Discussion

Pseudotumour cerebri may be idiopathic or secondary. Clinicians must take care to exclude secondary causes of raised intracranial pressure in all patients, but in particular in men, children and women of normal body mass index. This patient was not obese and did not fit the typical phenotype for idiopathic intracranial hypertension; her case highlights the importance of specifically asking about dietary intake and supplements when evaluating a patient with pseudotumour cerebri.

There is a well-documented association between hypervitaminosis A and pseudotumour cerebri: either through supplementation of vitamin A, excessive ingestion of liver rich in vitamin A or synthetic vitamin A derivatives.1 In this case, the only identified association was excess dietary supplement vitamin A intake. There is debate about the level at which acute toxicity can occur; some have reported levels below the recommended daily allowance of vitamin A, and measurement of serum retinol does not correlate with vitamin A status during toxicity.2

In this case, there were hard exudates in the macula between the optic disc and the fovea in a partial star configuration (figure 1A, B). A macular star most frequently occurs in the setting of idiopathic or infective neuroretinitis; but can occur in any case of optic disc swelling, reflecting the severity. Visual acuity measurements in isolation can be misleading in monitoring these cases, as both the macular star and fluid tracking from the optic disc to the macula can degrade the vision, in addition to the optic neuropathy resulting from severe papilloedema. Here, optical coherence tomography helped in monitoring both the disc and the macula and showed the resolution of papilloedema (figure 1G, H).