Trends in Cataract Surgery Joseph W

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TRENDS IN CATARACT SURGERY JOSEPH W. EICHENBAUM, M.D. Assistant Clinical Professor Department of Ophthalmology The Mount Sinai School of Medicine New York, New York

RECENT EPIDEMIOLOGY C ATARACTS, OR LENS OPACITIES, are present in about 10% ofall Americans. Between the ages of 65 and 74 the prevalence of cataracts increases to about 50%, and for those over the age of 75 it increases to 70%.' In the United States cataracts are the major cause of self reported visual impairment. They are the third leading cause of preventable blindness. Although the impact of cataracts at the early stages can be lessened to some degree with glasses or contact lenses, surgery today, with lens implant, is the ultimate therapy that can be provided.' Based on current life expectancy, a person is more likely to undergo cataract operation than almost any other surgical procedure. This makes cataract surgery the leading therapeutic surgical procedure for Americans over the age of 65. It is estimated that about 1.25 million cataract extractions were performed during 1988 in the United States. More than one million cataract procedures are paid for each year by Medicare. The annual cost for cataract surgery and all associated care approximates $3 billion." 2 About 10% of all cataract surgery is done on an inpatient basis, resulting in about 125,000 hospitalizations annually. Ophthalmology is the leading category of surgical procedures in free-standing outpatient surgery centers. It accounts for 25% of all the surgery in these centers. The vast majority of the outpatient operations are cataract extractions with implantation ofintraocular lenses under local anesthesia.1'3'4 COUCHING AND THE VISION OF THE OLD WORLD Susruta, the first eye surgeon, who lived thousands of years ago in India, first described couching of cataracts. George Gorin's History ofOphthalmol- ogy provides a succinct surgical description: "It was done during the moderate

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Fig. 1. Couching of cataract in second half of the 16th century. Reproduced by permission from Gorin G.: History ofOphthalmology. New York, Publish or Perish (Raven), 1982, p. 36. season, preceded the day before by purgatives. The patient is seated and should look toward the nose. The point of puncture should be just outside the junction of the black and white on the temporal side.... The surgeon should hold the needle steadily and should puncture through the natural aperture [the pupil]. A correct puncture is indicated by exudation of a drop ofwater. An incorrect puncture will be followed by bleeding. After the cataract is reached it should be scarified with the needle till it is dislodged out of the visual field." (Figures 1 and 2)5 Although couching (or merely the displacing with a needle) of cataracts was the method of choice throughout Europe well into the 18th century, Arab surgeons of Baghdad had begun extracting cataracts back in the 13th century. Arab surgeons increased the Greek surgical armamentarium to 36 instruments, as described by Halifa in a text from 1266. They had devised a hollow needle knife as well as a glass tube to suck out cataracts. The ancient Arabians used corneal or scleral puncture with a

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A I B Fig. 2. Needle entry and contact sites in couching. A: anterior approach; B: posterior approach. Reproduced by permission from Gorin G.: History of Ophthalmology. New York, Publish or Perish (Raven), 1982, p. 26. sharpened glass tube inserted into the cataract. Using the mouth, suction was applied to such out the cataract.5'6 The ancients, including Galen, perpetuated the notion that the cataract was a condensation of fluid located in front of the pupil but emanating from the brain. The word cataract is Greek in origin. It is a down-rushing of water, a waterfall. Ibn Rushd Averoes, a Spanish Arab who was an Aristotelian scholar in the mid 1 OOs, was the first to suggest that the lens or cataract was not the photoreceptor organ of vision. He suggested that the retina contained the elements of visual perception.7 As early as the 11th century, Alhazen's Book ofOptics, written by Ibn al- Haitham in Cairo, rejected the ancient and pervasive emanation hypothesis. Because of the support of Plato and most of the ancient world for the emanation hypothesis, it was widely believed that the act of vision emanated from visual rays from the eyes. The visual rays traveled like sun rays or spider web threads to objects from the eyes. The skepticism of Aristotle and only a few others was ignored. Alhazen, a physicist during the 11th century, proposed the "camera obscura" or pinhole camera analogy to the eye. In his concept, light traveled from an object to the retina. The front segment of the eye focused the light on the retina. The retina then sent information to be assimilated into the brain. His treatise has the oldest diagrams of the visual system showing its components in relation to the brain. (Figure 3)7 Unfortu- nately, this level of sophistication in comprehension and methodology was not to resurface for nearly another 700 years. In 1543 Vesalius and others argued with the prevailing European wisdom.

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Fig. 3. The oldest diagram of the visual system showing its components and its relation to the brain. From the Book of Optics of Ibnal-Haitham (Alhazen), 1083; Reproduced by permission from Polyak S.L.: The Human Eye in Anatomical Transparencies, Kronfeld P.C. and McHugh G., editors. Rochester, NY, Bausch and Lomb, 1943, p. 82.

