Automated evaluation of parapapillary choroidal microvasculature in crowded optic discs: a controlled, optical coherence tomography angiography study.

AIM: To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography (OCT-A). METHODS: Thirty patients with crowded discs, and 47 control subjects were enrolled in the study. One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm2 rectangular area. Radial peripapillary capillary (RPC) density, peripapillary retinal nerve fiber layer (pRNFL) thickness, cup volume, rim area, disc area, cup-to-disc (c/d) area ratio, and vertical c/d ratio were obtained automatically using device software. Automated parapapillary choroidal microvasculature (PPCMv) density was calculated using MATLAB software. When the vertical c/d ratio of the optic disc was absent or small cup, it was considered as a crowded disc. RESULTS: The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes (P=0.740). There was no difference in pRNFL between the two groups (P=0.102). There were no differences in RPC density in whole image (P=0.826) and peripapillary region (P=0.923), but inside disc RPC density was higher in crowded optic discs (P=0.003). The PPCMv density in the inner-hemisuperior region was also lower in crowded discs (P=0.026). The pRNFL thickness was positively correlated with peripapillary RPC density (r=0.498, P<0.001). The inside disc RPC density was negatively correlated with c/d area ratio (r=-0.341, P=0.002). CONCLUSION: The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs.

Comparison of optic disc head vascular density status between crowded and normal discs: An optical coherence tomography angiography study.

BACKGROUND: To compare the optic disc capillary vascular status between crowded and normal optic discs using optical coherence tomography angiography (OCT-A). METHODS: A total of 101 eyes were included in this cross-sectional, comparative study. Fifty-one eyes with crowded optic discs (Group 1) were compared with 50 eyes with normal discs (Group 2). Peripapillary and optic disc head capillary vascular density measurements were obtained quantitatively with OCT-A. RESULTS: Mean ages were 46.2 ± 6.2 years in Group1 and 45.9 ± 6.0 years in Group2 (p=0.796).Vertical disc diameters were 1.52±0.2 mm in Group 1 and 1.61±0.16 mm in Group 2 (p=0.022) whereas horizontal disc diameters were 1.53±0.17 mm in Group 1 and 1.61±0.13 mm in Group 2(p˂0.014). OCT-A findings were as follows: radial peripapillary capillary, vascular density whole image measurements (%); 49.6 ± 2.3 in Group 1 and 49.1 ± 2.3 in Group 2 (p=0.292), peripapillary capillary density; 53.3 ± 2.8 in Group 1 and 52.6 ± 2.6 in Group 2 (p=0.176), inside disc measurements 52.4 (48.7-54.7) in Group 1 and 46.5 (42.6-49.6) in Group 2 (p˂0.001). RNFL was 118.2 ± 12.2 µm in Group 1 and 110.8 ± 11.4 µm in Group 2(p=0.002). CONCLUSION: The vascular density of the disc circumference in individuals with healthy crowded optic discs is not different from those with normal discs. However, inside disc measurements differ between crowded and normal size discs. This finding suggests that when the disc size is reduced, the amount of vessels in it does not decrease in a way that correlates with the size. Therefore, the vascular structures are suitable for compression in the narrow optic nerve head.

Effect on ophthalmic imaging findings of flow-diverting stent treatment covering the origin of the ophthalmic artery.

BACKGROUND: Flow-diverting stents are devices that are increasingly used in the treatment of intracranial aneurysms and expand the spectrum of endovascular treatment. The patency of side branches and perforators is a major concern about flow-diverting stent (FDS) treatment. METHODS: From 2011 to 2020, seventy-eight patients in whom the orifice of the ophthalmic artery was covered during FDS treatment were evaluated in this study. Bilateral retinal vascular parameters of study subjects were evaluated with OCT and OCTA. The FDS implanted-side eyes of the patients were defined as the procedure group, and the fellow eyes were considered as the control group. RESULTS: Twenty-seven patients who were treated with FDS covering the ostium of the ophthalmic artery and who could undergo full ophthalmologic examination were included in the study. There was no statistically significant difference found in terms of visual acuity, retinal vascular parameters, and choroidal thickness between the procedure group and the control group (p>0.05). However, in one case, recanalized retinal artery branch occlusion was detected on the side where the FDS was implanted. CONCLUSION: The orifice of the ophthalmic artery is often covered during FDS treatment for carotid-ophthalmic aneurysms; however, this treatment approach has no significant effect on ophthalmic vascular parameters.

