Refractive Surgery Patients Research Articles

Percent tissue altered and corneal ectasia.

This article reviews the association of a novel metric, percentage tissue altered (PTA), with the occurrence of ectasia after laser in-situ keratomileusis in eyes with normal corneal topography, and analyses the influence of the variables that comprise it, and its role on eyes with suspicious topography. PTA is derived from [PTA = (FT + AD)/CCT] where FT = flap thickness, AD = ablation depth, and CCT = preoperative central corneal thickness. Our studies revealed that there is a robust relationship between high PTA and ectasia risk in eyes with normal preoperative topography. PTA higher or equal to 40% presented the highest odds ratio and highest predictive capabilities for ectasia risk than each of the variables that comprise it, residual stromal bed or age. Average thicker flaps alone were insufficient to create ectasia unless coupled with greater ablation depths, meaning a high PTA. In eyes with suspicious topography, even low PTA value is sufficient to induce ectasia. This new metric, PTA, should be taken into account when screening patients for refractive surgery. Patients with normal topography or tomography, presenting a PTA higher or equal to 40% should be considered at higher risk for post laser in-situ keratomileusis ectasia.

LASIK y ablación de superficie en pacientes tratados con amiodarona

ObjectiveTo determine the anatomical and functional outcomes of corneal refractive surgery in patients on amiodarone, a drug listed as being contraindicated in patients undergoing this procedure. Material and methodsA retrospective observational study was conducted on all consecutive patients who took amiodarone and who underwent LASIK or surface ablation from January 2003 to December 2014. Functional (visual and refractive) outcomes are described. ResultsA total of 20 patients (33 eyes) were included. No significant intraoperative or postoperative complications were found. ConclusionsIn our experience, LASIK and surface ablation did not produce significant clinical complications in selected patients taking amiodarone. The absolute exclusion of certain systemic medications should be reconsidered.

Application of corneal tomography before keratorefractive procedure for laser vision correction.

Ectasia after refractive surgery represents a major concern among refractive surgeons. Corneal abnormalities and preexisting corneal ectasia are the most important risk factors. Corneal topography and central corneal thickness are the factors traditionally screening for in refractive surgery candidates. Study of the anterior surface by Placido topography allows for identification of keratoconus before biomicroscopy. However, this is insufficient for the evaluation of pre-operative refractive surgery. There are cases of ectasia after laser in situ keratomilusis (LASIK) without identifiable risk factors such that there is a need to go beyond the corneal surface. A key requirement is quantifying susceptibility to corneal biomechanical instability and progression to ectasia. Tomographic indices derived from elevation maps and pachymetry spatial variation produce a Belin Ambrosio display final D index (BAD-D index), which has shown better results compared to surface curvature indices for detecting very mild forms of ectasia. A logistic regression formula, integrating age, residual stromal bed, and BAD-D (Ectasia Susceptibility Score, ESS) resulted in a significant improvement in accuracy, leading to 100% sensitivity and 94% specificity for detecting susceptible cases. A comprehensive corneal structural analysis based on corneal segmental tomography can detect susceptible corneas, which increases safety for refractive surgery patients.

Corneal Epithelial Thickness Measured by Manual Electronic Caliper Spectral Domain Optical Coherence Tomography: Distributions and Demographic Correlations in Preoperative Refractive Surgery Patients.

The aim of this study was to report the distributions and demographic correlations of corneal epithelial thickness measured by manual electronic caliper spectral domain optical coherence tomography in preoperative refractive surgery patients. This was a retrospective review. The charts of 218 consecutive patients (413 eyes) who presented for refractive surgery evaluation from April 2013 through September 2013 were retrospectively reviewed. The mean corneal epithelial thickness was 51.0 μm with a range of 43 to 61 μm. Corneal epithelial thickness was significantly correlated with sex (P < 0.0001), corneal keratometry (P = 0.01), and underlying corneal thickness excluding the epithelium (P = 0.0268). No significant associations were identified in which corneal epithelial thickness correlated with either age (P = 0.0760) or existing refractive status of the eye (P = 0.5135). Corneal epithelial thickness measured by manual electronic caliper optical coherence tomography in preoperative refractive surgery patients is comparable with the findings for the general population using other measurement techniques, the awareness of which may be useful in the preoperative assessment of these patients.

