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(Investigative Ophthalmology and Visual Science. 2006;47:1334-1338.)
© 2006 by The Association for Research in Vision and Ophthalmology, Inc.
DOI:  10.1167/iovs.05-1154
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Influence of Pupil Diameter on the Relation between Ocular Higher-Order Aberration and Contrast Sensitivity after Laser In Situ Keratomileusis

Tetsuro Oshika,1 Tadatoshi Tokunaga,2 Tomokazu Samejima,2 Kazunori Miyata,2 Keisuke Kawana,1 and Yuichi Kaji1

1From the Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan; and 2Miyata Eye Hospital, Miyakonojo, Miyazaki, Japan.


   Abstract
Top
 Abstract
Methods
 Results
 Discussion
 References
 
PURPOSE. To investigate the influence of pupil diameter on the relation between induced changes in ocular higher-order wavefront aberrations and changes in contrast sensitivity by conventional laser in situ keratomileusis (LASIK) for myopia.

METHODS. In 215 eyes of 117 patients (age, 33.2 ± 8.3 years) undergoing LASIK for myopia of –1.25 to –13.5 D (–5.28 ± 2.55 D), ocular wavefront aberrations and contrast sensitivity function were determined before and 1 month after surgery. Preoperative photopic pupil diameter was measured with a digital camera. Ocular higher-order aberrations were measured for a 4-mm pupil with a Hartmann-Shack wavefront analyzer. The root-mean-square (RMS) of the third- and fourth-order Zernike coefficients was used to represent coma- and spherical-like aberration, respectively. From the contrast-sensitivity data, the area under the log contrast sensitivity function (AULCSF) was calculated.

RESULTS. One hundred five eyes had a photopic pupil diameter of 4 mm or larger, and the remaining 110 had a photopic pupil diameter smaller than 4 mm. There were no statistically significant differences in the background clinical data between these two groups. In the eyes with a photopic pupil diameter of 4 mm or larger, the changes in third-order comalike aberrations did not correlate with the changes in AULCSF (Pearson correlation coefficient, r = –0.037, P = 0.723) and 10% low-contrast visual acuity (r = 0.125, P = 0.224), but fourth-order spherical-like aberrations correlated significantly with the changes in AULCSF (r = –0.229, P = 0.024) and 10% low-contrast visual acuity (r = 0.221, P = 0.038). In the eyes with photopic pupil size smaller than 4 mm, there were significant correlations between the changes in comalike aberrations and the changes in AULCSF (r = –0.487, P < 0.001) and 10% low-contrast visual acuity (r = 0.310, P = 0.003), but spherical-like aberrations showed no correlation with the changes in AULCSF (r = –0.078, P = 0.485) and 10% low-contrast visual acuity (r = 0.208, P = 0.158).

CONCLUSIONS. In eyes with larger photopic pupil diameter, increases in spherical-like aberration dominantly affect contrast sensitivity, whereas in eyes with smaller pupil size, changes in comalike aberration exert greater influence on visual performance.

Previous studies have demonstrated that laser in situ keratomileusis (LASIK) significantly increases higher-order wavefront aberrations of the eye1 2 3 4 5 6 7 8 9 and reduces contrast sensitivity.9 10 11 12 13 14 15 16 17 18 19 There is a report that the induced increases in ocular higher-order aberration significantly correlated with the changes in contrast sensitivity function by LASIK.9 It has been known that the amount and character of higher-order aberrations of the eye is greatly affected by the diameter of the entrance pupil.1 20 21 22 23 It has been shown that contrast sensitivity function is also related to pupil diameter.24 25 There have been no reports, however, about the influence of pupil diameter on the relation between higher-order aberration and contrast sensitivity function after LASIK. The assessment of pupil size is one of the most important and essential preoperative examinations when selecting patients for refractive surgery, increasing the safety of refractive surgery procedures, planning the surgical strategy, and identifying patients at risk of development of symptoms or declines in visual performance after excimer laser keratorefractive surgery.26 27 28 29 We conducted the present study to investigate the influence of photopic pupil diameter on ocular aberration and visual performance after LASIK.


