Surgical Treatment of 32 Cases of Long-term Atopic Keratoconjunctivitis Using the Amniotic Membrane

J Yang; F-h Yang; C-H Peng; D Erol; S H Tsang; X-r Li


Eye. 2013;27(11):1254-1262. 

In This Article

Materials and Methods

This study was approved by the Institutional Review Board of Tianjin Medical University Eye Hospital in Tianjin, China. Over a period between 2005 and 2012, a total of 37 subjects (25 male, 12 female; ages between 5 and 61 years, mean 37.97 years) with a confirmed diagnosis of AKC were recruited. AKC was diagnosed based on the following features, as described by Guglielmetti and colleagues:[7] the disease is associated with other atopic conditions (rhinitis, eczema, or asthma), occurs at any time point in the course of associated atopic disease, and is combined with evidence of corneal involvement, independent of degree of severity of atopic disease.

These 37 cases had a long history of misdiagnoses and mismanagement. They had responded poorly to conventional anti-allergic treatments. Typical treatments were potent mast cell stabilizers and low-dose corticosteroids: 0.1% olopatadine hydrochloride ophthalmic solution twice per day (Patanol; Alcon Laboratories, Fort Worth, TX, USA), 0.2% cyclosporine A eye drops 4 times a day, tobramycin/dexamethasone eye drops 4–6 times per day (Tobradex; Alcon Laboratories), and artificial tears 4 times per day. In some cases, a subconjunctival injection of dexamethasone was added twice per week. However, most of corneas still displayed severe resistant epithelial defects, erosions, or ulcerations (Table 1) more than 1 month into treatment. We offered surgical intervention for these cases. Thirty-two subjects provided written informed consent to take part in the study after an explanation of the nature, risks, and possible adverse consequences of the procedures. Five patients who chose not to undergo surgical treatment, but instead were treated with medication, served as control group.

Human amniotic membrane and preserved corneal tissue were used for these treatments. AM and glycerol-preserved corneal patch grafts were prepared as previously described.[8,9] All membranes and grafts were screened by blood serum testing to exclude the human immunodeficiency virus, hepatitis virus type B, hepatitis virus type C, and syphilis.

In this study, cases involving recurrent and refractory corneal epithelial defection were treated by AMT. The procedure was as follows: a single layer of AM equivalent in size to the corneal epithelial defect was selected and sutured along the defection border with the membrane stromal side facing down. Cases featuring recurrent corneal erosions were treated with amniotic membrane covering (AMC). The membrane surface was sutured to cover the entire corneal surface extending beyond the limbus. Surgical debridement was performed before the tissue covering was set in place. A single layer of membrane with stromal side down was secured to the conjunctiva with a running 10-0 nylon suture.

Fillings were used for small perforations. When a corneal ulcer with perforation was evident, and the size of ulcer and microperforation were not >1.5 mm, we used the amniotic membrane to fill in the gaps in tissue left behind by the ulcer and microperforation. Three star-shaped sutures were used to ensure that the AM filled the holes in the cornea tightly. Another single sheet of amniotic membrane with a larger perimeter than the wound was used to cover the filling, allowing it to heal.

Alternatively, in corneas with perforations of >1.5 mm in size, graft corneal transplants and amniotic membrane filling (AMF) were performed in quick succession. Donated glycerol-preserved corneal grafts were placed into sterile saline for recovery. The grafts were then fitted to the size of the perforation and placed in the eye of the host in the deep stromal layer secured in position by edge to edge sutures. The amniotic membrane was used to fill in the space between the corneal graft and a top lager layer of AMC, as needed. This larger layer of amniotic membrane was selected to cover the whole area with the defect. Tissue was trimmed to fit the shape of the ulcer and sutured with interrupted 10-0 nylon sutures.

After the surgery, all patients were treated with anti-allergic and anti-inflammation medications for durations of at least 2 weeks. Doses of the medication were adjusted at follow-up. For these follow-up appointments, patients were asked to return at 1, 2, and 4 weeks postoperatively, and then at 3, 12, and 24 months. In addition, patients returned whenever any recurrent episodes occurred. At each postoperative visit, each patient underwent a complete ocular examination with imaging by slit-lamp photography. The period of recovery, as determined by reduction of ocular inflammation, the recovery of corneal epithelium, the recovery of anterior chamber, and the reconstruction of cornea, was recorded in days.

If healing was completed within 3 months, the surgery was classed as a short-term or primary success. If long-term follow-up found no recurrence of inflammation, an absence of postoperative corneal melts, no persistent epithelial defects, and significant and sustained restoration of vision, the surgery was classed as a long-term or secondary success.