Cataract surgery outcomes in corneal refractive surgery eyes: Study from the European Registry of Quality Outcomes for Cataract and Refractive Surgery

To analyze visual outcomes after cataract surgery in patients with previous corneal refractive surgery. Cataract surgery clinics in 18 European countries and Australia. Database study. Cases of cataract extraction with corneal refractive surgery eyes (corneal refractive cases) were identified from all cataract extractions reported to the European Registry of Quality Outcomes for Cataract and Refractive Surgery database over a 5-year period. Preoperative and postoperative measurements and trends over time were analyzed. Of 807,220 cataract extractions, 1229 (0.15%) were corneal refractive cases. There was a significant increase, over time, in the number of corneal refractive cases (P < .001). Corneal refractive patients were younger than patients without corneal refractive surgery (nonrefractive patients) (62.9 years versus 74.0 years; P < .001) but had similar mean preoperative and postoperative corrected-distance visual acuity (CDVA) (preoperative logMAR 0.44[6/16] for both [P = .286]; postoperative logMAR 0.06[6/7] for both [P = .245]). Postoperative CDVA was worse than preoperative CDVA in 35 (4%) corneal refractive and 8,999 (1.5%) nonrefractive patients (P < .001). In all, 74 (8.5%) of 873 corneal refractive versus 16,566 (2.8%) /584,496 nonrefractive patients, having cataract surgery, had preoperative CDVA of logMAR 0.0[6/6] or better (P < .001). Nineteen (54.3%) of 35 corneal refractive case patients who had worse postoperative CDVA had preoperative CDVA of logMAR 0.0(6/6) or better. Cataract surgery has been reported with increasing frequency in corneal refractive surgery patients, since 2008. These patients had preoperative CDVA similar to those of patients without previous corneal refractive surgery but were younger and were at higher risk of worse postoperative CDVA, especially if they had preoperative CDVA of logMAR 0.0(6/6) or better. No author has any financial or proprietary interest in any material, or method, mentioned.

Advances in scleral lenses for refractive surgery complications.

The last two decades have brought advances in materials and manufacturing of large diameter rigid gas-permeable contact lenses, and a greater appreciation of the role of scleral lenses for therapeutic indications. The purpose of this review is to provide an update on the use of rigid gas-permeable scleral lenses in the management of patients with complications after refractive surgery. There are recent reports on clinical experience with specific scleral lens designs from single institutions in cohorts that include patients who have undergone refractive surgery. Typically, these are patients with 'irregular corneas' after radial keratotomy or LASER assisted in-situ keratomileusis, but patients with keratectasia, dry eye syndrome, and corneal neuralgia are also reported. Visual outcomes and wearing success rates are high in these reports, although outcomes for refractive surgery patients are not reported separately. Clinicians who encounter patients with complications after corneal refractive surgery should be aware of advances in scleral lenses. Scleral lenses are an alternative to surgical intervention in patients who might otherwise be considered poor contact lens candidates.

Evaluation of Objective Visual Acuity Measured by the Double-Pass Technique in Corneal Refractive Surgery Patients

Evaluation of Objective Visual Acuity Measured by the Double-Pass Technique in Corneal Refractive Surgery Patients

Topographic and biomechanical evaluation of corneas in patients with ocular rosacea.

