No acute surface collection, haemorrhage or infarction. No mass effect, space occupying lesion or midline shift. The ventricles and basal cisterns are patent and normal for age. Grey - white matter differentiation is preserved.
There is an ill-defined slightly hypodense mass lesion measuring 20 x 13 mm centred in the left cavernous sinuses extending posteriorly into the pre-pontine cistern and laterally abutting the medial aspect of the left temporal lobe. It appears separate to the pituitary gland. The sella is not enlarged. There is no enlargement of the left superior orbital vein to suggest cavernous sinus thrombosis.
No acute bony abnormality. No orbital pathology detected. Mild mucosal thickening of the right maxillary sinus and sphenoid sinus. The mastoid air cells are clear.
Conclusion
- no haemorrhage or other acute intracranial pathology evident.
- left cavernous sinus mass lesion, which may be responsible for the unequal pupils. Further investigation with post contrast CT advised in the first instance. Differential diagnosis includes a meningioma, giant ICA aneurysm or schwannoma related to the nerves of the cavernous sinus.