Excimer Laser Refractive Surgery Research Articles

Cornea and Anterior Segment Parameters and Their Importance in Eye Disease

Corneal and anterior segment parameters (ASP) are valuable in diagnosis and risk assessment of diseases such as glaucoma and keratoconus and it is also an invaluable tool in patient selection and surgical planning of excimer laser refractive surgery. Devices where cornea and anterior segment parameters are measured include Sirius system, Pentacam, Orbscan, Galilei, Anterior Segment Optical Coherence Tomography (ASOCT).

Биоптический подход к эксимерлазерной хирургии при сочетанной патологии роговицы и хрусталика

Purpose. To consider a biooptical approach to excimer laser surgery for combined pathology of the cornea and lens. Material and methods. The work is based on 20-year clinical observations of the results of excimer laser refractive, opto-reconstructive and medical surgery in combined pathology of the cornea and lens based on a biooptical approach (more than 1500 operations). Particular emphasis was placed on the cycloplegic functional test and the use of stromal saturation with 0.25% chilled to +5–7 °C isotonic riboflavin solution during photoablation. The studies used modern diagnostic devices OPD-scan, RTVue XR100 and TMS-5 and excimer ophthalmic lasers from various companies. Results. In case of combined refractive pathology of the cornea and lens, the cycloplegic test made it possible to more accurately determine the degree of ametropia, its accommodative component with compensation of corneal astigmatism, and the presence of lens astigmatism. In all cases, the determination of the volume of photorefractive ablation was calculated taking into account the contribution of the cornea and lens to the formation of ametropia and aberrations of the optical system of the eye. The diameter of the optical and transition zone during photorefractive ablation was calculated depending on the state of the pupil diameter in photopic and mesopic conditions. Obtained in the course of studies on the OPD-Scan device, objective information on the difference between the pupil width in mesopic and photopic conditions made it possible to individualize the sizes of the optical and transition zones during photorefractive ablation, to avoid the «Halo» and «Gler» effects. Photoablation with saturation of tecorneal stroma with riboflavin reduced the response of aseptic inflammatory and regenerative reactions, the severity and duration of the corneal syndrome, and provided earlier stabilization of optical refractive indices. Conclusion. When performing excimer laser refractive, opto-reconstructive and therapeutic operations with combined pathology of the cornea and lens, a biooptical approach is required, taking into account the leading role of the cornea and lens in the formation of the optical system of the eye and visual acuity. Keywords: biooptics, photoablation, excimer laser corneal surgery

Excimer Laser Corneal Refractive Surgery in the Clinic: A Systematic Review and Meta-analysis.

Objective To systematically evaluate the efficacy, safety, recovery speed, and long-term visual quality of excimer laser corneal refractive surgery and to provide evidence-based medicine for the promotion and use of excimer laser corneal refractive surgery. Methods Randomized controls on excimer laser refractive surgery in Web of science, PubMed, EMBASE, ScienceDirect, Cochrane Library, China Knowledge Network (CNKI), China VIP Database, Wan Fang Database, and China Biomedical Literature Database (CBM) were searched by the computer. Randomized controlled trial (RCT) data were extracted independently by two researchers, and the risk of bias of each included RCT was assessed according to the Cochrane Handbook 5.1.0 criteria. Meta-analysis of the collected data was performed using RevMan5.4 statistical software. Results In the end, 9 high-quality literatures were included, with a total of 4366 samples, and meta-analysis was used. There was no significant difference in uncorrected visual acuity WMD after excimer laser keratorefractive surgery, but there was a statistically significant difference in WMD in the safety of excimer laser keratorefractive surgery. The results of uncorrected visual acuity (close) indicated the following: Chi2 = 13.56, DF = 5, P = 0.02, and I2 = 100%; the results of uncorrected visual acuity (distance) indicated the following: Chi2 = 34.44, DF =5 (P < 00000), and I2 = 85%; the results of best corrected visual acuity (myopia) indicated the following: Chi2 = 0.65, DF = 3, P = 088 > 0.05, and I2 = 0%; the results of best corrected visual acuity (hyperopia) indicated the following: Chi2 = 1.80, DF = 3, P = 0.61 > 0.05, and I2 = 0%. Conclusion Excimer laser corneal refractive surgery is safe and effective, with faster recovery and better long-term visual acuity treatment effect. However, more studies and follow-up with higher methodological quality and longer intervention time are needed for further validation.

