Post-operative assessment of perfusion of deep inferior epigastric perforator (DIEP) free flaps via pulsatility index (PI) using a portable colour Doppler sonogram device - Arya, R; Griffiths, L; Figus, A; King, D; Ramakrishnan, V; Griffiths, M (J Plast Reconstr Aesthet Surg, 2013)