Calcification in Intracranial Gliomata

The incidence and diagnostic significance of intracranial calcification detectable by radiography have long been in dispute. The value of calcium in helping to distinguish between tumours of different type, and between neoplastic and non-neoplastic lesions, has never been defined. The present study is concerned with only one group of these conditions, namely the gliomata, and the purpose of this paper is to examine from a radiological point of view the occurrence of calcification within them. “Brain-calculi” and other intracerebral collections of bone and calcium were known to the ancients, but the scientific observation of intracranial calcification dates back no more than a century to the studies of Rokitansky and Virchow. Calcium deposits in the brain—zellenincrustation—were known to Rokitansky (1856) who thought that they were displaced myelin; Virchow was able to prove their mineral nature by biochemical means. He demonstrated their predilection for the walls of blood vessels, and named the tubular calcospherites that he isolated sandkoerper. Sporadic case reports of calcified intracerebral tumours appeared throughout the late 19th-century literature: Storch in 1899 described a calcified ependymoma in a six-year-old child, and Saxer some years later emphasised the occurrence of calcification in these tumours. The first calcified glial tumour to be demonstrated by X-ray was probably that of Grumach, who in 1907 described a patient that he had seen in 1898 in Berlin with features suggestive of a cerebral tumour (Grumach, 1907).