Underwent LASIK Surgery Research Articles

Advancements in Laser Eye Surgery Through Sectional Study

Background: Laser in situ corneal surgery (LASIK) This technique has been considered as the most widespread and most widely performed refractive intervention in eye surgery in the world, which may show a high satisfaction index among patients after surgery. Objective: This study aimed to evaluate the results of vision quality for patients suffering from myopia and astigmatism after LASIK surgery. Patients and methods: We conducted a cross-sectional study of 74 patients ages 28-54 who suffered from myopia and astigmatism who underwent LASIK surgery. This study extended from February 16, 2022, to September 9, 2023. This study determined the importance of LASIK surgery in improving the visual function of patients in the long term in terms of satisfaction and happiness after surgery, functional improvement, and achieving the expected quality of vision. Results: Our results found that the percentage of males, which included 47 patients, was greater than that of females, which included 27 patients. The data for both surgery time were (22.46 ± 0.8) minutes, and corneal thickness was (498 ± 4.0 microns, recovery time was (3.6 ± 2.4) days. Our outcomes found that the surgery to be a good option, and it was 98%. The main goal was achieved. It was 96%. They were satisfied with the result. It was 95.40%. Happiness after LASIK was 99%. Conclusion: LASIK surgery has shown that the surgical procedure is the most healing, the quickest to perform, and the safest, which increases functional improvement and which contributes significantly.
 Great quality optical resolution. Our results confirm that there is great patient satisfaction with LASIK surgery, which is attributed to the quality of this surgery, which improves visual ability in a safer and more accurate way.

Comparative analysis of local cytokine profile and corneal regenerator process after LASIK and Femto-LASIK surgery

Introduction. The existing data in the scientific literature on the role of cytokines as a special biological system, a function of which is the local regulation of regeneration, justifies the relevance of research task in this direction.Purpose: to study changes of the cytokines concentration in the lacrimal fluid in patients after excimer laser vision correction with LASIK and Femto-LASIK surgery and its correlation with postoperative patients’ parameters.Methods. The study included 20 patients (40 eyes) with mild myopia and compound myopic astigmatism. The prospective study was carried out in January-August 2022. The patients were divided into 2 groups. In the comparison group (n = 10, 20 eyes) patients underwent LASIK surgery, in the main one (n = 10, 20 eyes) – Femto-LASIK. During the study, the tear fluid was taken and its further biochemical study was carried out to determine the level of cytokines: IL-1β, IL-8, TNF-α.Results. In the main group, frequency detection of the cytokine IL-1β that is the main pro-inflammatory agent was 80%. In the comparison group it was detected in 90% of the tear fluid samples. Mean IL-1β values were the highest in the comparison LASIK group. Mean TNF-α scores were the highest in the comparison LASIK group. In the same time, differences of the average values between the main and comparison groups were statistically significant (p < 0.05). Mean IL-8 values were the highest in the main group who underwent Femto-LASIK surgery.Conclusion. The course of regenerative process in patients after excimer laser vision correction depends on concentration of the pro-inflammatory cytokines IL-1β and TNF-α and the anti-inflammatory cytokine IL-8. Based on this, a higher level of the pro-inflammatory cytokines in the lacrimal fluid determines the prolongation of pain relief and epithelialization after surgery.

Hyperopic LASIK Enhanced by Pharmacological Treatment of Presbyopia.

Purpose: Regression of the refractive outcome is a major concern of LASIK procedures mainly in presbyopic patients. The purpose of this study was to evaluate the long-term efficacy of the pharmacological treatment of presbyopia performed with Benozzi's method, in combination with hyperopic LASIK surgery in presbyopic population. Methods: A nonrandomized case series was developed, including presbyopic patients who underwent bilateral "Hyperopic LASIK surgery" and were pharmacologically treated with Benozzi's Method from January 2011 to August 2018, with at least 2 years of follow-up, at two private ophthalmological clinics of Argentina. Main outcomes were spherical equivalent (SE), uncorrected distance visual acuity (UDVA), and uncorrected near visual acuity (UNVA). Measurements were evaluated at baseline and postoperative at 1 month (without Benozzi's treatment), 2 months (starting with Benozzi's treatment), and 2 years. The SE stability across the time was statistically compared. Results: A total of 84 eyes of 42 patients, with a mean age at the time of the surgery of 51.07 ± 4.5 (42-59), were found following 2 years of follow-up. Patients have improved and maintained UDVA, achieving Jaeger 1 in the second postoperative month, which was maintained up to the last year of follow-up. Refractive stability across the time is observed comparing first month after surgery with the last year of follow-up, without statistical significant difference (p: 0.11). Conclusion: Hyperopic presbyopic patients that underwent LASIK surgery and 1 month after surgery started with the pharmacological treatment of presbyopia (Benozzi's method) results in excellent UNVA and UDVA that is stable over time without refractive regression.

