Figure 2. Incidence of postoperative recurrent nerve injury without nerve exposure (period 1, 1979–1990) and with nerve exposure (period 2, 1991–1998, and period 3, 1999). (A) Extensive resections were associated with a higher risk of recurrent nerve injury, in particular in period 1, when the recurrent nerve was not exposed. For subtotal resections there were 14,619, 6,263, and 651 nerves at risk in periods 1, 2, and 3; for near-total lobectomies, the corresponding numbers were 524, 2,412, and 529 nerves at risk. For total lobectomies there were 260, 1,343, and 291 nerves at risk. In all three types of resections, the incidence of recurrent nerve injury declined significantly (P < .01) if period 1 (no nerve exposure) was compared with period 2 (surgery with nerve exposure). (B) The data for subtotal resections have been redrawn with an expanded y-axis to illustrate the significant effect of nerve exposure (P < .001, period 1 vs. 2).