Major Ambulatory Surgery of the Ophthalmic Patient

Major Ambulatory Surgery of the Ophthalmic Patient

Major Ambulatory Surgery 0039-6109/87 $0.00 + .20 Major Ambulatory Surgery of the Ophthalmic Patient J. Stuart McCracken, M.D. * Ophthalmic surg...

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Major Ambulatory Surgery

0039-6109/87 $0.00

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.20

Major Ambulatory Surgery of the Ophthalmic Patient J.

Stuart McCracken, M.D. *

Ophthalmic surgery originated as an outpatient endeavor, as did most surgical procedures. This discussion traces how ocular surgery found its way into the hospital setting and how it has returned to an ambulatory setting. Of course, this does not mean that couching has found favor again, nor do ophthalmologists treat postoperative eyes with poultices of egg whites. As a specialty, ophthalmology has undergone an incredible revolution during the past decade in both technical advances and understanding of disease processes. Many of the technical advances have occurred on the surgical side of ophthalmology. These include, among others, the application of differing wavelengths of the laser to the retina, the Kelman phacoemulsification instrument to the lens, and the Machemer vitrectomy system to the vitreous. Other less dramatic advances have occurred, among them the utilization of operating microscopes and finer, stronger sutures that have allowed the earlier ambulation of patients to the benefit of all concerned. Ambulatory surgery correctly implies an accelerated rehabilitation, not simply a shorter stay under the roof of a medical building. Ali ibn Isa had his patients remain in bed for 7 days while they recuperated from a couched lens procedure. 2 His incision could not have been much larger than that of Kelman's 3 mm incision for the phacoemulsifier cannula, and this same small incision was hailed as a new advance that would allow the patient to be discharged earlier than a week.

HISTORICAL SUMMARY

The first ophthalmic procedure known to have been performed was couching, or dislocation, of the crystalline lens. While the standard teaching *Attending Physician, Division of Ophthalmology, Durham County General Hospital, and Member, Board of Directors, Durham Ambulatory Surgical Center, Durham, North Carolina

Surgical Clinics of North America-Vol. 67, No.4, August 1987

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and practice for postoperative care included 7 days of rest for the patient, 2, this presumably was accomplished in the patient's dwelling. With an incision as small as that of a couching stab wound, healing undoubtedly occurred quickly even in the eras prior to medical cleanliness. Therefore, it seems that we can call the early cataract procedures ambulatory in practice, if not in intent. As the centuries progressed, the improvements in ocular surgery changed the nature of ophthalmology. Cataracts were still the primary ocular procedure, except for perhaps enucleation. Jacques Daviel (1696 to 1762) is credited with the invention of actual cataract removal, requiring a much larger incision than that needed in couching, or Antyllus' and Ammar's suction procedure. I Because corneal sutures for wound closure were not invented until 1866 by Henry Williams,18 the need for immobility of the postoperative cataract patient suddenly increased. The practice of the extracapsular cataract extraction in Europe became more widespread by means of itinerant barber-surgeons, the most famous of whom was Baron Michael de Wenzel. Although he and his son, Jakob, remained long enough to attend to their postoperative patients, apparently many of the itinerant cataract surgeons did not, giving rise to the first accusations of ocular surgeons abandoning their patients! Again, although these patients definitely required a longer and quieter recovery period, they generally remained in or near their domicile. Interestingly, the Baron was perhaps the first eye surgeon to advertise the "skill and ease with which the operation is performed" and "guaranteed the success of the operations" in notices published in local newspapers where he visited. 5 , 8 Although there was reason for hospitalization of these patients because of the larger extracapsular incision, they received variations of nonhospitalized ambulatory care. With the rise of university centers of medical training and their increasing prominence in the major cities of Europe, the shift in surgical care of patients from the outlying areas to the city hospitals began. The realization of the germ theory and the early use of antisepsis allowed the hospital to be seen as a place of healing rather than a place for the moribund. In the major centers of medical education-Vienna, Paris, and London-improvements on existing procedures occurred, such as Graefe's cataract knife. Also, other procedures were invented, attempted, and proved. 9 During this time, many concepts of medical care were firmly entrenched, some of which are alive today. With the onset of sterile technique, antisepsis, and actual operating rooms, the surgeons of the day were correct in promoting the ideas that all surgery should be done in the hospital, because there was no better place. Logically, the postoperative care should also be centered in the hospital. Specialty hospitals, physician-owned and operated, became the standard way of receiving medical care for the wealthy. Eye surgery was no exception, and throughout Europe and America eye hospitals thrived; Interestingly, the person credited with perfecting the intracapsular cataract extraction, Colonel Smith, based his experience on numerous

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extractions in India, on presumably ambulatory patients. 17 The safety of this procedure having been proved, it became the standard inpatient procedure, with minor variations, for nearly 80 years, until better instrumentation arrived.

