thalamic haemorrhage
Last reviewed 01/2018
Thalamic haemorrhage is usually caused by hypertension. It is associated with contralateral hemisensory loss, ataxia and minor motor weakness.
Oculomotor abnormalities include loss of vertical gaze, especially upwards; deviation downwards and inwards of the eyes at rest; hyperadduction with poor abduction in one or both eyes; and conjugate eye deviation to the side opposite the lesion or ipsilateral lesion.
Behavioural abnormalities are common. They include diminished alertness, apathy, amnesia and a reduced ability to remember new events. There may be aphasia from non-dominant hemispheric lesions. Visual neglect is rare.
Oculomotor and behavioural abnormalities are characteristic of medial thalamic involvement; sensory and ataxic abnormalities suggest ventrolateral thalamic structures. Extension into the subthalamic nucleus is suggested by hemiballismus.