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Refractive outcomes of femtosecond laser–assisted secondary arcuate incisions in patients with residual refractive astigmatism after trifocal intraocular lens implantations
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ARTICLE
Refractive outcomes of femtosecond laser–assisted secondary arcuate incisions in patients with residual refractive astigmatism after trifocal intraocular lens implantations Inger L€ udeke, MD, Johannes Gonnermann, MD, Jørn Jørgensen, MD, Thomas Neuhann, MD, Keith McKay, BSc Optom, Mathias Fleischer, MD, Peter Galambos, MD, Ralf-Christian Lerche, MD
Purpose: To evaluate the refractive and visual outcomes of arcuate incisions performed with the femtosecond laser in patients with a residual refractive astigmatism after refractive lens exchange (RLE) with trifocal intraocular lenses (IOLs). Setting: EuroEyes Clinical Group, Hamburg, Germany. Design: Retrospective interventional case series. Methods: Pseudophakic patients with remaining refractive astigmatism after RLE with a trifocal IOL were treated with femtosecond laser–assisted corneal arcuate incisions. Patients who had a previous corneal treatment were excluded. Outcome measures were uncorrected (UDVA) and corrected distance visual acuities, manifest refraction, and a power vector analysis.
Results: The study enrolled 95 eyes of 70 patients. The mean follow-up was 5.6 months G 4.9 (SD). Constructing an
P
atient satisfaction with multifocal intraocular lenses (IOLs) is highly dependent on a precise emmetropic refraction outcome. This requires the correction of preexisting astigmatism, either with toric IOLs or with lower astigmatism, by carefully choosing the incision site in the steep axis. Despite good surgical planning and performance, residual astigmatism might occur. Astigmatisms greater than 0.50 diopter (D) could result in unsatisfactory outcomes.A There are different methods for correcting preexisting and/or residual astigmatism after cataract surgery. Manually performed arcuate incisions or limbal relaxing
astigmatic power vector (APV) with Jackson cross-cylinder axes at 180 degrees and 90 degrees and Jackson crosscylinder axes at 45 degrees and 135 degrees, the mean preoperative vector length was 0.46 G 0.16 diopter (D). The mean postoperative APV was 0.17 G 0.16 D. This difference was statistically significant (P < .001). The difference between the UDVA preoperatively (0.17 G 0.15) and postoperatively (0.08 G 0.10) was statistically significant (P < .001). No intraoperative or postoperative complications were observed.
Conclusion: Femtosecond laser–assisted corneal arcuate incisions were safe, efficient, and feasible to reduce refractive astigmatism after trifocal IOL implantation. J Cataract Refract Surg 2018; -:-–- Q 2018 ASCRS and ESCRS Published by Elsevier Inc
incisions1–5 as well as the classic ablative procedures such as photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) are widely performed.1–4 Disadvantages of manually performed arcuate incisions are low predictability and the risk for perforation.3–5 Laser in situ keratomileusis enhancements result in good refractive results but can lead to neurotrophic problems and dry-eye syndrome with decreased visual acuity, especially in older patients.1–5 With the introduction of the femtosecond laser into corneal and cataract surgeries, new possibilities have arisen for the precision of incisional correction of astigmatism.
Submitted: September 13, 2017 | Final revision submitted: August 6, 2018 | Accepted: August 9, 2018 Universit€atsmedizin Berlin €deke, Gonnermann, Jørgensen, Neuhann, McKay, Fleischer, Galambos, Lerche), Hamburg, Charite From the EuroEyes Clinical Group (Lu (Gonnermann), Department of Ophthalmology, Berlin, MVZ Prof. Neuhann (Neuhann), Munich, and Universit€atsklinikum Hamburg-Eppendorf (Lerche), Department of Ophthalmology, Hamburg, Germany. €deke and Gonnermann contributed equally to this work. Drs. Lu €deke, MD, EuroEyes Clinical Group, Ophthalmology, Valentinskamp 90, Hamburg 20355, Germany. Email: [email protected]. Corresponding author: Inger Lu Q 2018 ASCRS and ESCRS Published by Elsevier Inc.
0886-3350/$ - see frontmatter https://doi.org/10.1016/j.jcrs.2018.08.024
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REFRACTIVE OUTCOMES OF FEMTOSECOND-LASER ARCUATE INCISIONS
Nowadays, corneal arcuate incisions are regularly performed with the femtosecond laser, and they are commonly used to reduce corneal astigmatism during femtosecond laser–assisted cataract surgery,6 but also as a standalone procedure in patients with remaining astigmatism after keratoplasty or cataract surgery.7–10 Advantages of femtosecond laser–assisted arcuate incisions are higher accuracy and reproducibility of the length, the depth, the inclination, and the optical zone (OZ) diameter of the arcuate incisions as well as the unique possibility of offering the option to not penetrate the outer surface of the cornea but performing them wholly intrastromally.1–4 In this study, we evaluated the refractive outcomes of epithelium-penetrating femtosecond laser–assisted arcuate keratotomy in patients with residual refractive astigmatism after the implantation of trifocal IOLs as an alternative to other refractive secondary surgeries such as touch-up LASIK or add-on IOLs. PATIENTS AND METHODS Study Design This study is a retrospective analysis of all consecutive patients who had femtosecond laser–assisted keratotomy after implantation of a trifocal IOL (AT LISA tri 839MP or AT LISA tri toric 939MP, both Carl Zeiss Meditec AG) in the EuroEyes Clinical Group in Hamburg, Germany, from January 1, 2014 to October 31, 2015. The study was conducted in accordance with the tenets of the Declaration of Helsinki. All patients signed a written informed consent form before the surgery. Inclusion criteria were a spherical equivalent (SE) within G0.5 D and an astigmatism by subjective refraction greater than or equal to 0.5 D. Eyes that had a corneal refractive treatment before the implantation of an artificial lens, eyes that had a refractive enhancement before the arcuate incision, and eyes with an irregular corneal astigmatism were excluded. All patients underwent a preoperative ophthalmic examination including uncorrected (UDVA) and corrected (CDVA) distance visual acuities, autorefraction, slitlamp