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Acta Ophthalmologica Scandinavica Feb 2006The pathogenesis of age-related maculopathy (ARM), the most common cause of visual loss after the age of 60 years, is indeed a complicated scenario that involves a... (Review)
Review
The pathogenesis of age-related maculopathy (ARM), the most common cause of visual loss after the age of 60 years, is indeed a complicated scenario that involves a variety of hereditary and environmental factors. The pathological cellular and molecular events underlying retinal photochemical light damage, including photoreceptor apoptosis, have been analysed in experimental animal models. Studies of age-related alterations of the retina and photoreceptors, the accumulation of lipofuscin in retinal pigment epithelium (RPE) cells, and the formation of drusen have greatly contributed to our knowledge. A new concept of an inflammatory response to drusen has emerged, suggesting immunogenic and systemic reactions in Bruch's membrane and the subretinal space. Oxidative stress and free radical damage also impact on the photoreceptors and RPE cells in the ageing eye. Based on the photoelectric effect, a fundamental concept in quantum physics, the consequences of high-energy irradiation have been analysed in animal models and cell culture. Short-wavelength radiation (rhodopsin spectrum), and the blue light hazard (excitation peak 440 nm), have been shown to have a major impact on photoreceptor and RPE function, inducing photochemical damage and apoptotic cell death. Following cataract surgery, there is a dramatic change in ocular transmittance. In aphakic or pseudophakic eyes (with clear intraocular lenses), high-energy (blue) and ultraviolet-A radiation strikes the retina. Epidemiological data indicate a significantly increased 5-year incidence of late ARM in non-phakic eyes compared with phakic eyes. In recent years, putative prophylactic measures against ARM have emerged. The implantation of 'yellow' intraocular lenses (IOLs) that absorb high-energy blue radiation is, from a theoretical point of view, the most rational approach, and, from a practical point of view, is easy to accomplish. With increasing age, RPE cells accumulate lipofuscin (chromophore A2E). It is noteworthy that the yellow IOL not only protects A2E-laden human RPE cells from blue light (peak 430 nm) damage, but also alleviates the detrimental effects of green (peak 550 nm) and white light. A prophylactic treatment using antioxidants is aimed at counteracting oxidative stress and free radical cellular damage. The Age-Related Eye Disease Study (AREDS), a randomized clinical trial, showed a significantly lower incidence of late ARM in a cohort of patients with drusen maculopathy treated with high doses of antioxidants than in a placebo group. In recent years, considerable progress in retinal research has been achieved, creating a platform for the search for new prophylactic and therapeutic measures to alleviate or prevent photoreceptor and RPE degeneration in ARM.
Topics: Animals; Antioxidants; Aphakia, Postcataract; Free Radicals; Humans; Incidence; Lens Implantation, Intraocular; Lenses, Intraocular; Light; Macular Degeneration; Oxidative Stress; Photoreceptor Cells, Vertebrate; Pseudophakia; Radiation Injuries
PubMed: 16445433
DOI: 10.1111/j.1600-0420.2005.00627.x -
Indian Journal of Ophthalmology Sep 2004Glaucoma is one of the most common causes of visual loss despite successful congenital cataract surgery. The overall incidence does not appear to have decreased with... (Review)
Review
Glaucoma is one of the most common causes of visual loss despite successful congenital cataract surgery. The overall incidence does not appear to have decreased with modern microsurgical techniques. The onset of glaucoma may be acute or insidious and notoriously refractory to treatment. Angle closure glaucoma may occur in the early postoperative period; but the most common type of glaucoma to develop after congenital cataract surgery is open angle glaucoma. Several risk factors have been identified and both chemical and mechanical theories have been proposed for its pathogenesis. Unlike children with congenital glaucoma, those with paediatric glaucoma following congenital cataract surgery are usually asymptomatic despite high intraocular pressure. They may require regular evaluation under anaesthesia, whenever there are any suspicious findings. Unlike congenital glaucoma, the first line of treatment for glaucoma in aphakia/pseudophakia may be medical. Traditional trabeculectomy in paediatric glaucoma following congenital cataract surgery has met with limited success. The addition of antimetabolites to trabeculectomy is known to inhibit fibrosis and enhance the success, but carries the lifelong risk of bleb-related endophthalmitis. Drainage implant surgery is a viable option to achieve longterm intraocular pressure control in this refractory group of patients. Cycloablative procedures may provide temporising treatment and should be reserved for patients with low visual potential. Diagnosis of glaucoma following congenital cataract surgery requires lifelong surveillance and continuous assessment of the problem. Further research is needed to understand the pathophysiology, prevention and treatment of this sight-threatening complication following successful cataract surgery in children.