CT Assessment of Vascular Density at Limbus Area after Excimer Laser Refractive Surgery in Myopic Patients

Purpose: to assess the indicators of vascular network density at limbus area in patients with myopia and myopic astigmatism before and after excimer laser refractive surgery.Material and methods. A total of 22 patients aged 18 to 37 years with myopia and myopic astigmatism of varying degrees, who previously underwent excimer laser refractive surgery, were examined. Additionally, the vascular network density at limbus area was assessed quantitatively in the preoperative and early postoperative periods using the Nidek RS-3000 AngioScan OCT device and utilizing a module for scanning the anterior segment of the eye.Results. One hour after excimer laser refraction surgery, there was a decrease in vascular network density at limbus area in all four analyzed sectors (upper, lower, temporal, nasal). One day after surgery, there was an increase in this indicator, tending to preoperative values. We were unable to identify the dependence of the degree of vascular network density on the method of corneal flap formation.Conclusion. OCT-angiography makes it possible to assess the indicators of vascular density at limbus area. The estimated indicators varied depending on the time passed after excimer laser refractive surgery.

Axial length growth difference between eyes after monocular laser refractive surgery: eight patients who underwent myopic laser ablation for both eyes at intervals of several years

BackgroundMyopia is a global public health issue. Controlling myopia progression is a primary focus of myopia studies today. Peripheral retinal myopic defocus is considered the mechanism for reduced myopia progression in orthokeratology studies. The topographic change in the front corneal surface after laser refractive surgery and orthokeratology procedures may appear similar. The purpose of this study was to explore the role of myopic laser ablation on axial length (AL) growth.MethodsMyopic patients who underwent monocular excimer laser refractive surgery first in one eye and then in another eye several years later because of myopia occurrence or myopia progression were recruited. The axial length elongation and refraction (spherical equivalent) between the two eyes were observed and compared.ResultsA total of 8 myopic patients were enrolled in the study. The AL increased from 24.52 ± 0.96 mm to 24.68 ± 1.03 mm but without significance (T = 1.49, P > 0.05) in the ablated eyes. The AL increased significantly from 23.73 ± 0.91 mm to 24.26 ± 0.95 mm in the nonablated eyes (T = 6.76, P < 0.001). The AL elongation of the ablated eyes with 0.16 ± 0.30 mm growth was significantly lower than that of the nonablated eyes with 0.53 ± 0.32 mm growth (T = 8.98, P < 0.001). The spherical equivalent (SE) increased significantly in the ablated eyes (− 0.59 ± 0.21 (D), T = 6.36, P < 0.001) and in the nonablated eyes (− 0.97 ± 0.55 (D), T = 4.91, P < 0.01), and the difference between the two eyes was significant (T = 3.05, P < 0.05).ConclusionsThe inhibitory effect of myopic laser ablation on AL elongation reported in the limited case studies argues for animal research on its efficacy as a new intervention for myopia progression.