biomicroscopy, dilated fundoscopy, and high-resolution rotating Scheimpflug imaging (Pentacam HR, Oculus Optikger€ate GmbH) with keratometry, topography, and pachymetry. Postoperative examinations, which included UDVA and CDVA, autorefraction, and slitlamp biomicroscopy, were scheduled for the first day, then 1 week, 1 month, and 3 months later. Surgical Technique The arcuate incisions were performed by one of two experienced surgeons (J.J. and R.C.L.) between January 1, 2014 and October 31, 2015. All procedures were performed under topical anesthesia with a femtosecond laser (Lensx, Alcon Laboratories, Inc.). The astigmatic treatment was based alone on the subjective refraction. Keratometric (K) values were collected but had no impact on the calculation of the incision parameters made with the treatment nomogram (Table 1). The arcuate incisions were performed using the following settings. A paired reference point at the temporal limbus (0- to 180-degree) was marked using a pendular marker (Gerten Corneal Pendulum Marker, Geuder AG) while the patient was in an upright position. The depth of the incision was set at 80% of the corneal thickness with a 90-degree side-cut angle. The OZ diameter was aimed at 8.0 mm. The incisions were created with a programmed energy setting of 3.0 mJ and a spot/line separation of 4 4 mm. After the laser surgery, the incisions were opened manually. Postoperatively, antibiotics (Floxal edo eyedrops 3 mg/ml, 4 times a day) and lubrication eyedrops were prescribed for 1 week. Volume - Issue - - 2018
Table 1. Study authors’ nomogram (modified from a Woodcock nomogramB). K Value (D)
Incision, Number ( )
%0.75 %1.00 %1.25 %1.50 %2.0 %2.5
1 (45) 2 (44 each) 2 (44 and 45) 2 (45 each) 2 (47 each) 2 (49 each)
K Z keratometry
The SPSS Statistics for Windows software package (version 21.0, IBM Corp.) was used for statistical analysis. The Kolmogorov-Smirnov test was used to check the normality of the data distribution. When parametric analysis was possible, the paired Student t test was performed for all parameter comparisons between preoperative and postoperative examinations as well as between consecutive postoperative visits. Otherwise, when parametric analysis was not possible, the Wilcoxon rank-sum test was applied to assess the significance of differences between consecutive examinations. In all cases, a P value less than 0.05 was considered statistically significant. Vector Analysis The astigmatic value was described using the power vector analysis: If the spherical power is removed, the result is a Jackson crossed-cylinder with axes at 90 degrees and 180 degrees (J0), and a Jackson crossed-cylinder with axis at 45 and 135 degrees (J45). The following formulas for calculating the vector lengths were used: J0 Z ðC=2Þcosð2aÞ; and J45 Z ðC=2Þsinð2aÞ with C for the cylindric value with C O 0 for C cyl and C ! 0 for cyl form. Astigmatic power vector ðAPVÞ Z root ðJ02 þ J452 Þ and B Z root ðM2 þ J02 þ J452 Þ with B indicating the overall blurring strength including the spherical and cylindric values and M indicating the power of a lens that is equal to the SE.11
RESULTS The study analyzed 95 eyes of 70 patients (43 women, 27 men). The mean age was 55 years G 8 (SD). The level of refractive astigmatism ranged from 0.5 to 2.25 D. The mean K values were 42.67 G 1.97 D in the flat axis and 43.71 G 2.09 D in the steep axis. The primary corneal astigmatism before refractive lens exchange (RLE) ranged from 0 to 6.4 D. Fifty-nine eyes (62.1% had astigmatism of 1.0 D or less, 28 eyes (29.5%) had astigmatism between greater than 1.0 D and 2 D or less, 5 eyes (5.2%) were between greater than 2.0 D and 3 D or less, and 3 eyes (3.2%) had astigmatism greater than 3.0 D. The mean corneal astigmatism was 1.05 G 0.94 D. The femtosecond-assisted keratotomy was performed 3 months after the initial RLE at the earliest (mean 7.0 G 3.4 months; range 3 to 37 months). Table 2 shows the preoperative characteristics of the patient population. Preoperatively, the mean SE was 0.07 G 0.38 D, the vector J0 was 0.24 G 0.33 D, and
REFRACTIVE OUTCOMES OF FEMTOSECOND-LASER ARCUATE INCISIONS
Table 2. Patient characteristics preoperatively. Parameter Sex Male Female Eyes Right Left IOL type Spheric Toric Astigmatism (D) 0.5 0.75 1.0 1.25–1.50 1.75–2.25
Number of Eyes (%) 51 (53.6) 44 (46.4) 46 (48.4) 49 (51.6) 63 32
(66) (34)
13 (13.7) 34 (35.8) 28 (29.5) 18 (18.9) 2 (2.1)
IOL Z intraocular lens
the vector J45 was 0.03 G 0.28 D. Constructing an APV with J0 and J45, the mean preoperative vector length was 0.46 G 0.16 D. The mean overall blurring strength B was 0.58 G 0.23 D. Figure 1 shows the preoperative refractive astigmatic components (J0 and J45). After a mean follow-up of 6 G 5 months, the mean postoperative SE was 0.05 G 0.35 D. The difference between the preoperative and postoperative values was not statistically significant (P Z .553). The mean postoperative vector J0 was 0.06 G 0.17 D. The difference between the preoperative and postoperative values was statistically significant (P ! .001). The mean postoperative vector J45 was 0.00 G 0.15 D. The difference between the preoperative and postoperative values was not statistically significant (P Z .290). The mean postoperative astigmatic power vector was 0.17 G 0.16 D. The difference between the preoperative and postoperative astigmatic power vectors was statistically significant (P ! .001). The mean postoperative overall blurring strength B was 0.35 G 0.23 D. The difference between the preoperative and postoperative values was statistically significant (P ! .001). To investigate the stability of the refraction during the follow-up period, the results after 1 week and at the last follow-up (6 G 5 months) were evaluated. The SE after 1 week was 0.05 G 0.33 D and showed no statistically significant difference from the last follow-up visit (P Z .738). The vector J0 (0.04 G 0.18 D) and vector J45 (0.02 G 0.13 D) after 1 week were not significantly different from the postoperative values after 6 months (P Z .217 and P Z .300, respectively). Finally, the astigmatic power vector was 0.15 G 0.16 after 1 week and remained stable over the follow-up period (P Z .327). Figure 2 shows the postoperative values. The postoperative values are closer to the origin than the preoperative values, which show a more scattered picture.