THE TECHNOLOGIC EXPLOSION With the major exceptions of sutures, sterile technique, and antibiotics, the cataract extraction procedure in the early 1960s had not changed for nearly a century. The microscope was just beginning to come into use in a standard way, but the use of loupes was still very prominent. Other procedures, such as strabismus surgery, iridectomy for glaucoma, retinal reattachment, and corneal grafts, were all done without the operating microscope. During the next 2 decades, a virtual explosion of increased abilities occurred through technologic advances. These include the adaptation of the microscope and laser to ophthalmic surgery, the introduction of stronger and finer suture materials, and the invention of the phacoemulsifier, the intraocular lens, and the vitrectomy unit. Although all of these were introduced with the purpose of either perfecting a procedure or improving the results thereof, nearly all of the recent advances have furthered the concept of ophthalmic ambulatory surgery. For example, because 10-0 nylon sutures are available, a cataract incision is secure enough for a patient's ambulation that day. The increasing use of the extracapsular cataract procedure has markedly decreased the incision size and the morbidity caused by vitreous in the anterior segment. The use of phacoemulsification has reduced the incision size to little more than that of the lens couchers. The availability of antibiotics, steroids, and viscoelastic substances all provide an extremely low incidence of surgical complications after cataract and glaucoma surgery, to say nothing of corpeal surgical procedures. There used to be n'b hope for patients with longstanding diabetic vitreous hemorrhages and retinal detachments; now several procedures exist that can restore ambulatory vision even in seemingly hopeless situations.

EARLY TRENDS TOWARD AMBULATION With these improvements, the standard postoperative stay in a hospital was also being re-evaluated. It had not been lost on ophthalmologists that for cataract patients, who were usually elderly, a long stay in a hospital bed, often immobilized, was not good for the patient. As early as 1886 there were reports of early ambulation following cataract surgery. 6 Many other eye surgeons noted that early ambulation of cataract patients was not detrimental, both in this country and in Hong Kong prior to 1960. 21 In Pakistan, Christy7 reported on three groups of 1000 patients, with one group allowed to ambulate without restriction and the others bedridden for either 1 or 8 days. He noted no differences in each group's

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results, all having 94 per cent attaining good visual acuity. More reports in the ophthalmic literature attested to the success of early ambulation for cataract surgery in this country, Japan, Germany, and Senegal. 21 In 1974, Galin reported on a 15 year review of progressive ambulation of postoperative cataract patients in which prospective groups of patients were either kept in for 9 days or discharged at shorter and shorter intervals. By comparing consecutive groups of patients, at no time was there any increase in complications in the early discharged group, even the ones sent home the day of surgery. These were intracapsular procedures prior to the use of intraocular lenses. 10 Williamson reported on a series of patients both without20 and with24 . 25 intraocular implants with uniformly excellent results. Williamson was one of the first ophthalmologists to set up his own ambulatory unit, which was in Venice, Florida; and he was the first eye surgeon to convert to outpatient cataract surgery entirely.

