Effect of Intraocular Lens Tilt and Decentration on Visual Acuity, Dysphotopsia and Wavefront Aberrations

Tilt and decentration of intraocular lenses (IOL) may occur secondary to a complicated cataract surgery or following an uneventful phacoemulsification. Although up to 2–3° tilt and a 0.2–0.3 mm decentration are common and clinically unnoticed for any design of IOL, larger extent of tilt and decentration has a negative impact on the optical performance and subsequently, the patients’ satisfaction. This negative impact does not affect various types of IOLs equally. In this paper we review the methods of measuring IOL tilt and decentration and focus on the effect of IOL tilt and decentration on visual function, in particular visual acuity, dysphotopsia, and wavefront aberrations. Our review found that the methods to measure the IOL displacement have significantly evolved and the available studies have employed different methods in their measurement, while comparability of these methods is questionable. There has been no universal reference point and axis to measure the IOL displacement between different studies. A remarkably high variety and brands of IOLs are used in various studies and occasionally, opposite results are noticed when two different brands of a same design were compared against another IOL design in two studies. We conclude that <5° of inferotemporal tilt is common in both crystalline lenses and IOLs with a correlation between pre- and postoperative lens tilt. IOL tilt has been noticed more frequently with scleral fixated compared with in-the-bag IOLs. IOL decentration has a greater impact than tilt on reduction of visual acuity. There was no correlation between IOL tilt and decentration and dysphotopsia. The advantages of aspheric IOLs are lost when decentration is >0.5 mm. The effect of IOL displacement on visual function is more pronounced in aberration correcting IOLs compared to spherical and standard non-aberration correcting aspherical IOLs and in multifocal versus monofocal IOLs. Internal coma has been frequently associated with IOL tilt and decentration, and this increases with pupil size. There is no correlation between spherical aberration and IOL tilt or decentration. Although IOL tilt produces significant impact on visual outcome in toric IOLs, these lenses are more sensitive to rotation compared to tilt.

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Visual Function and Subjective Quality of Life in Chinese Cataract Patients after Implantation with Aspheric Intraocular Lenses

European Journal of Ophthalmology ◽

10.5301/ejo.2011.6441 ◽

2011 ◽

Vol 21 (6) ◽

pp. 732-740

Author(s):

Yanwen Fang ◽

Yi Lu ◽

Xinhua Wu ◽

Aizhu Miao ◽

Yi Luo

Keyword(s):

Visual Acuity ◽

Contrast Sensitivity ◽

Visual Function ◽

Spherical Aberration ◽

Visual Quality ◽

Intraocular Lenses ◽

Subjective Quality Of Life ◽

Significant Difference ◽

The Mean ◽

Cataract Patients

Purpose. To evaluate and compare the objective and subjective visual function after implantation of 2 aspheric intraocular lenses (IOLs) in Chinese cataract patients. Methods. Forty-one eyes of 28 patients with cataract were randomly assigned to receive either the MC X11 ASP IOL or the AcrySof IQ IOL. Three months postoperatively, best-corrected visual acuity (BCVA), contrast sensitivity, wavefront aberrations, and subjective visual quality were measured. The degree of posterior capsule opacification (PCO) was recorded at last follow-up. Results. Postoperative mean monocular BCVA was 0.05±0.13 logMAR in the MC X11 group and 0.05±0.08 logMAR in the IQ group. There was no significant difference in visual acuity, contrast sensitivity, subjective visual quality, and degree of PCO between the 2 groups. For a 6-mm pupil diameter, the mean spherical aberration (Z40) was 0.075±0.076 μm in the MC X11 group and 0.056±0.111 μm in the IQ group. However, 45.5% and 57.9% of the eyes in the MC X11 and IQ groups had values >0.10 μm, respectively. The mean RMS values of the high-order aberrations were similar between the 2 groups except the higher fifth- and sixth-order aberrations, which were significantly higher in the MC X11 group. Conclusions. Both IOLs provided similar and good visual outcomes. However, the data suggest that the amount of negative spherical aberration generated by current available aspheric IOLs might not be optimal for Chinese eyes.