While this wisdom conceived of the lens as the site of vision, Vesalius and others maintained that the function of the lens was only to focus incoming light. Kepler, through mathematical analysis, Pater Scheiner, through direct observation, and Athanasius Kircher and Descartes independently demon- strated that the image was formed on the retina after being focused through the lens. They confirmed the hypothesis postulated by Alhazen centuries before.7 Georg Bartisch, according to some historians, was the "Father of Modem Ophthalmology." In 1583 he published the first printed textbook of ophthalmology. Bartisch portrayed in atlas format the anatomy of a model eye. He traveled extensively, using handbills to extol the virtue ofhis work in couching cataracts. Although he presumably enjoyed great success in his couching technique in many European cities as well as at the Vienna annual fair, the

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Fig. 4. Daviel's cataract extraction. Reproduced by permission from Gorin G.: History of Ophthalmology. New York, Publish or Perish (Raven), 1982, p. 47. guild of barber surgeons of Vienna intervened there. They refused to grant him a license and forced him to leave town.5 CATARACT EXTRACTION There were sporadic efforts in cataract extraction throughout the next century. These efforts included Blankaart (1669-1702) speaking of forceps removal through a superior corneal incision, circa 1700, and Charles St. Yves' spooning out ofthe lens through an inferior corneal incision in 1707.5 Despite these isolated attempts, it was Daviel who revolutionized the art of cataract extraction. In 1749, as the story goes, Jacques Daviel removed the lens of a steer in the presence of the king. Daviel used a knife incision in the inferior cornea, right and left corneal scissors (to enlarge the opening in the corneal scleral margin), a sharp needle to cut open the anterior lens capsule (just beneath the iris), a gold spatula to remove the lens nucleus, and a spoon and forceps to remove lens cortical remnants. Daviel left the posterior lens capsule in place still attached to the zonules (fine specialized connective tissue strands from posterior lens capsule to the ciliary body), and removed only the anterior lens capsule, the lens nucleus, and lens cortex, performing one of the first planned extracapsular cataract extractions (Figures 4, 5, and 6 for anatomic considerations).5 King Louis XV subsequently chose Daviel as his personal physician and established the first chair in ophthalmology, in Paris.5

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Fig. 5. American Academy of Ophthalmology clinical instruction slide showing extracapsular cataract technique. The cataract back capsule remains attached to zonular fibers, emanating black curved lines running to the more peripheral, darker ciliary body, behind the iris. The cataract also consists of the nucleus, central region, and cortex, stippled areas circumferentially around central area. In this diagram the cataract nucleus and cortex are removed linearly and the back capsule remains intact as the site for lens implant, vide infra. Reproduced by permission from San Francisco, American Academy of Ophthalmology, 1992, p. 41.

In the 1750s Daviel and, separately, de la Faye, who in 1752 designed the first cataract knife, removed cataracts and their capsule together (intracapsular cataract extraction). (Figures 5 and 6)5 They used gentle pressure from above and below, breaking the zonular attachments and extracting the cataract through an inferior corneal section. While in Rheims in 1751 Daviel performed 43 cataract extractions in three weeks. In 1752 he published a textbook on cataract extraction. By the end of 1756 Daviel had done 434 cataract extractions. Twelve percent had poor visual results. He cautioned against exerting excess pressure on the eye, vitreous loss, and iris prolapse.5 In London in 1753 Samuel Sharp is actually credited with the first performed intracapsular cataract extraction.8 However, this technique was not widely used until the early 1940s. Major advances in instrumentation and surgical sophistication in intracapsular technique developed after that early 1940s period.8 During the 1800s a number of ostensibly smaller advances facilitated the cataract extraction methodology. In 1801 Karl Himly described pupillary dilation to abet linear extraction.5 Pomard contributed three improvements to the Daviel procedure: the patient was operated on lying on his back, rather