GOVERNMENTAL CONCERNS The Outpatient Ophthalmic Surgery Society was formed in 1981. Williamson, one of the original members and president of the Society, states that the purpose was "gathering and sharing information and knowledge about all aspects of outpatient surgery in order to provide the best possible care for our patients at the lowest possible cost. "19 Until this period, the viewpoint of health insurers and Medicare in the United States was that all procedures of importance should be performed in an accredited hospital. Even during the time of technologic advancement in eye surgery, a stipulation for insurance coverage was that the procedure be done in a hospital so that the newer changes could come under a quality assurance committee. 14 Finally the federal government recognized that outpatient cataract surgery could be reimbursed by Medicare if performed in an ambulatory surgical center. Requirements were enacted that provided standards for safety, certification, professional credentials, and accreditation. 16 Since 1982, when the first freestanding ophthalmic surgical center was accredited in Hayward, California, more than 50 centers have become operational. This does not include many other freestanding surgical centers that serve many specialties. Once the success of the outpatient cataract procedures became obvious, the enactment of Federal Regulation 42CFR, part 405, volume 49, number 129, in 1984 set up Diagnostic Related Groups for hospital reimbursement of, among others, cataract patients, stating that prior approval for Medicare patients be required. 16 Requirements for outpatient cataract procedures are to be established in the fall of 1987. 12 Previously, each state was allowed to contract for the services of a professional review organization that would administer the prior approval procedure. Since that time, in North Carolina and many other states, unless a patient has a significant medical problem, even an overnight stay following cataract surgery (but not many other ophthalmic procedures) will

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be reviewed and payment denied. This has markedly increased the number of outpatient cataract procedures in these states. Obviously the emphasis -on outpatient and ambulatory surgery in ophthalmology has been on cataracts, and it has been well established that, unless other medical situations occur, the current cataract procedure is primarily an ambulatory procedure. Other ophthalmic procedures either have evolved into ambulatory procedures or are in a position to be classified as such. After 1982 the Health Care Financing Administration expanded the list of surgical procedures for which payments can be made for services and facility charges. Although the list is to be shortened in the near future, it includes "virtually all ophthalmic surgical procedures. "15

AMBULATORY OPHTHALMIC PROCEDURES In 1981 the membership of the Outpatient Ophthalmic Surgical Society was asked which procedures could be safely done on outpatients. The response was that all current procedures could be, except for three. These were orbital exenteration, gas/air injection for reattachment of a retina, and transcranial orbitotomy.22 Brief mention is necessary concerning my own thoughts in regard to the discussion of the appropriate ambulatory classification of the following procedures. Although in the best possible situation, nearly any ophthalmic procedure can be done on an outpatient, this does not mean that the procedures should always be done that way. There are, and will always be, situations in which any of the following procedures should be done on an inpatient basis. Cataract and Intraocular Lens Procedures As has already been stated, cataract procedures are ambulatory ones. Glaucoma Procedures Glaucoma procedures, because the techniques, incisions, and closures are so similar to cataract procedures, are easily adaptable to an ambulatory basis. While many professional review organizations (PROs) do not require preadmission approval for trabeculectomies, there is no question that these procedures would not require admission. Needless to say, any laser procedures for the treatment of glaucoma are ambulatory in nature. Strabismus Procedures Strabismus procedures have gradually become outpatient ones in the pediatric population over the past decade, because the general anesthesia times have been short enough to allow the patients to recover within a few hours. Adult patients tend not to tolerate general anesthesia as well but can be sent home just as general anesthetic patients in other fields are. The use of adjustable sutures requires the patient be awake and alert several hours following the procedure, and that would also allow ambulation. The use of botulinum toxin injections is definitely ambulatory in nature.

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Corneal Procedures Corneal procedures are also adaptable to ambulatory classification. Obviously superficial operations such as pterygium removal, radial keratotomy, and keratomileusis can be done on an outpatient basis because the cornea usually is not penetrated. On the other hand, penetrating keratoplasty, with or without cataract removal, and whether an intraocular lens is used, may still be an overnight procedure. This is not believed by all corneal surgeons. 22

