High body weight-related retinal vasculopathy in children with obesity.

PURPOSE: To investigate the foveal avascular zone (FAZ) and the microvascular alterations in both macula and peripapillary region in obese children. METHODS: We included a total of 222 eyes of 111 children (54 obese children and 57 healthy subjects). Capillary vessel density (VD) of superficial (SCP) and deep (DCP) retinal capillary plexuses were measured in macular slabs. Peripapillary region was also evaluated. The FAZ parameters were measured based on the whole retinal slab. A commercial optical coherence tomography-angiography system was used. RESULTS: The mean ages were 13.33 ± 2.55 years (range, 8-17) and 13.41 ± 2.90 years (range, 7-18) in patients with obesity and healthy controls, respectively (p = 0.84). The mean area of the FAZ were 0.278 ± 0.10 mm2 and 0.272 ± 0.11 mm2 in children with obesity and in control participants, respectively (p = 0.68). There were significant increases in the superior region of the parafoveal VD of SCP (p = 0.008 for superior hemisphere and p = 0.003 for superior quadrant). There was no significant difference in any measure of the macular DCP and peripapillary region (p > 0.05, for all). CONCLUSION: Increased vascular density measurements were found in the superior part of the parafoveal region of SCP in children with obesity. The results of the study should be taken into consideration during the course of the disease to define whole systemic response to obesity in childhood and will be of interest for pediatrician's clinical practice.

Evaluation of microvascular changes in retinal zones and optic disc in pediatric patients with type 1 diabetes mellitus.

PURPOSE: The objective of this study was to evaluate the vascular parameters of the retinal zones and the optic disc (OD) with the use of optical coherence tomography angiography (OCTA) in pediatric patients with type 1 diabetes mellitus (T1DM). METHODS: This study enrolled 60 patients with T1DM without clinically detectable diabetic retinopathy (DR), along with 59 age-, gender-, and pubertal stage-matched controls. The ages of the participants in both groups were < 18 years. Retinal and OD measurements were carried out with OCTA. Foveal avascular zone (FAZ) area, non-flow area (NFA), FAZ perimeter (PERIM), acircularity index of FAZ (AI, the rate of the perimeter of FAZ and the perimeter of a circle with equal area), foveal density (FD), superficial (SCP), and the deep capillary plexus (DCP) were analyzed in the macular region. SCP and DCP were also scanned centered on the OD. Correlations between the OCTA parameters with duration of DM, glycated hemoglobin (HbA1c) levels, and microalbuminuria were evaluated among patients with T1DM. RESULTS: The mean values for NFA were significantly higher and mean FD were significantly lower in the diabetic group compared with the controls (p = 0.02 and p = 0.01, respectively). The mean values for SCP and DCP were significantly lower in diabetic group (p < 0.05). The mean values for capillary density in the OD were also significantly lower in diabetic group (p < 0.05). There were correlations between the duration of T1DM, HbA1c levels and microalbuminuria, and the investigated parameters of OCTA. CONCLUSIONS: The presence of microvascular changes in both retinal zones and the OD in children with T1DM without retinopathy is an important data. OCTA can be used for the early detection of DR in children.

Evaluation of retinal microvasculature and foveal avascular zone by the optical coherence tomography angiography in pediatric migraine patients.

To compare the foveal avascular zone (FAZ), macular and peripapillary vessel density and retinal nerve fiber layer (RNFL) thickness between pediatric migraine patients and healthy subjects. A total of 108 eyes of 54 children with migraine without aura and 94 eyes of 47 age- and gender-matched healthy subjects were included. Capillary vessel density (CVD) in superficial (SCP) and deep (DCP) retinal capillary plexus, peripapillary region, FAZ, and RNFL thickness were analyzed by optical coherence tomography-angiography. The mean ages were 12.4 ± 3.3 years (range 6-18) in patients with migraine and 12.6 ± 2.9 years (range 5-18) in healthy controls (p = 0.742). The mean FAZ area measured 0.27 ± 0.09 mm2 in the pediatric migraineurs and 0.26 ± 0.09 mm2 in healthy controls (p = 0.53). There was no significant difference in any measurement of SCP, DCP, peripapillary CVD, and RNFL thickness between study groups (p > 0.05 for all). The pediatric migraine disability assessment test (PedMIDAS) negatively correlated with some of the CVD and RNFL measurements in pediatric migraine patients (p < 0.05). The macular and peripapillary microvasculature were not significantly different during an attack-free period in pediatric migraine patients than in healthy subjects.

