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For generations, ophthalmic surgeons have worked toward perfecting the intracapsular extraction of cataracts. Yet, on occasion, even the most experienced and dexterous of surgeons unavoidably ruptures the capsule. Cryoextraction, in contrast to extraction by means of erisophake or forceps, by placing the tractive stress not on the fragile capsule but on the whole lens invariably assures a successful intracapsular operation. It is rather surprising that cryoextraction has found little acceptance in this country since Krwawicz first reported his technique in 1961. 1,2 Perhaps this has been due to a lack of completely satisfactory instrumentation. Krwawicz merely immersed a metal probe into a mixture of alcohol and solid carbon dioxide, lowering the temperature effectively but for a relatively short period that made rapid surgery (or repeated immersions and applications) necessary. Other instruments that are now available are the liquid nitrogen unit originally developed for brain surgery (involving a massive monitoring unit)

During the last few decades, phacoerisis has achieved increasing popularity as a method of delivering the cataractous lens from the eye. The early work of Stoewer, 1 Hulen, 2 and Barraquer 3,4 laid a firm foundation for the many modifications of the suction cup and apparatus that were to come. An excellent suction cup was constructed by Dimitry 5 in 1939, after considerable inquiry into the physical aspects of vacuum production in phacoerisis. Floyd and Grant, 6 in 1946, used the Dimitry tip in conjunction with a small spring-operated syringe. The vacuum could be established easily and accurately, and this device was a great improvement over existing instruments. Bell, 7 in 1948, introduced a new tip attached to a rubber bulb which provided fingertip control and comparatively easy manipulation. The indefinite vacuum level and excessive flexibility exhibited by this instrument have proved a disadvantage in some instances. Thomas 8 considered

Summaries PART I (Dr. Barraquer) The use of alpha chymotrypsin in cataract surgery requires a number of changes in the operative technique. Complications occurring during the operation and in the immediate postoperative course are most likely due to a surgical technique which has not been adequately adapted to the altered conditions. When injecting the alpha chymotrypsin, the cannula must never touch the pigmentary layer of the iris. Forward dislocation of the lens reduces the space available for introduction of an erisophake or capsule forceps, which may damage the corneal endothelium. Tumbling of the lens may damage the hyaloid. The complication of late loss of the anterior chamber following the use of alpha chymotrypsin seems to be caused by a slight delay in wound healing in combination with the usual decrease in the rate of formation of aqueous humor following cataract surgery. This complication may be reduced to a minimum by (1) placing the incision one mm. from the limbus beneath a limbal-based conjunctival flap, (2) perfect hemostasis, (3) removal of the enzyme from the eye as early as possible, (4) perfect wound apposition by means of corneoscleral radial sutures and (5) a method of limited zonulolysis (Hill). PART II (Dr. Hill) The application of two drops of a 1:5,000 solution of alpha chymotrypsin to the region of the zonules at the 6-o'clock position in selected cases appeared to facilitate lens delivery by tumbling. This technique would seem to avoid or reduce the likelihood of some of the complications which have been associated with the use of total zonulolysis in the older age group. It is felt that poor wound healing with the use of alpha chymotrypsin is either due to the type of incision or to the method of wound closure rather than to the enzyme itself. Postplaced sutures are more likely to result in leaky wounds than sutures carefully preplaced in a groove on the firm unopened eyeball. 33 College Avenue. Barraquer Institute.