To compare the topographic and biomechanical properties of corneas in the eyes of patients with ocular rosacea (OR) with those of healthy individuals. Thirty-four healthy individuals (control group) and 34 patients with OR (study group) were evaluated in this study. Topographic measurements including keratometry values, irregularity, and surface asymmetry index in the right eye of each participant were obtained using a Scheimpflug camera with a Placido disc topographer (Sirius). Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOP), and Goldmann-related IOP were measured using the Reichert Ocular Response Analyzer. Central corneal thickness was also measured using ultrasonic pachymetry and the Sirius corneal topography system. Topographic parameters were not significantly different between the groups (P > 0.05). Mean CH and CRF were significantly lower in patients with OR (P = 0.003 and 0.001, respectively). Central corneal thickness was significantly lower in patients with OR compared with healthy controls (P < 0.001). Mean Goldmann-related IOP and corneal-compensated IOP were not significantly different between the groups (P = 0.09 and 0.13, respectively). This study demonstrated that although the eyes of patients with OR had corneal topographic findings similar to those of healthy controls, corneal biomechanical measurements (CH and CRF) were significantly lower in patients with OR. These results need to be considered when planning corneal refractive surgery in patients with OR.

Corneal biomechanics in steroid induced ocular hypertension.

This study aims to investigate the corneal biomechanical properties of steroid sensitive refractive surgery patients and to compare these with those patients that did not have steroid induced ocular hypertension after refractive surgery. This retrospective study in a tertiary care center involved 48 eyes with steroid induced ocular hypertension (Group I) and 61 eyes of age and sex matched refractive patients who used topical steroids for the same duration as group I without developing ocular hypertension (group II). All patients had preoperative ophthalmological examination, pachymetry and postoperative corneal hysteresis (CH) and resistance factor (CRF) measurements by ocular response analyser. The preoperative CH and CRF measurements of the two groups were compared. The mean CH was statistically lower in group I (6.89±1.62) as compared to group II (7.80±1.30) (p=0.001). The CRF was higher in group I (7.68±2.26) as compared to group II (7.66±1.72) but the difference was not statistically significant (p=0.96). The preoperative spherical refractive error (r=0.43, p=0.00) and postoperative corneal thickness (r=0.58, p=0.001) were moderately correlated with CH. A statistically significant decrease in CH in subjects with steroid induced ocular hypertension is found. Previous studies have revealed an association of low CH with risk of glaucomatous damage of optic nerve. This may imply risk of optic disc damage in this ocular hypertension group if not recognized and treated properly. However the results should be confirmed with larger sample sizes.

Comparison of objective and subjective refractive surgery screening parameters between regular and high-resolution Scheimpflug imaging devices

To compare objective and subjective metrics from regular and high-resolution Scheimpflug devices (Pentacam) to determine their equivalence and interchangeability for refractive surgery screening. Emory Vision at Emory University, Atlanta, Georgia, USA. Retrospective comparative case series. Eyes of consecutive screened refractive surgery patients were evaluated with high-resolution and regular Scheimpflug devices. Objective parameters evaluated included keratometry (K) values, central corneal thickness (CCT), and device-generated keratoconus screening indices. Masked expert reviewers subjectively graded images as normal, suspicious, or abnormal. One hundred eyes of 50 patients were evaluated. The mean K values were not significantly different (anterior K: high resolution 1.21 diopters [D] ± 1.13 (SD) versus regular 1.15 ± 1.16 D, P = 0.73; posterior K: 0.34 ± 0.23 D versus regular 0.35 ± 0.23 D, P = .67). The mean CCT was significantly thinner in the high-resolution group (514.7 ± 26.6 μm versus 527.6 ± 27.6 μm (P < .0001) with limits of agreement of -12.9 to +17.5 μm. Most keratoconus screening indices were more suspicious with the high-resolution device than with the regular device except the indices of height asymmetry and height deviation. Subjectively, 60% of cases received the same score, high resolution was more suspicious in 28% of cases, and regular was more suspicious in 12% of cases; there was only slight subjective agreement between technologies (κ = 0.26 to 0.31). Regular and high-resolution Scheimpflug imaging devices generated different objective values and significantly different subjective interpretations with poor inter-reviewer agreement. The high-resolution device provided a more conservative overall output. For refractive surgical screening, the 2 devices are not interchangeable. Proprietary or commercial disclosures are listed after the references.