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Prognostic factors for postoperative visual outcome in surgically treated suprasellar meningiomas

Medicinski pregled ◽

10.2298/mpns1606146g ◽

2016 ◽

Vol 69 (5-6) ◽

pp. 146-152 ◽

Cited By ~ 2

Author(s):

Desanka Grkovic ◽

Sofija Davidovic

Keyword(s):

Visual Acuity ◽

Tumor Size ◽

Visual Function ◽

Tumor Resection ◽

Visual Outcome ◽

Duration Of Symptoms ◽

Postoperative Visual Acuity ◽

Preoperative Visual Acuity ◽

History Of ◽

Meningioma Surgery

Introduction. The prognosis of postoperative visual acuity in patients with surgically treated suprasellar meningiomas is influenced not only by the size and precise localization of meningiomas in the optochiasmatic region and their compressive effect, but also by certain parameters, such as the age of patient, duration of symptoms, and preoperative visual acuity. The purpose of this study was to analyze the influence of these factors on postoperative visual acuity in the patients with surgically treated optochiasmatic meningioma as well as to determine their prognostic value in the recovery of visual function after surgery. Material and Methods. The study sample consisted of 43 patients operated for suprasellar meningioma. All tumors were diagnosed by computed tomography or nuclear magnetic resonance scans. Visual acuity was analyzed both before surgery and six months after surgery. The effects of age, preoperative visual loss, duration of visual symptoms and tumor size on visual outcome were analyzed. Results. Postoperative improvement of visual acuity was observed in 50% of eyes (68.4% of patients). Visual outcome was better in the younger patients. The patients with better preoperative visual acuity had better postoperative visual acuity outcome. Chances of achieving better postoperative visual function and favorable tumor resection outcome were inversely proportional to the increased length of history of disease and tumor size. Conclusion. Postoperative visual acuity prognosis in suprasellar meningioma surgery was favorably affected by the mean duration of symptoms of less than 24 months, tumor size less than 30 mm, and preoperative visual acuity loss below 0.1.

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Small Incision Lenticule Extraction (SMILE) for Moderate and High Myopia: Seven-Year Outcomes of Refraction, Corneal tomography and Wavefront Aberrations

10.21203/rs.2.15558/v1 ◽

2019 ◽

Author(s):

Fei Xia ◽

Yang Shen ◽

Tian Han ◽

Jing Zhao ◽

Hai-Peng Xu ◽

...

Keyword(s):

Visual Acuity ◽

Spherical Aberration ◽

Case Series ◽

Final Visit ◽

Small Incision Lenticule Extraction ◽

Wavefront Aberrations ◽

Distance Visual Acuity ◽

Small Incision ◽

Uncorrected Distance Visual Acuity ◽

Lenticule Extraction

Abstract Background To investigate the long-term corneal stability and wavefront aberrations after small incision lenticule extraction (SMILE) for moderate and high myopia.Methods Prospective, non-consecutive case series. A total of 26 patients (42 eyes) who underwent SMILE from May 2010 to March 2013 at the Fudan University Eye and ENT Hospital (Shanghai, China) were enrolled. The periods of follow-up were 1 month, 1 year, 5 years and 7 years after surgery. The routine eye examinations included uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), manifest refraction and corneal topography.Results All surgeries were executed without any complications. At the final visit, a UDVA of 20/20 or better was achieved in 42 eyes (100%), 21 eyes (50%) exhibited no change in CDVA. 15 eyes (36%) gained one line, 6 eyes (14%) gained two lines, and no eyes lost CDVA lines. 93% and 100% of eyes were within ±0.5 D and ±1.00 D of the target refraction, respectively. A mean refractive regression of -0.17 D was observed between 1 month and 7 years postoperatively. Mean corneal front curvature (KMF) were significantly increased between pre- and post-SMILE surgery (P<0.0001). Higher-order aberrations (HOAs) and vertical coma were significantly increased after SMILE compared to those measured before surgery (all P<0.001). There were no significant differences in horizontal coma, trefoil and spherical aberration between pre- and post-SMILE surgery (all P>0.05).Conclusions SMILE is an effective, safe and stable procedure for myopia correction, with relatively constant corneal stability and wavefront aberrations.

