Monocular Cataract Research Articles

Congenital cataract - new indications for surgery

The visual function of 64 infants with congenital cataracts was evaluated by means of the electroretinogram (ERG) and visually evoked potential (VEP). Among ten cases with monocular congenital cataract, two showed a normal VEP and eight an abnormal VEP, suggesting form vision deprivation amblyopia. From the combined recording of the ERG and VEP in infants with binocular congenital cataract, 17% of the associated nystagmus can be attributed to abnormalities of the retina and/or optic nerve. The other 83% nystagmus seemed to be the consequence of visual deprivation due to the cataracts themselves. Visual acuity in infants with congenital cataract was examined by a preferential looking technique, and a new criterium for early surgery for congenital cataract was adopted.

Monocular and binocular congenital cataract

The visual results achieved after surgery in 38 patients with monocular congenital cataract and 34 with binocular congenital cataracts are reported. Thirty-two of the monocular aphakics were corrected postoperatively by contact lenses and six by intraocular lenses. Only one of the 32 eyes corrected with contact lenses achieved a visual acuity of 6/60 and 31 demonstrated a visual acuity lower than 6/60 (20/200). On the other hand, out of the six patients corrected by intraocular lenses, three whose visual acuity could be reliably recorded all achieved a visual acuity better than 6/60 and two of them reached a visual acuity of 6/12(20/40). From our group of patients with binocular congenital cataract it appears that delayed surgery beyond one year of age when the lens opacity allows undisturbed activity resulted in better visual acuity than in eyes whose opacity disturbed the child's activity and necessitated earlier surgery.

Visual System Screening in Infants and Young Children

Many abnormalities of the visual system in infants and young children respond to treatment when instituted at an early age. Ocular abnormalities that require early recognition and therapy include congenital cataracts, congenital glaucoma, intraocular tumors, intraocular inflammation, large errors of refraction, strabismus, and corneal opacities (Figs 1 to 6). The visual prognosis for children with these problems is often directly related to early detection and treatment of the visual disorder. Visual deprivation of young laboratory animals can permanently damage their developing central nervous system. Diseases once believed hopeless, such as monocular congenital cataracts, can now be treated.1 Technologic advances, such as extended-wear contact lenses which are useful for infants who have had cataract surgery during the first few weeks of life, have facilitated visual rehabilitation of young eyes. Corneal opacities, complete ptosis, prolonged patching, and eyelid or orbit abnormalities such as large hemangiomas can cause amblyopia if the vision is obstructed. Even brief occlusion can result in irreversible amblyopia during the early months of life.2 Unilateral disruptions of vision are generally more damaging to the eye than are bilateral ocular abnormalities. Each of the young child's eyes must enjoy a clear, focused retinal image for visual development to progress normally. Early diagnosis and treatment of congenital glaucoma is important so that intraocular pressure can be lowered, thereby, avoiding irreversible anatomic damage to the eye.

Long term visual deprivation in a human

D.C. had a congenital monocular cataract removed at 19 years of age. Preoperatively, he was virtually blind in the deprived eye. By 4 months after surgery he could resolve about 1.4c/deg but acuity did not improve further over the next 7 months. Immediately postoperatively, the temporal retina was blind, but over the next 4 months its visual field increased to 20. The temporal retina continued, however, to have elevated thresholds. D.C. also exhibited a peculiar form of binocular competition. Thresholds of the deprived binocular portions of the nasal retina were greatly elevated by light falling on the non-deprived eye. Visual function in the non-deprived eye was normal.

Good Visual Function after Neonatal Surgery for Congenital Monocular Cataracts

We treated eight neonates who had total, monocular, congenital cataracts with surgery, occlusion, and contact lenses. Visual results in all eight patients were good. In five patients visual acuities improved to 6/9 (20/30) or better in the aphakic eye. In three patients visual acuities improved to 6/24 (20/80) or better. Problems with contact lenses probably accounted for the poorer results in two of these three patients. Binocularity was not demonstrated in any of our patients.

A Singular View (The Art of Seeing With One Eye).

The sudden loss of an eye presents practical and emotional problems that are not always fully understood by two-eyed individuals. The author, an aviation safety expert who lost his right eye in a freak flying accident, resolved to help his fellow sufferers with the practical aspect of adjusting to monocular vision. The result is a readable and sympathetic book that ophthalmologists will find helpful to their patients, not only the truly oneeyed but also those with monocular cataract and monocular aphakia during the interval before their rehabilitation with a contact lens. Determined to rise above his misfortune, the author spent the two years following the accident relearning to drive a car and fly a plane. He also built a ship model and wooed and won a wife. His achievement is well summarized in the foreword by John W. McTigue: "This book will interest anyone who is curious about the workings

Re-Evaluation of Monocular Cataracts in Children

Re-Evaluation of Monocular Cataracts in Children

The retinal disease of rubella.

AN AUSTRALIAN physician, Aileen Mitchell, was the first to note fundus changes in a child born with rubella. 1 In his initial report before the Ophthalmological Society of Australia in 1941, Gregg did not mention this observation. 2 Several years later, however, while reviewing his notes of case reports collected for this original paper, 1 he cites the following fundus description by Dr. Mitchell from a child with a left-sided monocular cataract: fundus of the right eye appeared pale, and some scattered irregular spots of pigment were observed. Rubella retinitis is now recognized as one of the three most frequent ocular abnormalities in a child with congenital rubella. The exact incidence is uncertain since eyegrounds are sometimes not visualized because of dense congenital cataracts. Reported frequencies are: 16 out of 120 cases, 3 17 out of 38 cases, 4 15 out of 29 cases, 5 50 out of 82

Contusive angle recession in phacolytic glaucoma.

