Researchers have demonstrated that quantifying axon thickness in the retinal nerve fiber layer (RNFL) can be reproducibly measured by trained technicians in a multiple sclerosis center using optical coherence tomography (OCT), according to a study published in the September issue of Archives of Neurology.
OCT is a promising new imaging method that has been used predominantly by opthalmologists to monitor glaucoma. It is being considered as a potential outcome measure in multiple sclerosis (MS) clinical trials, but no data exist on the reproducibility of this technique in MS centers, according to background information in the study.
Researchers sought to determine the reproducibility of OCT measurement of mean RNFL thickness in the undilated eyes of healthy control subjects and patients with MS.
“We found excellent agreement with respect to interrater (intraclass correlation [ICC], 0.89), intrarater (ICC, 0.98) and intervisit (ICC, 0.91) results. Mean RNFL thickness did not vary significantly among research centers for patients with MS (93, 92, and 90 µm) or among healthy controls (103, 105 and 104 µm) by site,” the authors wrote.
The findings demonstrated that mean RNFL thickness can be reproducibly measured by trained technicians in an MS center using the OCT-3 model, the authors concluded.