•Pick up the iris close to the edge where it was torn, and then exit through the sclera about 1.5 mm from the limbus.

–A scleral bed up half thickness may be first prepared here so that the knot can be covered.9

–The needle may not be long enough to reach all the way; the sclera where the needle exits should be indented by the nurse so that the surgeon can grab the needle and pull it out.

–Repeat the same thing with the other needle. The “moment of truth” is when the suture loop reaches the paracentesis: if either needle accidentally went through corneal tissue, the suture will be stuck here and must be discarded only for the entire procedure to be repeated.

•Tie the knot, trim the suture (turn it inside if it fits the intrascleral channel), and close the conjunctiva.

Depending on the size of the lesion, multiple sutures may be necessary.

An alternative technique is to open the sclera over the lesion and suture the iris directly. Obviously, this technique has higher morbidity.

48.2.3 Permanent Mydriasis

The surgeon has two options. A few sutures as described above (Sect. 48.2.1) at two, opposite locations may constrict the pupil, but it will not be round (see Fig. 48.1d.). A more elegant, but technically very difficult, technique is the purse-string or iris cerclage suture (see Fig. 48.6).

•Create four paracenteses (at 3, 6, 9, and 12 h).

•Carefully enter one of these, wiggling the needle as described above (Sect. 48.2.2), and pick up the iris by weaving in-and-out of it, at two to four locations in the quadrant adjacent to this paracentesis (you can start in either direction). A vitrectomy forceps can be held in your nondominant hand to gently pull up the iris or guide the needle’s path.

•Exit the AC at the paracentesis at the far end of the quadrant.

–Insert a 27 g needle through the paracentesis and bring out the needle so that its tip is buried inside the bore of the 27 g needle, again to avoid penetrating into corneal tissue with the suture-needle.

•Repeat the procedure in all four quadrants.

•Tie and trim the suture as described above.

9 I stopped doing this.