No abstract

Pseudophakic cystoid macular edema (PCME) is the most common complication of cataract surgery, leading in some cases to a decrease in vision. Although the pathogenesis of PCME is not completely understood, the contribution of postsurgical inflammation is generally accepted. Consequently, anti-inflammatory medicines, including steroids and nonsteroidal anti-inflammatory drugs, have been postulated as having a role in both the prophylaxis and treatment of PCME. However, the lack of a uniformly accepted PCME definition, conflicting data on some risk factors, and the scarcity of studies comparing the role of nonsteroidal anti-inflammatory drugs to steroids in PCME prevention make the problem of PCME one of the puzzles of ophthalmology. This paper presents an updated review on the pathogenesis, risk factors, and use of anti-inflammatory drugs in PCME that reflect current research and practice.

Purpose. To present a new method of measuring ocular axial dimensions, termed OCT biometry (B-OCT). Design. Observational cross-sectional study and evaluation of new diagnostic technology. Methods. B-OCT was implemented in the spectral domain OCT device for posterior and anterior segment imaging (REVO NX, Optopol Technology). A total of 349 eyes (214 of healthy subjects, 115 of patients with cataract, and 20 with severe macular diseases) were enrolled in the study. The results of B-OCT were compared to swept source OCT-based IOLMaster 700 (Carl Zeiss Meditec). Differences in measurement values between the two biometers were determined using the paired t-test. Agreement was assessed through intraclass correlation coefficients (ICCs) and Bland–Altman plots. Results. B-OCT obtained with REVO NX provides excellent interobserver reproducibility (ICC for: axial length (AXL) = 1.000; central corneal thickness (CCT) = 0.933; anterior chamber depth (ACD) = 0.933; lens thickness (LT) = 0.985) and intraobserver repeatability (ICC for: AXL = 1.000; CCT ≥ 0.994; ACD = 0.998; LT ≥ 0.993). The correlation between measurements made using both devices was outstanding (ICC for: AXL, healthy = 1.000; AXL, cataractous = 1.000; ACD, healthy = 0.998; ACD, cataractous = 0.997; LT, healthy = 0.998; LT, cataractous = 0.997; CCT, healthy = 0.989; CCT, cataractous = 0.979). The mean AXL measurement difference in healthy eyes was −0.001 ± 0.016 mm (the 95% LoA ranged from −0.034 to 0.031); mean ACD difference was 0.000 ± 0.024 mm (95% LoA, −0.047 to 0.047); mean LT difference was −0.002 ± 0.024 mm (95% LoA, −0.050 to 0.046); and mean CCT difference  was −0.8 ± 5.1 μm (95% LoA, −10.81 to 9.26). The mean AXL measurement difference in cataractous eyes was −0.003 ± 0.022 mm (95% LoA, −0.046 to 0.039); mean ACD difference was 0.003 ± 0.029 mm (95% LoA, −0.054 to 0.059); mean LT difference was −0.002 ± 0.025 (95% LoA, −0.051 to 0.048); and mean CCT difference was 2.7 ± 6.4 μm (95% LoA, −9.80 to 15.7). Conclusion. The study shows small, nonsignificant differences between the biometric measurements obtained with REVO NX B-OCT and IOLMaster 700, which is of high significance for IOL power selection. As B-OCT utilizes a conventional OCT device, the measurements of the ocular axial dimensions are combined with high-resolution macular scans for the simultaneous assessment of central retina as a part of screening for macular pathology. The presented method is the first spectral domain OCT-based biometry technique and the only one integrated into a standard OCT device. Thus, it brings novel functionality to OCT technology.

We present a computationally efficient, semiautomated method for analysis of posterior retinal layers in three-dimensional (3-D) images obtained by spectral optical coherence tomography (SOCT). The method consists of two steps: segmentation of posterior retinal layers and analysis of their thickness and distance from an outer retinal contour (ORC), which is introduced to approximate the normal position of external interface of the healthy retinal pigment epithelium (RPE). The algorithm is shown to effectively segment posterior retina by classifying every pixel in the SOCT tomogram using the similarity of its surroundings to a reference set of model pixels from user-selected area(s). Operator intervention is required to assess the quality of segmentation. Thickness and distance maps from the segmented layers and their analysis are presented for healthy and pathological retinas.

Diabetic maculopathy (DM) is one of the major causes of vision impairment in individuals with diabetes. The traditional approach to diagnosis of DM includes fundus ophthalmoscopy and fluorescein angiography. Although very useful clinically, these methods do not contribute much to the evaluation of retinal morphology and its thickness profile. That is why a new technique called optical coherence tomography (OCT) was utilized to perform cross-sectional imaging of the retina. It facilitates measuring the macular thickening, quantification of diabetic macular oedema, and detecting vitreoretinal traction. Thus, OCT may assist in patient selection with DM who can benefit from treatment, identify what treatment is indicated, guide its implementing, and allow precise monitoring of treatment response. It seems to be the technique of choice for the early detection of macular oedema and for the followup of DM.

No abstract

Corneal evaluation in ophthalmology necessitates cellular-resolution and fast imaging techniques allowing accurate diagnoses. Currently, the fastest volumetric imaging technique is Fourier-domain full-field optical coherence tomography (FD-FF-OCT) that uses a fast camera and a rapidly tunable laser source. Here, we demonstrate high-resolution, highspeed, non-contact corneal volumetric imaging in vivo with FD-FF-OCT that can acquire a single 3D volume with a voxel rate of 7.8 GHz. The spatial coherence of the laser source was suppressed to prevent it from focusing to a spot on the retina, and therefore, exceeding the maximum permissible exposure (MPE). Inherently volumetric nature of FD-FF-OCT data enabled flattening of curved corneal layers. Acquired FD-FF-OCT images revealed corneal cellular structures, such as epithelium, stroma and endothelium, as well as subbasal and midstromal nerves.

Disseminated disruptions of the IS/OS junction seen on SOCT cross-sectional images in the acute stage of MEWDS form the pattern of spots that can be correlated with those revealed by ICGA. This suggests that hypofluorescent ICGA spots indicate alternations in the retinal pigment epithelium-photoreceptor complex and do not represent inflammatory choroidal lesions.