The analysis of tear meniscus parameters during daily soft contact lens wear using optical coherence tomography.

PURPOSE: To evaluate tear meniscus parameters in soft contact lens wearers (SCL) using optical coherence tomography (OCT) and ImageJ software. METHODS: This prospective study included 50 soft contact lens wearers (group 1: 25 symptomatic SCL wearers (SCLW), group 2: 25 asymptomatic SCL wearers (ASCW)) and 25 healthy non-CL wearers (group 3 (NCLW)). SCLs were fitted on each eye of CL wearers, and the lower tear meniscus was imaged using OCT before CL insertion, immediately afterward, and reimaged 2, 5 and 10 h after insertion. Tear meniscus parameters, including tear meniscus height (TMH), depth (TMD), turbidity, and percentage area occupied by particles (PAOP) were measured in all groups. RESULTS: Turbidity and PAOP measurements at baseline in SCLW were significantly higher than in other groups (p < 0.05). There was no significant difference between TMH, TMD, turbidity, and PAOP parameters calculated at baseline visit and two hours after SCL insertion in all groups (p > 0.05 for 2 comparisons). The symptomatic SCL users had a significant decrease in TMH and TMD in the fifth hour. The turbidity and PAOP measurements of SCLW and ASCW at the fifth and tenth hours were significantly higher than those of NCLW (p < 0.05). CONCLUSION: TMD and height TMH decrease throughout the day in all participants; however, a significant decrease in these parameters was observed only in symptomatic SCL users at the fifth hour, at the earliest. As the duration of CL wear increases, turbidity and PAOP even in asymptomatic SCL wearers become significantly higher than those in healthy non-CL wearers. KEY MESSAGES: What Is Known • Contact lens wear is associated with an increased risk of dry eye. • Tear volume decreases gradually during contact lens wear. What Is New • Tear meniscus turbidity and particle area occupied by particles (PAOP) were higher in symptomatic contact lens wearers and they increase gradually during contact lens wear. • Tear meniscus turbidity and PAOP may be measures of how well the tear film and meniscus are functioning in contact lens wearers.

Impaired brachial flow-mediated dilation may predict choroidal and retinal nerve fibre layer thickness changes in people with obesity.

CLINICAL RELEVANCE: Choroidal thickness and peripapillary retinal nerve fibre layer (RNFL) changes are known to occur in obesity. Endothelial dysfunction and systemic atherosclerosis may play a role in the pathophysiology of these differences. BACKGROUND: Flow-mediated dilation (FMD) is reduced in patients with endothelial dysfunction, and the ankle-brachial index is a surrogate marker for atherosclerosis. This study was conducted to examine the relationship between systemic vascular parameters (FMD, and ankle-brachial index), subfoveal choroidal thickness, and peripapillary RNFL thickness in obese individuals. METHODS: This observational, cross-sectional study involved 108 total participants who were divided into two groups. One group consisted of 54 obese subjects who each had a body mass index of 30 kg/m2 or more. The other control group contained 54 participants who each had a body mass index of 25 kg/m2 or less but higher than 20 kg/m2 . For each participant, only one eye was examined in this study. Subfoveal choroidal thickness, RNFL thickness, ankle-brachial index, and ultrasound measurement of the brachial artery FMD were performed. FMD was categorised according to receiver operating characteristic analysis, and endothelial dysfunction was defined as an FMD ≤ 7.29%. RESULTS: Subfoveal choroidal and RNFL thicknesses in the temporal quadrant were significantly lower in the obese group (p < 0.05). Lower mean values of subfoveal choroidal and RNFL thicknesses in the temporal and inferior quadrants were observed in subjects with an FMD ≤ 7.29% (p < 0.05). In people with obesity, FMD was positively correlated with subfoveal choroidal thickness (r = 0.322, p = 0.001), inferior RNFL thickness (r = 0.259, p = 0.007), and temporal RNFL thickness (r = 0.297, p = 0.002). However, the ankle-brachial index was not correlated with obesity. CONCLUSIONS: Impaired FMD was associated with reduced subfoveal choroidal and RNFL thicknesses in the temporal and inferior quadrants of people with obesity.

Evaluation of the Tear Meniscus Using Optical Coherence Tomography in Meibomian Gland Dysfunction.

INTRODUCTION: This study aimed to evaluate tear meniscus parameters in meibomian gland dysfunction (MGD) using optical coherence tomography and ImageJ software. METHODS: We enrolled 66 eyes of 66 participants and measured tear meniscus parameters, including height, depth, turbidity, and percentage area occupied by particles (PAOP) in the meniscus in the MGD and control groups. RESULTS: Tear meniscus turbidity and PAOP were significantly higher in the MGD group, but tear meniscus height (TMH) and depth (TMD) did not differ significantly between groups. Tear meniscus turbidity and PAOP were positively correlated with each other and ocular surface parameters, including OSDI and ocular surface staining scores. CONCLUSION: Tear meniscus turbidity and PAOP were higher in the MGD group than in the control group; therefore, they can be used as significant non-invasive parameters in the prediction of MGD. TMH and TMD did not differ significantly between groups.

Retinal Vascular Changes in Patients with Chronic Obstructive Pulmonary Disease: An Optical Coherence Tomography Angiography Study.