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The CDVA in logarithm of the minimum angle of resolution (logMAR) was 0.02 G 0.05 preoperatively compared with 0.03 G 0.07 postoperatively (P Z .759). The UDVA in logMAR improved significantly from 0.17 G 0.15 preoperatively to 0.08 G 0.10 postoperatively (P ! .001). The mean safety index (CDVA preoperatively/ CDVA postoperatively) was calculated with 1.0 and the mean efficacy index (UDVA postoperatively/CDVA preoperatively) with 0.89. Table 2 shows the preoperative astigmatism of the study eyes. Postoperatively, 51 eyes (53.7%) had a residual astigmatism of 0 to 0.25 D, 28 eyes (29.5%) had 0.5 D left. Overall, 79 eyes (83.2%) were within G0.5 D astigmatism postoperatively. Two eyes were overcorrected with a refractive astigmatism of 0.5 D or more in an axis between 60 and 120 degrees away from the original axis. The first eye’s refractive value was 0.75 1.0 102 preoperatively and resulted in 0.25 0.50 38 postoperatively. The second eye’s refractive value was 0.5 1.0 175 before surgery and 0.75 1.0 112 postoperatively. Fifty-two (74.7 %) of the 70 patients were satisfied with the postoperative result. Ten (10.5%) of the 95 eyes received an additional enhancement either with LASIK (5 eyes), PRK (1 eye), or a further femtosecond laser–assisted arcuate incision (4 eyes) (Tables 3 and 4). No intraoperative or postoperative events, such as perforation or infection, were observed. DISCUSSION The purpose of this retrospective study was to evaluate the refractive and visual outcomes after epithelium-penetrating femtosecond laser–assisted arcuate incisions in patients with remaining astigmatism after implantation of a trifocal IOL. The demand for a precise emmetropic outcome is especially high after implantation of multifocal lenses. From the literature, we know that postoperative astigmatism is an important issue for the outcome of lens surgery. A postoperative residual astigmatism greater than 0.50 D can lead to blurry vision and therefore to patient dissatisfaction.A Compared with higher grades of astigmatism, relaxing incisions seem to be a helpful tool in lower post-surgical astigmatism. After performing experimental cadaver trials, Duffey et al.12 concluded that arcuate incisions are ideal for mixed astigmatism. In the steep axis, the cornea experiences a myopic shift, whereas the flat axis becomes steeper to a lower degree. This is known as the coupling effect. In the present study, arcuate incisions were primarily used in patients with a mixed astigmatism. The mean preoperative SE was 0.07 G 0.38 D. The mean postoperative SE was 0.05 G 0.35 D. The stability of the SE reflects the coupling effect and seems to be also suitable for arcuate incisions based on the refraction alone. With this refractive preselection, good refractive and visual results are obtained with arcuate incisions created with the femtosecond laser in patients with multifocal IOLs. Volume - Issue - - 2018
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Figure 1. Preoperative plot of J0 (Jackson cross-cylinder, axes at 180 degrees and 90 degrees) in x-axis versus J45 (Jackson cross-cylinder, axes at 45 degrees and 135 degrees) in y-axis.
Figure 2. Postoperative plot of J0 (Jackson cross-cylinder, axes at 180 degrees and 90 degrees) in x-axis versus J45 (Jackson cross-cylinder, axes at 45 degrees and 135 degrees) in y-axis.
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Table 3. Characteristics and preoperative values of the patients who had an additional enhancement. Patient 1 2 3 4 5 6 7 8 9 10
Eye
Age (Y)
Refraction
SE (D)
K1 (D) 3 Axis ( )
K2 (D) 3 Axis ( )
Right Right Left Right Left Right Left Left Right Left
40 60 53 60 53 55 48 47 68 46
C0.25 0.75 88 0.00 0.50 98 C0.75 0.75 111 C0.25 1.25 110 C0.75 1.00 122 C1.00 0.75 107 0.00 1.25 29 C1.00 0.75 26 0.00 0.50 98 C0.50 1.00 175
0.125 0.25 C0.375 0.375 C0.25 C0.625 0.625 C0.625 0.25 0.00
44.8 138.9 42.2 176.1 41.9 102.9 43.5 114.6 41.4 163.5 41.4 139.7 41.1 12.7 40.1 27.4 43.6 108.5 42.2 6.4
46.0 48.9 43.2 86.1 42.5 12.9 44.0 24.6 44.1 73.5 42.0 49.7 42.0 102.7 41.2 117.4 43.8 18.5 43.0 96.4
K1 Z flat keratometry; K2 Z steep keratometry; SE Z spherical equivalent
In 2008, Bahar et al.4 compared 20 manually performed astigmatic keratotomies (AKs) and 20 Intralase femtosecond-assisted AKs after keratoplasty. The UDVA and CDVA were significantly increased in the Intralase group but not in the manual AK group. In the manual AK group, 3 perforations that had to be sutured occurred. This is in accordance with our study in which we could show that arcuate incisions lead to a significant reduction in astigmatism and improvement of visual acuity in cases of residual astigmatism after implantation of trifocal IOLs. No perforations occurred, thus the automated surgery is safe, predictable, and precise. To our knowledge, this is the first study with a sizeable number of patients receiving secondary epitheliumpenetrating femtosecond laser–assisted arcuate incisions for correction of residual astigmatism after RLE with trifocal IOLs. In the present study, the astigmatic correction was based on the refractive astigmatic error alone, which does not necessarily coincide with the keratometric astigmatism. That might be the success of correction and could explain the advantage of a secondary pseudophakic surgery. In our study, the depth of the penetrating femtosecond laser–assisted arcuate incisions was set at 80% of the corneal thickness with a 90-degree side-cut angle. Our correction was based on a modified Woodcock nomogram,B which must be adapted to this application in the future. The OZ diameter was kept to a constant size
of 8.0 mm diameter. The only adjusted parameters in our setting were the length and the number of applied incisions (1 or 2). According to L€offler et al.,13 this means that in eyes with a larger corneal diameter, the incisions were placed more central in relation to the size of the cornea compared with eyes with a smaller corneal diameter. This might lead to higher astigmatic correction in eyes with a larger corneal diameter. L€offler et al.13 also gave attention to the biomechanical effect of penetrating femtosecond-assisted keratotomy to the cornea and found a significant reduction of the anterior corneal astigmatism and the total corneal refractive power but no influence on the posterior corneal astigmatism. Understanding these effects might lead to optimized nomograms and more predictable results. Other issues are whether penetrating or nonpenetrating incisions are safer and more effective, and for which technique there is a higher grade of induction of higher-order aberrations (HOAs). The arcuate incisions in the present study were epithelium-penetrating and manually opened to gain an adequate refractive effect. R€ uckl et al.14 also demonstrated that intrastromal arcuate incisions have a significant effect. They treated naturally occurring astigmatism or residual astigmatism after cataract surgery. After 6 months, the mean refractive cylinder decreased to 0.33 G 0.42 D from initially 1.41 G 0.66 D. Advantages were seen in the nonperforation of Bowman membrane as a stabilizing layer in
Table 4. Postoperative values of the patients who had an additional enhancement. Patient 1 2 3 4 5 6 7 8 9 10
Refraction
SE (D)
Enhancement
0.00 1.00 110 0.50 0.00 0 C0.75 0.25 70 C0.25 1.00 102 C0.25 0.50 118 C0.75 0.50 92 0.25 0.75 20 C1.00 0.50 24 0.75 0.00 0 C0.75 1.00 112
0.50 0.50 C0.625 0.25 0.00 C0.50 0.625 C0.75 0.75 C0.25
Femto-LASIK Femto-LASIK Femto-LASIK Second arcuate incision Femto-LASIK Second arcuate incision PRK Second arcuate incision Femto-LASIK Second arcuate incision
Femto-LASIK Z femtosecond laser–assisted laser in situ keratomileusis; PRK Z photorefractive keratectomy; SE Z spherical equivalent
