The direction of pull of the muscles forms a 23Â° angle relative to the visual axis in the primary position, giving rise to secondary and tertiary functions. The secondary action of vertical rectus muscles is torsion. The superior rectus is an incyclotorter, and the inferior rectus is an excyclotorter.
-Marcia. Dear Marcia, Eyelash growth serums generally contain either a prostaglandin derivative, like prescription Latisse, or over-the-counter Revitalash; peptides, like Jan Marini Growth Serum; or vitamins, like Peter Thomas Roth Lashes to Die For.
It is also possible for a difference in eyelash length, thickness, fullness, pigmentation, number of eyelash hairs, and/or direction of eyelash growth to occur between eyes. These differences, should they occur, will usually go away if you stop using the serum.