   Methods
Top
 Abstract
 Methods
Results
 Discussion
 References
 
Two hundred and fifteen eyes of 117 consecutive patients (male 73, female 44) undergoing LASIK for myopia were studied. Their ages ranged from 17 to 54 years (mean, 33.2 ± 8.3 [SD]), and preoperative refraction was –1.25 to –13.5 D (mean, –5.28 ± 2.55 D). The research protocol had institutional review board approval, and written informed consent was obtained from each patient. The study adhered to the tenets of the Declaration of Helsinki.

All surgeries were performed by one surgeon (KM; using the VISIX STAR S2 excimer laser system; VISX Inc., Santa Clara, CA). Laser parameters included the following: wavelength, 193 nm; radiant exposure (fluence), 160 mJ/cm2; pulse repetition rate, 10 Hz; average ablation depth per pulse, 0.23 µm on the cornea; ablation zone diameter, 6.0 mm; and transition zone, 0.35 mm. Aspiration air flow was used for debris removal. The automated microkeratome (MK-2000; Nidek Ltd., Gamagori, Japan) was used to create a hinged corneal flap of 160-µm thickness (nominal value).

Logarithm of minimum angle of resolution (logMAR) uncorrected visual acuity (UCVA), logMAR best spectacle-corrected visual acuity (BSCVA), ocular wavefront aberration, and contrast sensitivity function were evaluated before and 1 month after surgery. Pupil diameter in a photopic condition (270 lux) was measured before surgery by using digital camera (model E-300; Olympus, Tokyo, Japan).30 Accommodation was controlled by instructing the subjects to fixate on a 4-mm target. Photographs were transferred to a computer, and pupil diameter was measured with a specialized analysis software (not commercially available). Measurements and analyses were conducted by one experienced examiner.

Ocular higher-order aberrations for a 4-mm pupil were measured with a Hartmann-Shack wavefront aberrometer (model KR-9000PW; Topcon, Tokyo, Japan). The root-mean-square (RMS) of the third-order Zernike coefficients was used to represent comalike aberration, and the RMS of the fourth-order coefficients was used to denote spherical-like aberration.

We tested two indices of contrast sensitivity function: contrast sensitivity (with the CSV-1000E charts; Vector Vision Co., Greenville, OH) and low-contrast visual acuity (with the CSV-1000LanC10% charts; Vector Vision Co.). These tests were performed with best spectacle correction at 2.5 mm, both before and after surgery. The area under the log contrast sensitivity function (AULCSF) was calculated from the data obtained with the CSV-1000E sine wave grating chart. AULCSF was determined according to the method of Applegate et al.31 The log of contrast sensitivity was plotted as a function of log spatial frequency, and third-order polynomials were fitted to the data. The fitted function was integrated between the fixed limits of log spatial frequency of 0.48 (corresponding to 3 cyc/eg) and 1.26 (18 cyc/deg), and the resultant value was defined as the AULCSF. In CSV-1000LanC10%, one-line step represents a change of 0.1 logMAR units (logarithm of the minimum angle of resolution). Low contrast visual acuity was scored by giving a credit of 0.02 logMAR units for each letter correctly identified.


   Results
Top
 Abstract
 Methods
 Results
Discussion
 References
 
Data were analyzed according to the preoperative photopic pupil diameter. One hundred five eyes had a pupil diameter of 4 mm or larger, and the remaining 110 eyes had a pupil diameter smaller than 4 mm. Their background data are summarized in Table 1 . There were no statistically significant differences in the clinical data between these two groups.


