Traumatic injuries to the oculomotor nerve

PURPOSE OF THE STUDY: A collective summary of the pathogenesis, character and clinical significance of damage to the oculomuscular innervation, arising from closed head trauma, based on our own clinical observations, together with a review of literature on the topic. MATERIALS AND METHODS: The clinical and pathophysiological evaluation of injuries to the oculomotor (III) nerve based on a prospective study in our clinic, dating from 1994 onwards: the clinical material consisted of 600 patients admitted to our Department of Neurosurgery following head trauma, the subgroup consisted of 38 patients, who died following major head trauma. RESULTS: Few authors focus on damage to the innervation of oculomotor muscles, the diagnosis of damage being difficult due to the usually poor clinical condition of such patients, the interdisciplinary nature of the resulting damage, and their delayed ophthalmological evaluation. The oculomotor (III) nerve is the nerve most frequently damaged amongst the cranial nerves, taking into account the innervation of the ocular system nerves (II-VII). Of clinical importance is differentiating between the mechanism of damage, paying particular attention to intracranial damage. The mechanisms of damage can be distinguished by: 1) partial tearing of the parasympathetic fibres contused against the petroclinoid ligament, 2) total tearing of the parasympathetic nerve root, 3) complete tear of one or both oculomotor nerves at the interpeduncular base, 4) nerve root tear, resulting from vessel perforation. The oculomotor nerve has the ability to regenerate. The regenerative process should occur within 3 to 5 months, that is without pathological synkinesis. If this process prolongs, this may lead to unpleasant consequences, such as the "misdirection phenomenon". CONCLUSIONS: Primary damage to the oculomuscular innervation resulting from closed head trauma is an integral component of such conditions. Early diagnosis and neuroprotective therapy may prevent pathological regeneration.