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Prospective analysis of visual function changes in patients with dermatochalasis after upper eyelid blepharoplasty

European Journal of Ophthalmology ◽

10.1177/1120672119857501 ◽

2019 ◽

Vol 30 (5) ◽

pp. 978-984

Author(s):

Meryem Altin Ekin ◽

Seyda Karadeniz Ugurlu

Keyword(s):

Visual Acuity ◽

Contrast Sensitivity ◽

Visual Function ◽

Spherical Aberration ◽

Higher Order ◽

Rank Test ◽

Higher Order Aberrations ◽

Upper Eyelid ◽

Spatial Frequencies ◽

The Difference

Objective: To evaluate the changes of visual acuity, contrast sensitivity, astigmatism, and higher order aberrations after blepharoplasty in patients with dermatochalasis. Methods: Two hundred six eyelids of 103 patients with dermatochalasis were prospectively studied. Visual acuity, contrast sensitivity, corneal topography, astigmatism degree, and higher order aberrations were examined and recorded before and at 1 month after upper eyelid blepharoplasty. Change in contrast sensitivity and astigmatism values were determined according to margin reflex distance of patients, which were classified into three following groups: <2 mm, 2–3 mm, and ⩾ 4 mm. A Wilcoxon signed rank test was performed to compare the difference. Results: No significant differences were observed for visual acuity (p = 0.157). The contrast sensitivity of patients significantly increased at all spatial frequencies both under glare and nonglare conditions (p < 0.05). The mean refractive astigmatism significantly decreased from ‒1.01 ± 1.3 to ‒0.79 ± 0.71, postoperatively (p = 0.029). In patients with marginal reflex distance < 2 mm, mean contrast sensitivity was increased (p < 0.001) and mean astigmatism was decreased significantly (p < 0.001) compared with those with ⩾ 2 mm. Higher order aberrations decreased significantly from 0.62 ± 0.41 µm to 0.55 ± 0.38 µm (p = 0.038) after blepharoplasty. Root mean square of the vertical trefoil (p = 0.038), vertical coma (p = 0.002), horizontal trefoil (p = 0.027), third-order aberration (p = 0.005), secondary vertical stigmatism (p = 0.001), spherical aberration (p = 0.023), secondary horizontal astigmatism (p = 0.002), fourth-order aberration (p = 0.024), vertical pentafoil (p = 0.015), secondary horizontal coma (p = 0.035), secondary horizontal trefoil (p = 0.030), and horizontal pentafoil (p = 0.048) were decreased significantly. Conclusion: Upper eyelid blepharoplasty in patients with dermatochalasis has a significant improvement in visual function in terms of contrast sensitivity, astigmatism, and higher order aberrations.

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Ocular wavefront aberrations in acute central serous chorioretinopathy

Journal of Research in Clinical Medicine ◽

10.34172/jrcm.2021.033 ◽

2021 ◽

Vol 9 (1) ◽

pp. 33-33

Author(s):

Banafsheh Kharrazi Ghadim ◽

Nazli Taheri ◽

Mohammad Reza Niyousha

Keyword(s):

