A bayou’s market at the American Academy in New Orleans

First digital retinal imaging, then OCT – the American Academy of Optometry conference has often been the place to see the latest instrumentation making an impact in optometry in the US before it takes off back here in the UK. This year saw a number of newly launched or evolved instruments on display in the exhibition arena (Figure 1) that I feel are worth looking out for.

Screening for glaucoma

I first reported on the Reichert ORA back in 2005. This non-contact tonometer was of interest because, as well as measuring IOP, it also assessed corneal hysteresis (CH). We are familiar with the corneal thickness influencing tonometer measurements and pachymetry is increasingly used by optometrists to see if a higher IOP value might be related to a higher than average corneal thickness (CCT). But what about when thickness is equal – might there be differing resistance to the incoming force of the tonometer related to the specific viscoelastic properties of the cornea. If one is able to measure the force needed to first flatten the cornea and then, having achieved a concave surface, the force on reduction at which the flattening is again achieved, one finds a difference between the two forces – the hysteresis.