Bull. N.Y. Acad. Med. CATARACT SURGERY 373

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Fig. 6. This sagittal section of a schematic eye (Fison's Pharmaceuticals, Rochester, NY, April 1989) illustrates the anatomy of the normal human lens. The lens capsule is the dark, outer elliptical line enclosing the clear lens. The lens cortex is the series ofcurved black partial elliptical lines just inside of the lens capsule. The lens nucleus is the clear central material. than sitting up; he used an instrument to fixate the globe during surgery; and placed the incision in the upper portion of the cornea rather than below.8'9 Through the mid 1 800s Frederick Jaeger and Carl Frederick Graefe developed safer, more controlled corneal incisions through the superior portion of the cornea.5 Graefe and Albert von Mooren began routinely to utilize preliminary iridectomy.5 This was to prevent postoperative glaucoma (increase in intraocular pressure due to pupillary blockage of aqueous flow from posterior chamber to anterior chamber). Antiseptic measures were introduced in 1870. Aseptic technique followed in 1889.5 Sigmund Freud and Karl Koller introduced topical local ocular anesthesia in 1884.5,1o In the early 1900s Henry Smith, Marcel Kalt, Ignacio Barraquer, and Daniel Kirby, among others, advanced extracapsular as well as the intracapsular cataract extraction technique." All were known as cataract surgeons who performed a large number ofoperations." Exact numbers ofintra versus extracapsular cataract extractions are not readily apparent." However, prior to 1940 extracapsular cataract extraction was the procedure of choice.8 One of its major drawbacks though was the lack of a reliable method to remove all ofthe lens cortical remnants. Even moderate amounts ofcortical remnants left behind resulted in dense membrane and secondary cataract formation. (Figure 7)12 While Wheeler or Graefe knives could be introduced into the eye

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Fig. 7. Reproduced by permission from Morgan, K.S.: Congenital and infantile cataracts. Current Science. 1: 8-14, 1990. A: Cataract anatomy preoperatively; note epithelial cells under anterior capsule and the upper and lower polar regions. B: Epithelial cells remaining in upper and lower polar rings begin to multiply. C: Epithelial cells germinate along posterior lens capsule (arrows) and in front of polar rings. D: Epithelial cells cover the entire posterior lens capsule and polr rings, that is a secondary cataract. Until the advent of the YAG laser in the early 1980s (page 18), secondary cataract and membrane formation limited the widespread use of extracapsular cataract surgery. to cut these membranes or secondary cataracts, there was no reliable method to prevent recurrence.8 Such maneuvers could also result in vitreous spilling with its own attendant potential for further scar tissue and ocular inflammation. The simple elegance of complete cataract removal, intracapsularly, along with peripheral iridectomy, leaving behind no lens elements that might opacify represented a significant advance in cataract surgery. Initially, the zonular attachments to the lens capsule were broken with gentle topical pressure from above with a muscle hook. The lens capsule was grasped with capsule forceps and linearly extracted.'3 A helpful analogy to visualize extracapsular versus intracapsular cataract extraction is to think of a piece of candy, with a sugar glazed shell over a chocolate covered peanut. In intracapsular surgery, the capsule, cortex, and nucleus (that is the glazed shell and chocolate covered peanut) are cut from the lens moorings, the zonules, leaving a clear optical conduit from the front chamber through to the back chamber of the eye. In extracapsular surgery, the front lens capsule (that is the glazed shell), has a window cut out of it. The nucleus and cortex (that is the chocolate covered peanut) are then removed, leaving the back lens capsule in place as a boundary between the front and back chambers of the eye.'4 In the 1950s an erysiphake, or lens suction cup apparatus, achieved some measure of popularity. Joaquin Barraquer in 1956 introduced alpha chymo- trypsin, an enzyme injected in minute quantities to lyse the zonular attach-

Bull. N.Y. Acad. Med. CATARACT SURGERY^ v 375I-7 ments to the lens for facile linear intracapsular cataract extraction. Tadeusz Krwawicz in 1961 introduced a cryosurgical apparatus to create an iceball on the lens and linearly extract the lens after the zonules had been broken manually or enzymatically lysed. Charles Kelman designed a cryoprobe with liquid nitrogen in the early 1 960s substantially to facilitate linear intracapsular cataract extraction. David Sudarsky and others originated even smaller, portable, pen sized cryoextraction devices. Loupes and coarse operating instruments gave way to operating microscopes and a vast (and still evolving) array of delicate, exquisite microscopic instruments.5 Frederick Verhoff introduced preplaced sutures to enable rapid wound closure. John McLean emphasized the advantages of wound closure with a staged, groove incision (and other surgeons practicing well before him).5'8 Myer Shlivic in the 1940s (and other surgeons practicing well before him) using the idea of peeling just the outer layer of an onion skin as an analogy to advance extracapsular surgery, developed a technique with capsule forceps to gently tear away the anterior lens capsule layer prior to nuclear delivery and cortical aspiration with a syringe."5 This extracapsular technique has been mimicked and substantially improved upon in the late 1980s with capsulorhexis.'6 In this capsulorhexis maneuver, a nearly circular tear is made in the anterior lens capsule using either a fine bent needle tip, special forceps, or forceps and scissor. The nearly circular tear and subsequent removal of the torn capsule create an open window with a clean edge capsular bag still attached to the zonules holding the capsule in place. The open window over the intact capsular bag facilitates removal of the cataractous lens as well as the placement of the implant. Along these lines technology provided several improvements. Henry Wil- liams in 1867 pioneered in the use of sutures.8 The Grieshaber Company developed sharp needles. Suture materials evolved from heavy chromic catgut through virgin silk, collagen material (dexon and vicryl), to very fine nylon, thinner than human hair.5 Up through the mid- 1960s the following passage from Duke Elder charac- terized the prevailing, generally conservative therapeutic approach to cataract extraction: "The operation should, as a rule, be attempted when the condition is bilateral and the vision after correction of the refractive error is poor (on an average below 6/18 or 20/60); for it is probable that an intact lens which is capable of some accommodative adjustment and through which a fair degree of vision is possible is more valuable than an aphakic eye."" that is, an eye without a lens.

