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At least 19 recordsLinked to original sources
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↗
PubMed1979

Hard contact lens corrections in aphakia.

Hard contact lens correction of aphakia is best performed with a single cut lens by a trial lens fitting. Lenticular design may be necessary. Continuous wear over age 70 may be necessary to achieve success and acceptance in more than 30% of aphakic wearers. Soft lenses are usually not practical in the author's experience. The increased use of intraocular lenses is decreasing the need for aphakic contact lenses. Merits of the hard contact lens in aphakia are discussed as a practical approach to the correction of vision by the ophthalmologist, and indications for single cut lenses and lenticular design are outlined.

Age Factors↗
PubMed1992

Results of intraocular lens implantation in paediatric aphakia.

Intraocular lenses were implanted in 16 eyes of 13 patients with congenital cataract, and visual progress was plotted using a preferential-looking technique. Initial surgery was by lens aspiration with preservation of the posterior capsule, and subsequent posterior capsulotomy without anterior vitrectomy. Poly-HEMA posterior chamber lenses were used, usually as a primary procedure but in four cases as a secondary procedure after contact lens failure. No serious complications were encountered. Most eyes achieved a very significant visual improvement, and none were worse than preoperatively. Residual refractive error was highly unpredictable, but did not exceed 6 dioptres. The importance of rigorous occlusion therapy is stressed. With close follow-up, this procedure offers an effective and safe method for the correction of unilateral paediatric aphakia, and, in selected cases only, for bilateral aphakia.

Cataract↗
PubMed1979

[Fusion and aniseikonic problems in unilateral aphakia (author's transl)].

In 67 unilateral aphakic patients corrected with three different optic systems (conventional contact lens, spheric overcorrection and intraocular lens) aniseikonia and binocular vision are tested. Conventional contact lens leads to 7% aniseikonia and to fusion in only half of the cases. Patients with the two other systems show less than 3% aniseikonia and fusion in most cases. With each system only 10% of the patients reach normal stereoscopic vision. The poor results in unilateral aphakia corrected by conventional contact lens are pointed out.

Adult↗
PubMed1979

Contrast (modulation) sensitivity functions measured in patients with high refractive error with emphasis on aphakia: I. Theoretical considerations.

Recently, alterations in contrast (modulation) sensitivity functions of patients with high refractive errors have been noted. For example, this seems to be a common finding in aphakia. In some measure the observed alterations are due to the effect of the corrective lens and the optics of the eyes. These optical effects (in addition to blur) must be factored out in order to determine whether residual effects on the visual system remain. The argument is applicable to photographs of sine wave fringes as well as devices designed to produce interference patterns directly on the retina. A simple means for largely correcting these lens effects is discussed.

Aphakia↗
PubMed1979

Contrast (modulation) sensitivity functions measured in patients with high refractive error with emphasis on aphakia: II. Determinations of patients.

Measurements of Constrast Sensitivity Functions (CSF) were made on normal observers made artificially highly ametropic with spectacle lenses (with high back vertex) distance in order to determine the effect of retinal image size alterations upon CSF measures. While not an exact model for high ametropia per se, this experiment served to familiarize the experimenters with problems associated with the task. Image size alterations occur normally in aphakic patients and highly myopic patients. As a clinical trial, a series of aphakic observers were tested using an interferometric acuity device. CSF measures were made with the patient's spectacle corrections in place and again with correcting contact lenses substituted. The contact lenses reduce induced image size alterations in these cases. The use of contact lenses in such measures allows differentiation between artifactual low frequency fall off in aphakia due to lens effects and possible low frequency fall-off due to other causes.

Adult↗
PubMed1977

[Unilateral aphakia in juveniles. Results of combined correction (author's transl)].

Eighty-one unilateral aphakies under 45 years of age, 63 of which had suffered an injury, were analyzed by echometry and intraocular optics. With the aid of a computer, the majority of cases were treated for restoration of nearly equal images in both eyes by combined correction, i.e., an appropriate spectacle -- contact lens combination with both distant and near vision in the aphakie eye taken into consideration. Results with unilateral post-traumatic aphakia (63 cases) : 31 patients with uncorrected vision and 42 with a conventional contact lens suffered from symptoms of binocular confusion as opposed to only one patient with combined correction. Of the 63 patients with uncorrected vision or with a conventional contact lens, 44 had strabismus. After optimal treatment with combined correction, with or without subsegment strabismus surgery, 19 out of 23 patients were cured of their strabismus and regained a useful and comfortable, distant and near binocular vision. Thus, for juvenile unilateral aphakics, a rather good prognosis was achieved by combined correction.

Adolescent↗
PubMedDate not supplied

Elimination of aniseikonia in monocular aphakia with a contact lens-spectacle combination.

Correction of monocular aphakia with contact lenses generally results in aniseikonia in the range of 7--9%; with correction by intraocular lenses, aniseikonia is approximately 2%. We present a new method of correcting aniseikonia in monocular aphakics using a contact lens-spectacle combination. A formula is derived wherein the contact lens is deliberately overcorrected; this overcorrection is then neutralized by the appropriate spectacle lens, to be worn over the contact lens. Calculated results with this system over a wide range of possible situations consistently results in an aniseikonia of 0.1%.