Pentacam versus anterior segment OCT in measuring intended versus achieved ablation depth post-myopic LASIK correction

BackgroundAccurate quantitative measurements of central corneal thickness (CCT) provide valuable, clinical information for preoperative assessment, surgical planning, and follow-up in myopic patients who have undergone LASIK correction. Typically, an ultrasound is used to measure such parameters. However, noncontact devices such as the Visante anterior segment optical coherence tomographer [AS-optical coherence tomography (OCT)] and Pentacam are becoming more popular to measure ocular parameters. It is important to assess the level of similarity between these two optical devices to compare between the intended and achieved ablation depth after LASIK procedures in cases of myopia and myopic astigmatism.MethodsThis cross-sectional, prospective study included 80 eyes of 40 patients attending Beni-Suef University Hospital between November 2018 and November 2019. All patients underwent LASIK surgery for the correction of myopia with or without myopic astigmatism with spherical equivalent ranging from − 1.5 to − 12 diopters.ResultsNo statistically significant difference was observed between the intended ablation depth and the clinically measured ablation depth calculated by Pentacam and AS-OCT 3 months after surgery (P > 0.05).ConclusionWhen planning corneal refraction surgery, ablation depth readouts calculated by the computer software of the excimer laser used in this study are reliable. Both Pentacam and AS-OCT are accurate, sensitive, and specific in measuring the CCT and calculating ablation depth. Pentacam provides slightly higher accuracy and sensitivity compared with AS-OCT. LASIK is a safe, predictable, and effective procedure in the treatment of simple myopia and myopic astigmatism.

Elevated intraocular pressure‐induced interlamellar keratitis in a patient with LASIK surgery 14 years ago

AbstractPurposeTo describe a case of interlamellar keratitis induced by elevated intraocular pressure (IOP) in a patient with a history of LASIK surgery and the importance of having a strong diagnostic suspicion for establishing adequate treatment.MethodsIntraocular pressure‐induced interlamellar keratitis is one of the potential complications of LASIK refractive surgery. The cases described generally occur a few months after surgery although there are some cases that have been described several years after surgery, usually in a context of uveitis and corticosteroid treatment or silent glaucoma. We present a case of 43‐year‐old woman who came to the emergency room with visual acuity (VA) impairment in the left eye in the setting of elevated intraocular pressure‐induced interlamellar keratitis secondary to the intravitreal corticosteroid implant in her left eye due to a diabetic retinopathy. She underwent LASIK surgery 14 years ago.ResultsThe treatment was based on lowering the intraocular pressure. Oral acetazolamide and topical timolol, bimatoprost and brinzolamide were used. The patient recovered her baseline VA and the IOP were properly controlled posteriorly.ConclusionsThis case shows the importance of considering this diagnosis in patients with corneal haze, elevated intraocular pressure and a history of LASIK surgery to establish an adequate treatment. A full recovery is expected.Bibliography1. Galal A, Artola A, Belda J, (2006) Interface corneal edema secondary to steroid‐induced elevation of intraocular pressure simulating diffuse lamellar keratitis. Journal of refractive surgery.2. Lee V, Sulewski M, Zaidi A (2010) Elevated Intraocular Pressure–Induced Interlamellar Stromal Keratitis Occurring 9 Years After Laser In Situ Keratomileusis. Corneal Journal.3. Lyle W, Jin G, Jin Y (2003) Interface fluid after laser in situ keratomileusis. Journal of refractive surgery.4. Tourtas T, Kopsachilis N, Meiller R, et al. (2010). Pressure‐Induced Interlamellar Stromal Keratitis After Laser In Situ Keratomileusis. Corneal Journal.

