Alternating hemiplegia is best described as

Alternating hemiplegia is a neurological deficit involving limbs on one side and cranial nerves on the opposite side. This is most often related to cranial nerves III, VI, and XII. Although the involvement of the body may be the same, if the lesion is in the midbrain the eye is affected; if it is located in the pons specifically, the lateral rectus muscle is involved; and if the lesion is located in the medulla, the tongue is affected. Ref - Harrison's principles of internal medicine 20e pg 2071