Duration of contact lens removal before myopic refractive surgery

2020 ◽  
pp. 112067212094910
Author(s):  
Raneen Shehadeh-Mashor ◽  
Michael Mimouni ◽  
Yinon Shapira ◽  
Tzahi Sela ◽  
Gur Munzer ◽  
...  

Purpose: To compare refractive surgery outcomes in patients with different periods without contact lenses prior laser surgery. Materials and methods: Patients included in this study underwent myopic keratorefractive laser surgery between January 2005 and December 2014. Patients were divided into three groups based on the duration of time passed free of soft contact lens wearing prior to final preoperative evaluation and surgery (<24 h, 1–3 days or >3 days). Spectacle wearers served as a control group. Postoperative safety index, efficacy index and % of eyes within 0.5 D of the four groups were compared. A general linear model was used to compare main outcomes while adjusting for age, gender, preoperative measurements, and procedure type (LASIK vs PRK). Results: Overall, 19,747 eyes were included. Soft contact lenses were worn by 42.3% (<24 h: 4.8%, 1–3 days: 18.5% and >3 days: 19.0%) and spectacles by 57.7% prior to surgery. In the PRK group, after adjusting for differences in baseline variables, the <24-h group had a significantly lower efficacy index than all the other groups. There were no significant differences between groups in terms of % eyes within ±0.5 D of intended correction ( p = 0.55) or safety index (0.20). In the LASIK group, after adjusting for differences in baseline variables, there were no significant differences between groups in all primary outcomes. Conclusion: Soft contact lenses should be removed at least 24 h prior to final preoperative evaluation and refractive surgery, especially for patients undergoing PRK.

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Xiaohong Hu ◽  
Lingyun Hao ◽  
Huaiqing Wang ◽  
Xiaoli Yang ◽  
Guojun Zhang ◽  
...  

Soft contact lenses can improve the bioavailability and prolong the residence time of drugs and, therefore, are ideal drug carriers for ophthalmic drug delivery. Hydrogels are the leading materials of soft contact lenses because of their biocompatibility and transparent characteristic. In order to increase the amount of load drug and to control their release at the expected intervals, many strategies are developed to modify the conventional contact lens as well as the novel hydrogel contact lenses that include (i) polymeric hydrogels with controlled hydrophilic/hydrophobic copolymer ratio; (ii) hydrogels for inclusion of drugs in a colloidal structure dispersed in the contact lenses; (iii) ligand-containing hydrogels; (iv) molecularly imprinted polymeric hydrogels; (v) hydrogel with the surface containing multilayer structure for drugs loading and releasing. The advantages and disadvantages of these strategies in modifying or designing hydrogel contact lenses for extended ophthalmic drug delivery are analyzed in this paper.


1998 ◽  
Vol 14 (6) ◽  
pp. 631-635
Author(s):  
Efstathios T Detorakis ◽  
Dimitrios S Siganos ◽  
Vasilios M Houlakis ◽  
Vasilios P Kozobolis ◽  
Ioannis G Pallikaris

The Eye ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 59-63
Author(s):  
S. V. Zimovets ◽  
A. Ya. Sverdlik

The article describes the effect of decorative cosmetics on the material of soft contact lenses and studies specific features that can be observed in SCL wearers who use cosmetics extensively. Examples of complications associated with the use of various cosmetic products that may occur in contact lens wearers are given. Conclusion: in cases when patients have complaints about discomfort and dry eyes, doctors should pay attention to the amount of decorative cosmetics used as well as study the effect it can have on the surface of the contact lenses.


