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At least 19 recordsLinked to original sources
PubMed2004

Postoperative aphakia in modern cataract surgery: part 2: detailed analysis of the cause of aphakia and the visual outcome.

PURPOSE: To study the incidence of aphakia after cataract surgery, the surgical complications that can lead to it, and the visual outcome. SETTING: Six community-run eye clinics participating in the Swedish National Cataract Register. METHODS: Data on cataract extractions were collected prospectively from 1997 through 2001. The data also covered the type of surgery and type of intraocular lens, including a "no lens implanted" option. All data were stored in a database. These data were supplemented with data on the intended type of surgery, type of complications, possible second surgery, and visual outcome. RESULTS: The overall incidence of postoperative aphakia was 0.65%. In 87.1% of cases, the aphakia was not planned, corresponding to an incidence of 0.48%. Unplanned aphakia was significantly related to poor preoperative vision, old age, and the presence of ocular comorbidity. The most frequent reasons for unplanned aphakia were intraoperative capsule problems and vitreous loss. In two thirds of cases, a second operation was performed. In 41% of all cases, the final visual acuity was 0.5 or better and in 27.7%, worse than 0.1. CONCLUSIONS: During the study period, 1 of every 200 routine cataract surgeries ended in unplanned aphakia. The incidence of surgical complications leading to unplanned aphakia and a final visual acuity worse than 0.1 (20/200) was 7.8 per 10,000 operations in cases with no ocular comorbidity and 27.6 per 10,000 operations in cases with ocular comorbidity.

Aged↗
PubMed2004

Postoperative aphakia in modern cataract surgery: part 1: analysis of incidence and risks based on 5-year data from the Swedish National Cataract Register.

PURPOSE: To study the incidence of aphakia after cataract extraction and evaluate the relative risk for this outcome in subgroups of patients based on preoperative conditions. SETTING: Sixty-two community-run or private clinics participating in the Swedish National Cataract Register. METHODS: Data on cataract extractions were collected prospectively from 1997 through 2001. The set of data also covered type of surgery and type of intraocular lens (IOL), including a "no lens implanted" option. All data were stored in a database. Database calculations were made of frequencies and risk ratios of postoperative aphakia in the subgroups of patients based on preoperative conditions. RESULTS: For the entire study period, postoperative aphakia was reported in 1410 of 287,951 surgeries for which complete IOL data were available, corresponding to an overall frequency of 0.49%. The occurrence of ocular comorbidity and poor preoperative visual acuity (< or = 0.1) in the eye to be operated on was significantly related to postoperative aphakia for each year of the study (P<.001). Glaucoma and poor visual acuity (< or =0.1) in the surgical eye meant a 12.8 higher risk for aphakia after surgery than a better visual acuity (>0.1) and no ocular comorbidity. CONCLUSIONS: This national 5-year survey showed that in routine cataract surgery performed during the study, 1 of every 200 operations ended in postoperative aphakia. Poor visual acuity (< or =0.1) in the eye to be operated on combined with ocular comorbidity was the highest risk factor for postoperative aphakia.

Aged↗
PubMed1989

Epikeratoplasty for adult and pediatric aphakia, myopia, and keratoconus: the Massachusetts Eye and Ear Infirmary experience.

Between February, 1985 and February, 1987, 49 eyes of 47 patients underwent epikeratoplasty for one of the following indications: adult aphakia (21 eyes; 20 patients), pediatric aphakia (10 eyes; 10 patients), myopia (7 eyes; 6 patients), and keratoconus (11 eyes; 11 patients). Follow-up at least 12 months (average = 18 months) is available for all 49 eyes. Of 49 eyes, 44 (90%) were anatomically successful with an intact, clear lenticule at least 12 months post-operatively, with no significant difference between the four groups (adult aphakia = 90%, pediatric aphakia = 90%, myopia = 86%, and keratoconus = 91%). The functional success rate, however, was 91% for keratoconus, 81% for adult aphakia, 80% for pediatric aphakia, and only 43% for myopia. We conclude that epikeratoplasty can be an effective tool in the treatment of carefully selected patients with adult or pediatric aphakia and keratoconus, but has only limited applicability in the management of myopia.

Adult↗
PubMedDate not supplied

Congenital aphakia: a clinicopathologic report of three cases.