Screening of refractive surgery candidates for LASIK and PRK.

The aim of this study was to evaluate exclusion criteria in screening patients for refractive surgery. Patients screened for initial refractive surgery by a single surgeon at the Cole Eye Institute (Cleveland Clinic) between 2007 and 2012 were reviewed. Exclusion criteria for patients who were not offered refractive surgery based on history and/or examination parameters were analyzed. A total of 1067 refractive candidates were enrolled in the study. Five hundred nineteen (48.6%) were male and 548 (51.4%) were female with a mean age of 39 ± 12 (range, 17-78) years. Refractive surgery was performed in 657 (61.6%) patients, and photorefractive keratectomy was considered the best option for 106 (9.9%) patients. Four hundred ten (38.4%) of all screened patients did not have refractive surgery, and 134 of these patients (12.6%) were considered to have contraindications for laser in situ keratomileusis and photorefractive keratectomy. Among the excluded patients, 69 (51.5%) were male and 65 (48.5%) were female with a mean age of 40 ± 14 (range, 18-78) years. Abnormal corneal topography (34.3%) and low or insufficient corneal thickness (23.1%) were the most common reasons for exclusion. High myopia (10.5%) and (insipient or definite) cataract (9.7%) were also common reasons for exclusion. Other common factors for exclusion were high hyperopia (3.7%), need to wear reading glasses after surgery (3.7%), and severe dry eye unresponsive to treatment (3.7%). Abnormal corneal topography and low, or insufficient, corneal thickness remain the most common exclusion factors for corneal refractive surgery. Factors such as cataract, too high of correction, and severe dry eye are also common reasons for exclusion of patients.

Hyperopic corneal refractive surgery in patients with accommodative esotropia and amblyopia

To explore whether hyperopic excimer corneal refractive surgery can affect ocular alignment and stereopsis in patients with both accommodative esotropia and amblyopia. In this prospective study, 26 eyes of 13 patients with accommodative esotropia and amblyopia underwent bilateral hyperopic corneal refractive surgery: 9 patients underwent laser in situ keratomileusis (LASIK); 4, laser epithelial keratomileusis (LASEK). The main ocular examinations included pre- and postoperative best-corrected and uncorrected visual acuity, refractive error, ocular alignment, and stereopsis. Preoperative cycloplegic refraction in the right eyes was +5.64 ± 2.09 D; in the left eyes, +5.91 ± 1.97 D. After surgery, refraction in the right eyes was +1.13 ± 1.21 D; in the left eyes, +1.44 ±1.53 D. The mean logMAR uncorrected visual acuity was 0.46 ± 0.30 before surgery and 0.32 ± 0.25 after surgery (t = 5.72, P = 0.001). The mean pre- and postoperative best-corrected visual acuity were 0.31 ± 0.28 and 0.29 ± 0.25, respectively; there was no significant difference between the two groups (t = 1.23, P = 0.22). The average uncorrected esotropia was 37.92(Δ) ± 9.12(Δ) before surgery and 2.76(Δ) ± 2.80(Δ) after (P<0.001). Using a synoptophore, 2 patients (15.3%) had preoperative stereopsis and 11 patients (84.6%) had postoperative stereopsis. No patients experienced lower stereopsis postoperatively. In this cohort, hyperopic corneal refractive surgery can improve the alignment, uncorrected visual acuity, and stereopsis in patients with accommodative esotropia and amblyopia.

Data extraction and reporting strategies of studies assessing non-central corneal thickness by Pentacam: a review.