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  		TABLE 1. Patients’ Clinical Data according to Preoperative Photopic Pupil Diameter

 
In the eyes with photopic pupil diameter of 4 mm or larger, the changes in third-order comalike aberrations did not correlate with the changes in AULCSF (Pearson correlation coefficient, r = –0.037, P = 0.723, Fig. 1 ) and 10% low-contrast visual acuity (r = 0.125, P = 0.224, Fig. 2 ), but fourth-order spherical-like aberrations correlated significantly with the changes in AULCSF (r = –0.229, P = 0.024, Fig. 3 ) and 10% low-contrast visual acuity (r = 0.221, P = 0.038, Fig. 4 ).


Figure 1
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  		FIGURE 1. Relation between changes in ocular comalike aberrations and changes in AULCSF (Pearson correlation coefficient, r = –0.037, P = 0.723) in eyes with a photopic pupil diameter of 4 mm or larger.

 

Figure 2
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  		FIGURE 2. Relation between changes in ocular comalike aberrations and changes in low-contrast visual acuity (Pearson correlation coefficient, r = 0.125, P = 0.224) in eyes with photopic pupil diameter of 4 mm or larger.

 

Figure 3
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  		FIGURE 3. Significant correlation between changes in ocular spherical-like aberrations and changes in AULCSF (Pearson correlation coefficient, r = –0.229, P = 0.024) in eyes with a photopic pupil diameter of 4 mm or larger.

 

Figure 4
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  		FIGURE 4. Significant correlation between changes in ocular comalike aberrations and changes in low-contrast visual acuity (Pearson correlation coefficient, r = 0.221, P = 0.038) in eyes with photopic pupil diameter of 4 mm or larger.

 
In the eyes with a photopic pupil size smaller than 4 mm, there were significant correlations between the changes in comalike aberrations and the changes in AULCSF (r = –0.487, P < 0.001, Fig. 5 ) and 10% low-contrast visual acuity (r = 0.310, P = 0.003, Fig. 6 ), but spherical-like aberrations showed no correlation with the changes in AULCSF (r = –0.078, P = 0.485, Fig. 7 ) and 10% low-contrast visual acuity (r = 0.208, P = 0.158, Fig. 8 ).


Figure 5
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  		FIGURE 5. Significant correlation between changes in ocular comalike aberrations and changes in AULCSF (Pearson correlation coefficient, r = –0.487, P < 0.001) in eyes with a photopic pupil diameter smaller than 4 mm.

 

Figure 6
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  		FIGURE 6. Significant correlation between changes in ocular comalike aberrations and changes in low-contrast visual acuity (Pearson correlation coefficient, r = 0.310, P = 0.003) in eyes with photopic pupil diameter smaller than 4 mm.

 

Figure 7
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  		FIGURE 7. Relation between changes in ocular spherical-like aberrations and changes in AULCSF (Pearson correlation coefficient, r = –0.078, P = 0.485) in eyes with photopic pupil diameter smaller than 4 mm.

 

Figure 8
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  		FIGURE 8. Relation between changes in ocular comalike aberrations and changes in low-contrast visual acuity (Pearson correlation coefficient, r = –0.078, P = 0.485) in eyes with photopic pupil diameter smaller than 4 mm.

 

   Discussion
Top
 Abstract
 Methods
 Results
 Discussion
References
 
We investigated the influence of ocular higher-order wavefront aberration on contrast sensitivity function in relation to photopic pupil size. The results indicated that in the eyes with large pupils, contrast sensitivity was influenced by spherical-like aberration more than by comalike aberration. In contrast, in the eyes with small pupils, comalike aberration exerted greater influence than did spherical-like aberration on contrast sensitivity. In eyes after photorefractive keratectomy (PRK), it has been reported that pupillary dilatation causes greater increases in corneal spherical-like aberration than in corneal comalike aberration.20 Another study has demonstrated that for a large pupillary aperture, comalike aberration was dominant before PRK and LASIK, but spherical-like aberration became dominant after surgery.1 In myopic eyes, Wang et al.23 reported that the change in spherical aberration was greater than that in comalike aberration when the pupil was enlarged. The results obtained herein are compatible with findings in these previous studies, indicating that the influence of ocular higher-order aberration on visual performance after LASIK varies depending on pupil diameter. In eyes with a larger pupil, spherical aberration caused more pronounced influence, while the impact of comalike aberration was greater in eyes with a smaller pupil.

