Symposium: Modern Aspects of Cataract Operations f



INTRAOCULAR LENSES-CURRENT STATUS NORMAN S. JAFFE, MD MIAMI BEACH, FLORIDA An attempt is made to depolarize current positions regarding intraocular implant lens surgery by presenting a reasonable list of advantages and disadvantages of the procedure. A current position on this controversial subject is presented and is based on currently available knowledge. Although this is a personal view, it is hoped that a middle ground can be created which would be acceptable to advocates and opponents of lens implant surgery.

TWENTY-EIGHT years have passed since Ridley implanted his first intraocular lens. Ten years have passed since I implanted my first intraocular lens, an experience initiating more than 2,000 lens implantations. Nonetheless, even the most enthusiastic advocate of this procedure would agree that this has polarized the American ophthalmic community like nothing else in recent memory. The intraocular implant lens was born in controversy, has been controversial, and remains controversial. An attempt is made in this paper to depolarize current positions by presenting a reasonable list of advantages and disadvantages of the intraocular implant lens and

Submitted for publication Sept 26, 1977. From the Bascom Palmer Eye Institute,University of Miami School of Medicine. . . Presented at the Eighty-second Annual Meeting of the American Academy of Ophthalmology and Otolaryngology, Dallas, Oct 2-6, 1977. Reprint requests to 1680 Meridian Ave, Miami Beach, FL 33139.


presenting a current position on the subject. This is done with the full realization that no single person can speak authoritatively for a huge community of ophthalmologists and with the further understanding that progress is dynamic so that today's vogue may be tomorrow's obsolescence. However, it may be possible to place the intraocular implant lens in reasonable perspective acceptable to the broad spectrum of American ophthalmology. Objectivity based on experiences should guide the future positions oflens implantation. The following statements are those of one ophthalmologist and are not intended to reflect unfavorably on positions assumed by others.

ADVANTAGES OF THE INTRAOCULAR IMPLANT LENS 1. In uncomplicated cases, the quality of vision far exceeds that of a routine cataract extraction corrected with spectacles.

Image-size magnification is virtually eliminated, spatial disorientation is nonexistent, pincushion distortion is absent, and there is no restriction of the peripheral visual fields. The vision of the pseudophakic eye resembles that of the normal phakic eye more closely than any other method of optical correction of aphakia. In addition, constant adjustment of aphakic



spectacles is eliminated. None of the adverse effects of aphakic spectacles on the patient's coordination in simple manual tasks and mobility are apparent in pseudophakia. 2. For those unable to manage a contact lens (elderly, arthritics, those with parkinsonism, hemiplegics, mentally retarded), intraocular implant lens surgery is often the procedure of choice.


4. The patient with a successfully implanted intraocular lens in one eye usually is more mobile than a patient who is bilaterally aphakic and wearing spectacles.

This is an advantage attested to by thousands of patients who have undergone intraocular lens implantation. Contact lenses became popular for aphakic patients because of the disadvantages of spectacles. Intraocular lenses became popular When cataract extraction is indi- because of disadvantages with both cated in a patient with a predom-. contact lens and spectacle lens inantly unilateral cataract, an intra- correction of aphakia. In retireocular lens is the best solution for ment communities where a high those patients who are unlikely to number of aphakic patients live in succeed with a contact lens. This close proximity, it is readily apparapplies particularly to elderly, in- ent that the patients with intrafirm, and mentally incompetent ocular lenses and contact lenses patients. The younger, healthy pa- (when they can be successfully tient is a suitable candidate for a managed) are more mobile than contact lens. those wearing aphakic spectacles. The psychologic adjustment to 3. In an elderly patient with aphakia has been considerably bilateral cataracts, unilateral intra- eased by the intraocular implant ocular implant lens surgery may be lens. adequate for the patient's needs. 5. Long-wear contact lenses are Elderly and infirm patients often still unproved. manage well with an intraocular lens in one eye. This is far superior Although claims have been made to a unilateral aphakic spectacle for several years that long-wear after routine cataract surgery in contact lenses will replace the one eye. Some patients require intraocular lens, we are no closer binocular vision. This may be ac- to this realization than we were complished with a contact lens in five years ago. Long-wear contact one eye and an intraocular lens in lenses are successful in a signifithe other. A reasonable alternative cant number of patients but probis bilateral routine cataract extrac- lems still arise in an unacceptably tion with spectacles for both eyes. high number of patients. UnforOnly time will tell if bilateral lens tunately, if cataract extraction is implantation in the younger, healthy performed with the expectation patient, even with a suitable inter- that a contact lens will be worn, val between operations, is justified. failure to succeed is highly disapHowever, if a single operation pointing. The options facing the using an intraocular lens can meet patient (viz, no correction for the the needs of an elderly patient, it aphakic eye, a cataract spectacle is a definite plus for the procedure. with a balance lens for the opposite



eye, or a secondary implantation of an intraocular lens) are less satisfactory than the primary implantation of an intraocular lens.

