title: The osmotic variable.
abstract: Patients were found to differ in their prefitted tear osmotic baselines. Although such differences appeared small, they did represent the "safety margin" (i.e., against osmotic edema) each patient had against a "hypotonic shift" when receiving a hard (PMMA) contact lens.
mesh_terms: D003261:Contact Lenses / Q000009:adverse effects*; D004487:Edema / Q000209:etiology*; D006801:Humans; D009997:Osmotic Pressure; D013666:Tears / Q000502:physiology*