Surgical Results of Retrograde Mastoidectomy with Primary Reconstruction of the Ear Canal and Mastoid Cavity

Table 2

Audiometric results before and after surgery.

Audiometric results
	Mean	SD	value
PTA before surgery, dB HL	54.28	20.54
PTA after surgery, dB HL	48.58	21.58
^*PTA changes, dB = before surgery − after surgery	5.70	13.60	<0.001
ABG before surgery, dB HL	29.22	13.04
ABG after surgery, dB HL	22.25	11.11
^*ABG changes, dB = before surgery − after surgery	6.96	10.97	<0.001

PTA: pure-tone average; ABG: air-bone gap; ^*paired -test.