Evaluation of retinal vascularization by optical coherence tomography angiography (OCTA) in rheumatoid arthritis, and its relationship with disease activity.

PURPOSE: To measure the retinal capillary density quantitatively with optical coherence tomography angiography (OCTA) in patients with rheumatoid arthritis (RA) and healthy controls (HCs), and to evaluate the relationship between OCTA findings and RA disease activity. METHODS: In this cross-sectional study, 106 eyes of RA patients and 71 eyes of HCs were evaluated. RA patients were divided into inactive (DAS28 < 3.2) and active (DAS28 ≥ 3.2) subgroups. Retinal capillary plexus density (CPD) was obtained from the superficial capillary plexus (SCP), deep capillary plexus (DCP), and radial peripapillary capillary (RPC). RESULTS: In RA patients and HCs, the CPD (%) was 50.99 ± 3.30 and 52.08 ± 2.36 (p = .013) in the SCP, 55.65 ± 5.73 and 57.53 ± 4.60 (p = .019) in the DCP, and 49.98 ± 2.25 and 49.93 ± 2.25 (p = .947) in the RPC blood supply regions, respectively. In inactive and active RA patients, the CPD (%) was 51.01 ± 2.92 and 50.97 ± 3.73 (p = .947) in the SCP, 55.02 ± 5.70 and 56.40 ± 5.74 in the DCP (p = .229), and 50.34 ± 2.23 and 49.55 ± 2.22 (p = .079) in the RPC blood supply regions, respectively. DAS28 was negatively correlated with CPD in RPC blood supply region (Rho = -0.272, p = .006). CONCLUSION: In RA, retinal CPD in the macula is lower than HCs. Although retinal CPD is not generally different in active and inactive RA patients, capillaries in the optic disc may be affected by disease activity.

Subclinical retinal microvascular alterations assessed by optical coherence tomography angiography in children with systemic hypertension.

PURPOSE: To compare the foveal avascular zone (FAZ) macular and peripapillary vessel density between children with high blood pressure and healthy subjects. METHODS: A total of 40 eyes of 20 children with hypertension and 40 eyes of 20 age- and sex-matched healthy controls were included. Capillary vessel density (CVD) in superficial (SCP) and deep (DCP) retinal capillary plexus, peripapillary region, and FAZ were analyzed by optical coherence tomography angiography. RESULTS: The mean ages were 15.2 ± 1.5 years (range, 10-18) in patients with hypertension and 14.4 ± 2.8 years (range, 10-18) in healthy controls (P = 0.742). The mean FAZ area measured 0.25 ± 0.10 mm2 in children with hypertension and 0.25 ± 0.09 mm2 in healthy controls (P = 0.765). There was no significant difference between study groups in any measure of the macular SCP (P > 0.05 for all); however, the mean whole image, inferior hemisphere, and para- and perifoveal measurements of the macular DCP were significantly lower in children with hypertension than in controls (P < 0.05 for all). CONCLUSIONS: Although there was no evidence of hypertensive retinopathy, subthreshold microvascular alterations were found in the DCP of the retinal circulation in pediatric hypertensives. These alterations should be considered as prognostic cues when defining whole systemic response to high blood pressure in childhood.

Surgical and Immunohistochemical Outcomes of Scleral Reconstruction with Autogenic, Allogenic and Xenogenic Grafts: An Experimental Rabbit Model.

