|Year : 2020 | Volume
| Issue : 2 | Page : 90-100
Supracor LASIK treatment of hyperopic and myopic presbyopes: a comparative study
Basem M Ibrahim
Department of Ophthalmology, Faculty of Medicine, Zagazig University, Zagazig, Egypt
|Date of Submission||28-Dec-2019|
|Date of Decision||24-Jan-2020|
|Date of Acceptance||20-Feb-2020|
|Date of Web Publication||26-Jun-2020|
MD Basem M Ibrahim
Department of Ophthalmology, Faculty of Medicine, Zagazig University, Zagazig 44519
Source of Support: None, Conflict of Interest: None
Background Supracor is a relatively new technique that has been approved for hyperopic presbyopia correction; however, till now, no published studies have evaluated the performance of supracor in myopic patients with presbyopia.
Objective The aim of this study was to compare the results of supracor treatment of presbyopia between hyperopic and myopic patients.
Patients and methods The study included two groups: hyperopic group and myopic group. Complete preoperative examination consisted of cycloplegic and manifest refraction, spherical equivalent (SE), binocular uncorrected and corrected distant visual acuity (UCDVA and CDVA), binocular uncorrected and corrected near visual acuity (UCNVA and CNVA), measurement of higher order aberrations, and the determination of the dominant eye using hole-in-the card test. Patients were examined at the first day, third day, 1 month, 3 months, and 6 months postoperatively. UCDVA, CDVA, UCNVA, CNVA, higher order aberrations, and SE were measured, and all complications were recorded. Furthermore, patient’s satisfaction was documented by a detailed questionnaire. All data were collected, analyzed, and compared between the two groups.
Results The study included 20 hyperopic and 19 myopic patients. There were no statistically significant differences (P>0.05) between the two groups regarding postoperative UCDVA, CDVA, UCNVA, CNVA, SE, spherical aberrations, and complications. However, there was a statistically significant difference (P<0.05) between the studied groups regarding patient satisfaction at 1 month, 3 months, and 6 months postoperatively (which was higher in patients with hyperopia), with a significant increase in patient satisfaction in those with hyperopia over time.
Conclusion Supracor was found to be effective, predictable, and stable technique in the management of presbyopia in both patients with myopia and those with hyperopia, with similar results in the two groups except for patient satisfaction, which was higher in those with hyperopia.
Keywords: hyperopia, myopia, presbyopia, supracor
|How to cite this article:|
Ibrahim BM. Supracor LASIK treatment of hyperopic and myopic presbyopes: a comparative study. Delta J Ophthalmol 2020;21:90-100
|How to cite this URL:|
Ibrahim BM. Supracor LASIK treatment of hyperopic and myopic presbyopes: a comparative study. Delta J Ophthalmol [serial online] 2020 [cited 2020 Sep 22];21:90-100. Available from: http://www.djo.eg.net/text.asp?2020/21/2/90/287466
| Introduction|| |
Presbyopia is an age-related process that is characterized by inability to bring near objects into focus. This process is attributed to changes in the parts of the visual system concerned with accommodation. Presbyopia starts to show itself by the age of 40–45 years .
Various surgical refractive procedures have evolved in the past few years to face the problem of presbyopia, including monovision laser in situ keratomileusis (LASIK), the IntraCor technique, conductive keratoplasty, photorefractive keratectomy (PRK), corneal inlay, and multifocal cornea . Corneal multifocality (presbyopic LASIK, presbyLASIK) for correction of presbyopia has been evolving since McDonnell and Moreira reported improvement of near vision after radial keratotomy and LASIK ,. Many of these procedures are capable of treating most of the refractive errors simultaneously with presbyopia, and this was documented by several published studies such as the studies on monovision in both patients with myopic and hyperopic presbyopia ,, presbyMAX for patients with myopic and hyperopic presbyopia ,, and PRK for myopic presbyopia group . The latter can enhance the near acuity in patients with myopic presbyopia by the induced corneal aberrations through multifocal effect.
Supracor is one of these refractive multifocal procedures that have been recently evolved to face the refractive surgeon’s problems in treating both refractive errors and presbyopia at the same time. It performs an aspheric ablation profile with central ablation for near vision and a paracentral ablation for distance vision (multifocal corneal profile with central myopia), so a good focus is allowed over a wide range of distances ,.
