Borgstein, J.A.

patient middle ear surgery atelectasi middle retraction stage pocket children borgstein retraction pockets study hearing cholesteatoma tympanic membrane membrane group preoperative problem otiti tympanic retraction pocket postoperative result nerve classification disease media procedure otitis media treatment ventilation tube insertion approach iris diameter intervention bone conduction thresholds cause erosion difference infection ventilation eardrum threshold perforation borgstein j conduction structure photograph process observation middle ear structures success rate preoperative abg ossicular chain technique excision airway healing ventilation tube postoperative abg damage month promontory signi success diameter antibiotic ossicular perforations obstruction aspect laryngeal vertigo coronal plane larynx ficant stage i stape management ossicle