DISADVANTAGES OF THE INTRAOCULAR IMPLANT LENS 1. The operation is technically more difficult than a routine cataract extraction.

This should be readily apparent since the process of lens implantation commences where the routine cataract extraction ends. It requires a high degree of skill and judgment. Whether one prefers an intracapsular or an extracapsular cataract extraction, a bulging vitreous without actual vitreous loss is not a serious problem so long as lens implantation is not planned. However, one can imagine the danger to the corneal endothelium and the anterior hyaloid membrane if an implant is to be inserted. Techniques are available to safely implant a lens in such a situation but they require intense training and extraordinary skill. 2. The rate of complications is therefore greater, although only slightly greater, according to present knowledge. This varies with the skill of the surgeon. The additional intraocular maneuvers required in the implantation of an intraocular lens after the cataract is removed expose the corneal endothelium and anterior hyaloid membrane to greater risk of injury. The incidence of postoperative corneal edema and operative loss of vitreous are higher than after a routine cataract extraction.


Skillful surgery can restrict this difference to a minimum. However, most reports indicate that endothelial cell population is reduced to a greater degree after lens implantation than after routine cataract operation and, if vitreous loss occurs, there is a higher rate of cystoid macular edema and retinal detachment. 3. Some postoperative complications associated with both intraocular implant lens surgery and routine cataract extraction are more serious with the former, eg, flat or shallow anterior chamber and retinal detachment. A flat or shallow anterior chamber after a routine cataract extraction, while not to be taken lightly, usually does not require urgent therapy. If this complication does not respond to observation or medical therapy over a period of days, minor surgical intervention usually corrects the problem. However, when an intraocular implant lens is in situ, this is a surgical emergency. Contact with the back of the cornea can easily result in permanent corneal decompensation. Immediate treatment of the cause of the anterior chamber depth abnormality is mandatory. Some reports indicate that the rate of reattachment of the retina is the same whether or not an implant is present. Others contend that the rate of reattachment is lower in pseudophakia. However, there is little contention with the observation that visualization of the retina is more difficult with an implant in situ since pupillary dilatation may be inadequate. This is made even more difficult if a posterior capsule or other lens remnants are present.



4. Closer follow-up care, both short and long term, is required, especially if we are to assess the risks and advantages of intraocular lenses. Since a relatively large foreign body remains inside the eye, it becomes necessary to give the patient closer follow-up care than that given for a routine cataract extraction. This is both for the short and long term. The eye may show more early or late recurrent iritis. There may be evidence of intermittent contact between a haptic support or even the optical portion of the implant. A subluxation of the implant may go unrecognized. Equally important from the point of view of close observation is the information which becomes available. This data is useful in assessing the risks and advantages of intraocular lenses both for short and long periods. 5. Colleague resistance. Complications are more severely criticized. Because the intraocular implant lens is still a controversial subject, criticism is often emotionally stimulated. A colleague who elects not to perform lens implantation because he feels insecure with the surgery or is unconvinced of its advantages tends to be more critical of the procedure. Complications which occur after lens implantation and routine cataract extraction, such as retinal detachment, hyphema, and cystoid macular edema are often not judged impartially. 6. Dependence on quality manufacturing. This is a significant disadvantage. An implant lens is placed


inside the eye where it is intended to remain for a lifetime. The quality of the optics, the quality of the design, and the absolute assurance of sterility of the implant are crucial. Breakdowns in quality assurance have occurred in the past and will probably result in the future. The eagerness of manufacturers to enter what they consider to be a lucrative market makes it difficult to police the traffic. This is a definite disadvantage of the intraocular implant lens. CURRENT POSITION 1. Intraocular implant lens surgery should be performed only after adequate training.

The curriculum of every residency program in ophthalmology should include lens implant surgery. Careful supervision of the resident ophthalmologist by an experienced lens implant surgeon must be done. Supervisory personnel must accept this obligation with the realization that a great responsibility rests with them. It would be a disservice to permit less skilled surgeons to progress to lens implantation during their period of training. They should be discouraged from attempting this surgery. Courses for the graduate ophthalmologist must be upgraded. These courses must place the intraocular implant lens in perspective. Minimally, they should include instruction in the materials which constitute an implant, indications and contraindications for the surgery, surgical technique including animal laboratory experience, the management of complications, and information concerning manufacturers and their products.



2. For less experienced surgeons, the initial indications should be extremely conservative. The beginning implant surgeon will never regret a cQnservative start in lens implant surgery. Extremely elderly patients should be selected because of their shorter life expectancy and the lesser tendency for vitreous bulge after the cataract is extracted. Where extracapsular cataract surgery is planned, the procedures should not be overly complex. Difficult phacoemulsification procedures should be converted to a standard extracapsular method with a larger incision. Miotic pupils and eyes with anterior segment abnormalities should be avoided. There should be a logical progression to more complex procedures and cases based on the surgeon's personal experience. 3. Surgery should be restricted to those patients not likely to manage a contact lens. Examples of such individuals have been cited earlier. Although the rate of complications is only slightly greater with lens implantation than routine cataract surgery, it is the majority opinion that lens implantation is less safe. There are patients who would obviously be poor candidates for a contact lens anc:;l others who could reasonably be expected to manage a contact lens. Extended-wear contact lenses are an alternative to intraocular lenses but their long-term safety is still unproved. In the, final analysis, the decision as to whether the patient is a reasonably good candidate for a contact lens rests with the surgeon.