Purpose: Choukroun's platelet-rich fibrin (PRF), a second-generation platelet concentrate, has unique morphological and chemical features and may be considered as a scaffold for scleral reinforcement and regeneration. The purpose of this study was to compare the use of xenogenic human-derived amniotic membrane (HAM), allogenic sclera, and autogenic PRF in rabbit lamellar scleral defect model with respect to both anatomical and immunohistochemical improvement. Methods: A total of 45 adult New Zealand rabbits were randomized into five groups: normal control; without surgical procedure, negative control; scleral defect model (SDM), xenogenic HAM; SDM+HAM graft, allogenic sclera; SDM+allogenic sclera graft, autogenic PRF; SDM+autogenic PRF graft. Clinical findings, Hematoxylin&Eozin (HE), Masson Trichrome, Verhoeff Acid Fuchsin, Transforming Growth Factor ß Receptor 1, Fibroblast Growth Factor, Bone Morphogenetic Protein 2, collagen type 1, aggrecan, and Matrix Metalloproteinase 2 were evaluated. Results: Ocular surface inflammation was significantly lower in normal control and autogenic PRF groups (p < .001). Graft was avascular and not integrated to scleral wound area in 25% rabbits of allogenic sclera group (p = .02), was out of the scleral wound in 33.3% rabbits of xenogenic HAM group (p > .05), all the grafts were at the normal location and viable in autogenic PRF group. The inflammation and vascularization in autogenic PRF group was significantly lower than negative control and xenogenic HAM groups in HE (p < .001). The collagen score of negative control and xenogenic HAM groups were significantly lower than normal control (p < .001) and autogenic PRF (p < .001) groups. There were insignificant differences between allogenic sclera and autogenic PRF groups (p > .05). For immunohistochemistry, the closest values to normal control group were detected in autogenic PRF group for all immunomarkers. Conclusion: Autogenic PRF showed superior features via its excellent anatomical and chemical composition for scleral regeneration when compared to single-layered xenogenic HAM and allogenic sclera grafts.

Corneal Biomechanical Properties in Childhood Obesity.

PURPOSE: To investigate corneal biomechanical properties in patients with childhood obesity. METHODS: The study included 47 patients with childhood obesity (study group) and 39 healthy patients (control group). Corneal hysteresis, corneal resistance factor, corneal compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Ocular Response Analyzer (Reichert, Ophthalmic Instruments, Buffalo, NY) in each eye. Central corneal thickness (CCT), anterior chamber angle (ACA), anterior chamber volume (ACV), and anterior chamber depth (ACD) measurements were obtained by the Pentacam rotating Scheimpflug camera (Oculus Optikgeräte GmBh, Wetzlar, Germany). RESULTS: The mean corneal hysteresis was 10.56 ± 1.52 mm Hg in the study group and 11.16 ± 1.92 mm Hg in the control group (P = .022). The mean IOP was 14.9 ± 2.0 mm Hg in the study group and 14.1 ± 1.3 mm Hg in the control group (P = .003). Corneal hysteresis showed a significant, positive correlation with corneal resistance factor (P < .001, r = 0.851), IOPg (P = .044, r = 0.213), CCT (P < .001, r = 0.477), and IOP (P = .005, r = 0.295). Corneal hysteresis showed a significant, negative correlation with IOPcc (P = .001, r = -0.355), ACA (P = .005, r = -0.294), ACV (P = .019, r = -0.246), and ACD (P = .046, r = -0.211). CONCLUSIONS: Patients with childhood obesity have lower corneal hysteresis and higher IOPcc measurements when compared with healthy patients. Corneal tissue changes may occur in early life in childhood obesity, which could lead to ocular disease in the future. [J Pediatr Ophthalmol Strabismus. 2020;57(2):103-107.].

Effects of iron deficiency anemia on peripapillary and macular vessel density determined using optical coherence tomography angiography on children.

PURPOSE: To evaluate retinal vascular parameters by optical coherence tomography angiography (OCT-A) in iron deficiency anemia (IDA). METHODS: Thirty-two patients with IDA (study group) and 30 healthy children (control group) were enrolled in the study. All subjects underwent a complete ocular examination. OCT-A scans were performed in a 6 × 6 mm area centered on the macula. Foveal avascular zone (FAZ), non-flow area (NFA), FAZ perimeter (PERIM), acircularity index (AI) of FAZ, and foveal density (FD) were measured in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). SCP and DCP were also scanned centered on the optic disk. Hemoglobin (Hb), mean corpuscular volume (MCV), serum iron, total iron-binding capacity (TIBC), and ferritin were also studied and compared for both groups. RESULTS: The mean age was 12.22 ± 4.48 years (ranged 5-18 years) in the study group and 12.37 ± 3.76 years (ranged 6-18 years) in the control group. The mean FAZ value was 0.290 ± 0.09 mm2 in the study group and 0.298 ± 0.11 mm2 in the control group. The mean NFA value was 0.477 ± 0.10 mm2 in the study group and 0.486 ± 0.13 mm2 in the control group (p > 0.05). FD and AI were not statistically significant between the study group and control group (p > 0.05). The mean value for SCP was statistically significant between the study group and control group (p < 0.05). The mean value for DCP was not significantly different between the study and control groups (p > 0.05). The mean values for capillary density on optic disk were also statistically significant between the study group and control group (p < 0.05). A negative correlation was found between serum iron, TIBC, and capillary plexus density (p < 0.05). A positive correlation was found between MCV and ferritin values and capillary plexus density (p < 0.05). CONCLUSION: IDA had significantly lower capillary plexus density. We detected retinal microvascular changes in young IDA patients before significant ocular anomalies, especially ischemic changes, developed.

