I’ve been trying to get used to using loupes this month, and it’s a catch-22.
Loupes are magnifying glasses used in vascular surgery and other delicate operations. Imagine a jeweler’s magnifier, but for both eyes, fixed onto a regular pair of glasses, designed to focus on objects 18-22 inches away from your face. If you usually use glasses, the regular glasses can be prescription strength; otherwise, plain glass. I forget the exact magnification, but it makes plain the front and back walls of vessels which would otherwise be hard to see; nerves jump out as different in texture from the surrounding tissue; 7-0 prolene suture, otherwise invisible, looks quite solid. They’re made individually, and cost an incredible amount of money; the only way I could afford them was by using the educational allowance.
The trick is that you can only see an area about 6 inches in diameter at this magnification. Everything outside that range is invisible. You can tilt your head, as though using bifocals, to look over the magnification, through the regular glasses part, but then you’re disoriented as to where things are compared to what you were seeing in magnification. The effort of focusing at such high magnification makes you feel a little seasick after a few minutes, let alone if you make the mistake of switching too often between the two views. (Which is why the techs have to hand instruments right into your hand; it’s really impossible to keep working if you have to look up to find the sutures and the instruments.)
Hand movements are difficult, too. I hadn’t realized what a component visual feedback is in the handiwork of surgery. I still have to be able to see at least part of the suture in order to tie correctly. I have to be able to see the needle to load it on the needle-driver. In the magnified field, it takes less force to move anything; your hand has less space to cross to get anywhere, so even a simple movement like suctioning is dangerous, since if you miscalculate the force to use, you could damage the blood vessel. And if suctioning is suddenly so complex, knot-tying is hopeless. I look like a complete klutz, just when I had finally progressed to the point of tying fairly easily, when not blinded by loupes.
Plus, the things are heavy, and to keep them from falling off your face into the sterile field, you have to tie them onto your head so tightly that I start to get a headache within minutes. By the end of the case, I’m so irritated I nearly trip over the cords and the nurses in my eagerness to get them off my head.
Most of the attendings and chief residents wear them for all but the most minor cases, because they do show tissue planes and small vessels with amazing clarity. Now that I’m using them, I can see how the seniors are able to dissect between structures where, with plain glasses, I could hardly perceive that there were two separate structures. Now, by the end of my second year, the attendings are asking questions if I’m not wearing them; they can tell if I can’t see the details they can.
It’s quite clear that I’m not going to be a vascular surgeon at this rate; but I still need to learn how to use the loupes, and how to do some vascular surgery. But it’s a catch-22: if I don’t operate with the loupes, I’ll never get any better; but I’m so hopelessly uncoordinated with them on that I can’t even pretend that it’s a good idea for the patient or the attending to have me around. (I have tried practicing on my embroidery at home, but that’s so flat, and the pieces so large compared to blood vessels, that it doesn’t seem to help.) I guess the only solution is to wear them for every single case I get into, vascular or not, whether they seem necessary or not, till I get more comfortable with them.