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the cornea and in an intact epithelium. Venter et al.8 reported on the correction of mixed astigmatism after previous refractive surgery with intrastromal femtosecondassisted AK. To our knowledge, no study exists in which the refractive outcomes after intrastromal or epithelialpenetrating arcuate incisions were compared directly. Chan et al.9 analyzed the corneal astigmatism and development of HOAs after penetrating arcuate incisions performed during femtosecond laser–assisted cataract surgery. The corneal astigmatism was significantly reduced, the HOAs increased significantly except for the spherical aberrations. No difference in outcomes was seen between 2 months and 2 years, indicating a stable situation. Concerning the question of regression of the corrective effect, the values after 1 week and after the mean follow-up of 6 G 5 months were compared. There was no statistically significant difference. Finally, possible side-effects of different procedures must be noted. The unplanned enhancement after lens surgery is frequently performed with PRK or femtosecond-assisted LASIK. These 2 ablation procedures have similar reliability for correction in pseudophakic patients15,16 and provide excellent predictability and safety profiles. In addition, they can correct associated spherical deviations from the target. However, LASIK could have disadvantages such as stromal wrinkles, flap displacement, diffuse lamellar keratitis,17–19 and dry-eye syndrome.20 Dry-eye syndrome is a common condition in elderly patients who in general represent the patient group for RLEs. Although the performance of LASIK enhancement in pseudophakic patients is very good (92% within G 0.5 D),21 postoperative dry-eye syndrome could be responsible for delayed healing and visual fluctuation. Arcuate incisions after RLE might be a good alternative in patients with dry-eye syndrome and mixed astigmatism. In our study, we did not specifically evaluate this aspect; however, no spontaneous patient reports about an increase in dry-eye symptoms occurred. Patients in the present study reported a light discomfort for the first few postoperative days and gained a fast visual and functional rehabilitation despite penetrating incisions. Residual astigmatism was significantly reduced and UDVA increased significantly. In this study, 10.53% of the patients required a further enhancement with either a second surgery with arcuate incisions or femtosecond-assisted LASIK or PRK. All the patients were unsatisfied with the postoperative refractive results. One patient had additional glare and was therefore treated with femtosecond-assisted LASIK. Limitations of this study include its retrospective nature and the manifest subjective refraction as the deciding parameter. On the other hand, the latter is what is clinically important and realistically reproducible. In summary, this study is a retrospective first description of arcuate incisions correcting low residual refractive astigmatism after trifocal IOL implantation. Safety with 1.0 and efficacy with 0.89 were very good and relevant complications did not occur. Further studies are required to develop a new, valid, and more predictable nomogram for femtosecond-assisted keratotomy as an enhancement Volume - Issue - - 2018
procedure to reduce refractive astigmatism after multifocal IOL implantation.
WHAT WAS KNOWN Remaining corneal astigmatism, especially after keratoplasty, is regularly reduced by femtosecond–laser assisted corneal arcuate incisions. Intrastromal femtosecond–laser assisted arcuate incisions can reduce mixed astigmatism in patients after previous refractive surgery.
WHAT THIS PAPER ADDS Femtosecond laser–assisted epithelium-penetrating arcuate incisions were precise, safe, efficient, and feasible to reduce refractive astigmatism after trifocal IOL implantation.
REFERENCES 1. Kook D, Buhren J, Klaproth OK, Bauch AS, Derhartunian V, Kohnen T. Astigmatische Keratotomie mit dem Femtosekundenlaser [Astigmatic keratotomy with the femtosecond laser: correction of high astigmatisms after keratoplasty]. Ophthalmologe 2011; 108:143–150 2. Nubile M, Carpineto P, Lanzini M, Calienno R, Agnifili L, Ciancaglini M, Mastropasqua L. Femtosecond laser arcuate keratotomy for the correction of high astigmatism after keratoplasty. Ophthalmology 2009; 116:1083– 1092 3. Kumar NL, Kaiserman I, Shehadeh-Mashor R, Sansanayudh W, Ritenour R, Rootman DS. IntraLase-enabled astigmatic keratotomy for post-keratoplasty astigmatism: on-axis vector analysis. Ophthalmology 2010; 117:1228–1235 4. Bahar I, Levinger E, Kaiserman I, Sansanayudh W, Rootman DS. IntraLaseenabled astigmatic keratotomy for postkeratoplasty astigmatism. Am J Ophthalmol 2008; 146:897–904 5. Wu E. Femtosecond-assisted astigmatic keratotomy. Int Ophthalmol Clin 2011; 51:77–85 s6. Mendicute J, Irigoyen C, Ruiz M, Illarramendi I, Ferrer-Blasco T, Monte R. Toric intraocular lens versus opposite clear corneal incisions to corMico rect astigmatism in eyes having cataract surgery. J Cataract Refract Surg 2009; 35:451–458 7. Yoo A, Yun S, Kim JY, Kim MJ, Tchah H. Femtosecond laser-assisted arcuate keratotomy versus toric iol implantation for correcting astigmatism. J Refract Surg 2015; 31:574–578 8. Venter J, Blumenfeld R, Schallhorn S, Pelouskova M. Non-penetrating femtosecond laser intrastromal astigmatic keratotomy in patients with mixed astigmatism after previous refractive surgery. J Refract Surg 2013; 29:180–186 9. Chan TC, Ng AL, Cheng GP, Wang Z, Woo VC, Jhanji V. Corneal astigmatism and aberrations after combined femtosecond-assisted phacoemulsification and arcuate keratotomy: two-year results. Am J Ophthalmol 2016; 170:83–90 10. Nejima R, Terada Y, Mori Y, Ogata M, Minami K, Miyata K. Clinical utility of femtosecond laser-assisted astigmatic keratotomy after cataract surgery. Jpn J Ophthalmol 2015; 59:209–215 11. Thibos LN, Horner D. Power vector analysis of the optical outcome of refractive surgery. J Cataract Refract Surg 2001; 27:80–85 12. Duffey RJ, Jain VN, Tchah H, Hofmann RF, Lindstrom RL. Paired arcuate keratotomy. A surgical approach to mixed and myopic astigmatism. Arch Ophthalmol 1988; 106:1130–1135 €ffler F, Bohm M, Herzog M, Petermann K, Kohnen T. Tomographic 13. Lo analysis of anterior and posterior and total corneal refractive power changes after femtosecond laser-assisted keratotomy. Am J Ophthalmol 2017; 180:102–109 €ckl T, Dexl AK, Bachernegg A, Reischl V, Riha W, Ruckhofer J, 14. Ru Binder PS, Grabner G. Femtosecond laser-assisted intrastromal arcuate keratotomy to reduce corneal astigmatism. J Cataract Refract Surg 2013; 39:528–538 15. Sanchez-Galeana CA, Smith RJ, Rodriguez X, Montes M, Chayet AS. Laser in situ keratomileusis and photorefractive keratectomy for residual refractive error after phakic intraocular lens implantation. J Refract Surg 2001; 17:299–304
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16. Macsai MS, Fontes BM. Refractive enhancement following presbyopiacorrecting intraocular lens implantation. Curr Opin Ophthalmol 2008; 19:18–21 17. Norouzi H, Rahmati-Kamel M. Laser in situ keratomileusis for correction of induced astigmatism from cataract surgery. J Refract Surg 2003; 19:416–424 18. Sutton G, Lawless M, Hodge C. Laser in situ keratomileusis in 2012: a review. Clin Exp Optom 2014; 97:18–29 19. Iskander NG, Peters NT, Penno EA, Gimbel HV. Postoperative complications in laser in situ keratomileusis. Curr Opin Ophthalmol 2000; 11:273–279 20. Benitez-del-Castillo JM, del Rio T, Iradier T, Hernandez JL, Castillo A, Garcia-Sanchez J. Decrease in tear secretion and corneal sensitivity after laser in situ keratomileusis. Cornea 2001; 20:30–32 ndez-Buenaga R, Alio JL, Pe rez Ardoy AL, Quesada AL, Pinilla-Corte s L, 21. Ferna Barraquer RI. Resolving refractive error after cataract surgery: IOL exchange, piggyback lens, or LASIK. J Refract Surg 2013; 29:676–683
B. Talamo JH, Hatch KM, Woodcock EC. Nomogram Development for Femtosecond Laser Arcuate Incisions in Refractive Laser-Assisted Cataract Surgery. ASCRS Paper Session 4-B: Intraocular Surgery. Boston Convention and Exhibition Center 2014
Disclosures: None of the authors has a financial or proprietary interest in any material or method mentioned.