Supracor (Technolas Excimer Workstation 217 P) is a relatively new technique that has been approved since May 2011 for hyperopic presbyopia correction ,. However, till now, there are no published studies that have evaluated the performance of supracor excimer laser treatment in myopic patients with presbyopia. Therefore, this study aimed to evaluate the efficacy of supracor in treating presbyopia in patients with different refractive errors and to compare the results of the supracor treatment of presbyopia between hyperopic and myopic patients.
| Patients and methods|| |
This is a prospective, interventional, comparative case series between hyperopic and myopic patients with presbyopia. Thirty nine patients (20 patients with hyperopia and 19 patients with myopia) were included in the study in the period between May 2018 and August 2019 at the Rowad Eye Centre, Zagazig, Egypt.
The study protocol was approved by the Local Ethical Committee of the Rowad Eye Centre. After a complete ophthalmic examination and a thorough discussion of the risks and benefits of the surgery, all patients signed a written informed consent to participate in the study and for publication of data before enrollment in the study.
The study included patients with a refraction between −8.0 and +4.0 D of spherical error, astigmatism not more than +2.0 D in hyperopia and −4.0 D in myopia with a maximum difference between cycloplegic and manifest refraction of 0.75 D, corrected distant visual acuity (CDVA) of both eyes more than or equal to 0.8 (decimal scale), near addition required more than or equal to 1.75 D, keratometric (K) readings between 41 and 45 D, angle kappa more than 10°, photopic pupil size less than 3 mm and mesopic pupil size more than 6 mm, suitable corneal topography for LASIK, and age more than or equal to 47 years in those with hyperopia and more than or equal to 42 years in those with myopia.
Patients with active ophthalmic disease, cataract or other medial opacities, uveitis, glaucoma, corneal irregularity, keratoconus, posterior segment abnormality, prior ophthalmic surgery, emmetropic patients, nearly emmetropic patients (SE≤±1 D), and patients with corneal thickness less than 480 µm or residual stromal bed less than 280 µm, were excluded from the study. Patients who were pregnant, breastfeeding, or had systemic disease(s) or taking topical or systemic drugs that may delay healing were also excluded from the study.
Selected patients were divided according to their error of refraction into two groups: hyperopic group and myopic group.
Complete preoperative examination consisted of cycloplegic refraction, manifest refraction, spherical equivalent (SE), uniocular and binocular uncorrected distant visual acuity (UCDVA) and CDVA, and uniocular and binocular uncorrected and corrected near visual acuity (UCNVA and CNVA) at 40 cm. We used the standard equivalent Snellen acuities for distance vision combined with the decimal near vision optotype scale (equivalent to early treatment diabetic retinopathy study format near vision chart 3) for near vision. Distant vision was tested in normal day light to avoid refractive mistakes related to pupil size, whereas near vision was tested in bright light at a distance of 40 cm. Intraocular pressure measurements using applanation tonometry, slit-lamp bio-microscopy, and fundoscopy were done for all cases.
Corneal topography and pachymetry were performed using Orbascan (Bausch+Lomb Technolas, München, Germany). Mesopic pupil diameter and higher order aberrations were measured using ZYWAVE 3 (Technolas Perfect Vision, GmbH, software version 1.9.1214.2; Bausch+Lomb). The dominant eye (DE) was determined using hole-in-the card test, where the patient held a card with an aperture in it and viewed a distant target through the hole. Then each eye was occluded alternately to establish which eye was aligned with the hole and the target. The selected eye was considered the DE.
Topical anesthesia (benoxinate hydrochloride 0.4%, Benox, E.I.P.I. Co., 10th of Ramadan, Egypt) was applied, followed by povidone–iodine 10% application to the skin and 5% to the conjunctiva. Then a sterile surgical drape and a speculum for the eye lids were applied.
A 120-µm thick flap with a diameter more than or equal to 9 mm was raised using an automated microkeratome; Moria M2 (Moria, Antony, France). The stromal bed was dried with a sponge and the ablation was done to a fixed 6 mm optical zone in all cases using Technolas excimer laser (TENEO 317; Technolas Perfect Vision GmbH, Montpellier, Germany). An infrared pupillary eye tracker was used.
Supracor mix strategy (hybrid technique) was used where mild addition of +1.5 D was given in the DE with a zero postoperative target refraction, whereas regular addition of +2.5 and −0.5 D postoperative target refraction was given in the non-DE (reduced multifocality in distance eye combined with full multifocality and monovision in the near eye).