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INTRAOCULAR LENSES AND VISUAL REHABILITATION Through the first half ofthe 20th century little attention was given to visual rehabilitation after cataract extraction. The aphakic condition, corrected by thick convex lenses, resulted in 25% image magnification, producing spatial disorientation and distortion, sensation of "everything swims about as if I were drunk," radical astigmatism, spherical and chromatic aberration (all of which create blurry images), and restricted visual fields with "startling" and "jack in the box" phenomenon.'7"8 In the latter situations, peripherally located objects suddenly appear or disappear and suddenly reappear again.'7 Figures 8-1 through 8-4 represent the work of John Sheets in depicting the qualitative and quantitative visual advantages of intraocular lens rehabilitation over aphakic or contact lens correction.'9 In the 1960s Robert C. Welsch, and, in a separate effort, David Volk claimed to overcome some of the nuisances of cataract glasses with altered lens designs. However, these never really met with any high degree of patient acceptance.5"7 Although contact lenses were somewhat popular in the 1970s and early 1980s, the difficulties with handling, hygiene, and corneal edema and ulceration in cases of extended wear and even daily wear limited their

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Fig. 8-1 through 8-4. Depicting the same landscape as seen with normal visual acuity, cataract glasses, contact lenses, and intraocular lenses. Note the magnification and distortion with cataract glasses and the striking similarity of the intraocular lens photograph to the normal one.'9 Reproduced by permission from Sheets, J.H.: Monograph on Cataract Extraction and Intraocular Lens. Odessa, TX, Sheets Eye Foundation, 1983.

Bull. N.Y. Acad. Med. CATARACT,-ATARACT SURGERYS~ -,JLsJIJRCFR A377I 377 use.2023 Thus, aphakic patients who may have achieved good surgical results after cataract surgery still had to contend with a series ofnew visual distortions and frustrations related to cataract glasses"8 or contact lenses.20 By the late 1970s, however, a new optical solution called pseudophakia was beginning to take root. Pseudophakia is achieved when an artificial intraocular lens is implanted into the eye. In primary intraocular lens cases, the cloudy, cataractous lens is removed first. Then, through the same incision, a lens made of clear plastic is implanted into the cleared lens capsule or "capsular bag." (See Figures 9-1 through 9-8 for a more detailed view of modem extracapsular cataract extraction and insertion of an intraocular lens performed by the author circa 1985.) The implant itself consists of an optic and a haptic. The optic is a clear, injection molded or lathe-cut lens of polymethylmethacrylate or of silicone ranging from about 6 to 7.5 mm in diameter, depending on the surgeon's preference (the smaller optics diameters are currently being investigated by surgeons who prefer smaller cataract incisions). The haptics are footpieces or hinges attached above and below the optic, molded together either in one piece polymethylmethacrylate to the optic or mechanically inserted one piece above and one below the optic of fine gauge polyprophylene. Thus, cataract surgery has become an exchange process. An aging or opacified human lens is replaced by a clear, synthetic lens. On many occasions the synthetic lens positions entirely in the capsular bag.

Fig. 9-1. Superblade superior corneal-scleral incision after conjunctival peritomy. Note brunescent cataract and poorly dilated pupil secondary to long-standing miotic therapy for glaucoma. Adhesions between the back of the iris and anterior lens capsule were cut with viscoelastic material, injected with a fine gauge needle.

