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

Long-term effect of intravitreal triamcinolone in the nonproliferative stage of type II idiopathic parafoveal telangiectasia

PURPOSE: To report the visual outcomes and ocular complications of intravitreal triamcinolone acetonide (IVTA) in the treatment of the nonproliferative stage of type II idiopathic parafoveal telangiectasia (IPT). METHODS: Retrospective, multicenter, uncontrolled interventional case series of 19 eyes of 14 consecutive patients with the nonproliferative stage of IPT that had undergone at least one intravitreal injection of 4 mg of triamcinolone acetonide. Demographic, medical, and ocular data were obtained through chart review. The main outcome measures included best-corrected visual acuity at several timepoints of follow up and ocular complications. RESULTS: At baseline the mean logMAR visual acuity was 0.83 ± 0.41 (Snellen 20/135, range 0.3-2). After an average follow-up of 21.2 months (range 6-44 months), the mean logMAR visual acuity remained essentially unchanged from baseline. At 3 months, the logMAR visual acuity was 0.86 ± 0.44 (Snellen 20/145, P = 0.8378), at 6 months 0.86 ± 0.42 (Snellen 20/145, P = 0.8149), at 12 months 0.87 ± 0.46 (Snellen 20/148, P > 0.9999), at 18 months 0.84 ± 0.35 (Snellen 20/138, P = 0.8385), and at the last follow-up 0.82 ± 0.44 (Snellen 20/132, P = 0.9301). Seven eyes were reinjected once. Ten of 19 eyes (53%) developed cataract (3 eyes underwent phacoemulsification and intraocular lens implantation) and 7 of 19 eyes (37%) had an elevated intraocular pressure, none of which required surgical treatment. CONCLUSION: IVTA does not seem to improve visual acuity in most eyes with the nonproliferative stage of IPT. © The Ophthalmic Communications Society, Inc

Optical coherence tomography characteristics of group 2A idiopathic parafoveal telangiectasis

PURPOSE: To describe the optical coherence tomography (OCT) characteristics of patients with group 2A idiopathic parafoveal telangiectasis (IPFT) and to correlate them with biomicroscopic and fluorescein angiographic (FA) findings based on Gass and Blodi staging classification for group 2A IPFT. METHODS: Fifty-two eyes of 26 consecutive patients with IPFT underwent biomicroscopic fundus examination, color fundus photography, FA, and OCT. Main outcome measures were OCT characteristics and their correlation with biomicroscopy and FA. RESULTS: The most common OCT findings that help differentiate between stages in group 2A IPFT are 1) highly reflective dots in the inner retina that correspond with microvessels seen by FA in Stage 1 (5 eyes [62.5%]); 2) the presence of hyporeflective intraretinal spaces in the absence of retinal thickening and highly reflective dots in the retina in Stage 2 (9 [81.8%] and 10 eyes [90.9%], respectively); 3) in Stage 3, both outer and inner retina exhibit areas of similar high reflectivity. In addition, the retinal pigment epithelium (RPE)/choriocapillaris complex is thickened or disrupted as evidenced by an area of high reflectivity (13 eyes [81.2%]); 4) a highly reflective area nasal or temporal to the fovea in the inner or outer retinal layers in Stage 4 suggesting RPE proliferation and migration (13 eyes [100%]); and 5) a fusiform thickening and duplication of the highly reflective RPE/choriocapillaris complex corresponding to choroidal neovascularization in Stage 5 (4 eyes [100%]). Our OCT characteristics correlated well with biomicroscopic and FA findings for Stages 4 and 5. However, the hyporeflective spaces that are evident on OCT could not be seen clinically at the slit lamp or on FA. In addition, our OCT findings on eyes with group 2A IPFT Stage 3 have not, to our knowledge, been previously described. CONCLUSIONS: Optical coherence tomography findings in group 2A IPFT were characteristic for each stage and may be helpful in making the diagnosis as well as defining the anatomical staging proposed by Gass and Blodi. Optical coherence tomography complements biomicroscopic and FA findings in the evaluation of group 2A IPFT. © The Ophthalmic Communications Society, Inc

