68 SURGICAL APPLIED ANATOMY. [Chap, iv 



and to the effects possibly of the discharge directly 

 upon the membrane. 



The lachrymal apparatus. The lachrymal 

 gland is invested by a special fascia which separates 

 it from the general cavity of the orbit ; and, according 

 to Tillaux, this little body can be removed without 

 opening the greater space of the orbit. The gland 

 may inflame, and become so enlarged as to appear as 

 a tumour, which may displace the globe downwards 

 and inwards, and press forwards the oculo-palpebral 

 fold of conjunctiva. If an abscess forms, it most 

 usually breaks through the skin of the upper lid. 

 Cysts of the gland (dacryops) are due to obstruction 

 and distension of some of its ducts. 



The lachrymal sac is situated at the side of the 

 nose, near the inner canthus, and lies in a groove on 

 the lachrymal and superior maxillary bones. On its 

 outer side, and a little anteriorly, it receives the 

 lachrymal canals. In front of the sac is the tendo oculi. 

 If the two lids be forcibly drawn outwards this tendon 

 can be readily felt and seen, and is the great guide to 

 the sac. It can also be felt as it is tightened, when the 

 lids are firmly closed. It crosses the sac at right angles, 

 and at about the junction of its upper third with its 

 lower two-thirds. A knife entered immediately below 

 the tendon Avould about open the middle of the sac, and 

 it may be noted that a lachrymal abscess, when about to 

 discharge, always points below the tendon. Epiphora, 

 or overflow of tears, is due in the main to two causes : 

 (1) To an obstruction in any part of the lachrymal 

 passages from the puncta to the opening of the nasal 

 duct in the nose ; (2) to any cause that removes the 

 lower punctum from its contact with the globe, as 

 may be the case in ectropion, in entropion, in 

 swelling of the lower lid, etc. Facial palsy causes 

 epiphora, because, the orbicular muscle being relaxed, 

 the punctum falls away from the globe, and, moreover, 