Vol. 68, No. 3, July 1992 378 J. W. EICHENBAUMETCHENBAUM

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In certain instances, however, the upper haptic hinges at the front recess of the ciliary body. Recently, similar visual results were obtained at one year with haptic placement in the capsular bag or in front of the ciliary body.24 A number of innovative cataract surgeons through the 1970s and 1980s drastically improved the design and quality of the intraocular lens as well as

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Fig. 9-4 a and b. A brunescent lens nucleus is delivered with combination gentle counter pressure of a muscle hook below and lens loop above. the techniques of cataract extraction."5 In 1967 Charles Kelman developed a procedure to remove a cataract through a 3 mm incision26 called phacoemulsification. The procedure at that stage was highly touted in the lay press, but enjoyed limited acceptance among most ophthalmologists.8 The procedure awaited dramatic improvements in its own technology, intraocular lens design and quality, and the learning curve of a whole new generation of cataract surgeons. Along these lines Peter Choyce, in anterior chamber lens, Cornelius Binkhorst, in iris fixation lenses, and Steven Shearing, in posterior

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Fig. 9-5. Cortical remnants within the lens capsular bag are irrigated and aspirated out of the capsular bag after three 10-0 nylon corneal-scleral wound control sutures have been placed.

Fig. 9-6. The posterior chamber lens is grasped with a forceps, inspected, and irrigated with balanced salt solution and 0.2 cc of viscoelastic substance to facilitate insertion. chamber lenses made significant contributions.27 Charles Kelman, John Sheets, James Gills, Manus Kraff, Richard Kratz, William Simcoe, Robert Sinskey, and Norman Jaffe, among many others, removed many of the obstacles in the learning curve of extracapsular cataract surgery. Modem irrigation aspiration devices that allow selective removal of lens material, leaving behind a clear posterior capsule, as well as operating microscopes have armed current cataract surgeons with unprecedented surgical control.8

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+ i . ..vZ4 :.. Fig. 9-7a and b. The posterior chamber lens is inserted into the lens capsular bag, lower haptic first, then optic, and finally the superior haptic. Appropriate calculations were developed that enabled ophthalmologists to order the correct lens power for the patient.28-30 This correct lens power would, of course, depend on the distance at which the patient needed to spend most of his productive time. For example, a person who spent most of the time driving a motor vehicle would likely opt for sharpest distance correction. The ophthalmologist would then calculate based on that require- ment and would implant the appropriate lens power. If things went well, the person would then have to wear glasses only for reading. Also, patients with

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Fig. 9-8. The implant position is tested and not shown: viscoelastic substance is aspirated out of the anterior chamber; the corneal-scleral incision is sutured with additional reinforcing 10-0 nylon sutures; the inferotemporal subconjunctival space is injected with 10 mg of solumedrol and 15 mg ofgentamicin; the conjunctival flap is pulled down to cover the sutures. residual astigmatism, not compensated for in the optic of the implant, would wear glasses to correct that amount of astigmatism. Astigmatism is uneven refraction of incoming light rays usually generated from uneven corneal topography resulting in a blurred image. With time, wound remodeling occurs, and mild to moderate postoperative astigmatism is reduced, if not entirely cleared. In cases of severe residual astigmatism, several ophthalmic surgeons have devised surgical techniques to alter the shape of the wound or the cornea.3' Also in the early 1990s, perhaps with newer types of smaller incisions,32'33 farther from the cornea,34 and smaller foldable implants less astigmatism may be generated.32'33 Currently clinical trials are in progress with multifocal implant lens designs. By adding several gradients of power to the lens configuration, various focal lengths can be appreciated by the patient without necessarily putting on glasses, e.g., for reading. Problems, however, with depth of field, contrast sensitivity, simultaneous vision, blurry vision, and positioning of lens gradients will undoubtedly undergo further analysis.35 Pseudophakia, while solving most of the annoying optical problems of aphakic glasses or the contaminant issues of contact lenses, did not evolve without considerable biological and technical difficulties. From 1948, when Harold Ridley in England placed the first intraocular lens in a human eye, 1 the late 1970s, untold numbers ofpatients have suffered from intraocular

Bull. N.Y. Acad. Med. CATARACT SURGERY 383 lens complications. Problems of intraocular lens design, shape, material, lack of correct positioning, movement, decentraction, infections from contami- nation, bleeding, inflammation, glaucoma, and corneal edema were not uncommon. Recently, the clinicopathological findings in an eye after 32 years of successful anterior chamber lens implantation were described. In 1956 a rigid, totally polymethylmethacrylate Schreck anterior chamber lens had been implanted in the eye of a 28-year-old white man one year after traumatic cataract. For 30 years the postoperative course was unremarkable. However, in 1988 the patient developed severe glaucoma (increase in ocular pressure) because of scar tissue proliferation around the implant where it was secured via the footplate within the anterior chamber angle of the eye. Proliferation of corneal endothelial cells covered the fibrous membrane and anterior chamber angle structures. However, no inflammatory reaction and only very mild foreign body reaction were observed in the haptic region. (Figure 10) Thus, despite the fibrous membrane derived from the anterior chamber location, clinically and histopathologically polymethylmethacrylate remained sufficiently inert and biologically compatible in a human eye for over 30 years.36 Within the past 10 years the quality ofvision achieved after cataract surgery

Fig. 10. 32-year follow-up of rigid Schreck anterior chamber lens. Note white fibrous membrane over lens and angle structures (black circles). Reproduced by permission from Rumelt V. et al.: Fibrous membrane covering anterior chamber angle structures (dotted region), haptic and optic of intraocular lens stable in a human eye for over 30 years. Arch. Ophthalmol: 108, 401-04, 1990, and Stark, W. S., Somer, A., and Smith, R. E.: Changing trends in intraocular lens implantation. Arch. OphthalmoL. 107: 1441-44, 1989.

