4) A fine wire, .202 mm diameter spatula needle is ideal. (Nonabsorbable sutures for Faden use a heavy needle favored by retinal surgeons. These heavier needles require great care in their use.)

All of the above said, inadvertent perforation of the retina does occur occasionally even in the most experienced hands. This can be due either to a "slip" or to unusually thin sclera - Be careful!

Some investigators have estimated retinal perforation occurrence to be as high as 10% - this seems a little high. However, if the incidence even approaches 10%, it speaks for the benignity of the condition - suggesting that vigorous attempts at treatment should be avoided!!

What should be done if a "too deep suture" or scleral perforation is suspected?

1. Continue with the suture pass and tie the suture as you would ordinarily.

2. Put dilating drops in right away so that the pupil will be dilated at conclusion of the procedure. - Go ahead, finish the operation.

3. Before examining the retina, check the intraocular pressure if you suspect the eye is soft from loss of vitreous. In older patients, liquified vitreous can escape through a tiny perforation causing a very soft eye.

4. Examine the area of the retina around the site of the needle passage. Make a note of the event in the operative report. The usual evidence of perforation is a "dot" hemorrhage at the site of needle passage.

5. In an adult with loss of vitreous and a soft eye, place a tight patch over the eye and tell the family that some of the liquid from the center of the eye "leaked" and that you would like to examine the patient the next day. Contact a retina consultant for advice (or more accurately to check in). The retina specialist may want to see the patient in a few days. A common response is, "I make holes in the retina that way lots of times and nothing bad happens - don't worry."

6. Do not under any circumstances apply cryo treatment transsclerally. This may cause vitreous reaction causing a retinal detachment. In cases of retinal perforation, NO TREATMENT is the best course to follow. Simply observe. Experimental study of retinal perforation in rabbits by Sprunger showed that ringing the perforation with diode laser walled off the hole effectively with minimal reaction. Cryo caused much more reaction and has been known to lead to retinal detachment in some cases. However, NO TREATMENT is the best and safest course.

7. Several weeks after a retinal perforation occurs, a white scar will be seen.

8. Serious complications of retinal perforation, including phthisis leading to enucleation, are more likely to occur after incautious - heavy cryo therapy applied over the site at the time of surgery. A harried strabismus surgeon responding in panic instead of with reason can cause a complication which need not have occurred.

Vitritis has occurred from collagen suture in the vitreous. It is not known if a similar reaction results from synthetic absorbable suture.

It is not uncommon to see areas of heavy retinal pigment dispersion and scarring in the retinal periphery of adult patients who had strabismus surgery as a child. This is evidence of scleral perforation. These are incidental findings and have no clinical significance.

The important thing to remember when placing a suture in sclera to reattach an extraocular muscle is: LESS IS MORE!