Multispectral refractive tomography (MRT) may be a useful tool for assessing relative peripheral refraction (RPR), according to a study published in Photodiagnosis and Photodynamic Therapy. 

Researchers conducted an analysis to determine a relationship between RPR and retinal microvasculature in young adults. They included 278 eyes of 139 participants in the study (mean age 26.51±3.82 years, 100 women, 131 with myopia) and performed ophthalmic exams, MRT, optical coherence tomography-angiography (OCT-A) imaging, and obtained intraocular pressure (IOP) and axial length measurements. An Analysis of variance (ANOVA) test determined refraction difference values (RDVs) in different rings of the eye. 

Investigators noted the 30°-45°/45°-53° RDV was significantly greater than the inner rings in both eyes (0.63±0.64, 0.71±0.61, P =.035 and 1.09±0.93, 1.28±0.95, P <.001 for the OD and OS, respectively), and they witnessed an increase in RPR from the inner to outer rings. Furthermore, RDV in the superior sector (0.19±0.91, 0.34±0.88, P =.003, OD and OS, respectively) was most significantly reduced among all sectors, while RDV in the nasal sector (1.00±0.82, 0.92±0.82, P =.11, OD and OS, respectively) was significantly greater than that in the temporal sector (0.44±0.81, 0.71±0.77, P <.001, OD and OS, respectively). They also observed RDV was negatively associated with both radial peripapillary capillary plexus density and macular thickness using stepwise multiple linear regression analysis. 


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Investigators highlight the shortcomings of the current methods of RPR assessment: “Major objective optometry, including retinoscopy, photoretinoscopy, autorefraction and aberrometry, is usually adopted under various specific head and eye positions. In addition, the low accuracy of retinal location and a limited VOF [view of field] (less than 40°) may restrict the clinical application to a degree.”

However, they paint a hopeful picture using novel MRT technology: “MRT can quantitatively measure RPR in a wide VOF (53°) as well as in specific retinal sectors with a single shot and without various specific eye positions. The results are automatically output and intelligible.”

Study limitations include a failure to assess peripheral axial length and OCT-A images.  

Reference

Li Z, Yang Z, Liao Y, et al. Relative peripheral refraction characteristics and their relationship with retinal microvasculature in young adults: using a novel quantitative approach. Photodiagnosis Photodyn Ther. Published online February 5, 2022. doi:10.1016/j.pdpdt.2022.102750