Optical coherence tomography angiography findings in axial spondylarthritis.

The aim of this study is to evaluate the density of retinal vascular structures and their relationship with disease duration and activity in patients with axial spondylarthritis (axSpA) using optical coherence tomography angiography (OCT-A). In this case-control study, 56 eyes of 29 axSpA patients and 61 eyes of 31 healthy controls (HCs) were evaluated using OCT-A. The capillary plexus density (CPD) of vessels in the parafovea and perifovea regions was evaluated from the superficial capillary plexus (SCP) and deep capillary plexus (DPC) flow areas. The CPD of vessels in the fundus was evaluated from the radial peripapillary capillary (RPC) flow area. Foveal avascular zone (FAZ) size was measured. In axSpA patients and HCs, the mean CPD (%) in the whole retina was 50.75 ± 2.59 and 52.43 ± 2.10 (p < 0.001) in SCP, 54.00 ± 5.83 and 58.37 ± 4.36 (p < 0.001) in DCP, and 50.13 ± 2.32 and 50.13 ± 2.26 (p = 0.984) in RPC flow areas, respectively, and the mean FAZ (mm) was 0.275 ± 0.10 and 0.294 ± 0.07 (p = 0.281), respectively. A significant negative correlation was detected between the CPD and disease duration in the parafovea (ρ: - 0.306, p = 0.022), parafovea superior-hemi (ρ = - 0299, p = 0.025), parafovea inferior-hemi (ρ = - 0.270, p = 0.044), parafovea temporal (ρ = - 0.349, p = 0.008) and parafovea nasal regions (ρ = - 0.356, p = 0.007) in the DCP flow area. CPD was found to be lower in the macula, while similar in the fundus region in axSpA patients compared to HCs. The decrease in CPD was correlated with disease duration, but not with disease activity in axSpA. Small vessel structures may be affected in axSpA. OCT-A may be used to detect subclinical vasculitis in axSpA patients.

Optical coherence tomography angiography findings in young ß-thalassemia patients.

PURPOSE: The purpose was to evaluate retinal vascular parameters by optical coherence tomography angiography in ß-thalassemia major patients. METHODS: Thirty-three patients with ß-thalassemia major (study group) and 29 healthy children (control group) were enrolled in the study. All subjects underwent a complete ocular examination. The mean foveal avascular zone, non-flow area, foveal avascular zone perimeter, acircularity index of foveal avascular zone, foveal density, the superficial capillary plexus, and deep capillary plexus were scanned using 6 × 6 mm optical coherence tomography angiography scans centered on the macula. Superficial capillary plexus and deep capillary plexus were also scanned centered on the optic disk. We collected data on histories of patients, and hemoglobin and ferritin were also studied from both groups. RESULTS: The mean age was 13.85 ± 4.69 years (range: 4-21 years) in ß-thalassemia major group and 12.59 ± 3.66 years (range: 6-18 years) in the control group. The mean foveal avascular zone value was 0.265 ± 0.11 mm2 in the study group and 0.296 ± 0.12 mm2 in the control group. The mean non-flow area value was 0.468 ± 0.12 mm2 in the study group and 0.479 ± 0.14 mm2 in the control group (p > 0.05). Differences in the mean values for foveal density and acircularity index were statistically significant between the study group and control group (p < 0.05, p = 0.026, and p = 0.026, respectively). Superficial capillary plexus and deep capillary plexus were not a significant difference between the study and control groups in 6 × 6 mm scans on macula and 4.5 × 4.5 mm scans on optic disk area (p > 0.05). Acircularity index was negatively correlated (r = -0.292, p = 0.026), and foveal density was positively correlated with hemoglobin (r = 0.292, p = 0.026). CONCLUSION: By using optical coherence tomography angiography, we detected foveal microvascular changes in young ß-thalassemia patients before significant ocular anomalies development.

