Total ocular surface amniotic membrane transplantation for treatment of paraquat-induced chemical ocular surface injury

Abstract

Objective To investigate the clinical feature of paraquat-induced acute severe chemical ocular surface injury and the therapeutic efficacy of total ocular surface amniotic membrane transplantation for treatment of ocular surface damage.Methods Eight patients (8 eyes) with paraquat-induced ocular surface injury who were treated in shandong eye hospital from march 2011 to August 2012 were studied and asked for details of the medical history.Slit lamp were used to observe the characteristics of palpebral margin,conjunctiva and corneal damage.The patients underwent total ocular surface (Including palpebral conjunctiva,bulbar conjunctiva,fornical conjunctiva and cornea) amniotic membrane transplantation combined with systemic and local glucocorticoid treatment for 3 days after the surgery.Visual acuity,recovery of ocular surface after surgery and tear was record.Results Damage features:(1) Palpebral margin was characterized by edema and hyperaemia.Meibomian gland orifices were hard to see clearly.(2) Palpebral conjunctiva and bulbar conjunctiva manifested as edema and hyperaemia.All conjunctiva (including palpebral conjunctiva,bulbar conjunctiva and fornical conjunctival) were covered by grayish pseudomembrane.Large bright red and bleeding wound can be seen when the pseudomembrane had been removed.Two patients whose medical history was more than 10 days with different extent of pseudomembrane detachment gradually began to produce symblepharon from fornix.(3) Cornea was characterized by diffuse edema,corneal opacity,or may be associated with corneal epithelium defect.Treatment outcome:All of patients' visual acuity restored to preoperative levels.Amniotic membrane dissolved in 7 to 14 days with no symblepharon.Conjunctival appeared smooth and flat.Corneal transparency gradually restored.The corneal epithelization process was completed with negative fluorescence staining.Follow-up to 3 months,there was no symblepharon.Lots of meibomian gland orifices jamed in order to the scar formation of Palpebral margin.The patients presented with different degree of tear secretion decrease.Conclusions Paraquat-induced chemical ocular surface injury is characterized by pseudomembrane of all conjunctiva and can cause serious ocular surface damage.Complications,such as symblepharon,will be effectively reduced by having total ocular surface amniotic membrane transplantation timely. Key words: Chemical ocular surface injury; Amniotic membrane; Transplantation