Association between Choroidal Thickness and Ocular Perfusion Pressure in Young, Healthy Subjects: Enhanced Depth Imaging Optical Coherence Tomography Study

Kurysheva N.I., Ponomareva S.I., Maslova E.V., Kim V.E., Rodionova O.Y., Pomerantsev A.L.

Glaucoma, one of the leading causes of blindness, often develops asymptomatically, necessitating early diagnosis and prediction of the progression rate of glaucomatous optic neuropathy (GON). Purpose. To develop a classification model using machine learning methods for predicting the rate of GON progression, and to identify the most significant predictors of progression in patients with newly diagnosed early primary open-angle glaucoma (POAG). Material and methods. The study included 59 patients (59 eyes) with early POAG, categorized into three groups based on the expert assessment of GON progression rate over a 36-month follow-up using dynamic morphofunctional evaluation. A classification model incorporating 35 clinical parameters, including optical coherence tomography (OCT) and OCT-angiography (OCT-A) data, was developed using partial least squares discriminant analysis (PLS-DA). Results. Over the 36-month follow-up, slow GON progression was recorded in 21 patients, moderate in 18, and rapid in 20. The mean progression rates were −0.77±1.27%/year for visual field area, −1.21±1.48 µm/year for retinal nerve fiber layer (RNFL) thickness, and −1.23±1.77 µm/year for ganglion cell complex (GCC) thickness. The model demonstrated sensitivity of 90%, specificity of 95%, and efficiency of 92%. The most significant predictors of GON progression were mean vessel density in the deep vascular plexus of the macular region (wiVD_Deep), choriocapillaris dropout in the inferior-nasal peripapillary region, choroidal thickness in the fovea, and lamina cribrosa thickness. Conclusion. The developed model effectively classifies patients based on the predicted progression rate of GON, which is important for individualized approach to glaucoma treatment planning.

Hammer M., Ie A., Eibenberger K., Auffarth G.U., Xue K.

Abstract Purpose Proliferative vitreoretinopathy (PVR) is a complication of retinal detachment which requires multiple vitreoretinal surgical interventions and frequent use of oil endotamponade. In this study, we conducted an in-depth analysis of complications associated with the use of heavy silicone oil in the management of inferior PVR. Methods A retrospective cohort study of 20 eyes that underwent vitrectomy for inferior PVR with use of heavy silicone oil (Densiron 68) between March 2021 and October 2022 at Oxford Eye Hospital. Complications were classified into major categories relating to intraocular pressure, inflammation, lens, and oil emulsification/migration. Visual outcomes and surgical success rate were also evaluated. Results Fill-induced pressure spikes (> 30 mmHg) within 14 days post-surgery were common after Densiron tamponade, especially in patients previously on glaucoma drops. The number of glaucoma drugs were increased in 45% of patients during Densiron tamponade. In 20% of cases, an increased medication was continued long-term after Densiron removal. Significant cataract progression occurred in all phakic patients. In 25% of pseudophakic cases, posterior capsule opacification was noted. Inflammatory complications, such as anterior uveitis, were rare and any cystoid macular oedema was transient. No unexplained acute loss of vision following Densiron removal was encountered. The anatomical success rate at 30 days after Densiron removal was 70%. The mean (± SD) best-corrected visual acuities were 1.04 (± 0.79), 0.85 (± 0.62) and 0.50 (± 0.51) logMAR prior, during and after Densiron tamponade, respectively. Conclusion The outcomes in this cohort treated with Densiron 68 were comparable to previously reported anatomical and functional results in cases with inferior PVR. IOP and lens-related complications require additional treatment during or after Densiron tamponade. Inflammatory complications rarely occurred over tamponade durations of around three months. Trial registration Analyses were conducted as an internal quality improvement audit and as such did not require external IRB review.

Kong K., Liu X., Fang Z., Jiang J., Jiang J., Wang D., Yang Z., Zhou F., Chen E.M., Liang J., Song Y., Lin F., Ohno-Matsui K., Jonas J.B., Han Y., et. al.