Aniseikonia↗
PubMed1979

Soft lens design in aphakia.

Because of their size and mass, weight is a major concern in the fitting of soft gel lenses. Lenticular design is necessary, and there are essentially two lens designs for aphakia: the spin-cast lens of Bausch & Lomb and the lathe-cut lenses of the other manufacturers. A solution to the problem of weight in a single cut soft contact lens is presented.

Aphakia↗
PubMed1978

[Peripheral retinal lesions in aphakia].

The peripheral retina of 150 aphakic eyes with uncomplicated extraction was studied with the Goldmann three-mirror contact lens. The patients were examined 1 month to more than 2 years after cataract extraction. In addition to degenerations which are descirbed everywhere and are seen both in phakic and aphakic eyes, the authoris have emphasized lesions which they consider to be specific of aphakia. These lesions are retinal haemorrhages of wich four types are described; pigmentary anomalies and retinal tears and holes. Taking into consideration the great frequency of aphakic retinal detachment in comparison with phakic detachment, it is evident that such lesions must be held liable in aphakic retinal detachment.

Adult↗
PubMed1978

[The vitreous in aphakia].

The authors have studied the vitreous in 150 aphakic eyes after uneventful operations. They were examined by the slit-lamp and the Goldmann three-mirror glass. Two types of lesions were revealed: (1) 42% showed rupture of the anterior hyaloid membrane; this is not considered dangerous. (2) 69.3% showed posterior detachment of the vitreous, a more serious lesion. It is often associated with retinal lesions such as haemorrhage, pigmentary anomalies, and retinal tears. In view of such lesions, one cannot consider the aphakic patient as a normal subject and aphakia as a physiological condition. The frequency of retinal detachment in the aphakic bears witness to it.

Adult↗
PubMed1977

Contact lens in aphakia.

Aphakia may be said to be the best reason for contact lenses. All types are used--(hard) corneal lenses, soft lenses both for daily and extended wear, and even (hard) scleral lenses in exce,tional cases. At present all have their problems so that, although on theoretical grounds an extended wear lens would be ideal, the corneal lens is probably still the lens of choice.

Aphakia, Postcataract↗
PubMed1977

The theoretical ideal for an artificial lens implant to correct aphakia.

In considering the theoretical ideal for an artificial intraocular lens implant to be used in the correction of aphakia it has always been taken for granted that Nature's bioconvex lens is best. But there is some evidence that other configurations may be an improvement. We also have to decide how large it should be and whether it should be placed in front of the iris or behind it. Moreover we have to consider the management of eyes which are already aphakic when first seen and cataractous eyes requiring lens extraction before the pseudophakos can be inserted.

Aphakia↗
PubMed1978

[On the correction of posttraumatic unilateral aphakia in children and in adults with artificial intraocular lens implants (author's transl)].

The problems of optical correction of unilateral traumatic aphakia are discussed. The treatment of choice is a combined Cataract-operation with intraocular lens implants. The operation must be done as soon as the eye is free of inflammation. Prescription of bifocal glasses in addition to pseudophakoi is necessary. With this method a "malignant" Strabismus can be avoided and binocular vision, stereopsis as well as minimal grade of aniseikonia can be achieved.

Adolescent↗
PubMed1979

An extended wear hard contact lens in aphakia.

In reviewing the literature, there are several reports of limited success with both hard and soft contact lenses for continuous or extended wear. Aphakia is the most common indication for continuous wear, especially in monocular aphakes who are unable to insert and remove their lenses for various reasons. Because of its unusual oxygen permeability, silicone is the logical choice of material for an extended wear lens. However, because of the problems in manufacture, as well as its hydrophobic characteristics, poor centering, and problems with proper edging, no silicone lens has had wide clinical application to date. This paper reports on a preliminary study in a group of 21 aphakic patients fitted with the Polycon lens made of a new material consisting of polymethylmethacrylate in combination with silicone. Although gas permeable, the oxygen permeability is probably not adequate to maintain corneal metabolism without some interchange of oxygen containing tears. However, a significant proportion of the patients were able to wear this lens for an extended period of time without removal.

Aged↗
PubMed1979

Extended wear of hydrophilic contact lenses in aphakia - an alternative to intraocular lens implantation.

Since not every patient will be a candidate for an intraocular lens, there will always be a portion of aphakic patients who are candidates for extended wear hydrophilic lenses. Aphakic patients to be fitted successfully with extended wear contacts must be motivated, aware of the risks, and require frequent lens cleaning and replacement on an individual basis. While future improvement of hydrophilic lenses is to be expected and anticipated, the extent of these improvements is still uncertain. However, preliminary reports are encouraging. Extended wear contact lenses are not the only answer to aphakia. They are but one alternative available to the ophthalmologist for maximizing the visual rehabilitation of the aphakic patient. Even with the increasing use and acceptance of intraocular lenses, the use of extended soft lens wear has a place in this rehabilitation.

Aphakia, Postcataract↗