2. When the pressure of the exostosis produces pain which cannot otherwise be relieved.
3. If the exostosis nearly blocks up the meatus of both ears, and there is prospect of each side becoming completely blocked in the near future. Here operation is carried out on the worst side.
4. If the meatus is nearly blocked by the exostosis and the patient going to a country where he cannot be within easy reach of a competent medical man.
The indications for operation in the case of a frontal exostosis are as follows:—
1. When the exostosis interferes with the actions of the ocular muscles, causes proptosis and threatens the integrity of the globe.
2. When associated with pain which cannot otherwise be relieved.
3. When the exostosis leads to blockage of the accessory sinuses of the nose, more especially when such blockage is associated with pus pent up within.
4. When very unsightly.
The accompanying [figure] illustrates the deformity and dangers associated with large frontal exostoses. The tumour developed from the inner angle of the orbital cavity, pushing the globe forwards and outwards, with diplopia and severe neuralgia.
It is barely possible to enter into the operative details suited to frontal and aural exostoses—the operations are so atypical. It is sufficient to say that the operation may be a very formidable one, that the details must be carefully thought out, and that every precaution must be adopted to avoid injuring neighbouring structures.