Новый взгляд на фотопротекцию и кросслинкинг в эксимерлазерной коррекции зрения

Purpose. To develop approaches to excimer laser keratorefractive surgery based on a new view of the photoprotective function of the cornea, ablation-induced secondary radiation, photoprotective and side effects of crosslinking. Material and methods. The literature data and our own 32-year clinical observations of complications in excimer laser vision correction, methods of their treatment and prevention have been analyzed. Particular emphasis was placed on the analysis of works on photoprotection and crosslinking in photorefractive surgery. New approaches to excimer laser keratorefractive surgery are based on studies on the use of riboflavin for photoprotection and laser-induced crosslinking in corneal ablation (598 operations). Corneal crosslinking was assessed by computed keratotopography, optical coherence tomography, and corneal densitometry. Long-term results were followed up to 8 years. Results. Complications in excimer laser refractive surgery were associated with the development of dry eye syndrome, the formation of subepithelial or intrastromal fibroplasia. Ablation-induced secondary radiation played an important role in the development of complications of excimer laser refractive surgery. It negatively affected keratocytes, nerves and increased oxidative stress in the cornea. To protect against secondary radiation, a new technology of keratoablation with 0.25% isotonic riboflavin solution has been developed. This reduced oxidative stress and aseptic inflammatory response. According to OCT and densitometric studies, a decaying effect of crosslinking with the formation of a membrane structure on the ablation surface was revealed. Local photoprotection during ablation with riboflavin and the effect of crosslinking in combination with postoperative spectacle spectral UV photoprotection accelerated the stabilization of optical-refractive and visual results, increased the photoprotective and strength properties of the thinned cornea. This reduced the risks of keratoectasia and earlier development of cataracts. Conclusion. A new look at photoprotection and crosslinking in excimer laser refractive surgery provides for keratoablation with riboflavin in combination with postoperative spectacle spectral photoprotection from external UV radiation. Key words: excimer laser refractive surgery, dry eye, fibroplasia, keratoectasia, riboflavin, photoprotection, crosslinking.

Thermographic Behavior of the Cornea During Treatment With Two Excimer Laser Platforms.

PurposeTo investigate the temperature of the cornea during treatment with the excimer laser using two platforms, Nidek EC-5000 and Schwind Amaris 750S.MethodsA prospective case series study was conducted in a reference center in Mexico City including patients aged 18 years or older who had any type of ametropia and underwent excimer laser refractive surgery. The patients had measurements of corneal temperature with an infrared camera before, during, and after ablation treatment. Results of prior corneal surface temperature, temperatures during excimer laser surgery, and delta temperature for each platform were analyzed and compared.ResultsA total of 107 eyes were analyzed. Mean baseline temperature was 32.7 ± 1.03°C for the Nidek group and 31.5 ± 1.4°C for the Amaris group. Mean maximum temperature was 39.94 ± 1.3°C for the Nidek group and 35.6 ± 1.5 °C for the Amaris group. Delta temperature was higher in the Nidek group than in the Amaris group. There were statistically significant associations between treated micrometers, treated diopters, and time in the Nidek group and no such associations in the Amaris group.ConclusionsThe different excimer laser devices used and the variety in the optical design, together with different software ablation algorithms, resulted in different levels of thermal loading; peak temperature rose in all measurements. Eyes treated with Nidek reached temperatures that doubled those found with Amaris.Translational RelevanceThe correlation between Delta of temperature with defocus, depth, and treatment time is different regarding excimer laser generation.

Oral Aminoacids Supplementation Improves Corneal Reinnervation After Photorefractive Keratectomy: A Confocal-Based Investigation.

Aim of this retrospective study was to estimate the effect of oral supplementation with amino acids (AA) on corneal nerves regrowth after excimer laser refractive surgery with photorefractive keratectomy (PRK). Based on the pre and post-surgical treatment received, 40 patients with 12 months of follow-up were distributed in two groups: 20 patients had received oral AA supplementation 7 days before and 30 days after PRK, and 20 patients without AA supplementation, as untreated reference control. All patients followed the same standard post-operative topical therapy consisting of an association of antibiotic and steroid plus sodium hyaluronate during the first week, then steroid alone progressively decreasing during 30 days and sodium hyaluronate for the following 3 months. In vivo corneal confocal microscopy was used to evaluate the presence of sub-basal corneal nerve fibers during 12 months after PRK. Results have shown that sub-basal nerves regenerated significantly faster (p <0.05), and nerve fibers density was significantly higher (p <0.05) with a more regular pattern in the eyes of AA treated patients with respect to the untreated control group. Therefore, our data indicate that oral supplementation with AA improved significantly corneal nerve restoration after PRK and could thus be considered as an additional treatment during corneal surgical procedures.

