The following day, his acuity worsened to 20/200 OD and 20/800 OS, with development of a new 4 mm by 6 mm corneal epithelial defect OS. Given the rapid worsening on topical therapies alone, treatment was escalated to include amniotic membrane transplantation (AMT).
Amniotic membrane consists of the innermost layer of the placental membrane and exerts anti- inflammatory and anti-scarring effects by secreting anti-inflammatory cytokines, inducing apoptosis of immune cells entrapped in the stromal matrix, and downregulating genes related to scar formation by suppressing TGF-beta signaling in ocular surface fibroblasts.4 Commercial amniotic membrane is available as cryopreserved tissue, either in sheets (AmnioGraft, Bio-Tissue) or mounted on a 16 mm diameter ring (PROKERA, Bio-Tissue) which rests on the ocular surface similar to a contact lens.
The rings were placed OU on hospital day 2. By hospital day 4, the patient was intubated and sedated for altered mental status. Sloughing of the conjunctiva beyond the diameter of the rings was observed, indicating areas that could not be treated with device alone. On hospital day 5, the patient underwent surgical placement of sutured amniotic membrane, symblepharon rings and suture tarsorrhaphy for both eyes. Surgical AMT completely covers the ocular surface by suturing the membrane from upper to lower lid margins, at the level of or external to the grey line. The graft was secured into the fornices with a symblepharon ring fashioned from IV tubing, sized appropriately for the patient.4,5
In several case series, treatment with AMT was associated with visual outcomes of 20/40 or better4-6 and reduced the incidence of long-term poor visual outcomes compared to treatment without AMT.7 A recent grading system indicates that the presence of fluorescein staining on greater than 1/3 of at least one lid margin, any corneal epithelial defects, or conjunctival staining larger than 1 cm constitutes severe ocular involvement and should be treated urgently with AMT.6
On hospital day 16, the patient’s tarsorrhaphies were removed. The amniotic membranes had started to dissolve. A complete epithelial defect OD and a central 1 mm epithelial defect OS remained. New diameter rings were placed in both eyes, which then dissolved and were removed on hospital day 20, by which time his corneal epithelial effects had healed. As he convalesced over the next several weeks, his left eye remained stable while small epithelial defects re-appeared and healed in his right eye. He was discharged home after 47 days in the hospital, by which time his visual acuity had recovered to 20/20 OU.
Ophthalmic monitoring continued in the outpatient setting. By 1 week after discharge, all remaining epithelial defects were healed; by 4 weeks after discharge, all topical antibiotic and steroid drops were discontinued. At his last follow-up examination 6 months after discharge, his distance visual acuity remained 20/20 OU. He had mild symblepharon OU and residual inferior corneal scarring OD.