Resultados refractivos y visuales en pacientes operados de miopía con técnicas de superficies / Refractive and visual results in patients operated on for myopia with surface techniques

Objetivo: Comparar los resultados visuales y refractivos pre- y posoperatorios en pacientes miopes operados con técnicas de superficie y perfil de ablación asférico. Métodos: Se realizó un estudio experimental controlado aleatorizado abierto, tipo de equivalencia y no inferioridad, en 160 pacientes (320 ojos). En el estudio se formaron dos grupos: el primero quedó constituido por 80 pacientes (160 ojos), a quienes se les realizó queratectomía fotorrefractiva más mitomicina C, y el segundo fue conformado por 80 pacientes (160 ojos), a quienes se les realizó LASEK más mitomicina C. Resultados: Predominaron en ambos grupos las mujeres con miopía leve y edades entre 21 y 29 años. A los tres meses el grupo queratectomía fotorrefractiva más mitomicina C tenía agudeza visual sin corrección de 0,97 ± 0,09; esfera 0,003 ± 0,21; cilindro -0,09 ± 0,30 y equivalente esférico -0,04 ± 0,23. En el grupo LASEK más mitomicina C, la agudeza visual sin corrección fue de 0,96 ± 0,11; la esfera -0,007 ± 0,24; el cilindro -0,08 ± 0,25 y el equivalente esférico -0,06 ± 0,26. Conclusión: Ambas técnicas quirúrgicas mejoraron significativamente los resultados refractivos y visuales, pero no hubo diferencia entre ellas(AU)

Objective: Compare the pre- and postoperative visual and refractive results in myopic patients operated with surface techniques and aspheric ablation profile. Methods: An open randomized controlled experimental study, equivalence and non-inferiority type was carried out in 160 patients (320 eyes). In the study, two groups were formed: the first group was made up of 80 patients (160 eyes), who underwent Photorefractive keratectomy - mitomycin C, and the second group made up of 80 patients (160 eyes), underwent LASEK - mitomycin C. Results: Women with mild myopia and ages between 21 and 29 years old predominated in both groups. At three months, the Photorefractive keratectomy - mitomycin C group had AVSC 0.97 ± 0.09; sphere 0.003 ± 0.21; cylinder -0.09 ± 0.30 and spherical equivalent -0.04 ± 0, 2. 3. In the Photorefractive keratectomy - mitomycin C group, AVSC 0.96 ± 0.11; sphere -0.007 ± 0.24; cylinder -0.08 ± 0.25 and spherical equivalent -0.06 ± 0.26. Conclusion: Both surgical techniques improved significantly refractive and visual results, but there was no difference between them(AU)

Meta analysis of therapeutic effects of domestic deproteinized calf blood extract eye gel on corneal epithelial repair after laser refractive surgery / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To systemically evaluate the clinical efficacy and safety of domestic deproteinized calf blood extract eye gel for corneal epithelial repair after laser refractive surgery.METHODS:We performed a comprehensive search via Pubmed,Embase,Cochrane Library,VIP Chinese Science and Technology Journal Database,CNKI and Wan Fang Chinese periodical Database for the randomized controlled trials(RCTs) at home and abroad about effects of the domestic deproteinized calf blood extract eye gel for corneal epithelial repair after laser corneal refractive surgery with retrieval time from January 2007 to December 2016.According to the inclusion and exclusion criteria,2 medical researchers independently screened documents,extracted data and evaluated the quality.Review Manager 5.3 software was used for Meta analysis.RESULTS:Seven RCTs involving 1042 eyes,including 523 eyes in the treatment group and 519 eyes in the control group,were selected for this Meta-analysis.The results showed that the clinical efficacy in the treatment group was better than that in the control group (OR=1.81,95％CI:1.39 ～2.35;P＜0.001).And the corneal injury symptom score in the treatment group was superior to that in the control group (WMD=-0.33,95％CI:-0.45 to-0.21;P＜0.001).And the corneal healing time in the treatment group was shorter than that in the control group (WMD=-1.26,95％CI:-1.56 to-0.97;P＜0.001).CONCLUSION:The domestic deproteinized calf blood extract eye gel can relieve the patients' symptoms after laser refractive surgery,improve the corneal epithelial recovery and the efficiency of treatment.Due to the limited quality and quantity of the studies these conclusions should be further validated by more welldesigned randomized double blind controlled trials.