First author: €deke, MD Inger Lu EuroEyes Clinical Group, Hamburg, Germany
OTHER CITED MATERIAL A. Donnenfeld ED. Correcting Corneal Astigmatism With Laser Incisions. Cataract and Refractive Surgery Today, 2014; 30–31
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ARTICLE
Refractive outcomes of femtosecond laser–assisted secondary arcuate incisions in patients with residual refractive astigmatism after trifocal intraocular lens implantations Inger L€ udeke, MD, Johannes Gonnermann, MD, Jørn Jørgensen, MD, Thomas Neuhann, MD, Keith McKay, BSc Optom, Mathias Fleischer, MD, Peter Galambos, MD, Ralf-Christian Lerche, MD
Purpose: To evaluate the refractive and visual outcomes of arcuate incisions performed with the femtosecond laser in patients with a residual refractive astigmatism after refractive lens exchange (RLE) with trifocal intraocular lenses (IOLs). Setting: EuroEyes Clinical Group, Hamburg, Germany. Design: Retrospective interventional case series. Methods: Pseudophakic patients with remaining refractive astigmatism after RLE with a trifocal IOL were treated with femtosecond laser–assisted corneal arcuate incisions. Patients who had a previous corneal treatment were excluded. Outcome measures were uncorrected (UDVA) and corrected distance visual acuities, manifest refraction, and a power vector analysis.
Results: The study enrolled 95 eyes of 70 patients. The mean follow-up was 5.6 months G 4.9 (SD). Constructing an
P
atient satisfaction with multifocal intraocular lenses (IOLs) is highly dependent on a precise emmetropic refraction outcome. This requires the correction of preexisting astigmatism, either with toric IOLs or with lower astigmatism, by carefully choosing the incision site in the steep axis. Despite good surgical planning and performance, residual astigmatism might occur. Astigmatisms greater than 0.50 diopter (D) could result in unsatisfactory outcomes.A There are different methods for correcting preexisting and/or residual astigmatism after cataract surgery. Manually performed arcuate incisions or limbal relaxing
astigmatic power vector (APV) with Jackson cross-cylinder axes at 180 degrees and 90 degrees and Jackson crosscylinder axes at 45 degrees and 135 degrees, the mean preoperative vector length was 0.46 G 0.16 diopter (D). The mean postoperative APV was 0.17 G 0.16 D. This difference was statistically significant (P < .001). The difference between the UDVA preoperatively (0.17 G 0.15) and postoperatively (0.08 G 0.10) was statistically significant (P < .001). No intraoperative or postoperative complications were observed.
Conclusion: Femtosecond laser–assisted corneal arcuate incisions were safe, efficient, and feasible to reduce refractive astigmatism after trifocal IOL implantation. J Cataract Refract Surg 2018; -:-–- Q 2018 ASCRS and ESCRS Published by Elsevier Inc
incisions1–5 as well as the classic ablative procedures such as photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) are widely performed.1–4 Disadvantages of manually performed arcuate incisions are low predictability and the risk for perforation.3–5 Laser in situ keratomileusis enhancements result in good refractive results but can lead to neurotrophic problems and dry-eye syndrome with decreased visual acuity, especially in older patients.1–5 With the introduction of the femtosecond laser into corneal and cataract surgeries, new possibilities have arisen for the precision of incisional correction of astigmatism.
Submitted: September 13, 2017 | Final revision submitted: August 6, 2018 | Accepted: August 9, 2018 Universit€atsmedizin Berlin €deke, Gonnermann, Jørgensen, Neuhann, McKay, Fleischer, Galambos, Lerche), Hamburg, Charite From the EuroEyes Clinical Group (Lu (Gonnermann), Department of Ophthalmology, Berlin, MVZ Prof. Neuhann (Neuhann), Munich, and Universit€atsklinikum Hamburg-Eppendorf (Lerche), Department of Ophthalmology, Hamburg, Germany. €deke and Gonnermann contributed equally to this work. Drs. Lu €deke, MD, EuroEyes Clinical Group, Ophthalmology, Valentinskamp 90, Hamburg 20355, Germany. Email: [email protected]. Corresponding author: Inger Lu Q 2018 ASCRS and ESCRS Published by Elsevier Inc.