Orbital Procedures Orbital procedures are being performed less often because of the increased use and availability of computerized tomography. However, the orbital procedures done may involve enough potential for later bleeding that an overnight hospital stay might be wise. This category includes enucleations, which require pressure dressings, and exenterations, for the same reasons. With the advent of magnetic resonance imaging (MRI), the number of exploratory orbital procedures will probably diminish further. Oculoplastic Procedures Plastic and reconstructive procedures often involve the entire orbit and, in those that have a risk of hemorrhage because of the extent of the procedure, an overnight stay often may be indicated. Less involved plastic procedures such as lid operations will continue to be outpatient procedures. Retinovitreous Procedures Retinal procedures such as reattachment operations can be managed as ambulatory procedures, unlike in years past. The advent of cryotherapy and silicone exoplants has allowed more secure reattachment procedures that allow a patient to be discharged the day of surgery. Often the procedure can be accomplished under local anesthesia, allowing a more rapid recovery. Other retinal procedures are not as easily classified. Procedures for irradiation of choroidal tumors by cobalt exoplants that must be removed after a length of time might do as well in an inpatient setting. Although the vitrectomy procedure in itself causes little trauma to the eye, the reasons for using it may override any ambulatory ideas the patient may have. For example, the most common reason for elective vitrectomy in the United States is for diabetic retinopathy complications. In general these are patients who do not tolerate surgery well, and it probably benefits them to be in the hospital for management of the other complications of diabetes. If the retinal procedure involves the use of expansile gases, admission is required for intraocular pressure monitoring. The use of silicone oil may also require admission, as does the use of experimental retinal tacks. Vitrectomy and membrane dissection or peeling may in cases of trauma allow the patient to be discharged that day. More recently, Landers and coworkers l l showed that some vitreous fluid-air exchange procedures can be performed in the office at the slit lamp.

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Laser Procedures Virtually all laser procedures, although they can be done on inpatients as part of the hospital treatment, do not require hospitalization. Most procedures do not require more than topical anesthesia, and the morbidity associated with these procedures is small. This category includes panretinal photocoagulation, focal treatment for diabetic retinopathy, iridotomy, and trabeculoplasty for glaucoma, all with the argon laser. The krypton wavelengths are also useful in macular disease treatment. The neodymium:YAG laser has been approved by the Food and Drug Administration for posterior capsulotomy and iridotomy. ADVANTAGES OF AMBULATORY OPHTHALMIC SURGERY In my own practice, the inpatient:outpatient ratio for cataract procedures 4 years ago was 90:10 per cent; today it is 5:95 per cent. Part of the reason is due to PRO regulations; it is simply easier to set up outpatient procedures without prior approval (although this is supposed to arrive for ambulatory surgery in 1987).12 The other reason is that having a relatively new freestanding ambulatory surgicenter available, and having it equipped with instruments with which I am comfortable, why not use it? The most apparent advantage to the use of an ambulatory facility is that patients like it, especially if they have known someone who has benefitted from one. Occasionally a patient asks to be hospitalized, but I have not had a single patient within the year resist being able to go home following the procedure. This is quite different from 5 years ago, when I had to talk patients into having a cataract procedure on our hospital's outpatient unit; because it had not been done before in our hospital, there was wariness on the part of some patients. Other advantages have been summarized by Williamson23 and Severin.16 In the age group of most cataract patients, problems arise that often occur in the hospital setting, the most striking example being the disorientation of unfamiliar surroundings. By staying at home, or with family, not only does the physician avoid late night phone calls from the ward nurse, but more importantly the patient does not undergo the anxiety of being away from home. PREOPERATIVE EVALUATION There are serious concerns that the push toward ever increasing outpatient treatment is not all good,3. 14 and I believe that what might be lost in the headlong rush is the medical evaluation of the patient. Although I welcome the abbreviated admission forms utilized in ambulatory centers, the temptation is very great to skimp on the nonpertinent physical examination. Therefore, as the son of an internist, I have my patients seen by their personal physician who sends me back the completed form shown in Figure 1. I include this in the patient's chart so that the anesthesiologist

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TO THE PATIENT: You have been scheduled for eye surgery. To obtain the best result for you, we must know your present physical status, present medication, and so on. We want you to visit your personal physician so that this form can be completed and returned to our office at least 1 week prior to your surgery date. Dear Dr. _ _ _ _ _ _ _ _ _ _ _ __ Your patient, , has been scheduled for ophthalmic surgery on , at Durham County General Hospital or Durham Ambulatory Surgical Center. I would appreciate your sending me a presurgical report about the patient's current physical status, to be used as the basis of the preoperative physical examination report and as a guide in treatment. Thank you for your cooperation in caring for this patient. Procedure: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___ Please check if the patient could tolerate surgery under: Local/standby anesthesia _ __ General Patients will be scheduled at the Durham Ambulatory Surgical Center UNLESS YOU FEEL THAT THEY SHOULD BE ADMITTED AT DURHAM COUNTY GENERAL. Blood pressure: Heart ______ Lung and chest _ _ _ __ Abdomen Limbs _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___ Pertinent laboratory tests: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___ Comments: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Drug sensitivities: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Preoperative medication preference (usually Valium and Fentanyl): _ _ _ _ _ __ The following laboratory tests will be ordered on admission unless you state otherwise: CXR, CBC, UtA, Chern 7, EKG. Add any that you feel are necessary: _________ List medications you would like the patient to continue, including dosages: Remarks: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___