Topics: Aphakia, Postcataract; Cataract; Cataract Extraction; Glaucoma; Humans; Incidence; India; Pseudophakia
PubMed: 15510457
DOI: No ID Found -
PloS One 2016To assess wavefront derived refraction and full eye biometry including ciliary muscle dimension and full eye axial geometry in pseudophakic eyes using spectral domain...
PURPOSE
To assess wavefront derived refraction and full eye biometry including ciliary muscle dimension and full eye axial geometry in pseudophakic eyes using spectral domain OCT equipped with a Shack-Hartmann wavefront sensor.
METHODS
Twenty-eight adult subjects (32 pseudophakic eyes) having recently undergone cataract surgery were enrolled in this study. A custom system combining two optical coherence tomography systems with a Shack-Hartmann wavefront sensor was constructed to image and monitor changes in whole eye biometry, the ciliary muscle and ocular aberration in the pseudophakic eye. A Badal optical channel and a visual target aligning with the wavefront sensor were incorporated into the system for measuring the wavefront-derived refraction. The imaging acquisition was performed twice. The coefficients of repeatability (CoR) and intraclass correlation coefficient (ICC) were calculated.
RESULTS
Images were acquired and processed successfully in all patients. No significant difference was detected between repeated measurements of ciliary muscle dimension, full-eye biometry or defocus aberration. The CoR of full-eye biometry ranged from 0.36% to 3.04% and the ICC ranged from 0.981 to 0.999. The CoR for ciliary muscle dimensions ranged from 12.2% to 41.6% and the ICC ranged from 0.767 to 0.919. The defocus aberrations of the two measurements were 0.443 ± 0.534 D and 0.447 ± 0.586 D and the ICC was 0.951.
CONCLUSIONS
The combined system is capable of measuring full eye biometry and refraction with good repeatability. The system is suitable for future investigation of pseudoaccommodation in the pseudophakic eye.
Topics: Aged; Aged, 80 and over; Biometry; Female; Humans; Male; Middle Aged; Pseudophakia; Tomography, Optical Coherence
PubMed: 27010674
DOI: 10.1371/journal.pone.0152293 -
Journal of Cataract and Refractive... Apr 2023To compare outcomes in patients who underwent cataract extraction with implantation of nondiffractive extended depth-of-focus (ND-EDOF; Alcon AcrySof Vivity) or neutral... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
To compare outcomes in patients who underwent cataract extraction with implantation of nondiffractive extended depth-of-focus (ND-EDOF; Alcon AcrySof Vivity) or neutral aspheric monofocal (Bausch & Lomb enVista) intraocular lenses (IOLs).
SETTING
Academic medical center.
DESIGN
Prospective single-center double-arm patient- and assessor-masked randomized controlled trial.
METHODS
Patients were randomized to receive either a ND-EDOF or monofocal IOL in both eyes, targeted for emmetropia. Uncorrected and corrected (CDVA) distance visual acuities, distance-corrected intermediate visual acuity (DCIVA), distance-corrected near visual acuity (DCNVA), level of spectacle independence, and severity of photic phenomena were assessed at 3 months postoperatively.
RESULTS
56 patients were enrolled, of which 24 in the ND-EDOF group and 27 in the monofocal group completed follow-up. The binocular mean CDVA, DCIVA, and DCNVA were 20/20, 20/19, and 20/21 for the ND-EDOF IOL and 20/18 ( P = .188), 20/31 ( P < .001), and 20/30 ( P = .004) for the monofocal IOL, respectively. At intermediate, 88% of the ND-EDOF vs 30% of the monofocal patients had a binocular DCIVA of 20/25 or better ( P < .001). Moderate or severe glare occurred in 20.8% of ND-EDOF vs 7.4% of monofocal patients ( P = .228), whereas moderate or severe halos occurred in 16.7% of ND-EDOF vs 11.1% of monofocal patients ( P = .697).
CONCLUSIONS
The ND-EDOF and monofocal IOLs provided similarly excellent distance vision. Patients implanted with the ND-EDOF IOL had 2 more lines of vision at both intermediate and near, and a greater proportion reported spectacle independence. Most patients in both groups reported low severity of photic phenomena.
Topics: Humans; Lens Implantation, Intraocular; Prospective Studies; Phacoemulsification; Patient Satisfaction; Prosthesis Design; Lenses, Intraocular; Patient Reported Outcome Measures; Pseudophakia
PubMed: 36728998
DOI: 10.1097/j.jcrs.0000000000001123 -
The British Journal of Ophthalmology Nov 2008To analyse how age-related losses in crystalline lens transmittance and pupillary area affect circadian photoreception and compare the circadian performance of phakic... (Review)
Review
AIM
To analyse how age-related losses in crystalline lens transmittance and pupillary area affect circadian photoreception and compare the circadian performance of phakic and pseudophakic individuals of the same age.