Evaluate the Prevalence, Natural Course, and Final Visual Acuity in Patients with Stages III or IV of Diffuse Lamellar Keratitis Following Laser in Situ Keratomileusis

Background: And aim: The prevalence of DLK has been reported differently in different centers based onits severity. Hence, the aim of present study was evaluate the prevalence, natural course, and final visualacuity in patients with stages III or IV of diffuse lamellar keratitis following laser in situ keratomileusis.Methods: In the present descriptive study, 3941 eyes files from 2125 patients underwent LASIK surgery;were examined. All patients had a complete ophthalmologic examination before LASIK and had suitableconditions for LASIK.Result: Among the studied cases, 39 eyes (0.98%), out of 16 patients (0.75). The mean time intervalbetween LASIK and DLK diagnosis was 3± 2.4 days. A history of allergy was negative in all patients. Themean post-operative spherical refractive error in all eyes was in the range of 1 diopters and the averagecylindrical refractive error in 33 eyes was -0.66±1.2 diopters. The mean of final spherical refraction in34 eyes was 0.5±1.2 diopter and the mean of final cylindrical refraction in 35 eyes was -0.75±1.3 diopter.Severe turbidity at the flap surface in the first week decreased over time in all patients with stage III and IVDLK. So that only in four eyes (10.25%)Conclusion: The prevalence of stages III and IV in DLK is negligible compared to the large number ofLASIK procedures and all patients respond well to topical and systemic corticosteroid therapy.

Analysis of OPD-Scan and Pentacam Parameters for Early Keratoconus Detection

PURPOSE: To evaluate Pentacam and OPD-Scan parameters in the early detection of keratoconus. Retrospective case-control study. Case group included 50 clinically unaffected fellow eyes diagnosed with asymmetric keratoconus showing subtle qualitative changes at the 0.5-D sensitivity OPD-Scan scale, as well as normal anterior and back elevation difference map at Belin/Ambrósio enhanced ectasia display (BAD) at the Pentacam. Control group included 172 normal eyes that underwent Lasik surgery and presented no complications throughout the 2-year follow-up period. OPD-Scan and Pentacam parameters were compared, calculating sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). A multivariate analysis was performed using Pentacam or OPD-Scan variables, and a model using variables of both devices. Pentacam variables with AUC ≥0.8 were keratoconus index (0.85), index of height decentration (0.81), and overall deviation at BAD (0.8). OPD-Scan variables with AUC ≥0.8 were keratoconus prediction index (0.83), surface asymmetry index (0.83), and total of higher-order trefoil aberration (0.8). In the multivariate analysis, the AUC was 0.85 in the case of OPD-Scan whereas it was 0.89 in the case of Pentacam. When combining all variables from the 2 devices, the AUC was 0.93, with a sensitivity of 82% and a specificity of 94%. Several parameters of OPD-Scan and Pentacam can be useful to differentiate cases from normal control eyes, demonstrating even better results when combining parameters of both devices. Anterior corneal indexes were the most important parameters to discriminate both groups.

Nearwork-induced transient myopia and accommodation function before and after laser-assisted in situ keratomileusis surgery.

Purpose:To assess the change in Near Induced Transient Myopia (NITM) and other accommodation parameters, before and after undergoing LASIK surgery for myopia correction.Methods:Twenty-nine myopic subjects were recruited from a tertiary eye hospital in India. Age range was 21 to 35 years with an average age of 26.1 ± 3.5 years. Mean spherical equivalent was –3.86 D ± 1.50 D presurgery. NITM, lag of accommodation, near point of convergence (NPC), accommodative amplitude (AA), and binocular near accommodative facility (AF) were measured. All data were collected 21 days prior to and 30 days after LASIK surgery.Results:NITM, lag of accommodation and amplitude of accommodation were significantly lower (NITM -0.05 ± 0.15, Lag 0.38 ± 0.38, AA 10.27 ± 2.24) after surgery when compared to before (NITM 0.26 ± 0.12, Lag 0.77 ± 0.51, AA 12.18 ± 2.02; P < 0.001). Accommodative facility increased and near point of convergence was significantly more distal following surgery (AF 10.70 ± 2.29, NPC 7.96 ± 1.63) when compared to prior (AF 8.65 ± 2.74, NPC 5.62 ± 1.71; P < 0.001).Conclusion:Significant changes in NITM and accommodation function should be expected in the short term following LASIK surgery. This study supports the importance of evaluating accommodative parameters and patient counselling prior to and following refractive surgery.

