Severe epithelial ingrowth after pars plana vitrectomy ten years after LASIK relifting.

Epithelial ingrowth is one of the most significant complications of Laser in Situ Keratomileusis (LASIK) refractive surgery. We present the case of a 72-year-old male with a history of myopic LASIK (1999), who underwent cataract surgery and a second thin LASIK sub-Bowman flap to correct refractive error. Then, three months after pars plana vitrectomy for an epiretinal membrane, the patient complained of progressive vision loss. A diffuse haze of the corneal stroma that did not exist before surgery was observed. As the main suspicion was epithelial ingrowth, the flap was lifted and meticulous de-epithelialization of the stromal bed was performed. Mitomycin C 0.02% was applied, the flap was sutured with 10-0 Nylon, and a bandage contact lens was placed. The epithelialization of the interface after vitrectomy in a patient with LASIK could occur even when it is a rare complication and without obvious flap traumatism.

Evaluación del músculo ciliar y del grosor escleral anterior en miopes altos mediante tomografía de coherencia óptica / Assessment of the ciliary muscle and scleral anterior thickness in high myopia by optical coherence tomography

Propósito: Evaluar las dimensiones del músculo ciliar (MC) y del grosor escleral anterior (AST) in vivo en miopes altos mediante tomografía de coherencia óptica de fuente de barrido (SS-OCT) y comparar con sujetos emétropes e hipermétropes.MétodosEstudio transversal en el que se incluyeron 34 miopes altos (≥−6dioptrías [D]), 90 emétropes (−1 a +1D) y 38 hipermétropes (≥+3,5D). Se midieron el grosor del MC (CMT) y el AST en los cuadrantes temporal y nasal a 1, 2 y 3mm del espolón escleral utilizando la SS-OCT. Además, se evaluó la longitud del MC (CML).ResultadosLas dimensiones tanto del CML como del CMT en cualquiera de sus puntos de medida fueron mayores en miopes altos y en emétropes que en hipermétropes, tanto en el cuadrante nasal como en el temporal (p<0,001). Sin embargo, no existieron diferencias entre miopes magnos y emétropes para ninguno de los parámetros (p≥0,076), salvo para el CMT a 3mm en temporal (p<0,001). No existieron diferencias en el AST entre miopes altos, emétropes e hipermétropes, en ninguno de los puntos de medida ni cuadrantes estudiados (p>0,05).ConclusionesLa SS-OCT permite medir el MC in vivo, no observándose diferencias en sus dimensiones entre miopes altos y emétropes, pero sí que fueron menores en hipermétropes. En la medida de la esclera anterior no se observaron diferencias entre los tres grupos analizados según la refracción. (AU)

Purpose: To assess ciliary muscle (CM) and anterior scleral thickness (AST) dimensions in vivo in high myopia using swept-source optical coherence tomography (SS-OCT) and to compare with emmetropic and hyperopic subjects.MethodsCross-sectional study that included 34 high myopic patients (≥−6 diopters [D]), 90 emmetropes (−1 to +1D) and 38 hyperopic patients (≥+3.5D). CM thickness (CMT) and AST were measured in the temporal and nasal quadrants at 1, 2, and 3mm from the scleral spur using SS-OCT. In addition, the length of the CM (CML) was evaluated.ResultsThe dimensions of the CML and the CMT at any of their measurement points were greater in high myopes and emmetropes than in hyperopes, both in the nasal and temporal quadrants (P<.001). However, there were no differences between high myopes and emmetropes for any of the parameters (P≥.076) except for the CMT at 3mm in the temporal quadrant (P<.001). There were no differences in the AST between high myopes, emmetropes and hyperopes, in any of the measurement points or quadrants studied (P>.05).ConclusionsThe SS-OCT allows to measure the CM in vivo, not observing differences in its dimensions between high myopes and emmetropes, but they were smaller in hyperopes. In the measurement of the anterior sclera, no differences were observed between the three groups analyzed according to refraction. (AU)

Assessment of the ciliary muscle and scleral anterior thickness in high myopia by optical coherence tomography.

