[Reversal of vision metamorphopsia as a manifestation of cerebellar infarct]

Reversal of vision metamorphopsia is a disorder affecting the visuospatial perception of objects, without any changes in their shape, size or colour. It generally involves a full 180 degrees rotation of the visual field in the coronal plane. Its chief causation is vertebrobasilar ischaemia, although the phenomenon has also been linked to many other conditions, such as multiple sclerosis, epilepsy, migraine or traumatic head and neck injuries. Some notable features of reversal of vision metamorphopsia are the wide topographic variety of the lesions responsible for the condition, the transient nature of the symptom and its improvement or resolution in the presence of certain stimuli.

A 35-year-old male with a sudden episode of instability that prevented him from walking, together with vomiting and reversal of vision metamorphopsia that lasted for an hour. A magnetic resonance scan enabled us to identify an acute ischaemic cerebellar lesion as the cause of the condition.

The variety of locations of the lesions that give rise to reversal of vision metamorphopsia would be mainly due to the multisensory nature of the neurons in the posterior parietal cortex, the area of the brain where the visuospatial integration of images is performed. These neurons receive visual, proprioceptive and vestibular afferences, which means that any lesions that occur in these three systems or in the central integrator itself could cause the phenomenon of reversal of vision metamorphopsia.