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PubMed2000

Fourier analysis of irregular astigmatism after implantation of 3 types of intraocular lenses.

PURPOSE: To evaluate irregular astigmatism after silicone, acrylic, and poly(methyl methacrylate) (PMMA) intraocular lens (IOL) implantation using Fourier analysis of videokeratography data. METHODS: Two hundred forty eyes having phacoemulsification and IOL implantation were randomly assigned to 1 of 3 groups: 3.5 mm incision and silicone IOL, 4.1 mm incision and acrylic IOL, or 6.5 mm incision and PMMA IOL. All eyes had videokeratographic examinations preoperatively and 2, 4, and 10 days and 1 and 3 months postoperatively. The dioptric data of the central cornea were decomposed into spherical equivalent, regular astigmatism, and irregular astigmatism (decentration and higher-order irregularity) components using Fourier analysis. RESULTS: Regular astigmatism in the PMMA group was greater than in the silicone and acrylic groups. Decentration in all 3 groups increased significantly postoperatively but virtually returned to preoperative levels by 10 days. No significant difference was observed among the 3 groups. Higher-order irregularity significantly increased after surgery in all 3 groups. The higher-order irregularity in the PMMA group persisted for up to 1 month, while that in the silicone and acrylic groups returned to preoperative levels by 4 days, resulting in significant differences between these groups 10 days and 1 month after IOL implantation. CONCLUSION: Irregular astigmatism, both the decentration and higher-order irregularity components, increased significantly after 3 types of scleral tunnel incisions for silicone, acrylic, or PMMA IOL implantation but returned to preoperative levels soon after surgery except for the higher order irregularity after PMMA IOL implantation.

Acrylic Resins↗
PubMed2001

Popperian falsification of methods of assessing surgically induced astigmatism.

To test several methods of assessing surgically induced astigmatism (SIA). Department of Ophthalmology, Arhus University Hospital, Arhus, Denmark. Assessment methods can be divided into 3 groups. Group 1 includes methods that consider only astigmatic magnitude and disregard astigmatic direction, such as the algebraic and simple subtraction methods. Group 2 can be termed "astigmatic magnitude not considering axis" and includes several almost identical techniques known as the methods of Naylor, Jaffe, Kaye, Holladay, and Olsen. Group 3 includes Naeser polar value analysis and the methods later described by Alpins and Holladay. The methods were tested in situations in which the expected result was known. When this result was not produced, the specific assessment method was considered falsified in a classical Popperian manner. The simple falsification experiments revealed that the methods in Groups 1 and 2 are erroneous. Mathematical analysis disclosed that the methods in Group 3 are similar, although derived from different concepts. The algebraic, simple subtraction, astigmatic magnitude not considering axis, and vector decomposition methods for assessment of SIA are erroneous and should not be used. The Naeser, Alpins, and Holladay methods are identical and in agreement with current research in optometry.

Astigmatism↗
PubMed2002

Implantation of spheric phakic posterior chamber intraocular lenses in astigmatic eyes.

PURPOSE: To evaluate the simultaneous correction of spherical and cylindrical ametropia through implantation of phakic posterior chamber (PC) intraocular lenses (IOLs) combined with a limbal incision. SETTING: Eye Department, Schlosspark-Klinik, Charité University Berlin, Berlin, Germany. METHODS: In 5 hyperopic and 7 myopic eyes with varying astigmatic measurements, a refractive correction was achieved by implanting phakic PC IOLs (Staar Surgical Co.) and performing limbal incisions of different lengths. The incisions were placed approximately 1.0 mm from the limbus with a mean depth of 600 microm and a length of 6.0 mm +/- 0.9 (SD). The phakic PC IOLs were implanted after the limbal incisions were placed. RESULTS: In the 5 hyperopic eyes, the astigmatism decreased from 2.7 diopters (D) preoperatively to 0.5 D at a mean of 7.5 +/- 1.7 months without alteration of the axis of highest bowing. In the 7 myopic eyes, it decreased from 2.2 D preoperatively to 0.7 D at 7.2 +/- 2.6 months. In 3 hyperopic eyes and 1 myopic eye, the limbal incisions were repeated. CONCLUSIONS: The observed mean postoperative spherical equivalent was close to emmetropia. Repeat incisions were necessary in eyes exhibiting astigmatism greater than 2.5 D. The advantage of limbal incisions in combination with phakic PC IOL implantation is demonstrated not only by the astigmatic reduction but also by the axis stability. It will be interesting to see whether toric phakic lenses can achieve the same postoperative results, especially in axis stability and reduction of higher degrees of astigmatism.

