Monocular Aphakia Research Articles

The use of rigid gas permeable contact lens in managing severe anisometropia caused by monocular aphakia following retinal reattachment surgery and high myopia in a 13 year old girl: a case report

Anisometropia if not treated accordingly may cause other issues especially in developing pediatric eyes. This case is a 13 year old female presented with chief complaint of headache and double vision upon wearing prescribed spectacles. Patient had history of high myopia on both eye, amblyopia and spontaneous rhegmatogenous retinal detachment on the left eye. Retinal reattachment and lensectomy surgery were conducted to correct the problem. The surgery was performed without intra ocular lens (IOL) implantation, which left her left eye become high hyperope due to aphakia. Patient was treated with RGP CLs. Final best visual acuity with EDTRS chart was 6/48 on both eyes. Patient reported subjective visual improvement, no headache or double vision.

Asymmetric maculopathy with mutations in adenosine triphosphate-binding cassette, sub-family A, member 4 and jagged canonical notch ligand 1 after 30 years of monocular aphakia

We report an unusual case of asymmetric maculopathy in a patient with a 30-year history of monocular aphakia. An 82-year old man presented with unexplained visual loss in his right eye. Examination revealed loss of the ellipsoid zone, abnormal visual fields, and multifocal electroretinogram, all worse in the right eye. Suspecting a genetic predisposition to maculopathy that may have been exacerbated by the asymmetric media, we conducted genetic testing that revealed mutations in adenosine triphosphate-binding cassette, sub-family A, member 4 (ABCA4) and jagged canonical notch ligand 1 (JAG1). This case shows that a genetic predisposition toward maculopathy may be exacerbated by extraretinal factors, including the asymmetric phakic status of the eyes.

Contact lens fitting in nonamblyopigenic anisometropia secondary to monocular aphakia caused by ocular trauma

Anisometropia is characterized by difference between the refractive errors of the eyes and can be classified into refractive and axial. Aniseikonia is one of the possible consequences of anisometropias. As a general rule, aniseikonia tends to be less significant when we correct axial anisometropias with spectacles and refractive anisometropias with contact lens. One of the possible causes of refractive anisometropias is aphakia, which can be a result of ocular trauma. Amblyopia is a visual neurological disorder characterized by inadequate consolidation of visual acuity, due to insufficient visual stimulation. We present a case of contact lens fitting in a patient with significant difference in axial length between the eyes, but without the corresponding anisometropia, since the patient became aphakic after blunt trauma during childhood affecting the eye with the longest axial length, and probably as a consequence of the aphakia, she did not become amblyopic.

Evaluation of eye-related parameters and adverse events of rigid gas permeable contact lens and spectacles correction in infants with monocular aphakia after congenital cataract surgery: a retrospective clinical study

BackgroundCongenital cataract is currently one of the leading blindness-causing eye diseases in children. Surgical treatment only opens the visual pathway for children. The postoperative recovery of visual function is also dependent on effective optical correction and visual function training. In this study, we analyzed the changes in eye-related parameters, adverse events and the annual cost of rigid gas permeable contact lens (RGPCL) and spectacles correction in infants with monocular aphakia after congenital cataract surgery.MethodsTo analyze the postoperative visual acuity, strabismus, nystagmus, myopic shift, globe axial length growth, adverse events, patient adherence to patching, and annual cost for patients with unilateral congenital cataract who underwent cataract surgery. Rigid gas permeable contact lenses or spectacles were used to correct aphakia after congenital cataract.ResultsOf the 49 patients, 20 patients with unilateral aphakia who used RGPCL were in group 1. Group 2 comprised 14 patients with persistent fetal vasculature (PFV) who used RGPCL, and there were 15 patients with spectacles in group 3. In group 1, there were important improvements in visual acuity, strabismus and nystagmus. In groups 2 and 3, there were no significant improvements in visual acuity, strabismus or nystagmus. Patients with a good adherence to patching had better visual acuity after the operation than patients who did not, in groups 1 and 3. There were no significant differences in myopic shift or rate of globe axial length growth among the 3 groups. No patients in group 1 had ocular disease that affected visual acuity. The mean annual expenses of the RGPCL group was 3965 yuan, and the mean annual cost of spectacles was 1140 yuan to 2500 yuan.ConclusionRGPCL is a safe and effective optical correction method for patients with monocular aphakia after congenital cataract surgery. Spectacles are not an ideal optical correction. Using RGPCL to correct patients with PFV, the final visual acuity improved, but the difference was not statistically significant. There were no improvements in strabismus or nystagmus in patients with PFV.

