Retinal Oxygen Saturation Correlates With Visual Acuity but Does Not Predict Outcome After Anti-VEGF Treatment in Central Retinal Vein Occlusion

Purpose Optic neuritis (ON) is an inflammatory demyelinating disorder of the optic nerve, which can be the first manifestation of multiple sclerosis (MS). The main goal was to assess changes in the retinal nerve fibre layer (RNFL) and in retinal oxygen saturation [arterial (AS), venous (VS) and arterio‐venous (A‐V) difference] in the affected and unaffected eye. Methods Fifty patients with ON due to MS within 3 months of onset of symptoms were enrolled (17 males, mean age 35.3). All patients were examined at baseline (V1) and after 6 months (V2) using optical coherence tomography (OCT) to get RNFL values; automatic retinal oximetry to obtain saturation values; and ultrasound to exclude arterial stenosis, and orbital colour Doppler imaging was performed in the ophthalmic artery. Results At V1, AS was significantly increased in affected eye compared to unaffected eye (99.5% versus 98.0%, p = 0.03). Significant decrease in A‐V difference from baseline was detected in both eyes for ON eye: 32.0% versus 29.0%, p = 0.004; for fellow eye: 31.4% versus 30.0%, p = 0.04. We did not observe any changes in retinal vessel diameter. There were no changes observed in blood flow in ophthalmic artery. At V1, there were no significant differences in RNFL, and significant loss of RNFL was confirmed in the affected eye at V2 (95 μm versus 86 μm, p = 0.0002) and in comparison with the fellow eye (86 μm versus 94 μm, p = 0.0002). There were no correlations between RNFL and saturation values at V1, although at V2, there was a negative correlation between the RNFL and AS (Spearman's rho = −0.480, p = 0.003) and between the RNFL and VS (rho = −0.620, p = 0.00007). Conclusion Retinal oximetry is altered in both eyes in MS patients with unilateral ON. During the course of the disease, the retinal oxygen consumption decreases to a different degree in each eye and this change is not completely followed by changes in the RNFL thickness, suggesting either sub‐clinical ON or systemic effects in the clinically unaffected eye. Since this is the first and initial longitudinal evaluation of the saturation changes in MS patients, the clinical value of these findings needs to be deeper evaluated in the future studies.

Section: Discussionsupporting

confidence: 76%

Changes in oxygen saturation and the retinal nerve fibre layer in patients with optic neuritis associated with multiple sclerosis in a 6‐month follow‐up

Svrčinová

Hok

Šínová

et al. 2020

“…It has been reported that retinal oxygen saturation before treatment did not contribute significantly to predicting visual outcome after three‐monthly intravitreal injections with VEGF inhibitor in central retinal vein occlusion (Jeppesen & Bek ). In DME patients, we found there was no significant correlation between VA improvement at 12 months and arterial oxygen saturation before treatment ( r = 0.291, p = 0.119; data not shown), or venous oxygen saturation before treatment ( r = 0.085, p = 0.656; data not shown).…”

Section: Discussionmentioning

confidence: 99%

Ranibizumab treatment improves diabetic macular oedema without influencing retinal oximetry parameters

Takasago

Fujita

Nakano

et al. 2019

Purpose: To evaluate the effect of ranibizumab on retinal oximetry in eyes with diabetic macular oedema (DME). Methods: In this prospective interventional study, 30 eyes (30 patients) with DME were treated with three-monthly intravitreal ranibizumab injections, followed by pro re nata administration for 12 months. Retinal oximetry was performed using an Oxymap T1. Results: The mean number of injections was 6.6 AE 2.5. No adverse event was observed throughout the study period. Ranibizumab treatments for 12 months improved the macular oedema (p = 0.002) and achieved a recovery of visual acuity (VA; p = 0.011). However, oxygen saturation levels in the major retinal blood vessels, either the arteries or the veins, remained unchanged during the observational period. Arterial oxygen saturation was 100.3 AE 9.4% before treatment and 100.9 AE 10.7% (p = 0.698) at 6 months. Venous oxygen saturation was 56.4 AE 8.9% before treatment and 55.6 AE 8.6% (p = 0.529) at 6 months. In addition, there were no significant changes in diameters of the major retinal arteries and veins. Greater improvement of VA at 12 months was correlated with a smaller number of ranibizumab injections (r = 0.459, p = 0.011). The number of ranibizumab injections during these 12 months correlated with an increased baseline central retinal thickness (r = 0.385, p = 0.035). Conclusion: Ranibizumab treatments for DME improved the macular oedema and achieved VA recovery, but no changes were noted in the retinal oxygen saturation.

“…; Blair et al. ), retinal vessel occlusions (Jeppesen & Bek ; Šínová et al. ) and glaucoma (Van Keer et al.…”

Section: Introductionmentioning

confidence: 99%

Retinal vessel oxygen saturation and vessel diameter in healthy individuals during high‐altitude exposure

Yang

Sun

et al. 2018

Purpose: To assess changes of retinal vessel oxygen saturation and vessel diameter in healthy individuals during high-altitude exposure. Methods: Retinal oxygen saturation and vessel diameter were obtained at sea level (SL, 40 m) and high altitude (HA, 3681 m) on 17 healthy individuals from Beijing (six males, 28.06 AE 8.06 years) using Oxymap T1 and then compared with 21 residents from Yushu (10 males, 28.63 AE 6.00 years). Systemic and ocular parameters were also measured before and after high-altitude exposure. Data were presented as mean AE SD and analysed using paired and independent Student t-test with significance accepted at p < 0.05. Results: Short-term high-altitude exposure of Beijing Group significantly affected all the systemic and ocular parameters, as well as retinal oxygen saturation and vessel diameter ranging from overall quadrant to different quadrants, other than retinal venous oxygen saturation and retinal arterial diameter. However, these changes were not evident in those permanently living at HA. Pearson's correlation analysis revealed correlations between retinal oxygen saturation and systemic and ocular parameters (all p < 0.05). The multivariate linear regression analysis indicated that retinal arterial oxygen saturation was significantly associated with arterial peripheral arterial oxygen saturation (SpO 2 ) and subfoveal choroidal thickness. Conclusion: Short-term exposure to HA induces retinal microcirculation disturbance and auto-regulatory response in healthy individuals, which is probably attributed to arterial SpO 2 and endothelial dysfunction under hypoxic conditions.