Adult↗
PubMed2002

Minimal astigmatism after sutureless planned extracapsular cataract extraction.

PURPOSE: To evaluate astigmatism after mini-nuc extracapsular cataract extraction (ECCE) in which a chevron incision is enlarged to 6.0 to 7.0 mm for easier nucleus removal and to compare the results with those using a 5.0 mm incision. SETTING: Department of Ophthalmology, The Edith Wolfson Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Holon, Israel. METHODS: Thirty eyes of 29 patients were enrolled in this study. Keratometry was performed preoperatively and 3 to 9 months postoperatively. The incision length was 6.0 mm in 6 eyes, 6.5 mm in 10 eyes, and 7.0 mm in 14 eyes that had mature cataract. RESULTS: The mean induced astigmatism calculated by simple subtraction was 0.12 diopter (D) +/- 0.51 (SD), 0.16 +/- 0.98 D, and 0.67 +/- 0.91 D for the 6.0 mm, 6.5 mm, and 7.0 mm incision, respectively. By vector analysis, the mean induced astigmatism was 0.60 +/- 0.30 D, 0.75 +/- 0.67 D, and 1.36 +/- 0.77 D, respectively. Results by both methods showed no significant difference between the previously reported 5.0 mm incision and the 6.0 mm and 6.5 mm incisions. The 7.0 mm group had statistically significantly greater induced astigmatism than the 5.0 mm group (P =.01, simple subtraction; P =.002, vector analysis). CONCLUSIONS: Enlarging the size of the chevron incision up to 7.0 mm resulted in a small increase in induced astigmatism. The enlarged incision simplified the operative technique.

Adult↗
PubMed2002

Laser in situ keratomileusis for myopia and compound myopic astigmatism using the Technolas 217 scanning-spot laser.

PURPOSE: To evaluate the safety, efficacy, predictability, and visual results of laser in situ keratomileusis (LASIK) using the Bausch & Lomb Technolas(R) 217 scanning-spot laser for the treatment of myopia and compound myopic astigmatism. SETTING: Stanford Eye Laser Center, Stanford, California, USA. METHODS: In a prospective study, 110 eyes of 58 patients with a mean spherical equivalent (SE) of -4.87 diopters (D) +/- 2.5 (SD) (range -1.0 to -11.4 D) had LASIK for myopia and compound myopic astigmatism using the Technolas 217 scanning-spot laser. The primary outcome variables included preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), achieved versus attempted correction, vector analysis of astigmatism, and complications. RESULTS: One hundred ten eyes were available for analysis at 3 months. The mean SE refraction was reduced 95% (mean -0.23 +/- 0.4 D), and astigmatism was reduced 70% (mean 0.28 +/- 0.3 D). One day postoperatively, 100% of eyes had a UCVA of 20/40 or better, 96% had 20/25 or better, 77% had 20/20 or better, and 39% had 20/15 or better. At the 3-month examination, 100% of eyes had a UCVA of 20/40 or better, 95% had 20/25 or better, 83% had 20/20 or better, and 48% had 20/15 or better. Ninety percent of eyes were within +/-0.5 D of emmetropia. No eye lost 2 or more lines of BSCVA. CONCLUSIONS: The Technolas 217 scanning-spot laser produced excellent postoperative UCVA and BSCVA. It was predictable, safe, and effective for the treatment of myopia and compound myopic astigmatism. Long-term follow-up is needed to assess the stability of the procedure.

Adult↗
PubMed1994

Effect of pupil size and astigmatism on contrast acuity with monofocal and bifocal intraocular lenses.