Physician's Signature

Figure 1. A form used in preoperative evaluation.

has available both the internist's and the ophthalmologist's preoperative evaluation. In my opinion the most important aspect of an ocular patient's care is the perioperative cooperation with the patient's personal physician. PROCEDURE FOR CATARACTS

My current preference is to have the extracapsular cataract extraction performed under local/standby anesthesia, using intravenous short-acting agents during the lid block and retrobulbar injection of a lidocaine and bupivacaine mixture. Many variations on this exist. 16, 2.'l Following the completion of the procedure, the patient spends any-

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POSTOPERATIVE DISCHARGE INSTRUCTIONS Name _ _ _ _ _ _ _ _ _ _ _ __

Date _ _ _ _ _ _ __

1. Avoid straining, sudden movements, and lifting. Do not lift anything over 5 pounds unless your doctor says otherwise. 2. Do not get the eye bandage wet. The bandage will be removed or changed in the office the day after surgery. 3. Sleep lying on your back or turned to the unoperated side. Try not to sleep on the operated side for approximately 6 weeks. 4. After the eye bandage is removed, wear the protective eye shield or your glasses at all times. 5. Wait at least 1 week before shampooing your hair, then be careful not to get shampoo in the eye. 6. Do not drive until given permission by your doctor. 7. Medications Resume all medications that you normally take. For pain: Tylenol, two tablets every 4 hours as needed. Neptazane 50 mg pill at . This is supplied at the surgicenter; DO NOT TAKE IT IF YOU ARE ALLERGIC TO SULFA. 8. Your doctor will give instructions regarding your eye medications at the office the day following surgery. This includes the ointment given at the surgicenter. 9. Your appointment is with Dr.

from 8:30 to 9:15 A.M. on _ _ __

10. If any problems develop, your doctor may be reached at one of the following numbers: Office: 471-8495 Hospital page operator: 470-4000 Dr. Young: 489--3514 Dr. McCracken: 489-6692 Figure 2. Postoperative discharge instructions given to patients.

where from 45 to 60 minutes in the recovery area of the surgicenter, and receives an instruction sheet to take home; as shown in Figure 2.

THOUGHTS ABOUT THE FUTURE OF AMBULATORY OPHTHALMIC SURGERY What of future concerns? In a very short while, the standard for cataract surgery has swung from 2 nights in a hospital to as little as 2 hours away from a patient's home. Most ophthalmologists have an ambulatory facility available in their community, or their hospital provides a means for ambulatory possibilities. One change that looms ahead is the establishment of a network whereby many surgical centers can avail themselves of centralized purchasing and administration. As more prepaid health plans are established and compete for patients throughout the United States, more ways of efficient reduction of costs will be attempted and applied. Nationwide application of flat rate charges for both facilities and surgeons may become reality. Perhaps the overall reduction in cost will not occur at the expense of excellent patient care.

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In a recent address to the 38th Annual Chicago Ophthalmological Society, Paton stated that in the next century eye care will not be entirely in the hands of the ophthalmologist. The ophthalmologist will be but one of a large team of professionals that will be more efficient in processing more patients, but that will depersonalize the medical attention given to the patient. It is to be noted that Dr. Paton is the founder of an ophthalmic management company. 13 I am concerned that focusing on cost alone will save only in the shortterm and that increasing the size of an administrative body for ambulatory surgicenters, such as a large for-profit network, will only reduce the quality of care to the patient regardless of how glossy the ad campaign that is created for its support. This may not be the correct attitude from the administrative or marketing viewpoint in the current climate of medical competition, but had I wanted to sell cars or insurance, I would have become a salesman. In spite of these concerns for the future, the practice of ophthalmology and its patients have been well served by the advent of ambulatory surgery, probably because of the ease of adaptation of the specialty to the newer milieu. It remains for those of us who became ophthalmologists for patient care purposes to resist the market and governmental forces that may cause us to be "dentists of the eye."14 We must not allow the contribution of ophthalmology toward ambulatory surgery to become the weapon that fragments the physician's ability to decide the best care for the patient.

