scholarly journals Evaluation of Disk Halo Size after Implantation of a Collamer Lens with a Central Hole (ICL V4c)

2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Xun Chen ◽  
Tian Han ◽  
Feng Zhao ◽  
Huamao Miao ◽  
Xiaoying Wang ◽  
...  

Purpose. To investigate disk halo size changes produced by a glare source after surgical insertion of an implantable collamer lens with a central hole (ICL V4c) for myopia correction. Methods. In this prospective study, disk halo size and pupillary light response with a vision monitor were measured preoperatively and at 1 week, 1 month, and 3 months postoperatively. Pupillary light response parameters included contraction amplitude, latency, duration, and velocity; dilation latency, duration, and velocity; and initial, maximum, minimum, and average pupil diameters. Results. Forty-two right eyes of 42 patients were enrolled. Postoperative uncorrected distance visual acuity was better than or equal to 20/20 in all eyes. Compared to preoperative values, disk halo size showed no significant difference at 1 week postoperatively (P>0.05) and then decreased significantly at 1 and 3 months postoperatively (both P<0.001). Contraction amplitude and velocity, as well as dilation velocity, decreased significantly at all postoperative time points (all P<0.001). Disk halo size at 3 months postoperatively was significantly correlated with initial (r = 0.446, P=0.003), maximum (r = 0.483, P=0.001), minimum (r = 0.425, P=0.005), and average pupil diameters (r = 0.474, P=0.002). Conclusions. After ICL V4c implantation, disk halo size was reduced in the short term. Patients with smaller pupil sizes during pupillary response to light experienced smaller halos after ICL V4c implantation.

Author(s):  
Abhishek Chaturbedi ◽  
Jitendra Thakur ◽  
Aashik Jha ◽  
Milan Niraula

Objective of the Study: This paper has been aimed to determine whether the pharmacological neuromuscular blockade with rocuronium during emergency Rapid Sequence Intubation (RSI) affected pupillary response to light (PLR) in patients with brain insult as compared to patients who had non- neurological illness. Previous studies elucidated that RSI with pharmacological neuromuscular blockade does not affect PLR, except in patients with significant neurological lesion. Our objective is to examine the validity of existing but scarce literature on this subject, with further stratification of patients involved in this study into neurological and non-neurological disease groups. Methods: This was a prospective case-reference study of case group with brain insult patients compared with reference group of patients without neurological diseases undergoing RSI in emergency settings. It is single centered study, conducted from October 2019 till May 2020. A pair of a neurosurgeon and a medical officer assessed pupillary light response after administration of neuromuscular blockade and intubation, each blinded to other’s assessment of PLR. Cases without pupillary response before RSI intubation were excluded. The primary outcome measure was clinically observable Pupillary Light Response (PLR) following neuromuscular blockade with Rocuronium in each group. Results: We examined 50 patients undergoing RSI with Rocuronium, either in emergency department or Intensive Care Unit (ICU), 25 each in index and reference group respectively. All patients in the reference group showed PLR after RSI. Of case group patients receiving RSI, only15 of 25 (60%) demonstrated PLR after RSI. This was statistically significant (p value<0.05) when compared to number of patients with intact PLR after RSI in reference group. Cohen’s Kappa Coefficient (k) for inter-observer agreement was 0.70. Conclusion: Rocuronium does not appear to affect PLR after emergent RSI in patients without brain injury. Only in patients with known brain insult showed impaired PLR, suggesting impaired pupillary light reflex mechanism may be the culprit for this aberration, rather than pharmacological neuromuscular blockade.


2019 ◽  
Author(s):  
Tianrui He ◽  
Yi Zhu ◽  
Jibo Zhou

Abstract Background The current study compared optical quality before and after implantation of a posterior chamber phakic intraocular lens with a central hole [V4c implantable collamer lens (ICL)] under bright and dark lighting conditions by means of the Optical Quality Analysis System™ (OQAS; Visiometrics, Terrassa, Spain). Methods This prospective study involved 91 eyes of 46 consecutive patients undergoing implantation of a V4c ICL (15 males and 31 females). The modulation transfer function (MTF) cutoff frequency, Strehl ratio, objective scattering index (OSI), and predicted visual acuities (PVAs; 100%, 20%, and 9%), under different lighting conditions, were measured before and 1 week, 1 month, and 3 months after surgery. Results All optical parameters showed significant improvements, at all time points, under dark condition after surgery. We observed no significant changes in PVA 9% at 1 week (P=0.12) or 1 month after surgery (P=0.08) under light condition; but all other postoperative parameters improved significantly. Comparing the two lighting conditions, the OSI decreased more under dark conditions at 1 week (P=0.02), 1 month (P=0.004), and 3 months (P=0.002), but there was no significant difference in any other parameter. In addition, patients were divided into a high myopia group (group H) and a super-high myopia group (group S), the group S improved significantly more than group H in all parameters, under both bright and dark conditions. Conclusions V4c ICL implantation improved optical quality under both bright and dark lighting conditions, and had a better ability to reduce the extent of scattering in the dark. Furthermore, group S achieved greater improvement in visual quality, which should be considered by physicians before surgery.