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6-Month In-e4al Fig. I1. Reproduced bv permission from Stark W.S., Somer. A.. and Smith. R.E.: Changing trends in intraocular lens implantation. Arch/. OplAtalmol. 107. 144 1-44. 1989.

with lens implantation has been so dramatically improved that there has been a marked increase in patients undergoing the procedure. Cataract surgery now accounts for 12% of the entire Medicare budget and is the most frequently performed surgical procedure reimbursed by Medicare. During the past decade the number of cataract operations has increased more than two- fold. Some have predicted that intraocular lens implantations will approach 2 million per year. Federal regulators see cataract surgery as an increasing problem in health care budget control.37 Although the Health Care Finance Administration has tried to contain costs of cataract surgery by reducing reimbursement, these measures have failed. According to a recent survey conducted by Stark et al. the annual number of procedures for other epidemiologic reasons may have already peaked and may even have begun to decline. (Figure I 1) The rapid rise from 1983 to 1987 in intraocular lens procedures stems from increasing acceptance by ophthalmologists and the population at large that the greatly improved rehabilitation of vision they provide justified a change in the indications of cataract surgery.3 According to the American Academy of Ophthalmology Preferred Practice Pattern pamphlet on cataract surgery, the indications for surgery are now considered for various levels of impairment. When visual disability with Snellen acuity is worse than 20/50 and subjective, objective, and educational criteria are met, cataract surgery may be indicated. These criteria include: the patient's subjective vocational or avocational needs; objective criteria that include no other limiting visual or health-related problems; and, most impor- tant, a thorough educational review of the risks versus the benefits of cataract extraction with lens implantation in each case. Thus, a patient no longer has

Bull. N.Y. Acad. Med. CATARACT SURGERY 385 to await ripening of the cataract. Interference with life style or with function at work or at leisure have become sufficient grounds to remove a cataract.' On the other hand, many patients with cataracts in their middle and later years subjectively experience little or no visual difficulty. Many have learned to cope with adequate monocular vision or only somewhat reduced visual acuity. In these cases the patients function quite satisfactorily. They should not be urged to undergo cataract surgery merely because the cataract is there or the procedure has become technologically easier to perform.

CURRENT PATTERNS OF PRACTICE IN CATARACT SURGERY In the latter 1960s Charles Kelman introduced phacoemulsification (or simply "phaco" as it is known today). Through a small (approximately 3.5 mm) incision using extracapsular technique, the lens nucleus and cortex are extracted. Although the incision has to be enlarged to accommodate a conventional implant's entry, the incision is closed by fewer sutures or in some types of incisions without any suture. Postoperative morbidity and recuperation time is shortened because a smaller incision heals faster. Hos- pitalization as well was initially reduced and then converted to the ambula- PREFERRED TYPE OF ECCE SURGERY 1985-1989 loo% , 89-

Planned ECCE Phacoemulsification Surgical Preference * 1985 21986 ~1987 :j1988 Ej1s89 Fig. 12. Reproduced by permission from Learning, D. V. Preferred type ofECCE surgery 1985- 1989. Ophthalmol. Times 15: 10, 1990.

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tory, outpatient category, using local anesthesia. Kelman originally devised a combination probe that fragmented the cataract by ultrasonic vibrations and then aspirated the fragments from the anterior chamber. Initial difficulties in early methodology of cataract fragmentation, corneal decompensation, and capsule preservation all presented a challenging learning curve that underwent and is still undergoing progressive improvements in machinery and technique. Nonetheless, although only 2 to 11% of cataract surgeons utilized phaco by 1985, lately the numbers seem to be increasing. (See Figure 12, preferred type of extracapsular surgery (ECCE) 1985-1989.) The same survey showed an increasing parallel trend toward local anesthesia (Figure 13) and a recent tendency toward smaller implant optic diameter. (Figure 14)38 However, by the mid 1980s 75% of all cataracts were removed extracap- sularly and had intraocular lens implants. The percentage of cataract patients receiving intraocular lens today exceeds 90%. During the past 15 years technological advances, particularly in intraocular lens implants, have re- shaped the lives of postoperative cataract patients. Instead of barrel-shaped distortion of images with 25% magnification, visual field contraction with "jack in the box" image pop up and sundry difficulties with eye-hand