The delivery of the crystalline lens by the use of suction, termed phako erisis by Barraquer, 1 has enjoyed a period of popularity over the past 50 years. His original description in 1916 incorporated a motor driven pump connected to an erisophake by a rubber tube. This was modified by Dimitry 2 in 1939 who advocated the use of a simplified sucking-disc instrument. It used less suction and, therefore, limited the hazard of extreme suction on the vitreous and iris, as well as on the lens capsule itself. In 1948, Bell 3 devised a surgical instrument which consisted of a small rubber contact glass sucker and a Dimitri tip. In 1951, Harrington 4 further modified Bell's erisophake by using a solid handle rigidly fastened to the needle holding the suction cup. This eliminated the chance of pressure on the rubber ball and the loss of suction on the lens

A new method is described for extracting intumescent cataracts by means of a pencilshaped metal instrument called the cryoextractor. The small, rounded, copper tip of the instrument is so refrigerated that when it is applied to the exposed lens superi¬ orly, the capsule and underlying cortex freeze and adhere to the cryoextractor. The lens is then removed by the sliding tech¬ nique. Contact with adjacent tissues should be avoided.9 A technique for removal of the posteriorly dislocated lens is described. A needle is passed through the sclera 5 or 6 mm. behind the limbus temporally. It is then passed behind the lens to the level of the nasal pupillary margin, where it is used as a lever, the lens being forced into the anterior cham¬ ber and against the cornea. The needle is introduced through the limbus nasally to hold the lens in place, and a combined ex¬ traction is performed in the usual manner, following which the needle is withdrawn.17 A study of 561 cases of cataract extrac¬ tion comparing the results of forceps extrac¬ tion with suction extraction by means of the Bell erisophake indicates comparable results by both methods. In intumescent cataract

This report describes retained intraocular metallic foreign bodies found in seven eyes after cataract extraction at the Illinois Eye and Ear Infirmary. The first case was seen in October, 1953, when a golden-colored, metallic-like foreign body was noted deep in the healed corneal wound of a patient who had had cataract surgery one month previously. The following month a similar foreign body was noted lying on the iris in another eye that had persistent, unexplained iritis following an uncomplicated lens extraction. In the following months five additional eyes which had recently been operated on were found to contain similar foreign bodies. In every case a gold-plated Bell erisophake had been used during the operation. These findings stimulated an investigation of our instruments, which revealed that every gold-plated erisophake used at this institution had a roughened surface, as seen on examination with the naked eye. On examination under high magnification

The simplification of instruments for intracapsular cataract extraction by the suction method has increased the popularity of the* procedure which Barraquer called "phakoerisis," and has reduced its hazards to such an extent that it may now be considered a safe method of cataract extraction in aver­ age hands. It is important, therefore, to know the manner in which the erisophake accomplishes the rupture or peeling of the zonular lamella from the lens and, after dislocation of the lens, allows its intracapsular extraction. In a previous publication concerned with "The mechanics of intracapsular cataract extraction" by the method of external pres­ sure and forceps traction, I stated that "the mechanism of action of the erisophake is based on an entirely different basic principle and is deserving of a special study already begun." Studies on animal and cadaver eyes and careful analysis by highly magnified slow motion pictures of erisophake extractions on living human eyes, plus microscopic and photographic studies on extracted lenses, have demonstrated a dynamic principle in phakoerisis which is wholly dissimilar from the mechanics of zonular rupture, lens dis­ location, and intracapsular lens extraction by the method of combined external pressure and forceps traction. The modern sucking disk exerts a safe, self-controlled, powerful, and evenly dis­ tributed pull on the anterior lens capsule and

From the seemingly infinite variety of techniques employed in cataract surgery, Dr. Havener has chosen to present in this book those techniques he finds most useful. A combined descriptive and pictorial format is used to show each step of the surgery. Discussions are very complete and meticulously precise. The illustrations by Sallie Gloeckner are superb, combining half-tone realistic drawings of the surgeon's view of the eye with graphic cross-sectional drawings of the same procedures. Every basic aspect of cataract surgery is covered beginning with premedication, cleaning and draping the eye, and local anesthesia. Readers will seldom find such a detailed description of these important, but often underplayed, preliminary steps. The operative procedures described include conjunctival flaps, corneoscleral incisions by several methods, details of suture placement, iridectomy, and use of alpha-chymotrypsin. Lens extraction is presented by methods of cryoextraction, erisophake, and forceps delivery. Although several alternative procedures are mentioned, Dr. Havener