Since good ventilation of the middle ear is a pre-requisite for successful myringoplasty, it was our policy to investigate the tubal function in dry central perforation of the eardrum and to correlate the manometric and endoscopic findings. Nasal endoscopy proved to be indispensable in diagnosing mechanical tubal obstruction and in localizing and even treating ‘hidden’ lesions in key areas, with probable normalization of the tubal function. The correction of the mechanical tubal obstruction must precede ear surgery. Whenever tubal obstruction is diagnosed as functional or idiopathic, the ventilation of the middle ear should be guaranteed during ear surgery by addition of a tympanostomy tube to the graft or drum remnant, and a guarded prognosis given.