Phacolytic glaucoma is a distinct entity than can be recognized clinically and pathologically. It is manifested clinically by the acute onset of glaucoma in an eye with a hypermature cataract. Cells and flare are present in a deep anterior chamber, and typically there is a lack of synechias as well as a lack of keratic precipitates. Appropriate treatment consists of prompt cataract extraction with irrigation of the anterior chamber. One of the clinical features of phacolytic glaucoma that has been emphasized is its occurrence in elderly patients with senile cataracts who present no evidence of any other intraocular disease. In the clinicopathologic study of Flocks et al, 1 the majority of the 138 patients were over 70 years of age, and the fellow eye was aphakic. In only eight cases were the cataracts considered of traumatic origin. These eight cases were included in a group of patients with monocular cataract

Monocular Aphakia and Intraocular Lenses

There has always been a difference of opinion concerning the handling of uncomplicated monocular cataracts whether they be congenital, traumatic, or senile. No one questions the necessity for removal of such cataracts when they are swollen and likely to produce glaucoma or when secondary iritis develops, or in those rare instances when a patient's livelihood requires binocularity or the removal of a cosmetic blemish. On the other hand, removal of monocular congenital cataracts is rarely indicated, since such eyes frequently harbor other malformations and are usually incapable of generating useful vision. One does not have to be in practice very long to realize that removal of a monocular cataract in most individuals is not a procedure to evoke unqualified gratitude from the patient. In spite of painstaking preoperative discussion, pointing out the difficulties of binocular vision, and, if such is desired, the need for contact and possibly aniseikonic lenses, the

Acrylic lenses in the anterior chamber; experimental studies in animal eyes.

The correction of certain refractive errors, either intrinsic or resulting from removal of the lens, by insertion of a plastic lenticulus within the eye has been attempted by several ophthalmic surgeons. The first to report the use of intraocular acrylic lenses after monocular cataract extractions was Ridley, 1 in 1952. His purpose was to overcome the disadvantages of correcting the aphakic eye by spectacles, which include magnification of the image, distortion and displacement of images outside the optic center, and marked limitation of the fields of vision. He obtained binocular vision by inserting an intraocular lens behind the iris (Fig. 1 A ). The lens he used was made of polymethyl methacrylate, fashioned slightly smaller than the human lens. It was 8.35 mm. in diameter and 2.4 mm. in thickness; the radius of curvature of the anterior surface was approximately 9 mm., and that of the posterior surface was 5.3 mm.

The management of monocular cataracts.

For the purpose of this discussion a monocular cataract will be defined as advanced opacification of the crystalline lens in one eye, while the other lens is clear or has opacities that have not yet affected visual acuity. The case of the infant born with monocular cataract is another problem and will not be discussed here. Until recently a cataract in one eye was allowed to go to maturity and beyond as long as the vision remained useful in the other eye. An ancient dictum said one should wait until vision dropped to 20/70 in the better eye before operating on the other. The reasoning behind this was that as long as the patient could see well enough to get around and to do close work with the better eye, the eye operated on would be of little or no good. A patient could not wear a cataract lens before

CONTACT LENSES IN APHAKIA

THE PROBLEMS of aphakic vision have plagued the cataract patient and the ophthalmologist for a long time. Much has been written on the subject which need not be reviewed here. In 19341Cowan discussed the problem, and Kirby2has summarized it well in his text. The subjective sensations were strongly emphasized in a recent dramatic anonymous editorial.3 In addition to the ordinary problems of aphakic vision, those posed by the patient with unilateral aphakia and an essentially normal fellow eye seem so great that many ophthalmologists have opposed operation on monocular cataracts. The recent successful introduction of intraocular acrylic prostheses*has rekindled interest in this entire question. Optically, the new technique would appear to be the most nearly ideal arrangement, particularly for the patient with monocular aphakia. It is not our province to assess the practical risks of such an operation, nor can we, or any one,

RESTORATION OF BINOCULAR VISION AFTER UNILATERAL CATARACT EXTRACTION

It is usually considered that full correction cannot be worn after cataract extraction if the eye not operated on has normal vision. Most ophthalmologists (including myself) have made it a practice not to encourage patients with monocular cataract to have extraction done. This advice has been given because it has been felt that a correction could not be worn and the only advantage of the operation to the patient would be the cosmetic improvement and the increased field of vision. Ophthalmologists have neglected to have their patients make a fair trial with full correction to see whether it would be tolerated, because it has been felt that there was such a remote possibility of success. This paper is written to create interest among ophthalmologists in carrying out a thorough trial with full correction. Little information of a specific nature is found in textbooks or in the literature on this subject.

CONTACT GLASSES FOR CORRECTION OF REFRACTIVE ERRORS IN MONOCULAR APHAKIA

The problem of refraction in cases of monocular aphakia is as old as ophthalmology itself. The difficulty in prescribing lenses for both eyes is frequently encountered, and the explanation given as to why the two eyes cannot function harmoniously is usually hard for the patient to accept. Heretofore when a patient presented himself with a monocular cataract it was necessary to decide whether to operate or not. The decrease in the visual field and the annoyance of an economically blind eye were points in favor of operation. However, the disappointment to the patient when the refractive errors of the two eyes could not be harmoniously corrected was usually the deciding factor against operation. Only since the use of contact glasses has this factor been overcome. HISTORY OF CONTACT GLASSES Contact glasses were first used by Herschel in 1827, although the first experiments in the departure from the ordinary optical lens

Two Cases of Monocular Cataract; with remarks

Two Cases of Monocular Cataract; with remarks