Comparison of Contact Lens and Intraocular Lens Correction of Monocular Aphakia During Infancy

The Infant Aphakia Treatment Study recommended primary intraocular lens (IOL) implantation be reserved for infants with parents unable to manage contact lenses. The best baseline predictor of a good visual outcome was private health insurance. IOL implantation was associated with more adverse events, but lower direct costs to parents.

Comparison of Contact Lens and Intraocular Lens Correction of Monocular Aphakia During Infancy

The efficacy and safety of primary intraocular lens (IOL) implantation during early infancy is unknown. To compare the visual outcomes of patients optically corrected with contact lenses vs IOLs following unilateral cataract surgery during early infancy. The Infant Aphakia Treatment Study is a randomized clinical trial with 5 years of follow-up that involved 114 infants with unilateral congenital cataracts at 12 sites. A traveling examiner assessed visual acuity at age 4.5 years. Cataract surgery with or without primary IOL implantation. Contact lenses were used to correct aphakia in patients who did not receive IOLs. Treatment was determined through random assignment. HOTV optotype visual acuity at 4.5 years of age. The median logMAR visual acuity was not significantly different between the treated eyes in the 2 treatment groups (both, 0.90 [20/159]; P = .54). About 50% of treated eyes in both groups had visual acuity less than or equal to 20/200. Significantly more patients in the IOL group had at least 1 adverse event after cataract surgery (contact lens, 56%; IOL, 81%; P = .02). The most common adverse events in the IOL group were lens reproliferation into the visual axis, pupillary membranes, and corectopia. Glaucoma/glaucoma suspect occurred in 35% of treated eyes in the contact lens group vs 28% of eyes in the IOL group (P = .55). Since the initial cataract surgery, significantly more patients in the IOL group have had at least 1 additional intraocular surgery (contact lens, 21%; IOL, 72%; P < .001). There was no significant difference between the median visual acuity of operated eyes in children who underwent primary IOL implantation and those left aphakic. However, there were significantly more adverse events and additional intraoperative procedures in the IOL group. When operating on an infant younger than 7 months of age with a unilateral cataract, we recommend leaving the eye aphakic and focusing the eye with a contact lens. Primary IOL implantation should be reserved for those infants where, in the opinion of the surgeon, the cost and handling of a contact lens would be so burdensome as to result in significant periods of uncorrected aphakia. clinicaltrials.gov Identifier: NCT00212134

Iris claw intraocular lens: A viable option in monocular surgical aphakia

To evaluate the safety and efficacy of iris claw intraocular lens (IOL) implantation for correction of monocular surgical aphakia in eyes with no capsular support. This is a prospective interventional case series of 30 eyes of monocular surgical aphakia. Patients underwent posterior iris claw implantation 4 weeks after the primary surgery. Aphakia which resulted due to posterior capsular rupture, large zonulo-dialysis (>180°) and cases of intracapsular cataract extraction in subluxated cataractous lens (>180°) where a posterior chamber IOL could not be placed were included in this study. Postoperatively, best-corrected visual acuity (BCVA) improved significantly (P < 0.02), 80% of patients had good vision of (20/20 to 20/40) and endothelial cell loss was 8.96% at 6 months. Secondary iris claw intraocular lens implantation is a viable option to correct monocular aphakia in eyes without capsular support.

A Randomized Clinical Trial Comparing Contact Lens With Intraocular Lens Correction of Monocular Aphakia During Infancy

To compare the visual outcomes and adverse events of contact lens with primary intraocular lens (IOL) correction of monocular aphakia during infancy. In a randomized, multicenter (12 sites) clinical trial, 114 infants with a unilateral congenital cataract were assigned to undergo cataract surgery between 1 to 6 months of age either with or without primary IOL implantation. Contact lenses were used to correct aphakia in patients who did not receive IOLs. Grating visual acuity was tested at 1 year of age by a masked traveling examiner. Grating visual acuity at 1 year of age. The median logMAR visual acuity was not significantly different between the treated eyes in the 2 groups (contact lens group, 0.80; IOL group, 0.97; P = .19). More patients in the IOL group underwent 1 or more additional intraocular operations than patients in the contact lens group (63% vs 12%; P < .001). Most of these additional operations were performed to clear lens reproliferation and pupillary membranes from the visual axis. There was no statistically significant difference in grating visual acuity at age 1 year between the IOL and contact lens groups; however, additional intraocular operations were performed more frequently in the IOL group. Until longer-term follow-up data are available, caution should be exercised when performing IOL implantation in children aged 6 months or younger given the higher incidence of adverse events and the absence of an improved short-term visual outcome compared with contact lens use.

Persistent diplopia following secondary intraocular lens placement in patients with sensory strabismus from uncorrected monocular aphakia

Aim:To evaluate the incidence of persistent diplopia after secondary posterior chamber intraocular lens (PCIOL) implantation in patients with prolonged uncorrected monocular aphakia with associated sensory strabismus.Methods:A retrospective institutional case series...