Predictive impact of optical coherence tomography biomarkers in anti-vascular endothelial growth factor resistant macular edema treated with dexamethasone implant.

PURPOSE: To perform a longitudinal analysis of the effect of optic coherence tomography (OCT) biomarkers on macular thickness in patients with persistent macular edema secondary to diabetes mellitus and retinal vein occlusion who recieved intravitreal dexamethasone (DEX) implant. METHODS: Eighty-nine patients were included in the retrospective study. Patients with anti-VEGF-resistant macular edema were included in the study. The effect of the presence or absence of OCT biomarkers before intravitreal DEX implant therapy on central foveal thickness (CFT) was evaluated. In addition, the change in biomarkers from the baseline visit to the final visit was evaluated. The evaluated OCT biomarkers were as follows: ellipsoid zone and external limiting membrane (ELM) integrity, hyperreflective foci (HRF), disorganization of inner retinal layers (DRIL), hard exudates, serous macular detachment (SMD), pearl necklace, posterior vitreous detachment and the epiretinal membrane (ERM). RESULTS: The mean age of the overall sample in the study was 64.4 ± 9.6. CFT decreased significantly from 625.3 ± 22.3 µm at baseline to 365.0 ± 21.7 µm in the 1st month but increased significantly to 430.2 ± 22.6 µm in the 3rd month. In the presence of HRF and SMD, recurrence of macular edema was significant in the 3rd month. The percentage of ELM disruption, DRIL, and ERM deteriorated significantly and the percentage of SMD improved significantly at the final visit. CONCLUSIONS: DEX implant therapy resulted in a satisfactory reduction in CFT in patients with DME and RVO. The presence of HRF and SMD is a negative predictor of recurrence in CFT in short term. DEX implant therapy resulted in satisfactory improvement in SMD.

The Effect of Corticosteroid Therapy on Choroidal Thickness in Patients With Covid-19 Infection: A Prospective, Comparative, and Observational Study.

BACKGROUND: Coronavirus disease 2019 (Covid-19) has many different ocular manifestations. This study evaluates the effects of the disease and the steroid used in this disease on ocular structures. PURPOSE:  To evaluate the effects of Covid-19 and the steroids used in the treatment of severe infection on ocular structures and choroidal thickness. METHODS: This prospective study included 76 eyes of 76 patients who were hospitalized due to Covid-19 and 30 eyes of 30 healthy volunteering controls. Group I included 35 eyes who were hospitalized due to moderate-to-severe involvement that received steroid treatment, group II included 41 eyes with moderate involvement that did not require steroid treatment, and group III included 30 eyes with age- and gender-matched control subjects. Ophthalmological examination and imaging results of the patients obtained in the third week and third month after the diagnosis were compared between the groups. RESULTS: Mean age of all participants was 40.2 ± 6.1 years. In the third week after the diagnosis of Covid-19, choroidal thickness in all regions (subfoveal, nasal, and temporal) was significantly greater in group I than in group II (for all, p<0.001). Moreover, choroidal thicknesses were significantly higher in group I and group II than in the control group (for all, p<0.001). In the third month, all the groups had similar choroidal thickness values (for subfoveal, nasal, and temporal; p=0.058, p=0.111, p=0.079, respectively). CONCLUSION: Our findings showed that Covid-19 infection causes choroidal thickening by affecting the choroidal layer and that steroid treatment further increases this thickness in the acute period. In addition, the reversal of this thickening to the normal level within a period of three months indicates that the effect of the disease on the choroid is reversible.