PURPOSE: To assess ciliary muscle (CM) and anterior scleral thickness (AST) dimensions in vivo in high myopia using swept-source optical coherence tomography (SS-OCT) and to compare with emmetropic and hyperopic subjects. METHODS: Cross-sectional study that included 34 high myopic patients (≥ -6 diopters [D]), 90 emmetropes (-1 to +1 D) and 38 hyperopic patients (≥ +3.5 D). CM thickness (CMT) and AST were measured in the temporal and nasal quadrants at 1, 2, and 3 mm from the scleral spur using SS-OCT. In addition, the length of the CM (CML) was evaluated. RESULTS: The dimensions of the CML and the CMT at any of their measurement points were greater in high myopes and emmetropes than in hyperopes, both in the nasal and temporal quadrants (P < .001). However, there were no differences between high myopes and emmetropes for any of the parameters (P ≥ .076) except for the CMT at 3 mm in the temporal quadrant (P < .001). There were no differences in the AST between high myopes, emmetropes and hyperopes, in any of the measurement points or quadrants studied (P > .05). CONCLUSIONS: The SS-OCT allows to measure the CM in vivo, not observing differences in its dimensions between high myopes and emmetropes, but they were smaller in hyperopes. In the measurement of the anterior sclera, no differences were observed between the three groups analyzed according to refraction.

El glistening de las lentes intraoculares: revisión de la literatura / Glistening on intraocular lenses: a review

El glistening en las lentes intraoculares (LIO) es un fenómeno en el que se forman diminutas microvacuolas llenas de agua dentro del material de la LIO, lo que hace que la luz se disperse y cree un efecto centelleante o reluciente. La presencia del glistening es frecuente en muchos tipos de materiales y modelos de LIO, y se ha estudiado ampliamente en los últimos años para conocer su incidencia, factores de riesgo, evolución y posible relevancia clínica. Clásicamente se ha estudiado in vitro en laboratorio o mediante fotografía obtenida con lámpara de hendidura. Sin embargo, son técnicas que requieren de un explorador experto, además de requerir mucho tiempo y un complejo procesado de las imágenes. En los últimos años, han surgido propuestas basadas en la cámara de Scheimpflug y en la tomografía de coherencia óptica como forma de simplificar el análisis del glistening en las LIO. Se ha descrito que tanto el proceso de fabricación, como el propio material acrílico hidrofóbico, y el tiempo desde la cirugía son factores de riesgo relacionados con la aparición de glistening. Además, aún se desconocen numerosas cuestiones relacionadas con este fenómeno, como la cantidad de puntos o el tamaño de los mismos necesarios para causar afectación de la función visual, ya que se han descrito diferentes fenómenos ópticos relacionados con el glistening de las LIO (AU)

The glistening in intraocular lenses (IOLs) is a phenomenon in which tiny water-filled microvacuoles form within the IOL material, causing light to scatter and create a sparkling or shimmering effect. The presence of glistening is common in many types of IOL materials and models and has been extensively studied in recent years to determine its incidence, risk factors, evolution, and possible clinical relevance. Classically, it has been studied in vitro in the laboratory or by means of photography obtained with a slit lamp, but these were techniques that required either specific technology or an expert explorer, complex image processing, and required a lot of time. In recent years, proposals based on the Scheimpflug camera and optical coherence tomography have emerged to try to simplify the analysis of glistening in IOLs. It has been described that the manufacturing process, the hydrophobic acrylic material, or the time since surgery are risk factors for the appearance of glistening. In addition, many issues related to this phenomenon are still unknown, such as not knowing from what number of points or their size they may have relevance to visual function since different optical phenomena related to glistening have been described on the IOLs (AU)

Evaluación de las modificaciones biométricas del ojo durante la succión del LASIK / Assessment of the biometric modifications of the eye in LASIK during suction

