Choroidal imaging by spectral domain-optical coherence tomography

AbstractDespite the fact that the choroid plays an important role in the structure and function of the eye, it has not been studied in detail in vivo. Improvements in optical coherence tomography (OCT) imaging technology allow the routine imaging of the choroid and deep optic nerve structures in most patients. As with any new technology, it needs validation in both healthy and diseased eyes. Reproducible measurements of choroidal and lamina cribrosa thickness are possible. Several variables such as age, axial length, and time of day, affect choroidal thickness and must be taken into account when interpreting data on choroidal thickness. Lamina cribrosa thickness appears to be affected by age as well but other factors need to be determined. Choroidal thickness may be used to differentiate between central serous chorioretinopathy (CSC), polypoidal choroidal vasculopathy (PCV) and exudative age-related macular degeneration (AMD). Enhanced depth imaging-optical coherence tomography (EDI-OCT) of the choroid may detect tumors not detectable by ultrasound. Studying the choroid may help us gain insight into the pathogenesis of several diseases such as AMD, CSC, glaucoma, posteriorly located choroidal tumors, and PCV among others

Intravitreal Bevacizumab (Avastin) for Diabetic Retinopathy: The 2010 GLADAOF Lecture

This paper demonstrates multiple benefits of intravitreal bevacizumab (IVB) on diabetic retinopathy (DR) including diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) at 24 months of followup. This is a retrospective multicenter interventional comparative case series of intravitreal injections of 1.25 or 2.5 mg of bevacizumab for DME, PDR without tractional retinal detachment (TRD), and patients who experienced the development or progression of TRD after an intravitreal injection of 1.25 or 2.5 mg of bevacizumab before vitrectomy for the management of PDR. The results indicate that IVB injections may have a beneficial effect on macular thickness and visual acuity (VA) in diffuse DME. Therefore, in the future this new therapy could complement focal/grid laser photocoagulation in DME. In PDR, this new option could be an adjuvant agent to panretina photocoagulation so that more selective therapy may be applied. Finally, TRD in PDR may occur or progress after IVB used as an adjuvant to vitrectomy. Surgery should be performed 4 days after IVB. Most patients had poorly controlled diabetes mellitus associated with elevated HbA1c, insulin administration, PDR refractory to panretinal photocoagulation, and longer time between IVB and vitrectomy

Twelve-Month Follow-Up of Dexamethasone Implants for Macular Edema from Various Diseases in Vitrectomized and Nonvitrectomized Eyes

Purpose. To evaluate the best-corrected visual acuity (BCVA), central retinal thickness (CRT), and the number of dexamethasone implants needed to treat cystoid macular edema (CME) from various etiologies over 12 months in vitrectomized and nonvitrectomized eyes. Methods. This multicenter retrospective cohort study included 112 patients with CME secondary to retinal diseases treated pro re nata (PRN) with a 0.7 mg intravitreal dexamethasone implant for 12 months. The BCVA, CRT, adverse events, safety data, and number of implants were recorded. Results. Vitrectomized and nonvitrectomized eyes received means of three implants and one implant, respectively, over 12 months (P<0.001). The mean BCVA of all patients improved from 0.13 at baseline to 0.33 (P<0.001) 12 months after one (P=0.001), two (P=0.041), and three (P<0.001) implants but not four implants (P=0.068). The mean baseline CRT decreased significantly (P<0.001) from 463 to 254 microns after 12 months with one (P<0.001), two (P=0.002), and three (P=0.001) implants but not with four implants (P=0.114). The anatomic and functional outcomes were not significantly different between vitrectomized and nonvitrectomized eyes. Increased IOP was the most common adverse event (23.2%). Conclusions. Dexamethasone implant administered PRN improved VA and decreased CRT in CME, with possible long-term clinically relevant benefits for treating CME from various etiologies. Vitrectomized eyes needed more implants compared with nonvitrectomized eyes

Curr Opin Ophthalmol

The application of artificial intelligence (AI) technologies in screening and diagnosing retinal diseases may play an important role in telemedicine and has potential to shape modern healthcare ecosystems, including within ophthalmology. In this article, we examine the latest publications relevant to AI in retinal disease and discuss the currently available algorithms. We summarize four key requirements underlining the successful application of AI algorithms in real-world practice: processing massive data; practicability of an AI model in ophthalmology; policy compliance and the regulatory environment; and balancing profit and cost when developing and maintaining AI models. The Vision Academy recognizes the advantages and disadvantages of AI-based technologies and gives insightful recommendations for future directions

Bevacizumab Intravítreo (Avastin®) en Retinopatía Diabética: Resultados del Grupo Panamericano de Estudio Colaborativo de Retina (PACORES)