Color Doppler imaging of ocular hemodynamic changes in patients with rheumatoid arthritis unrelated to disease activity.

We aimed to investigate how orbital blood flow rates in patients with rheumatoid arthritis (RA) are affected by the active and remission phase of the disease. This prospective study included a total of 56 patients with RA (study group) and 24 control individuals (control group). All RA patients were divided into two groups, as active (Group 1) and remission (Group 2) according to the disease activity index (DAS 28) score. For each eye, retrobulbar vascular structures were evaluated [central retinal artery (CRA), posterior ciliary artery (PCA), and ophthalmic artery (OA)], respectively. The peak systolic velocity (PSV) and end-diastolic velocity (EDV) values were obtained for each artery and the vascular resistance index (RI) measurement was calculated. The median RI of the OA was 0.70 (0.57; 0.79) in the control group, 0.77 (0.55; 0.87) in group 1, and 0.73 (0.47; 0.87) in group 2. The median RI in the PCA was 0.70 (0.56; 0.82) in the control group, 0.76 (0.52; 0.88) in the group 1, and 0.74 (0.52; 0.86) in the group 2. The median RI of CRA was 0.73 (0.48; 0.81) in the control group, 0.71 (0.64; 0.81) in group 1, and 0.68 (0.61; 0.85) in group 2. The RI value was a significant difference between control and group 1 (p < 0.05). Active and remission RA patients had different effects on the flow rate of eye blood vessels.

A simple and efficient method for cultivation of limbal explant stem cells with clinically safe potential.

BACKGROUND: Several methods to cultivate limbal epithelial stem cells (LESCs) in vitro with the support of feeder layers and different growth medium formulations have been established for several years. The initial green medium consists of various ingredients that exhibit a non-optimal level of biosafety, therefore, different modifications have been made to suit it to safe clinical applications. However, the question of which formulation is the most appropriate remains to be answered. AIMS: This study evaluated the outgrowth kinetics and stemness of cells cultured from human limbal explants with the aim of preserving LESC characteristics in the human-derived platelet-rich fibrin (HPRF)-conditioned medium with no feeder cell layer or carrier for the first time. The final composition of the cell culture system included only human-derived products without any xenobiotic or chemical substances to minimize the potential risk for human health, which will be useful for clinical purposes. METHODS: To test our hypothesis, limbal explants were incubated with either Dulbecco's Modified Eagle's Medium (DMEM)/F12-10% human serum (HS), human-derived amniotic membrane (HAM)-conditioned DMEM/F12-10% HS or HPRF-conditioned DMEM/F12-10% HS to determine whether outgrowth kinetics and stemness of cells show any differences among groups. RESULTS: The results showed that the HPRF-conditioned medium showed higher concentration levels of growth factors, which may be involved in the promotion of LESC expansion while preserving the stem cell characteristics. HPRF-conditioned medium had significantly superior capacity to enhance the cell growth rate, the stem/progenitor cell phenotype and the expressions of putative stem cell markers. CONCLUSION: This novel xeno-feeder-chemical-free, completely human-derived and biologically safe culture system including HPRF and HS would be of interest to replace conventional cell culture strategies to meet safety requirements mandatory for clinical use in humans.

An assessment of ocular elasticity using real time ultrasound and ocular response analyzer in active or remission rheumatoid arthritis.

PURPOSE: To investigate the elasticity of ocular structures in patients with rheumatoid arthritis (RA) without ocular involvement. METHODS: The study included 56 RA patients (study group) and 24 healthy volunteers as the control group. The rheumatoid arthritis patients were divided into two subgroups as those in active phase (Group 1, n = 25) or in remission phase (Group 2, n = 31) according to the disease activity index (DAS 28) score. The elastography values of the ratio of orbital fat-sclera (ROF/S) were measured with real-time US elastography, and corneal mechanical values were measured with the Reichert Ocular Response Analyzer in each eye. RESULTS: The mean ROF/S value was 5.2 ± 1.8 in Group 1, 0.7 ± 0.4 Group 2, and 0.6 ± 0.1 in the control group. There was a significant difference between the Group 1 and control group with regard to ROF/S (p < 0.001), but no significant difference was determined between Group 2 and control group (p > 0.05). The mean ROF/S value was a significant difference between the Group 1 and 2 (p < 0.001). ROF/S was significantly correlated with DAS-28 and C-reactive protein (CRP) (r = 0.816, p < 0.001 and r = 0.259, p = 0.006). CONCLUSIONS: ROF/S was significantly increased in patients in the active phase of RA. Findings revealed that ocular tissue structural changes may occur in the active phase and these could be related to ocular complications as a prognostic factor.

