En-face optical coherence tomography in the diagnosis and management of age-related macular degeneration and polypoidal choroidal vasculopathy

Optical coherence tomography (OCT) is a noninvasive imaging modality providing high-resolution images of the central retina that has completely transformed the field of ophthalmology. While traditional OCT has produced longitudinal cross-sectional images, advancements in data processing have led to the development of en-face OCT, which produces transverse images of retinal and choroidal layers at any specified depth. This offers additional benefit on top of longitudinal cross-sections because it provides an extensive overview of pathological structures in a single image. The aim of this review was to discuss the utility of en-face OCT in the diagnosis and management of age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV). En-face imaging of the inner segment/outer segment junction of retinal photoreceptors has been shown to be a useful indicator of visual acuity and a predictor of the extent of progression of geographic atrophy. En-face OCT has also enabled high-resolution analysis and quantification of pathological structures such as reticular pseudodrusen (RPD) and choroidal neovascularization, which have the potential to become useful markers for disease monitoring. En-face Doppler OCT enables subtle changes in the choroidal vasculature to be detected in eyes with RPD and AMD, which has significantly advanced our understanding of their pathogenesis. En-face Doppler OCT has also been shown to be useful for detecting the polypoid lesions and branching vascular networks diagnostic of PCV. It may therefore serve as a noninvasive alternative to fluorescein and indocyanine green angiography for the diagnosis of PCV and other forms of the exudative macular disease.     

Choroidal thickness profile in healthy Indian children

Purpose:

The purpose was to study choroidal thickness and its profile based on location in healthy Indian children using enhanced depth spectral-domain-optical coherence tomography (SD-OCT).

Methods:

In this cross-sectional observational study 255 eyes of 136 children with no retinal or choroidal disease were consecutively scanned using enhanced depth SD-OCT. Eyes with any ocular disease or axial length (AXL) >25 mm or < 20 mm were excluded. A single observer measured choroidal thickness from the posterior edge of the retinal pigment epithelium to the choroid/sclera junction at 500-microns intervals up to 2500 microns temporal and nasal to the fovea. Generalized estimating equations were used to evaluate the correlation between choroidal thickness at various locations and age, AXL, gender and spherical equivalent (SEq).

Results:

Mean age of the subjects was 11.9 ± 3.4 years (range: 5–18 years). There were 62 Females and 74 males. The mean AXL was 23.55 ± 0.74 mm. Mean subfoveal choroidal thickness was 312.1 ± 45.40 μm. Choroid was found to be thickest subfoveally, then temporally. Age, AXL and SEq showed a significant correlation with choroidal thickness, whereas gender did not affect choroidal thickness.

Conclusion:

Our study provides a valid normative database of choroidal thickness in healthy Indian children. This database could be useful for further studies evaluating choroidal changes in various chorioretinal disorders. Age and AXL are critical factors, which negatively correlated with choroidal thickness.     

Prospective evaluation of changes in choroidal vascularity index after half-dose photodynamic therapy versus micropulse laser treatment in chronic central serous chorioretinopathy

Graefe's Archive for Clinical and Experimental Ophthalmology - To assess whether treatment of chronic central serous chorioretinopathy (cCSC) with photodynamic therapy (PDT) and high-density...     

Subclinical subretinal fluid detectable only by optical coherence tomography in choroidal naevi—the SON study

BackgroundSubretinal fluid is a risk factor for growth and malignant transformation of choroidal naevi, however it is unclear if this applies to subclinical fluid that is only detectable by optical coherence tomography (OCT). The objective of this study was to determine the prevalence and associations of subclinical but OCT-detectable subretinal fluid over choroidal naevi.MethodsCross-sectional study of 309 consecutive cases of choroidal naevi imaged by OCT between July 2017 to January 2019. Multicentre international study involving ten retinal specialist centres. All patients presenting to retinal specialists had routine clinical examination and OCT imaging. The prevalence of subclinical OCT-detectable subretinal fluid over choroidal naevi and its associations with other features known to predict growth and malignant transformation were noted and analysed.ResultsOf 309 identified consecutive cases, the mean patient age was 65 years, 89.3% of patients were Caucasian and 3.9% were Asian. The prevalence of subclinical but OCT-detectable subretinal fluid associated with choroidal naevi was 11.7% (36/309). Naevi with fluid were associated with larger basal diameters, greater thickness, presence of a halo, orange pigmentation, hyperautofluorescence, and hypodensity on B-scan ultrasonography.Conclusion and relevanceOf choroidal naevi where subretinal fluid is not visible on clinical examination, 11.7% demonstrate subretinal fluid on OCT scans. These naevi more commonly exhibit features known to be associated with growth and transformation to melanoma. The presence of subclinical OCT-detectable fluid over choroidal naevi may assist in their risk stratification.Subject terms: Risk factors, Uveal diseases, Eye manifestations     

Influence of fellow eye on the diagnosis and classification of central serous chorioretinopathy

Graefe's Archive for Clinical and Experimental Ophthalmology - To assess the influence of fellow eye information on diagnosis and classification of central serous chorioretinopathy (CSCR) using...     

Prepapillary vascular loop-a new classification

Background/ObjectivesTo analyze the ophthalmic characteristics of congenital prepapillary vascular loop (PVL) and to propose a new morphologic classification dividing the loops into six types.Subjects/MethodsCollaborative multinational multicentre retrospective study of PVL cases.ResultsThere was a total of 49 cases (61 eyes), 37 unilateral (75.5%) and 12 bilateral (24.5%), 32 arterial type (65.3%) and 18 venous type (36.7%) (one patient had either kind in each eye). The mean number of loops per eye was 2.7 (range, 1–7). The loops were asymptomatic in 42 cases (85.7%). Other findings included: the presence of cilioretinal artery (14 cases), retinal vascular tortuosity (26 cases), amaurosis fugax (1 case), branch retinal artery occlusion (1 case) and vitreous haemorrhage (3 cases). Six morphologic loop types could be discerned based on elevation (flat vs. elevated), shape (figure of 8 or corkscrew with hyaline sheath), number (multiple or single), location (central or peripheral), lumen size (arterial vs. arteriolar) and presence of vascular tortuosity or vitreous traction.ConclusionsPVL are usually asymptomatic and can be divided into six morphologic types with different pathogenesis during early embryogenesis.Subject terms: Anatomy, Physiology     

Smartphones in ophthalmology

The potential usefulness of smartphones in the medical field is evolving everyday. This article describes various tools available on smartphones, largely focusing on the iPhone, for the examination of an ophthalmic patient, for patient and physician education, as well as reference tools for both ophthalmologists and vision researchers. Furthermore, the present article discusses how smartphones can be used for ophthalmic photography and image management, and foremost, the usefulness of the applications such as the Eye Handbook for the ophthalmologist and interested students, patients, physicians, and researchers, currently available in the iPhone.