BACKGROUND: Congenital aphakia is a rare condition that has been classified as primary when no lens induction of the surface ectoderm occurs and secondary when lens development takes place but later is resorbed or expelled in utero. METHODS: The authors report the clinical and pathologic findings in three infants with congenital aphakia whose eyes were enucleated either at surgery at 11 months or at autopsy after 1 and 3 days of life. RESULTS: Two cases classified as primary congenital aphakia had severe microphthalmos, anterior segment aplasia, or anomalous development and posterior choroidal and optic disc colobomas. One was in a case believed to be Waardenburg's recessive anophthalmia syndrome and the other had 18 trisomy. A case of secondary congenital aphakia had findings of Peter's syndrome and features suggesting rubella, which had been observed in some previous reports. CONCLUSIONS: Primary congenital aphakia can result from a variety of teratogenic events in the first 4 weeks of embryogenesis and results in microphthalmos and severe anterior segment aplasia/dysplasia. Secondary congenital aphakia is associated with less severe ocular anomalies. The possible role of deletion or mutation involving the PAX6 gene in anterior segment anomalies and induction of lens development is discussed. In addition to chromosomal influences, in utero viral infection, particularly rubella, may play a role in some cases.

Abnormalities, Multiple↗
PubMedDate not supplied

[Evaluation of various methods effectiveness for aphakia correction in patients with myopic refraction and glaucoma].

The efficiency of various methods for correcting postoperative aphakia was evaluated in 113 patients (118 eyes) with medium and high myopia and glaucoma. In group 1 (44 eyes) extraocular correction of aphakia was planned after cataract extraction, in group 2 (33 eyes) intraocular lenses were implanted, in group 3 (21 eyes) combined interventions were performed (cataract extraction with antiglaucoma component), and in group 4 (20 eyes) cataract extraction was performed simultaneously with sinusotrabeculectomy and intraocular correction of aphakia. The number of patients with visual acuity higher than 0.1 was significantly more in groups 2 and 4 after implantation of intraocular lenses than in groups 1 and 3, who needed extraocular correction of aphakia: 59.1% in group 1, 42.9% in group 3, 78.8% in group 2, and 60% in group 4. Intraocular correction of aphakia in patients with glaucoma and myopia helps attain the maximum possible visual acuity even in patients with far-advanced stages of the disease with residual visual field. Individual approach to estimation of optic force of implanted intraocular lens helps reduce the myopic refraction of the operated eye.

Adult↗
PubMed1993

Aphakia and artificial lens implants in the civil airman population.

The Federal Aviation Administration allows civilian airmen with aphakia to fly with waivered certificates. This study analyzes, in the civil airman population, the distribution of aphakia and intraocular lens (I.O.L.) implant by type (unilateral, bilateral), class of airman medical certificate, and gender, for a 4-year period (1982-85). Medical records were individually evaluated for all certified airmen who were carrying FAA-specific codes for the pathology categories during the study period. The prevalence of both aphakia and I.O.L. increased most for bilateral type and second-class certificate holders. During the study period, the prevalence of aphakia increased most for males and I.O.L. increased most for females. The incidence declined in both pathology categories during the later years of the study period. Implications for aeromedical certification of the increasing prevalence of aphakia and I.O.L. in the civil airman population are discussed. The modification of surgical procedures for cataract extraction and evolution of I.O.L. devices strongly suggests continued specialized aeromedical certification and clinical research review.

Aerospace Medicine↗
PubMed1980

The correction of aphakia. XXXVI Edward Jackson Memorial Lecture.

Major advances in the correction of aphakia have been made in the past few years. Extended-wear contact lenses constitute one advance, if not a perfect one. Intraocular lenses are now safer to use, and new research is seeking ways to improve their safety through protection of the corneal endothelium during surgery and stimulation of endothelial healing where damage does occur. Altering the refractive power of the cornea offers another possible approach to the correction of aphakia. Modifications of Barraquer's keratomileusis procedure using preserved, preground corneas may have definite indications for certain types of aphakia, such as monocular aphakia in children and in individuals who would otherwise require secondary implants. We have experimented with a "living contact lens" of shaped donor tissue attached to the de-epithelialized surface of the eye. Such a lens of preground, preserved cornea tissue can be sutured to the patient's cornea with its central Bowman's membrane intact. A peripheral trephine mark is made, but the central cornea is untouched and the attachment of the living lens is simple. The procedure is apparently safe, and should be usable by any competent ophthalmic surgeon if the long-term results continue to be as encouraging as our early experience now suggests.