2020 ◽  
pp. 112067212096903
Author(s):  
Huseyin Bugra Turk ◽  
Gulfidan Bitirgen ◽  
Gunhal Satirtav ◽  
Hurkan Kerimoglu

Purpose: This study aims to evaluate the pupillary light reflex measured with dynamic pupillometry in patients who underwent retinal laser photocoagulation due to unilateral retinal vein occlusion (RVO). Methods: A total of 48 patients with unilateral RVO were included in the study. Thirty-four patients had undergone retinal laser photocoagulation while the remaining 14 patients that did not undergo laser treatment were observed for control purposes. Of the laser-treated eyes, 14 eyes (41.2%) had central RVO (CRVO) and 20 eyes (58.8%) had branch RVO (BRVO). Among the 14 patients with RVO without laser treatment, nine eyes (64.3%) had CRVO and five eyes (35.7%) had BRVO. Pupillary light reflexes were assessed with dynamic pupillometry (MonPackOne®; Metrovision, France). The parameters of the eyes with RVO were compared with that of fellow healthy eyes. Results: Mean patient age was 65.8 ± 10.4 years and median time after photocoagulation was 25.5 months. Eyes that received laser photocoagulation had lower pupil contraction amplitude ( p = 0.037), prolonged contraction latency ( p = 0.027), slower contraction velocity ( p = 0.043), and slower dilation velocity ( p < 0.001) compared to healthy fellow eyes. Subgroup analysis revealed that eyes with CRVO had lower contraction amplitude ( p = 0.013) and slower dilation velocity ( p = 0.003), and eyes with BRVO had slower dilation velocity ( p = 0.003). Non-laser-treated eyes with RVO revealed no significant difference in any of the pupillary light reflex parameters compared to fellow eyes. Conclusion: Laser-treated eyes with RVO demonstrated changes in pupillary light reflex parameters including reduced contraction amplitude, prolonged contraction latency, and slower contraction and dilation velocities measured with dynamic pupillometry.


2019 ◽  
Vol 257 (12) ◽  
pp. 2789-2793 ◽  
Author(s):  
Tian Han ◽  
Feng Zhao ◽  
Xun Chen ◽  
Huamao Miao ◽  
Zhuoyi Chen ◽  
...  

Abstract Purpose To investigate changes in objective disk halo size produced by a glare source after small incision lenticule extraction (SMILE) for myopia correction. Methods This prospective clinical study included 45 right eyes of 45 patients with a mean age of 25.40 ± 5.06 years and mean spherical equivalent (SE) of − 6.08 ± 1.90 diopters. Disk halo size was measured with a vision monitor before surgery and at postoperative 1 week and 3 months. Other information was collected, including age, SE, lenticule thickness, lenticule diameter, dark pupil, and pupillary response to light parameters (initial diameter; amplitude, latency, duration, and velocity of contraction; latency, duration, and velocity of dilation; and maximum, minimum, and average pupil size). Results Compared to preoperative values, disk halo size increased significantly at postoperative 1 week (P = 0.026) and returned to baseline at postoperative 3 months (P = 0.349). Preoperative disk halo size significantly correlated with SE (r = − 0.346, P = 0.020), minimum pupil size (r = 0.365, P = 0.014), and average pupil size (r = 0.310, P = 0.038). Disk halo size at postoperative 1 week was significantly correlated with age (r = 0.324, P = 0.030) and minimum pupil size (r = 0.297, P = 0.047). Disk halo size at postoperative 3 months was significantly correlated with lenticule diameter (r = − 0.362, P = 0.015), initial diameter (r = 0.311, P = 0.037), maximum pupil size (r = 0.312, P = 0.037), minimum pupil size (r = 0.440, P = 0.002), and average pupil size (r = 0.373, P = 0.012). Conclusions After SMILE, disk halo size demonstrated a temporary increase and then returned to baseline.


1995 ◽  
Vol 12 (2) ◽  
pp. 281-284 ◽  
Author(s):  
J.K. Oh ◽  
D.L. Bohnsack ◽  
J.B. Troy ◽  
Ch. Enroth-Cugell

AbstractPupillary area was measured in urethane-anesthetized cats as a function of retinal illuminance. When appropriate corrections are made for differences in experimental procedures, it was found that the pupillary response of the urethane-anesthetized cat's eyes to light was basically unchanged from that of the alert behaving cat. This preparation may therefore be a very satisfactory one in which to study the pupillary response pathway in a higher mammal.


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