The stroma was rinsed with balanced salt solution followed by flap repositioning with application of antibiotic eye drops (moxifloxacin) at the end of the procedure.
All patients were instructed to apply moxifloxacin and prednisolone acetate 1% eye drops and preservative free artificial tears for a week.
Patients were examined at the first day, third day, 1 month, 3 months, and 6 months postoperatively. Uniocular and binocular UCDVA, CDVA, UCNVA, CNVA, and SE were measured at all visits. In this study, binocular visual acuity was used in comparison, in general, because we used supracor mix strategy with asymmetric near addition and asymmetric target refraction in each eye. So, binocular visual acuity was more relevant in comparison between groups than the uniocular one. Corneal topography and aberration profile were done at 1-month, 3-month, and 6-month visits only. All complications in the two groups were recorded.
Moreover, patient’s satisfaction was documented by a questionnaire including satisfaction in terms of near vision, distant vision, night glare, dependence on correction (eyeglasses or contact lenses), general appearance after surgery (without glasses), and overall satisfaction. Patients were asked to grade each question on a scale from 0 to 100%, where 0% indicated not satisfied at all and 100% indicated completely satisfied. Patients were asked to fill out the same questionnaire at 1 month, 3 months, and 6 months postoperatively.
Predictability of refraction (deviation of SE from zero refraction), stability of refraction (changes in SE at 1 month, 3 months, and 6 months), and efficacy index of vision (ratio of postoperative UCDVA and UCNVA at the end of follow up: preoperative CDVA and CNVA) were calculated.
Data analysis was performed using the software Statistical Package for the Social Sciences (version 20; SPSS Inc., Chicago, Illinois, USA). Quantitative variables were described using mean and SD. Categorical variables were described using absolute frequencies and were compared using c2 test and Fisher exact test when appropriate. Kolmogorov–Smirnov (distribution type) and Levene (homogeneity of variances) tests were used to verify assumptions for use in parametric tests. To compare the means of the two groups, Mann–Whitney test (for non-normally distributed data) was used to compare medians of the two groups and independent sample t test (for normally distributed data) was used to compare the means of the two groups. To compare the change in one group over time, repeated measure analysis of variance and Friedman test for normally and not normally distributed data were used, respectively. The level of statistical significance was set at 5% (P<0.05). Highly significant difference was present if P value less than or equal to 0.001.
| Results|| |
The mean age of the patients was 55.35±7.68 years (range, 46–69 years) in the hyperopic group and 52.74±9.94 years (range, 42–70 years) in the myopic group. There were 13 (65%) male patients and seven (35%) female patients in the hyperopic group and 10 (52.6%) male patients and nine (47.4%) female patients in the myopic group. There was no statistically significant difference between the studied groups regarding age or sex.
Regarding the binocular UCDVA, there was a significant change from the preoperative level in relation to the postoperative level in each group, but there was no significant difference between the two groups regarding postoperative binocular UCDVA at 1 month, 3 months, or 6 months ([Table 1] and [Figure 1]).
|Table 1 Comparison between the studied groups regarding binocular uncorrected distant visual acuity|
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|Figure 1 Binocular uncorrected distant visual acuity values overtime among the studied groups. UCDA, uncorrected distant visual acuity.|
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There was no significant difference between the preoperative and postoperative binocular CDVA in each group. In addition, there was no significant difference in binocular CDVA between the two groups ([Figure 2]).
|Figure 2 Binocular preoperative and postoperative corrected distant visual acuity values among the studied groups. CDVA, corrected distant visual acuity.|
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Regarding the binocular UCNVA, there was a significant change from the preoperative level in relation to the postoperative level in each group, but there was no significant difference between the two groups in the postoperative binocular UCNVA at 1 month, 3 months, or 6 months ([Table 2] and [Figure 3]).
|Table 2 Comparison between the studied groups regarding binocular uncorrected near visual acuity|
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|Figure 3 Binocular preoperative and postoperative uncorrected near visual acuity values among the studied groups. UNVA, uncorrected near visual acuity.|
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There was no significant difference between the preoperative and postoperative binocular CNVA in each group. In addition, there was no significant difference in binocular CNVA between the two groups whether preoperatively or postoperatively ([Figure 4]).
