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.