A completely human-derived biomaterial mimicking limbal niche: Platelet-rich fibrin gel.

Platelet-rich fibrin (PRF) is a natural biomaterial and has excellent biochemical and physical properties with a history of proven biocompatibility in the field of tissue engineering and regenerative medicine. Recent reports of fibrin-based matrices have offered new opportunities to apply PRF as a supplement for in vitro cell culture. Here, custom-modified human-derived PRF (HPRF) was produced via different centrifugation protocols, then, characterized by morphologically and chemically and utilized as a substrate and as a conditioned medium for limbal explant culture for the first time. It was found that the HPRF released significantly higher levels of growth factors which are essential for epithelial cell growth. The enhanced physicochemical properties of the HPRF were also proven in the limbal explant cultures in terms of cell growth, migration, viability, and stemness in comparison with the conventional limbal explant culture on human-derived amniotic membrane. Consequently, HPRF hydrogels are appealing natural biomaterials for the purpose of mimicking limbal niche and the discovery elucidates this new, xeno-chemical-free, completely human-derived biomaterial can be utilized as a supplement to promote epithelial cell behaviour in vitro.

The association of Helicobacter pylori with choroidal and retinal nerve fiber layer thickness.

PURPOSE: To investigate the effect of Helicobacter pylori (H. pylori) infection on choroidal thickness (CT) and retinal nerve fiber layer thickness (RNFLT). METHODS: The study included 25 patients with H. pylori infection and 25 healthy individuals as the control group. Helicobacter pylori patients were classified as the pre-treatment (Group 1; n: 25) and the post-treatment (Group 2; n: 25). RNFLT and CT were measured before and after treatment of H. pylori infection, using enhanced depth imaging (EDI) spectral-domain optical coherence tomography (Spectralis, Heidelberg Engineering, Heidelberg, Germany). The axial length and intraocular pressure were also measured. RESULTS: The mean subfoveal CT was 320.96 ± 29.15 µm in Group 1 and 287.48 ± 49.17 in the control group (p = 0.007), while the mean subfoveal CT did not show any difference between Group 2 and the control group (p > 0.05). No statistically significant difference was determined between the H. pylori patients and the control group in respect of RNFLT values (p > 0.05). CONCLUSIONS: CT increases during H. pylori infection and returns to the normal range within 6 weeks of treatment. RNFLT does not show any change during H. pylori infection. The data related to the subfoveal CT may be useful in understanding the pathogenesis of central serous chorioretinopathy developing in H. pylori patients.

Choroidal Thickness in Childhood Obesity.

BACKGROUND AND OBJECTIVE: To evaluate the effects of obesity on choroidal thickness (CT) in childhood. PATIENTS AND METHODS: Forty-four patients with obesity (study group) and 42 healthy children (control group) were enrolled in the study. Subjects underwent a complete ocular examination. The mean CT was measured by enhanced depth imaging optical coherence tomography (EDI-OCT). Body mass index (BMI) was calculated. RESULTS: Mean BMI value was 31.8 ± 1.9 in the study group and 19.8 ± 4.4 in the control group. The mean subfoveal CT value 385.77 µm ± 6.09 µm in the study group and 348.43 µm ± 73.21 µm in the control group. There was a significant difference between the study and control groups with regard to subfoveal CT (P = .017). Subfoveal CT and BMI were positively correlated (r = 0.288; P = .004). CONCLUSIONS: CT increases in childhood obesity. Findings revealed that adiposity causes a significant increase in CT, and it may be related to ocular complications. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:10-17.].

Increased Tear Film Osmolarity in Systemic Lupus Erythematosus.

