Transnasal dacryocystorhinostomy.

The advantages of the transnasal approach to dacryocystorhinostomy over the external incision approach are numerous. The external incision, with dissection of the orbicularis muscle, medial canthal ligament, and other soft tissues, produces much more scarring and is more likely to interfere with the pump action of the orbicularis muscle on the canaliculi. Granulation tissue and scar stenosis are the causes of failure in both the external approach and transnasal surgery. In fact, if follow-up care by a nasal surgeon is not available with the external approach, the failure rate will be higher than with transnasal surgery. Patients who require dacryocystorhinostomy should be advised of the choice of procedures.