Rigid contact lens adherence: incidence, severity and recovery

The incidence of rigid lens adherence in one eye of 25 subjects was compared to the results for the fellow eye wearing a soft lens of nearly equal permeability in an in-laboratory overnight study. A 48% incidence of adherence was found for both extended wear modalities, which demonstrates the high frequency of this problem. Adherence of both rigid and soft lenses caused epithelial breakdown and corneal distortion, but these sequelae were generally more severe with rigid lenses. Recovery data on nine subjects whose rigid lenses adhered show that positive signs of adherence often disappear within 1 hour, demonstrating the need for early morning examinations. Practical considerations for the detection of rigid lens adherence and the possible consequences of failure to diagnose this condition are discussed.