We conducted a bicenter study to evaluate the effect of pupil size and corneal astigmatism on best corrected contrast acuity (BCCA) in patients with the True Vista bifocal intraocular lens (IOL) and compared the results with those in a matched group of monofocal patients. Best corrected contrast acuity was measured using the Regan Charts (96%, 50%, 25%, 11%) at four pupil sizes (2.0, 2.5, 3.5, 6.0 mm) in three groups (Group 1: corneal astigmatism 0-0.50 D [n = 11]; Group 2: 0.75-1.50 D [n = 11]; Group 3: 1.75-2.50 D [n = 4]). In monofocal eyes, BCCA between these astigmatic groups did not differ significantly at any contrast step or at any pupil size tested. However, BCCA decreased slightly with increasing pupil size in each group, and differences between 2.00 mm and 6.0 mm pupils were significant at each contrast level. In all bifocal groups, BCCA decreased significantly with increasing pupil size and also decreased with increasing corneal astigmatism; differences were significant at most pupil sizes and contrasts tested. In Group 1, BCCA was lower in eyes with bifocal IOLs than in eyes with monofocal IOLs at 25% and 11% contrast with a 2.5, 3.5, and 6.0 mm pupil; with a 2.0 mm pupil it did not differ significantly. In Groups 2 and 3, BCCA in eyes with bifocal IOLs was lower at all contrast steps and all pupil sizes tested. Our results indicate that corneal astigmatism in excess of 0.50 D reduces quality of vision in eyes with bifocal IOLs, while eyes with monofocal IOLs are not affected.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Comparison of the induced astigmatism after temporal clear corneal tunnel incisions of different sizes.

A prospective, randomized study compared the surgically induced astigmatism after 3.5 mm, 4.0 mm, and 5.0 mm temporal corneal tunnel incisions over six months. We studied 60 eyes of 60 patients who had phacoemulsification through a two-step clear corneal tunnel incision and implantation of one of three posterior chamber intraocular lenses (IOLs). Patients were divided into three groups of 20 each: Group A, cartridge injection of a foldable plate-haptic silicone IOL through a 3.5 mm self-sealing incision; Group B, cartridge injection of a disc silicone IOL through a 4.0 mm self-sealing incision; Group C, 5.0 mm optic poly(methyl methacrylate) IOL through a 5.0 mm incision with one radial suture. Corneal topography data were obtained using a computerized videokeratographic analysis system preoperatively and one week and six months postoperatively. Vector analysis was performed to calculate the surgically induced astigmatism. After the first postoperative week, mean induced astigmatism was 0.63 diopters (D) (+/- 0.41) in Group A, 0.64 D (+/- 0.35) in Group B, and 0.91 D (+/- 0.77) in Group C. After six months, it was 0.37 D (+/- 0.14) in Group A, 0.56 D (+/- 0.34) in Group B, and 0.70 D (+/- 0.50) in Group C. Surgically induced astigmatism was significantly lower in Group A than in Group B (P < .05) and Group C (P < .005) after six months. Vector analysis demonstrated that temporal corneal tunnel incisions induced clinically minimal astigmatism over six months postoperatively depending on incision size.

Aged↗
PubMed1991

Frown incision for minimizing induced astigmatism after small incision cataract surgery with rigid optic intraocular lens implantation.

A new technique, the frown incision, was developed and a series of 62 eyes with 6 mm and 7 mm incisions for intercapsular phacoemulsification and implantation of a 6 mm or 7 mm one-piece biconvex poly(methyl methacrylate) (PMMA) posterior chamber intraocular lens with single horizontal mattress suture closure was prospectively evaluated for induced astigmatism. A prior series of 34 eyes that had a similar procedure with 6 mm and 7 mm standard scleral pocket incisions closed with an infinity suture or a horizontal running single-knotted suture containing three loops was retrospectively reviewed and compared with the frown incision trial. Vector analysis calculations of diopters (D) of mean induced keratometric astigmatism for the frown incision versus the scleral pocket incision groups were 0.80 D versus 1.19 D (P = .0263) at one day; 0.74 D versus 1.03 D (P = .0547) at one week; 0.71 D versus 1.07 D (P = .0057) at four weeks; 0.84 D versus 1.15 D (P = .0072) at six months; 0.82 D versus 1.30 D (P = .0144) at one year. The frown incision group consistently had a lower standard deviation from the mean induced astigmatism than the scleral pocket incision group. Using regression analysis and Pearson product-moment correlations, the frown incision group had a higher degree of linear dependence of postoperative astigmatism on preoperative astigmatism. Recent modifications of the frown incision have reduced its chord length for insertion of any given optic size. Results suggest that the frown incision may provide many of the benefits of a 4 mm scleral pocket incision for flexible optic lenses.

