Dacryocystorhinostomy. Diagnosis and treatment of nasolacrimal canal obstructions.

Since Toti's original description of the dacryocystorhinostomy (CDR) in 1904, most surgery for relief of lacrimal obstruction has been performed through an external incision. Although the endonasal approach was for the first time introduced by Caldwell in 1893, its use stayed limited due to difficulties in visualizing the endonasal structures during the operation. The advance of the operating microscope and later a rigid endoscope into the surgery awakened interest for the endonasal approach. Endonasal DCR surgery has the advantages of preventing a scar on the skin and preserving the pump function of the naslacrimal sac. If the surgeon is experienced in endoscopic or microscopic surgery, correct localization of the window and addressing possible other nasal pathologies is possible in the same session. The endonasal laser DCR is not the first operation to be preferred due to the high cost, longer operation time, and less satisfactory results. It may be an alternative in cases with a tendency to bleeding. Endonasal surgery can not help canalicular problems. In these cases external surgery should be preferred. In revision cases, the endonasal approach is preferred by almost all authors. Even in external surgery, endoscopy may accompany the external approach to check the site of the fistula. Silicone intubation may be used routinely for two months to have better results, but no longer than 3 months to avoid complications. Silicone intubation is especially recommended in canalicular stenosis, small scarred lacrimal sacs and in reoperations. In this review article, diagnostic tests and various surgical methods, the advantages and disadvantages, were compared. Reasons for failure after surgery are also discussed.