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10-

6mm 6.5 mm 7 mm 9 mm OTHER Optic Diameter *1988 LZ1989 Fig. 14. Reproduced by permission from Learning, D.V.: Trends in size of optic diameters of intraocular lenses in cataract surgery. Ophthalmol Times 15: 10, 1990. coordination prevalent with cataract glasses after several weeks the quality and quantity of vision can often be restored to near precataract dimensions by intraocular lenses. Food and Drug Administration data showed that in a sample of more than 50,000 patients one year following cataract surgery with lens implants, visual acuity was 20/40 or better in about 85%. Ifpre-existing pathologic conditions such as amblyopia, macular degeneration, glaucoma, and corneal dystrophy are excluded, then 90-93% ofthe eyes achieved 20/40 or better visual acuity. Given that these results represent a large number of eye surgeons who used 37 different types oflenses, including iris fixation and anterior chamber lenses that have since fallen into lesser consideration, as well as posterior chamber lenses (the current intraocular lenses of choice), modem methods of cataract surgery as a discipline have achieved exemplary results. Reports of surgeons using only posterior chamber lenses now show even higher success rates in uncomplicated cases. ' Despite the sentinel improvements in cataract surgery over the last 15 years, vision-threatening complications are still fairly common. Retinal de- tachment may occur in as many as 3%. Persistent cystoid macular edema

Vol. 68, No. 3, July 1992 388 J. W. EICHENBAUM occurs in anterior chamber and iris fixation lenses in approximately 3% and about 1% in posterior chamber lenses. Short-term cystoid macular edema is seen in about 15% of current cataract surgery patients. Corneal edema is uncommon with current posterior chamber implants but frequently seen as a later complication of iris fixation and anterior chamber implants. This late complication is the major cause for corneal transplantation during the last five years.' As many as 40% ofextracapsular cataract surgical patients have to undergo YAG laser capsulectomy because of posterior lens capsule opacification. The patient experiences recurrent cloudiness in vision known as secondary cataract. Contrary to lay understanding, only the secondary cataracts at this writing are treated by laser. As an outpatient, in literally billionths ofa second with thousandths of a joule of vaporizing energy, the secondary cataract is eliminated. While retinal detachments and glaucoma have been reported after YAG laser capsulectomy, they are not common. Other less common but equally compelling problems after cataract surgery include uveitis, glaucoma, hyphema, lens dislocation, endophthalmitis, and expulsive choroidal hemorrhage. Although the overall prognosis for good visual acuity is excellent, the element of surgical risk with sight-threatening drawbacks still has to be considered. REFERENCES

1. American Academy of Ophthalmology, Quality of Care Committee: Cataract in the Other- wise Healthy Adult Eye. San Francisco, American Academy of Ophthalmology, 1989. 2. Liesegang T.J.: Cataract and cataract operations. Mayo Clin. Proc. 59: 556-57, 1984. 3. NIH Publication No. 87-2755. 4. Ophthalmol. Man. March 1, 1989. 5. Gorin G.: History ofOphthalmology. New York, Raven, 1985, p. 6. 6. Chance B.: Ophthalmology. New York, Hafner, 1962, pp. 28-29. 7. The Human Eye in Anatomical Transparencies, Kronfeld, P.C., McHugh, G., Polyak, S. L., editors. Rochester, NY, Bausch and Lomb, 1943, pp. 73-92. 8. Terry, A.C., Stark, W.J., and Maumenee, A.E.: History and Trends in Cataract Surgery and Intraocular Lenses in Anterior Segment Surgery, Stark, W.J., Terry, A.T., and Maumenee, A.E., editors. Baltimore, Williams and Wilkins, 1987, pp. 1-4. 9. Duke, E.S.: System ofOphthalmology, vol XI: Diseases ofthe Lens and Vitreous; Glaucoma and Hypotony. St. Louis, Mosby, 1969, p. 257. 10. Nuland, S.B.: Doctors, the Biography ofMedicine. New York, Knopf, 1988, p. 395. 11. Duke-Elder, S.: Text-Book ofOphthalmology, vol. II. St. Louis, Mosby, 1938, p. 1374. 12. Morgan, K.S.: Congenital and infantile cataracts. Current Op. Ophthalmol. 1: 8-14, 1990. 13. Kirby, K.D.: Advanced Surgery ofCataract. Philadelphia, Lippincott, 1955, pp. 115-94. 14. Skorkin L. Jr.: Optom. Times: May 18, 1989. 15. Personal communication. Morris Feldstein, 1984. 16. Personal communication. Jerome Levy. Capsulorhexis was re-utilized more recently by Dr. Calvin K. Fercho, Dr. Howard Gimbel (ofCanada), Dr. Jerome Levy, and others endeavoring

