The rate of spontaneous healing of tympanic membrane perforations in relation to time after blast injury, size, and location of perforations, was evaluated in 147 patients (210 ears). In 46 patients a paper patch was placed over the perforation. Spontaneous healing was seen in 155 ears (74%), 131 (62%) healed within the first 3 months and 145 ears (69%) healed within 10 months. Large and central kidney-shaped perforations had the least tendency to heal and usually required surgical intervention. Tympanoplasty was performed on 33 ears (15%), ossiculoplasty on 5 and mastoidectomy on 10. Intervention is recommended when the tympanic membrane remains unhealed for at least 10 months.