Objetivo Estudiar las modificaciones biométricas del globo ocular durante la succión en la cirugía de queratomileusis in situ asistida por láser (LASIK). Métodos Estudio observacional transversal. Se estudiaron 43 pacientes intervenidos de miopía y astigmatismo miópico. La edad media fue de 38,3 ± 11,5 años, 19 eran mujeres (44,2%). Se realizó una cirugía LASIK convencional con microqueratomo manual. Antes y durante la maniobra de succión se midieron los siguientes parámetros mediante una sonda biométrica de 11 Mhz: profundidad acuosa (AQD), espesor del cristalino (EC), longitud de la cavidad vítrea (LCV) y longitud axial (LA). Se utilizó la prueba t pareada para comparar las medidas biométricas antes y durante la succión. Resultados El equivalente esférico medio fue de -4,5 ± 2,3 dioptrías. Durante la succión, la AQD no aumentó significativamente (p = 0,231). Sin embargo, la LA y LCV aumentaron en 0,12 mm y 0,2 mm, respectivamente (p = 0,039 y < 0,01) y EC disminuyó en 0,20 mm (p < 0,01). La LA aumentó en 42% de los ojos y disminuyó en 16%, mientras que la LCV aumentó en 70% de los ojos y disminuyó en 9%, y el EC se redujo en 67% de los ojos. Conclusiones Las maniobras de succión durante la cirugía LASIK producen cambios de poca magnitud en el globo ocular, principalmente disminución de EC y aumento de LCV y LA. Por lo tanto, es esperable que estas modificaciones produzcan alteraciones anatómicas mínimas (AU)

Purpose To study the biometric modifications of the eyeball during suction in laser assisted in situ keratomileusis (LASIK). Methods Observational and cross-sectional study. We studied 43 patients who underwent surgery for myopia and myopic astigmatism. Mean age was 38.3±11.5 years, and 19 were female (44.2%). Conventional LASIK surgery with a manual microkeratome was performed. Before and during the suction maneuvre the following parameters were measured using an 11 MHz biometric probe: aqueous depth (AQD), lens thickness (LT), vitreous cavity length (VCL) and axial length (AXL). Paired t-test was used to compare the biometric measurements before and during suction. Results The mean spherical equivalent refractive error was −4.5±2.3 diopters. During suction, the AQD did not change significantly (p = 0.231). However, AXL and VCL increased by 0.12 mm and 0.22 mm respectively (p = 0.039 and <0.01) and LT decreased by 0.20 mm (p<0.01). AXL increased in 42% of the eyes and decreased in 16%, VCL increased in 70% of the eyes and decreased in 9%, and the LT was reduced in 67% of the eyes. Conclusions Suction maneuvres during LASIK surgery produce changes of little magnitude in the eye globe, mainly a decrease in LT and an increase in VCL and AXL. Therefore, these modifications are expected to produce minimal anatomic alterations (AU)

Glistening on intraocular lenses: A review.

The glistening in intraocular lenses (IOLs) is a phenomenon in which tiny water-filled microvacuoles (MVs) form within the IOL material, causing light to scatter and create a sparkling or shimmering effect. The presence of glistening is common in many types of IOL materials and models and has been extensively studied in recent years to determine its incidence, risk factors, evolution, and possible clinical relevance. Classically, it has been studied in vitro in the laboratory or by means of photography obtained with a slit lamp, but these were techniques that required either specific technology or an expert explorer, complex image processing, and required a lot of time. In recent years, proposals based on the Scheimpflug camera and optical coherence tomography have emerged to try to simplify the analysis of glistening in IOLs. It has been described that the manufacturing process, the hydrophobic acrylic material, or the time since surgery are risk factors for the appearance of glistening. In addition, many issues related to this phenomenon are still unknown, such as not knowing from what number of points or their size they may have relevance to visual function since different optical phenomena related to glistening have been described on the IOLs.

