scholarly journals Measurement of Force Required for Anterior Displacement of Intraocular Lenses and Its Defining Parameters

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4593
Author(s):  
Mihoko Mochiji ◽  
Sachiko Kaidzu ◽  
Yoshihisa Ishiba ◽  
Yuji Matsuda ◽  
Masaki Tanito
Keyword(s):  
Pressure Gradient ◽  
Anterior Chamber ◽  
Silicone Oil ◽  
The Other ◽  
Intraocular Lenses ◽  
Vitreous Surgery ◽  
Junction Area ◽  
Anterior Displacement ◽  
Silicone Oil Tamponade ◽  
Displacement Force

Intraocular stability during or after cataract and glaucoma filtration surgeries and vitreous surgery with a gas/silicone oil tamponade might differ among intraocular lenses (IOLs). We used six different one-piece IOL models and measured the force that displaced the IOLs from the vitreous cavity to anterior chamber as a measure of stability against the pressure gradient between the anterior and posterior IOL surfaces. We measured IOL hardness, haptics junction area, and posterior IOL bulge to identify what determines the IOL displacement force. The KOWA YP2.2 IOL (1.231 mN) required significantly greater force than the HOYA XY1 (0.416 mN, p = 0.0004), HOYA 255 (0.409 mN, p = 0.0003), Alcon SN60WF (0.507 mN, p = 0.0010), and Nidek NS60YG (0.778 mN, p = 0.0186) IOLs; J&J ZCB00V IOL (1.029 mN) required greater force than the HOYA XY1 (p = 0.0032) and HOYA 255 (p = 0.0029) IOLs; the Nidek NS60YG IOL required greater force than the HOYA 255 (p = 0.0468) IOL. The haptics junction area was correlated positively with the IOL displacement force (r = 0.8536, p = 0.0306); the correlations of the other parameters were non-significant. After adjusting for any confounding effects, the haptics junction area was correlated significantly with the IOL displacement force (p = 0.0394); the IOL hardness (p = 0.0573) and posterior IOL bulge (p = 0.0938) were not. The forces that displace IOLs anteriorly differed among one-piece soft-acrylic IOLs, and the optics/haptics junction area was the major force determinant.

Hybrid 20/23-G pars plana vitrectomy in endophthalmitis and trauma: a strategic approach

2017 ◽  
Vol 28 (1) ◽  
pp. 94-97
Author(s):  
Daraius Shroff ◽  
Priyanka Gupta ◽  
Charu Gupta ◽  
Neelam Atri ◽  
Ranjan Dutta ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Retinal Detachment ◽  
Silicone Oil ◽  
Vitreous Surgery ◽  
Safety And Efficacy ◽  
Suprachoroidal Space ◽  
Strategic Approach ◽  
Pars Plana ◽  
Silicone Oil Tamponade ◽  
Difficult Cases

Purpose: To assess the safety and efficacy of hybrid vitreous surgery combining active 23-G ports with a sutured 20-G 6-mm infusion cannula for performing vitrectomy in endophthalmitis and trauma. Methods: This is a retrospective analysis of 10 eyes with endophthalmitis and 10 eyes with trauma requiring vitreous surgery, having corneal clarity suitable for vitrectomy and best-corrected visual acuity (BCVA) greater than or equal to light perception. All patients underwent hybrid 20/23-G vitrectomy. Intraoperative notes were analyzed for peroperative complications. The BCVA and retinal status at 3 months were analyzed. Results: In the endophthalmitis group, patients ranged from 5 to 85 years of age and showed varied etiologies. Retinal detachment was present in 5 eyes, which received silicone oil tamponade. Mean preoperative logMAR visual acuity (VA) was 2.29 ± 0.45, which improved to 1.10 ± 0.72 at 3 months postoperatively (p<0.001). Trauma cases ranged from 21 to 75 years of age. Retinal detachment was present in 9 out of 10 eyes, all of which received silicone oil tamponade. Preoperative logMAR VA was 2.26 ± 0.71, which improved to 1.33 ± 0.50 postoperatively (p<0.001). At 3 months postsurgery, the retina was attached in all eyes in both groups. Conclusions: The longer sutured 20-G cannula was easier to visualize through fibrin, exudates, and hemorrhage and did not slip out or enter the suprachoroidal space in any of our cases. The 23-G active ports and vitrectomy cutter enhanced safety and efficacy. Hybrid vitrectomy enabled safe surgery in these difficult cases.

