The invention relates to an apparatus for applying heat to a targeted region of tissues comprising: a cannula having a proximal end for insertion to the targeted region of tissues; and means for transmitting a heat generated by a heat source to the proximal end of the cannula, characterised in that a temperature sensing unit is disposed within the cannula, at a position adjacent to the proximal end of the cannula to measure the temperature of the proximal end and feedback to a processor for controlling the heat source.