Related Experiment Video
Updated: Jan 22, 2026

Simulating the Mechanics of Lens Accommodation via a Manual Lens Stretcher
Published on: February 23, 2018
Accommodation changes after visian implantable collamer lens with central hole for high myopia: A STROBE-compliant
Minjie Chen1, Qiurong Long2, Hao Gu2
1Department of Ophthalmology, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou.
Abstract:
To characterize the accommodative changes in high-myopic patients after the implantation of the Visian implantable collamer lens with a central hole (ICL V4c).This prospective study enrolled 30 patients (60 eyes) with uneventful surgery of ICL V4c implantation. Parameters including amplitude of accommodation (AA), monocular and binocular facility of accommodation (FA), positive relative accommodation (PRA), negative relative accommodation (NRA), near point convergence (NPC), accommodative response, and accommodation convergence/accommodation (AC/A) ratio were assessed before surgery, at 1 and 3 months postoperatively.Mean preoperative SE was -10.86 ± 3.87 diopter (D) (range, -6.5D to -22D), which improved to 0.27 ± 0.51D at 1 month and 0.09 ± 0.47D at 3 months after surgery (P <.001). Significant improvements in AA, NRA, PRA, NPC, monocular, and binocular FA were seen at 1 month and 3 months postoperatively compared to the values before surgery (P <.05), but the difference between 1 month and 3 months were not obvious (P >.05) except for binocular FA (P = .002). However, no significant changes were seen in either AC/A ratio or accommodative response at any postoperative follow-ups in contrast to those before surgery (P >.05). Similar changes in accommodative function were found in patients with less myopia (> -10.00D) and those with more myopia (≤10.00D) (P >.05).The accommodative function of eyes after the implantation of ICL V4c is enhanced and stabilizes at 1 month, except for the AC/A ratio and accommodative response. The clearer vision and increased amount of accommodation for near target account for the majority of the improvement.
Related Concept Videos
The Central Dogma
The Central Dogma
RNA is the Missing Link Between DNA and Proteins
In the early 1900s, scientists discovered that DNA stores all the information needed for cellular functions and that proteins perform most of these functions. However, the mechanisms of converting genetic information into functional proteins remained unknown for many years. Initially, it was believed that a single gene is...
Detection of Black Holes
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Measures of Central Tendency
Trait Centrality
What is Central Tendency?
The central tendency is the most conventionally used data characteristic. It is a...

