Cataracts in Children.
The treatment of a cataract in a young child depends on the cause of the cataract, whether it is unilateral or bilateral, the presence of other ocular or systemic disease, the degree to which it interferes with vision, and the ability of the patient to adjust to optical correction.
Visual results in aphakic children.
Children with small cataracts in the main axis of vision may obtain good vision by seeing around the opacity if the pupils are kept dilated (Fig. 2
). These cataracts frequently do not progress.
If the cataracts are bilateral and severe, removal of the lens is necessary for development of the normal visual fixation reflex. The current concepts of functional amblyopia necessitate a clear visual axis during the important formative years of the visual apparatus.
- Von Noorden GK
- Crawford MLJ
The sensitive period.
Ocular nystagmus occurs if the cataracts prevent the development of the fixation reflex during the first 3 months of life, and this condition further handicaps the processing of visual information.
- Rogers GL
- Tishler CL
- Tsou BH
- Hertle RW
- Fellows RR
Visual acuities in infants with congenital cataracts operated on prior to 6 months of age.
Once nystagmus develops, it persists even if the cataracts are subsequently removed, and affected patients rarely have vision better than 20/200 (6/60), which constitutes legal blindness. If an operation is indicated, the cataracts should be removed from both eyes before 3 months of age and ideally within the first few days or weeks of life. The child should be fitted with a contact lens or aphakic glasses as soon as possible for maximal stimulation of the developing macula. Fairly good results can be obtained in patients with bilateral cataracts.
If a child has a unilateral cataract, the situation is considerably altered. If the patient has one normal eye or one with good useful vision, good vision is unlikely to develop in the eye with the cataract, either with or without a cataract surgical procedure. For any attempt at visual rehabilitation, the procedure must be performed as early as feasible (within weeks), the patient must wear an aphakic correction (usually a. contact lens), and occlusion therapy (with a patch) must be applied to the normal eye to stimulate development of visual potential in the aphakic eye. Therapy must be continued during the early years of visual development, and care must be taken to avoid causing amblyopia in the good eye. Complete cooperation from the parents isessential. Before deciding on surgical removal of the cataracts, the parents should understand that forcing the child to use the contact lens and occlusion therapy may cause social damage or psychologic damage in their relationship with the child. A recent study reported good visual acuity with an aggressive early approach,
- Beller R
- Hoyt CS
- Marg E
- Odom JV
Good visual function after neonatal surgery for congenital monocular cataracts.
but these results have not generally been reproducible. Intraocular lenses are being used in special circumstances in children, although amblyopia and other problems related to intraocular lenses remain a persistent problem.
Visual acuities of monocular IOL and non-IOL aphakic children.
A newer approach has been a refractive corneal operation (epikeratophakia),
- Friedlander MH
- Safir A
- McDonald MB
- Kaufman HE
- Granet N
Update on keratophakia.
which will be discussed later in this article.
Patients with congenital cataracts frequently have other general medical diseases or ocular diseases (such as myopia, retinopathy, or nystagmus). Glaucoma, retinal detachment, and secondary membranes are frequently late complications that hamper the visual success of the procedure, and this outcome fosters a conservative approach to unilateral cataracts by most practicing ophthalmologists.
- Toyofuku H
- Hirose T
- Schepens CL
Retinal detachment following congenital cataract surgery. I. Preoperative findings in 114 eyes.
Open-angle glaucoma following surgery for congenital cataracts.
Cataracts in Adults.
The major indication for surgical removal of cataracts in adults is the need to improve vision.
Indications for cataract surgery: psycholinguistic considerations.
Removal of cataracts (even though they are not far advanced) may be necessary in several other circumstances—for example, to facilitate the visualization of the ocular fundus (in order to monitor glaucoma or in preparation for photocoagulation therapy in diabetic retinopathy), to remove a foreign body embedded in the lens, to prepare for vitrectomy and surgical repair of retinal detachment, or for a variety of pathologic conditions in which the lens is threatening the viability of the eye. The last-mentioned conditions include phacolytic glaucoma (in which the fluid of the lens escapes and causes intraocular inflammation and glaucoma), rupture of the lens that causes phacoanaphylactic endophthalmitis (a reaction that results from prior sensitization to lens protein), or swelling of the lens and consequent crowding and compromising of the anterior structures of the eye. Both the physician and the patient must have a clear understanding of the objective of the surgical procedure so expectations are appropriate.
No absolute or exact visual requirements can be cited for recommendation of a routine cataract operation. The decision for surgical intervention depends on the patient's needs, the desired activity and recreational level of the patient, the symmetry of the disease process, conditions of the other ocular structures, the general health of the patient, and appropriate informed consent with reasonable expectations of the patient. One useful approach is to consider this elective procedure from the stance of the devil's advocate: can the patient function with the present level of vision, and can the patient and physician stand by their decision in the face of a serious complication that may lead to permanent blindness? Patients in the working age group (for example, physicians and surgeons) may have their livelihood threatened by decreased visual acuity or loss of binocular vision, and consideration of cataract extraction in patients with 20/30 or 20/40 vision is not rare. The posterior subcapsular cataract, which occurs particularly frequently in middle-aged persons, can profoundly affect reading vision, whereas the nuclear sclerotic cataract affects distance vision.
If the patient believes that visual performance is adequate, surgical correction should not be considered. An exception to this general rule is the presenile or senile patient who lives alone or in a nursing home and who may be coping with multiple medical or social problems and does not realize the extent of the visual loss. Under these circumstances, it is gratifying to restore vision and provide a new life for these elderly patients. Balancing these successes, however, are the elderly persons who have associated ocular disease (such as macular degeneration, glaucoma, or retinopathy) that cannot be accurately assessed preoperatively. Even though cataract removal is technically successful, vision in these patients remains limited, and frustration and depression prevail.
With the availability of newer and better surgical techniques for cataract removal, in conjunction with an aging population and increasing patient demands, a more liberal trend has evolved in performing cataract operations. In some patients, cataract extraction does not appreciably improve the quality of life. Tissue is not generally available for postoperative analysis, and even if it were present, visual function cannot be determined on the basis of a pathologic examination.
If the patient has a unilateral cataract, the decision to proceed with operative removal is even more complicated for the patient and the physician. In this circumstance, the patient must use a contact lens or an intraocular lens postoperatively in the affected eye to restore binocular vision. Although an active person may require this binocular vision, such an outcome is not necessarily appropriate for an elderly patient confined to a nursing home or a wheelchair who may not even appreciate the improved visual acuity. Certain broader social and financial issues may be forced into the decision-making process in the future.
The final decision about surgical removal of cataracts depends on the age and the occupation of the patient; the skill, experience, and surgical philosophy of the surgeon; and the expectations of the patient or the environment in which the patient lives.