In the present study, we evaluated the relation between changes in wavefront aberration and changes in contrast sensitivity, instead of the relation between the postoperative wavefront aberration and postoperative contrast sensitivity. It has been reported that the ocular higher-order aberration and contrast sensitivity significantly correlate with each other even in normal subjects (Takahira T, et al. IOVS 2005;46:ARVO E-Abstract 2007). Thus, to demonstrate that increases in wavefront aberrations deteriorate visual performance, the surgically induced change in wavefront aberrations and the surgically induced change in contrast sensitivity must be analyzed.

One of the weaknesses of our study is the timing of the pupil diameter measurements. We recorded pupil size before but not after surgery. There has been a report of relative mydriasis after PRK,32 whereas others have described that real pupil size is unchanged by PRK for mild to moderate refractive errors.33 Clinically, we observed the entrance pupil, which is a virtual image of the anatomic pupil. The entrance pupil is magnified and displaced anteriorly by the corneal refractive power. The relation between the real pupil (RP) and entrance pupil (EP) is described by the equation RP = EP (1 – AK/1.3375),27 where A is anterior chamber depth expressed in meters, K is the central corneal refractive power, and 1.3375 is the corneal standard refractive index. According to this equation, a reduction in K by myopia treatment leads to a decrease in clinically measured pupil diameter. When this equation is applied to a hypothetical patient, however, with RP of 4.0 mm, A of 4.0 mm, and central K of 44 D decreasing to 39 D by PRK for myopia, the EP is reduced by 0.08 mm or 1.7%—a small change that seems negligible.

The current findings appear to possess clinical relevance in the practice of excimer laser keratorefractive surgery. The recent excimer laser platforms incorporate both the eye-tracking function and the wavefront-guided treatment system. In view of the aforementioned results, patients with a larger photopic pupil will best benefit from the wavefront-guided excimer laser surgery strategy, which attempts to reduce or suppress the induction of higher-order wavefront aberrations, especially spherical aberration. In contrast, patients with a smaller pupil diameter draw a greater advantage from the eye-tracking system, so that decentration of laser ablation is minimized, leading to less induction of coma aberrations. The verification or negation of these speculations awaits future studies.


   Footnotes
 
Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Sports, and Culture of Japan (TO).

Submitted for publication August 30, 2005; revised November 1 and December 5, 2005; accepted January 26, 2006.

Disclosure: T. Oshika, None; T. Tokunaga, None; T. Samejima, None; K. Miyata, None; K. Kawana, None; Y. Kaji, None

The publication costs of this article were defrayed in part by page charge payment. This article must therefore be marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.

Corresponding author: Tetsuro Oshika, Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki, 305-8575 Japan; toshika{at}md.tsukuba.ac.jp.