REFERENCES 1. Abul Quasim Ammar: In Wood CA (ed): The American Encyclopedia and Dictionary of Ophthalmology. Voll. Chicago, Cleveland Press, 1913, pp 316-318 2. Ali ibn Isa: Tadhkirat (Memorandum Book of a Tenth Century Oculist). English edition by Wood CA, Chicago, 1936. Facsimile edition by Birmingham, LB Adams, 1985, pp 183-187 3. Anderson WB Jr: Centered on the surgicenter. NC Med J 44:619, 1983 4. Benevenutus Grassus: De Oculis. English translation by Wood CA, Palo Alto, 1929. Facsimile edition by Birmingham, LB Adams, 1985, pp 33-36 5. Blodi FC: Review of J De Wenzel Jr: A Treatise on the Cataract. Facsimile edition by Birmingham, LB Adams, 1984 6. Bruns HD: The ambulant after treatment of cataract extractions with a note on postoperative delirium and on striped keratitis. Trans Am Ophthalmol Soc 14:473, 1916 7. Christy NE: Effect of early ambulation on the incidence of postoperative complications of cataract surgery. Am J Ophthalmol 49:293-297, 1960 8. De Wenzel J Jr: A Treatise on the Cataract. English translation by Ware J, London, 1791. Facsimile edition by Birmingham, LB Adams, 1984 9. Docherty PTC: Cataract extraction: Surgery at the crossroads. Semin Ophthalmol1:61-67, 1986 10. Galin MA, Baras I, Barasch K, et al: Immediate ambulation and discharge after cataract extraction. Trans Am Acad Ophthalmol Otolaryngol 78:0P-43-48, 1974 11. Landers MB III, Robinson D, Olsen KR, et al: Slit lamp fluid-gas exchange and other office procedures following vireoretinal surgery. Arch OphthalmoI103:967-972, 1985 12. P.L. 99-272: Consolidated Omnibus Budget Reconciliation Act (COBRA) of 1985, Section 9401 13. Paton D: Cost-conscious modern medicine progressing by a new set of rules. Ocular Surg News 4:3-4, 1986

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14. Reinecke RD: Outpatient surgery: Back to the barbershop? Arch Ophthalmol 103:26-27, 1985 15. Romansky MA: Special report: Governmental initiatives. Ocular Surg News 4:37, 1986 16. Severin SL: Outpatient cataract surgery. Semin Ophthalmol 1:130-135, 1986 17. Smith H: The Treatment of Cataract and Some Other Common Ocular Affections. Edition 2. Calcutta, Butterworth, 1928 18. Williams HW: Recent Advances in Ophthalmic Science. The Boylston Prize Essay for 1865. l3oston, Ticknor and Fields, 1866, pp 90-92 19. Williamson DE: High-quality, cost-effective care continues as primary OOSS goal. Ocular Surg News 4:3-4, 1986 20. Williamson DE: One thousand consecutive outpatient cataract extractions. Eye Ear Nose Thro;tt Monthly 54:37-49, 1975 21. Williamson DE: Ophthalmological surgery. If! Davis JE (ed): Major Ambulatory Surgery. Edition 1. Baltimore, Williams & Wilkins, 1986, p 295 22. Williamson' DE: Ophthal~ological surgery. In Davis JE (ed): Major AmblJlatory Surgery. Edition 1. Baltimore, Williams & Wilkins, 1986, p 296 23. Williamson DE: Ophthalmological surgery. In Davis JE (ed): Major Ambulatory Surgery. Editjpn 1. Baltimore, Williams & Wilkins, 1986, pp 297-298 24. Williamson DE: Outpatient cataract-implant surgery compared with outpatient cataract-standard surgery. Ann Qphthalmol 10:957-965, 1978 25. Williamson DE: Two hundred consecutive outpatient cataract intraocular lens implant operations. Ophthalmic Surg 8:29-34, 1977 Suite 203 2609 North Duke Street Durham, North Carolina 27704