Futoshi Taketani

Influence of intraocular lens tilt and decentration on wavefront aberrations

Purpose: To investigate the influence of intraocular lens (IOL) tilt and decentration on higher‐order aberrations (HOAs) using wavefront analysis. Setting: Department of Ophthalmology, Nara Medical University, Nara, Japan. Methods: Forty eyes of 40 patients with a 5.5 mm optic, foldable acrylic IOL were examined 4 to 48 months postoperatively. Ocular wavefront aberrations of the central 4.0 mm aperture diameter were measured using a Hartmann‐Shack aberrometer. Higher‐order aberrations from the 3rd to 4th order were calculated using Zernike polynomials. The relationship between IOL tilt and decentration, measured with a Scheimpflug camera, and ocular HOAs were investigated. Results: The correlation between IOL tilt and coma‐like aberrations was significant (r = 0.431, Spearman rank correlation coefficient; P = .007). However, the correlation between IOL tilt and the spherical‐like and total aberrations was not significant (P>.05), nor was the correlation between IOL decentration and coma‐like, spherical‐like, and total aberrations (P>.05). Conclusions: Intraocular lens tilt influenced ocular coma‐like aberrations. The quality of the retinal image may improve by reducing IOL tilt.

Effect of total higher-order aberrations on accommodation in pseudophakic eyes.

PURPOSE: To analyze the effect of total higher‐order aberrations (HOAs) on the range of accommodation in pseudophakic eyes and the size of near‐vision optotypes. SETTING: Department of Ophthalmology, Nara Medical University, Nara, Japan. METHODS: The study comprised 30 patients (44 eyes) who were diagnosed with cataract at Nara University of Medical Science Hospital and Municipal Oyodo Hospital. Inclusion criteria included no other eye disorder and a best corrected distance acuity of 20/20 or better 1 month after cataract surgery. All patients had small‐incision phacoemulsification followed by in‐the‐bag implantation of a monofocal intraocular lens (SA60AT, Alcon). All incisions were self‐sealing. Accommodation in pseudophakic eyes was measured by the lens‐loading method in an examination room under constant illumination. Ocular HOAs were measured using the KR‐9000PW Hartmann‐Shack wavefront analyzer (Topcon). RESULTS: The mean patient age was 75.8 years ± 5.4 (SD) (range 64 to 83 years). The Pearson correlation coefficient (r) showed a significant positive correlation between the range of accommodation and Z7 (vertical coma) for a 4.0 mm pupil using the 1.0 near‐vision optotype. There was a significant negative correlation between the range of accommodation and Z12 (spherical aberration) for a 4.0 mm pupil using the 1.0 near‐vision optotype (r = .311, P = .040 for Z7; r = −.365, P = .015 for Z12). No other parameter was significantly correlated with the range of accommodation. CONCLUSIONS: Measurement of accommodation in pseudophakic eyes by the lens‐loading method using the 1.0 near‐vision optotype showed that eyes with larger vertical coma aberrations achieved a larger range of accommodation. In contrast, eyes with larger spherical aberrations had smaller amounts of accommodation. The size of the near‐vision optotype may affect accommodation analysis in pseudophakic eyes.

High-order aberrations with Hydroview H60M and AcrySof MA30BA intraocular lenses: Comparative study

Purpose: To compare differences in high‐order aberrations between 2 intraocular lenses (IOLs), the Hydroview® H60M (Bausch & Lomb) and AcrySof® MA30BA (Alcon). Setting: Department of Ophthalmology, Nara Medical University, Nara, Japan. Method: Twenty‐four eyes of 14 patients with a Hydroview IOL and 25 eyes of 20 patients with an AcrySof IOL who had uneventful phacoemulsification and a best corrected visual acuity better than 20/16 from 6 to 12 months after surgery were evaluated. High‐order aberrations were measured using a Hartmann‐Shack aberrometer at 4.0 mm and 6.0 mm wavefront aperture diameters, and IOL tilt and decentration were assessed by Scheimpflug videophotography. Results: There were no differences between the 2 groups in IOL tilt and decentration (P>.05, Mann‐Whitney U test). In the cornea, there were no differences between the 2 groups in high‐order aberrations at 4.0 mm and 6.0 mm aperture diameters (P>.05, Mann‐Whitney U test). In the whole eye, there was a significant difference between Hydroview (mean 0.441 &mgr;m ± 0.147 [SD]) and AcrySof (0.696 ± 0.287 &mgr;m) IOLs in spherical‐like aberrations at the 6.0 mm aperture diameter (P = .00008, Mann‐Whitney U test); there were no differences between the 2 groups in other aberrations. Conclusions: The type of IOLs influenced spherical‐like aberrations. The IOLs shape was a particularly important factor in spherical‐like aberrations. The aberrations may affect night driving in certain individuals.