For adults with refractive errors, what are the effects of wavefront excimer laser refractive surgery?

For adults with refractive errors, what are the effects of wavefront excimer laser refractive surgery?

Photorefractive surgery with excimer laser and its impact on the diagnosis and follow-up of glaucoma. A review

Excimer laser refractive surgery is a procedure performed worldwide to solve refractive errors and reduce dependence on glasses or contact lenses. There has been an increase in the number of procedures performed around the world. Myopia is the most common indication for corneal photorefractive surgery. Myopic patients have a higher risk of developing some type of glaucoma in their lifetime, such as primary open-angle glaucoma and others. Refractive surgery ablates central corneal stromal tissue, altering its thickness and biomechanics, which in turn makes it difficult to accurately measure intraocular pressure (IOP), since it underestimates it. This underestimation of IOP may delay the diagnosis of de novo glaucoma in patients with a history of refractive surgery. Each patient who wishes to undergo corneal refractive surgery should undergo a thorough glaucoma examination in order to monitor and detect the possible development and / or progression of glaucoma. A very useful practical approach is to perform a series of IOP measurements before and after surgery, when the eye is already stable, and the difference between the averages of the two sets of readings can then be used as a personalised correction factor for postoperative IOP monitoring in that eye. Also, if there is any suspicion of a possible glaucoma, paraclinical tests, such as coherent optical tomography of the retinal nerve fibre layer (RNFL), visual fields and photos of the optic nerve should be requested. All this data prior to refractive surgery should be provided to these patients, so that they can save it and give it to their treating ophthalmologists in the future.

PHOTOREFRACTIVE SURGERY WITH EXCIMER LASER AND ITS IMPACT ON THE DIAGNOSIS AND FOLLOW-UP OF GLAUCOMA. A REVIEW.

Excimer laser refractive surgery is a procedure performed worldwide to solve refractive errors and reduce dependence on glasses or contact lenses. There has been an increase in the number of procedures performed around the world. Myopia is the most common indication for corneal photorefractive surgery. Myopic patients have a higher risk of developing some type of glaucoma in their lifetime, such as primary open-angle glaucoma and others. Refractive surgery ablates central corneal stromal tissue, altering its thickness and biomechanics, which in turn makes it difficult to accurately measure intraocular pressure (IOP), since it underestimates it. This underestimation of IOP may delay the diagnosis of de novo glaucoma in patients with a history of refractive surgery. Each patient who wishes to undergo corneal refractive surgery should undergo a thorough glaucoma examination in order to monitor and detect the possible development and / or progression of glaucoma. A very useful practical approach is to perform a series of IOP measurements before and after surgery, when the eye is already stable, and the difference between the averages of the two sets of readings can then be used as a personalised correction factor for postoperative IOP monitoring in that eye. Also, if there is any suspicion of a possible glaucoma, paraclinical tests, such as coherent optical tomography of the retinal nerve fibre layer (RNFL), visual fields and photos of the optic nerve should be requested. All this data prior to refractive surgery should be provided to these patients, so that they can save it and give it to their treating ophthalmologists in the future.

Исследование биомеханических свойств роговицы на приборе CORVIS ST (Oculus, Германия) у пациентов с миопией и миопическим астигматизмом