Bull. N.Y. Acad. Med. CATARACT SURGERY 389 to facilitate extracapsular cataract extraction as well as "in the bag" intraocular lens placement. 17. Dabezies, O.H.: Defects of Vision through Spectacle Lenses Used in the Correction of Aphakia. In: Alternatives to Intraocular Lenses in Anterior Segmental Surgery, Stark, W.J. et al., editors. Baltimore, Williams and Wilkins, 1987, pp. 197-216. 18. Woods, A.C.: The adjustment to aphakia. Am. J. Ophthalmol. 35: 118-22, 1952. 19. Sheets, J.H.: Cataract Extraction and Intraocular Lens. Odessa, TX, Sheets Eye Foundation, 1983. 20. Eager, A.E., Stark, W.J., Martin, H., et al.: Extended Wear Contact Lenses for Patients with Aphakia and Myopia: The Long Term Experience at the Wilmer Institute in Anterior Segment Surgery. In: Surgery ofthe Anterior Segment, Stark, W.J. et al., editors. Baltimore, Williams and Wilkins, 1987, pp. 217-21. 21. Eichenbaum, J.W., Feldstein, M., and Podos, S.M.: Extended wear aphakic soft contact lenses and corneal ulcers. Br. J. Ophthalmol. 66: 663-66, 1982. 22. Lemp, M.A., Blackman, H.J., Wilson, L.A., and Leveille, A.S.: Gram-negative corneal ulcers in elderly aphakic eyes with extended-wear lenses. Ophthalmology 91: 60-63, 1984. 23. Nirankari, V.S. and Baer, J.C.: Persistent corneal edema in aphakic eyes from daily-wear and extended-wear contact lenses. Am. J. Ophthalmol. 98: 329-35, 1984. 24. Knopf, H.: Visual results similar with IOL placed in the bag or sulcus. Ophthalmol. Times 15(23): December 1990. 25. Drews, R.C.: Two Million Intraocular Lenses: The Failures and the Future in Anterior Segment Surgery, Tark, W.J. et al., editor. Baltimore, Williams and Wilkins, 1987. 26. Kelman, C.D.: Phacoemulsification and aspiration. Am. J. Ophthalmol. 64: 23-35, 1967. 27. Deutman, A.F.: History of Lens Implantation and Current Trends in Europe in Anterior Segment Surgery. Stark, W.J. et al., editors. Baltimore, Williams and Wilkins, 1987, pp. 5- 13. 28. Binkhorst, R.D.: Intraocular lens power calculations. Int. Ophthalmol. Clin. 18: 237-52, 1978. 29. Thompson, J.T.: Intraocular Lens Power Calculations; Critical Evaluation of Different Techniques in Anterior Segment Surgery, Stark, W.J. et al., editors. Baltimore, Williams and Wilkins, 1987, pp. 31-36. 30. Sanders, D.R.: Intraocular Lens Power Calculations; Techniques and Results in Anterior Segment Surgery, Stark, W.J. et al., editors. Baltimore, Williams and Wilkins, 1987, pp. 37- 47. 31. Rowsey, J.J.: Cataract Astigmatism: Causes and Corrections in Anterior Segment Surgery, Stark, W.J. et al., editors. Baltimore, Williams and Wilkins, pp. 330, 38. 32. McFarlan, M.S.: Sutureless phacoemulsification. MVP Video J. Ophthalmol. 6(4): August 1990. 33. Post, C.T.: 4" x 4" No Stitch surgery. MVP Video J. Ophthalmol. 6(5): October 1990. 34. Pannu, J.S.: No patch, one stitch phaco. MVP Video J. Opthalmol. 6(5): October 1990. 35. Nordan, L.T.: The aspheric multifocal implant. MVP Video J. Ophthalmol. 6(4): August 1990. 36. Rummelt, V., Lang, G.K., Yanoff, M., and Naumann, G.O.H.: A 32-year follow up of the rigid Schreck anterior chamber lens; a clinicopathological correlation. Arch. Ophthalmol. 108:401-04, 1990. 37. Stark, W.S., Somer, A., and Smith, R.E.: Changing trends in intraocular lens implantation. Arch. Ophthalmol. 107: 1441-44, 1989. 38. Leaming, D.V.: Amer. Society ofCataract and Refractive Surgery's Symposium on Cataract, IOL, and Refractive Surgery. Ophthalmol, Times 15(6): 1, 10, 1990.

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