Hydro chronicles.

This article is based on the 2025 ASCRS Binkhorst Lecture which I delivered in Los Angles in April 2025. It will focus on the basic but oft-neglected step in phacoemulsification: hydrodissection. Over a 40 year career, I have had a particular interest in the techniques of 'hydro' manoeuvres to achieve nuclear mobility. The introduction of intra-operative OCT in 2017 allowed 'live' imaging of hydrodissection and hydrodelamination helping in our understanding of cleavage planes. Complications of hydrodissection like the 'pupil snap sign' will be analysed and the relevance of hydrodissection in modern cataract surgery discussed.