Purpose. To evaluate the corneal biomechanical properties using the CORVIS ST device (Oculus, Germany) in patients with myopia and myopic astigmatism with intact cornea as well as in patients with myopia and myopic astigmatism who underwent excimer laser refractive surgery using femtolaser or microkeratome. Material and methods. Totally the study included 65 patients aged 18 years to 56 years with myopia and myopic astigmatism of various degrees were examined. They were scheduled for excimer laser refractive surgery after laser refractive surgery in different periods from 5 days to 5 years. Among the additional methods of examination, all patients were measured the biomechanical properties of the cornea using a CORVIS ST device (Oculus, Germany). Results. After excimer laser refractive surgery performing for myopia and myopic astigmatism correction, indicators of the corneal biomechanical properties, namely indicators describing stiffness and elasticity were changed, as well as IOP indicators. Conclusion. The biomechanical properties of the cornea, such as stiffness and elasticity, can be assessed using the CORVIS ST device (Oculus, Germany). After excimer laser vision correction of myopia and myopic astigmatism, corneal stiffness and elasticity decreases. IOP value in patients after excimer laser correction of myopia and myopic astigmatism decreases. It is associated with a decrease in corneal thickness but is not associated with a true decrease in IOP. Key words: biomechanical properties of the cornea, refractive surgery, excimer laser vision correction, femtolaser vision correction, myopia, myopic astigmatism.

Wavefront excimer laser refractive surgery for adults with refractive errors.

Wavefront excimer laser refractive surgery for adults with refractive errors.

Comparison of the Trend of Excimer laser refractive surgery in Provinces of Iran between 2010 and 2014

Purpose. The aim of the present study was to compare the trend of excimer laser refractive surgery in different provinces of Iran. Methods. This cross-sectional study was performed in 12 provinces of Iran in 2015 using the data of 2010 to 2014. A total of 28 surgical centers were selected. For each center, one week per season was randomly selected, giving a total of 20 weeks for all seasons of the study years. Then, to estimate the surgical rate in the selected provinces, since 4 weeks were selected each year, the number of operations on the 4 weeks was multiplied by 12.5 to generalize the results to 50 weeks (= 1 year). After applying the weight of each center, the number of refractive operations on each year was divided by the population of the province on that year, and reported per million population. Results. On average, Kermanshah (35.8%, P<0.001) and Tehran (3.1%, P<0.001) had the highest and lowest annual increase and Qom (11.8%, P<0.001) had the highest annual decrease in the rate of excimer laser refractive surgery, respectively. The highest rate was seen in Tehran in 2012 (8885 operations per million population) and the lowest rate was seen in Gilan in 2010 (142 operations per million population). Moreover, the concentration index was 0.25 in 2012, indicating a socioeconomic inequality in the rate of excimer laser refractive surgery. Conclusion. The results of the present study showed an increasing trend in the rate of the excimer laser refractive surgery in 9 Iranian provinces for the first time. Moreover, concerning the inequalities and the higher surgical rate in provinces with a better economic status, it is necessary to expand an insurance coverage and equip more public centers with the instruments and devices required for laser refractive surgery.

Prevalence of laser refractive surgery among ophthalmologists in Saudi Arabia

PurposeThe primary aims of this study are to assess the prevalence of excimer laser refractive surgery among ophthalmologists in Saudi Arabia, evaluates the satisfaction rates among ophthalmologists who have undergone laser refractive surgery and whether they would recommend the procedure to their immediate family members. MethodsA cross-sectional study surveyed ophthalmologist irrespective of specialty or subspecialty in Saudi Arabia. A self-reported survey tool has been used for data collection. Candidates were contacted by email and WhatsApp messages that introduced the nature of the study and an online link to a survey was included. For those who did not respond to the digital contact, direct survey interviews were conducted at an Ophthalmology conference in Riyadh, Saudi Arabia, 2018. ResultsThe final study sample was comprised of 183 ophthalmologists. Most of them 107 (58%) reported that they currently are performing laser refractive surgery.There were 73 (39.89%) ophthalmologist who self-reported that they are emmetropic, 110 (60.11%) self-reported themselves as ametropic, not including presbyopia.Of the 110 ophthalmologists with refractive errors, 52 (47.27%) were candidate for laser refractive surgery for myopia, hyperopia or astigmatism. Most of non- candidates attributed the non-candidacy to non- specific reasons and dry eye. Of the 52 participants who reported themselves as candidates for laser refractive surgery, 20 (38.46%) reported that they had undergone laser refractive surgery, and 32 (61.54%) had not. Most of them (50%) reported that they “like to wear glasses or contact lenses. In general, 14 (70%) reported complete satisfaction with the postoperative outcome.Of all ophthalmologists participated in the study, 94% would advise laser refractive surgery to their first-degree relatives. ConclusionExcimer laser vision correction among ophthalmologists in Saudi is much higher than the market penetration in the general population reported in other countries. Most of the ophthalmologists who underwent the procedure were satisfied with the outcome.