Resumen El factor de crecimiento vascular endotelial (VEGF) juega un rol protagónico en la patogénesis de la retinopatía diabética. Su inhibición por el Bevacizumab, un anticuerpo monoclonal contra todas las isoformas del VEGF, ha demostrado ser benéfica en el manejo tanto del edema macular diabético (EMD) como de la retinopatía diabética proliferativa (RDP). Nuestro grupo ha previamente demostrado que múltiples inyecciones intravítreas tanto de 1,25 o 2,5 mg de bevacizumab en ojos con EMD resultan en la reducción del edema macular y mejoría en la agudeza visual. No se observó diferencia alguna entre los resultados de los ojos tratados con dosis más bajas o altas del bevacizumab.  Se estudió también el efecto del bevacizumab intravítreos en ojos con RDP. El bevacizumab intravítreo es capaz de inducir regresión de la neovascularización de la retina y disco óptico. Sin embargo, esta regresión no es permanente y la fotocoagulación panretiniana o vitrectomía son necesarias para consolidar el tratamiento. Se debe tener cautela en ojos con RDP avanzada debido a que la rápida involución de las proliferaciones fibrovasculares pueden conllevar al desarrollo o progresión de un desprendimiento de retina fraccional. Por lo tanto al utilizar el bevacizumab intravítreo como adyuvante en la vitrectomía de pacientes diabéticos, la cirugía no debe ser programada más de 4 días después de dicha inyección

Primary Lamellar Macular Holes: To Vit or Not to Vit

There is a wide spectrum of macular conditions that are characterized by an irregular foveal contour caused by a break in the inner fovea. These include full-thickness macular hole (FTMH), foveal pseudocyst, lamellar macular hole (LMH) and macular pseudohole (MPH). Clinical examination of vitreomacular interface disorders is notoriously poor in differentiating these conditions. These conditions were initially described with slit-lamp biomicroscopy, and the main goal was to distinguish an FTMH from the others. The introduction of optical coherence tomography (OCT) has revolutionized our understanding of the foveal microstructural anatomy and has facilitated differentiating these conditions from an FTMH. However, the definitions of the other conditions, particularly LMH, has evolved over the past two decades. Initially the term LMH encompassed a wide spectrum of clinical conditions. As OCT became more widely used and observations became more refined, two different phenotypes of LMH became apparent, raising the question of different pathogenic mechanisms for each phenotype. Tractional and degenerative pathological mechanisms were proposed. Epiretinal membranes (ERMs) associated with each phenotype were identified. Typical ERMs were associated with a tractional mechanism, whereas an epiretinal proliferation was associated with a degenerative mechanism. Epiretinal proliferation represents Müller cell proliferation as a reactive process to retinal injury. These two types of ERM were differentiated by their characteristics on SD-OCT. The latest consensus definitions take into account this phenotypic differentiation and classifies these entities into LMH, MPH and ERM foveoschisis. The initial event in both ERM foveoschisis and LMH is a tractional event that disrupts the Müller cell cone in the foveola or the foveal walls. Depending on the extent of Müller cell disruption, either a LMH or an ERM foveoschisis may develop. Although surgical intervention for LMH remains controversial and no clear guidelines exist for pars plana vitrectomy (PPV), eyes with symptomatic, progressive ERM foveoschisis and LMH may benefit from surgical intervention

Subretinal drusenoid deposits: An update

A wide spectrum of phenotypic manifestations characterizes age-related macular degeneration (AMD). Drusen is considered the hallmark of AMD and is located underneath the retinal pigment epithelium (RPE). In contrast, subretinal drusenoid deposits (SDDs), also known as reticular pseudodrusens, are located in the subretinal space, on top of the RPE. SDDs are poorly detected by clinical examination and color fundus photography. Multimodal imaging is required for their proper diagnosis. SDDs are topographically and functionally related to rods. SDDs cause a deep impairment in retinal sensitivity and dark adaptation. SDDs are dynamic structures that may grow, fuse with each other, or regress over time. An intermediate step in some eyes is the development of an acquired vitelliform lesion. The presence of SDD confers an eye a high risk for the development of late AMD. SDD leads to macular neovascularization, particularly type 3, geographic atrophy, and outer retinal atrophy

