My Corneal Save was an exciting one that came to me with a unique history:
An elderly woman was referred to me following a history of corneal dehiscence following a peribulbar block! The area of dehiscence was about 3 mm in the inferior quadrant. The surgeon had quickly put in some sutures and also excised some of the inferior iris that was continuously prolapsing out through the wound.
Odd history indeed!
Exam Findings
More detailed enquiries revealed that the patient had rheumatoid arthritis which was being treated with hydroxychloroquine for the past 35 years. She had bilateral scleral thinning and also advanced peripheral corneal thinning and guttering. Preoperative anterior segment OCT showed extreme thinning. iTrace (Tracey Technologies) refraction showed high astigmatism and distorted mires.
She had developed a mature cataract for which she was scheduled for cataract extraction with toric IOL implantation together with a pinhole pupilloplasty for negating the effect of the higher order aberrations. Examination of the eye showed an inferior gutter dehiscence which had probably occurred solely from the increased pressure to the eye during the peribulbar block. She had been temporarily sutured and referred to me for further management. The other eye showed evidence of challenging surgery. Her fingers and toes showed advanced deformities from the systemic disease. She had gotten a rheumatological clearance for surgery.
I had a couple of thoughts at this time. The sutures were tight. I could do just a primary repair of the wound and leave the cataract for later. Alternately, having been cleared by the rheumatologist, with the disease under remission and with an open eye, I could finish the cataract surgery so that she would be able to see better with this eye. The option would be to close the inferior dehiscence neatly and do a superior cataract extraction. This would however result in a constantly leaking wound during cataract surgery. Moreover, the deep gutter would always be at risk for dehiscence again in the future with any minimal trauma.
I therefore decided to act a little differently and adopt an inverse approach. I chose to do an inverted extra-capsular cataract extraction!
The Approach
I started by making a side port incision at 10 o’clock position and doing an inverted envelope capsulotomy with the flap hinge based superiorly. I then continued not by trying to repair the inferior gutter dehiscence but to actually extend the dehisced area both nasally and temporally along the thinned out cornea in order to get an inverse frown shaped corneal section. I then did an inverted hydrodissection and hydrodelineation and finally expressed the nucleus out in an inverted manner through the inferior corneo-scleral section.
I followed this up by suturing the inferior section and then performing a cortical aspiration with a Symcoe cannula via the inferior access route. There was some zonular instability but the posterior capsule was intact, and I decided to do a supracapsular glued IOL technique. I made two scleral flaps diametrically opposite each other and centered on the pupil.
Usual sclerotomies with a 23-gauge needle would run the risk of extension of the sclerotomy in this eye with thin sclera. Hence, I created the sclerotomy with a 30-gauge needle and fed the leading haptic of the IOL in a supracapsular plane into the 30-gauge needle and then externalized it. The other haptic was also externalized in a similar manner by feeding it into a 30-gauge needle.
Though the angle of approach of the trailing haptic was difficult, I used a haptic fold-over technique to accomplish this. The inferior corneal wound was then neatly closed using a Maloney Intra-operative Keratometer (Surtex) for astigmatic guidance. Intracameral preservative-free triamcinolone acetonide was then used to check for any vitreous and the vitrector was used to excise the envelope capsulotomy’s flap. Both haptics were then tucked into 30-gauge intra-scleral Scharioth tunnels. The iris repair was next attended to by doing a single-pass four-throw pupilloplasty (SFT).
Because the iris had been excised before her referral to me, the lack of iris tissue resulted in a large defect inferiorly which could not be closed any further by more SFT as the taut iris would only cheese-wire. I therefore used an iris hang-back technique to shift the entire iris diaphragm slightly inferiorly in order to close the inferior iris defect. The pupil was then circularized using iridodiathermy. One point of corneal incisional leak persisting despite suturing, was sealed with cyanoacrylate glue. The scleral flaps and conjunctiva were finally closed with fibrin glue.
Postoperatively, the patient was put on a combination of oral and topical steroids, topical cyclosporine, tacrolimus and antibiotics. The patient did well, her corneal incision healed, and she finally regained a best corrected visual acuity of 6/9 (20/30). CP