Excimer laser programming of refractive astigmatism vs. anterior corneal astigmatism in the case of ocular residual astigmatism (ORA)

To determine whether manifest refractive astigmatism (RA) or anterior corneal astigmatism (CA) is the best value for excimer laser programming in cases of ocular residual astigmatism (ORA). Patients who had undergone LASIK surgery with a disagreement between manifest refractive and corneal cylinder (ocular residual astigmatism ORA)>0.75 D were included retrospectively in this study. We calculated target induced astigmatism vector (TIA), surgically induced astigmatism vector (SIA), difference vector between the astigmatism correction programmed in the excimer laser and refractive astigmatism (DVRA), difference vector between the astigmatism correction programmed in the excimer laser and corneal astigmatism (DVCA) and difference vector between TIA and SIA (DV), by the Alpins method. Vectorial differences between DV and DVRA, and between DV and DVCA, were then calculated to determine whether RA or CA was closest to the ideal cylinder for laser programming. Of a total of 104 eyes undergoing LASIK, 22 eyes of 12 patients (21.1%) had an ORA>0.75 D and were included. Mean ORA was 0.9±0.2 D and mean postoperative subjective cylinder was 0.45 D. The DV-DVRA difference vector was 0.57±0.2 D, and the DV-DVCA difference vector was 0.86±0.4 D (P=0.02). RA was closer than CA to the ideal astigmatism correction. In cases of discrepancy between manifest astigmatism and corneal astigmatism, correction of manifest refractive astigmatism seems to give a better refractive result.

Corneal epithelial thickness one year after myopic LASIK surgery, measured by anterior segment optical coherence tomography combined with Placido disk

Abstract Objective To compare corneal epithelial thickness (CET) between patients who underwent LASIK surgery for the correction of myopia at least one year ago and healthy subjects. Methods A retrospective observational study was conducted that included 93 healthy subjects (186 eyes) and 26 subjects (52 eyes) that underwent myopic LASIK surgery. OCT-SA, combined with Placido disk, was performed on all subjects, and CET maps were measured. Statistical analysis was performed to analyze differences between groups. Multivariate analysis was also performed to look for possible predictors of final CET. Results There was no statistically significant differences between the groups in the demographic (age, sex) or anterior segment parameters (spherical equivalent, pachymetry) (all p > 0.05). Statistically significant differences (p Conclusions CET values measured by the OCT-SA were higher in patients that underwent LASIK surgery ≥1 year. The only variable that correlated with the CET after LASIK was the time elapsed since surgery. CET changes should be taken into consideration when planning refractive surgery due to its implications on the final outcome.

Comparative Study of Corneal Thickness before and after FemtoLasik Surgery with Pentacam® AXL and Ultrasound Device (Tomey SP-100)

Aims: The purpose of our research is to evaluate corneal thickness, pre-operative and post-operatively after FemtoLasik surgery, using “Pentacam® AXL” and Ultrasound device. To evaluate the correlation of the two devices and their interchangeability.&#x0D; Sample and Study Design: Our data includes 70 eyes of patients, age 19- 59 years, who undergone Lasik surgery for myopia. The data concerned pre-operative and post-operative central corneal pachymetry using Ultrasound pachymeter (Tomey SP-100) and “Pentacam® AXL”.&#x0D; Methodology - Place and Duration of Study: University of West Attica Dept Biomedical Science Course Optics &amp; Optometry in collaboration with Private Ophthalmology Clinic “Athens Opthalologiko” during the period between May 2018 until September 2018. In this study, a comparison of data taken with Pentacam and Ultrasound was performed concerning central corneal thickness before and after FemtoLasik to evaluate the correlation of these devices. All the FemtoLasik surgeries were performed by the same experienced surgeon in order to ensure good repeatability of surgical procedures and all the patients selected had healthy eyes with no other ophthalmic pathology or systemic disease and myopia ranging from -1.00 to 9.25 Diopters. All patients were measured one month after FemtoLasik having achieved 6/6 visual acuity.&#x0D; Results: Central corneal thickness before FemtoLasik measured by ultrasound device had an arithmetic mean value of 552.43 μm ± SD 26.95. The thickness preoperatively with “Pentacam” had an arithmetic mean value of 556.26 μm ± SD 27.82. The corneal thickness after Lasik measured by ultrasound device had an arithmetic mean value of 493.21μm ± SD 36.30, while for “Pentacam” the arithmetic mean value was 499.07μm ± SD 36.17. The two devices correlate strongly (0.9218 and 0.9986 respectively with significant level P&lt;0,0001)&#x0D; Conclusion: Our conclusions after statistical analysis are that Ultrasound pachymetry and “Pentacam” topography correlated strong.