To review data extraction strategies for the reporting of non-central corneal thickness with the Pentacam system. Using predefined search terms, the electronic National Institutes of Health database (PubMed) was searched for studies assessing non-central corneal thickness using the Pentacam instrument. The article titles of the search results were screened for relevance. The abstracts of papers with appropriate titles were retrieved and read. Articles with relevant abstracts were obtained and read in full. The reference list of each article was hand searched to identify further studies. Articles reporting central corneal thickness only were excluded. Seventeen peer-reviewed studies were identified. Considerable differences in data extraction and reporting of non-central corneal thickness were noted, with non-central pachymetry being assessed at locations between 1.5 and 5.0mm away from the centre. The terminology used to describe non-central pachymetry was inconsistent. Ring-averaged and single point pachymetry data have been reported. Ring-averaged pachymetry may obscure considerable regional variability in corneal thickness. The use of different data extraction and reporting strategies can obscure regional corneal thickness asymmetries. This may influence the monitoring of corneal crosslinking outcomes, the interpretation of corneal swelling in contact lens studies and the clinical decision-making in preoperative assessments of refractive surgery patients. For the reliable identification of regional corneal thickness variations point-pachymetry data appears to be preferable over ring-averaged pachymetry.

Factors affecting the decision for refractive surgery in patients with high degrees of ametropia

To evaluate reasons referred patients do not have refractive surgery. University Eye Clinic, Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark. Cross-sectional study. The case records of patients referred for refractive surgery from January 2011 to December 2012 were examined for explanatory reasons. Data measured at the clinical preexamination of those who did and those who did not have refractive surgery were compared. A logistic regression model was used to assess the measured data's influence on the decision to have or not have refractive surgery. Of the 2150 patients whose records were reviewed, 939 (43.7%) refrained from having refractive surgery. The most common reason was a change of mind (40.7%) followed by low central corneal thickness (CCT) (12.6%) and unstable refraction (10.8%). The 939 patients who refrained from surgery had significantly higher astigmatism and lower intraocular pressure, CCT, and corrected distance visual acuity than the patients who had surgery. The patients who changed their minds were not significantly different in any parameter from the patients who had refractive surgery. Using an outcome threshold of 0.5, the logistic regression model classified 63.04% of the patients correctly. Reasons for refraining from refractive surgery were numerous, with a change of mind after the preexamination being the most common. Patients who changed their minds were very similar to those who had surgery, indicating that personal factors were important determinants. No author has a financial or proprietary interest in any material or method mentioned.

Topical cyclosporine a treatment in corneal refractive surgery and patients with dry eye.

To evaluate preoperative and postoperative dry eye and the effect of cyclosporine A treatment in patients screened for corneal refractive surgery and treated with photorefractive keratectomy (PRK) or LASIK. A consecutive case series of 1,056 patients screened for corneal refractive surgery from 2007 to 2012 was retrospectively analyzed. The level of preoperative and postoperative dry eye and the responsiveness to topical cyclosporine A treatment were assessed. One eye of each patient was randomly selected. A total of 642 eyes progressed to surgery: 524 (81.6%) and 118 (18.4%) underwent LASIK and PRK, respectively. Of 81 (7.7%) diagnosed as having dry eye, 55 were deemed potential candidates and optimized for refractive surgery. Thirty-seven patients with moderate dry eye were treated with topical cyclosporine A prior to surgery (mean duration: 3.2 ± 2.1 months; range: 1 to 12 months). After cyclosporine A treatment, 28 (75.7%) eyes underwent LASIK, 4 (10.8%) eyes underwent PRK, and 5 (13.5%) eyes were not operated on due to failed treatment of dry eye. Postoperative refractive surgery-induced neurotrophic epitheliopathy (LINE in LASIK) was noted in 132 (27.3%) and 12 (11.1%) eyes that underwent LASIK and PRK, respectively. Topical cyclosporine A was prescribed in 79 LASIK-induced and 3 PRK-induced dry eyes. After 12 months or more of cyclosporine A treatment, 5 (6.1%) eyes continued to have dry eye symptoms or signs. Topical cyclosporine A treatment is effective therapy for optimizing patients for refractive surgery and treatment of new onset or worsened dry eye after surgery.

