Alterations of the Foveal Avascular Zone Measured by Optical Coherence Tomography Angiography in Glaucoma Patients With Central Visual Field Defects

Citation: Kwon J, Choi J, Shin JW, Lee J, Kook MS. Alterations of the foveal avascular zone measured by optical coherence tomography angiography in glaucoma patients with central visual field defects. Invest Ophthalmol Vis Sci. 2017;58:163758: -164558: . DOI: 10.1167 PURPOSE. To investigate whether the area and shape of the foveal avascular zone (FAZ) as assessed by optical coherence tomography angiography (OCTA) are altered in glaucomatous eyes with central visual field defects (CVFDs). METHODS. A total of 78 patients with open-angle glaucoma with central or peripheral visual field defects (PVFDs) confined to a single hemifield were studied retrospectively. Foveal avascular zone area and circularity were measured using OCTA images from the superficial retinal layer. Central retinal visual field (VF) sensitivity using Swedish Interactive Threshold Algorithm 24-2 VF and macular ganglion cell-inner plexiform layer (mGCIPL) thickness were measured. The FAZ area between VF-affected hemimacular segments and VF-unaffected hemimacular segments in eyes with CVFDs and matched hemimacular segments of eyes with PVFDs were compared. Factors associated with the presence and severity of CVFD at initial presentation were determined. RESULTS. Eyes with CVFDs showed a significantly larger FAZ area, lower FAZ circularity, and lower mGCIPL thickness than the PVFD group. The mean hemi-FAZ area of VF-affected hemimaculas in eyes with CVFDs was significantly larger than that of the PVFD group (0.256 6 0.07 mm 2 vs. 0.184 6 0.07 mm 2 ) and the VF-unaffected hemimaculas of the CVFD group (0.179 6 0.06 mm 2 ; P < 0.05). Age, mean deviation, mGCIPL thickness, FAZ area, and circularity were associated with CVFDs (P < 0.05). CONCLUSIONS. Microcirculatory alterations in the perifovea are spatially correlated with central VF loss. Loss of FAZ circularity was significantly associated with presence of CVFD, whereas FAZ area was significantly associated with severity of CVFD. Keywords: foveal avascular zone, central visual field defects, optical coherence tomography angiography G laucoma is a leading cause of irreversible blindness and is characterized by progressive retinal ganglion cell (RGC) death and axonal loss. 1,2 Ocular blood flow (OBF) impairment and/or abnormal microcirculation along with elevated IOP may play an important role in glaucoma, particularly in normaltension glaucoma (NTG) 9,10 Optical coherence tomography angiography is a technique that uses differences between B-scans to generate contrasts associated with motion; in particular, the motion of blood cells through the vasculature. It identifies temporal changes in a specific location and recognizes them as erythrocyte motion. OCTA obtains detailed images of the macular microvascular networks with a high resolution and in a reproducible manner. 11 The foveal avascular zone (FAZ) is the round capillary-free zone within the macula. Manual measurement of FAZ area based on OCTA images at the superficial vascular network is a noninvasive, simple, and useful method for quantifying FAZ dimensions and architecture. 12,18-22 Foveal avascular zone circularity (roundness of the FAZ border) can also help characterize FAZ architecture, which can be reduced by vascular diseases in the macula, such as DR or retinal vein occlusion (RVO)

Single-Cell Transcriptomic Profiling of Pluripotent Stem Cell-Derived SCGB3A2+ Airway Epithelium.

Lung epithelial lineages have been difficult to maintain in pure form in vitro, and lineage-specific reporters have proven invaluable for monitoring their emergence from cultured pluripotent stem cells (PSCs). However, reporter constructs for tracking proximal airway lineages generated from PSCs have not been previously available, limiting the characterization of these cells. Here, we engineer mouse and human PSC lines carrying airway secretory lineage reporters that facilitate the tracking, purification, and profiling of this lung subtype. Through bulk and single-cell-based global transcriptomic profiling, we find PSC-derived airway secretory cells are susceptible to phenotypic plasticity exemplified by the tendency to co-express both a proximal airway secretory program as well as an alveolar type 2 cell program, which can be minimized by inhibiting endogenous Wnt signaling. Our results provide global profiles of engineered lung cell fates, a guide for improving their directed differentiation, and a human model of the developing airway

Variability of extracorporeal cardiopulmonary resuscitation utilization for refractory adult out-of-hospital cardiac arrest: an international survey study.

Objective: A growing interest in extracorporeal cardiopulmonary resuscitation (ECPR) as a rescue strategy for refractory adult out-of-hospital cardiac arrest (OHCA) currently exists. This study aims to determine current standards of care and practice variation for ECPR patients in the USA and Korea. Methods: In December 2015, we surveyed centers from the Korean Hypothermia Network (KORHN) Investigators and the US National Post-Arrest Research Consortium (NPARC) on current targeted temperature management and ECPR practices. This project analyzes the subsection of questions addressing ECPR practices. We summarized survey. Results: Overall, 9 KORHN and 4 NPARC centers reported having ECPR programs and had complete survey data available. Two KORHN centers utilized extracorporeal membrane oxygenation only for postarrest circulatory support in patients with refractory shock and were excluded from further analysis. Centers with available ECPR generally saw a high volume of OHCA patients (10/11 centers care for \u3e75 OHCA a year). Location of, and providers trained for cannulation varied across centers. All centers in both countries (KORHN 7/7, NPARC 4/4) treated comatose ECPR patients with targeted temperature management. All NPARC centers and four of seven KORHN centers reported having a standardized hospital protocol for ECPR. Upper age cutoff for eligibility ranged from 60 to 75 years. No absolute contraindications were unanimous among centers. Conclusion: A wide variability in practice patterns exist between centers performing ECPR for refractory OHCA in the US and Korea. Standardized protocols and shared research databases might inform best practices, improve outcomes, and provide a foundation for prospective studies