   References
Top
 Abstract
 Methods
 Results
 Discussion
 References
 

  1. Oshika T, Klyce SD, Applegate RA, Howland HC, El Danasoury MA. Comparison of corneal wavefront aberrations after photorefractive keratectomy and laser in situ keratomileusis. Am J Ophthalmol. 1999;127:1–7.[CrossRef][ISI][Medline][Order article via Infotrieve]
  2. Marcos S, Barbero S, Llorente L, Merayo-Lloves J. Optical response to LASIK surgery for myopia from total and corneal aberration measurements. Invest Ophthalmol Vis Sci. 2001;42:3349–3356.[Abstract/Free Full Text]
  3. Mrochen M, Kaemmerer M, Mierdel P, Seiler T. Increased higher-order optical aberrations after laser refractive surgery; a problem of subclinical decentration. J Cataract Refract Surg. 2001;27:362–369.[CrossRef][ISI][Medline][Order article via Infotrieve]
  4. Oshika T, Miyata K, Tokunaga T, et al. Higher order wavefront aberrations of cornea and magnitude of refractive correction in laser in situ keratomileusis. Ophthalmology. 2002;109:1154–1158.[Medline][Order article via Infotrieve]
  5. Miller JM, Anwaruddin R, Straub J, Schwiegerling J. Higher order aberrations in normal, dilated, intraocular lens, and laser in situ keratomileusis corneas. J Refract Surg. 2002;18:S579–S583.[ISI][Medline][Order article via Infotrieve]
  6. Pallikaris IG, Kymionis GD, Panagopoulou SI, Siganos CS, Theodorakis MA, Pallikaris AI. Induced optical aberrations following formation of a laser in situ keratomileusis flap. J Cataract Refract Surg. 2002;28:1737–1741.[CrossRef][ISI][Medline][Order article via Infotrieve]
  7. Mok KH, Lee VW. Effect of optical zone ablation diameter on LASIK-induced higher order optical aberrations. J Refract Surg. 2005;21:141–143.[Medline][Order article via Infotrieve]
  8. Kohnen T, Buhren J, Kuhne C, Mirshahi A. Wavefront-guided LASIK with the Zyoptix 3.1 system for the correction of myopia and compound myopic astigmatism with 1-year follow-up: clinical outcome and change in higher order aberrations. Ophthalmology. 2004;111:2175–2185.[Medline][Order article via Infotrieve]
  9. Yamane N, Miyata K, Samejima T, et al. Ocular higher-order aberrations and contrast sensitivity after conventional laser in situ keratomileusis. Invest Ophthalmol Vis Sci. 2004;45:3986–3989.[Abstract/Free Full Text]
  10. Wang Z, Chen J, Yang B. Comparison of laser in situ keratomileusis and photorefractive keratectomy to correct myopia from –1.25 to –6.00 diopters. J Refract Surg. 1997;13:528–534.[ISI][Medline][Order article via Infotrieve]
  11. Pérez-Santonja JJ, Sakla HF, Alio JL. Contrast sensitivity after laser in situ keratomileusis. J Cataract Refract Surg. 1998;24:183–189.[ISI][Medline][Order article via Infotrieve]
  12. Carr JD, Stulting RD, Sano Y, Thompson KP, Wiley W, Waring GO, 3rd. Prospective comparison of single-zone and multizone laser in situ keratomileusis for the correction of low myopia. Ophthalmology. 1998;105:1504–1511.[Medline][Order article via Infotrieve]
  13. Holladay JT, Dudeja DR, Chang J. Functional vision and corneal changes after laser in situ keratomileusis determined by contrast sensitivity, glare testing, and corneal topography. J Cataract Refract Surg. 1999;25:663–669.[CrossRef][ISI][Medline][Order article via Infotrieve]
  14. Sano Y, Carr JD, Takei K, Thompson KP, Stulting RD, Waring GO, 3rd. Videokeratography after excimer laser in situ keratomileusis for myopia. Ophthalmology. 2000;107:674–684.[Medline][Order article via Infotrieve]
  15. Mutyala S, McDonald MB, Scheinblum KA, Ostrick MD, Brint SF, Thompson H. Contrast sensitivity evaluation after laser in situ keratomileusis. Ophthalmology. 2000;107:1864–1867.[CrossRef][ISI][Medline][Order article via Infotrieve]