Assessment of the biometric modifications of the eye in LASIK during suction.

PURPOSE: To study the biometric modifications of the eyeball during suction in Laser assisted in Situ Keratomileusis (LASIK). METHODS: Observational and cross-sectional study. We studied 43 patients who underwent surgery for myopia and myopic astigmatism. Mean age was 38.3 ±â€¯11.5 years, and 19 were female (44.2%). Conventional LASIK surgery with a manual microkeratome was performed. Before and during the suction maneuvre the following parameters were measured using an 11 Mhz biometric probe: aqueous depth (AQD), lens thickness (LT), vitreous cavity length (VCL) and axial length (AXL). Paired t-test was used to compare the biometric measurements before and during suction. RESULTS: The mean spherical equivalent refractive error was -4.5 ±â€¯2.3 diopters. During suction, the AQD did not change significantly (p = 0.231). However, AXL and VCL increased by 0.12 mm and 0.22 mm respectively (p = 0.039 and <0.01) and LT decreased by 0.20 mm (p < 0.01). AXL increased in 42% of the eyes and decreased in 16%, VCL increased in 70% of the eyes and decreased in 9%, and the LT was reduced in 67% of the eyes. CONCLUSIONS: Suction maneuvres during LASIK surgery produce changes of little magnitude in the eye globe, mainly a decrease in LT and an increase in VCL and AXL. Therefore, these modifications are expected to produce minimal anatomic alterations.

Agreement between optical coherence and Scheimpflug tomography: Vault measurements and reproducibility after implantable collamer lens implantation.

PURPOSE: To evaluate the agreement between Scheimpflug tomography (Pentacam, Oculus) and anterior segment optical coherence tomography (AS-OCT, RTVue 100, Optovue) as well as the reproducibility of each technique in assessing the lens-ICL distance (vault) after implantable collamer lens (ICL) implantation. METHODS: The vault was measured manually with Scheimpflug tomography and AS-OCT. Intraclass correlation coefficients (ICC) and Bland-Altman plots were used to determine the reproducibility of measurements and the agreement between them. Multivariate regression analysis was performed to identify predictors of differences in vault measurements between devices. RESULTS: 80 eyes of 46 ICL patients were analyzed. Mean patient age was 33.8±7.4 years (range, 21 to 51), and 27 (59%) were women. The preoperative spherical equivalent refraction ranged from -26 to 8.5 diopters (D). The mean vault measured by AS-OCT was 558.8±240.2µm (range, 162 - 1220) vs. 430.1±215.3µm (range, 0 to 1070) by Pentacam. AS-OCT yielded vault values, on average, 128.1±64.6µm higher than the Pentacam (range, -22 to 293µm). The ICC values for consistency and absolute agreement were 0.960 and 0.928, respectively. Reproducibility of vault measurements was excellent for both devices (ICC≥0.946). Four parameters-vault, pupil diameter (PD), PD differences between devices, and preoperative spherical equivalent refraction-were significant predictors of differences in vault measurements (adjusted-R2=0.412; P<0.001). CONCLUSIONS: Agreement between AS-OCT and Pentacam for vault measurement was good. Vaults were higher when measured by AS-OCT. These differences are clinically relevant, and therefore these devices cannot be used interchangeably to measure vault.

Assessment of changes in the macula and optic nerve head using optical coherence tomography in patients with attention deficit hyperactivity disorder. / Evaluación de los cambios en la mácula y en el nervio óptico mediante tomografía de coherencia óptica en pacientes con trastorno por déficit de atención e hiperactividad.

