Editor,—Canalisation of the nasolacrimal apparatus usually occurs at the same time throughout its length. However, its distal end has been shown to be occluded by a membrane in 73% of otherwise normal stillborn fetuses at term.

For typical dacryocystocoeles, a regimen of warm compresses and massage, with regular ophthalmological review to check for the first signs of dacryocystitis, seems to be reasonable. Should dacryocystitis supervene, the child should be admitted to hospital for the intravenous administration of antibiotics and probing of the nasolacrimal apparatus. Should the dacryocystocoele recur or epiphora ensue, and repeated probing does not give the result, it may be necessary to intubate the nasolacrimal apparatus or perform a dacryocystorhinostomy. In 1893, Caldwell described the first case of an endonasal operative approach to the lacrimal system. This technique was later modified by West and supported by Mosher in 1921. In spite of these attempts, the external dacryocystorhinostomy (DCR)—the technique inaugurated by Toti in 1904—was, for a long time, the most accepted procedure for lacrimal sac surgery. The reason for this was presumably limited transnasal visualisation caused by bleeding during endonasal dacryocystorhinostomy. …