F1000Research ◽  
2016 ◽  
Vol 5 ◽  
pp. 2803
Author(s):  
Kareem Allinjawi ◽  
Sharanjeet-Kaur Sharanjeet-Kaur ◽  
Saadah Mohamed Akhir ◽  
Haliza Abdul Mutalib

Aim: The purpose of this study was to determine the changes in the relative peripheral refractive error produced by soft single vision contact lenses in myopic schoolchildren. Methods: 27 myopic schoolchildren aged between 13 to 15 years were included in this study. The measurements of central and peripheral refraction were made only on the right eye using a Grand-Seiko WR-5100K open-field autorefractometer without contact lens (WL), and with wearing single vision contact lens (SVCL). Refractive power was measured at center and horizontal eccentricity between 35° temporal to 35° nasal visual field (in 5° steps). Results: SVCL showed an increase in peripheral hyperopic defocus at the nasal and temporal visual field compare with baseline, but this change was not statistically significant (p=0.129). Conclusion: Wearing single vision soft contact lenses increases the relative peripheral hyperopic defocus in myopic schoolchildren.


2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Aleksandra Debeljković Mitrović ◽  
Dragomir Stamenković ◽  
Manuel Conte ◽  
Božica Bojović ◽  
Spomenko Mihajlović

In this paper results of comparative study of the optical power of soft contact lenses (SCL) made of standard material for SCL and nanophotonic materials with different measurement techniques used for the final contact lens controllers are presented. Three types of nanophotonic soft contact lenses were made of standard polymacon material (Soleko SP38TM) incorporated with fullerene C60, fullerol C60(OH)24 and fullerene metformin hydroxylate C60(OH)12(OC4N5H10)12. For the purposes of material characterization for potential application as soft contact lenses, the optical properties of the soft contact lenses were measured by Rotlex and Nidek device. With Rotlex device the following optical results were obtained: optical power and map of defects, while with the Nidek device: optical power, cylinder power and cylinder axis. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is same to the nominal value, while this was not the case for the standard soft contact lens. Also, the quality of the nanophotonic soft contact lens is better than the standard one. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field.


2014 ◽  
Vol 679 ◽  
pp. 118-127 ◽  
Author(s):  
Deirdre M. McElroy ◽  
Luke M. Geever ◽  
Clement L. Higginbotham ◽  
Sinead M. Devery

Hydrogel soft contact lenses have been investigated as delivery systems for ophthalmic drug products in response to the need for more efficient ophthalmic drug delivery systems. Ocular drugs delivered via eye drops have a low residence time in the eye resulting in as low as 5% bioavailability of the therapeutic agent. This study investigates the effect of varying concentrations of the photoinitiator diphenyl (2,4,6-trimethylbenzoyl)-phosphine oxide (TPO) on the physicochemical properties of hydrogel soft contact lenses for ophthalmic drug delivery purposes. Contact lens samples were synthesised via photopolymerisation with a range of initiator concentration. Gel fraction and swelling results indicated that increasing the photoinitiator concentration increased the efficiency of the gel network and reduced the water content of contact lens samples. Fourier transform infra-red spectroscopy (FTIR) analysis was employed to confirm polymerisation of the lenses and also indicated the presence of residual photoinitiator in lenses with higher TPO concentrations.


2017 ◽  
Vol 2017 ◽  
pp. 1-17 ◽  
Author(s):  
L. Rico-Del-Viejo ◽  
M. Garcia-Montero ◽  
J. L. Hernández-Verdejo ◽  
S. García-Lázaro ◽  
F. J. Gómez-Sanz ◽  
...  

Objectives. To describe the past 20 years’ correction modalities for keratoconus and their visual outcomes and possible complications.Methods. A review of the published literature related to the visual outcomes and possible complications in the context of keratoconus management using nonsurgical procedures for the last 20 years (glasses and contact lenses) was performed. Original articles that reported the outcome of any correction modalities of keratoconus management were reviewed.Results. The most nonsurgical procedure used on keratoconus management is the contact lens fitting. Soft contact lenses and soft toric contact lenses, rigid gas-permeable contact lenses, piggyback contact lens system, hybrid contact lenses, and scleral and corneoscleral contact lenses form the contemporary range of available lens types for keratoconus management with contact lenses. All of them try to restore the vision, improve the quality of life, and delay surgical procedures in patients with this disease. Complications are derived from the intolerance of using contact lens, and the use of each depends on keratoconus severity.Conclusions. In the context of nonsurgical procedures, the use of contact lenses for the management of keratoconic patients represents a good alternative to restore vision and improve the quality of live in this population.