Axial elongation continues in highly myopic adult eyes, even in the absence of pathologic changes such as posterior staphyloma or chorioretinal atrophy. This ongoing axial elongation leads to structural changes in the macular and peripapillary regions, including chorioretinal thinning, reduced vascular perfusion and optic disc tilting and rotation, among others. These alterations can affect the acquisition and interpretation of optical coherence tomography, optical coherence tomography angiography and fundus photographs, potentially introducing artifacts and diminishing the accuracy of glaucoma diagnosis in highly myopic eyes. In this review, we compared the progression patterns of axial elongation across populations with varying demographic characteristics, genetic and environmental backgrounds and ocular features. We also discussed the implications of axial elongation-induced ocular structural changes for diagnosing glaucoma in nonpathologic high myopia. Finally, we highlighted the prospects for enhancing the diagnostic efficacy of glaucoma in nonpathologic highly myopic populations.

Monferrer-Adsuara C., Remolí-Sargues L., Navarro-Palop C., Cervera-Taulet E., Montero-Hernández J., Medina-Bessó P., Castro-Navarro V.

Purpose Ocular ischemic syndrome can be the first and only hint of life-threatening carotid artery disease. The early recognition of carotid stenosis-related retinal signs, as well as the comprehension of the pathophysiology behind retinal changes could become relevant for physicians to predict the risk of stroke. The aim of this study is to assess the carotid artery disease-induced early structural retinochoroidal changes by means of swept-source optical coherence tomography (SS-OCT). Methods A prospective observational study was conducted in 72 eyes with carotid stenosis. According to the degree of stenosis, the participants were divided into a normal group (34 eyes), a mild-moderate stenosis group (22 eyes), a severe stenosis group (16 eyes). SS-OCT and OCTA were performed to scan macular fovea. Central macular thickness (CMT), subfoveal choroidal thickness (SCT) and foveal avascular zona (FAZ) area were the major measurements for our study. Results CMT was significantly thicker in group 3 when compared to group 2 and 1. SCT was significantly thinner in group 3 vs group 1, being thicker in group 2 when compared to group 1. No significant differences were obtained when comparing FAZ in the superficial and middle capillary plexus although it was significant when comparing the FAZ in the deep capillary plexus between group 1 and 3. Conclusion internal carotid artery stenosis greater than 70% leads to a significant increase in CMT and a decrease in SCT prior the development of clinical findings of ocular ischemia syndrome.

Khanal S., Turnbull P.R., Kim L., Phillips J.R.

Zamorano Aleixandre M., Redondo Marcos I., González-López J.J.

Systemic sclerosis is a chronic, autoimmune, multisystem disease characterized by vascular dysfunction, chronic inflammation and widespread fibrosis. Although vascular involvement commonly manifests in the skin, it can also affect other organs, including the eyes. The characteristic vascular alteration is an obliterative fibroproliferative vasculopathy leading to hypoxia and tissue ischemia. We present a case of bilateral macular edema in a patient diagnosed with systemic sclerosis, as a consequence of retinal and choroidal vascular changes. La esclerosis sistémica (ES) es una enfermedad crónica, autoinmune y multisistémica que se caracteriza por una disfunción vascular, inflamación crónica y fibrosis generalizada. Aunque la afectación vascular se manifiesta comúnmente en la piel, también puede afectar otros órganos, incluyendo los ojos. La alteración vascular característica es una vasculopatía fibroproliferativa obliterante que conduce a la hipoxia e isquemia tisular. Presentamos un caso de edema macular (EM) bilateral en una paciente diagnosticada de ES como consecuencia de cambios vasculares retinianos y coroideos.

Zamorano Aleixandre M., Redondo Marcos I., González-López J.J.

La esclerosis sistémica (ES) es una enfermedad crónica, autoinmune y multisistémica que se caracteriza por una disfunción vascular, inflamación crónica y fibrosis generalizada. Aunque la afectación vascular se manifiesta comúnmente en la piel, también puede afectar otros órganos, incluyendo los ojos. La alteración vascular característica es una vasculopatía fibroproliferativa obliterante que conduce a la hipoxia e isquemia tisular. Presentamos un caso de edema macular (EM) bilateral en una paciente diagnosticada de ES como consecuencia de cambios vasculares retinianos y coroideos. Systemic sclerosis is a chronic, autoimmune, multisystem disease characterized by vascular dysfunction, chronic inflammation and widespread fibrosis. Although vascular involvement commonly manifests in the skin, it can also affect other organs, including the eyes. The characteristic vascular alteration is an obliterative fibroproliferative vasculopathy leading to hypoxia and tissue ischemia. We present a case of bilateral macular edema in a patient diagnosed with systemic sclerosis, as a consequence of retinal and choroidal vascular changes.