Astigmatism↗
PubMed1990

Astigmatic keratotomy: a review of basic concepts with case reports.

Despite the use of small incisions, better wound closure, and other technical improvements in cataract and corneal surgery, astigmatism remains a problem for the cataract and refractive surgeon. Case reports illustrate the applicability of astigmatic keratotomy in post-cataract and idiopathic astigmatism. The basic concepts of corneal relaxing incisions are reviewed and the frequently misunderstood coupling phenomenon is explained in the light of the "law of elastic domes." Properly used, astigmatic keratotomy with coupling effectively corrects a wide variety of types of astigmatism.

Aged↗
PubMed1993

Changes in corneal shape after suture cutting using the argon laser for postoperative astigmatism following cataract extraction.

We studied the changes in corneal shape after suture cutting with an argon laser to reduce corneal astigmatism following cataract extraction. Sixty-two patients who exhibited high with-the-rule astigmatism (> 3 diopters [D]) following extracapsular lens extraction had argon laser suture cutting. The patients were classified into three groups: Group A comprised 30 patients whose sutures were cut two to three months after planned extracapsular cataract extraction (p-ECCE); Group B consisted of eight patients who had the same treatment five to nine months after p-ECCE; Group C comprised 24 patients who had the treatment one to two months after phacoemulsification (PE). The dioptric reduction of corneal astigmatism (the percent reduction of astigmatism) was 1.83 +/- 0.98 D (37.4 +/- 18.3%) in Group A, 3.20 +/- 2.35 D (55.6 +/- 34.4%) in Group B, and 2.08 +/- 1.20 D (41.4 +/- 20.4%) in Group C. There was no statistical significance in the dioptric reduction and the percent reduction among Groups A, B, and C. This suggests that the wound size and time of cutting are not directly correlated to the effect of argon laser suture cutting. To examine the relationship between the effect and changes in corneal shape from suture cutting, we divided the patients into two subgroups; one was Subgroup (+) in which the percent reduction of astigmatism was above 25%; the other was Subgroup (-) in which the percent reduction was below 25%.(ABSTRACT TRUNCATED AT 250 WORDS)

Astigmatism↗
PubMed1988

Long-term course of surgically induced astigmatism.

We performed an analysis of surgically induced astigmatism in 229 cases of extracapsular cataract extraction and posterior chamber lens implantation. The average length of follow-up for patients in this study was 34.4 months (2.87 years). We found that surgically induced astigmatism continued to change for at least three years after surgery. The preoperative astigmatism was found to have only minimal effect on the postoperative astigmatism if the corneal curvature was controlled with keratometry at the time of surgery. The optimal amount of with-the-rule astigmatism at three to five weeks postoperatively was found to be 0.75 diopter to 1.25 diopters for one surgeon and surgical technique.

Adult↗
PubMed1996

Excimer laser photorefractive keratectomy using an erodible mask to treat myopic astigmatism.

PURPOSE: To evaluate the results of excimer laser photorefractive keratectomy (PRK) using an erodible mask to treat myopic astigmatism. SETTING: Douglas Memorial Hospital Medical Centre, Fore Erie, Ontario, Canada. METHODS: Photorefractive keratectomy was done on 25 consecutive eyes of 25 patients with myopic astigmatism using the OmniMed excimer laser and a compound single-use myopic erodible mask manufactured to produce a specific spherical and cylindrical correction for each individual patient. Follow-up ranged from 6 months for 25 patients to 1 year for 5 patients. RESULTS: Six months after PRK, the mean preoperative sphere of -7.46 diopters (D) decreased to -0.17 D and the mean preoperative cylinder of 2.31 D dropped to 0.69 D; 73% of astigmatism was corrected. In the five eyes followed for 1 year, 94% of astigmatism was corrected. Correction of the myopic component was less predictable, with a wider than anticipated range of overcorrection. CONCLUSIONS: Excimer laser PRK successfully corrected myopic astigmatism in patients with low and high myopia. The less predictable myopia results may have been secondary to increased procedure time, corneal dehydration, and difficulty in patient fixation and thus alignment.

Adult↗
PubMed1996

Arcuate keratotomy to correct naturally occurring astigmatism.