Influence of intraocular lens optical design on high-order aberrations.

Purpose: To compare differences in high‐order aberrations (HOAs) between 2 intraocular lens (IOL) optical designs. Setting: Department of Ophthalmology, Nara Medical University, Nara, Japan. Method: Sixty eyes that had uncomplicated phacoemulsification and IOL implantation were assigned to 1 of 2 groups based on the type of IOL optical design: more posteriorly curved biconvex shape (AcrySof MA30BA, Alcon) (n = 30 eyes) or more anteriorly curved biconvex shape (AcrySof MA30AC) (n = 30 eyes). All patients had best corrected visual acuity better than 20/25. High‐order aberrations were measured using a Hartmann‐Shack aberrometer at 4.0 mm and 6.0 mm wavefront aperture diameters. Results: At 4.0 mm aperture diameters, there were no differences between the 2 groups in HOAs (P>.05, Mann‐Whitney U test) in the cornea and the whole eye. At 6.0 mm aperture diameters, MA30AC eyes had a smaller amount of spherical‐like aberrations (P = .043) than MA30BA eyes; however, there were no significant differences between the 2 groups in coma‐like aberrations and total aberrations in the whole eye (P>.05). At 6.0 mm aperture diameters, there were no differences between the 2 groups HOAs in the cornea. (P>.05). Conclusion: The optical design of the spherical IOL influenced the spherical‐like aberrations in the whole eye. This may reduce retinal image quality.

Effect of tilt of 2 acrylic intraocular lenses on high-order aberrations

Purpose: To investigate the high‐order aberrations (HoAs) in pseudophakia between 2 foldable acrylic intraocular lenses (IOL) with differences in the tilt of IOL. Setting: Department of Ophthalmology, Nara Medical University, Nara, Japan. Method: Sixty‐four eyes that had uncomplicated phacoemulsification and IOL implantation were assigned to 1 of 2 groups: Acryfold 60BB (HOYA [n = 30 eyes]) and AcrySof MA60AC (Alcon [n = 34 eyes]). All patients had best corrected visual acuity better than 20/25. High‐order aberrations were measured using the Hartmann‐Shack aberrometer at 4.0 mm and 6.0 mm wavefront aperture diameters, and the IOL tilt and decentration were measured using Scheimpflug videophotography. Results: There was a significant difference in the IOL tilt (60BB = 2.22 degrees ± 1.44 (SD), 60AC = 3.18 ± 1.84 degrees; P = .041, Mann‐Whitney U test), but no difference in IOL decentration (P>.05). In the cornea, there were no differences between the 2 groups in HoAs at 4.0 mm and 6.0 mm aperture diameters (P>.05, Mann‐Whitney U test). In the whole eye, there was no difference between the 2 groups in spherical‐like aberrations, coma‐like aberrations, and total aberrations at the 4.0 mm and 6.0 mm aperture diameters (P>.05). The compensation of the internal optics with the 60BB group was better than with the 60AC group for coma‐like (P = .037) and total aberrations (P = .010) at 6.0 mm aperture diameter. Conclusion: The smaller tilt of the IOL induced more compensation for the coma‐like and total aberrations at the 6.0 mm aperture diameter. The IOL tilt should be small, especially in a large pupil, with regard to HoAs.

Impact of Nuclear Cataract Density on Postoperative Refractive Outcome: IOL Master versus Ultrasound

Purpose: To evaluate the effect of cataract density on the postoperative refractive outcome. Methods: For 59 nuclear cataract eyes, the axial length was preoperatively measured by the IOL Master (Zeiss, Germany) and ultrasound (US; UD-6000, Tomey, Japan) and the cataract density by EAS-1000 (Nidek, Japan). The prediction error was used as evaluation of the accuracy of ocular biometry. Results: There were significant differences between IOL Master and US in the mean error (0.24 ± 0.63 vs. 0.69 ± 0.64 dpt, p < 0.001) and the mean absolute error (0.57 ± 0.36 vs. 0.79 ± 0.53 dpt, p < 0.001). The cataract density was significantly correlated with the prediction error with IOL Master (r = 0.24, p = 0.03) and US (r = 0.29, p = 0.01). Conclusions: Measurements with the IOL Master are slightly affected by the cataract density due to the refractive index change, but its accuracy is less affected than US.

