Comparison of two different optical coherence tomography angiography devices in detecting healthy versus glaucomatous eyes - an observational cross-sectional study.

BACKGROUND: To understand the differences between two different optical coherence tomography angiography (OCTA) devices in detecting glaucomatous from healthy eyes by comparing their vascular parameters, diagnostic accuracy and test-retest reliability. METHODS: A cross-sectional observational study was performed on healthy and glaucoma subjects, on whom two sets of OCTA images of optic disc and macula were acquired using both AngioVue (Optovue, USA) and Swept Source (Topcon, Japan) OCTA devices during one visit. A novel in-house software was used to calculate the vessel densities. Diagnostic accuracy of the machines in differentiating healthy versus glaucomatous eyes was determined using area under the receiver operating characteristic curve (AUROC) and test-retest repeatability of the machines was also evaluated. RESULTS: A total of 80 healthy and 38 glaucomatous eyes were evaluated. Glaucomatous eyes had reduced mean vessel density compared to healthy controls in all segmented layers of the optic disc and macula using AngioVue (p ≤ 0.001). However, glaucomatous eyes had higher mean vessel density on optic disc scans using Swept Source, with lack of statistically significant difference between healthy and glaucomatous eyes. The AUROC showed better diagnostic accuracy of AngioVue (0.761-1.000) compared to Swept Source (0.113-0.644). The test-retest reliability indices were generally better using AngioVue than Swept Source. CONCLUSIONS: AngioVue showed better diagnostic capability and test-retest reliability compared to Swept Source. Further studies need to be undertaken to evaluate if there is any significant difference between the various machines in diagnosing and monitoring glaucoma.

An unexpected cause for aplastic anaemia in an elderly woman.

Aplastic anaemia is a rare clinical syndrome associated with diminished or absent precursors in the bone marrow. Acquired aplastic anaemia secondary to human immunodeficiency virus (HIV) is very rare. We present a 71-year-old woman with severe aplastic anaemia secondary to HIV infection, which was after extensive exclusion of other causes. She achieved undetectable viral load after 5 months of combination antiretroviral therapy but remains profoundly pancytopenic, complicated by recurrent infectious and bleeding complications. HIV infection should be considered in patients with pancytopenia.