double-armed straight STC-6 needle polypropylene suture

External Transscleral Posterior Chamber Lens Fixation

one

To the Editor.\p=m-\Iam involved in a resident teaching program and I am acutely aware of the difficulties encountered by trainees passing the needle from the limbus under the iris and through a previously prepared scleral bed. Shapiro and Leen's1 method of passing the needle in the opposite direction is excellent. This approach also has a disadvantage. The learning surgeon has difficulty tying the suture to the haptic of the intraocular lens. This difficulty is compounded in the authors' approach, for the surgeon now has only one end of the suture available to manipulate. This adds considerably to the time that the globe is open during the operation. One solution would be initially to limit the size of the opening at the 12 o'clock position to 1 to 2 mm. After the haptics are tied, the incision could be increased in size. The authors used a separate polypropylene (Prolene) suture tied first to itself and later to the polypropylene suture attached to the intraocular lens. This rather awkward step could be eliminated if they used Ethicon 90990 10-0 Prolene suture (Ethicon, Somerville, NJ). This suture has modified McCannel suture on one end and a small curved spatula nee¬ dle on the other. Miles H. Friedlander, MD New Orleans, La

extending

The author does not have any ods mentioned in this letter. 1.

proprietary interest in the materials or the meth-

Shapiro A, Leen MM. External transscleral posterior chamber lens fixOphthalmol. 1991;109:1759-1760.

ation. Arch

Reply.\p=m-\We appreciate Dr Friedlander's interesting and practical suggestions. In procedures described in our article and elsewhere1 for external transscleral posterior chamber lens fixation, tying a 10-0 polypropylene suture to the lens haptic may indeed be a difficult maneuver for several reasons. As the polypropylene suture is tied to the lens haptic, the knot may easily slip off the haptic. We have found that a lens recently released by Alcon (Model CZ70BD, Fort Worth, Tex) has holes positioned within the haptics at an optimal site for suture lens fixation, and avoids the problem of knot slippage. The residents in our teaching program have found this lens much easier to use. This lens is also 12.5 mm in length, an ideal length for sulcus placement. As pointed out by Dr Friedlander, tying a one-ended suture may also be challenging. Our technique describes the use of a double-armed polypropylene suture that extends externally between the two scleral flaps, both ends emerging out of the eye through In

the corneoscleral incision. Because this suture is continuous, the ends can be pulled out maximally through the corneo¬ scleral incision to facilitate tying each one-ended suture to the haptic without the risk of inadvertently pulling the suture out of the sulcus. Polypropylene suture is also difficult to manip¬ ulate. A good assistant who can stabilize the lens during ty¬ ing is helpful in minimizing the time spent with the globe open. Placing the optic on a generous drop of viscoelastic during tying also helps to immobilize the lens. Limiting the size of the initial incision to 1 to 2 mm in length is unfortunately not an option in our procedure since the in¬ cision should be large enough to accommodate the 5-mm width of the lens glide. The use of two separate Ethicon 90990 10-0 polypropylene sutures (Somerville, NJ) with each straight arm passed through one of the two flap beds may simplify subsequent fix¬ ation of the transscleral suture in the flap bed with the second curved arm. In our procedure, however, we have chosen to use

(Ethicon) to provide the safety feature of a continuous suture

from one scierai bed to the second as described above. A separate single-armed 10-0 polypropylene suture on a curved spatula needle is later used to fix the transscleral su¬ tures to the scierai bed after the posterior chamber lens is in place. Although the Ethicon 90990 10-0 polypropylene suture is an option, the benefit of our safety feature to prevent inad¬ vertent slippage of the suture out ofthe sulcus during the tying of the knot on the haptic would be compromised. Martha M. Leen, MD Amiram Shapiro, MD Philadelphia, Pa The authors have described.

no

proprietary

interest in

1. Lewis J. Ab externo sulcus fixation.

Alcon, Ethicon,

or

the methods

Ophthalmic Surg. 1991;22:692-695.

The Use of Animals in Medical Education To the Editor.\p=m-\Thearticle by Foreman1 in the March 1992 issue of the Archives is yet another manifestation of the American Medical Association's (AMA) ongoing propaganda campaign to defend animal experimentation, as outlined in its 1989 "Action Plan."2 Publications of the AMA have been replete with commentaries and essays that uncritically endorse the animal experimentation status quo and attack the animal rights movement, while failing to address scientific objections to animal research. The fact that most physicians appear to favor the use of animals in medical education is hardly surprising. Most of them, after all, were trained in a system that traditionally encourages such use. Asking those who use animals whether it is ethically acceptable to do so is like asking slave owners if slavery is ethically acceptable. The answer is quite predictable. According to the AMA's Council on Scientific Affairs, the use of animals in medical education is "essential." Today, however, approximately one fourth of American medical schools do not include the use of animals in their curricula.3 Further, at nearly all schools that do include exercises on an¬ imals, the exercises are optional.4 If the AMA truly consid¬ ered the use of animals essential, it would be ethically com¬ pelled to censure such outstanding medical schools as George Washington and Yale Universities. In support of the contention that the use of animals is nec¬ essary in medical education, Foreman mentions the importance of students' experience with "living animals" and whole biolog¬ ical systems. Students gain such experience, however, every time they practice routine medical procedures on one another, examine a patient, or, under careful supervision, treat a patient. Surely the clinical practice obtained in externships is the best alternative to animal use, but this alternative is not mentioned. Although animal rights have nothing to do with the neces¬ sity for the use of animals in medical education, Foreman's piece—typical of AMA publications on animal exper¬ imentation—links opposition to the use of animals with the illegal activities of a minority of animal rights activists. By resorting to such ad hominem ploys, Foreman avoids dealing with legitimate concerns about subjecting innocent and help¬ less animals to stressful laboratory conditions and painful procedures. The AMA's survey reports 3800 incidents of ha¬ rassment attributable to animal rights activists. Does ha¬ rassment include peaceful protest? The question is well worth asking, since the reported costs of animal rights activism to medical schools include costs related to demonstrations. Is the AMA suggesting that citizens do not have the right to

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External transscleral posterior chamber lens fixation.

double-armed straight STC-6 needle polypropylene suture External Transscleral Posterior Chamber Lens Fixation one To the Editor.\p=m-\Iam involved...
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