Visual Acuity ◽

Root Mean Square ◽

Central Serous Chorioretinopathy ◽

Spherical Aberration ◽

Optical Parameters ◽

Average Height ◽

Mean Square ◽

Pupillary Dilation ◽

Foveal Thickness ◽

Wavefront Aberrations

Background: Central serous chorioretinopathy (CSCR) is a condition of choroidal and retinal pathologies that may affect vision, so we assessed vision by the ocular wavefront in the acute form of CSCR. Methods: This cross-sectional study included 21 cases (16-male, 5-female) of acute onset CSCR was referred to the retina clinic of Nikookari Eye Hospital. Visual acuity and ocular examination with and without pupillary dilation record. Central macular thickness and sub-foveal fluid height of all patients measured by spectral-domain optical coherence tomography (SD-OCT). All of them fulfilled binocular visual function analyzer by Tracy Technology after complete pupillary dilation. The items such as spherical equivalent, total root mean square, total lower-order aberration, total higher-order aberration, defocus, astigmatism, secondary astigmatism, coma, spherical aberration, trefoil, Strehl ratio in point spread function, the average height in the modulation transfer function, and root mean square error registered. Generalized Estimation Equations (GEE) were used to compare two groups of affected CSCR and normal contralateral eyes. Results: The mean uncorrected distance visual acuity in the CSCR eyes is (Decimal Notation) 0.82±0.17 and in the contralateral eyes is 0.95±0.09 (P=0.002). Analysis of macular OCT data CSCR group represents: central foveal thickness 485.9±165.12 μm and mean fluid height 284.3±165.42 μm. The mentioned optical parameters of ocular wavefront aberrations do not have significantly different results in the two groups. Conclusion: Our study showed CSCR reduced uncorrected visual acuity but it did not detect significant ocular wavefront changes in acute CSCR

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Influence of Angle Alpha on Visual Quality after Implantation of Extended Depth of Focus Intraocular Lenses

10.21203/rs.3.rs-257390/v1 ◽

2021 ◽

Author(s):

Miaomiao Qin ◽

Min Ji ◽

Tianqiu Zhou ◽

Yurong Yuan ◽

Jiawei Luo ◽

...

Keyword(s):

Visual Acuity ◽

Spherical Aberration ◽

Visual Quality ◽

Intraocular Lenses ◽

Patient Questionnaire ◽

Modulation Transfer ◽

Depth Of Focus ◽

Extended Depth Of Focus ◽

Postoperative Changes ◽

Angle Alpha

Abstract Background: To assess postoperative changes in angle alpha, and to evaluate the postoperative visual quality of patients with different angle alpha values after implantation of extended depth of focus (EDOF) intraocular lenses (IOLs).Methods: Seventy-nine eyes of 79 patients who had phacoemulsification with EDOF IOLs implantation were enrolled. A cut-off value of 0.3 mm, 0.4 mm, and 0.5 mm in preoperative angle alpha was chosen to divide eyes into groups. Distance, intermediate, and near visual acuities, modulation transfer function (MTF), and aberrations were recorded during a 6-month follow-up. A patient questionnaire was completed. Results: There were no significant differences in angle alpha postoperatively compared to preoperatively. No significant differences were found in visual acuity and MTF between all groups. With 5mm pupil diameter, there were significant differences of higher-order aberrations and spherical aberration in ocular aberration and internal aberration between angle alpha＜0.4 mm and angle alpha≥ 0.4 mm. Additionally, significant differences of coma were also added in cut-off value of 0.5 mm. When the value of angle alpha is 0.4 mm or higher, there were significant differences in the score of halos and glare.Conclusions: Angle alpha did not affect visual acuity, but the value of 0.4 mm or higher in angle alpha affected the visual quality under scotopic conditions and occurrence of halos and glare. For patients with 0.4 mm or higher in angle alpha, the decision to implant a EDOF IOL should be carefully considered.