PURPOSE: To evaluate retrospectively the safety, efficacy, and complications of arcuate keratotomy (AK) in correcting naturally occurring astigmatism. SETTING: Laser Ultravision Institute, Montreal, Canada. METHODS: Surgically induced refractive change was evaluated in 25 eyes of 15 patients with naturally occurring astigmatism. All patients had mixed or compound myopic astigmatism and were treated with AK alone or both AK and radial keratotomy (RK). Minimum follow-up of 24 months was necessary for inclusion in this study. We used vector analysis to evaluate the refractive and keratometric astigmatic change at 1 month and 1 and 2 years. RESULTS: Ten eyes (40%) had AK only and 15 eyes (60%), both AK and RK. It was necessary to redeepen the original incisions in 21 eyes (84%). All patients had improved uncorrected visual acuity postoperatively. The reduction in refractive cylinder, quantified by vector analysis, was significant. Two years postoperatively, mean reduction was 3.30 diopters (D) +/- 1.32 (SD) in eyes that had AK alone and 2.71 +/- 1.53 D in eyes that had both AK and RK. CONCLUSION: Arcuate keratotomy is an effective and safe method for correcting naturally occurring astigmatism. Further analysis of this series of patients is planned.

Adult↗
PubMed1997

Photoastigmatic refractive keratectomy for primary treatment and revision of myopic astigmatism.

PURPOSE: To evaluate the results in 43 eyes treated with a rotating mask for myopic astigmatism and followed for up to 1 year. SETTING: Lucerne Eye Clinic, Cantonal Hospital, Lucerne, Switzerland. METHODS: Thirty-two patients (42 eyes) were selected to have photoastigmatic refractive keratectomy (PARK). In 33% (14 eyes), this treatment was the second or third ablation. The Aesculap Meditec MEL 60 excimer laser was operated in toe scanning slit mode, and a rotating mask was used. To evaluate cylindrical shaping, vector analysis was performed. RESULTS: One year after PARK, mean uncorrected visual acuity in all patients (26 eyes) improved from 20/160 preoperatively to 20/40. Surgically induced astigmatism in 20 of 26 eyes (77%) was within +/- 1.00 diopter (D) of the targeted induced astigmatism. At 1 year, 81% of patients who had primary excimer laser treatment for myopic astigmatism equivalent to -10.00 D or less were within +/- 1.00 D of target refraction compared with 44% of re-treated eyes. CONCLUSION: The result of PARK in eyes with low to moderate degrees of myopic astigmatism was satisfactory. However, in eyes with extensive scarring and wound healing activity after the first ablation, re-treatment was less predictable.

Adult↗
PubMed1997

Treatment of hyperopic astigmatism.

PURPOSE: To analyze the results after laser-assisted in situ keratomileusis (LASIK) treatment for positive cylinder at the flattest meridian. SETTING: Instituto de la Visión, Buenos Aires, Argentina. METHODS: A prospective, nonrandomized study was conducted. Patients were divided into three groups: (1) simple hyperopic astigmatism (SHA); 15 eyes with a mean preoperative cylinder of +3.37 diopters (D) +/- 1.62 (SD); compound hyperopic astigmatism (CHA); 75 eyes with a mean preoperative cylinder of +3.34 +/- 1.39 D; (3) mixed astigmatism (MA); 73 eyes with a mean preoperative cylinder of +3.45 +/- 2.15 D. In all eyes, treatment of the cylinder was performed at the flattest meridian by LASIK using the Chiron-Technolas Keracor 116/117 laser. The following parameters were analyzed over time: uncorrected visual acuity; best corrected visual acuity; correction of the spherical equivalent and the cylinder; lines of visual acuity gained and lost. RESULTS: Six months after the procedure, refractive cylinder was reduced to +0.58 +/- 1.22 D in the SHA group, +0.12 +/- 1.23 D in the CHA group, and -0.11 +/- 1.28 D in the MA group. Uncorrected visual acuities were 20/20 or 20/25 in 66.7, 60.4, and 76.5% of the groups, respectively. CONCLUSIONS: Use of the LASIK technique with the Keracor laser to treat positive cylinder at the flattest meridian corrected simple and compound hyperopic astigmatism and mixed astigmatism with good predictability and safety. This treatment has not produced a hyperopic refractive change at the opposite meridian.

Adult↗
PubMed1997

Computerized topography of selective versus all-suture release to manage high astigmatism after cataract surgery.