Adolescent↗
PubMed2001

A comparison of grating visual acuity, strabismus, and reoperation outcomes among children with aphakia and pseudophakia after unilateral cataract surgery during the first six months of life.

PURPOSE: The method of correcting aphakia after unilateral cataract extraction during infancy is controversial. Some authorities advocate correction with an intraocular lens (IOL) whereas others advocate correction with a contact lens (CL). We compared grating visual acuity, alignment, and reoperative outcomes in age-matched children treated with these 2 modalities at 5 clinical centers. METHODS: Twenty-five infants born in 1997 or 1998 with a dense unilateral congenital cataract who had cataract surgery coupled with (IOL group, n = 12) or without (CL group, n = 13) primary IOL implantation were enrolled in this study. All patients were prescribed half-time occlusion therapy. In July 1999, their grating visual acuities, ocular alignments, and reoperation rates were assessed. RESULTS: The mean grating visual acuity (LogMAR) for the affected eye was 0.70 +/- 0.32 for the IOL group and 0.87 +/- 0.31 for the CL group (P =.19). The mean interocular difference in grating visual acuity was 0.26 +/- 0.30 for the IOL group and 0.50 +/- 0.28 for the CL group (P =.048). The incidence of strabismus (>10 PD) was 75% in the IOL group compared with 92% in the CL group (P =.24). The incidence of reoperations was 83% in the IOL group compared with 23% in the CL group (P =.003). CONCLUSIONS: Our preliminary data suggest that correcting aphakia after unilateral congenital cataract surgery with primary IOL implantation results in an improved visual outcome but a higher rate of complications requiring reoperation. A randomized clinical trial, the Infant Aphakia Treatment Study, is planned to further study the optimal treatment for aphakia following unilateral cataract extraction during infancy.

Aphakia, Postcataract↗
PubMed2005

Striatal neuroadaptation and rescue of locomotor deficit by L-dopa in aphakia mice, a model of Parkinson's disease.

Preferential neurodegeneration of dopaminergic neurons in the ventral substantia nigra of the midbrain is a hallmark of Parkinson's disease. The homeobox transcription factor Pitx3 is similarly and selectively expressed in the same neurons. Pitx3 deficiency in a natural mouse mutant, the aphakia mouse, was correlated with the loss of these neurons and with a deficit in locomotor activity. We now report that the locomotor deficit of aphakia mice is established by 40 days of age and that it can be rescued by injection of l-dopa. We further show that downstream striatal correlates of the midbrain neuronal losses in aphakia mice, as assessed by dopamine transporter binding and expression of dopamine receptors, enkephalin, dynorphin and neurotensin, are highly similar to neuroadaptive responses observed following rapid neurodegeneration induced by neurotoxin administration in adult animals or following the progressive neurodegenerative processes as seen in Parkinson patients. Taken collectively, these data support the idea that the aphakia mice represent a selective model of dopaminergic deficiency that closely resembles the midbrain and striatal neuropathology associated with Parkinson's disease, and this suggests that these mice are a good model to assess therapies for Parkinson's disease as well as to understand the susceptibility of these neurons to neurodegeneration.

Adaptation, Physiological↗
PubMed1986

Abnormal accumulation of sulphated materials in lens tissue of mice with the aphakia mutation.

Sulphated materials were tested for in the eyes of late gestational and postnatal normal mice and mice with the aphakia mutation using Spicer's high iron diamine staining method. Qualitative identification of these materials was attempted with bovine testicular hyaluronidase and nitrous acid digestion methods. The grossly abnormal morphology of the aphakia lens made it necessary to confirm identification of lens-derived tissue by testing for lens crystallins using standard immunohistological methods. As seen in normal mouse lens maturation, accumulated inter- and intracellular sulphated materials were observed in aphakia lens tissue from just before birth through juvenile maturation. Large cyst-like structures consisting of lens-derived tissue were commonly seen in the eyes of young postnatal mutant mice. Sulphated materials formed basal lamina-like structures on many of these lens-derived units, but a well-defined lens capsule never formed. Abnormal fibrillar structures rich in sulphated materials were seen in the intraocular cavity in many older mutant specimens, most of which were largely resistant to both digestion methods. These results indicate that the potential to elaborate sulphated materials qualitatively similar to those seen in normal mouse lens maturation is present in the aphakia mutant, although the mode of accumulation is grossly disturbed.

