8 Charles Russell Bardeen 



longed application of the tube containing the radium salt to the 

 head or spine of a small mammal was followed by paralysis, ataxia, 

 convulsions and death. In the central nervous system marked 

 hemorrhagic lesions were found after death. Similar alterations 

 in the central nervous system have been described by Heineke,^* 

 Scholtz,"^ Obersteiner,^^ and others. Obersteiner, who paid espe- 

 cial attention to the lesions of the central nervous system, con- 

 cludes that "the various phenomena which are observed in the 

 exposed mice, including the death which follows sufficient exposure 

 to the rays, in greatest part are, directly or indirectly, merely an 

 expression of a general disturbance of the circulation and of meta- 

 bolism produced by the radium rays." Obersteiner does not con- 

 sider the nerve cells specifically susceptible to the rays although 

 they are, more easily than many tissues, disturbed by altera- 

 tion in the circulation or general metabolism. The general dis- 

 turbances produced by the rays are indicated by the increased 

 elimination of nitrogen discovered to take place by Baermann and 

 Linser^® after severe exposure. Lepine and Bonlud^° had previously 

 shown that alterations affecting metabolism take place in the 

 pancreas, liver and blood after -exposure to the Roentgen rays. 

 The great susceptibility of the nervous system to the indirect, if not 

 to the direct, action of the rays, is shown not only by the lowering 

 of the reflexes, apathyandparalysiswhich precede death in animals 

 sufficiently exposed to the Roentgen or the radium rays, but also by 

 the injury of the retina and secondary atrophy of the optic nerve 

 which Birch-Hirschfeld" has described. Trophic disturbances 

 may likewise possibly be due to the injured nervous system. 

 Obersteiner*^ has described a severe panophthalmitis and a gan- 

 grene of the tendons of the feet, the ears and the nose following 

 exposure of mice to radium. 



While there is doubt concerning the specific sensibility of the 



^'Heineke: Miinchener med. Wochenschrift, 1, s. 2090, 1903. 



^'Scholtz: Deutsche med. Wochenschrift, xxx, s. 54> 1904. 



^'Obersteiner: Arbeiten aus dem Neurologischen Institute, Wien, xii, p. 86, 1905. 



^'Baermann and Linser: Op. cit, 



''"Lepine and Bonlud: Comptes Rendus de I'Acad. des Sciences, Paris, t. xxxviii, 1904. 



■*'Birch-Hirschfeld: Miinchener med. Wochenschrift, 1904. 



^^Obersteiner: Op. cit. 



