Abstract
Introduction Accurate characterisation of the physical properties of the retina is essential for understanding the effects of age, disease mechanisms and developing effective surgical interventions. Ex vivo measurements have been used to do this, however the effect of storage conditions on the results of these biomechanical tests are unclear.
Aims The objective of this study was to investigate effects of commonly used laboratory storage media on the mechanical performance of retinal samples.
Methods Freshly enucleated porcine eyes were dissected, and superior vertical strips taken. Strips were incubated in phosphate buffered saline (PBS), balanced salt solution (BSS) Ringer’s solution and extracted porcine vitreous (control) for 60 minutes at 4°C. Sixteen 3x9mm strips of porcine retina, 4 per group, were subjected to uniaxial load to failure testing post incubation. Strip thickness was determined by light microscopy.
Results The mean maximum stress was closest to the control (5.6KPa) for BSS (7.4KPa) followed by Ringer’s solution (1.6KPa) then PBS (0.4KPa). All changes were significantly different to the control (P<0.05).
Conclusion The biomechanical properties of porcine retina are highly variable depending on the media they are stored in pre-testing. Strips incubated in BSS provided results closest to the control samples. Caution should be taken when considering results taken from different storage media when assessing biomechanical changes in the retina and other soft tissues.
Acknowledgements The Dunhill Medical Trust