PURPOSE: To evaluate tear film osmolarity in patients with systemic lupus erythematosus (SLE). METHODS: A total of 55 eyes from 55 patients with SLE and 47 eyes from 47 age- and gender-matched healthy individuals were included in this study. Tear film osmolarity was evaluated with a lab-on-a-chip technique (TearLab; TearLab Corporation, San Diego, CA) in SLE patients in comparison with healthy individuals, and results were correlated to clinically available diagnostic tests for dry eye, such as tear film break-up time (BUT), Schirmer's test, and Ocular Surface Disease Index (OSDI). RESULTS: The mean tear film osmolarity in the SLE patients and healthy individuals was 306.02 ± 13.27 mOsm/L and 300.74 ± 9.11 mOsm/L, respectively, which made for a statistically significant difference (p = 0.020). In the SLE group, tear film osmolarity was negatively correlated with the Schirmer's test score and the BUT value (r = -0.295 p = 0.029 and r = 0.347 p = 0.009, respectively), whereas tear film osmolarity was not correlated with OSDI score (r = -0.182 p = 0.183). CONCLUSIONS: This study revealed that tear film hyperosmolarity and abnormal tear film function are associated with SLE.

Outcomes of corneal collagen crosslinking using a customized epithelial debridement technique in keratoconic eyes with thin corneas.

The purpose of the study was to evaluate the outcomes and possible complications of CXL performed with customized epithelial debridement technique to keratoconic corneas with the thinnest pachymetry values less than 400 µm. Nineteen eyes of 19 patients were included. The uncorrected (UCVA) and best corrected visual acuity (BCVA), flattest and steepest keratometric (K) readings, central corneal thickness at the thinnest point (t-CCT), endothelial cell density (ECD) were assessed before and 12 months after CXL. The mean UCVA was increased (p = 0.001), while the mean BCVA did not show any difference (p > 0.05). The mean flattest and steepest K readings were decreased (p = 0.001). No change was observed in the mean t-CCT (p > 0.05). The mean ECD was decreased (p = 0.001). The mean pre-CXL and post-CXL percentages of polymegathism and pleomorphism did not show any significant difference (p > 0.05). CXL performed with customized epithelial debridement technique is successful in halting the progression of keratoconus in corneas thinner than 400 µm after 12 months of treatment. However, significant endothelial cell loss can occur after this procedure.

A Novel Technique for Conjunctivoplasty in a Rabbit Model: Platelet-Rich Fibrin Membrane Grafting.

Purpose. To investigate the effect of platelet-rich fibrin (PRF) membrane on wound healing. Methods. Twenty-four right eyes of 24 New Zealand rabbits equally divided into 2 groups for the study design. After the creation of 5 × 5 mm conjunctival damage, it was secured with PRF membrane, which was generated from the rabbit's whole blood samples in PRF membrane group, whereas damage was left unsutured in the control group. Three animals were sacrificed in each group on the 1st, 3rd, 7th, and 28th postoperative days. Immunohistochemical (IHC) stainings and biomicroscopic evaluation were performed and compared between groups. Results. PRF membrane generated significant expressions of vascular endothelial growth factor (VEGF), transforming growth factor-beta (TGF-ß), and platelet-derived growth factor (PDGF) in the early postoperative period. However, the IHC evaluation allowed showing the excessive staining at day 28, in control group. Biomicroscopic evaluation revealed complete epithelialization in PRF membrane group, but none of the cases showed complete healing in the control group. Conclusions. This experimental study showed us the beneficial effects of the PRF membrane on conjunctival healing. Besides its chemical effects, it provides mechanical support as a scaffold for the migrating cells that are important for ocular surface regeneration. These overall results encourage us to apply autologous PRF membrane as a growth factor-enriched endogenous scaffold for ocular surface reconstruction.

Urgent Therapeutic Grafting of Platelet-Rich Fibrin Membrane in Descemetocele.

PURPOSE: To report the clinical and histopathological results of a novel autologous scaffold grafting, platelet-rich fibrin (PRF) membrane, in cases with descemetocele. METHODS: Three patients with severe corneal stromal melting and central descemetocele caused by neurotrophic keratopathy and infective keratitis underwent PRF membrane grafting on the central cornea for the prevention of imminent corneal perforation. After a quiescent 3-month period, penetrating keratoplasty and cataract extraction were performed for visual rehabilitation in 1 patient and host corneal tissue was examined histopathologically. RESULTS: Pain was significantly relieved, conjunctival inflammation was markedly resolved, and the central descemetocele area became thicker with scar formation in all patients. Histopathological examination revealed fibrosis formation over the descemetocele area without any tissue gap. Newly formed tissue containing irregular corneal lamellae covered the fibrosis formation and accounted for the prevention of perforation. CONCLUSIONS: Temporary PRF membrane grafting may be an alternative intervention to avoid impending corneal perforation in cases with severe descemetocele.