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Background/purpose When evaluating skin care products for human skin, quantitative test methods need to be simple, precise and reliable. Optical coherence tomography ( OCT), provides high-resolution sectional images of translucent materials to a depth of a few millimeters, a technique usually applied to medical measurements in ophthalmology and dermatology. This study aimed to demonstrate the application of OCT as the main technique for monitoring changes in skin topography during tests of a wrinkle-reduction product in humans. Methods We used a commercial OCT apparatus to perform clinical examinations of skin roughness in treated and non-treated sites in the periorbital region of thirty human voluntaries who were using an anti-aging product commercially available: Natura Chronos® Flavonóides de Passiflora 45+ FPS15, from Natura Cosméticos, Brazil. Measurements were performed days 0, 7, 14 and 28 of treatment. Equipment and software allowed real-time recording of skin roughness parameters and wrinkle depths. Results The OCT measurements have allowed the monitoring of changes in skin roughness, which have shown reduction in treated sites around 10%. The obtained depth distributions also indicate reduction in the occurrence of wrinkles deeper than 170 μm. The verified results are consistent with those typically obtained after successful treatment with modern anti-aging products. Conclusion By using the OCT technique, it was possible to quantify changes in skin roughness and in the distribution of depths of skin wrinkles, with adequate sensitivity. OCT imaging allows the direct visualization of the skin topography with resolution of micrometers, a reliable and interactive tool for clinical use. Therefore, for the first time, we demonstrated the use of OCT technique to verify the efficacy of cosmetic products in real time. [ABSTRACT FROM AUTHOR]

Purpose To evaluate choroidal thickness (CT) in diabetic patients without diabetic retinopathy (DR) using enhanced depth imaging spectral-domain optical coherence tomography (EDI SD- OCT). To correlate CT with disease duration, systemic blood pressure (BP), glycemia, intraocular pressure (IOP) and ocular pulse amplitude (OPA). Methods Prospective, observational case-control study. A complete ophthalmological examination was performed (visual acuity, refraction, Goldmann applanation and dynamic contour tonometries, fundoscopy and axial length). CT was assessed by a non-invasive procedure using an EDI- OCT (Spectralis Heidelberg) at 13 locations (subfoveal and 3 measurements 500 μm apart in all 4 directions - nasal, temporal, superior and inferior). Results 180 patients were recruited: 130 diabetic patients with no DR and 50 healthy controls; one eye per patient included in the study. CT at 1500 μm above the fovea was significantly thicker in the diabetic group (239.9 ± 56 μm vs 268.2 ± 67.7 μm, p = 0.001). None of the other topographic region comparisons were statistically different (p > 0.05). In diabetic patients CT was not correlated with disease duration, BP, glycemia or IOP. CT was positively correlated with OPA in 12 points in diabetic patients (r between 0.19 and 0.27, p < 0.05) but not in the control group. CT variation coefficients in the diabetic group were statistically lower than in the control group (p < 0.01). Conclusions The thickening of the choroid at 1500 μm superior of the fovea in diabetic patients without DR may correspond to the diabetic choroidopathy in mid-periphery presented before DR. Moreover, this tissue may be functionally different, as the pattern of correlations seems to differ between groups. Further studies are needed to explore these differences and the potential of the CT in the clinical setting. [ABSTRACT FROM AUTHOR]