2018 ◽  
Vol 15 (2S) ◽  
pp. 65-72 ◽  
Author(s):  
M. M. Sitka ◽  
S. G. Bodrova ◽  
N. A. Pozdeyeva

Objective: to determine optimal method of progressive myopia optical correction in children and adolescents.Patients and methods. Conducted 5-year prospective clinical and instrumental examination of 494 children with myopia using orthokeratology lenses, soft contact lenses and glasses. 61 children (the average age 11.7 ± 2.36 years) with myopia –2.87 ± 1.1 D and astigmatism –0.58 ± 0.27 D used orthokeratological lens. 92 children (the average age 12.8 ± 1.51 years) with myopia –3.66 ± 1.07 D, astigmatism –0.53 ± 0.18 D wore soft contact lens. 79 children (the average age 11.52 ± 1.78 years) with myopia –1.59 ± 1.08 D, astigmatism –0.71 ± 0.54 D used glasses with monofocal lenses, with full correction. The control group consisted of 249 children (the average age 9.1 ± 1.14 years) with initial emmetropia. Determination of refraction, subjective and objective determination of accommodation, and axial length of the eye (“IOL-master”) was conducted in children.Results. The maximum progression of myopia was observed in younger children (8–9 years). Correction of myopia with orthokeratology lenses (OKLs) was accompanied by the lowest dynamics of changes in axial length (axial elongation 0,44 ± 0,32 mm) compared to the correction with soft contact lenses (SCLs) (axial elongation 0,73 ± 0,36 mm), spectacle correction (axial elongation 1,39 ± 0,47 mm) and the control group (axial elongation 0,6 ± 0,41 mm). In all children with myopia, at the beginning of the study, there were reduced values reserve of relative accommodation and an objective accommodative response. Correction of myopia with OKLs (p = 0,0002) and SCLs (p = 0,036) provides the normalization of subjective and objective reserve indication of relative accommodation in both age group in comparison of spectacles correction.Conclusion. Correction with orthokeratology lens in children with progressive myopia contributes to the minimum growth length of the eye. Correction of myopia OKLs and MKL improves of subjective and objective indicators of relative accommodation reserve. 


2013 ◽  
Vol 67 (6) ◽  
pp. 861-870 ◽  
Author(s):  
Aleksandra Debeljkovic ◽  
Lidija Matija ◽  
Djuro Koruga

This work presents comparative research of characteristics of a basic and new nanophotonic material, the latter of which was obtained by incorporation fullerene, C60, in the base material for soft contact lenses. The basic (SL38) and nanophotonic materials (SL38-A) for soft contact lenses were obtained by radical polymerization of 2-hydroxyethyl methacrylate and 2-hydroxyethyl methacrylate and fullerene, which were derived by the technology in the production lab of the company Soleko (Milan, Italy). The materials were used for production of soft contact lenses in the company Optix (Belgrade, Serbia) for the purposes of this research. Fullerene was used due to its apsorption transmission characteristics in ultraviolet, visible and near infrared spectrum. For the purposes of material characterization for potential application as soft contact lenses, network parameters were calculated and SEM analysis of the materials was performed while the optical properties of the soft contact lenses were measured by a Rotlex device. The values of the diffusion exponent, n, close to 0.5 indicated Fick's kinetics corresponding to diffusion. The investigated hydrogels could be classified as nonporous hydrogels. With Rotlex device, values of optical power and map of defects were showed. The obtained values of optical power and map of defects showed that the optical power of synthesized nanophotonic soft contact lens is identical to the nominal value while this was not the case for the basic lens. Also, the quality of the nanophotonic soft contact lens is better than the basic soft contact lens. Hence, it is possible to synthesize new nanophotonic soft contact lenses of desired optical characteristics, implying possibilities for their application in this field.


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