Blindness in mentally retarded children

A preliminary survey of the causes of blindness in mentally retarded children in Denmark showed that 50% of the children had optic atrophy, 12.5% had cataract while tapeto-retinal degenerations, other malformations and retrolental fibroplasia each represents 8–9% of the causes of blindness. The survey, was done through written notification and some patients with tapeto-retinal degenerations might have been wrongly diagnosed.     

Blindness in mentally retarded children

A preliminary survey of the causes of blindness in mentally retarded children in Denmark showed that 50% of the children had optic atrophy, 12.5% had cataract while tapeto-retinal degenerations, other malformation and retrolental fibroplasia each represents 8-9% of the causes of blindness. The survey, was done through written notification and some patients with tapeto-retinal degenerations might have been wrongly diagnosed.     

Retinal detachment in pseudophakia

In a group of 2,281 eyes after extraction of a cataract and implantation of an iris clip lens (1,362 eyes after intracapsular extraction and 927 eyes after extracapsular extraction) motion of the retina occurred in 36 eyes (1.67%), incl. 27 after intracapsular extractions (1.98%) and 9 after extracapsular extractions (0.97%). In patients with pseudophakic retinal detachment after implantation of an iris clip lens the frequency of factors which might interfere with the development of this complication was investigated. The latter proved to be the following: prolapse of the vitreous body, luxation of the implanted lens, posterior uveitis and myopia. Detachment of the retina was preceded by: peroperative prolapse of the vitreous body in 34.21%, luxation of the implanted lens in 28.95%, posterior uveitis in 36.85% and myopia (up to -4.0 Ds) in 21.05%. Anatomical and functional results after operation of pseudophakic motion were evaluated in 38 eyes (36 eyes operated on account of cataract in the authors' department, two in other departments). The minimal follow up period after operation of retinal detachment was six months. Anatomical restoration of the retina was achieved in 23 eyes (60.53%), in 9 eyes a residual motion remained (23.68%) and in four eyes total motion (10.53%). In two eyes keratopathy developed (5.26%). Central vision 6/6-6/12 was achieved in 18.42%, 6/15-6/36 in 21.05%, 6/60-3/60 in 28.95% and less than 3/60 in 31.58%. In the poorer anatomical and functional results after operation of pseudophakic motions participate in addition to the above mentioned ones difficult visualization of the retinal periphery and the extent of surgical trauma during surgery of detached retinas.     

Retinal detachment in aphakia

In a prospective study five hundred consecutive cases of cataract operations were followed during ten years. Nine cases of retinal detachment were observed. In a retrospective study 77 cases with aphakic retinal detachment were studied according to type of cataract operation, interval between this operation and the onset of retinal detachment, refraction, area of detachment and results of treatment. About fifty percent of the cases of retinal detachment are observed during the first year after the cataract operation. At the first examination the detached area is usually larger in aphakic eyes than in phakic eyes. The anatomical and functional cure after detachment operation is probably less in aphakic than phakic eyes.     

Retinal detachment in pseudophakia

Retinal detachment in an aphakic eye is a grave therapeutical problem. There exists some fears that cataract extraction with implantation of an artificial lens may increase the number of these complications. Three hundred and seventy cases of cataract extraction with implantation of an artificial lens performed in our department were analysed from the point of view of the incidence of retinal detachment. The cataract was extracted extra- and intracapsularly and the artificial lens was implanted in the anterior as well as in the posterior chamber. During the period of observation--4 months to 3 years--it was established that the number of the retinal detachment in pseudophakia was not larger than in aphakic eyes without implant.