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Ocular signs of chordomas.

My interest in chordomas dates from 1954 when an agitated woman in her late 30s consulted me because she thought she was going blind. Severe headache and the recent onset of diplopia confirmed her worst suspicions. On examination she was found to have a right lateral rectus palsy and bitemporal hemianopia. I assured her that her vision would probably improve after cranial surgery, as indeed it did, and that all would then be well, an optimistic prognosis which proved profoundly mistaken. Patients with chordomas rarely do well. Skull X-rays revealed an intrasellar tumour with a calcified suprasellar extension. Craniotomy revealed a chordoma which was removed as far as possible. This was followed by deep ray therapy. By 1958 the VI nerve palsy was complete and permanent, by 1962 the nasopharynx was involved, by 1964 the palate was ulcerated and required surgical excavation. In 1967 she died after suffering multiple cranial nerve palsies and the nightmare of persistent pain. Chordomas arise from embryonic rests of the notochord the primitive axial skeleton of vertebrates. Extending from head to tail of the embryo it becomes enclosed within a cartilaginous cover except in certain areas. One of them is the dorsum selle; another is the sacrococcygeal region and these are the sites of election of chordomas. Virchow (1857) first described an intracranial chordoma arising from the dorsum sellae or clivus in the region of the spheno-occipital synchondrosis. He thought it arose from cartilage but Muller (1858) recognized its true origin from the notochord and Ribbert (1894) put the matter beyond reasonable doubt by producing experimental tumours in the rabbit from the nucleus pulposus of intravertebral cartilages and these tumours were composed of vacuolated or physaliferous cells identical with those ofthe notochord. Clivus chordomas are nodular firm eminences which exhibit slow expansile growth with infiltration and destruction of bone. They do not usually invade soft tissues but frequently recur after excision. They rarely metastasize. If we look at a chordoma in saggital section we see that the symptoms and signs likely to arise from such a growth depend on the site of origin and the direction in which it spreads.