 22 patients. The mean maximum reading speed was 350.5 characters per minute (cpm) ± 62.3 (SD) in the monovision group and 355.0 ± 53.3 cpm in the multifocal group; the difference was not statistically significant. The mean critical character size was 0.24 ± 0.12 logMAR and 0.40 ± 0.16 logMAR, respectively (P<.05). The mean reading acuity was 0.05 ± 0.12 logMAR and 0.19 ± 0.11 logMAR, respectively (P<.01). The monovision group had better critical character size and reading acuity results. CONCLUSION: The monovision method group had better reading ability; however, careful patient selection is essential.

Five-year clinical study of patients with pseudophakic monovision

PURPOSE: To assess the long‐term clinical outcomes and acceptability of pseudophakic monovision. SETTING: Department of Ophthalmology, Kitasato University Hospital, Kanagawa, Japan. DESIGN: Case series. METHODS: Patients who had surgery using the monovision method with monofocal intraocular lenses had routine postoperative examinations. Assessed were visual acuity, near stereopsis, ocular deviation, patient satisfaction, and the rate of spectacle dependence preoperatively and 1, 3, and 6 months and 1, 2, 3, 4, and 5 years postoperatively. RESULTS: The study enrolled 54 patients with a mean age of 74.7 years ± 7.9 (SD). The mean difference in the spherical equivalent refractive error between eyes of each patient was 2.13 diopters. The binocular uncorrected distance visual acuity was at least 0.10 logMAR in 98% of patients, with 76% achieving Jaeger 2 or better binocular uncorrected near visual acuity. Near stereopsis in patients who shifted from exophoria to intermittent exotropia decreased, although no serious problems were observed. The rate of spectacle dependence was 88% preoperatively, 41% at 1 year, and 22% at 5 years. Patient satisfaction improved gradually during the follow‐up. CONCLUSION: Pseudophakic monovision was an effective approach for correcting presbyopia throughout the 5‐year observation period; however, a longer follow‐up, including further studies is necessary to allow selection of appropriate patients. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Association between ocular dominance and refractive asymmetry.

PURPOSE To investigate the association between ocular dominance (sighting dominance) and refractive asymmetry in phakic patients. METHODS This retrospective study included 3,012 patients with a mean age of 29.0 ± 5.3 years (range: 20 to 39 years). Refractive error was determined with cycloplegic refraction and axial length was determined with IOLMaster (Carl Zeiss Meditec, Dublin, CA). Ocular dominance was assessed using the hole-in-the-card test. RESULTS The right and left eyes were dominant in 77.7% and 22.3% of the patients, respectively. In the high anisometropia group (⩾ 2.0 diopters), the non-dominant eyes had significantly higher myopic spherical equivalents and longer axial lengths than the dominant eyes (P < .05). However, there were no significant differences in these parameters in the low anisometropia group. CONCLUSION The current study revealed that non-dominant eyes had a greater myopic refractive error and longer axial length than the dominant eyes, especially in the patients who had high amounts of anisometropia.

Pseudophakic monovision using monofocal and multifocal intraocular lenses: Hybrid monovision

PURPOSE: To evaluate the visual function after bilateral cataract surgery performed with a new technique (hybrid monovision) that uses a monofocal intraocular lens (IOL) and a diffractive multifocal IOL. SETTING: Department of Ophthalmology, Kitasato University Hospital, Kanagawa, Japan. DESIGN: Case series. METHODS: Hybrid monovision was achieved by implanting a monofocal IOL (AQ310Ai) in the dominant eye and a diffractive multifocal IOL (Tecnis ZM900) in the nondominant contralateral eye. The target refraction was emmetropia in both eyes. Visual acuity at various distances, contrast sensitivity, near stereopsis, reading ability, and the degree of patient satisfaction were measured. RESULTS: The study enrolled 32 patients with a mean age of 61.2 years ± 14.7 (SD). At all distances, the mean binocular visual acuity was better than 0.1 logMAR. Binocular contrast sensitivity was better than monocular vision in the eye with the diffractive multifocal IOL. Near stereopsis within normal range was maintained in 62.5% of patients. Of the patients, 18.8% reported spectacle dependence. With binocular vision, no patients reported waxy vision (ie, as though they were looking through water). CONCLUSION: Hybrid monovision may be an effective approach for managing loss of accommodation after cataract surgery and may be the method of choice in cases of waxy vision caused by bilateral multifocal IOL implantation. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Effect of pupil size on visual acuity in a laboratory model of pseudophakic monovision.