0886-3350/$ - see frontmatter https://doi.org/10.1016/j.jcrs.2018.08.024
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Nowadays, corneal arcuate incisions are regularly performed with the femtosecond laser, and they are commonly used to reduce corneal astigmatism during femtosecond laser–assisted cataract surgery,6 but also as a standalone procedure in patients with remaining astigmatism after keratoplasty or cataract surgery.7–10 Advantages of femtosecond laser–assisted arcuate incisions are higher accuracy and reproducibility of the length, the depth, the inclination, and the optical zone (OZ) diameter of the arcuate incisions as well as the unique possibility of offering the option to not penetrate the outer surface of the cornea but performing them wholly intrastromally.1–4 In this study, we evaluated the refractive outcomes of epithelium-penetrating femtosecond laser–assisted arcuate keratotomy in patients with residual refractive astigmatism after the implantation of trifocal IOLs as an alternative to other refractive secondary surgeries such as touch-up LASIK or add-on IOLs. PATIENTS AND METHODS Study Design This study is a retrospective analysis of all consecutive patients who had femtosecond laser–assisted keratotomy after implantation of a trifocal IOL (AT LISA tri 839MP or AT LISA tri toric 939MP, both Carl Zeiss Meditec AG) in the EuroEyes Clinical Group in Hamburg, Germany, from January 1, 2014 to October 31, 2015. The study was conducted in accordance with the tenets of the Declaration of Helsinki. All patients signed a written informed consent form before the surgery. Inclusion criteria were a spherical equivalent (SE) within G0.5 D and an astigmatism by subjective refraction greater than or equal to 0.5 D. Eyes that had a corneal refractive treatment before the implantation of an artificial lens, eyes that had a refractive enhancement before the arcuate incision, and eyes with an irregular corneal astigmatism were excluded. All patients underwent a preoperative ophthalmic examination including uncorrected (UDVA) and corrected (CDVA) distance visual acuities, autorefraction, slitlamp biomicroscopy, dilated fundoscopy, and high-resolution rotating Scheimpflug imaging (Pentacam HR, Oculus Optikger€ate GmbH) with keratometry, topography, and pachymetry. Postoperative examinations, which included UDVA and CDVA, autorefraction, and slitlamp biomicroscopy, were scheduled for the first day, then 1 week, 1 month, and 3 months later. Surgical Technique The arcuate incisions were performed by one of two experienced surgeons (J.J. and R.C.L.) between January 1, 2014 and October 31, 2015. All procedures were performed under topical anesthesia with a femtosecond laser (Lensx, Alcon Laboratories, Inc.). The astigmatic treatment was based alone on the subjective refraction. Keratometric (K) values were collected but had no impact on the calculation of the incision parameters made with the treatment nomogram (Table 1). The arcuate incisions were performed using the following settings. A paired reference point at the temporal limbus (0- to 180-degree) was marked using a pendular marker (Gerten Corneal Pendulum Marker, Geuder AG) while the patient was in an upright position. The depth of the incision was set at 80% of the corneal thickness with a 90-degree side-cut angle. The OZ diameter was aimed at 8.0 mm. The incisions were created with a programmed energy setting of 3.0 mJ and a spot/line separation of 4 4 mm. After the laser surgery, the incisions were opened manually. Postoperatively, antibiotics (Floxal edo eyedrops 3 mg/ml, 4 times a day) and lubrication eyedrops were prescribed for 1 week. Volume - Issue - - 2018
Table 1. Study authors’ nomogram (modified from a Woodcock nomogramB). K Value (D)
Incision, Number ( )
%0.75 %1.00 %1.25 %1.50 %2.0 %2.5
1 (45) 2 (44 each) 2 (44 and 45) 2 (45 each) 2 (47 each) 2 (49 each)
K Z keratometry
The SPSS Statistics for Windows software package (version 21.0, IBM Corp.) was used for statistical analysis. The Kolmogorov-Smirnov test was used to check the normality of the data distribution. When parametric analysis was possible, the paired Student t test was performed for all parameter comparisons between preoperative and postoperative examinations as well as between consecutive postoperative visits. Otherwise, when parametric analysis was not possible, the Wilcoxon rank-sum test was applied to assess the significance of differences between consecutive examinations. In all cases, a P value less than 0.05 was considered statistically significant. Vector Analysis The astigmatic value was described using the power vector analysis: If the spherical power is removed, the result is a Jackson crossed-cylinder with axes at 90 degrees and 180 degrees (J0), and a Jackson crossed-cylinder with axis at 45 and 135 degrees (J45). The following formulas for calculating the vector lengths were used: J0 Z ðC=2Þcosð2aÞ; and J45 Z ðC=2Þsinð2aÞ with C for the cylindric value with C O 0 for C cyl and C ! 0 for cyl form. Astigmatic power vector ðAPVÞ Z root ðJ02 þ J452 Þ and B Z root ðM2 þ J02 þ J452 Þ with B indicating the overall blurring strength including the spherical and cylindric values and M indicating the power of a lens that is equal to the SE.11
RESULTS The study analyzed 95 eyes of 70 patients (43 women, 27 men). The mean age was 55 years G 8 (SD). The level of refractive astigmatism ranged from 0.5 to 2.25 D. The mean K values were 42.67 G 1.97 D in the flat axis and 43.71 G 2.09 D in the steep axis. The primary corneal astigmatism before refractive lens exchange (RLE) ranged from 0 to 6.4 D. Fifty-nine eyes (62.1% had astigmatism of 1.0 D or less, 28 eyes (29.5%) had astigmatism between greater than 1.0 D and 2 D or less, 5 eyes (5.2%) were between greater than 2.0 D and 3 D or less, and 3 eyes (3.2%) had astigmatism greater than 3.0 D. The mean corneal astigmatism was 1.05 G 0.94 D. The femtosecond-assisted keratotomy was performed 3 months after the initial RLE at the earliest (mean 7.0 G 3.4 months; range 3 to 37 months). Table 2 shows the preoperative characteristics of the patient population. Preoperatively, the mean SE was 0.07 G 0.38 D, the vector J0 was 0.24 G 0.33 D, and
REFRACTIVE OUTCOMES OF FEMTOSECOND-LASER ARCUATE INCISIONS
Table 2. Patient characteristics preoperatively. Parameter Sex Male Female Eyes Right Left IOL type Spheric Toric Astigmatism (D) 0.5 0.75 1.0 1.25–1.50 1.75–2.25
Number of Eyes (%) 51 (53.6) 44 (46.4) 46 (48.4) 49 (51.6) 63 32
(66) (34)
13 (13.7) 34 (35.8) 28 (29.5) 18 (18.9) 2 (2.1)
IOL Z intraocular lens
the vector J45 was 0.03 G 0.28 D. Constructing an APV with J0 and J45, the mean preoperative vector length was 0.46 G 0.16 D. The mean overall blurring strength B was 0.58 G 0.23 D. Figure 1 shows the preoperative refractive astigmatic components (J0 and J45). After a mean follow-up of 6 G 5 months, the mean postoperative SE was 0.05 G 0.35 D. The difference between the preoperative and postoperative values was not statistically significant (P Z .553). The mean postoperative vector J0 was 0.06 G 0.17 D. The difference between the preoperative and postoperative values was statistically significant (P ! .001). The mean postoperative vector J45 was 0.00 G 0.15 D. The difference between the preoperative and postoperative values was not statistically significant (P Z .290). The mean postoperative astigmatic power vector was 0.17 G 0.16 D. The difference between the preoperative and postoperative astigmatic power vectors was statistically significant (P ! .001). The mean postoperative overall blurring strength B was 0.35 G 0.23 D. The difference between the preoperative and postoperative values was statistically significant (P ! .001). To investigate the stability of the refraction during the follow-up period, the results after 1 week and at the last follow-up (6 G 5 months) were evaluated. The SE after 1 week was 0.05 G 0.33 D and showed no statistically significant difference from the last follow-up visit (P Z .738). The vector J0 (0.04 G 0.18 D) and vector J45 (0.02 G 0.13 D) after 1 week were not significantly different from the postoperative values after 6 months (P Z .217 and P Z .300, respectively). Finally, the astigmatic power vector was 0.15 G 0.16 after 1 week and remained stable over the follow-up period (P Z .327). Figure 2 shows the postoperative values. The postoperative values are closer to the origin than the preoperative values, which show a more scattered picture.