Long-Term Tracking of the Central Corneal Endothelial Mosaic

PurposeWhen comparing follow-up endothelial cell (EC) density measurements it is only possible to demonstrate cell loss in large cohorts or in pronounced cases due to the standard deviation of measurements. However, especially in clinical studies or refractive surgery patients, EC stability is an important factor. Thus we developed a computer program to achieve cell-by-cell alignment of conventional specular non-contact EC photographs. This is a pilot study to evaluate whether this new diagnostic technique is applicable in postoperative patients.MethodsDigitized endothelial cell photos of 30 eyes following implantation of a phakic posterior chamber intraocular lens for correction of high myopia were analyzed. All EC centroids were dotted on each image, and early and late follow-up pictures were automatically aligned on the basis of these centroids. The tracking results were confirmed via alternating image presentation of the corresponding image areas, and were reviewed for loss of individual cells. In addition, conventional EC density measurements were performed.ResultsMean time interval between first and second postoperative EC image was 1.4 years (range 3 months – 2.2 years), with early images taken at a median of 5.5 months after IOL implantation (lower/upper quartile 1.2–12.3 months). Extrapolated central EC density was 2812±500/mm2 at the first time point, and 2797±524/mm2 at the second time point. In 26 out of 30 image pairs, the EC mosaic was successfully retraced; cell loss in this area was excluded via photo flickering. Only in 4 image pairs, the EC mosaic could not be matched.ConclusionsWe demonstrate that the corneal EC mosaic of clinical routine non-contact microscope pictures can be superimposed and compared on single cell level over time with our new computer based program. This new method is valuable to judge on EC stability even in small cohorts since it does not require mean values and standard deviations.

Diadenosine polyphosphates after laser in situ keratomileusis and photorefractive keratectomy refractive techniques

To study the concentrations of diadenosine polyphosphates in the ocular surface after PRK and LASIK. Sixty-one patients (30 males and 31 females) with ages ranging from 20 to 63 (34.04 ± 9.13 years) were recruited in Balear Institute of Ophthalmology, Palma de Mallorca, Spain. LASIK was performed in 92 eyes of 46 patients and PRK in 25 eyes of 15 patients. Variations in the levels of diadenosine polyphosphate (Ap4 A and Ap5 A), Schirmer I (Jones test), TBUT, corneal staining together with the Dry Eye Questionnaire to evaluate discomfort and dryness were studied. All tests were performed at the preoperative visit and at 1-day, 2-week, 1-month and 3-month postoperative visits. Ap4 A showed a 5 and 3.5 fold increase at the 1-day visit for LASIK and PRK, respectively. LASIK patients continued having higher statistically significant concentrations (p = 0.01) all over the follow-up. Ap5 A showed no significant differences at any visit. Tear volume decreased during the 3 months in LASIK. The PRK cases had a normal volume at 1 month. TBUT in LASIK increased at the 1-day visit (p = 0,002) and decreased from the 2 weeks onwards and for the PRK, decreased by a 35% at the 1-day visit and kept reduced for a month. Discomfort only increased at the 1-day visit (p = 0.007). Dryness frequency was similar in all visits. Ap4 A levels only are increased in refractive surgery patients during the first day after the surgery. This increasing suggests that Ap4 A may help accelerating the healing process.