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Sutureless retropupillary iris claw intraocular lens implantation is a viable option in aphakic patients

International Journal of Community Medicine and Public Health ◽

10.18203/2394-6040.ijcmph20195880 ◽

2019 ◽

Vol 7 (1) ◽

pp. 350

Author(s):

Neepa R. Gohil ◽

Sandeep Kumar Yadav ◽

Kaumudi Shinde

Keyword(s):

Visual Acuity ◽

Intraocular Lens ◽

Visual Outcome ◽

Good Alternative ◽

Intraocular Lenses ◽

Intraocular Lens Implantation ◽

Visual Rehabilitation ◽

Lens Implantation ◽

Iris Claw Lens ◽

Iris Claw

Visual rehabilitation in aphakia has been a challenge with a wide variety of surgical options available for ophthalmologist. We report the visual outcome with retropupillary iris claw lens secondary to intra operative complications and secondary implantation in aphakia. An interventional study on 4 eyes of 4 patients was conducted. Preoperative visual acuity, slit lamp examination and fundus examination were carried out. Anterior vitrectomy and retropupillary fixation of iris claw lens were done. The primary outcome measure was best-corrected visual acuity and secondary postoperative complication was recorded at various intervals. All patients had visual acuity of ≥6/18 postoperatively. Sutureless retropupillary iris claw intraocular lens implantation is a good alternative of scleral-fixated intraocular lenses in aphakic patients.

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Proportion of Non-Compliance and Factors Affecting It in Children Undergoing Occlusion Therapy for Amblyopia

Journal of Evidence Based Medicine and Healthcare ◽

10.18410/jebmh/2020/589 ◽

2020 ◽

Vol 7 (48) ◽

pp. 2879-2884

Author(s):

Pravitha M. Kumar ◽

Naina Jabeen Hyder ◽

Shaji A ◽

Sunil M.S ◽

Pappa P

Keyword(s):

Visual Acuity ◽

Negative Impact ◽

Visual Outcome ◽

Learning Ability ◽

Final Visual Acuity ◽

Cross Sectional ◽

Factors Affecting ◽

Occlusion Therapy ◽

Study Results

BACKGROUND The term amblyopia literally means dullness of vision. It is defined as unilateral or bilateral reduction of visual acuity due to pattern vision deprivation or abnormal binocular interaction for which no ocular causes can be detected by ocular examination and can be reversed by therapeutic measures. The study was undertaken to estimate the proportion of non-compliance and factors affecting it in children undergoing occlusion therapy for amblyopia. METHODS The study was designed as a hospital based cross sectional study. Children aged 5 - 12 years undergoing occlusion therapy for amblyopia due to strabismus, anisometropia or both, who had been prescribed occlusion for a period of minimum 3 months were included in the study. Children with developmental or neurological disorders and other ocular conditions causing visual impairment, whose parents were not willing to participate in the study or follow up, and uncooperative children were also excluded from the study. RESULTS 52.5 % were non-compliant to occlusion therapy, 31.1 % were partially compliant and only 16.4 % were compliant. 38.5 % had final visual acuity in the range of 6 / 60 - 6 / 24 and 6 / 18 – 6 / 12, 20 % had 6 / 9 - 6 / 6. Different variables were assessed against compliance to check for any association. Significant association was found between compliance to occlusion and socioeconomic status (p = .006), visual acuity at presentation (p = .026), type of amblyopia (p = .038) and final visual acuity (p < .01) and association with educational status were found to be borderline (p = .059). CONCLUSIONS Occlusion therapy for amblyopia is a long drawn process which needs strict compliance and regular follow up. Compliance is a major factor affecting final visual outcome. Poor compliance leads to unsuccessful amblyopia therapy which in turn can have negative impact on child’s learning ability and psychosocial wellbeing. For this reason it is critical that care givers leave the clinic with clear knowledge of how and why patching is being recommended and its importance in improving child’s vision. KEYWORDS Amblyopia, Occlusion, Compliance

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Changes of anthropometric parameters of an eye during the implantation of toric intraocular lenses in children with congenital cataracts.