PURPOSE: To compare the efficacy of selective suture release (SSR) with all-suture release (ASR) in controlling corneal astigmatism after cataract surgery. SETTING: Sight Saver's Cornea Training Centre, L.V. Prasad Eye Institute, Hyderabad, India. METHODS: This prospective, randomized study evaluated the effect on astigmatism of two techniques of suture release in 30 patients with more than 3.00 diopters (D) of corneal astigmatism after cataract surgery. All patients had interrupted sutures with well-healed wounds. Fifteen patients had ASR irrespective of the location of the steep meridian. In the other 15, only the suture located in the steep meridian was selectively released. The pattern of decay of astigmatism after suture release was studied using computerized videokeratography. RESULTS: Mean pretreatment corneal cylinder was 6.30 D +/- 2.72 (SD) in the ASR group and 6.95 +/- 1.67 D in the SSR group. In the ASR group, corneal cylinder dropped to 3.70 +/- 1.15 D immediately after suture release and further decreased to 1.82 +/- 0.66 D at 1 week (P < .001). In the SSR group, astigmatism swung erratically to the adjoining sutures and decreased unpredictably at an average of 1.32 +/- 2.00 D with each suture release. CONCLUSION: The ASR technique was more predictable and less cumbersome than the SSR method.

Aged↗
PubMedDate not supplied

Radial and astigmatic keratotomy experience by residents and fellows at a teaching institution.

PURPOSE: To retrospectively study 30 cases of radial and astigmatic keratotomy performed by third-year ophthalmology residents and cornea fellows. SETTING: Tulane University Medical Center, New Orleans, Louisiana. METHODS: Patients were selected based on correction for stable myopia without or with astigmatism. Four or eight radial incisions were made using the Russian (uphill) method. The astigmatic cuts were straight transverse. RESULTS: Uncorrected visual acuity postoperatively was 20/40 or better in 28 eyes (93%). Two patients(visual acuity 20/50 and 20/70) were scheduled for secondary procedures but were lost to follow-up. Complications included three microperforations without sequelae. CONCLUSION: Radial and astigmatic keratotomy to correct myopia or myopia with astigmatism can be safe and effective in the hands of a beginning surgeon.

Adolescent↗
PubMed1997

Two-incision radial keratotomy for low myopia with astigmatism.

PURPOSE: To evaluate the effectiveness of two-incision radial keratotomy (RK) in correcting low-magnitude refractive myopic astigmatism. SETTING: Two clinical study sites, one in St. Louis, Missouri, USA, the other in Caracas, Venezuela. METHODS: Fifty-seven eyes of 43 patients with low-magnitude myopic astigmatism had two-incision RK at one of two clinical study sites. In the initial phase of this series, 10 eyes with amblyopia at the 20/30 level had surgery at one center. Refractive keratotomy was performed with the radial incision placed in the plus cylinder axis of refraction. This axis was verified as the meridian of greatest corneal curvature by standard keratometry and computer-assisted corneal topographic analysis. Two eyes received a second operation (enhancement). RESULTS: Mean follow-up was 11.1 months (range 6 to 12 months). Mean preoperative and postoperative myopic spherical equivalent measured -1.42 diopters (D) +/- 0.51 (SD) and -0.14 +/- 0.39 D, respectively; the mean reduction was 1.28 +/- 0.59 D (P = .0001). Mean preoperative and postoperative refractive astigmatism was 1.41 +/- 0.45 D and 0.48 +/- 0.33 D, respectively (P = .0001). Mean preoperative and postoperative keratometric astigmatism was 1.26 +/- 0.54 D and 0.31 +/- 0.35 D, respectively, a mean reduction of 0.95 D (P = .0001). The surgical meridian was flattened by an average of 2.06 D by keratometry and the orthogonal meridian, by an average of 1.10 D. Preoperative uncorrected visual acuity (UCVA) was 20/40 or better in five (9%) eyes (range counting fingers to 20/40). Postoperative UCVA acuity was 20/40 or better in all eyes (mean acuity 20/25). In the nonamblyopic subgroup mean postoperative UCVA was 20/24. CONCLUSIONS: A limited number of radial incisions placed in the topographically confirmed axis of greatest curvature are effective in the treatment of low-magnitude myopic astigmatism.

Adolescent↗