Laser in situ keratomileusis (LASİK) in patients with superior steepening on corneal topography: Is it safe and predictable?

Attention is usually given to inferior steepening on corneal topography in the evaluation of a patient's suitability for LASIK surgery. The aim of this study is to investigate long-term refractive results with superior steepening. Patients who underwent LASIK surgery between 2015 and 2019 in our refractive surgery department were retrospectively reviewed. The patients with a ≥ 1.0 D superior-inferior (S-I) quadrant difference in the tangential map, using a Scheimpflug camera with a Placido disc topographer (Sirius), were included in the study. Preoperative and postoperative best-corrected and uncorrected visual acuity (Snellen), cylindrical refraction values, and spherical equivalent (SE) values were compared. Adverse events were recorded. Fifty eyes of 28 patients participated in the study. The mean age of the patients was 27.5 ± 8.0 (19-59). Sixteen patients were female (57.1%), and 12 (42.8%) patients were male. The average follow-up time was 29.8 ± 11.1months (12-61). Average central corneal thickness was 549.4 ± 26.0 (498-602) μm. Average minimal corneal thickness was 549.1 ± 26.9 (497-598) μm. Preoperative S-I quadrant difference (D) was 1.87 ± 0.7 (1.0-3.99). Posterior elevation (Kvb) was 11.2 ± 1.9 (9-17) μm. The preoperative SE value was - 1.7 ± 2.1 (- 6.25-3.25) and improved to - 0.3 ± 0.44 D (- 1.25-0.75) (p < 0.001). Preoperative cylindrical refraction values were - 2.04 ± 1.7 (- 6.25-0), and postoperative values were - 0.47 ± 0.4 (- 2-0) D (p < 0.001). Uncorrected visual acuity was median 1.0 (0.4-1.0) with 38 eyes (76%) having 20/20 postoperative uncorrected visual acuity. No sight threatening complications or ectasia findings were observed during the 2years postoperative follow-up time. Abnormal corneal topographies with (S-I) asymmetry result in predictable results after LASIK.

Grosor epitelial corneal un año después de la cirugía de LASIK miópico, medido mediante tomografía de coherencia óptica de segmento anterior combinado con disco de Plácido

ObjectiveTo compare corneal epithelial thickness (CET) between patients who underwent LASIK surgery for the correction of myopia at least one year ago and healthy subjects. MethodsA retrospective observational study was conducted that included 93 healthy subjects (186eyes) and 26 subjects (52eyes) that underwent myopic LASIK surgery. OCT-SA, combined with Placido disk, was performed on all subjects, and CET maps were measured. Statistical analysis was performed to analyse differences between groups. Multivariate analysis was also performed to look for possible predictors of final CET. ResultsThere was no statistically significant differences between the groups in the demographic (age, sex) or anterior segment parameters (spherical equivalent, pachymetry) (all P>.05). Statistically significant differences (P<.05) were obtained between both groups when comparing CET, including central, internal, and external rings (higher in patients that underwent LASIK surgery ≥1year). With the exception of the time elapsed since surgery (P=.00), no correlation was found between the CET and age, sex, ablated dioptres, or other variables studied (P<.05). ConclusionsCET values measured by the OCT-SA were higher in patients that underwent LASIK surgery ≥1year. The only variable that correlated with the CET after LASIK was the time elapsed since surgery. CET changes should be taken into consideration when planning refractive surgery due to its implications on the final outcome.