Management of Complication after Hyperopic Laser-assisted in-situ Keratomileusis

PURPOSE: We present a case of a patient who underwent corneal refractive surgery to improve their corrected visual acuity due to a complication of hyperopic laser-assisted in-situ keratomileusis (LASIK). CASE SUMMARY: The patient complained of decreased vision after hyperopic LASIK surgery 12 years prior. The corrected distance visual acuity (CDVA) was 20/200 in the right eye and 20/32 in the left, with manifested refractions of +1.25 +2.00 × 90 and -0.25 +2.00 × 80, respectively. The patient had a with-the-rule astigmatism. The values of corneal and total spherical aberration, which can be determined as coefficients of the Zernike polynomials, were respectively -1.027 µm and -0.773 µm in the right eye and -0.965 µm and -0.881 µm in the left eye. Slit lamp biomicroscopy revealed no remarkable findings. We performed surface ablation surgery to flatten the central cornea of the patient's right eye. At 12 months after surgery, the CDVA of the patient's right eye was 20/30 and the negative corneal spherical aberration was reduced. CONCLUSIONS: Corneal refractive surgery to reduce negative corneal spherical aberration by flattening the central cornea is one of possible treatment options for the reduced corrected distance visual acuity after hyperopic LASIK.

New Modified Equation of Contact Lens Method in Determining Post Myopic Laser Refractive Surgery Corneal Power

The purpose of this study was to derive a modified equation for contact lens method (CLM) in calculating post myopic laser refractive surgery corneal power. Methods: A total of 93 subjects who underwent myopic laser refractive surgery at IIUM Eye Specialist Clinic were recruited. The accuracy of postoperative corneal power using the standard CLM and newly-derived contact lens modified method (CLMmod) were compared to the standard comparison method ; the historical method (HM). The CLMmod equation was derived by adjusting postoperative corneal power of CLM according to amount of refractive change. Results: The mean postoperative corneal power using standard CLM was significantly higher than HM (mean difference: -0.24 D, p < 0.001). Fifty seven percent (n = 53 eyes) of the standard CLM results were within ±0.50 D of HM results. The difference between postoperative corneal power using standard CLM and HM increased significantly with the amount of refractive change (r = 0.835; p < 0.001). The mean postoperative corneal power of CLMmod showed that there was no statistical significant difference compared to the HM results (mean difference: 0.00 D, p= 0.964). Eighty eight percent (n = 82 eyes) of the CLMmod results were within ±0.50 D of HM results with improvement of 31% from the standard CLM results. Conclusion: The CLMmod equation provides more accurate calculation in determining post myopic laser refractive surgery corneal power. In near future, this modified equation can be used as an alternative equation to calculate postoperative corneal power when the preoperative data is unavailable.

Selección del paciente para cirugía refractiva: actualización / Update on the selection of patients for refractive surgery

Se realiza una búsqueda de la literatura más actualizada de los últimos cinco años enfocada en publicaciones de expertos y basada principalmente en una revisión realizada recientemente en la revista Current Opinion in Ophthalmology por un grupo de investigadores de la Universidad de Baltimore, Maryland (EE.UU.) sobre las contraindicaciones actuales de la cirugía refractiva. La Academia Americana de Oftalmología publica periódicamente directrices de patrones de práctica para la cirugía refractiva láser. El propósito de esta revisión es proporcionar una actualización sobre las contraindicaciones actuales y los detalles específicos relacionados con la cirugía refractiva láser(AU)

The present paper made a search for the most updated literature in the last five years, focused on expert publications and based on a recent review appeared in Current Opinion in Ophthalmology Journal by a group of researchers from the University of Baltimore in Maryland, United States of America on the current counter indications of the refractive surgery. The American Academy of Ophthalmology systematically publishes the practical guidelines for laser refractive surgery. The objective of this review was to provide update on the current counter indications and the specific details of the laser refractive surgery(AU)

Laser Refractive Surgery Using an Active Eye-Tracking System in Congenital Nystagmus

PURPOSE: Nystagmus is not considered a good indication for laser refractive surgery. However, we report 2 cases with congenital nystagmus that underwent a safe procedure due to improvement of laser firing rate and eye tracker. CASE SUMMARY: Two myopic patients with congenital nystagmus underwent transepithelial photorefractive keratectomy with the Schwind Amaris laser platform using an eye tracker. The laser ablations were performed under topical anesthesia without any mechanical eyeball fixation. A 30-year-old man with a history of muscle surgery at 11 years of age had a conjugate, 4 Hz right beating jerk nystagmus. His preoperative refractive error was -8.50 D sph = -0.50 D cyl x 160degrees x 20/30) in the right eye, and -6.00 D sph = -0.75 D cyl x 30degrees x 20/25) in the left eye. A 19-year-old man had a conjugate, 3 Hz pendular nystagmus. His refractive error was -5.25 D sph = -2.50 cyl x 175degrees x 20/30) in the right eye, and -4.25 D sph = -2.50 D cyl x 180degrees x 20/30) in the left eye. Both patients underwent a well-centered laser ablation without any problems. Six months after surgery, uncorrected visual acuity was 20/25 or better, and refractive error was within +/-0.50 D in all 4 eyes. In addition, the 19-year-old man showed decreased nystagmus amplitude. CONCLUSIONS: In some patients with congenital nystagmus, laser refractive surgery may be safely and accurately performed under topical anesthesia using an active tracking system. The best uncorrected visual acuity may improve in certain patients postoperatively.