METHODS
The spectral sensitivity of circadian photoreception peaks in the blue part of the spectrum at approximately 460 nm. Photosensitive retinal ganglion cells send unconscious information about environmental illumination to non-visual brain centres including the human body's master biological clock in the suprachiasmatic nuclei. This information permits human physiology to be optimised and aligned with geophysical day-night cycles using neural and hormonal messengers including melatonin. Age-related transmittance spectra of crystalline lenses and photopic pupil diameter are used with the spectral sensitivity of melatonin suppression and the transmittance spectra of intraocular lenses (IOLs) to analyse how ageing and IOL chromophores affect circadian photoreception.
RESULTS
Ageing increases crystalline lens light absorption and decreases pupil area resulting in progressive loss of circadian photoreception. A 10-year-old child has circadian photoreception 10-fold greater than a 95-year-old phakic adult. A 45-year-old adult retains only half the circadian photoreception of early youth. Pseudophakia improves circadian photoreception at all ages, particularly with UV-only blocking IOLs which transmit blue wavelengths optimal for non-visual photoreception.
CONCLUSIONS
Non-visual retinal ganglion photoreceptor responses to bright, properly timed light exposures help assure effective circadian photoentrainment and optimal diurnal physiological processes. Circadian photoreception can persist in visually blind individuals if retinal ganglion cell photoreceptors and their suprachiasmatic connections are intact. Retinal illumination decreases with ageing due to pupillary miosis and reduced crystalline lens light transmission especially of short wavelengths. Inadequate environmental light and/or ganglion photoreception can cause circadian disruption, increasing the risk of insomnia, depression, numerous systemic disorders and possibly early mortality. Artificial lighting is dimmer and less blue-weighted than natural daylight, contributing to age-related losses in unconscious circadian photoreception. Optimal intraocular lens design should consider the spectral requirements of both conscious and unconscious retinal photoreception.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aging; Child; Circadian Rhythm; Eye Protective Devices; Female; Humans; Lens, Crystalline; Male; Middle Aged; Photoreceptor Cells, Vertebrate; Pseudophakia; Pupil; Refraction, Ocular; Scattering, Radiation; Ultraviolet Rays
PubMed: 18757473
DOI: 10.1136/bjo.2008.141747 -
JAMA Ophthalmology Mar 2022Cataract is an important cause of visual impairment in children. Data from a large pediatric cataract surgery registry can provide real-world estimates of visual...
IMPORTANCE
Cataract is an important cause of visual impairment in children. Data from a large pediatric cataract surgery registry can provide real-world estimates of visual outcomes and the 5-year cumulative incidence of adverse events.
OBJECTIVE
To assess visual acuity (VA), incidence of complications and additional eye operations, and refractive error outcomes 5 years after pediatric lensectomy among children younger than 13 years.
DESIGN, SETTING, AND PARTICIPANTS
This prospective cohort study used data from the Pediatric Eye Disease Investigator Group clinical research registry. From June 2012 to July 2015, 61 eye care practices in the US, Canada, and the UK enrolled children from birth to less than 13 years of age who had undergone lensectomy for any reason during the preceding 45 days. Data were collected from medical record reviews annually thereafter for 5 years until September 28, 2020.
EXPOSURES
Lensectomy with or without implantation of an intraocular lens (IOL).
MAIN OUTCOMES AND MEASURES
Best-corrected VA and refractive error were measured from 4 to 6 years after the initial lensectomy. Cox proportional hazards regression was used to assess the 5-year incidence of glaucoma or glaucoma suspect and additional eye operations. Factors were evaluated separately for unilateral and bilateral aphakia and pseudophakia.