Methods of correction of aphakia in silicone tamponade of the vitreous cavity

2021 ◽  
pp. 68-72
Author(s):  
G.O. Karpov ◽  
◽  
R.R. Fayzrakhmanov ◽  
O.A. Pavlovsky ◽  
A.V. Sukhanova ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Comparative Analysis ◽  
Anterior Chamber ◽  
Intraocular Lens ◽  
Silicone Oil ◽  
Vitreous Cavity ◽  
Intraocular Lenses ◽  
Silicon Oil ◽  
Group 2 ◽  
Iol Fixation

The purpose of this study is to conduct a comparative analysis of the correction of aphakia by various models of intraocular lenses using silicon oil tamponade (SO) of the vitreous cavity. Materials and methods. The studies were conducted on 16 eyes of patients aged from 56 to 75 years (65.5±12 years) with aphakia and pathology of the vitreal cavity. The duration of the silicone tamponade was 2-3 months. Depending on the use of the type of IOL, all patients were divided into 2 groups. Results. When using an anterior chamber intraocular lens (IOL), the presence of ophthalmic hypertension was revealed in 75% of cases, which is 2.02 times higher than when using transcleral IOL fixation. In 37.5% of cases, the SO output to the anterior chamber is determined, in contrast to the group where IOL hemming was used. A higher percentage of SO migration to the anterior chamber of the eye in group 2 patients is due to a violation of the anatomy of the anterior chamber barrier and the vitreal cavity. Conclusion. Thus, in patients who underwent transcleral IOL fixation, visual acuity is 2.1 times higher than in patients who were implanted with an anterior chamber IOL. Transcleral fixation of the IOL can form the necessary barrier between the anterior and posterior chambers of the eye, and is also the closest IOL position to the physiological one. Key words: intraocular lens, silicone oil, transcleral fixation.

Treatment of the сomplications of long-term silicone oil tamponade in a patient with retinopathy of prematurity and recurrent retinal detachment

2021 ◽  
pp. 367-374
Author(s):  
A. Kolesnik ◽  
◽  
B. Malyugin ◽  
E. Pedanova ◽  
I. Gorshkov ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Retinopathy Of Prematurity ◽  
Silicone Oil ◽  
Combined Treatment ◽  
Corneal Thickness ◽  
Functional Results ◽  
Vitreous Cavity ◽  
Silicone Oil Tamponade ◽  
The Right

Objective. To present the clinical and functional results of combined treatment of the complications of long-term silicone oil tamponade in a patient with retinopathy of premature. Materials and methods. A 24-year-old patient diagnosed with stage 4b retinopathy of premature in a single seeing right eye. Between 2011 and 2020 underwent 5 microinvasive revisions of the vitreous cavity with replacement of silicone oil and median duration of silicone oil tamponade of 19+25.5 months over this entire period. Because of the constant migration of emulsified silicone oil to anterior chamber due to weakness of iridolenticular ligaments, band keratopathy developed in the right eye, opacity of the IOL due to the adhesion of precipitates on its anterior and posterior surfaces, pupillary membrane, and aggravation of the proliferative membrane on the ocular surface. UCVA was proectio incerta and IOP was 17 mmHg. The median thickness of the cornea was 853 μm, the average thickness of the corneal calcifications is 57 μm. The patient underwent revision of the vitreous cavity with removal of the pupillary membrane, the next steps were to install bandage sutures in the anterior chamber parallel to iris in two mutually perpendicular surfaces to create additional barriers to silicone oil migration. Then we used 27 mg of K3-EDTA to produce 0.1% chelating solution and to remove corneal calcium deposits. Final stage was YAG – laser discision of precipitates from the IOL surfaces. Results. Postoperatively UCVA of the right eye in 1-month was 0.05, IOP was 17 mmHg and endothelial cell density was 1200 cells / mm2. According to OCT data the median corneal thickness was 640 μm, the thickness of the epithelial layer was 39 μm. Biomicroscopically, cornea was transparent, a single silicone oil vesicle in the lower segment of anterior chamver, the bandage sutures are consistent, the IOL is centered with a transparent optical zone, silicone oil visualized on the fundus, epi- and subretinal proliferates were delimited by laser coagulates, epiretinal membrane was in the macular region. Key words: retinopathy of prematurity, silicone oil, emulsification, ribbon-like keratopathy, bandage threads, EDTA.