Un-explained visual loss following silicone oil removal: Results of the Pan American Collaborative Retina Study (PACORES) Group

Purpose: To report the incidence and clinical features of patients that experienced un-explained visual loss following silicone oil (SO) removal. Methods: Multicenter retrospective study of patients that underwent SO removal during 2000-2012. Visual loss of ≥2 lines was considered significant. Results: A total of 324 eyes of 324 patients underwent SO removal during the study period. Forty two (13%) eyes suffered a significant visual loss following SO removal. Twenty three (7.1%) of these eyes lost vision secondary to known causes. In the remaining 19 (5.9%) eyes, the loss of vision was not explained by any other pathology. Eleven of these 19 patients (57.9%) were male. The mean age of this group was 49.2 ± 16.4 years. Eyes that had an un-explained visual loss had a mean IOP while the eye was filled with SO of 19.6 ± 6.9 mm Hg. The length of time that the eye was filled with SO was 14.8 ± 4.4 months. In comparison, eyes that did not experience visual loss had a mean IOP of 14 ± 7.3 mm Hg (p < 0.0002) and a mean tamponade duration of 9.3 ± 10.9 months (p < 0.0001). Conclusions: An un-explained visual loss after SO removal was observed in 5.9% of eyes. Factors associated with this phenomenon included a higher IOP and longer SO tamponade duration. © The Author(s) 2017

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

Anatomical and functional outcomes of symptomatic idiopathic vitreomacular traction

Purpose: To describe the natural history of eyes with symptomatic idiopathic vitreomacular traction (VMT). Methods: Retrospective multicenter study of 168 eyes with spectral-domain optical coherence tomography (SD-OCT) findings consistent with idiopathic VMT. All eyes were graded according to SD-OCT findings. Grade 1 was defined as incomplete cortical vitreous separation with foveal attachment. Grade 2 was defined as Grade 1 plus intraretinal cysts or clefts. Grade 3 was defined as Grade 2 plus a foveal detachment. All patients were followed for at least 6 months. Results: There were 168 patients (51 men) with a mean age of 68.8 ± 10.7 years. Patients were followed for a mean of 22.7 ± 20.1 months. The mean duration of symptoms before the initial presentation was 3.65 ± 5.42 months. At baseline, 72 eyes had Grade 1, 74 eyes had Grade 2, and 22 eyes had Grade 3 SD-OCT findings. Over the follow-up period, 36 eyes (21.4%) had spontaneous resolution of the VMT with normalization of the foveal anatomy. The mean time to resolution was 12.3 ± 12.6 months. An unfavorable anatomical outcome occurred in 7.7% (13 of 168) of the eyes, with 6 eyes developing a lamellar macular hole and 7 eyes developing a full-thickness macular hole. This occurred at a mean of 10.3 ± 10.7 months after the presentation. Subgroup analysis based on baseline SD-OCT grade showed that 4.1% (3 of 73) of Grade 1 eyes compared with 6.8% (5 of 74) of Grade 2 eyes, and 23.8% (5 of 21) of Grade 3 eyes developed a full-thickness macular hole or lamellar macular hole (P 0.0109, chi-square test). In the remaining 119 eyes, at the last follow-up, 65 eyes had Grade 1, 42 eyes had Grade 2, and 12 eyes had Grade 3 VMT. On average, the best-corrected visual acuity improved from 0.40 ± 0.35 logarithm of the minimum angle of resolution (Snellen, 20/50) at baseline to 0.35 ± 0.36 logarithm of the minimum angle of resolution (Snellen, 20/45; P 0.0372), and the mean central macular thickness improved from 350 ± 132 m to 323 ± 121 m. Conclusion: Spontaneous resolution of VMT occurred in 21.4% (36 of 168) of eyes after a mean follow-up of 11.4 ± 12.6 months. An unfavorable anatomical outcome occurred in 7.7% (13 of 168) of eyes. The baseline SD-OCT grade may predict the progression to full-thickness macular hole

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