Baksh J., Lee D., Mori K., Zhang Y., Torii H., Jeong H., Hou J., Negishi K., Tsubota K., Kurihara T.

Myopia is a common refractive error that affects a large proportion of the population. Recent studies have revealed that alterations in choroidal thickness (ChT) and choroidal blood flow (ChBF) play important roles in the progression of myopia. Reduced ChBF could affect scleral cellular matrix remodeling, which leads to axial elongation and further myopia progression. As ChT and ChBF could be used as potential biomarkers for the progression of myopia, several recent myopia treatments have targeted alterations in ChT and ChBF. Our review provides a comprehensive overview of the recent literature review on the relationship between ChBF and myopia. We also highlight the importance of ChT and ChBF in the progression of myopia and the potential of ChT as an important biomarker for myopia progression. This summary has significant implications for the development of novel strategies for preventing and treating myopia.

Li S., Zhao W., Jian T., Xu F., Li Z., Yang X., Wang S., Wu W., Wang J., Lou J., Jianqiao L.

To investigate the alterations in retinochoroidal parameters measured by optical coherence tomography (OCT) and OCT angiography (OCTA) in patients with carotid artery stenosis (CAS) and assess their associations with digital subtraction angiography (DSA) data. This study enrolled patients diagnosed with CAS and age-matched healthy controls. Both groups underwent OCT and OCTA examinations. DSA and assessment of carotid artery stenosis were performed only in the CAS group. The study evaluated various retinochoroidal parameters from OCT and OCTA, including linear vessel density (LVD), foveal avascular zone (FAZ), choroidal thickness (ChT), and retinal nerve fiber layer (RNFL) thickness. DSA-derived measures included cervical segment (C1) diameter, cavernous segment (C4) diameter, stenosis percentage, ophthalmic artery (OA) filling time, C1-OA filling time, and residual stenosis. A total of 42 eyes from 30 CAS patients and 60 eyes from 30 healthy controls were included. Patients with CAS displayed significantly decreased LVD compared to controls (p < 0.001). Additionally, the CAS group had thinner choroid and RNFL (p = 0.047 and p < 0.001, respectively). Macular LVD negatively correlated with both stenosis percentage and C1-OA filling time (p = 0.010 and p = 0.014, respectively). In patients who underwent carotid artery stenting, preoperative ChT significantly correlated with residual stenosis (Pearson r = -0.480, p = 0.020). OCT and OCTA provide a quantitative assessment of retinochoroidal microstructural changes associated with CAS, suggesting potential for noninvasive evaluation of the disease. This might contribute to the prevention of irreversible ocular complications and early detection of CAS. Furthermore, ChT may not only aid in diagnosing CAS more reliably but also offer prognostic information.

Aznabaev B., Mukhamadeev T., Ismagilov T., Dibaev T.

Reduction of the adverse effects of intraoperative intraocular pressure fluctuation referred to as post-occlusion surge on the intraocular structures is an important task for ensuring phacoemulsification safety. In this regard, the method to control infusion during phacoemulsification based on controlling the infusion and aspiration flow rates in combination with monitoring of vacuum parameters was developed. The study was aimed to provide comparative assessment of clinical and functional characteristics of the eye in patients after phacoemulsification using the new and already existing adaptive infusion control methods. A total of 38 patients aged 66.4 ± 7.8 years (15 males and 23 females) in the index group (Optimed Profi system with the use of new method) and 35 patients aged 68.7 ± 7.5 years (16 males and 19 females) in the control group (Centurion Vision System with Active Fluidics) underwent surgery due to cataract. The patients underwent comprehensive eye examination before surgery and on days 1, 7, 30, months 3, 6 after surgery. The smaller loss of corneal endothelial cells on months 3 and 6 after surgery was observed in patients of the index group with grade III and IV cataract (p < 0.05). Comparison of macular microcirculation parameters revealed the reduced FAZ area by month 6 of postoperative follow-up in the index group, along with the increased total vascular density of the deep vasculature (p < 0.001). A significant decrease in the total density of the superficial and deep vascular plexuses by month 6 of postoperative follow-up was observed in the control group (p < 0.05). The use of new adaptive infusion control method contributes to effective phacoemulsification of cataracts of varying density with the lower percentage of the corneal endothelial cells lost in the late postoperative period.