Purpose The authors intend to present an analysis and comparison of the choroidal thickness in more distant superior regions. Choroidal thickness is increased in a heterogeneous pattern superiorly to the fovea in diabetic patients without diabetic retinopathy. Methods Observational case-control study of 60 eyes of 60 patients with diabetes mellitus type 2 without diabetic retinopathy. A control group of 31 eyes of 31 patients without diabetes with similar demographic features was also created. All the patients were recruited from the same outpatient clinic. Enhanced depth imaging spectral-domain optical coherence tomography (EDI SD- OCT SPECTRALIS®) was performed and high-resolution macular scans were obtained. Choroidal thickness was evaluated 2000 μm superiorly to the fovea by manual layer segmentation. Previous studies have validated the validity of using a manual layer segmentation procedure in OCT. Statistical analysis was done with SPSS Statistics. A p value <0.05 was considered statistically significant. Results Diabetic patients were in average 67.0 ± 9.6 years old and 56.7% were male. Average choroidal thickness 2000 μm superiorly to the fovea was 287.77 ± 74.32 μm in diabetic patients and 249.81 ± 53.96 μm in non-diabetic patients. There was a significant increase in choroidal thickness in diabetic patients when compared to non-diabetic patients (T-student, p = 0.014). Conclusions Choroidal thickness can be accurately measured using high-definition macular OCT scans. This study documented structural differences in the choroid associated with diabetes mellitus type 2 that are not only present in the central foveal area as reported in previous studies. Diabetes Mellitus is associated with multiple microvascular dysfunctions that are probably coupled with choroidal vascular modifications that induce changes in thickness. [ABSTRACT FROM AUTHOR]

Purpose To investigate the association between anterior lamina cribrosa depth (ALCD) determined with enhanced depth imaging spectral-domain optical coherence tomography (EDI- OCT) and IOP in a healthy Portuguese population. Methods Prospective observational study conducted between January and April 2015 of 44 subjects with a irrelevant ophthalmologic history. EDI- OCT of optic nerve head (ONH) was performed in all participants (2 cross scans: vertical and horizontal). ALCD was defined as the perpendicular distance between the line connecting both edges of Bruch's membrane and the anterior border of the lamina cribrosa, at the maximum depth point. An experienced operator manually segmented ALCD and a mean of the two consecutive blinded measurements was computed. To guarantee observations' independence, only one eye was considered per subject. Only high-quality images were accepted. The tenets of the Declaration of Helsinki were followed. Statistical analyses were performed using STATA 13.0. Results Studied population included 44 subjects (26 women), with a mean age of 62.9 ± 14.3 years. Mean vertical and horizontal maximum ALCD was 453.3 ± 88 μm and 436.1 ± 78.7 μm, respectively. Neither gender nor age were associated with these ALCD scans (p > 0.05). When controlling for gender, age and spherical equivalent, maximum vertical and horizontal ALCD increased, respectively, by 8.8 μm (95% confidence interval [ CI], 0.6-17.0 μm; p = 0.04) and 8.1 μm (95% CI, 0.4-15.7 μm; p = 0.04) per mmHg increase in IOP. Conclusions Our sample of healthy subjects presented a statistically significant positive linear relation between IOP and ALCD, when controlling for possible confounding factors. Our results may trigger furthers studies to better elucidate the role of IOP in morphological and functional dynamics of the ONH. [ABSTRACT FROM AUTHOR]

Purpose To determine intra and inter-rater agreement of anterior lamina cribrosa depth (ALCD) manual measurements using enhanced depth imaging spectral-domain optical coherence tomography (EDI- OCT). Methods Double blind prospective observational study between December 14 and May 15. EDI- OCT of optic nerve head was performed in subjects with an irrelevant ophthalmologic history (2 cross scans: vertical and horizontal). ALCD was defined as the perpendicular distance between the line connecting both edges of Bruch's membrane and the anterior border of the lamina cribrosa, at the maximum depth point. Two double-blinded experienced operators manually measured ALCD twice, with a one-month interval. Intra and inter-rater agreement was evaluated using intraclass correlation coefficients (ICC), concordance correlation coefficients (CCC) and Bland-Altman (BA) plots for the right eye vertical (RV) and horizontal (RH) scans and left eye vertical (LV) and horizontal (LH) scans. Statistical analyses were performed using STATA 13.0. Results Studied population included 44 subjects (26 women), with a mean age of 62.9 ± 14.3 years. Mean vertical and horizontal maximum ALCD was 453.3 ± 88 μm and 436.1 ± 78.7 μm, respectively. Intra-rater ICC for ALCD in RV, RH, LV and LH were 0.98, 0.94, 0.97 and 0.96, respectively. Inter-rater ICC for ALCD in RV, RH, LV and LH were all 0.99. Intra-rater CCC for ALCD in RV, RH, LV and LH were 0.98, 0.93, 0.97 and 0.96. Inter-rater CCC for ALCD in RV, RH, LV and LH were all 0.99. Bland-Altman plots suggested that almost all observations were within the 95% limits of agreement. Conclusions ALCD manual measurements with EDI- OCT showed high agreement among intra and inter-rater measurements in healthy eyes. EDI- OCT is a reliable tool for ALCD measurement, which can provide potentially useful information for integrated glaucoma management. [ABSTRACT FROM AUTHOR]