Prevalence of laser refractive surgery among ophthalmologists in Saudi Arabia.

PURPOSE:The primary aims of this study are to assess the prevalence of excimer laser refractive surgery among ophthalmologists in Saudi Arabia, evaluates the satisfaction rates among ophthalmologists who have undergone laser refractive surgery and whether they would recommend the procedure to their immediate family members.METHODS:A cross-sectional study surveyed ophthalmologist irrespective of specialty or subspecialty in Saudi Arabia. A self-reported survey tool has been used for data collection. Candidates were contacted by email and WhatsApp messages that introduced the nature of the study and an online link to a survey was included. For those who did not respond to the digital contact, direct survey interviews were conducted at an Ophthalmology conference in Riyadh, Saudi Arabia, 2018.RESULTS:The final study sample was comprised of 183 ophthalmologists. Most of them 107 (58%) reported that they currently are performing laser refractive surgery.There were 73 (39.89%) ophthalmologist who self-reported that they are emmetropic, 110 (60.11%) self-reported themselves as ametropic, not including presbyopia.Of the 110 ophthalmologists with refractive errors, 52 (47.27%) were candidate for laser refractive surgery for myopia, hyperopia or astigmatism. Most of non- candidates attributed the non-candidacy to non- specific reasons and dry eye. Of the 52 participants who reported themselves as candidates for laser refractive surgery, 20 (38.46%) reported that they had undergone laser refractive surgery, and 32 (61.54%) had not. Most of them (50%) reported that they “like to wear glasses or contact lenses. In general, 14 (70%) reported complete satisfaction with the postoperative outcome.Of all ophthalmologists participated in the study, 94% would advise laser refractive surgery to their first-degree relatives.CONCLUSION:Excimer laser vision correction among ophthalmologists in Saudi is much higher than the market penetration in the general population reported in other countries. Most of the ophthalmologists who underwent the procedure were satisfied with the outcome.

Laser vision correction among Kuzbass miners

Background. In the structure of Kuzbass miners ophthalmopathology, disorders of refraction and accommodation occupy the first place. Excimer laser vision correction is the only acceptable method for correcting various refractive errors that allows miners engaged in the underground coal mining to remain in their profession and continue their career.&#x0D; Objective. To assess the long-term results of excimer laser refractive surgery in miners to evaluate this method as a means of vocational rehabilitation.&#x0D; Material and methods. A survey was conducted in the main group including 135 Kuzbass miners who underwent excimer laser vision correction for professional reasons. The comparison group consisted of 135 patients of various professions unrelated to coal mining who met the general selection criteria. All the patients underwent an extended range of ophthalmologic examinations.&#x0D; Results. The visus in both eyes in the comparison group was 1.2 (1.01.2), in the group of miners 1.0 (0.91.2), p0.05. The values of the sphere and cylinder in the groups are mainly in the range of residual myopia. The clinically significant correlation of the index of contrast sensitivity was established with the visual acuity, age of patients, the period after the operation, and underground experience in the group of miners. In the group of miners, OCT-detected changes are twice as common as they are in the control group, and peculiarities of the anterior segment are 1.5 times more frequent, according to biomicroscopy.&#x0D; Conclusion. The obtained clinical and functional results of excimer laser operations enable professional rehabilitation of miners engaged in the underground work, and provide a high level of occupational safety.