Management of a case of Enhanced S-cone syndrome with massive foveoschisis treated with pars plana vitrectomy with silicone oil tamponade

2021 ◽  
pp. 1-4
Author(s):  
Lorane Bechet ◽  
Raphaël Atia ◽  
Christina Zeitz ◽  
Saddek Mohand-Saïd ◽  
José-Alain Sahel ◽  
...  
Keyword(s):  
Pars Plana Vitrectomy ◽  
Silicone Oil ◽  
Pars Plana ◽  
Silicone Oil Tamponade ◽  
Enhanced S Cone Syndrome

Comparative Surface Imaging Study of Multifocal Diffractive Intraocular Lenses

2021 ◽  
Author(s):  
Hyeck Soo Son ◽  
Jung Min Lee ◽  
Ramin Khoramnia ◽  
Chul Young Choi
Keyword(s):  
Imaging Study ◽  
The Other ◽  
Intraocular Lenses ◽  
Optical Surface ◽  
Diffractive Optic ◽  
Atomic Force ◽  
Acceptable Range ◽  
Different Types ◽  
Concentric Pattern

Abstract Purpose To analyse and compare the surface topography and roughness of three different types of diffractive multifocal IOLs. Methods Using scanning electron microscope (SEM, Inspect F, 5.0 KV, maximum magnification up to 20,000) and atomic force microscope (AFM, Park Systems, XE-100, non-contact, area profile comparison, 10 × 10 µm, 40 × 40 µm), the surface quality of the following diffractive IOLs was studied: the AcrySof IQ PanOptix (Alcon, USA), the AT LARA 829MP (Carl Zeiss Meditec, Germany), and Tecnis Symfony (Johnson&Johnson Vision, USA). The measurements were made over three representative areas (central non-diffractive optic, central diffractive optic, and diffractive step) of each IOL. Roughness profile in terms of mean arithmetic roughness (Ra) and root-mean-squared roughness (Rq) values were obtained and compared statistically. Results In SEM examination, all IOLs showed a smooth optical surface without any irregularities at low magnification. At higher magnification, Tecnis Symfony showed unique highly regular, concentric, and lineate structures in the diffractive optic area which could not be seen in the other studied diffractive IOLs. The differences in the measured Ra and Rq values of the Tecnis Symfony were statistically significant compared to the other models (p < 0.05). Conclusion Various different topographical traits were observed in three diffractive multifocal IOLs. The Ra values of all studied IOLs were within an acceptable range. Tecnis Symfony showed statistically significant higher surface Ra values at both central diffractive optic and diffractive step areas. Furthermore, compared to its counterparts, Tecnis Symfony demonstrated highly ordered, concentric pattern in its diffractive surfaces.

Silicone Oil Injection After Failed Primary Vitreous Surgery in Severe Ocular Trauma

1989 ◽  
Vol 107 (5) ◽  
pp. 537-543 ◽  
Author(s):  
Andrew N. Antoszyk ◽  
Brooks W. McCuen Ii ◽  
Eugene de Juan ◽  
Robert Machemer
Keyword(s):  
Ocular Trauma ◽  
Silicone Oil ◽  
Vitreous Surgery ◽  
Oil Injection
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