Published papers

Purpose: To evaluate the postoperative outcome of toric intraocular lens (TIOL) implantation for cataract patients with high corneal astigmatism. Methods: This retrospective study included 24 eyes of 22 patients with high corneal astigmatism exceeded-1.50 D who underwent cataract surgery and implantation of TIOL (SN6AT6:12 eyes, SN6AT7:8 eyes, SN6AT8:3 eyes, SN6AT9:1 eye). The mean age of all cases was 68.1 years. Visual acuity, corneal astigmatism, subjective refraction, and rotation error were recorded preoperatively and 1 month postoperatively. Results: The uncorrected and correted distance visual acuities and subjective refraction were significantly (p<0.001) improved after TIOL implantation. There was no significant difference in corneal astigmatism between preoperatively and postoperatively. The mean rotation error was 2.8°. Conclusion: TIOL was effective for cataract patients with high corneal astigmatism.

Purpose: To study the changes in corneal aberrations after cataract surgery. Methods: This study comprised 36 eyes of 36 patients (mean age, 67.3 years) who underwent cataract surgery through a 2.2-mm superior sclerocorneal incision. The anterior, posterior, and total corneal wavefront aberrations for the 6.0-mm pupillary diameter were measured preoperatively and 1 month postoperatively. The postoperative changes in corneal aberrations were evaluated for individual Zernike terms (Z2 −2, Z2 0, Z2 2, Z3 −1, Z3 1, and Z4 0) and the root mean squares of the third, fourth, and total higher-order aberrations (S3, S4, and THOA). Results: No significant postoperative changes were observed in S3 and S4 of the total and anterior cornea, although significant changes were observed in S4 and THOA of the posterior cornea. Regarding the preoperative and postoperative Zernike terms of the total cornea, the oblique astigmatism (Z2 −2) changed significantly (P = 0.02). Significant positive correlations were observed in the Z2 −2, Z2 0, Z2 2Z3 −1, Z3 1and Z4 0between the changes in the total and the anterior cornea (P <0.001 for all comparisons). However, no correlations were observed in the changes in the Zernike terms between the total and the posterior cornea, except for the Z2 0. Conclusions: The oblique astigmatism (Z2 −2) of the total cornea significantly changed after 2.2-mm-incision cataract surgery. The changes in the lower- and higher-order aberrations of the anterior cornea mainly contributed to the changes in the total cornea.

Purpose: To compare the clinical outcomes of 3 marking methods for toric intraocular lens (IOL) implantation in cataract patients. Methods: This study included 48 eyes of 48 cataract patients who underwent cataract surgery with toric IOL implantation. The rotational errors of 3 marking methods—the iris pattern marking method (iris pattern group), the pendulum marking method (pendulum group), and the 3-point marking method (3-point group)—were assessed. Results: The respective rotational errors were 4.0° ± 3.1° (mean ± SD), 5.3° ± 4.1°, and 7.3° ± 6.0°. The iris pattern group had significantly (P = 0.048) smaller rotational errors than did the 3-point group; no significant difference was found between the iris pattern and pendulum groups. However, the differences in postoperative uncorrected distance visual acuity and astigmatism did not reach significance among the 3 groups. Conclusion: The refractive and visual results of toric IOL implantation using the 3-point marking method were comparable to the other methods evaluated in this study, although the accuracy of the axis alignment of the toric IOLs was significantly lower than that obtained with the iris pattern method.

Purpose: To compare the accuracy of several methods of intraocular lens (IOL) power calculations used for cataract surgery in eyes treated with phototherapeutic keratectomy (PTK) that results in changes in the anterior corneal surface and axial length; these results make power calculations less predictable. Methods: We evaluated the medical records of 23 eyes of 13 patients (mean age, 68.8 years; range 62–80 years) who underwent cataract surgery after PTK at Keio University Hospital, Tokyo, Japan. The prediction error, defined as the difference between the estimated postoperative spherical equivalent and the postoperative manifest refraction at the spectacle plane, was calculated using five formulas: SRK/T, Haigis-L, Shammas-PL, Camellin–Calossi, and OKULIX ray tracing software. We compared the median values of the arithmetic and absolute prediction errors among the five formulas. Results: The median arithmetic errors after cataract surgery for the five formulas were 0.70 D (diopter) (range −0.41 to 2.78), −0.96 D (range −2.14 to 0.81), −0.81 D (range −1.89 to 1.15), −0.04 D (range −1.35 to 1.47), and 0.68 D (range −0.61 to 2.50), respectively. Conclusion: The Camellin–Calossi formula is a good option for calculating IOL powers in eyes that underwent PTK.

© 2019, The Author(s). This study compared the axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), mean anterior corneal radius of curvature (Rm), and postoperative refractive outcomes obtained from two different swept-source optical coherence biometers, the ARGOS (Movu, Nagoya, Japan), which uses the segmental refractive index for each segment, and the IOLMaster 700 (Carl Zeiss Meditec, Jena, Germany), which uses an equivalent refractive index for the entire eye. One hundred and six eyes of 106 patients with cataracts were included. The refractive outcomes using the Barrett Universal II, Haigis, Hoffer Q, and SRK/T formulas were evaluated. The mean AL, CCT, ACD, and Rm differed significantly (P < 0.001) with the IOLMaster 700 (25.22 mm, 559 µm, 3.23 mm, and 7.69 mm) compared with the ARGOS (25.14 mm, 533 µm, 3.33 mm, and 7.66 mm). The mean LTs did not differ significantly. The percentages of eyes within ±0.50 and ±1.00 diopter of the predicted refraction did not differ significantly (P > 0.05). The accuracy of the intraocular lens power calculations was clinically acceptable with both biometers, although the ocular biometry using these two biometers exhibited certain differences.