Optical coherence tomography angiography biomarkers of microvascular alterations in RVCL-S.

Background: The brain and retina share many neuronal and vasculature characteristics. We investigated the retinal microvasculature in patients with a monogenic vasculopathy using optical coherence tomography angiography (OCTA). OCT-A is a novel precise non-invasive imaging method that may provide biomarkers suitable for diagnosis and follow-up of small vessel diseases. Methods: In this exploratory cross-sectional study, eleven RVCL-S patients and eleven age-matched healthy control participants were included. The size of the foveal avascular zone (FAZ) and the vascular density of the superficial capillary networks in the retina were measured by OCT-A. Results: The symptomatic and presymptomatic patients showed significantly lower vascular density values than controls in the foveal region [median (IQR) 18.2% (15.8-18.6) vs. 24.4% (21.5-26.8) (p < 0.001), 29.8% (29.6-30.8) vs. 33.2% (32.0-33.6) (p = 0.002), respectively]. The FAZ was significantly larger in the symptomatic RVCL-S patients than in the control group [13,416 square pixels [7,529-22,860] vs. 1,405 square pixels [1,344-2,470] (p < 0.001)]. No significant difference was identified in measurements of FAZ comparing presymptomatic and controls. Conclusion: Our findings with OCT-A demonstrated that RVCL-S causes an increase in the size of the FAZ in symptomatic RVCL-S patients compared to healthy participants. Moreover, there is a decrease in vessel density in the superficial capillary networks in both symptomatic and presymptomatic patients. In the future, newly developed precise objective instruments such as OCT (-A) may provide important tools in determining disease activity for follow up of common small vessel diseases.

Spectral Domain Optical Coherence Tomography in Retinal Vasculopathy With Cerebral Leukoencephalopathy and Systemic Manifestations: A Monogenic Small Vessel Disease.

BACKGROUND: Retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) is a monogenic small vessel disease caused by mutations in TREX1. Several organs, including retina and brain, are affected. Analyzing retinal anatomy is increasingly used as a biomarker for ophthalmological and neurological disorders (due to the shared embryological origin of retina and brain). Optical coherence tomography (OCT) provides a noninvasive cross-sectional visualization of optic disc and macula. We aimed to use OCT to investigate retinal layer thickness in RVCL-S. METHODS: Cross-sectional, 17 TREX1 mutation carriers (34 eyes) and 9 controls (18 eyes) underwent comprehensive ophthalmologic assessment followed by spectral domain OCT for measuring peripapillary retinal nerve fiber layer (pRNFL) thickness and total macular volume (TMV). Secondary outcomes included measuring thickness of individual macular retinal layers and peripapillary sectors. Findings were analyzed using generalized estimating equations to account for intereye correlation. RESULTS: TREX1 mutation carriers had decreased pRNFL thickness (median [interquartile range] 76 [60-99] vs 99 [87-108] µm, P < 0.001) and TMV (8.1 [7.4-8.5] vs 8.7 [8.4-8.8] mm3, P = 0.006) compared with controls. With the exception of the temporal sector, the thickness of all peripapillary sectors was decreased in TREX1 mutation carriers. Ganglion cell layer (30 [22-37] vs 39 [36-41] µm, P < 0.001) and inner plexiform layer (27 [24-34] vs 34 [31-35], P = 0.001) were thinner in TREX1 mutation carriers. Notably, in 9 of 12 eyes with normal funduscopic examination, retinal thinning was already detected. CONCLUSIONS: RVCL-S, which may serve as a vascular retinopathy model, is associated with retinal thinning in the peripapillary and macular area. OCT findings can potentially serve as early biomarkers for RVCL-S and other vascular retinopathies.

The association of the blastomere volume index (BVI), the blastomere symmetry index (BSI) and the mean ovality (MO) with ongoing implantation after single embryo transfer.

PURPOSE: To generate novel, objective variables that resemble embryo quality and relate them to ongoing implantation, using multilevel imaging of single-transferred embryos. METHODS: Retrospective analysis of multilevel images of 659 day 3 single-transferred embryos. Each embryo was photographed on seven different levels, in order to measure the largest diameter of every blastomere within an embryo. The volume of each blastomere was calculated using the equation [Formula: see text]. The blastomere volume index (BVI) represented the ratio between the total blastomeric volume of an embryo and the mean cytoplasmic volume of an oocyte on day 0. The blastomere symmetry index (BSI) represented the ratio between the greatest blastomere volume and the smallest blastomere volume within an embryo. The mean ovality (MO) represented the presence of non-spherical blastomeres. Analyses were performed to compare the BVI, BSI and MO between patients with and without an ongoing implantation. RESULTS: The mean BVI was significantly higher for embryos in the ongoing implantation group compared to the no ongoing implantation group. The mean BSI was associated with ongoing implantation for unevenly cleaved embryos. The MO of blastomeres within an embryo was similar for embryos in the ongoing implantation group compared to the no ongoing implantation group. The association of the BVI and BSI with ongoing implantation was confounded, because only female age and cleavage rate were significantly associated with ongoing implantation in multiple logistic regression analyses. CONCLUSIONS: The BVI, BSI and MO are objective variables that resemble embryo quality, but they are not suitable to use as embryo selection tools.