The PSNI says Dr Hegarty disturbed an intruder at the premises on the Buncrana Road around 5.30am.
It appears access had been gained through a window.
The intruder is described as around 1.68m (5' 6") tall, wearing a cap and a light-coloured top.
It is not thought at this stage that anything was taken from the house.
SIC: RTÉ