| Abstract |
The onset of presbyopia at the age of 40 and the continual decline in the amplitude
of accommodation until the age of 55 has always led mid-age people to face several
problems regarding tasks that acquire working at near distances. Although treating
presbyopia has always been an epicenter of clinical studies with numerous
approaches, new actions in the scientific community aim to make the “old” eye young
again. Therefore, barring traditional approaches in correcting presbyopia, such as
spectacles, contact lenses and surgical techniques, a new viewpoint has gained
interest which indicates the use of a commercially ophthalmic miotic drug in order to
increase Depth-of-Focus (DOF) by decreasing the pupil size. As pupil size is
responsible for the amount of light entering the eye, it is also highly relevant to the
potential success of many methods for improving the vision of presbyopes.
The work conducted in this thesis is a pilot study, in which a drop of 1% pilocarpine
(miotic drug) was used in the non-dominant eye of 10 presbyopic subjects who
underwent a range of measurements to assess any advantages in visual
performance monocularly, and binocularly. Near and distance Visual Acuity (using
logMAR charts), defocus curves (using a Landolt C optotype) and reading
performance (reading acuity and reading speed) were evaluated, before and after
instillation of pilocarpine, to determine if there were any benefitable changes
throughout this process. Furthermore, Near Activity Visual Questionnaire (NAVQ)
was used to subjectively asses participants’ satisfaction concerning near activity
during the study.
Reducing pupil diameter, using 1% pilocarpine in the non-dominant eye, showed a
minor, non-statistically significant, improvement in near acuity, while keeping good
distance visual acuity. Defocus curves showed some enhancement of DOF, by
improving acuity for specific near vergences. Furthermore, a significant improvement
in some reading performance metrics was found after pilocarpine instillation,
especially for binocular reading speed. Taking into account the outcome of this work, there are positive signs that the
current approach may be of importance for future applications and further research
in the correction of presbyopia, specifically in early presbyopes.
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An investigation in change of depth of focus with constriction of the pupil