RESULTS
A total of 994 children (1268 eyes) undergoing bilateral or unilateral lensectomy were included (504 [51%] male; median age, 3.6 years; range, 2 weeks to 12.9 years). Five years after the initial lensectomy, the median VA among 701 eyes with available VA data (55%) was 20/63 (range, 20/40 to 20/100) in 182 of 316 bilateral aphakic eyes (58%), 20/32 (range, 20/25 to 20/50) in 209 of 386 bilateral pseudophakic eyes (54%), 20/200 (range, 20/50 to 20/618) in 124 of 202 unilateral aphakic eyes (61%), and 20/65 (range, 20/32 to 20/230) in 186 of 364 unilateral pseudophakic eyes (51%). The 5-year cumulative incidence of glaucoma or glaucoma suspect was 46% (95% CI, 28%-59%) in participants with bilateral aphakia, 7% (95% CI, 1%-12%) in those with bilateral pseudophakia, 25% (95% CI, 15%-34%) in those with unilateral aphakia, and 17% (95% CI, 5%-28%) in those with unilateral pseudophakia. The most common additional eye surgery was clearing the visual axis, with a 5-year cumulative incidence of 13% (95% CI, 8%-17%) in participants with bilateral aphakia, 33% (95% CI, 26%-39%) in those with bilateral pseudophakia, 11% (95% CI, 6%-15%) in those with unilateral aphakia, and 34% (95% CI, 28%-39%) in those with unilateral pseudophakia. The median 5-year change in spherical equivalent refractive error was -8.38 D (IQR, -11.38 D to -2.75 D) among 89 bilateral aphakic eyes, -1.63 D (IQR, -3.13 D to -0.25 D) among 130 bilateral pseudophakic eyes, -10.75 D (IQR, -20.50 D to -4.50 D) among 43 unilateral aphakic eyes, and -1.94 D (IQR, -3.25 D to -0.69 D) among 112 unilateral pseudophakic eyes.
CONCLUSIONS AND RELEVANCE
In this cohort study, development of glaucoma or glaucoma suspect was common in children 5 years after lensectomy. Myopic shift was modest during the 5 years after placement of an intraocular lens, which should be factored into implant power selection. These results support frequent monitoring after pediatric cataract surgery to detect glaucoma, visual axis obscuration causing reduced vision, and refractive error.
Topics: Aphakia; Aphakia, Postcataract; Cataract; Cataract Extraction; Child; Child, Preschool; Cohort Studies; Female; Follow-Up Studies; Glaucoma; Humans; Infant; Lens Implantation, Intraocular; Male; Ocular Hypertension; Prospective Studies; Pseudophakia; Refractive Errors; Vision Disorders; Visual Acuity
PubMed: 35142808
DOI: 10.1001/jamaophthalmol.2021.6176 -
Translational Vision Science &... Aug 2021The purpose of this study was to determine if a battery of polarization-modulated stimuli, quantified as a single metric, is effective in identifying macular disease in...
PURPOSE
The purpose of this study was to determine if a battery of polarization-modulated stimuli, quantified as a single metric, is effective in identifying macular disease in the presence/absence of cataract or pseudophakia.
METHODS
Using a modified liquid crystal display, polarization pattern perception (PPP) for a formulated battery of geometric and logMAR stimuli was evaluated in participants that had either no eye pathology (healthy participants) or were grouped according to the presence of cataract, pseudophakia, and/or age-related macular degeneration (AMD). PPP was quantified as response frequencies to individual stimuli, and as a novel monocular polarization sensitivity score (Ps) based on perception of the stimulus battery set.
RESULTS
Stimulus response frequencies were pattern-dependent and, compared with healthy participants, reduced for cataract and AMD groups but not for subjects with pseudophakia. Compared with healthy eyes (n = 47, median Ps = 17), Ps was significantly reduced by AMD (n = 59, median Ps = 1, P < 0.001) and, to a lesser extent, by cataracts (n = 80, median Ps = 6, P < 0.001). There was no significant difference between Ps for healthy and pseudophakic eyes (n = 47, median Ps = 13, P = 0.323). There was no significant correlation between Ps and logMAR visual acuity.
CONCLUSIONS
In the absence of significant cataract, or in pseudophakia, a set of polarization-modulated visual stimuli, quantified as the Ps score, distinguishes AMD from healthy maculae.
TRANSLATIONAL RELEVANCE
Perception of polarization-modulated stimuli, previously shown to be macula-dependent in a laboratory setting, is effective as a test of macular function in health and disease in a clinic setting.
Topics: Cataract; Humans; Macular Degeneration; Pseudophakia; Refraction, Ocular; Visual Acuity
PubMed: 34351366
DOI: 10.1167/tvst.10.9.8 -
Indian Journal of Ophthalmology 2011There are few studies on pseudophakic monovision even though it is widely applied. We reviewed the published literature on pseudophakic monovision. Surgeons select... (Review)
Review
There are few studies on pseudophakic monovision even though it is widely applied. We reviewed the published literature on pseudophakic monovision. Surgeons select patients who not only have a strong desire to be free of glasses after surgery, but also fully understand monovision design and its drawbacks. However, other criteria adopted for pseudophakic monovision are very different. Both traditional monovision and cross monovision are used in pseudophakic monovision, and the target binocular anisometropia ranges from -1.0 D to -2.75 D. Postoperative results were acceptable in every study and most patients were satisfied, with vision being improved and presbyopia corrected. Complications were decreased stereopsis, contrast sensitivity, and visual fields, similar to other types of monovision. The term "pseudophakic monovision" should include more than just monocular intraocular lens implantation in two eyes, and further studies are required.
