Beyond Eye Rubbing: Mechanical Ocular Stimulation Is Highly Prevalent in Keratoconus

Objectives: To investigate current and previous mechanical ocular stimulation behaviors beyond conventional eye rubbing in patients with keratoconus. Methods: This prospective study included Japanese outpatients with a clinical diagnosis of keratoconus in at least one eye. All participants completed a structured investigator-developed questionnaire assessing current and past mechanical ocular stimulation behaviors, followed by face-to-face physician interviews. Questionnaire items included history, reasons, duration, frequency, techniques, and anatomical sites of stimulation. Results: A total of 304 patients were included, with 91.4% reporting mechanical ocular stimulation. These behaviors were typically long-standing (75.9% >10 years) and varied widely in motivation, frequency, methods, and anatomical sites. Ocular itching was the most common trigger (75.9%), although many behaviors were unrelated to itching. Finger pulp (56.1%) and knuckles (48.6%) were commonly used, and the medial canthus was the most commonly involved site (70.1%) ( P <0.05). Pressure-related behaviors, such as eye pressing or massage during fatigue, were reported by approximately one third of patients. Conclusions: The concept of mechanical ocular stimulation provides a more comprehensive framework than eye rubbing for characterizing pressure-related behaviors in patients with keratoconus. Broader assessment of current and past behaviors may improve clinical assessment and patient counseling.