Follow up of patients with ocular scarring secondary to LOC syndrome treated by amniotic membrane transplantation

Aims: To document and discuss the long term outcome of a new ophthalmic treatment for laryngo-onycho-cutaneous (LOC) syndrome. Methods: Two children were treated by excision of ocular granulation tissue and ocular surface rehabilitation with frozen amniotic membrane (AM). The clinical course of both patients was followed and documented at 2 years and 4 years following the surgery. Results: Patient 1 demonstrated limited recurrence of granulation tissue at 10 months. After 36 months, re-growth of granulation and scar tissue required a further three subsequent operations to the right eye in an attempt to keep the optical axis clear. 4 years postoperatively, neither eye has a clear visual axis. In contrast similar surgery for the right eye of patient 2 has been highly successful, with only very limited non-progressive recurrence after 2 years of follow up. The operation to the left eye has been similarly effective although the follow up is only 6 months. Conclusions: Ocular surface rehabilitation with AM is the first partially effective treatment for the eye complications of LOC syndrome. The surprising benefit from AM may stem from the primary pathology of the condition. LOC syndrome is caused by a genetic defect resulting in an unusual N-terminal deletion of the α3a chain of the basement membrane protein laminin 5. One mechanism through which AM transplantation may act to reduce ocular scarring in this disease is to supplement the abnormal secreted laminin 5 with healthy transplanted laminin. Despite its initial efficacy one episode of AM treatment does not guarantee long term control of the scarring process and variations in AM graft efficacy may be related to other complicating factors such as limbal stem cell deficiency or severity of the initial scarring process.