Use of colour Doppler and M-mode ultrasonography to confirm the location of an epidural catheter - a retrospective case series.
Elsharkawy H, Sonny A, Govindarajan SR, Chan V. Use of colour Doppler and M-mode ultrasonography to confirm the location of an epidural catheter - a retrospective case series. Can J Anaesth. 2017 May; 64(5):489-496.