Cliunia. 3^1 



Retinal gliomata of man spread out as grayish nodular tumors 

 over the inner surface of the globe of the e\e, but are also met per- 

 forating the sclera, growing along the optic nerve and perhaps es- 

 caping into the orbit ; they occur as congenital growths sometimes 

 involving both eyes, and have been observed in a few instances in 

 several children of the same parents. For these reasons and be,- 

 cause of their structure they may invariably be referred for their 

 origin to developmental faults. They are only in part composed 

 of glia tissue, being principally made up of neural epithelium of 

 the retina reverted to embryonal type, arranged in thick sheath- 

 like layers around the synchronously proliferating bloodvessels. 

 [These so-called retinal gliomata are the subject of considerable 

 controversy. The presence of any true glia tissue comparable 

 to that of the brain is in itself questionable, and the evident part 

 taken by the retinal neuroepithelial tissues has led to their being 

 denominated neuroepitheliomata. These neuroepithelial cells are 

 frequently found in a so-called rosette arrangement, as the cylin- 

 drical epithelium seen in sections of small ducts. The tumor in 

 its infiltrating and metastatic character is a very different growth 

 from the glioma of the brain ; the former is rapidly fatal, while 

 the latter shows little tendency lieyond a slow peripheral infiltra- 

 tive enlargenient to extend, and persons may have harbored these 

 growths for years with little definite evidence of their presence. 

 The more separate arrangement of the cells of the true glioma, 

 the branching fibrils of the cells preventing close adjustment, is 

 not seen in the retinal glioma, whose cells are very closely packed and 

 evidently have but few^ and insignificant projections upon them 

 (in fact one must examine with great care even after special 

 staining to think that these projections exist in any comparable 

 degree). The editor would regard favorably the separation of 

 these growths from the class of true gliomata, preferring the 

 more distinctive and well justified term of neuroepithelioma. 



The true glioma of the brain is usually single; sometimes sev- 

 eral have been found, usually in close relation and probably in 

 reality representing the same growth. A\hen pure and free from 

 sarcomatous combination the tumor should be regarded as rela- 

 tively benign save for its pressure effects. Distant metastasis is 

 rare; although local metastasis from peripheral infiltration is 

 the rule.] 