Estudio queratométrico por pentacam en hipermétropes con cirugía láser vs. método de maloney / Keratometric study of hypermetropic patients with laser surgery by using pentacam vs. maloney method

OBJETIVO: comparar las queratometrías obtenidas por el Pentacam en ojos hipermétropes operados por láser y las obtenidas a través del Método de Maloney, en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer", desde marzo a mayo de 2013. MÉTODOS: se realizó un estudio prospectivo en 50 ojos de 27 pacientes hipermétropes operados de LASIK, donde se calculó la queratometría promedio mediante el método de Maloney y se comparó con los valores brindados por el Pentacam: valor queratométrico total central y Equivalent K- Reading power de los mapas a color, así como el True Net Power (queratométrico total a 3,0 mm) y las lecturas queratométricas a distintos diámetros del programa Holladay Report. Se comparó la queratometría preoperatoria media de la historia clínica y la estimada aportada por el Pentacam. El análisis estadístico se realizó con la prueba T para datos pareados, utilizando una significación del 95 %. RESULTADOs: no hubo diferencias estadísticamente significativas entre las queratometrías del método de Maloney, el Equivalent K-reading Power y las lecturas de queratometría efectivas a diferentes diámetros. La de 4,5 mm mostró la menor diferencia. El resto de las mediciones difirieron de forma significativa. No se encontró diferencias entre las queratometrías preoperatorias. CONCLUSIONES: el Pentacam aporta poderes corneales que no difieren estadísticamente de los obtenidos por el método de Maloney en ojos hipermétropes con LASIK previo.

OBJECTIVE: to compare the keratometries given by the Pentacam in hyperopic patients operated on with laser and those obtained through Maloney method in "Ramón Pando Ferrer" Cuban Institute of Ophthalmology from March to May of 2013. METHODS: a prospective study was conducted in 50 eyes from 27 hyperopic patients operated on with LASIK, in which average keratometry was estimated using Maloney method and then compared with those of Pentacam system; the used variables were total central keratometric value and Equivalent K-reading Power of color maps, as well as the true net power (total keratometic value at 3,0 mm) and the readings of equivalent keratometry at different diameter of HolladayReport programs. The average preoperative keratometries of the medical histories and those of the Pentacam system were also compared. The statistical analysis included paired T test, using a 95 % significance level. RESULTS: there were not significant statistical differences among the keratometries by Maloney method, the Equivalent K-reading power and the readings of equivalent keratometries at different diameters, being that of 4,5 mm the more accurate. The rest of the measurements differed in a significant way. There were differences among the preoperative keratometries. CONCLUSION: the Pentacam system provides corneal powers that did not statistically differ from those obtained by the Maloney method in hyperopic eyes with prior LASIK.

Long-Term Quality of Life after Myopic Laser Refractive Surgery

PURPOSE: To investigate long-term satisfaction and quality of life after myopic laser refractive surgery. METHODS: This study included 231 myopic patients who underwent laser refractive surgery (LASIK, LASEK or PRK) at least five years prior, between 2002 and 2005, at 5 hospitals. Using a telephone survey, patients were asked to subjectively answer 26 questions regarding satisfaction, quality of life changes, and visual symptoms. RESULTS: The mean patient satisfaction score was 8.12 (scale of 1 to 10). Improvement in quality of life was reported by 91% of the subjects. Intention to have surgery again was reported by 87.9% of the subjects and intention to recommend refractive surgery to a friend or family was reported by 80.5% of the subjects. The most common discomfort symptoms after myopic laser refractive surgery were dry eye symptoms (57.1%), followed by night vision disturbances (54.3%). CONCLUSIONS: Long-term satisfaction and quality of life were shown to be positive in patients treated with myopic refractive surgery.

Comparison between Anterior Corneal Aberration and Ocular Aberration in Laser Refractive Surgery

PURPOSE: To compare changes of anterior corneal aberration (Pentacam(R)) and ocular aberration (aberrometer, LADARWave(R)) after laser refractive surgery. METHODS: Sixty-six eyes underwent laser refractive surgery and were retrospectively reviewed. Anterior corneal aberration and ocular aberration were measured by Pentacam(R) and an aberrometer (LADARWave(R)) respectively. Changes of root mean square (RMS) values of coma, spherical aberration, and total high order aberration (HOA) were evaluated before, 1 month, and 3 months after surgery RESULTS: Ocular aberrations displayed low preoperative values, but after laser refractive surgery, anterior corneal aberration and ocular aberration increased equally. There were no statistically significant differences of internal optics aberration values (ocular aberration minus anterior corneal aberration) in coma, spherical aberration, and total HOA. Anterior corneal aberration and ocular aberration showed statistically significant correlations at 1 and 3 months after surgery. CONCLUSIONS: Internal optics aberration compensated the anterior corneal aberration effectively before surgery, but the increase of anterior corneal aberration after laser refractive surgery exceeded the compensation of internal optics. As a result, anterior corneal aberration and ocular aberration increased equally. The correlation between anterior corneal aberration and ocular aberration after surgery was statistically significant due to the increased proportion of anterior corneal aberration in ocular aberration.