Topical administration of Oftaquix® and Tobrex® in refractive surgery

Background: Due to the growing resistance of causative microorganisms to previous generations of antibiotics and to the risk of post-op infectious complications associated with it, an efficacy and safety assessment of modern fluoroquinolones’ prophylactic topical administration appears to be reasonable. Purpose: To investigate the efficacy and safety of levofloxacin 0.5 % ophthalmic solution (Oftaquix®, Santen, Finland) topical use in modern excimer laser refractive surgery (LASIK). Material and methods: Patients were randomized into two treatment groups: Thirty two patients (64 eyes) were treated with levofloxacin 0.5 % ophthalmic solution (Oftaquix®, Santen, Finland) b.i.d. and thirty patients (60 eyes) received tobramycine 0.3 % eye drops (Tobrex®, Alcon-Couvreur, Belgium) q. t.d., both during first 7 days post-op. LASIK procedure using excimer laser MEL-80 (Carl Zeiss Meditec, Germany) and mechanical microkeratome LSK Moria Evolution-2 (Moria, France) was performed in all patients for myopia from –1.0 to –12.0 D. Patient’s age varied from 18 to 40 years (mean age 28.4±7.8). Results: During topical application of Oftaquix® and Tobrex® in our refractive surgery patients there were no topical, or systemic adverse reactions, or allergic reactions. Oftaquix® and Tobrex® had good topical tolerability. Therapeutic dosage regimen, sufficient in terms of anti-infective prophylaxis, in case of Oftaquix® was twice as low in comparison to Tobrex®. Tear film break-up time (TFBUT) preand post-op was comparable between groups. In both groups, TFBUT post-op was significantly lower compared to pre-op values (p 0.01). Tear production (Shirmer-I test) in both groups remained almost the same (p 0.05). Conclusion: Oftaquix® (Santen, Finland) ophthalmic solution is effective and safe for prevention of infectious complications after LASIK and appears to be a rational alternative to tobramycine 0.3 % eye drops (Tobrex®, Alcon-Couvreur, Belgium).

시력교정수술환자의 병원선택요인과 만족도

The study compared refractive surgery patients` hospital selection factors and satisfaction, through this to see the factors influencing patients` satisfaction, aiming at 235 patients visiting two Eye hospitals. The research results are followed. First, target group`s hospital selection factors appeared facilities and environment factor, reliability factor, personal service factor, and accessibility factor in the order. Second, patients` satisfaction appeared reliability factor, facilities and environment factor, and personal factor in the order. Fourth, in the result comparing patients` expectation on hospital selection and satisfaction score, all factors of facilities and environment, personal service, and reliability had high satisfaction score than expectation. Third, in the result of factors influencing refractive surgery patients` satisfaction, in surgery determination period, surgery expenditure, and hospital selection factors among characteristics relating to refractive surgery, facilities and environment, personal service, and reliability appeared as satisfaction influencing factors. In conclusion, the study found that hospital selection factors and satisfaction influencing factors by refractive surgery patients` surgery type are considered to be able to be used to establish marketing strategy in the fields excluded from insurance application, the researches to improve patients` satisfaction in patient-oriented medical market should be continuously proceeded.

Longitudinal change of refraction over at least 5 years in 15,000 patients

To report the natural, longitudinal history of shifts in refractive errors in different age groups in a large western European cohort over at least 5 years in the same patients. The electronic database of a large regional clinic containing 225,000 patients was searched for records of patients with a follow-up of at least 5 years, excluding all patients who had received any surgical interventions in any eye. This search retrieved 15,799 patients aged 3 months to 79 years (median 37.8 years) with refractive follow up of at least 5 years (mean 8.8 years) and no surgical interventions. Differences in spherical equivalents (sum of sphere +1/2 cylinder) and cylinder between first and last visit in the same patients in only the right eye were calculated, and used as the measure of refractive shift. Subsequently differences in change between the right and left eye were also determined. Refractions were found to be mostly stable from 25 to 39 years (n = 3,155 right eyes), with 50% of these patients not changing their refraction. In patients aged 20-24 (n = 825 right eyes), only 39% of the refractions remained stable, whereas 49% experienced a myopic shift. In the age group 40-69 years (n = 6,694), 40-45% remained stable, with an increase in hyperopic shifts. Eighty-five percent of all patients had bilateral symmetric shifts, and 61% showed stable cylindrical values. This report documents clinical relevant changes in spherical equivalents in all age groups within 5 to 10 years in the largest examined European cohort. Refractive surgery patients in particular should be selected accordingly, and be informed about the physiological changes which might still occur during their lifetime.