INTRODUCTION: To assess if there are any differences in macular and papillary thickness using optical coherence tomography (OCT) in patients with attention deficit hyperactivity disorder (ADHD) compared with a control group, including if there are differences between ADHD patients with and without treatment. METHODS: Prospective observational study including 92 eyes of 46 patients divided into 2 groups: 46 eyes of 23 patients with ADHD, and a control group of 46 eyes of 23 healthy patients. The group of patients with ADHD was subdivided into those on treatment with methylphenidate (n=28) and those not on treatment (n=18). The macular thickness, the ganglion cell complex (GCC), and the retinal nerve fibre layer (RNFL) at the papillary level were measured in 12 sectors. RESULTS: A lower central macular thickness was observed in the ADHD patients than in the controls (257.4±20µm versus 267.5±20µm, P=.013), with no differences observed in the GCC (P=.566), or in the RNFL (P=.095). There were no differences in the patients with ADHD with and without treatment, as regards macular thickness and the GCC (P=.160 and P=.375 respectively), but a lower foveal thickness (P=.018) and RNFL in 5/12 sectors at the papillary level (P=.033) were observed in those without treatment. CONCLUSIONS: A lower macular thickness was observed in patients with ADHD than in controls. In addition, patients with ADHD without treatment had a lower thickness of the fovea and RNFL than those patients on treatment.

Agreement between Fourier-domain and swept-source optical coherence tomography used for optic nerve head measurements.

PURPOSE: To assess the correlation between optic nerve head measurements generated by Fourier-domain (FD) and swept-source (SS) optical coherence tomography (OCT) both in healthy Caucasian subjects and patients with primary open angle glaucoma (POAG). MATERIALS AND METHODS: This was a cross-sectional study of the right eyes of 118 subjects. In each participant, the measurements of disc area, cup to disc ratio (CDR), vertical cup to disc ratio (VCDR), rim area and rim volume were performed consecutively by FD-OCT and then SS-OCT. Participant age, gender and spherical equivalent were also recorded. Agreement between the two devices was assessed through intraclass correlation coefficients (ICC) and Bland-Altman plots. RESULTS: The study sample consisted of 95 healthy eyes and 23 eyes with glaucoma. Mean participant age was 48.6±20.0 years, 54.2% were female, and mean spherical equivalent was -1.6±3.0 diopters. FD-OCT and SS-OCT measurements were respectively: mean disc area 1.79±0.3 vs 1.83±0.3 mm2 (ICC=0.71), mean CDR 0.38±0.2 vs 0.33±0.2 (ICC=0.91), mean VCDR 0.58±0.2 vs 0.52±0.2 (ICC=0.92), mean rim area 1.05±0.4mm2 vs 1.03±0.5mm2 (ICC=0.29), and mean rim volume 0.14±0.11 vs 0.21±0.17mm3 (ICC=0.53). Good agreement between the devices was noted for rim area and rim volume in glaucoma subjects (ICC=0.76 and 0.68 respectively), while weak agreement was observed for these variables in healthy subjects (ICC≤0.50). CONCLUSIONS: The CDR and VCDR measurements provided by FD and SS OCT showed excellent agreement for the overall sample. When the devices were used for rim measurements, agreement was excellent only in the POAG patients.

Update on the usefulness of optical coherence tomography in assessing the iridocorneal angle. / Actualización de la utilidad de la tomografía de coherencia óptica para el estudio del ángulo iridocorneal.

The iridocorneal angle, due to its implications in the physiopathology of aqueous humour drainage, is a fundamental structure of the anterior chamber. Anterior segment optical coherence tomography is a rapid and non-invasive technique that obtains images in vivo. The high resolution allows it to analyse the normal anatomy of the angle, any alterations, and the changes that occur after different therapeutic interventions. Anterior segment optical coherence tomography technology has evolved to provide images that allow the identification and quantification of the angular structures in healthy subjects and in glaucoma patients, and especially the trabecular meshwork and the Schlemm's canal. It also enables the angle width to be quantified, with some objective parameters that have been standardised in recent years, such as the trabecular-iris angle, the angle opening distance, and the trabecular-iris area. This technique has multiple uses in the study of the different mechanisms of angle closure, the evaluation of changes after a laser peripheral iridotomy or iridoplasty after cataract surgery, as well as after the implantation of phakic lenses.