Guo T., Jin Y., Zhou M., Lei B., Huang L., Chen S., Xue K.

To evaluate changes in retinal and choroidal vascularity using swept-source optical coherence tomography (SS-OCT) and optical coherence tomography angiography (OCTA) in patients with systemic lupus erythematosus (SLE). In this prospective, cross-sectional study, 48 SLE patients and 40 healthy control (group HC) participants were included. The SLE patients were divided into two subgroups: patients with SLE with no ocular disease (group I) and patients with SLE with signs of retinopathy (group II). The superficial vessel density (SVD), deep vessel density (DVD), peripapillary retinal vessel densities (pRVD), choroidal thickness (ChT), and choroidal vascularity including total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI) were measured using SS-OCT/OCTA. Physical and ophthalmic examinations as well as the assessments of immunological markers were performed. The results of SS-OCT/OCTA were compared between group I, group II, and group HC, while the correlations among the parameters were analyzed. The SVD, DVD, and pRVD were found to be significantly lower in SLE patients than group HC, especially in SLE patients with signs of retinopathy. ChT were found to be significantly higher in group II. CVI was positively correlated with SVD and DVD in the fovea, as well as the foveal and parafoveal thickness. A significant decrease in SVD and DVD in the fovea among subjects positive for anti-dsDNA antibodies was noted. The application of OCTA in the evaluation of microvasculature may be useful in subclinical changes. Retinal microvascular density decreased in patients with SLE with greater severity of SLE. Disturbed retinal circulation was related to SLE disease activity, disease duration, CVI, and being positive for anti-dsDNA antibodies. The study results also suggest that SLE with signs of retinopathy may affect the choroid with increases in LA, SA, TCA, and ChT.

Yu M., Sun X., Zeng F., Gao X., Li Z., Yuan G., Wang T.

Abstract Background To investigate the short-term effects of blood donation on the morphology and blood flow of the retina and choroid in healthy people using optical coherence tomography angiography (OCTA). Methods Twenty-eight healthy blood donors (56 eyes) who participated in the 200 ml voluntary blood donation between March 2, 2021 and January 20, 2022 were included. The best corrected visual acuity (BCVA), systolic (SBP) and diastolic blood pressure (DBP), intraocular pressure (IOP), subfoveal choroid thickness (SFCT), retinal thickness (RT), retinal superficial vascular density (SVD), deep vascular density (DVD) and foveal avascular were a (FAZ) were measured and statistically analysed 10 min before, 30 min and 24 h after the blood donation. Results The 200 ml blood donation could cause significant IOP reduction at 24 h (P = 0.006), which was negatively correlated with SBP (r = -0.268, P = 0.046), while SBP, DBP, or ocular perfusion pressure were not affected (> 0.05). Moreover, no significant difference existed in the OCT and OCTA indexes, including SFCT, RT, SVD, DVD, and FAZ, before and after the 200 ml blood donation (P > 0.05). The visual acuity was not affected either (P > 0.05). Conclusions The 200 ml blood donation was noted to be associated with statistically significant IOP reduction at 24 h, while SBP, DBP, or OPP was not affected. The blood flow of the retina and choroid or the visual acuity did not change significantly after the blood donation. Larger studies with different volumes of blood donation were needed to further analysis the effect of blood donation on ocular parameters.

Hirano M., Muraoka Y., Kogo T., Ishikura M., Nishigori N., Ueda-Arakawa N., Miyata M., Hata M., Takahashi A., Miyake M., Tsujikawa A.