Optical Problems and near Vision

Optical problems related to near vision are caused by one of two factors. Some are related to the fact that near vision requires different accommodative effort than distance viewing. Other problems are related to the fact that near vision usually occurs in the downgaze reading position, and there are some clinical situations for which downgaze poses unique optical problems. This report presents ten specific optical problems associated with near vision. They include: 1) increased accommodative demands in myopes switching to contact lenses; 2) problems with bifocal contact lenses with high AC/A esotropia; 3) decompensation of accommodative esotropia with approaching presybopia; 4) the need for on-going cycloplegic refractions in former accommodative esotropes; 5) problems with monovision; 6) fixation switch diplopia/asthenopia; 7) monocular aphakia; 8) induced prism in downgaze from anisometropia; 9) vertically incomitant strabismus causing problems in presbyopes; 10) disadvantages of no-line bifocals with vertically incomitant strabismus.

Morphology of M-cell axon arbors in striate cortex of monkeys reared with monocular aphakia

Although the effects of visual deprivation on the development of ocular dominance columns have been well described in primates, nothing is known in primates about the impact of the deprivation on the axonal profiles that make up the ocular dominance columns. We now show that the effects of monocular deprivation on the morphology of geniculostriate axons involve not only shifts in terminal arbor sizes, much as would be expected from the ocular dominance data, but also changes in the proliferation of terminal arbor branches. In macaque monkeys reared from birth with unilateral lens removal (aphakia), terminal arbors of geniculostriate axons were bulk-filled with horseradish peroxidase (HRP) in brain-slice preparations and reconstructed from serial sections through striate cortex (area 17). Our focus was on the arbors that terminate in the upper tier of layer IV, the target of cells in the magnocellular (M) layers of the LGN. Of the 26 M-cell arbors reconstructed from three aphakic monkeys, eight were unique in having few very simple terminal arbor branches. These also tended to be smaller in total extent than the average M-cell axons reconstructed from 1 normal monkey. In contrast, eight arbors had very rich terminal branching patterns, and seven of these were larger than any of those from the normal monkey. We propose that the small, sparse axon arbors are related to the deprived eye, and the large, dense arbors are related to the non-deprived eye. These morphological changes reflect abnormalities in the growth patterns of geniculostriate inputs that undoubtedly have important persisting consequences for visual performance.

Post-Operative Refractive Correction and Contact Lens Fitting in the Aphakic Patient

Postoperative refractive correction of the aphakic infant can be accomplished using contact lens (CL) and/or glasses. The presence of monocular or binocular aphakia, the condition, or health of the aphakic eye(s), and the home environment of the child all play key roles in determining the most appropriate means of correction. When contact lenses are used a variety of lens materials are available. These include Soft, Silicone, Rigid Gas Permeable and Hard (PMMA). The choice depends on the corneal steepness, and diameter, the refractive power of the eye, the selected wearing schedule, and the preference of the CL fitter. Glasses are important to prescribe to the aphakic child for use when the contact lenses have been removed. Bifocal correction will be necessary for both monocular and binocular aphakia, whether in aphakic spectacles, or in glasses to be worn over the aphakic contact lenses. This paper is a discussion of the advantages and disadvantages of contact lens use with aphakic children, the use of specific types of contact lens plastics for refractive correction, and the role of glasses for the aphakic child.

Monkey Model of Neonatal Monocular Pseudophakia

The safety and efficacy of correcting monocular aphakia during infancy with an intraocular lens was evaluated using a monkey model. The study was conducted at the Yerkes Regional Primate Research Center. A translucent contact lens was placed on the right eye of a group of newborn Rhesus monkeys to simulate a congenital cataract. When the monkeys were 2-weeks-old, a lensectomy was performed on the right eye coupled with the implantation of an intraocular lens (IOL) into the posterior chamber. The fellow eyes were then randomized to part-time occlusion therapy or no treatment. The monkeys were then examined at regular intervals for complications. Visual acuity and contrast sensitivity was evaluated using forced-choice preferential looking and operant testing. The pseudo-phakic eyes were studied histopathologically at the end of the study. A variety of complications occurred postoperatively including fibrin encapsulation of the intraocular lens, glaucoma, haptic breakage, and lens reproliferation into the pupillary space. Grating acuities were excellent for the pseudophakic eyes of the monkeys that received part-time occlusion therapy, but severely reduced in the pseudophakic eyes of the monkeys that received no treatment of the fellow eyes. An unexpected finding was that the pseudophakic eyes were consistently shorter than their fellow phakic eyes. The implantation of an intraocular lens into an infantile monkey eye can be associated with a variety of serious complications. Intraocular lenses custom-designed for infantile eyes may reduce the incidence of these complications. In eyes not developing these complications, excellent visual acuities can be obtained if the fellow eyes are occluded part-time.