PURPOSE To investigate the effect of pupil size on visual acuity in pseudophakic monovision. METHODS For the simulation, a modified Liou-Brennan model eye was used. The model eye was designed to include a centered optical system, corneal asphericity, an iris pupil, a Stiles-Crawford effect, an intraocular lens, and chromatic aberration. Calculation of the modulation transfer function (MTF) was performed with ZEMAX software. Visual acuity was estimated from the MTF and the retinal threshold curve. The sizes of the entrance pupil were 2.0, 2.5, 3.0, and 4.0 mm. RESULTS Decreasing pupil diameter and increasing myopia progressively improved near visual acuity. For an entrance pupil size of 2.5 mm and a refractive error of -1.50 diopters, the logMAR value (Snellen; metric) in the non-dominant eye at 40 cm was 0.06 (20/23; 6/6.9). CONCLUSIONS Knowledge of the patients pupil diameter at near fixation can assist surgeons in determining the optimum degree of myopia for successful monovision.

Five-year follow-up of ocular deviation in bilaterally pseudophakic patients.

ABSTRACT Purpose: To investigate long-term ocular deviation in patients who had undergone implantation of a monofocal intraocular lens (IOL) in both eyes. Methods: Eighty-eight patients with exophoria (average age, 68 ± 8 years; average axial length, 23.9 ± 0.9 mm) scheduled for bilateral phacoemulsification and monofocal IOL implantation were recruited. Before surgery and at 1, 3, and 6 months and 1, 2, 3, 4, and 5 years after surgery, we assessed ocular deviation near stereopsis in patients wearing their normal spectacles. Results: At 5 years after surgery, near stereopsis had a median value of 50 arcsec and the mean stereopsis was 85.8 ± 101.8 arcsec; 85 patients (85%) had good stereopsis (ie, ≥100 arcsec). Of the total patients, 12.5% shifted from exophoria to intermittent strabismus or exotropia at near vision, and near stereopsis decreased. Most of them had a preoperative near exophoria angle of more than 12 prism diopters. Conclusion: In bilaterally pseudophakic patients with a near exophoria angle of more than 12 prism diopters, we should be concerned about the possibility of variations in ocular deviation and stereopsis after cataract surgery.

Evaluation of visual function in preschool-age children using a vision screening protocol

Purpose To evaluate the relationship between uncorrected visual acuity and refraction and binocular function using a vision screening protocol. Methods In total, 760 children (3–6 years old) who were enrolled in 4 nursery schools in Otawara, Japan, were recruited; a total of 1,520 eyes were examined. We assessed uncorrected near visual acuity, manifest refraction, stereopsis, and eye position. Subjects were divided into 4 subgroups according to the lowest uncorrected near visual acuity value compared between the 2 eyes: group 1 (visual acuity [VA] ≤0.00 [logarithm of the minimum angle of resolution]), group 2 (VA 0.15–0.05), group 3 (VA 0.52–0.22), and group 4 (VA >0.52). These parameters were compared among the groups. Results The sample number of each of the 4 sub-groups was as follows: group 1, 608; group 2, 114; group 3, 27; and group 4, 11. The median spherical equivalent values were −1.13 diopter (D) in group 1 and −1.00 in group 2, which were more myopic than group 4. Median cylindrical power in group 1 was 0.25 D, and was the lowest among all groups. In group 1, median anisometropia was 0.38 D and median corneal astigmatism value was 1.13 D; both values were lowest in group 1. With regard to binocular function, 89.6% of the subjects in group 1 had 60 arcseconds or better in near stereopsis and 98.8% had no detectable strabismus, which were significantly different from the findings in the other groups. The percentage of subjects in group 1 who had 80 arcseconds or worse in near stereopsis was 10.4%. In contrast, 90.9% of the subjects in group 4 had 80 arcseconds or worse in near stereopsis, and 18.2% had intermittent or manifest strabismus. Conclusion We suggest that examination of refraction and stereopsis in preschool-age children undergoing vision screening is an important supplement to visual acuity testing.

Association Between Ocular Dominance and Anisometropic Hyperopia

Introduction and Purpose Anisometropia, a relative difference in the refractive state of the two eyes, is common in hyperopic patients. We investigated the association between ocular dominance (sighting dominance) and refractive asymmetry in patients with hyperopia. Methods This retrospective study included 223 hyperopic patients with a mean age of 10.1 ± 3.6 years (range 3 to 21 years). Refractive error was measured with cycloplegic refraction, and axial length was measured with IOLMaster® (Carl Zeiss Meditec, Dublin, CA). Ocular dominance was assessed with the hole-in-the-card test. The amount of hyperopic anisometropia was subdivided into four groups: less than 0.50 D, 0.50–0.99 D, 1.00–1.99 D, and 2.00 D or greater. Results Ocular dominance of the right and left eye was seen in 66% and 34% of the patients, respectively. The nondominant eye had higher hyperopia, astigmatism, and shorter axial length than the dominant eye (P < 0.001). In the group with spherical equivalent anisometropia of ≥0.50 D in particular, the nondominant eye was significantly more hyperopic and had shorter axial length than the dominant eye (both P < 0.001). Conclusions The current study revealed that the nondominant eye had a greater hyperopic refractive error and shorter axial length than the dominant eye, in patients who had a high degree of anisometropia in particular.