Determinación del poder corneal con un tomógrafo corneal luego de cirugía refractiva con láser excimer

Introducción. La determinación del poder corneal, después de la cirugía refractiva con láser excimer, es difícil. Diferentes alternativas con el uso de tomógrafos corneales se han utilizado para esta medición. Objetivo. Evaluar diversos métodos de determinación del poder corneal en pacientes operados de cirugía fotorrefractiva, incluyendo pruebas diagnósticas con medidas cuantitativas. Metodología. Estudio retrospectivo de pacientes operados de cirugía fotorrefractiva que tuvieran resultados refractivos y tomografía corneal post-operatoria al menos diez semanas luego de cirugía. Resultados. En los ojos miopes se encontraron diferencias significativas en el valor determinado por la queratometría derivada de la historia clínica al compararla con la queratometría manual promedio postoperatoria, la queratometría simulada y el Mean Pupil Power del tomógrafo Sirius®. Por otra parte, al promediar la queratometría manual promedio postoperatoria con el Mean Pupil Power postoperatorio (valor denominado Kpop promedio 1) y compararla con la queratometría derivada por el método de la historia clínica, no se observaron en los pacientes miopes diferencias estadísticamente significativas. Asimismo, al promediar la queratometría simulada postoperatoria del equipo Sirius® con el Mean Pupil Power postoperatorio (valor denominado Kpop promedio 2) y compararla con la queratometría derivada por el método de la historia clínica tampoco se observaron en los pacientes miopes diferencias estadísticamente significativas. Por otro lado, en los ojos hipermétropes y con astigmatismo mixto, los promedios de los errores del Mean Pupil Power postoperatorio, con respecto a la queratometría derivada por el método de la historia clínica, no fueron significativamente diferentes de los errores al comparar la Kpop promedio 1 y la Kpop promedio 2 con la queratometría derivada por el método de la historia clínica. Conclusiones. En ojos miopes las determinaciones del poder corneal postoperatorio con las Kpop promedio 1 y Kpop promedio 2 se aproximan más a la queratometría derivada por el método de la historia clínica que a las mediciones de la queratometría manual promedio postoperatoria, la queratometría simulada postoperatoria o el Mean Pupil Power del equipo Sirius®. [Jaramillo LC, Galvis V, Tello A, Camacho PA, Castillo A, Pareja LA. Determinación del poder corneal con un tomógrafo corneal luego de cirugía refractiva con láser excimer. MedUNAB. 2018;21(1):16-30. doi:1029375/01237047.2397].

The Characteristics of Excimer Laser Refractive Surgery Candidates.

To determine the demographic and refractive characteristics of excimer laser refractive surgery candidates in Iran. This was a cross-sectional study between 2010 and 2014. All information was collected from 28 centers randomly selected from 12 provinces. Then, for each season of the year, one week was chosen through simple random selection, and within each week, 3 days were again chosen randomly. All excimer laser surgical procedures performed during these 3 days were identified by training staff, and data were extracted from patient charts. A total of 14,569 charts were reviewed; 67.5% of the subjects were female and the rest were male. Of the total surgeries, 18.6% had been done in 2010 which reached to 19.1% in 2014. The mean age of people receiving refractive surgery showed an upward trend (P<0.001) and female patients were significantly younger than male patients (P<0.001). The 25 to 39 years age group received the highest number of surgeries (31.9% of the total) and there was a significant association with gender (P<0.001). The most common refractive error was compound myopic astigmatism with a prevalence of 79.3%. In 2010, 33.3% of the performed surgeries were covered by insurance policies, and this decreased to 30.2% in 2014 (P<0.001). Women with compound myopic astigmatism in the age range of 25 and 35 years are the most frequent users of excimer laser refractive surgery. Less than one-third of laser refractive surgeries are covered by insurance policies. Therefore, proper planning for improving services to this group must be given priority.

Регресс эффекта после эксимерлазерных рефракционных операций

Регресс эффекта после эксимерлазерных рефракционных операций