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The CDVA in logarithm of the minimum angle of resolution (logMAR) was 0.02 G 0.05 preoperatively compared with 0.03 G 0.07 postoperatively (P Z .759). The UDVA in logMAR improved significantly from 0.17 G 0.15 preoperatively to 0.08 G 0.10 postoperatively (P ! .001). The mean safety index (CDVA preoperatively/ CDVA postoperatively) was calculated with 1.0 and the mean efficacy index (UDVA postoperatively/CDVA preoperatively) with 0.89. Table 2 shows the preoperative astigmatism of the study eyes. Postoperatively, 51 eyes (53.7%) had a residual astigmatism of 0 to 0.25 D, 28 eyes (29.5%) had 0.5 D left. Overall, 79 eyes (83.2%) were within G0.5 D astigmatism postoperatively. Two eyes were overcorrected with a refractive astigmatism of 0.5 D or more in an axis between 60 and 120 degrees away from the original axis. The first eye’s refractive value was 0.75 1.0 102 preoperatively and resulted in 0.25 0.50 38 postoperatively. The second eye’s refractive value was 0.5 1.0 175 before surgery and 0.75 1.0 112 postoperatively. Fifty-two (74.7 %) of the 70 patients were satisfied with the postoperative result. Ten (10.5%) of the 95 eyes received an additional enhancement either with LASIK (5 eyes), PRK (1 eye), or a further femtosecond laser–assisted arcuate incision (4 eyes) (Tables 3 and 4). No intraoperative or postoperative events, such as perforation or infection, were observed. DISCUSSION The purpose of this retrospective study was to evaluate the refractive and visual outcomes after epithelium-penetrating femtosecond laser–assisted arcuate incisions in patients with remaining astigmatism after implantation of a trifocal IOL. The demand for a precise emmetropic outcome is especially high after implantation of multifocal lenses. From the literature, we know that postoperative astigmatism is an important issue for the outcome of lens surgery. A postoperative residual astigmatism greater than 0.50 D can lead to blurry vision and therefore to patient dissatisfaction.A Compared with higher grades of astigmatism, relaxing incisions seem to be a helpful tool in lower post-surgical astigmatism. After performing experimental cadaver trials, Duffey et al.12 concluded that arcuate incisions are ideal for mixed astigmatism. In the steep axis, the cornea experiences a myopic shift, whereas the flat axis becomes steeper to a lower degree. This is known as the coupling effect. In the present study, arcuate incisions were primarily used in patients with a mixed astigmatism. The mean preoperative SE was 0.07 G 0.38 D. The mean postoperative SE was 0.05 G 0.35 D. The stability of the SE reflects the coupling effect and seems to be also suitable for arcuate incisions based on the refraction alone. With this refractive preselection, good refractive and visual results are obtained with arcuate incisions created with the femtosecond laser in patients with multifocal IOLs. Volume - Issue - - 2018
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Figure 1. Preoperative plot of J0 (Jackson cross-cylinder, axes at 180 degrees and 90 degrees) in x-axis versus J45 (Jackson cross-cylinder, axes at 45 degrees and 135 degrees) in y-axis.
Figure 2. Postoperative plot of J0 (Jackson cross-cylinder, axes at 180 degrees and 90 degrees) in x-axis versus J45 (Jackson cross-cylinder, axes at 45 degrees and 135 degrees) in y-axis.
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Table 3. Characteristics and preoperative values of the patients who had an additional enhancement. Patient 1 2 3 4 5 6 7 8 9 10
Eye
Age (Y)
Refraction
SE (D)
K1 (D) 3 Axis ( )
K2 (D) 3 Axis ( )
Right Right Left Right Left Right Left Left Right Left
40 60 53 60 53 55 48 47 68 46
C0.25 0.75 88 0.00 0.50 98 C0.75 0.75 111 C0.25 1.25 110 C0.75 1.00 122 C1.00 0.75 107 0.00 1.25 29 C1.00 0.75 26 0.00 0.50 98 C0.50 1.00 175
0.125 0.25 C0.375 0.375 C0.25 C0.625 0.625 C0.625 0.25 0.00
44.8 138.9 42.2 176.1 41.9 102.9 43.5 114.6 41.4 163.5 41.4 139.7 41.1 12.7 40.1 27.4 43.6 108.5 42.2 6.4
46.0 48.9 43.2 86.1 42.5 12.9 44.0 24.6 44.1 73.5 42.0 49.7 42.0 102.7 41.2 117.4 43.8 18.5 43.0 96.4
K1 Z flat keratometry; K2 Z steep keratometry; SE Z spherical equivalent
In 2008, Bahar et al.4 compared 20 manually performed astigmatic keratotomies (AKs) and 20 Intralase femtosecond-assisted AKs after keratoplasty. The UDVA and CDVA were significantly increased in the Intralase group but not in the manual AK group. In the manual AK group, 3 perforations that had to be sutured occurred. This is in accordance with our study in which we could show that arcuate incisions lead to a significant reduction in astigmatism and improvement of visual acuity in cases of residual astigmatism after implantation of trifocal IOLs. No perforations occurred, thus the automated surgery is safe, predictable, and precise. To our knowledge, this is the first study with a sizeable number of patients receiving secondary epitheliumpenetrating femtosecond laser–assisted arcuate incisions for correction of residual astigmatism after RLE with trifocal IOLs. In the present study, the astigmatic correction was based on the refractive astigmatic error alone, which does not necessarily coincide with the keratometric astigmatism. That might be the success of correction and could explain the advantage of a secondary pseudophakic surgery. In our study, the depth of the penetrating femtosecond laser–assisted arcuate incisions was set at 80% of the corneal thickness with a 90-degree side-cut angle. Our correction was based on a modified Woodcock nomogram,B which must be adapted to this application in the future. The OZ diameter was kept to a constant size
of 8.0 mm diameter. The only adjusted parameters in our setting were the length and the number of applied incisions (1 or 2). According to L€offler et al.,13 this means that in eyes with a larger corneal diameter, the incisions were placed more central in relation to the size of the cornea compared with eyes with a smaller corneal diameter. This might lead to higher astigmatic correction in eyes with a larger corneal diameter. L€offler et al.13 also gave attention to the biomechanical effect of penetrating femtosecond-assisted keratotomy to the cornea and found a significant reduction of the anterior corneal astigmatism and the total corneal refractive power but no influence on the posterior corneal astigmatism. Understanding these effects might lead to optimized nomograms and more predictable results. Other issues are whether penetrating or nonpenetrating incisions are safer and more effective, and for which technique there is a higher grade of induction of higher-order aberrations (HOAs). The arcuate incisions in the present study were epithelium-penetrating and manually opened to gain an adequate refractive effect. R€ uckl et al.14 also demonstrated that intrastromal arcuate incisions have a significant effect. They treated naturally occurring astigmatism or residual astigmatism after cataract surgery. After 6 months, the mean refractive cylinder decreased to 0.33 G 0.42 D from initially 1.41 G 0.66 D. Advantages were seen in the nonperforation of Bowman membrane as a stabilizing layer in