Verification and measurement of the side-cut angle of corneal flap in patients undergoing LASIK surgery using FS 200 kHz femtosecond laser system versus conventional mechanical microkeratome.

Introduction: This is a prospective nonrandomized interventional clinical trial conducted to measure and verify the intended versus the achieved LASIK flap side-cut angle in two groups of patients, Femtosecond laser-assisted in-situ keratomileusis (FS-LASIK) using Wavelight FS200 (Alcon Laboratories Inc. Fort Worth, TX, USA) and the conventional mechanical microkeratme (Moria M2 90).Methods: This prospective clinical trial was conducted on 40 eyes of 20 patients (20 eyes in each group) in the interval between December 2017 and August 2018. Heidelberg anterior segment OCT was done for the patients 2 weeks postoperatively to measure the corneal flap side cut angle.Results: The achieved side-cut angles of all the patients in the first group (the femtosecond laser-assisted in-situ keratomileusis group) were equal to or more inverted than the intended angle (110–115°) in all the study candidates with a minimum angle (110°) and maximum angle (155°). Unlike the achieved side-cut angle in the second group (the mechanical microkeratome group) in which all the achieved side-cut angle were acute with a minimum angle (30°) and maximum angle (65°) which is more acute than the intended side-cut angle (70°).Conclusion: In our study we found that the femtoLASIK technology was capable of making the flap side-cut angle more obtuse than the intended angle, unlike the achieved flap side-cut angle done using the mechanical microkeratome which was more acute than the intended angle in 100% of cases.

Early Refractive and Clinical Outcomes of High-Myopic Photorefractive Keratectomy as an Alternative to LASIK Surgery in Eyes with High Preoperative Percentage of Tissue Altered.

Objective To analyze the safety and efficacy of high-myopic PRK as an alternative to LASIK surgery in patients with a high preoperative percentage tissue altered (PTA). Design Retrospective interventional case series. Participants Charts of 256 consecutive eyes that underwent PRK with application of mitomycin-C 0.02% for high myopia were retrospectively reviewed. Methods Refractive (refraction and refractive accuracy) and visual outcomes (uncorrected and corrected visual acuities), as well as occurrence of haze in the eyes with preoperative PTA expected to be higher than 40% with a 110-micron flap if undergoing LASIK surgery, were analyzed. Results Mean follow-up was 7.3 ± 4.8 months. A total of 187 of 256 eyes (73.0%) were included in the analysis because they were expected to have a PTA greater than 40%, should they have undergone LASIK surgery. The actual mean PTA of those eyes following PRK was 31.8 ± 2.2%, and none had a PTA ≥ 40%. UDVA of 20/16, 20/20, and 20/25 or better was achieved in 1.2% (2 eyes), 65.5% (112 eyes), and 85.4% (146 eyes), respectively. The percentage of eyes with postoperative SE within ±0.5 D and ±1.0 D of planned SE was 71% and 93%, respectively. None of the eyes lost 2 or more lines of CDVA. The rate of stromal haze, managed successfully with topical steroids only, was 4.8%. Conclusion High-myopic PRK with application of mitomycin-C in the eyes at risk of developing ectasia because of high preoperative PTA was demonstrated to be a safe and effective alternative to the LASIK procedure.

Induced De Novo Astigmatism After Hyperopic LASIK Versus Myopic LASIK Surgery in Nonastigmatic Eyes.

To compare the astigmatism induced surgically (SIA) by spherical hyperopic laser in situ keratomileusis (H-LASIK) versus myopic laser in situ keratomileusis (M-LASIK) in nonastigmatic eyes. A retrospective study of patients who underwent LASIK surgery between 2005 and 2014 at the Care-Vision Laser Center, Israel. We calculated the mean absolute SIA and performed risk factor analysis for induced astigmatism. Differences between H-LASIK and M-LASIK were analyzed. Eyes of 3877 patients who underwent M-LASIK and of 549 patients who underwent H-LASIK were nonastigmatic preoperatively and received a nonastigmatic treatment. Three months after surgery, hyperopic treatment induced more SIA (0.49 ± 0.48 D) than did myopic treatment (0.36 ± 0.4 D) (P < 0.001). In the H-LASIK group, the risk factors for induced astigmatism of >0.5 D were a higher preoperative refractive error (P = 0.003) and larger optical zone (7 vs. 6 mm). In the M-LASIK group, eyes with SIA >0.5 D tended to have steeper corneas preoperatively (43.8 ± 1.5 vs. 43.6 ± 1.4 D; P = 0.001), a higher spherical equivalent (-3.43 ± 1.53 Vs. -3.07 ± 1.45 P < 0.001), and smaller treatment zones (6 vs. 7 mm). In H-LASIK, the mean induced astigmatic axis was at 74.6 degrees. There was a consistent trend toward more SIA in H-LASIK and in higher refractive error correction. In H-LASIK larger optical zones induce more SIA and in M-LASIK smaller ones caused it.