OBJECTIVES: In the current study, we aimed to investigate retinal vascular density and blood flow changes in patients with chronic obstructive pulmonary disease (COPD) using optical coherence tomography angiography (OCTA) (AngioVue Avanti, Optovue). METHODS: Thirty eyes of 30 patients with COPD and 30 eyes of 30 healthy controls were evaluated with OCTA. Foveal and parafoveal vessel density, inner retinal and choriocapillary flow area, and foveal avascular zone (FAZ) area were measured and compared between the groups. RESULTS: No statistically significant differences were observed in the outer retinal flow area and choriocapillary flow area measurements between the groups (p=0.609 and p=0.162, respectively). There was no statistically significant difference in FAZ and FAZ perimeter values between the groups (p=0.725 and p=0.820, respectively). Vascular density measurements in the superficial foveal and parafoveal areas were not statistically significantly different between the groups (p>0.05, for all). Deep parafoveal vascular density values of the COPD group were statistically significantly lower than the control group in all investigated areas except the superior and inferior quadrants. CONCLUSION: The results of our study demonstrated for the first time that vascular density decreased in the parafoveal area due to COPD-related hypoxemia and endothelial dysfunction.

Microvascular and functional changes according to the fundus location of the affected arteriovenous crossing in patients with branch retinal vein occlusion.

Purpose: The aim of this study was to evaluate the structural and functional changes occurring in patients with branch retinal vein occlusion (BRVO) according to the distance of the affected arteriovenous (AV) crossing to the centers of the fovea and optic disc by optic coherence tomography angiography (OCTA). Methods: Forty-five patients with unilateral BRVO and 45 age- and sex-matched healthy controls were included in this retrospective observational study. Images of the macula (3 mm × 3 mm) and affected AV crossing sites were obtained by OCTA. The fovea-AV crossing distance (FAVD), optic disc-AV crossing distance (DAVD), and optic disc-fovea distance (DFD) were measured. Results: The FAVD/DFD ratio was positively correlated with the vessel density in the superficial and deep affected hemifields (r = 0.430, P < 0.05 and r = 0.308, P < 0.05, respectively) and negatively correlated with the superficial foveal avascular zone and logarithm of the minimum angle of resolution (logMAR) visual acuity (r = -0.412, P < 0.05 and r = -0.356, P < 0.05, respectively). The DAVD/DFD ratio was not correlated with the logMAR visual acuity, superficial FAZ area or vessel densities in the affected hemifield (all P > 0.05). Conclusion: The affected AV crossing site that was further away from the fovea had better visual acuity and quantitative microvascular parameters in the affected hemifields. However, this correlation was not observed for the distance between the affected AV crossing site and the optic disc.

The Effect of Two Different Frontalis Sling Approaches on Postoperative Eyelid Contour: A Comparative Study.

PURPOSE: To compare two different frontalis sling approaches, tarsal fixation and orbicular muscle fixation, using silicone rod (FCI Ophthalmics, Marshfield Hills, MA, USA) in terms of postoperative upper eyelid contour in patients with poor levator muscle function. DESIGN: Retrospective, comparative, case series. METHODS: Ten eyes of seven patients who received frontalis sling surgery with orbicularis muscle fixation (group 1), eight eyes of seven patients who received frontalis sling surgery with tarsal fixation (group 2) and 30 eyes of 15 age and sex-matched healthy controls (control group) were included. Postoperative photographs of all the participants were taken in the primary gaze, and each photograph was viewed on a computer. The distance between the upper lid margin and pupillary center (MCD), nasal limbus (MND), and temporal limbus (MTD) was measured, respectively, using the ruler in Microsoft Paint Software and compared with each other for each participant. RESULTS: Both nasal, central and temporal margin distance values in group 1 and group 2 were significantly lower than those of the control group (p < 0.05 for all values). The ratio of MTD/MCD in the control group was significantly higher than group 1 (p = 0.04) besides the ratio of MND/MTD in the control group was significantly lower than group 1 (p = 0.01). DISCUSSION: Frontalis sling approach with tarsal fixation using silicone rod might provide improved cosmetic results including more symmetrical upper eyelid contour compared with orbicularis muscle fixation approach. Moreover, the novel measuring technique presented in the current study provides a simple and effective assessment of the upper lid contour in daily practice setting. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Short term effects of intravitreal anti-vascular endothelial growth factor agents on cornea, anterior chamber, and intraocular pressure.

Objective: To evaluate short term changes in anterior chamber depth (ACD), central corneal thickness (CCT), intraocular pressure (IOP), and corneal endothelial cell density (ECD) after intravitreal anti-vascular endothelial growth factor (VEGF) injections. Materials and methods: A total of 100 eyes from 100 patients, who were naive for intravitreal injection treatment, were included in this retrospective study. Patients who received only a single type of intravitreal anti-VEGF injections (bevacizumab, ranibizumab, or aflibercept) for two consecutive months were examined. ACD, CCT, IOP, and ECD measurements were taken at pre-injection and one month after the first and second injections and were compared. Results: The mean corneal ECD for all eyes and phakic eyes was significantly lower one month after the first (p = 0.041 and p = 0.047, respectively) and second injections (p = 0.013 and p = 0.034, respectively) compared to the values at pre-injection levels. Similarly, the mean ACD of all eyes and phakic eyes was significantly lower one month after the first (p < 0.001 and p < 0.001, respectively) and second injections (p < 0.001 and p < 0.001, respectively) compared to the values at pre-injection levels. However, there was no significant difference in pseudophakic eyes one month after the first and second injections (ECD, p = 0.28 and p = 0.23; ACD, p = 0.75 and p = 0.71, respectively). There was no significant change in IOP and CCT values at pre-injection and one month after the first and second injections for all eyes and for both the phakic and pseudophakic eyes. Discussion: After the anti-VEGF injections, IOP and CCT values were not significantly changed and were similar in all eyes and phakic eyes; however, in these groups, there was a small but statistically significant decrease in ACD and ECD. On the contrary, there was no significant difference in pseudophakic eyes. Clinicians performing intravitreal injections must be aware of these associations for a better understanding of ACD and ECD changes in phakic eyes.