The Surgery of the Skull and Brain

by Louis Bathe Rawling

Secondary sarcomata and carcinomata.

OSTEOMATA

Exostoses of the skull, though by no means of frequent occurrence, occupy such definite positions that it would appear as if they were dependent on some local governing cause. They develop most frequently in the following positions:—

At the external angular frontal process.

At the frontal and parietal eminences.

In the region of the frontal sinus.

In the region of the external auditory meatus and mastoid process.

All pathological museums possess specimens illustrating the formation of such exostoses, tumours of a like nature in other parts of the skull being excessively rare.

In endeavouring to arrive at an explanation it would appear necessary to direct one’s attention to tumours of a similar nature occurring in other parts of the body, more especially in the long bones. There, it is well recognized that their development is dependent on irregularities of growth in the region of the epiphyseal lines, regions where activity of growth is long maintained.

On referring again to the skull, similar features appear. For instance, the frontal bone, besides possessing one primary centre for the frontal eminence, has secondary centres for the external angular frontal process, for the trochlear fossa, and for the nasal spine, and it is highly probable that those exostoses which develop in the region of the frontal sinus in reality arise from one or other of the secondary centres situated in that region.