Ocular residual astigmatism's effect on high myopic astigmatism LASIK surgery.

To analyze the effect of ocular residual astigmatism (ORA) on the effectiveness of LASIK for treating high myopic astigmatism. This is an observational, cross-sectional study. We studied 116 consecutive myopic eyes with -3 diopters (D) or more of astigmatism that underwent LASIK surgery. The magnitude of uncorrected residual refractive astigmatism 3 months postoperatively was measured. The mean preoperative cylinder was -4.0±0.83 D (range, -7.5 to -3 D) and the mean preoperative ORA was 0.82±0.5 D. The mean residual refractive cylinder 3 months postoperatively was -0.78±0.83 D (range, -3 to 0 D). No correlation was found between ORA and the refractive cylinder 3 months postoperatively (P=0.6). In eyes with high myopic astigmatism undergoing LASIK, ORA was not correlated with the residual postoperative cylinder.

The Economic Cost of Myopia in Adults Aged Over 40 Years in Singapore

To estimate the economic cost of myopia among adults aged 40 years and older in Singapore. A substudy of 113 Singaporean adults aged 40 years and older with myopia (spherical equivalent refraction of at least -0.5 diopters) in the population-based ancillary study of Singapore Chinese Eye Study (SCES) was conducted. A health expenditure questionnaire was used to assess the direct cost of myopia. A total of 113 (90.4%) of 125 myopic subjects participated in the survey. The mean cost was approximately SGD$900 (USD$709) per person per year. The lifetime per capita cost ranged from SGD$295 (USD$232) for those with 0 year's duration to SGD$21,616 (USD$17,020) for those with 80 years' duration. Costs of spectacles, contact lenses, and optometry services were the major cost drivers, contributing to an average of 65% of total costs. Seven subjects (6.2%) had undergone LASIK surgery, resulting in a cost of SGD$4891 (USD$3851) per patient per year. Three subjects (2.7%) reported annual costs of (SGD$33 or USD$26) for complications due to LASIK surgery or contact lenses. There was an increasing cost of myopia in adults who started to wear glasses at earlier ages. By applying our cost data to age-specific myopia prevalence data in the whole population in the country, the total cost was estimated to be approximately SGD$959 (USD$755) million per year in Singapore. Myopia is associated with substantial out-of-pocket expenditure, imposing considerable economic burden for patients. Myopia is a disorder with immense societal costs and public health impact.

Pilot study of hyperopic LASIK using the solid-state laser technology

To evaluate and report the visual, refractive, and aberrometric outcomes of LASIK for the correction of low to moderate hyperopia in a pilot group using a commercially available solid-state laser Prospective pilot study including 11 consecutive eyes with low to moderate hyperopia of six patients undergoing LASIK surgery using the Pulzar Z1 solid-state laser (CustomVis Laser Pty Ltd., currently CV Laser). Visual, refractive, and aberrometric changes were evaluated. Potential complications were evaluated as well. Mean follow-up time was 6.6 months (range, 3 to 11 months). A significant improvement in LogMAR uncorrected distance visual acuity (UDVA) was observed postoperatively (p = 0.01). No significant change was detected in LogMAR corrected distance visual acuity (CDVA) (p = 0.21). Postoperative LogMAR UDVA was 0.1 (about 20/25) or better in ten eyes (90.9 %). Mean overall efficacy and safety indices were 1.03 and 1.12. Postoperatively, no losses of lines of CDVA were observed. Postoperative spherical equivalent was within ± 1.00 D in ten eyes (90.9 %). With regard to aberrations, no statistically significant changes were found in higher order and primary coma RMS postoperatively (p ≥ 0.21), and only minimal but statistically significant negativization of primary spherical aberration (p = 0.02) was observed. No severe complications were observed. LASIK surgery using the solid-state laser technology seems to be a useful procedure for the correction of low to moderate hyperopia, with minimal induction of higher order aberrations.