|Figure 4 Binocular preoperative and postoperative corrected near visual acuity values among the studied groups. CNVA, corrected near visual acuity.|
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There was no significant difference between both groups regarding SE at 1 day, 1 month, 3 months, and 6 months, postoperatively. Regarding each group individually, there was a significant difference between preoperative SE and its value at any point postoperatively ([Table 3]).
|Table 3 Comparison between the studied groups regarding spherical equivalent|
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There was no statistically significant difference between groups regarding higher order aberrations preoperatively and at 1 month, 3 months, and 6 months, postoperatively. Regarding each group individually, there was a significant increase in higher order aberrations after surgery ([Table 4] and [Figure 5]).
|Table 4 Comparison between the studied groups regarding higher order aberrations|
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|Figure 5 Preoperative and postoperative high order aberration values among the studied groups.|
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There was no statistically significant difference between the studied groups regarding postoperative complications ([Table 5]). One of the hyperopic patients and three of the myopic patients had macrostriae, which were managed by removing the flap epithelium, flap elevation, repositioning, and drying. On follow-up visits, there was delayed epithelial healing for 3 weeks in one case with mild haze for 5 weeks thereafter. All cases with disseminated lamellar keratopathy were limited and peripheral. They required no further interference except for one progressive case which required flap elevation and wash.
|Table 5 Comparison between the studied groups regarding postoperative complications|
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Regarding regression, four (20%) of the hyperopic patients showed regression of UCNVA of two lines in one or two eyes, whereas one (10.5%) myopic patient showed regression in UCDVA of two lines in the two eyes, and all of them improved by glasses. Re-do operation was done for all of them at the end of the third postoperative month; four of them regained the lost acuity, whereas one (5%) hyperopic patient did not improve. There was no statistically significant difference between the studied groups regarding regression ([Table 6]).
There was a statistically significant difference between the studied groups regarding patient satisfaction at 1 month, 3 months, and 6 months (with higher satisfaction in patients with hyperopia). There was also a significant increase in patient satisfaction in patients with hyperopia over time, whereas there was no significant change in satisfaction over time in patients with myopia ([Table 7] and [Figure 6]).
|Table 7 Comparison between the studied groups regarding patient satisfaction|
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Regarding efficacy index, supracor was proven to be effective whether in far or near vision in the two groups (for far vision 0.942±0.093 in patients with hyperopia and 0.914±0.081 in patients with myopia, whereas for near vision, it was 1.078±0.094 in patients with hyperopia and 1.029±0.081 in patients with myopia), with no significant difference between them ([Figure 7]).
Regarding predictability, supracor was proven to be predictable in the two groups (−0.0863±0.425 in patients with hyperopia and −0.0197±0.425 in patients with myopia at the 6-month follow-up visit), with no significant difference between them ([Figure 8]).
Regarding stability of the refraction after surgery, there was no significant change over time within each group (P=0.098 in the hyperopic group and 0.116 in the myopic group, [Figure 9]).
|Figure 9 Stability of refraction at 1, 3 and 6 months postoperatively among both groups.|
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| Discussion|| |
Surgical correction of presbyopia is considered as one of the most challenging aspects of refractive surgery.
PresbyLASIK was first described by Ruiz in 1996. It could be achieved by shaping a multifocal cornea over a 6-mm zone . Supracor is considered a central presbyLASIK technique which is pupil dependent. It seeks for improving both distant and near vision. It is a relatively new corneal approach for presbyopia treatment which was approved for hyperopia since 2011 .
Many studies have proved the effectiveness and safety of supracor in the management of presbyopia in hyperopic patients ,. However, till now, there are no published studies to evaluate the supracor efficacy in myopia and to compare it to hyperopia.
In this study, we evaluated the efficacy and safety of supracor in correcting presbyopia associated with either hyperopia or myopia and compared the results in the two categories.