Chromovitrectomy: an Update

Adequate visualization and identification of the posterior hyaloid, epiretinal membranes and the internal limiting membrane are of paramount importance in modern vitreoretinal surgery. "Chromovitrectomy" is a term used for describing the vital dyes use in order to stain these transparent tissues and facilitate their manipulation during vitreous surgery. This article reviews the indications, applications and characteristics of vital dyes in vitreoretinal surgery. Various dyes are currently being used in routine clinical procedures, however the ideal staining agent has not yet been found. Any dye which is injected intravitreally has the potential to become toxic. Triamcinolone acetonide is used to highlight the vitreous and is particularly beneficial in determining the attachment of the posterior hyaloid to the underlying retina. Trypan blue stains epiretinal membranes and facilitates their complete removal. Both indocyanine green and brilliant blue G stain the internal limiting membrane properly, however concerns over indocyanine green toxicity have made surgeons switch to brillliant blue G as a safer alternative

Inhibición Combinada del Factor de Necrosis Tumoral (TNF) y Factor de Crecimiento Vascular Endotelial para el Tratamiento del Edema Macular de Variadas Etiologías: Un Estudio Piloto a Corto Plazo

Objetivo: Reportar la respuesta anatómica y de agudeza visual mejor corregida (AVMC) posterior a la combinación del adalimumab intravítreo (Humira) y bevacizumab (Avastin) en pacientes con edema macular de variadas etiologías. Métodos: Serie retrospectiva intervencional de casos. Se revisaron los registros médicos de 5 pacientes consecutivos (7 ojos) con edema macular de variadas etiologías, incluyendo edema macular pseudofáquico, papiloflebitis diabética, oclusión de la vena central de la retina, oclusión de rama venosa retiniana, y degeneración macular relacionada con la edad. Todos los pacientes fueron tratados con al menos una inyección intravítrea de 1,25 mg/0,05 mL de bevacizumab y 2 mg/0,08 mL de adalimumab. A los pacientes se les  cuantificó su AVMC por cartilla del  Estudio del Tratamiento Temprano de la Retinopatía Diabética (EDTRS), examen oftalmológico, tomografía de coherencia óptica (TCO) y angiografía fluoresceínica (AGF) al inicio, y a las visitas en el primer, tercer y sexto mes. Los resultados se basaron en las modificaciones de la AVMC y la TCO. Resultados: La edad media de los pacientes fue de 71,5  ± 9,4 años. La media de inyecciones combinadas de bevacizumab y adalimumab fue de 2,14 por  ojo (rango: 1 a 4 inyecciones) a 6 meses. La AVMC basal mejoró de 1,19 ± 0,6 logaritmo del mínimo ángulo de resolución (logMAR) a 0,94 ± 0,59 logMAR a 6 meses (P < 0,05). Cuatro (57,1%) de los siete ojos ganaron  ≥ 3 líneas ETDRS de AVMC. El espesor macular central (EMC) al inicio por TCO tuvo una media de 416 ± 150 µm, el cual se redujo a una media de 354 ± 205 µm a 6 meses (P < 0,05). No hubo complicaciones oculares o sistémicas. Conclusiones: El tratamiento intravítreo combinado de bevacizumab y adalimumab a dosis de 1,25 mg y 2,0 mg respectivamente impresiona proporcionar mejoría o estabilidad en la AVMC, TCO y AGF en edema macular de variadas etiologías sin complicaciones sistémicas a los 6 meses de seguimiento. A pesar de las limitaciones por el pequeño tamaño de la muestra, corto seguimiento, y la falta de un grupo control, los resultados sugieren una potencial bioactividad relacionada con los favorables resultados anatómicos y visuales

Effectiveness, Safety and Choroidal Changes of a Fovea-Sparing Technique for the Treatment of Chronic Central Serous Chorioretinopathy with Yellow Subthreshold Laser

The aim of this study was to evaluate the effectiveness and safety of a yellow subthreshold laser (STL) for the treatment of chronic central serous chorioretinopathy delivered in a fovea-sparing pattern and to analyze the post-laser changes in the choroidal structure by Swept-Source Optical Coherence Tomography. This study was a prospective case series of 43 eyes corresponding to 37 patients. Data were recorded at 6, 12 and 24 weeks after the STL treatment. The best-corrected visual acuity improved in 93% of the patients and remained stable in 7%. The subretinal fluid was completely reabsorbed in 27.9%, 32.6% and 69.8% of the patients at 6, 12 and 24 weeks, respectively. There were reductions in the choroidal thickness of 13.1% and 25.3% at 12 and 24 weeks, which corresponded to reductions of 17.5% and 45.9% in the choriocapillaris and Sattler layer and reductions of 12.2% and 21.2% in the Haller layer at 12 and 24 weeks, respectively (p &lt; 0.05). This might account for the effect of the laser on the inner choroidal vasculature, the dysregulation of which is believed to be at the core of central serous chorioretinopathy. No laser-related complications were detected. Overall, the fovea-sparing STL was safe and effective in this series of patients