ENTROPION, TRICHIASIS. 75 



about an hour or so, the time being gradually extended. In 

 all cases it is necessary to remove it each evening for cleansing 

 purposes, as if left in altogether it causes a watery, catarrhal, 

 or even purulent, discharge. The improvement in the appear- 

 ance of the animal when the false eye is inserted is very great. 



Excision of the Membrana Nictitans.— Having secured 

 the patient, cause the head to be held as still as possible in a 

 convenient position for the operation. Paint the upper and 

 lower surfaces of the membrana to be removed with some 

 suitable anaesthetic ; allow time for this to act, secure the 

 membrana firmly with a pair of forceps or by passing a fine 

 silk thread through it, and excise with a small pair of curved 

 scissors or sharp scalpel as close to the inner canthus as 

 possible. The slight haemorrhage which follows is easily 

 arrested by the application of a cold wet compress, and no 

 bad sequelae need be feared. In several cases which were 

 kept under close observation for three or four years the 

 animals did not in any way appear to be inconvenienced by 

 the removal of their membranae.^ 



Operation for Entropion and Trichiasis.— The term en- 

 tropion is given to a condition in which the edges of the 

 eyelids turn inwards ; the term trichiasis is applied when 

 the eyelashes turn inwards. The patient should be secured 

 in the abdominal position and the head held firmly by an 

 assistant. The hair is removed as closely as possible from 

 the external surface of the eyelid, and the parts are then 

 anaesthetised with cocaine, or the animal is placed under the 

 influence of some general anaesthetic. An elliptical piece of 

 the offending eyelid is then removed either with a pair of 

 scissors or a scalpel, great care being taken to remove only 

 the skin and not to injure the mucous membrane lining the 

 lid. The wound is then sutured with fine silk or catgut, 

 covered with iodoform (or orthoform) and collodion, and 

 treated as an ordinary small surgical wound ; when only a 



' "Journal of Comparative Pathology and Therapeutics," Vol. VIII., p. 248, 

 "Veterinarian," Vol. LXVII., p. 337. 