Affirmed: Jury verdict in favor of compounding pharmacy

Trials are supposed to be free from surprises that put one party unexpectedly at an advantage over another party. A period of "discovery" prior to trial allows for each party to learn of all facts in the case, and there is a continuing duty to update discovery as new facts become apparent. In a recent pharmacy malpractice case, the Supreme Court of Iowa held that that the trial judge had appropriately handled a newly discovered fact, and the jury's verdict in favor of the pharmacy was upheld. A patient underwent LASIK surgery to correct her vision. After the surgery, she was diagnosed with postoperative corneal scarring, for which her ophthalmologist recommended corneal scraping followed by the application of mitomycin-C (MMC). The patient's surgery was scheduled for March 9, 2006. The ophthalmologist ordered MMC in a 0.02% concentration from the defendant, the pharmacy. The order was received on March 7. A pharmacist compounded the medication on the morning of March 9, and the medication was placed in a bottle. Records from the surgery indicate that it began at about noon on that day and was completed within an hour. The ophthalmologist applied a substance from a bottle believed to have contained the MMC ordered from the pharmacy. He did not apply the entire contents of the bottle and he placed the remaining contents in a refrigerator in his office. On March 13, the patient returned complaining that her vision had worsened and she had severe headaches. The ophthalmologist determined that the cornea was not healing, and the patient was referred to a teaching hospital where an examining physician concluded that her condition was likely caused by the application of MMC in excess of the 0.02% concentration. Testing the remaining contents in the bottle revealed no trace of MMC. The patient sued the ophthalmologist and the pharmacy. The patient eventually dismissed the ophthalmologist from the lawsuit and proceeded with litigation against the pharmacy only. A period of discovery ensued, ending with a pretrial conference on February 12, 2010. A few days following the pretrial conference, the pharmacy manager discovered new documents indicating that the medication in dispute was never delivered to the ophthalmologist's office, but instead was picked up by the office manager on the afternoon of March 9, 2006, after the time the surgical records indicated the procedure had been completed. Although a delivery log showed a delivery to the clinic that morning, the signature of the person signing for delivery was crossed out, meaning that the delivery had not taken place. A dispensing log from the pharmacy indicated that the MMC medication had been picked up at 1:39 pm on March 9, 2009, and a cash register receipt verified this information. The pharmacy manager provided these new documents to the pharmacy's attorney. At trial, the pharmacy's attorney offered these new documents as evidence. The patient's attorney objected, and the judge ordered a continuance during which the patient's attorney deposed the pharmacy personnel who had knowledge of the documents. The documents were then entered into evidence. The case went to the jury, which returned a verdict for the pharmacy. The patient's attorney contended, on appeal, that the new documents should have been excluded from the evidence presented to the jury. The Supreme Court of Iowa disagreed, noting that the continuance offered by the trial judge gave the attorney "the opportunity to overcome the surprise she confronted at trial." This was considered by the Supreme Court to be a "reasonable course of action." The court noted further that the patient's attorney "did not subsequently request any further relief from the trial court based on a claim that the continuance was inadequate." The court ruled that "a litigant cannot sit on a claim of error until the trial is over and make the claim once the result of the trial is unsatisfactory." The judgment of the trial court, dismissing the case against the pharmacy, was affirmed. Attorneys are responsible for making effective legal arguments based on the facts of a case, and parties to litigation are responsible for providing complete and accurate facts to their attorneys. When a pharmacy discovers new documents or other facts during preparation for trial, the pharmacy's attorneys should immediately be informed, as was done in this case. It is the responsibility of the judge to ensure that appropriate steps are taken to avoid any surprise these documents or other facts may create for opposing counsel. Based on: Whitley v C. R. Pharmacy Service, Inc., 2012 Iowa Sup. LEXIS 71 (June 29, 2012).