Scleral Fixation of Posterior Chamber Intraocular Lenses in Children

Children with monocular aphakia who become contact lens intolerant require an intraocular lens (IOL) for visual rehabilitation. When there is inadequate support from the posterior lens capsule, use of an anterior chamber IOL or a sclerally fixated posterior chamber IOL may be considered. The authors report their experience with scleral fixation of posterior chamber IOLs in children. Seven posterior chamber IOLs were sutured in the ciliary sulcus of children who could not wear contact lenses. In each eye, the lens capsule remnants were inadequate to provide sufficient support for the haptics of a posterior chamber lens. Six of seven patients had improved visual acuity, with an average improvement of 4 lines. Complications related to scleral fixation included exposure of the scleral fixation suture in one eye, lens decentration in one eye, and lens tilt in one eye. Follow-up ranged from 3 to 38 months, averaging 26 months. Implantation of a posterior chamber sclerally fixated IOL offers an alternative to placement of an anterior chamber lens in children who cannot wear contact lenses and who lack capsular support. Continued follow-up of these patients will help determine the long-term safety of this technique.

Unexpected cyclotropia simulating disruption of fusion.

Fifteen patients with diplopia associated with prior scleral buckling, prior penetrating keratoplasty, severe corneal scarring, monocular aphakia, long-standing strabismus, or prior vertical offsets of the horizontal recti were thought to have disruption of fusion because diplopia could not be eliminated with prisms. They were each found to have a substantial symptomatic cyclotropia unassociated with an obvious dysfunction of an oblique muscle. In 13 patients, diplopia resolved after the cyclotropia was corrected surgically.

Stereopsis After Congenital Monocular Cataract Extraction

Congenital monocular cataract extraction was performed on a 1-day-old baby girl and a hydrophilic contact lens was fitted. A progressive regimen of part-time occlusive therapy was then instituted. Eight years later, the girl has a visual acuity of 20/25 in the operated-on eye and 50 seconds of arc of stereoacuity that has been confirmed by an independent pediatric ophthalmologist. This patient demonstrates the potential for high-grade stereopsis in congenital monocular aphakia.

Binocular vision regained after monocular traumatic aphakia by wearing contact lenses.

In this study 35 patients with monocular traumatic aphakia were enrolled to document the degree of binocular vision gained by optical correction with contact lenses. The most important factors in achieving binocular vision were the interval between formation of the traumatic cataract and surgery and between the operation and starting wearing contact lenses. There was a statistically significant correlation between these two intervals and the achievement of near stereopsis and normal visual acuity.

Effects of Aphakia on the Geniculostriate System of Infant Rhesus Monkeys

The effects on the visual system of rearing rhesus monkeys with monocular aphakia, corrected with extended-wear contact lenses, were assessed with anatomical, electrophysiological and behavioral methods. The major finding was that the effects of the various treatments on the aphakic eye varied in degree depending upon the amount of focused pattern input received by the aphakic eye compared to its fellow eye. The behavioral, electrophysiological and anatomical assessments of the treatment effects on the aphakic eyes correlated closely with each other. Because this experimental paradigm is similar to current clinical procedures for treating human infantile monocular cataracts, it provides a nonhuman primate model for studying aphakia.

Epikeratophakia--a new procedure in refractive surgery of the cornea

The epikeratophakia operation developed by Kaufman represents an additional procedure in refractive surgery of the cornea. The application of individually prepared corneal tissue lenticles on top of the recipient cornea can be used in refractive (Keratolens) and tectonic (Keratopatch) problems. The most important indication for this operation is monocular aphakia in which a contact lens is not tolerated. As is pointed out in the literature, postoperative visual acuity is reduced in some patients by interface densities and incomplete epithelialization. The advantage of this newly developed method is that it offers the ophthalmic surgeon a novel procedure for the indications mentioned which does not involve any major investment in apparatus.

Secondary lens implantation: incidence, indications and complications.

A retrospective study of 79 secondary intraocular lens implants performed during 1984-87 in a large teaching hospital is reported. The period of follow-up ranged from 6 months to 3.9 years (mean 16.6 months). The principal indication for surgery was contact lens intolerance. Thirty-four per cent of the patients had previously undergone cataract surgery with implantation of the other eye. Eighty-three per cent of the patients achieved a visual acuity within one Snellen line of best-corrected preoperative visual acuity. A further 2.5% lost two lines of Snellen chart acuity, and 14.5% had a substantial reduction in visual acuity. We conclude that in carefully selected patients secondary intraocular lens implantation is an acceptable and often highly successful way of treating monocular aphakia and we discuss the selection and preoperative investigation of such patients.