Topics: Cataract; Eyeglasses; Humans; Lens Implantation, Intraocular; Presbyopia; Pseudophakia; Vision, Monocular
PubMed: 22011494
DOI: 10.4103/0301-4738.86318 -
Aging Mar 2017Cataract surgery is the most frequently performed surgical procedure worldwide. We aim to determine the prevalence of having implanted an artificial lens (pseudophakia)...
Cataract surgery is the most frequently performed surgical procedure worldwide. We aim to determine the prevalence of having implanted an artificial lens (pseudophakia) and of no lens (aphakia) and to compare visual function.As part of the Gutenberg Health study, a population-based cross-sectional study was conducted in Germany. An ophthalmological examination including slit-lamp examination was conducted. Prevalence including 95% confidential intervals were calculated and analyses were conducted for systemic and ocular associated factors with pseudophakia using multivariable logistic regression models. Vision-related quality of life was assessed using a standardized questionnaire and Rasch transformation.14,696 people were included. Of these, 1.55% [1.36%-1.77%] had unilateral pseudophakia and 3.08% [2.81%-3.37%] had bilateral pseudophakia. Unilateral aphakia was present in 21 people and bilateral aphakia in 2 people. Pseudophakia was independently associated with age, higher body weight and lower body height, diabetes and smoking. Vision-related quality of life values were similar for those with bilateral phakia and pseudophakia but were lower for those with unilateral pseudophakia.The pseudophakia status is related to several cardiovascular risk factors, indicating a relationship to an aging effect that causes premature lens opacification. Bilateral pseudophakia can almost imitate the physiological condition of phakia except for the need to use glasses.
Topics: Adult; Aged; Aphakia, Postcataract; Cardiovascular Diseases; Cross-Sectional Studies; Female; Germany; Humans; Male; Middle Aged; Prevalence; Pseudophakia; Quality of Life; Risk Factors
PubMed: 28358301
DOI: 10.18632/aging.101208 -
The British Journal of Ophthalmology Nov 2018Phacoemulsification has been shown to reduce intraocular pressure (IOP). The mechanism of action is thought to be via increased trabecular outflow facility. However,...
PURPOSE
Phacoemulsification has been shown to reduce intraocular pressure (IOP). The mechanism of action is thought to be via increased trabecular outflow facility. However, studies on the relationship between phacoemulsification and outflow facility have been inconsistent. This study intended to examine the change in electronic Schiotz tonographic outflow facility (TOF) and IOP measurements following phacoemulsification.
METHODS
Patients who were due to undergo a standard clear corneal incision phacoemulsification with intraocular lens (IOL) implantation, at St Thomas' Hospital, were invited to participate in this study. IOP was measured using Goldmann's applanation tonometer, and TOF was measured by electronic Schiotz tonography at baseline and at 3, 6 and 12 months postoperatively.
RESULTS
Forty-one patients were recruited. Tonography data for 27 patients were reliable and available at all time points. Eleven cases had primary open angle glaucoma and cataract, while 16 patients had cataract only. Mean IOP reduced at every time point postoperatively significantly compared with baseline. TOF improved significantly after cataract extraction at all time points (baseline of 0.14±0.06 vs 0.18±0.09 at 3 months, P=0.02 and 0.20±0.09 at 6 months, P=0.003, 0.17±0.07 µL/min mmHg at 12 months, P=0.04). Five contralateral eyes of patients with cataracts only who did not have any intraocular surgery during the follow-up period were used as comparison. Their IOP and TOF did not change significantly at any postoperative visits.
CONCLUSION
This is the first study using electronic Schiotz tonography with documented anterior chamber depth and gonioscopy after modern cataract surgery (CS) with phacoemulsification and IOL implantation. We demonstrated that phacoemulsification increases TOF and this fully accounts for the IOP reduction following CS.
ISTCRN REGISTRATION NUMBER
ISRCTN04247738.
Topics: Adult; Aged; Aged, 80 and over; Aqueous Humor; Cataract; Female; Glaucoma, Open-Angle; Gonioscopy; Humans; Intraocular Pressure; Lens Implantation, Intraocular; Male; Middle Aged; Phacoemulsification; Prospective Studies; Pseudophakia; Slit Lamp Microscopy; Tonometry, Ocular; Visual Acuity
PubMed: 29654113
DOI: 10.1136/bjophthalmol-2017-311548