Ocular findings in head injuries and trauma Mariela Reyes, UAG-SOM
It is estimated that around 3 million people are involved in non-fatal injuries in the United States alone. These injuries have been associated with multiple presentations of eye trauma varying from severity depending on location and mechanism of injury. According to CDC, men are involved more than females representing 66% of eye trauma visits in the ED (2019) and 91% represent people younger than the age of 60. Eye trauma is considered a seasonal condition with a peak incidence between the months of May-July. The mechanism of injury trends by age groups affecting mostly young children, young adults and elderly. Young individuals are associated with a higher incidence for motor vehicle accidents and elderly with falls. Consequently, there are 13.5 million individuals living with disabilities in the United States. Traumatic brain injury (TBI) lesions include skull fractures, herniation and compression following increased intracranial pressure. The types of injury are classified as primary (external forces) and secondary (internal). The displacement and compression of structures leads to varying clinical presentation and degree of severity. Cranial nerve involvement accounts pupillary asymmetry (CN III) and lateral rectus palsy (CN VI). The abducens nerve is the most susceptible nerve due to its long pathway arising from nucleus abducens in the pons. Ophthalmologic findings can be classified as intra ocular, extra ocular or orbital fractures. Intra ocular includes optic nerve/ pupillary involvement, papilledema, macular edema, vitreous/ retinal hemorrhage, corneal or scleral tears and hyphema. Vitreous hemorrhage refers to the leakage of blood into the vitreous chamber, leading to vision loss. Mechanism of hemorrhage can be due to blunt trauma (ruptured vessel), abnormal vessel or subarachnoid hemorrhage (Terson syndrome) that can cause retinal tear or detachment. Further evaluation is required for children as it may indicate abusive head trauma. Hyphema is a painful collection of blood in the anterior chamber of the eye (between the cornea and iris) causing partial or complete vision blockage. Papilledema is caused by swelling of the optic nerve due to increased intracranial pressure. Management of traumatic hyphema is focused on preventing further hemorrhage and managing or decreasing intraocular hypertension (> 50 mmHg for 5 days), depending on the severity and extent. Activity should be limited for a minimum of 1 week. Eye shield- should use at all times for a minimum of 1 week (or until resolved) to prevent potential damage to the affected eye as “ambient light” has been associated to damage to endothelium due to the interaction with porphyrins (anterior chamber). Pain may be managed with cycloplegic topical drops (Cyclopentolate 1% tid or Scopolamine 0.25% bid). Oral analgesics (NSAIDs) are recommended for those that do not tolerate cycloplegic drops. Glucocorticoids eye drops (prednisolone acetate 1% or dexamethasone sodium phosphate 0.1% qid). Sickle cell status should be determined to avoid complications such as rebleeding. If so, hospitalization is warranted. For IO HTN ʹ acetozolamide (5mg/ kg per dose qid) and methazolamide (2.5 mg/kg per dose qid). IV mannitol (1.5 g/ kg over 45 min bid) is recommended for uncontrolled IO HTN. Lastly, surgical clot evacuation if persistent. References Motor Vehicle CDC Injury Traumatic brain injury: Epidemiology, classification, and pathophysiology ʹ UpToDate Traumatic hyphema: Management ʹ UpToDate Traumatic Oculomotor Nerve Palsy