4. Surgery on two eyes close together is unacceptable. There is a nearly equally divided opinion on the acceptability of routine cataract extraction in both eyes within a week. Good arguments can be presented to support both points of view. The situation is different with intraocular lenses. Serious complications present in both eyes of the same patient are more difficult to correct in the case of intraocular lenses. It is difficult to define what one means by operating on two eyes close together. In general, the time hiatus between operations in an elderly patient can be shorter than that in a younger patient. Once again, the standard for a reasonable time interval between operations on both eyes must be established by the surgeon. However, most ophthalmologists would agree that operations close together are unacceptable, based on present knowledge. 5. The patient's decision ' to undergo intraocular implant lens surgery should be based on a reasonable informed consent which includes the advantages and disadvantages of the procedure as well as alternatives. The requirement for an informed consent by the patient is currently mandatory. However, even if this were not the case, the patient's decision to undergo lens implant surgery should not be based on unscientific information disseminated by the news media. The decision should be made only after a careful explanation of the advantages and disadvantages of the procedure as well as the advantages


85 1978


and disadvantages of alternative procedures. The surgeon must present this to the patient as objectively as possible in language \\j,hich the patient or his family can uhderstand. 6. A surgeon who performs an adequate cataract extraction but feels insecure with the demands of intraocular implant lens surgery or is unconvinced of its benefits should not perform lens implantation. It is ironic that the possibility now exists that a surgeon can be criticized for not implanting a lens in instances considered acceptable by a lens implant surgeon. It is certainly not in the patient's best interest for a surgeon who considers lens implantation beyond his expertise to perform the surgery. Many ophthalmologists are un convinced of its benefits. It would be improper for them not to be guided by their own experience and judgment. In fact, since lens implantation is still a controversial procedure in the minds of many, surgeons on both sides of the issue should respect each other's opinion and not confuse the patient by making unscientific remarks about the surgery. Implant surgeons must be especially respectful of their colleagues who do not do the operation since the latter are often under pressure from patients who want the procedure. It would be unrealistic to expect full objectivity on both sides, but one can expect the advice afforded the patient to be based on an honest assessment of the procedure by a consulting surgeon.

7. There are still too many breakdowns in good manufacturing processes.


This has been discussed above. The implant surgeon must assume the role of watchdog over industry. He should expect quality optics, quality design, and absolute assurance of sterility from the manufacturer. Breakdowns in quality assurance must be reported to the American Intra-Ocular Implant Society, which has played a valuable role in the past in rapidly apprising its members of problems. The section on Medical Devices and Diagnostic Products of the Food and Drug Administration should be expected to monitor the manufacturer and his products. The lens implant surgeon should cooperate fully with this federal agency, whose role it is to protect the patient as well as the surgeon. 8. The long-range results are still uncertain. There is a need for welldocumented retrospective studies. The uncertainty which exists over the long-range safety of the intraocular implant lens is a result of a paucity in the medical literature of well-documented retrospective studies of a particular implant procedure using a specific implant. Techniques . and implants have changed frequently, making it difficult to assess the long-range safety and efficacy of a particular implant technique using a particular implant. Implant surgeons must be encouraged to collect data and report their long-term results. Without this, patients cannot be promised what is not known. 9. The short-term safety is still controversial. There is a need for well-controlled prospective studies. Most lens implant surgeons are convinced of the short-term safety



and consider that the risk is only slightly greater than a routine cataract extraction. Some lens implant surgeons and many nonimplant surgeons consider the risks to be significantly greater. This difference can be best resolved by well-controlled prospective studies. The National Eye Institute of the National Institutes of Health is ideally suited to conduct such studies.


current position which exists in the minds of others must be expected to change in the future. This change will be based on continued accumulation of experience in the field of lens implant surgery.

10. It is inevitable that the current position will change in the future.

It is hoped that proponents of opposing points of view can place the intraocular implant lens in reasonable perspective. This will help defuse the sometimes heated controversy over the procedure and insure an orderly and sequential growth of intraocular lens implantation.

Progress is dynamic. The current position expressed here and the

Key Words: Intraocular lenses; current status; advantages; disadvantages.

Intraocular lenses--current status.

Symposium: Modern Aspects of Cataract Operations f f f INTRAOCULAR LENSES-CURRENT STATUS NORMAN S. JAFFE, MD MIAMI BEACH, FLORIDA An attempt is mad...
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