Guidance on the use of non-contact tonometry to measure intraocular pressure (IOP) during the Covid-19 pandemic has been updated.

The Royal College of Ophthalmologists and the College of Optometrists explained that at the beginning of the pandemic, it was uncertain which procedures fulfilled Public Heath England criteria for an aerosol generating procedure.

It was thought that phacoemulsification surgery and air puff tonometry posed a risk and advice was to avoid its use in all clinical settings.

Expert consensus, based on more recent evidence, is that there is a low likelihood of viral particles in the tears and conjunctiva, even in patients with active Covid-19 injection or conjunctivitis.

It is now accepted to restart the use of air puff tonometry in primary and secondary care, after undertaking a local risk assessment and following other Covid-19 related advice.

The professional bodies advised that the instrument head is wiped with disinfectant and three puffs should be performed between each patient to clear the tip.