Photo Credit: miodrag ignjatovic
The following is a summary of “Number of macula optical coherence tomography scans needed to detect glaucoma progression,” published in the December 2024 issue of Ophthalmology by Mahmoudinezhad et al.
Researchers conducted a retrospective study to assess the impact of testing frequency on the time required to detect statistically significant glaucoma progression for ganglion cell complex (GCC) using optical coherence tomography (OCT).
They enrolled 332 eyes from 201 patients with glaucoma across multicenter glaucoma registries, with an average follow-up of 4.4 years. Patients who had 4 or more OCT tests were selected to calculate longitudinal rates of GCC thickness change over time using linear regression. A computer simulation was employed to generate real-world GCC data and assess the time required to detect progression at various loss rates and testing frequencies based on variability estimates. The time and accuracy to detect worsening of progression were then calculated.
The results showed that as testing frequency increased, the time required to detect a statistically significant negative GCC slope decreased, although not in a proportional manner. Eyes with a GCC loss of −1 µm/year progressed after 3.8, 2.6, and 2.2 years on average, with testing conducted once, twice, and 3 times per year, respectively. For eyes with a GCC loss of −1.5 µm/year, progression was detected after 3.3, 2.2, and 1.8 years on average, respectively.
Investigators concluded the increasing macular OCT testing frequency to 3 times per year more sensitively detects progression, but 2 times per year testing might be sufficient in clinical settings to balance progression detection with reduced healthcare burden.
Source: bjo.bmj.com/content/early/2024/12/11/bjo-2023-324916
