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Discover the most talked about and latest scientific content & concepts.

Concept: Presbyopia

168

We present an overview of currently available toric intraocular lenses (IOLs) and multifocal toric IOLs. Relevant patient selection criteria, IOL calculation issues, and surgical techniques for IOL implantation are discussed. Clinical outcomes including uncorrected visual acuity, residual refractive astigmatism, and spectacle independency, which have been reported for both toric IOLs and multifocal toric IOLs, are reviewed. The incidence of misalignment, the most important complication of toric IOLs, is determined. Finally, future developments in the field of toric IOLs are discussed. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Concepts: Ophthalmology, Lens, Presbyopia, Contact lens, Refractive error, Intraocular lens, Cataract, Toric lens

151

We performed a systematic review and meta-analysis to evaluate the benefit and harms associated with implantation of toric intraocular lenses (IOLs) during cataract surgery. Outcomes were postoperative uncorrected distance visual acuity (UCDVA) and distance spectacle independence. Harms were evaluated as surgical complications and residual astigmatism.

Concepts: Medicine, Surgery, Visual acuity, Ophthalmology, Presbyopia, Intraocular lens, Cataract, Toric lens

141

To examine the prevalence of glaucomatous optic neuropathy (GON) in a medium myopic to highly myopic group of patients and its association with parapapillary gamma zone and parapapillary delta zone.

Concepts: Optics, Glaucoma, Ophthalmology, Myopia, Lens, Presbyopia, Optic nerve, ARIA Charts

28

Purpose: To evaluate the outcome, intraoperative and postoperative complications of refractive lens exchange (RLE) by phacoemulsification with posterior chamber intraocular lens (IOL) implantation combined with simultaneous pars plana vitrectomy (PPV) in the management of high myopia. Methods: This prospective study consisted of 45 eyes of 26 patients with preoperative myopia greater than -12.5 dpt. Clear lens phacoemulsification with IOL implantation surgery was combined with PPV. Main outcome measures were best-corrected visual acuity (BCVA), stability of the spherical equivalent (SE) and complications at follow-up. Results: The combined procedure of clear lens phacoemulsification combined with PPV has a favorable outcome with acceptable SE predictability and improvement in BCVA. The postoperative BCVA was 0.67 ± 0.21 compared to 0.15 ± 0.10 preoperatively (p < 0.001). The mean postoperative SE was -1.6 ± 0.9 dpt, showing a significant difference when compared with a mean value of -20.0 ± 5.2 dpt before the operation (p < 0.001). During the follow-up, all IOLs were placed stably in the bag with no capsular tear occurring and only 1 case (2.2%) developed retinal detachment. Conclusion: RLE and implantation of an IOL combined with simultaneous PPV is a reasonable refractive surgery option for middle-aged patients with high myopia.

Concepts: Retina, Ophthalmology, Vitrectomy, Myopia, Lens, Presbyopia, Contact lens, Intraocular lens

28

PURPOSE: To assess the repeatability and accuracy of optical biometry (Lenstar LS900 optical low-coherence reflectometry [OLCR] and IOLMaster partial coherence interferometry [PCI]) and applanation ultrasound biometry in highly myopic eyes. SETTING: Division of Preventive Ophthalmology, Zhongshan Ophthalmic Center, Guangzhou, China. DESIGN: Comparative evaluation of diagnostic technology. METHODS: Biometric measurements were taken in highly myopic subjects with a spherical equivalent (SE) of -6.00 diopters (D) or higher and an axial length (AL) longer than 25.0 mm. Measurements of AL and anterior chamber depth (ACD) obtained by OLCR were compared with those obtained by PCI and applanation A-scan ultrasound. Right eyes were analyzed. Repeatability was evaluated using the coefficient of variation (CoV) and agreement, using Bland-Altman analyses. RESULTS: The mean SE was -11.20 D ± 4.65 (SD). The CoVs for repeated AL measurements using OLCR, PCI, and applanation ultrasound were 0.06%, 0.07%, and 0.20%, respectively. The limits of agreement (LoA) for AL were 0.11 mm between OLCR and PCI, 1.01 mm between OLCR and applanation ultrasound, and 1.03 mm between PCI and ultrasound. The ACD values were 0.29 mm, 0.53 mm, and 0.51 mm, respectively. These repeatability and agreement results were comparable in eyes with extreme myopia (AL ≥27.0 mm) or posterior staphyloma. The mean radius of corneal curvature was similar between OLCR and PCI (7.66 ± 0.24 mm versus 7.64 ± 0.25 mm), with an LoA of 0.12 mm. CONCLUSION: Optical biometry provided more repeatable and precise measurements of biometric parameters, including AL and ACD, than applanation ultrasound biometry in highly myopic eyes. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Concepts: Cornea, Ophthalmology, Accuracy and precision, Myopia, Refractive surgery, Presbyopia, Eyeglass prescription, Staphyloma