Change in Dynamic Visual Acuity (DVA) by Pupil Dilation

Objective: This study was conducted to assess dynamic visual acuity (DVA) under pupil dilation. Background: Pupil dilation may negatively affect driving performance. Methods: Thirty healthy young adults (mean age 29.4 years) with pupil dilation participated in this study as the Mydrin P group. In addition to them, 15 healthy young adults (mean age 28.5 years) without pupil dilation were enrolled as the control group. DVA was measured binocularly with free-head viewing at 0, 30, 60, 120, and 360 min after mydriatic drop instillation in both eyes. Pupil size was measured at each time. Results: In the Mydrin P group, DVA significantly improved at 30, 60, and 120 min (ANOVA; p < .01) but returned to the predilation level at 360 min (ANOVA; p = .61). Pupil size changed from 4.1 to 7.8 mm (ANOVA; p < .01) at 30 min after the instillation, and this level was maintained up to 120 min but returned to normal within 360 min. In the control group, DVA did not significantly change at all measured times (ANOVA; p > .9). DVA was significantly (p < .05) correlated with the pupil size at all measured times. Conclusion: The improvement in DVA was related to the enlargement of the pupil. This study suggests that the pupil size is one factor that may affect DVA. Application: Potential applications of this study include useful information to assess the effect of pupil dilation on driving performance.

Pattern-Reversal Visual Evoked Potentials in Patients with Human T-lymphotropic Virus Type 1 Uveitis

Purpose: The purpose of this study was to evaluate the possible injury in the optic pathway by measuring P100 peak latency of pattern-reversal visual evoked potentials (PVEPs) in patients with human T-lymphotropic virus type 1 uveitis (HU). Methods: The P100 peak latency of PVEP was measured during the period without macular abnormalities observed by fluorescein angiography in 23 patients (46 eyes) with HU and 24 patients (48 eyes) with Vogt-Koyanagi-Harada disease (VKH) with a corrected visual acuity of 20/25 or more. To determine the normal upper limit of P100 peak latency, PVEPs were measured in 31 normal subjects (31 eyes). In addition, in the HU patients, the serum anti-HTLV-1 antibody titer was measured by particle agglutination assay within 3 months of PVEP recording, and the period of HU was retrospectively surveyed. Results: Delayed latency was observed in 4 (7 eyes) of the 23 patients (46 eyes) with HU but none of the 24 patients (48 eyes) with VKH. All four patients with delayed latency showed a serum anti-HTLV-1 antibody titer of more than ×4000. The HU period in the HU patients was 0.2–14.0 years, and the HU periods in the four patients with delayed latency were 0.8, 2.7, 4.2, and 14.0 years, respectively. Conclusions: We measured pattern-reversal visual evoked potentials and observed delayed P100 peak latency in 7 of the 46 eyes in 4 (17.4%) of the 23 HU patients. This suggests injury in the optic pathway including the optic nerve by HTLV-1 in some patients with HU. In the future, consideration should also be given to the possible development of optic neuropathy due to HTLV-1.

A child with epilepsy in whom multifocal VEPs facilitated the objective measurement of the visual field

Summary:  Purpose: We investigated whether visual field defects can be objectively evaluated by using multifocal visual evoked potential (multifocal VEP) in children with epilepsy in whom it is difficult to measure the visual field.

Multifocal visual-evoked potentials in patients with schizophrenia during treatment.

Aim: Investigation of responses of multifocal visual-evoked potentials (mfVEPs) in schizophrenic patients under treatment in whom no abnormality was detected on the conventional perimetry. Methods: Recordings of mfVEPs were performed in 31 schizophrenic patients and 30 normal subjects using a VERIS Junior Science recording apparatus (Mayo, Aichi, Japan). Responses from eight sites in each subject were divided into four quadrants (superior and inferior temporal quadrants, and superior and inferior nasal quadrants). In each quadrant, two response waves were grouped and averaged, and the latency and amplitude of main waveforms that appeared near 100 ms were evaluated. Results: The peak latency was about 7–9 ms prolonged and the amplitude was reduced by about 2–5 nV/deg2 in the schizophrenic patient group compared to those in the normal subject group, and significant differences were noted in both parameters in all quadrants. Conclusion: In schizophrenic patients under treatment with psychotropic agents, prolongation of the latency and amplitude reduction were noted in mfVEPs even though no abnormality was detected on the conventional perimetry.