Congenital fistula of lacrimal duct.

CONGENITAL fistula of the lacrimal duct is very rare, and is usually associated with other congenital anomalies (Duke-Elder, 1932, 1952; Gray, 1949; Spaeth, 1948). The epithelium of the ducts and alveoli of the lacrimal gland is derived from a series of ectodermal invaginations in the region of the superior conjunctival fornix. Early buds form the orbital portion, while secondary buds from above appear later and form the palpebral lobe at the 40-60 mm. stage of the foetus. The stalk of the ectodermal invaginations, at first solid, are later canalized (50-55 mm.). The full development of the gland occurs at about 3 to 4 yrs. The gland ducts are about twelve in number, two to five being derived from the orbital lobe, and six to eight from the palpebral lobe; they all pass through the palpebral lobe as would be expected from their development. The majority of ducts open into the lateral part of the superior fornix, but a large duct (which may be called the inferolateral duct) traverses the extreme outer end of the gland, passes just deep to the conjunctival epithelium, and opens a few millimetres lateral to and some distance below the external commissure. The case described below is that of a little girl who had a congenital fistula of the right inferolateral lacrimal duct and right dacryocystitis with no associated deformity of the external canthus or elsewhere.