Recently, Ruiz-Medrano et al.
1 did a study to determine choroidal thickness (CT) profile in a healthy population using swept-source optical coherence tomography (SS-OCT). In their study, the patient profiles (age, sex, and spherical equivalent) were collected to identify potential factors associated with CT. However, axial length is another important factor influencing CT, which should be considered in their study. Several studies investigating factors associated with CT have demonstrated the significant relationship between CT and axial length.
2–4 Specially, in the previous study that included 3468 individuals, Wei et al.
2 found that the eyes with longer axial length have a thinner choroid. Thus, if Ruiz-Medrano et al.
1 consider axial length in their study, their study thereby will be strengthened.