PURPOSE: To map the sensitivity and staining of the marginal conjunctiva in soft contact lens (SCL) wearers and nonwearers and to investigate diurnal changes. METHODS:Thirty-five nonwearers and 35 SCL wearers were recruited. Mechanical sensitivity was measured at 8 locations on the ocular surface and adnexa (cornea, marginal, bulbar, and tarsal conjunctivae) using the Cochet-Bonnet aesthesiometer. Lid margin staining (lissamine green) was assessed through image analysis. Measurements were repeated at 12 hours in 11 nonwearers and 10 symptomatic SCL wearers. RESULTS: The marginal conjunctiva was the most sensitive conjunctival region (all P < 0.001). There was no significant difference in sensitivity at 12 hours (all P > 0.05). There was a significant difference in sensitivity between the 2 groups in the morning for the lower lid tarsal conjunctiva (P = 0.003). After 12 hours, the sensitivity of the lower lid marginal conjunctiva was found to be reduced in SCL wearers compared with nonwearers (all P < 0.05). Lower lid margin staining was greater than upper lid margin staining in both groups (all P < 0.05). In the SCL wearers, a significant increase in lower lid margin staining was found at 12 hours compared with the morning (P = 0.04). After 12 hours, lower lid margin staining was significantly greater in SCL wearers compared with nonwearers (P = 0.03). CONCLUSIONS: This work has demonstrated that the marginal conjunctiva is the most sensitive conjunctival region. After 12 hours, symptomatic lens wearers showed decreased sensitivity of the lower marginal conjunctiva and increased lower lid margin lissamine green staining compared with those of the nonwearers.
RCT Entities:
PURPOSE: To map the sensitivity and staining of the marginal conjunctiva in soft contact lens (SCL) wearers and nonwearers and to investigate diurnal changes. METHODS: Thirty-five nonwearers and 35 SCL wearers were recruited. Mechanical sensitivity was measured at 8 locations on the ocular surface and adnexa (cornea, marginal, bulbar, and tarsal conjunctivae) using the Cochet-Bonnet aesthesiometer. Lid margin staining (lissamine green) was assessed through image analysis. Measurements were repeated at 12 hours in 11 nonwearers and 10 symptomatic SCL wearers. RESULTS: The marginal conjunctiva was the most sensitive conjunctival region (all P < 0.001). There was no significant difference in sensitivity at 12 hours (all P > 0.05). There was a significant difference in sensitivity between the 2 groups in the morning for the lower lid tarsal conjunctiva (P = 0.003). After 12 hours, the sensitivity of the lower lid marginal conjunctiva was found to be reduced in SCL wearers compared with nonwearers (all P < 0.05). Lower lid margin staining was greater than upper lid margin staining in both groups (all P < 0.05). In the SCL wearers, a significant increase in lower lid margin staining was found at 12 hours compared with the morning (P = 0.04). After 12 hours, lower lid margin staining was significantly greater in SCL wearers compared with nonwearers (P = 0.03). CONCLUSIONS: This work has demonstrated that the marginal conjunctiva is the most sensitive conjunctival region. After 12 hours, symptomatic lens wearers showed decreased sensitivity of the lower marginal conjunctiva and increased lower lid margin lissamine green staining compared with those of the nonwearers.