The effect of topical anti-muscarinic agents on subfoveal choroidal thickness in healthy adults

Abstract

Purpose To investigate the effects of tropicamide and cyclopentolate, which are two anti-muscarinic agents commonly used in the ophthalmologic practice, on subfoveal choroidal choroidal thickness (ChT) in healthy adults. Methods A total of 74 healthy adult subjects were enrolled in the study. Subjects were randomly divided into two groups: (1) cyclopentolate group (n = 37) in which the right eye (study eye) of each subject received topical cyclopentolate 1%, and the fellow eye (control eye) received artificial tears and (2) tropicamide group (n = 37) in which the right eye (study eye) of each subject received topical tropicamide 1% and the fellow eye (control eye) received artificial tears. Each topical medication was applied three times with 10-min intervals. ChT measurements were performed at baseline and 40 min after the last drops of the topical medications by enhanced depth imaging (EDI) optical coherence tomography (OCT). Results In the cyclopentolate group, subfoveal ChT significantly increased in the study eyes (P = 0.013), whereas it did not significantly change in the control eyes (P = 0.417). On the other hand, in the tropicamide group, no significant subfoveal ChT changes were observed in either the study eyes (P = 0.715) or the control eyes (P = 0.344). Conclusions The current study demonstrated that cyclopentolate caused significant choroidal thickening, whereas tropicamide had no significant effect on ChT in healthy adults. As a result, mydriasis by cyclopentolate may complicate ChT measurements by EDI OCT. Use of tropicamide may provide more reliable results for evaluation of ChT in ocular pathologies.

Choroidal Thickness and Ametropia in Children: A Longitudinal Study

“…Some studies showed that cycloplegia could modify ChT. One of them found a decrease of ChT with cyclopentolate (29); another demonstrated an increase (30). With the decision to study children from 2 years of age, we used only OCT imaging of the horizontal section through the fovea as it was not possible for these young patients to maintain fixation for longer than a few seconds.…”

Change in the Ophthalmobiometric Parameters in Myopia and Hyperopia under the Influence of Cycloplegia

“…С другой стороны, авторы аналогичных ис-следований, проведенных с использованием такого же оборудования (enhanced depth imaging optical coherence tomography, EDIOCT), рассматривали изменение хори-оидеи после закапывания мидриатиков как результат непосредственного действия на нее фармацевтических агентов, в частности антимускаринового вещества ци-клопентолата. При этом в одной из работ установлено достоверное утолщение хориоидеи под действием ци-клопентолата в отличие от других мидриатиков (Тропи-камида), не оказавших на нее достоверного воздействия [26]. Авторы другой работы, наоборот, обнаружили достоверное уменьшение толщины хориоидеи под дей-ствием всех мидриатиков, включая Циклопентолат, и делают особый акцент на отсутствие корреляции этих изменений с характерными для мидриаза изменениями параметров передней камеры -увеличением ее глуби-ны, объема и уплощением хрусталика [28].…”

The Influence of the Autonomic Nervous System on the Human Choroid

“…An increase in choroidal thickness following administration of anticholinergic drugs (Arumugam andMcBrien, 2012, Nickla et al, 2013a) or surgical modification of parasympathetic input to the eye Wildsoet, 1996, Nickla andSchrodel, 2012) have been demonstrated in a number of different species. However, there is limited evidence regarding choroidal thickness changes after administration of anticholinergic agents in human subjects (Mwanza et al, 2013;Kara et al, 2014;Yuvaci et al, 2015;Öner et al, 2016;Zhang et al, 2016). Human clinical studies also indirectly support the notion that cholinergic transmission can influence choroidal thickness and refractive error development.…”

“…Choroidal thickness changes during the development and progression of myopia may be regulated by the autonomic nervous system (Troilo et al, 2000;, Öner et al, 2016, and may be passively or actively involved in the control, of eye growth.…”

“…Imposed defocus produces rapid changes in the choroid; this was first documented in the chick model and subsequently confirmed in mammals including humans. The magnitude of choroidal thickness variations found in humans and mammals is much smaller than in avian species (10-20 µm vs. ≈100 µm respectively), Wildsoet and Wallman, 1995;Hung et al, 2000;McBrien et al, 2000;Hewlett and McFadden, 2009;Nickla and Wallman, 2010a;Read et al, 2010b, Chakraborty et al, 2012Chiang et al, 2015;Öner et al, 2016;Zhang et al, 2016). Choroidal thickness changes observed during emmetropization represent a physiological response to external stimulation (optical defocus), which aims to adjust the retinal position to provide clear vision and drive growth of the eye.…”