  16. Nakamura K, Bissen-Miyajima H, Toda I, Hori Y, Tsubota K. Effect of laser in situ keratomileusis correction on contrast visual acuity. J Cataract Refract Surg. 2001;27:357–361.[CrossRef][ISI][Medline][Order article via Infotrieve]
  17. Chan JW, Edwards MH, Woo GC, Woo VC. Contrast sensitivity after laser in situ keratomileusis, one-year follow-up. J Cataract Refract Surg. 2002;28:1774–1779.[CrossRef][ISI][Medline][Order article via Infotrieve]
  18. Lee YC, Hu FR, Wang IJ. Quality of vision after laser in situ keratomileusis: influence of dioptric correction and pupil size on visual function. J Cataract Refract Surg. 2003;29:769–777.[Medline][Order article via Infotrieve]
  19. Pop M, Payette Y. Correlation of wavefront data and corneal asphericity with contrast sensitivity after laser in situ keratomileusis for myopia. J Refract Surg. 2004;20(suppl)S678–S684.[Medline][Order article via Infotrieve]
  20. Martínez CE, Applegate RA, Klyce SD, McDonald MB, Medina JP, Howland HC. Effect of pupillary dilation on corneal optical aberrations after photorefractive keratectomy. Arch Ophthalmol. 1998;116:1053–1062.[Abstract/Free Full Text]
  21. Oshika T, Klyce SD, Applegate RA, Howland HC. Changes in corneal wavefront aberrations with aging. Invest Ophthalmol Vis Sci. 1999;40:1351–1355.[Abstract/Free Full Text]
  22. Hjortdal JØ, Olsen H, Ehlers N. Prospective randomized study of corneal aberrations 1 year after radial keratotomy or photorefractive keratectomy. J Refract Surg. 2002;18:23–29.[Medline][Order article via Infotrieve]
  23. Wang Y, Zhao K, Jin Y, Niu Y, Zuo T. Changes of higher order aberration with various pupil sizes in the myopic eye. J Refract Surg. 2003;19(2 suppl)S270–S274.[Medline][Order article via Infotrieve]
  24. Hernández C, Domenech B, Seguí MM, Illueca C. The effect of pupil and observation distance on the contrast sensitivity function. Ophthalmic Physiol Opt. 1996;16:336–341.[CrossRef][ISI][Medline][Order article via Infotrieve]
  25. Strang NC, Atchison DA, Woods RL. Effects of defocus and pupil size on human contrast sensitivity. Ophthalmic Physiol Opt. 1999;19:415–426.[CrossRef][ISI][Medline][Order article via Infotrieve]
  26. Haw WW, Manche EE. Effect of preoperative pupil measurements on glare, halos, and visual function after photoastigmatic refractive keratectomy. J Cataract Refract Surg. 2001;27:907–916.[Medline][Order article via Infotrieve]
  27. Freedman KA, Brown SM, Mathews SM, Young RS. Pupil size and the ablation zone in laser refractive surgery: considerations based on geometric optics. J Cataract Refract Surg. 2003;29:1924–1931.[Medline][Order article via Infotrieve]
  28. Wachler BS, Hiatt D, Chou B, Christie JP. Reduction of pupil size and halos with minus lenses after laser in situ keratomileusis. J Refract Surg. 2004;20:149–154.[Medline][Order article via Infotrieve]
  29. Helgesen A, Hjortdal J, Ehlers N. Pupil size and night vision disturbances after LASIK for myopia. Acta Ophthalmol Scand. 2004;82:454–460.[Medline][Order article via Infotrieve]
  30. Twa MD, Bailey MD, Hayes J, Bullimore M. Estimation of pupil size by digital photography. J Cataract Refract Surg. 2004;30:381–389.[Medline][Order article via Infotrieve]
  31. Applegate RA, Howland HC, Sharp RP, Cottingham AJ, Yee RW. Corneal aberrations and visual performance after radial keratotomy. J Refract Surg. 1998;14:397–407.[ISI][Medline][Order article via Infotrieve]
  32. Geerling G, Neppert B, Wirbelauer C, Laqua H. Relative mydriasis after photorefractive keratectomy. J Refract Surg. 2000;16:69–74.[Medline][Order article via Infotrieve]
  33. Spadea L, Giammaria D, Ferrante R, Balestrazzi E. Pre-excimer laser and post-excimer laser refractive surgery measurements of scotopic pupil diameter using 2 pupillometers. Ophthalmology. 2005;112:1003–1008.[Medline][Order article via Infotrieve]



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