It's important to evaluate tear osmolarity during surgical planning to ensure that pre-surgical keratometry readings are not compromised by hyperosmolarity of the ocular surface.

That was the take-home message from the preliminary results of the TearLab Cataract Study, which were presented at the 2014 Congress of the European Society of Cataract and Refractive Surgeons (ESCRS).

The study of 67 patients found that hyperosmolar patients demonstrated a wider variation in keratometry calculations between visits relative to the normal osmolar group. In the hyperosmolar group, 16% of hyperosmolar eyes had more than 1 dioptre of change in K cylinder values between the first and second visit.

The preliminary results of this study evaluating the relationship of a hyperosmolar tear film on keratometry readings were presented by Dr Doyle Stulting, president of the Stulting Research Center, Woolfson Eye Institute, Atlanta, Georgia, USA.

The study results will be submitted for publication to the 

Journal of Cataract and Refractive Surgery