Effects of Two Commonly Used Mydriatics on Choroidal Thickness: Direct and Crossover Effects

Abstract

The findings of the present study revealed that tropicamide and phenylephrine cause a decrease in choroidal thickness.

Choroidal vascularity index changes after vitreomacular surgery

“…The OCT examination was carried out immediately after the visual acuity (VA) measurement and before dilation, as per protocol, to avoid vascular choroidal effects due to the dilating drops (Kara et al 2014). A 1050-nm wavelength light source (swept-source) optical coherence tomography device (Topcon DRI OCT; Triton) was used, scanning at 100.000 A scans/second, and providing a very clear and defined visualization of the choroid layer.…”

“…A 1050-nm wavelength light source (swept-source) optical coherence tomography device (Topcon DRI OCT; Triton) was used, scanning at 100.000 A scans/second, and providing a very clear and defined visualization of the choroid layer. The OCT examination was carried out immediately after the visual acuity (VA) measurement and before dilation, as per protocol, to avoid vascular choroidal effects due to the dilating drops (Kara et al 2014). A single experienced technician, who was blinded to the identity of the subjects and was not involved in the data analysis, acquired all the images.…”

The Influence of the Autonomic Nervous System on the Human Choroid

“…results. Some authors demonstrated a decrease in choroidal thickness in both the treated and fellow eyes after topical phenylephrine administration (Kara et al, 2014), whereas others have reported no change in choroidal thickness (Bajenova et al, 2012) ( Table 1.7.6.1). Similarly, reports of changes in choroidal blood flow as a result of stimulation of the sympathetic system are also equivocal with both reductions in ocular blood flow (Lanigan et al, 1988;Takayama et al, 2009) and no change in posterior eye circulation in healthy human subjects being reported (Takayama et al, 2004;Robinson et al, 1985;Schmetterer et al, 1996).…”

“…Some studies have found that application of the non-selective muscarinic antagonist 1% tropicamide does not have any influence on choroidal thickness (Mwanza et al, 2013;Öner et al, 2016), while other authors have observed a decrease in choroidal thickness after administration of 1% tropicamide or 1% cyclopentolate (Kara et al, 2014;Yuvaci et al, 2015). Contrary to these findings, three recent studies have reported that 2% homatropine, 1% atropine and 1% cyclopentolate significantly increased subfoveal choroidal thickness Öner et al, 2016;Zhang et al, 2016 selective antagonist pirenzepine (Shih et al, 1999, Siatkowski et al, 2004Chua et al, 2006;Chia et al, 2012, Chia et al, 2016.…”

“…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.…”