In 1975, Peterson ([1]) wrote an article on the hazards of myelography, published in the journal Radiology.

He stated:

"Air is completely absorbed without producing long-term side effects. Lipiodol and Pantopaque are not absorbed and residual medium in the spinal canal can cause arachnoiditis."

Furthermore, a case report of chronic arachnoiditis after Pantopaque study of the posterior fossa was published by Mortara and Brooks. ([2])

Unknown authors contributed a letter in the British Medical Journal on hyperthyroidism after use of contrast medium. ([3])

Ironically, 1975 also saw the publication of a paper on the use of myelography to diagnose the very condition it causes! Jorgensen et al. ([4]) published a classification of the myelographic appearance of arachnoiditis, which was to be used by many clinicians subsequently.

They divided the condition into two Types, I, the

"empty thecal sac"

and 2,

"localised or diffuse filling defects".

The authors noted:

"The assumed cause of arachnoiditis was, in more than half of the cases, the combination of myelography and operation in close relation."