Purpose To present a comparison of the thickness variation of the different retinal layers in diabetic patients without diabetic retinopathy. Methods A prospective observational study was performed. 175 eyes of 175 patients: 125 diabetic patients without diabetic retinopathy and 50 subjects without diabetes (age and gender matched) from the ophthalmology outpatient clinic were included. Optical Coherence Tomography (OCT SPECTRALIS®) was performed with high-resolution macular scans. Automated retinal layer segmentation was performed using validated software and layers thicknesses were determined. The coefficient of variation of the different layers was calculated. A p value < 0.05 was considered statistically significant. Results Diabetic patients were in average 66.9 ± 9.3 years old. There weren't significant differences in the coefficients of variation between diabetic and non-diabetic patients: total retinal thickness (9.3% vs. 9.3%; p = 0.39), RNFL (41.09% vs. 42.25%; p = 0.33), GCL (30.39% vs. 31.13%; p = 0.20), IPL (23.62% vs. 24.13; p = 0.40), ILN (21.26% vs. 19.86; p = 0.44). Conclusions Previous studies have demonstrated that choroidal thickness coefficient of variation is lower in diabetic patients. Nevertheless, in retinal layers no difference was found in diabetic patients without macular edema. There is a combination of choroid with diminished thickness coefficient of variation and retinal layers with normal thickness coefficient of variation. This suggests that vascular choroidal pathology precedes retinal layers dysfunction. Exudation and lipid accumulation associated with microvascular retinal dysfunction and changes in axonal homeostasis only appear at a second step. This study emphasizes the importance of the retinal layer thickness measurement with OCT in the evaluation of diabetic patients. [ABSTRACT FROM AUTHOR]

Purpose To evaluate retinal layers thickness in diabetic patients without diabetic retinopathy (DR) using spectral-domain optical coherence tomography (SD- OCT). To correlate retinal layers thickness in diabetic patients with disease duration, systemic blood pressure ( BP), glycemia, glycosylate haemoglobin (HbA1c), intraocular pressure (IOP) and ocular pulse amplitude (OPA). Methods Prospective, observational case-control study. A total of 175 eyes from 175 patients (125 diabetic patients without DR; 50 healthy controls) were recruited from the outpatient clinic in a tertiary center. A complete ophthalmological examination was performed (visual acuity, refraction, Goldmann applanation and dynamic contour tonometries, fundoscopy, axial length and SD- OCT-Spectralis®). After automated retinal segmentation the thickness of each layer was calculated in the 9 ETDRS areas. Results A significant increase of retinal nerve fiber layer (RNFL) thickness in inner and outer rings was found in diabetic eyes vs. controls (p between <0.0001 and 0.02). Thickness was also increased in specific sites of ganglion cell layer (GCL), inner nuclear layer (INL) and retinal pigment epithelium (RPE) in diabetic eyes (p between 0.001 and 0.03). A significant decrease of outer plexiform layer (OPL) was detected in diabetic eyes at two sites of the inner ring (p = 0.04 and p < 0.0001). The different retinal layers weren't correlated with systemic BP, glycemia, HbA1c, IOP and OPA, but the photoreceptor layer was negatively correlated with disease duration at 3 sites (r between −0.18 and −0.21, p < 0.05). Conclusions In diabetic patients without DR thickness of the inner retina seems to be increased. This suggests that metabolic and morphological changes of the cells of these inner retinal layers occur early and before the apoptosis and neural degeneration. [ABSTRACT FROM AUTHOR]