452 THE PINEAL ORGAN 



This was probably a remnant of the dorsal diverticulum, which was present 

 during foetal life and projects backwards over the pineal body from the posterior 

 part of the roof of the third ventricle. This figure should be compared with 

 Fig. 304, which represents a small cyst, lined by cylindrical ependymal cells, 

 found in the substance of the epiphysis of an ox. 



Fig. 304. 



-Small Cyst, lined by Cylindrical and Irregularly Shaped 

 Ependymal Cells, in an Epiphysis of Bos taurus. 



Some of the ependymal cells send processes outward towards the periphery. 

 (After Dimitrowa, 1901.) 



Case 2. — Harry P., aged 12, was admitted to hospital in October, 1923, 

 with a history of constant headaches for nearly two years. He had been fitted 

 with various glasses without any benefit. Four months before admission he 

 had his tonsils and adenoids removed, as it was thought that this treatment 

 might alleviate the headaches. 



On Examination. — The patient was thin, and inclined to be irritable. There 

 was no sign of pubertas praecox. The pupils reacted sluggishly to light and 

 accommodation, and there was bilateral papilloedema of 4-5 diopters in each 

 eye. The visual fields were normal. There was complete paresis of upward 

 gaze and some weakness of the right Vlth nerve. The hearing on the right side 

 was somewhat diminished. The other cranial nerves were normal. There was 

 a slight lateral nystagmus to the right. The gait was somewhat ataxic and 

 Romberg's sign was positive. There was very slight weakness of the right 

 arm. All the deep reflexes were normal. 



Radiographs revealed a calcified pineal body and some opening up of the 

 sutures of the skull. After the boy had been in hospital for a week attacks of 

 vomiting and sweating commenced, and it was thought that the condition 

 might possibly be due to a tuberculoma. This diagnosis was supported by the 

 fact that although the boy had a good appetite, he put on no weight and remained 

 exceedingly thin. However, owing to the very definite paresis of upward 

 gaze, it was decided that the more probable diagnosis was that of pinealoma. 



Operation. — Under rectal ether and local anaesthesia a large osteoplastic 



