Related Experiment Video
Updated: Jul 20, 2026

A Novel Approach for Documenting Phosphenes Induced by Transcranial Magnetic Stimulation
Published on: April 1, 2010
Pressure phosphene self-tonometry in a patient with Posner-Schlossman syndrome
Dexter Y L Leung1, Srinivas K Rao, Dennis S C Lam
1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, Kowloon, Hong Kong, China.
Abstract:
Studies have shown that pressure phosphene tonometry (PPT) may be applied to glaucoma patients. It has the potential for patients to self-monitor the intraocular pressure (IOP) at home. We describe the successful use of this approach in a patient with Posner-Schlossman syndrome. In the first part of the study, we investigated whether our patient could use PPT accurately and reliably. In the second part of the study, our patient performed daily home self-tonometry, and was educated to seek ophthalmic assessment if his self-measured IOP was >or=21 mmHg. The outcome measurements included IOP and the number of unscheduled attendances for ophthalmic assessment. The use of PPT reduced his number of unscheduled hospital visits from 0.82 to 0.47 visits per month. PPT can be applied with accuracy, reliability and safety in patients with Posner-Schlossman syndrome, with potential benefits in reducing unnecessary ophthalmic attendances by nearly 50%.

