Development of a new algorithm based on FDT Matrix perimetry and SD-OCT to improve early glaucoma detection in primary care

Serafini R, Lakhtakia S, Valliani AA, Warburton AJ, Patel A, Zhou D, Sklar B, Chelnis J, Elahi E. Portable hardware & software technologies for addressing ophthalmic health disparities: A systematic review

Vision impairment continues to be a major global problem, as the WHO estimates 2.2 billion people struggling with vision loss or blindness. One billion of these cases, however, can be prevented by expanding diagnostic capabilities. Direct global healthcare costs associated with these conditions totaled $255 billion in 2010, with a rapid upward projection to $294 billion in 2020. Accordingly, WHO proposed 2030 targets to enhance integration and patient-centered vision care by expanding refractive error and cataract worldwide coverage. Due to the limitations in cost and portability of adapted vision screening models, there is a clear need for new, more accessible vision testing tools in vision care. This comparative, systematic review highlights the need for new ophthalmic equipment and approaches while looking at existing and emerging technologies that could expand the capacity for disease identification and access to diagnostic tools. Specifically, the review focuses on portable hardware- and software-centered strategies that can be deployed in remote locations for detection of ophthalmic conditions and refractive error. Advancements in portable hardware, automated software screening tools, and big data-centric analytics, including machine learning, may provide an avenue for improving ophthalmic healthcare.

Non-standard computer perimetry in the diagnosis of some optic neuropathies

Modern computer perimetry is divided into traditional white stimulus-on-white background, the gold standard of which is perimetry performed by using expert class perimeters Humphrey and Octopus and therefore called standard automatic or automated perimetry (SAP), and non-traditional or non-standard perimetry, which differs, first of all, in a different nature of a stimulus. The article is a review devoted to the assessment of the diagnostic capabilities of non-standard computer perimetry in the form of different variants of perimetry with doubling the spatial frequency (Frequency Doubling Technology Perimetry or FDT perimetry), which is performed by using perimeters of the 1st (Carl Zeiss Humphrey 710 Visual Field / FDT, 1997) and the 2nd (Carl Zeiss Humphrey Matrix / HM 715, 800 Visual Field Analyzer, 2005, 2010) generation. Most authors consider that FDT perimetry is effective in a glaucoma screening and, possibly, in monitoring a glaucomatous process, but only a few authors consider that non-standard perimetry method can be useful in diagnosing optic neuropathies of a different nature.

Does Retinal Ganglion Cell Loss Precede Visual Field Loss in Glaucoma?

It is often said that substantial retinal ganglion cells are lost before glaucomatous damage is detected by standard automated perimetry. There are 4 key articles referenced to support this belief. To test the hypothesis that the 4 key articles are incorrectly cited, the publications in the first 6 months of 2019 that reference 1 or more of these 4 articles were examined. In particular, the degree to which the quotes from these 2019 publications accurately reflected the evidence in the 4 key articles was assessed. These quotes are inadequately supported by the data, and in some cases even by the conclusions found in the abstracts of the key articles. This is despite several review articles that have questioned the evidence in these key articles. Further, a case can be made that the evidence in the key articles better supports the opposite conclusion. That is, the data suggest that sensitivity loss can be seen on standard automated perimetry before retinal ganglion cells are missing.