An electrosurgical instrument is provided for the treatment of tissue, the instrument (3) comprising an instrument shaft (14) having a longitudinal axis, a suction lumen (16) extending at least partially along the instrument shaft, and a chisel electrode (21) at the distal end of the shaft. The chisel electrode (21) includes a body portion (22) at a first angle with respect to the longitudinal axis, and a hook portion (23) extending from the body portion at a second angle to the longitudinal axis. The chisel electrode (21) also includes a plurality of apertures (35, 36, 37, 38, 40) providing a suction lumen through the electrode, there being at least one aperture (35, 36, 37, 38, 42) in the body portion (22), and at least one aperture (40, 45) in the hook portion (23).