We used asymmetrical supracor strategy for both hyperopic and myopic presbyopia where the DE was targeted to emmetropia and the non-DE to −0.50 D with asymmetric near addition in each eye. That is why we used binocular visual acuity rather than the uniocular one in the comparison between the two groups as the association between the two eyes in this case is crucial for best vision whether for far or near. This mix strategy was recommended by Tomás et al. . They reported that asymmetrical supracor LASIK for patients with hyperopic presbyopia considerably improved distance and near UCVA, while eliminating or decreasing spectacle dependence for far or near vision and concluded that asymmetrical supracor was safe, effective, and predictable for patients with hyperopic presbyopia. In our experience, we should stress that the supracor asymmetric strategy is not suitable for all cases and that the relative decrease of binocular vision which may occur in far or near is hazardous for certain jobs, for example, drivers, pilots, surgeons, and others. Precise case selection, proper patient motivation, and clear expectation are all essential factors for successful and satisfying outcomes.
The present study showed that supracor was safe and effective in managing presbyopia in both hyperopic and myopic patients with minor differences between the two groups. The postoperative binocular UCDVA, CDVA, UCNVA, CNVA, and SE results showed no statistically significant difference between the two groups at 1 month, 3 months, and 6 months, postoperatively, whereas there were statistically significant differences regarding the UCDVA and the UCNVA when compared with the preoperative levels. In contrast, Baudu et al. , in their study for treating presbyopic patients, using another bi-aspheric ablation profile (presbyMAX module), reported different results between myopic and hyperopic patients. They reported that the results for the myopic cases were better regarding postoperative SE, binocular UCNVA, distance corrected near visual acuity (DCNVA), and CDVA as the preoperative myopes showed 0.2 lines better in both UCNVA and DCNVA and one letter better in CDVA. These differences were statistically significant.
Three (23.1%) of the hyperopic patients, in the present study, showed regression of near acuity of two lines, whereas one (8.3%) myopic patient showed regression in distant acuity of two lines. There was no statistically significant difference between the two groups in this aspect. Re-do operation was done for all of them at the third postoperative month; three of them regained the lost acuity at the 6th month visit, whereas one (7.7%) hyperopic patient did not improve. Nearly most studies on presbyopic correction surgeries reported a varying degree of regression and retreatment such as the studies on monovision (15%) , laser blended vision (19%) , multifocal ablations (28%) , supracor (13%)  and presbyMAX (14%) .
In the present study, all complications were managed successfully with no statistically significant differences between the two groups. Two of the myopic patients had macrostriae, which were managed at the time of diagnosis, but there was delayed epithelial healing, after de-epithelisation of the flap, for 3 weeks in one case with mild haze for 5 weeks thereafter. This may be attributed to the old age (67 years) of the patient.
Patient satisfaction gained considerable interest in many studies on presbyopic surgeries, and variable percentages of patient satisfaction were reported according to the type of surgery. For example, the studies on monovision reported variable results of patient satisfactions that ranged from 86% , 92%  up to 96% , whereas the study on intracorneal multifocality reported 98% patient satisfaction , and the study on supracor by Ryan and O’Keefe , reported 96% patient satisfaction.
The only statistically significant difference between the hyperopic and the myopic supracor in this study was patient satisfaction. The overall patient satisfaction was higher in the hyperopic group compared with the myopic group in all postoperative visits and increased over time to reach a value of 91.23±2.95% in patients with hyperopia and 83±2.13% in patients with myopia at the 6-month follow-up visit. Jackson et al. , reported in their study on multifocal ablation with central myopia that patients who had a larger amount of preoperative hyperopia or a greater decrease of preoperative DCNVA were more likely to have overall satisfaction.It was noticed that the higher order aberrations increased after supracor at the 6-month follow-up visit. It was 0.49±0.11 in the hyperopic group and 0.52±0.12 in the myopic group compared with the preoperative values of 0.36±0.14 and 0.35±0.13, respectively. The increase in the higher order aberrations actually helps in increasing the depth of focus, and as a consequence enhanced the presbyopia treatment. This concept regarding the benefit of increasing the higher order aberrations is well documented in other studies on surgical treatment of presbyopia such as the study on conductive keratoplasty , the studies on multifocal cornea ,,, and the study on PRK in myopia .
The efficacy index, predictability, and stability of the results were calculated, and supracor was found to be effective and predictable with stable results in both patients with hyperopia and those with myopia, with no significant difference between them.
| Conclusion|| |
Supracor is an effective, predictable, and stable technique in the management of presbyopia in both patients with hyperopia and those with myopia, with similar results in the two groups, except for patient satisfaction, which was significantly higher in patients with hyperopia. Further studies are needed to evaluate supracor in myopia with longer follow-up to confirm its continuous stability.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]