EYE PROBLEMS
Orbital
metastases occur most commonly in carcinoma of the breast
and malignant melanoma.
They cause:
Visual loss
occurs only if a choroidal deposit bleeds into the eye. Early
radiotherapy, usually 3,000 cGy over 10 days, is indicated to
prevent permanent visual loss in patients with carcinoma of
the breast who have a reasonable prognosis.
Double
vision (diplopia) can occur with raised intracranial
pressure (due to pressure on the sixth cranial nerve) or with
metastases, to the base of the skull (most commonly seen with
carcinoma of the breast). High dose steroids and/or
radiotherapy to the base of the skull can be helpful.
Meanwhile, wearing a patch over one eye relieves the double
vision.
Field
defects are caused by tumor damage to the optical pathways
in the optic nerves or brain. The defect is most often
hemianopsia (loss of peripheral vision on one side only). The
patient’s central vision is normal but loss of peripheral
vision can reduce independence and mobility. The patient may
fail to notice the defect for some time. Some patients need
reassurance that they will not go blind.
Blurred
vision can be due to anti-cholinergic drugs (tricyclics,
scopolamine, atropine). Occasionally patients on morphine
notice intermittent blurring – consider reducing the dose.
Poor
vision can add to a patient’s problems.
Consider:
Dry eyes
can occur if the eyelids do not close properly (for
example, due to a seventh nerve lesion). Use artificial tears (hypomellose
drops) or close the eyelid with hypoallergenic paper tape or
even a tarsorrhaphy.
The author and publisher have taken
precautions to ensure that the information in this book is
error-free. However, readers must be guided by their own
personal and professional standards of good practice in
evaluating and applying recommendations made herein. The
contents of this book represent the views and experience of
the author, and not necessarily those of the publisher.
