656 Congenital Hydrocephalus. Tumors of the Brain. 



In cases in wliicli there is impaction of the intestine medici- 

 nal treatment may be resorted to and it is best to give large 

 doses of nentral salts, althongh now and then aloes ma^^ be nsed 

 witli advantage. In cases where there is loss of conscionsness 

 two or three snbcutaneons injections of pilocarpin hydrochloride 

 (0.30-0.50 g.) or arecolin (0.05-0.10 g.) give some relief. Viborg 

 and later Dieckerhoff advised tincture of veratrine. Six to 

 eight grams were injected intravenously and as long as there 

 Avas difficulty of respiration, sweating and nausea the animals 

 were left loose in a large box. In acute attacks the same treat- 

 ment as used in acute meningitis is indicated (see page 604). 



Hayne advised puncture of the olfactory bulbs so as to allow the liquid to 

 escape. This treatment is dangerous as it may lead to a fatal meningitis and 

 produces no lasting results (Hering, Eoll, Dieckerhoff). 



Literature. Dexler, Z. f. Tm., 1899, 242 ..(Lit.).— Droge, Z. f. Tk., 1907, 

 496.— Meissner, B. t. W.. 1899, 239.— Schindelka, 6. Z. f. Tk., 1891, IV, 106. 



Congenital Hydrocephalus. (Hydrocephahis interniis congenitus). 

 This developmental anomaly is equally common in foals, calves, lambs, 

 and dogs, and the condition is more pronounced than the acquired dis- 

 ease. In very pronounced cases the brain appears to be enclosed in a 

 thin-walled sack, which is filled with a clear or slightly turbid serous 

 liquid, the medullary substance forming a thin layer inside the wall. 

 Since during fetal life the bones of the cranium are not yet joined ; the 

 cranium enlarges enormously, the parietal and frontal bones bulge, and 

 the orbits are reduced in size, and the head assumes a characteristic 

 shape, the cranium being large out of all comparison with the rest of 

 the head. Such a head may lead to dystokia. As a rule, the animals 

 die soon after birth, but they sometimes remain alive ; and apart from 

 the abnormal shape of the cranium, show no symptoms of disease, al- 

 though the cortex of the brain mav be almost entirelv a))sent. (Forgeot 

 & Nicolas, Bull, de la Soc. des Sci.'Vet. de Lvon, 1906, 115.— Jellinek, T. 

 Z., 1907, 435.— Marchand & Petit, Bull., 1907, 261.) 



12. Tumors of the Brain. 



Occurrence. Tumors within the cranium are of very rare 

 occurrence. In the brain itself the socalled cholesteatoma* 

 is comparatively frequently found. Dexler found them in 22.5 

 per cent of 204 horses examined. They develop in connection 

 with the venous plexuses beneath the cerebellum or in the lateral 

 ventricles. The majority are about the size of a pea, but in 

 some cases they attain the size of hen's or goose's eggs. As 

 a rule they cause no disturbance of health. By investigations 

 with tlie polarization microscope Schmay showed that clioles- 

 teatomata present the characters of chronic granulating in- 

 flammation and has termed them granuloma cholestrinicum. 



*(Tlie type of neoplasm referred to by continental authors as cholesteatoma is 

 termed, in English veterinary literature, psammoma, the name cholesteatome being reserved 

 for a growth of a totally different nature which is very occasionally met with in the substance 

 of the cerebral liemispheres. — Translator's Note.) 



