Temporalis fascia, placed as an underlay graft, is commonly used to re
pair tympanic membrane perforations. Graft failure, however, is a well
recognized complication. Grafts are often allowed to dry out during t
he procedure and, therefore, are often positioned in a dry or partiall
y dehydrated state and only become fully rehydrated after placement. T
his study looked at how the size of the temporalis fascia alters with
its state of hydration. The size of 20 temporalis fascia grafts was me
asured when fresh, after flattening and allowing them to dry, and fina
lly after rehydrating the grafts with 0.9 per cent saline solution. Si
gnificant shrinkage was demonstrated. It is therefore proposed that a
cause of increased failure rates, particularly in anterior myringoplas
ties, is loss of underlay due to graft rehydration and shrinkage. Thus
graft shrinkage should be considered when positioning the graft.