Animals↗
PubMed1976

[Intra-ocular optics and contact lens correction in unilateral aphakia].

After an explanation of intra-ocular optics, the first results of combined contact lens correction in 42 patients are reported. As opposed to the conventional type of contact lens treatment in monolateral aphakia, this method has four main advantages: 1. It enables practically identical sight in both eyes, thus providing the necessary conditions for binocular vision both at a distance and close-up. 2. The recovery of sensomotor haptics in both eyes prevents squinting, even in the case of incipient cataract of the other eye. 3. Premature lens extraction in the second eye can be postponed and delay in lens extraction in the first affected eye can be avoided. 4. In cases where dioptric aniseikonia is very marked, as in myopia, a bilateral spectacle-contact lens combination enables tolerable binocular vision to be achieved even without an aniseikonic lens. Our findings indicate that the conventional contact-lens correction of monolateral aphakia is never satisfactory in cases with a moderate to high degree of myopia and in all refraction defects in young patients. Echometry, objective measurement of aniseikonia and combined contact lens correction helps most of these patients to regain binocular vision, both close-up and at a distance. In practice, rules of thumb and principles can be established. Even without the aid of echometry and objective aniseikonic measurement, Rule 1 enables us to prescribe combined contact lens correction for 80% of all presbyopic patients, thus enabling them to regain comfortable binocular vision. We all know that monolateral aphakia is, unfortunately, no triumph of ophthalmological science, but rather a serious eye defect that we must correct as best we can. Conventional contact lens correction, delay in operation for cataract of the first affected eye, as well as premature operation of the second eye are, in many cases, of as little help to our patients as monolateral cataract spectacles, with occlusion of the healthy eye with normal or dark glass. In contrast, combined contact lens correction in many cases of monolateral aphakia enables the patient to regain binocular vision.

Adolescent↗
PubMed1979

[The judgement of the degree of disability in cases of aphakia and pseudoaphakia (author's transl)].

Since more than 40 years the judgement of the degree of disability in cases of unilateral aphakia is discussed. This means the effort toward an advisory objectivity on the one hand and human understanding for the patient's damage on the other hand. It is supposed to repeal the 4th emergency ordinance of 1932 and to pay pensions below 20% of the degree of disability, too. As long as new legislatory measurements do not exist, the maintenance of a pragmatic authoritative activity is plead for, which assigns for a pension-duty compensation in cases of unilateral aphakia and/or pseudoaphakia independent on the optic result.--The situation in cases of bilateral aphakia is also discussed.

Aphakia↗
PubMed1983

Surgical management of chronic glaucoma in aphakia.

The surgical management of glaucoma in aphakia has been limited by poor success in the control of intraocular pressure and serious postoperative complications that threaten vision. A consecutive series of trabeculectomy filtering procedures in aphakic eyes with a mean preoperative intraocular pressure of 38 mmHg was followed for an average of 26 months and revealed a 62% control of intraocular pressure at 21 mmHg or less. Five additional patients (24%) had pressures lower than 21 mmHg following digital massage. The complication of decreased visual acuity following surgery was significant but not directly related to the surgical procedure. Another patient population with glaucoma and aphakia with a mean preoperative pressure of 25 mmHg was treated with laser trabeculoplasty. In 12 of 15 patients (80%) intraocular pressure was lower than 22 mmHg for an average of eight months and did not require glaucoma surgery. There were no significant complications following this therapy and all patients retained preoperative level of visual acuity. In aphakic patients who have uncontrolled glaucoma on maximal medical therapy, surgery is indicated. We recommend the following approach to surgical management: (1) Laser treatment to the trabecular meshwork if the angle is open; (2) if this fails, or the angle is extensively closed, a trabeculectomy filtering procedure is suggested; (3) cyclocryotherapy has been effective in controlling pressure but the unpredictable loss of vision has prompted caution in seeing eyes; (4) cyclodialysis; and (5) transpupillary or transscleral treatment of the ciliary processes are additional modes of therapy. Improved results of surgical treatment for glaucoma and aphakia have been encouraging and should be used when maximal medical therapy is ineffective.

Adult↗