Abstract We aimed to obtain widefield (WF) swept source optical coherence tomography (SS-OCT) data and examine the features of choroidal thickness maps of healthy eyes. The posterior pole choroidal thickness was examined for 127 eyes using enhanced-depth imaging (EDI) of SS-OCT with a viewing angle of 20 (vertical) × 23 (horizontal) mm, and choroidal thickness maps were generated. For SS-OCT image analysis, we developed a grid with inner and outer rings, each divided into superotemporal, inferotemporal, superonasal, and inferonasal quadrants, respectively, making up a total of nine subfields including the central 3-mm ring. The posterior pole choroidal thicknesses were significantly lesser at the periphery than in the central area, in the inferior field than in the superior field, and in the nasal field than in the temporal field (p < 0.001 for all). We also evaluated the effects of age and axial length (AL) on the WF choroidal thickness. Choroidal thicknesses in all subfields were negatively associated with advanced age (p < 0.05). Choroidal thicknesses in the central subfield and the inferonasal inner and outer subfields were negatively associated with AL (p = 0.042, 0.034, and 0.022, respectively). These findings provide insights into the two-dimensional characteristics of the choroidal thickness and their associations with age and AL.

Lin L., Zhang X., Huang C., Zhang Z.

Background Myopia is the most common ophthalmic condition worldwide with a rapidly increasing prevalence. This study aimed to compare the retinal microvasculature in the superficial capillary plexus (SCP) in children and adolescents with mild and moderate/high myopia using optical coherence tomography angiography, determine the relationship between retinal parameters and axial length (AL), and understand the occurrence and progression of myopia in microcirculation. Methods This prospective observational study included 39 participants with mild myopia and 33 participants with moderate/high myopia. Vessel density (VD) and perfusion density (PD) in the SCP, the foveal avascular zone (FAZ), and AL were compared between the groups and the relationship between these retinal parameters and AL was assessed. Results No difference in SCP VD or PD was observed between the two groups. The FAZ did not differ significantly between groups whereas significant differences in age, height, refractive status, and AL were observed. Significantly shorter AL was observed in participants with mild myopia compared with the moderate/high myopia group. Age was positively correlated with height (r = 0.852) and refractive status was negatively correlated with AL (r = −0.588). AL was positively correlated with VD (r = 0.317) and PD (r = 0.308) in the SCP and AL was negatively correlated with the FAZ (r = −0.434). Conclusions This study revealed that superficial foveal microvessel density was unaffected in children and adolescents without pathological myopia. However, myopia progression was associated with a change in AL, and an AL increase altered macular blood flow.

Tufek M., Nalcacioglu P., Capraz M., Varol K., Kaya A.T., Aydın N., Kara C.

Background: Obesity affects microvascular structures. The effect of obesity on the ocular vascular system can be evaluated by changes in the choroidal thickness (CT) and retrobulbar blood flow (RBF). Objectives: To evaluate the CT and RBF parameters in obese patients with various body mass index (BMI) values and compare these parameters with normal weight, healthy subjects. Design: A prospective study. Methods: The study included 102 eyes of 102 female patients. Patients were divided into three groups according to BMI as group 1 with a BMI of 18.5–24.99 ( n = 32), normal weight group; group 2 with a BMI of 30–34.99 ( n = 35), as obese class I; and group 3 with a BMI of 35–39.99 ( n = 35), as obese class II. The peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index, and pulsatility index values of the central retinal artery (CRA) and ophthalmic artery (OA) were evaluated with color Doppler ultrasonography. CT was measured at the subfoveal area and at 500-µm intervals nasal and temporal to the fovea up to a distance of 1500 µm by using the enhanced depth imaging technique of optical coherence tomography. Intraocular pressure (IOP) was measured with a Goldmann applanation tonometry. Results: There was a significant difference in IOP values within the groups with the highest values in group 3 (17.6 ± 2.1 mmHg) and the lowest in group 1 (12.4 ± 1.7 mmHg). The CT in groups 2 and 3 was found to be statistically significantly lower than that in group 1 at all measurement points ( p < 0.001). There was a statistically significant negative correlation between CT at all measurement points and BMI ( p < 0.001). The mean CRA PSV, EDV, and OA EDV values were statistically significantly lower in each obese group than those values in group 1 ( p < 0.001). The OA PSV values were significantly lower in group 3 (36.5 ± 5.9 cm/s) than those in group 2 (43.8 ± 4 cm/s) and group 1 (44.6 ± 5.2 cm/s) ( p < 0.001). Also, significant associations were found between BMI and CRA PSV, CRA EDV, and OA PSV values ( p < 0.001). Conclusion: Obesity may predispose to eye pathologies by changing the ocular vascular circulation.