Table 4. Postoperative values of the patients who had an additional enhancement. Patient 1 2 3 4 5 6 7 8 9 10
Refraction
SE (D)
Enhancement
0.00 1.00 110 0.50 0.00 0 C0.75 0.25 70 C0.25 1.00 102 C0.25 0.50 118 C0.75 0.50 92 0.25 0.75 20 C1.00 0.50 24 0.75 0.00 0 C0.75 1.00 112
0.50 0.50 C0.625 0.25 0.00 C0.50 0.625 C0.75 0.75 C0.25
Femto-LASIK Femto-LASIK Femto-LASIK Second arcuate incision Femto-LASIK Second arcuate incision PRK Second arcuate incision Femto-LASIK Second arcuate incision
Femto-LASIK Z femtosecond laser–assisted laser in situ keratomileusis; PRK Z photorefractive keratectomy; SE Z spherical equivalent
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the cornea and in an intact epithelium. Venter et al.8 reported on the correction of mixed astigmatism after previous refractive surgery with intrastromal femtosecondassisted AK. To our knowledge, no study exists in which the refractive outcomes after intrastromal or epithelialpenetrating arcuate incisions were compared directly. Chan et al.9 analyzed the corneal astigmatism and development of HOAs after penetrating arcuate incisions performed during femtosecond laser–assisted cataract surgery. The corneal astigmatism was significantly reduced, the HOAs increased significantly except for the spherical aberrations. No difference in outcomes was seen between 2 months and 2 years, indicating a stable situation. Concerning the question of regression of the corrective effect, the values after 1 week and after the mean follow-up of 6 G 5 months were compared. There was no statistically significant difference. Finally, possible side-effects of different procedures must be noted. The unplanned enhancement after lens surgery is frequently performed with PRK or femtosecond-assisted LASIK. These 2 ablation procedures have similar reliability for correction in pseudophakic patients15,16 and provide excellent predictability and safety profiles. In addition, they can correct associated spherical deviations from the target. However, LASIK could have disadvantages such as stromal wrinkles, flap displacement, diffuse lamellar keratitis,17–19 and dry-eye syndrome.20 Dry-eye syndrome is a common condition in elderly patients who in general represent the patient group for RLEs. Although the performance of LASIK enhancement in pseudophakic patients is very good (92% within G 0.5 D),21 postoperative dry-eye syndrome could be responsible for delayed healing and visual fluctuation. Arcuate incisions after RLE might be a good alternative in patients with dry-eye syndrome and mixed astigmatism. In our study, we did not specifically evaluate this aspect; however, no spontaneous patient reports about an increase in dry-eye symptoms occurred. Patients in the present study reported a light discomfort for the first few postoperative days and gained a fast visual and functional rehabilitation despite penetrating incisions. Residual astigmatism was significantly reduced and UDVA increased significantly. In this study, 10.53% of the patients required a further enhancement with either a second surgery with arcuate incisions or femtosecond-assisted LASIK or PRK. All the patients were unsatisfied with the postoperative refractive results. One patient had additional glare and was therefore treated with femtosecond-assisted LASIK. Limitations of this study include its retrospective nature and the manifest subjective refraction as the deciding parameter. On the other hand, the latter is what is clinically important and realistically reproducible. In summary, this study is a retrospective first description of arcuate incisions correcting low residual refractive astigmatism after trifocal IOL implantation. Safety with 1.0 and efficacy with 0.89 were very good and relevant complications did not occur. Further studies are required to develop a new, valid, and more predictable nomogram for femtosecond-assisted keratotomy as an enhancement Volume - Issue - - 2018
procedure to reduce refractive astigmatism after multifocal IOL implantation.
WHAT WAS KNOWN Remaining corneal astigmatism, especially after keratoplasty, is regularly reduced by femtosecond–laser assisted corneal arcuate incisions. Intrastromal femtosecond–laser assisted arcuate incisions can reduce mixed astigmatism in patients after previous refractive surgery.
WHAT THIS PAPER ADDS Femtosecond laser–assisted epithelium-penetrating arcuate incisions were precise, safe, efficient, and feasible to reduce refractive astigmatism after trifocal IOL implantation.
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16. Macsai MS, Fontes BM. Refractive enhancement following presbyopiacorrecting intraocular lens implantation. Curr Opin Ophthalmol 2008; 19:18–21 17. Norouzi H, Rahmati-Kamel M. Laser in situ keratomileusis for correction of induced astigmatism from cataract surgery. J Refract Surg 2003; 19:416–424 18. Sutton G, Lawless M, Hodge C. Laser in situ keratomileusis in 2012: a review. Clin Exp Optom 2014; 97:18–29 19. Iskander NG, Peters NT, Penno EA, Gimbel HV. Postoperative complications in laser in situ keratomileusis. Curr Opin Ophthalmol 2000; 11:273–279 20. Benitez-del-Castillo JM, del Rio T, Iradier T, Hernandez JL, Castillo A, Garcia-Sanchez J. Decrease in tear secretion and corneal sensitivity after laser in situ keratomileusis. Cornea 2001; 20:30–32 ndez-Buenaga R, Alio JL, Pe rez Ardoy AL, Quesada AL, Pinilla-Corte s L, 21. Ferna Barraquer RI. Resolving refractive error after cataract surgery: IOL exchange, piggyback lens, or LASIK. J Refract Surg 2013; 29:676–683
B. Talamo JH, Hatch KM, Woodcock EC. Nomogram Development for Femtosecond Laser Arcuate Incisions in Refractive Laser-Assisted Cataract Surgery. ASCRS Paper Session 4-B: Intraocular Surgery. Boston Convention and Exhibition Center 2014
Disclosures: None of the authors has a financial or proprietary interest in any material or method mentioned.
First author: €deke, MD Inger Lu EuroEyes Clinical Group, Hamburg, Germany
OTHER CITED MATERIAL A. Donnenfeld ED. Correcting Corneal Astigmatism With Laser Incisions. Cataract and Refractive Surgery Today, 2014; 30–31
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