28

BACKGROUND: Cataracts are a common and significant cause of visual impairment globally. We aimed to evaluate uncorrected distance visual acuity (UDVA) as an outcome in treating astigmatic cataract patients to assist clinicians or ophthalmologists in their decision making process regarding available interventions. RESULTS: The systematic review identified 11 studies which reported UCVA. All 11 studies reported UDVA. Four brands of toric intraocular lenses (IOLs) were reported in these studies. All studies identified in the literature search reported improvements in UDVA following surgical implant of a toric IOL. The largest improvements in VA were reported using the Human Optics MicroSil toric IOL (0.74 LogMAR, UDVA) and the smallest improvements were also reported using the Human Optics MicroSil toric IOL (0.23 LogMAR, UDVA) in a different study. CONCLUSIONS: The results of this systematic review showed the aggregate of studies reporting a beneficial increase in UDVA with the use of toric IOLs in cataract patients with astigmatism.

Concepts: Decision making, Visual acuity, Ophthalmology, Presbyopia, Intraocular lens, Eye surgery, Cataract

27

Comparison between treatment with wavefront optimized and custom-Q laser-assisted in situ keratomileusis (LASIK) ablations. Our study included 400 eyes of 200 patients divided into two equal groups. All patients were treated for myopia and myopic astigmatism with LASIK. The first group was treated with wavefront optimized ablation and the second group with custom-Q ablation. They were examined preoperatively and postoperatively to assess asphericity, image quality, and other classical outcome parameters. The wavefront optimized ablation group comprised 200 eyes with a mean spherical equivalent refraction (SE) of -5.2188 diopters (D) (range: -1.15 to -10.50 D); the mean Q-value changed from 0.30 preoperatively to 0.06 postoperatively. The custom-Q ablation group also comprised 200 eyes with a mean SE of -5.1575 D (range: -1.35 to -9.00 D); the mean Q-value changed from 0.32 preoperatively to 0.03 postoperatively. A statistically significant difference in postoperative change in Q-values (P = 0.02) and in postoperative visual acuity (P = 0.42) between the two groups was noted. There was no difference between the two groups regarding refractive correction. There was a marginally significant change in BSCVA (best spectacle-corrected visual acuity) between the two groups, and less impairment in the corneal asphericity in the custom-Q group.

Concepts: Ophthalmology, Refractive surgery, Lens, Presbyopia, Eyeglass prescription, Contact lens, Refractive error, Hyperopia

27

To compare preoperative methods for calculating intraocular lens (IOL) power versus the intraoperative wavefront aberrometer in eyes with a history of refractive surgery.

Concepts: Optics, Cornea, Lens, Presbyopia, Intraocular lens

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OBJECTIVE: To evaluate the delivery characteristics of the AcrySof IQ SN60WS intraocular lens (IOL) injected via a preloaded AcrySert delivery system. DESIGN: Prospective observational case series. METHODS: setting: This study was carried out in the cataract service of an ophthalmic hospital that serves a large sector of inner-city London. patient population: The study included all patients undergoing routine phacoemulsification procedures with implantation of the SN60WS IOL via the preloaded system over 5 consecutive months. A total of 85 patients (85 eyes) were included in this study. intervention: Phacoemulsification procedures conducted by 7 surgeons were digitally captured. outcome measures: Video recordings of the IOL delivery stage were analyzed by a single observer. Of particular interests were the orientation of the leading haptic and optic on insertion, the degree of intrawound manipulation of the injector, and the time required to satisfactorily deliver the IOL into the capsular bag in a correct orientation. Problems of IOL delivery were also noted. RESULTS: In 38 out of 85 eyes (45%), correct IOL delivery behavior was achieved with the leading haptic orientating to the left of the surgeon and thus did not require any intrawound rotational manipulation of the injector. Forty-seven of the 85 eyes (55%) required additional rotational manipulation of IOL orientation. Other problems recorded were trapped trailing haptic, haptic-optic adhesion, overriding of the plunger over the optic, and trauma to optic edge. The average time to achieve satisfactory IOL position was 47 seconds. IOL power and the grade of the operating surgeon did not appear to influence the event of a misdirected leading haptic. CONCLUSIONS: The AcrySof SN60WS/AcrySert system does not appear to meet the expectations of pro-viding a predictable means of IOL delivery.

Concepts: Hospital, Physician, Ophthalmology, Lens, Presbyopia, Intraocular lens, Cataract, The Delivery

27

Objective evaluation of accommodation with a bilateral accommodating intraocular lens (IOL) versus monofocal IOLs.

Concepts: Lens, Presbyopia, Intraocular lens, Aphakia