Damage to the anterior visual pathway and brain parenchyma following external pituitary irradiation

Three cases of damage to the optic nerves and chiasma following pituitary irradiation with Co60 teletherapy are described. All of them presented with progressive visual impairment months following irradiation and simulated recurrence of the tumour. CT scan was also not helpful in differentiating radionecrosis from tumour recurrence. On exploration the optic nerves and chiasma appeared discoloured and scarred. One case, who also had diffuse radionecrosis of brain parenchyma, died. No satisfactory therapy is currently available for this grave complication but proper safeguards can prevent it.