Modern technologies in ophtalmology ◽

10.25276/2312-4911-2021-2-101-104 ◽

2021 ◽

pp. 101-104

Author(s):

A.I. Shilov ◽

◽

K.K. Shefer ◽

Keyword(s):

Visual Acuity ◽

Cataract Surgery ◽

Intraocular Lenses ◽

Pediatric Cataract ◽

Congenital Cataracts ◽

Positive Effects ◽

Postoperative Astigmatism ◽

Toric Iols ◽

Significant Difference ◽

Pediatric Cataract Surgery

Aim. The aim of the study is to examine changes in the anthropometric and refractive parameters of the eyeball in children with congenital cataracts who have been implanted with various types of IOLs (toric or classic monofocal). Materials and methods. In this work, we retrospectively studied the medical history of 34 children (42 eyes) aged 4 to 15 years, who underwent phacoemulsification of congenital cataracts with implantation of various types of IOLs: toric and simple monofocal. Further, in these groups, by statistical methods, the dynamics of refraction in the first three years after the operation, the incidence of postoperative astigmatism, and its dynamics were assessed. We also assessed the rate of change in the anteroposterior axis of the eyeball, the dynamics of refraction in terms of the total spheroequivalent and maximum visual acuity in 3 years after the operation. Results. According to the results of the study, it was shown that toric IOLs significantly better stimulate the process of emmetropization of the eyeball, and also have a significant tendency to completely eliminate postoperative astigmatism, within 3 years after surgery. However, there were no significant differences in maximally corrected visual acuity between the 2 compared groups. There were also no data showing a significant difference in the more frequent development of myopia in the group receiving the toric IOL. Conclusion. The correct choice and calculation of the IOL remains one of the most difficult tasks in pediatric cataract surgery. New technologies are introduced annually and require constant testing. In this study, we have shown the possibility of using toric IOLs and their positive effects in pediatric cataract surgery and in the prevention and treatment of obscuration amblyopia. Key words: pediatric cataract, intraocular lenses, myopia, refraction, phacoemulsification, amblyopia.

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Functional visual acuity after implantation of diffractive extended depth-of-focus intraocular lenses using an echelett optics

BMC Ophthalmology ◽

10.1186/s12886-021-02189-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Toshihiro Sakisaka ◽

Keiichiro Minami ◽

Keita Takada ◽

Yosai Mori ◽

Kazunori Miyata

Keyword(s):

Visual Acuity ◽

Contrast Sensitivity ◽

Visual Function ◽

Case Series ◽

Intraocular Lenses ◽

Depth Of Focus ◽

Mean Response Time ◽

Extended Depth Of Focus ◽

Functional Visual Acuity ◽

The Mean

Abstract Background The prospective comparative case series aimed to evaluate all-distance visual acuity, contrast sensitivity, and functional visual acuity (FVA) of eyes with diffractive extended depth-of-focus (EDOF) intraocular lenses (IOLs) using an echelett optics and monofocal IOLs with the same platform. Methods Diffractive EDOF and monofocal IOLs were implanted in 27 eyes of 27 patients each. At 3 months after implantation, all-distance visual acuities at distances of 0.3, 0.5, 0.7, 1, 2, 3, and 5 m were measured under distance-corrected. Static visual function was also examined using photopic contrast sensitivity and area under the logarithmic contrast sensitivity function (AULCSF). Dynamic visual function was examined with FVA, and mean FVA value, visual maintenance ratio (VMR), mean response time, and number of blinks were evaluated. These outcomes were compared between the two IOLs. Results The mean distance-corrected visual acuities were better at distances of 0.7 m or nearer in eyes with EDOF IOLs. There was no difference in the contrast sensitivities (P > 0.22). In the FVA results, no difference was found in mean FVA and VMR (P > 0.68). Conclusion The static and dynamic evaluations of postoperative visual functions demonstrated that the visual function of eyes with EDOF IOLs under photopic and distance-corrected conditions was comparable to eyes with monofocal IOLs.

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