Basic Problems in the Histopathology of 

 Radiation of the Central Nervous System 



Orville T. Bailey 



University of Illinois College of Medicine, 

 Chicago, Illinois 



This survey of the histopathologic chans^es resuhins; from radiation of the 

 central nervous system will be confined to those detected by light microscopy 

 in postnatal experimental animals and largely to the effects of gamma and 

 roentgen radiation. Its purpose is to state some of the problems in tissue 

 reaction following radiation as they are met by the neuropathologist and 

 to illustrate rathei than offer solutions for these questions. 



Materials and Methods 



A series of experiments were carried out over many years in the Neuro- 

 surgical Research Laboratory of the Children's Medical Center. Boston, 

 under the direction of Dr. Franc D. Inoraham. in association with Drs. E. A. 

 Bering, Jr.. R. L. McLaurin and others. Many results of these studies have 

 been published Bailey ct al., 1957, 1958; Bering ft ai. 1955: McLaurin ct 

 al., 1955 1. but the histologic findinss. especially in the spinal cord, ha\e not 

 been described in detail. 



The experiments were of three types. In the first, tantalum'"-' wires co\- 

 ered with polyethylene were inserted into the cerebral cortex of 40 monkeys 

 (Macaca mulatta and Atelcs geoffroy). 1.5-2.0 mm posterior to the motor 

 strip of the right cerebral hemisphere. The wires were removed after 2.5- 

 4.770 r had been deli\ered. Monkeys were allowed to sur\ive from 2 hoius to 

 33 months after completion of radiation. The polyethylene encasement was 

 regarded as sufficient to pre\ent any tissue effects of beta radiation from the 

 activated tantalum wire. 



In the second series of experiments, a piece of tantalum wire acti\ated in 

 the atomic pile at Oak Ridge was encased in polyethylene and placed on the 

 dorsal surface of the spinal cord or, in a few animals, beneath the skin over- 

 lying the spine and fixed in place to the paravertebral fascia ! . Experiments 

 were carried out in 18 Macaca mulatta monkeys with dosages varying from 



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