INSTRUCTION
Examine this patient's eyes.
Examine this patient's visual fields.
SALIENT FEATURES
History
· Insidious onset of defects in visual field. Involvement of the macula is late and is associated with abrupt visual failure as the
presenting feature.
· Hypogonadism (may precede the visual failure by many years): males have impotence and females have amenorrhoea.
Examination
· Bitemporal hemianopia, which is caused by a median lesion of the optic chiasma.
Proceed as follows:
· Examine the hands and face for acromegaly.
· Tell the examiner that you would like to look for signs of hypopituitarism (see pp 375-7). The probable causes are as follows:
-Pituitary tumour (endocrine symptoms precede the visual symptoms; the upper
temporal fields are affected first and then the defect spreads down).
-Craniopharyngioma (bitemporal hemianopia is initially worse in the lower
quadrants).
- Suprasellar meningioma.
- Aneurysms.
- Metastases.
- Glioma.
DIAGNOSIS
This patient has bitemporal hemianopia (lesion) and I would like to investigate for a median mass lesion compressing the optic
chiasma.
QUESTIONS
How would you investigate this patient?
· Formal field testing - perimetry. · Serum prolactin.
· Skull radiography (calcification of craniopharyngioma and size of the pituitary fossa which is best seen in the lateral skull
radiograph).
· CT head scan.