Many years ago while serving as a general medical officer at the National Leprosarium ( Carville ), I was privileged to work with Dr. Margaret Brand, a British ophthalmologist, who had spent over 25 years as an ophthalmologist serving leprosy patients in southern India. At that time she probably knew more about clinical leprosy and the eye than anyone in the world. I chose ophthalmology mainly due to Margaret Brand, my mentor.
Margaret once told me she had saved many eyes in India by using a Gundersen flap. With a truly bad cornea — marked diffuse abscess ( ? fungal, ? herpes, ? bullous ), a large indolent chronic ulcer, descemetocele, etc., a Gundersen conjunctival flap can often save the eye. Furthermore, if you have a phthisical eye, first doing a Gundersen flap might allow you later to fit an overlying prosthesis. Trygve Gundersen MD first described this new conjunctival flap in 1958.
First do a peribulbar( anesthetic ) injection, then a subconjunctival injection superiorly ( lidocaine 1% or 2% with epinephrine 100,000 – 200,000 ). Blow up the superior bulbar conjunctiva but do not pierce the conjunctiva in the areas to be used for the flap. Next gently remove the entire corneal epithelium either with a # 15 blade or a sterile cotton applicator ( Q tip ) wet with BSS, or a topical antibiotic, or 5% povodine – iodine (Betadine) or diluted rubbing ( isopropyl ) alcohol. Do not disturb limbal stem cell areas. Debride necrotic tissue. Many surgeons utilize an inferior intracorneal traction suture if necessary.
You want to bring down only the bulbar conjunctiva — either excise or leave behind Tenon’s capsule. Undermining, freeing up the conjunctiva takes time if done correctly. Avoid buttonholes. You need a loose large thin mobile superior conjunctival flap. Do not drag down Tenon’s fascia as that will result later in retraction of the flap. You do not want any tension/traction on the flap. If you can not easily get the conjunctival flap down to the inferior limbus then make an inferior peritomy, undermine, and bring up the lower bulbar conjunctiva to cover the inferior 2 – 3 mm of the cornea. You can also do a 360-degree peritomy with relaxing incisions.
I like 10-0 nylon sutures either interrupted, running or both. Some surgeons prefer larger absorbable sutures at both superior and inferior limbal areas. In the end, dilate the pupil and cover with an antibiotic ointment. Leaving a pressure patch on for 48 hours reduces post-op chemosis.
Most experienced corneal specialists that I have questioned, would do a Gundersen flap over a descemetocele. Obviously, you are less likely to appreciate a corneal perforation and / or a flat A.C. with a Gundersen flap covering the cornea. Stored glycerol cornea suitable for a patch graft is sometimes available. The Alabama Eye Bank <[email protected]> has free sterile glycerol corneas available in limited amounts for the developing world ( patch graft only ). Some centers use sclera as the patch graft material.
Gundersen conjunctival flaps are now used infrequently where a therapeutic penetrating keratoplasty is an option. However, I would strongly recommend this procedure. As noted by Dr. Brand you can save many eyes and avoid an evisceration. If the patient still has light perception vision and can still see the color red ( color perception ), they may well be a candidate for a Gundersen flap.
Peace,
Baxter McLendon