A rigid endoscope was used to directly examine, measure, and photograph the intranasal ostium created by an external dacryocystorhinostomy (DCR). This technique was used to examine 19 patients who underwent 22 standard external DCRs. All patients had clinically successful results, documented by a positive Jone I dye test following surgery. The dimension of the bony opening created at surgery was measured and averaged 11.84 mm in diameter. The average diameter of the healed intranasal ostium was only 1.80 mm. No statistically valid correlation between the size of the bony opening and the final size of the healed intranasal ostium could be established. Thus, a large surgical anastomosis did not necessarily result in a large healed intranasal ostium. Excellent functional results were obtained even when the intranasal ostium was quite small. Other indications for the use of this technique are discussed.