Resident’s Day Submission Nicole West, O.D. Brain Injury Vision Rehabilitation Optometry Resident University of Houston College of Optometry

Title: Cranial nerve III palsy in a child following a penetrating arrow to the head

Abstract: This case examines the unique presentation of a symptomatic cranial nerve III palsy in a child after sustaining an arrow to the head. Management of diplopia in children and amblyopia prevention will be discussed.

I. Case History • 7 year old, Caucasian Male • Chief Complaint: § Patient presents to assess the progress of a left homonymous hemianopsia and constant diplopia secondary to a right cranial nerve III palsy (CN III) after sustaining a penetrating injury with an arrow to the head on 04/11/15. § Patient is wearing glasses full-time and alternating a Patch Works patch equally between the eyes for diplopia relief as instructed at his last visit. • Ocular History § First eye exam (06/15/2015). § Constant, binocular diplopia secondary to a complete cranial nerve III palsy of the right eye caused by traumatic brain injury (TBI). • 35 prism diopter constant, right exotropia • Restricted EOM OD • Fixed pupil OD • Mild ptosis of upper eyelid OD • Reduced accommodation OD § Complete left homonymous hemianopsia secondary to TBI • Medical History: § The patient suffered a penetrating traumatic brain injury from an arrow to his right temporal lobe on 4/11/15, causing bilateral parenchymal contusions to his temporal lobes, as well as, intraventricular and subarachnoid hemorrhages. He was reported to have lost consciousness at the scene, but recovered shortly after. He has undergone multiple subsequent surgeries for sequelae of the accident, including craniectomy and ventriculoperitoneal (VP) shunt placement in the right frontal/temporal lobe. • Medications/Alleriges: § The patient was taking acetaminophen, amantadine, baclofen, clopidogrel, diazepam, ibuprofen, levetiracetam, lisdexamfetamine, magnesium hydroxide, nitrofurantoin, ondansetron, oxycodone, polyethylene glycol, and sertraline. § NKDA • Medical Family History § The family medical history was significant for brain tumor (mother – deceased) as well as mental illness (father). • Social History § The patient is currently living with his aunt (adoptive mother) and siblings. § 1st grade

II. Pertinent Findings • Physical: § Patient presented on a stretcher escorted by paramedics wearing a helmet status-post craniectomy. • Clinical: § Presenting Spectacle Rx from June 2015: OD +2.00 DS, OS +0.50 DS § Aided Distance Visual Acuities: 10/10-1 OD, 10/10 OS § Aided Near Visual Acuities: 20/80 OD, 20/25-1 OS § Hirschberg (cc): OD +1.00 mm, OS 0 mm. § Interpretation: 22 prism diopter constant, right exotropia § Krimsky (cc): 20-25 prism diopter constant, right exotropia § MEM (cc): +1.50 DS OD, +1.25 DS OS § EOM testing revealed severe supraduction gaze restrictions, mild infraduction gaze restrictions, and full abduction/adduction of the right eye. The left eye demonstrated full and smooth range of motion. § Monocular visual field testing from non-seeing to seeing revealed a stable, complete left homonymous hemianopsia. § Visual neglect testing with line bisection revealed moderate left side neglect. § Pupils: § OD: 6mm in light, 7mm in dark; trace direct and consensual response. No APD § OS: 5mm in light, 6mm in dark; 3+ direct and consensual responses. No APD § MRD: 2.5mm OD, 5.0mm OS • Radiology: § Initial Head CT (04/11/15): § Penetrating injury with a hollow metallic object in the right temporal lobe. § Parenchymal contusions in both temporal lobes. § Intraventricular and subarachnoid hemorrhages. § CT Brain (04/12/15): § Blossoming parenchymal contusions in the right temporal lobe with new hemorrhages in the right basal ganglia. § Evolving parenchymal contusion in the left temporal lobe § Stable subarachnoid and intraventricular hemorrhages § Interval decompressive hemicraniectomy § Removal of foreign body § Ventriculostomy placement

III. Differential Diagnosis • Primary/leading diagnosis: § Cranial nerve III palsy • Others § Acquired exotropia § Gaze palsy § Cranial nerve IV palsy § Cranial nerve VI palsy § IV. Diagnosis and Discussion • Causes of third nerve palsy in childhood (Ng and Lyons1) § Congenital 33% § Trauma 28% § Tumor 22% § Vascular 11% § Meningitis 6% § Idiopathic 2% • CN III palsy is uncommon in children and is most commonly congenital or the result of trauma.1,2 • According to a retrospective study by Schumacher-Feero LA and colleagues2, a palsy was complete if no adduction or vertical action of the superior or inferior rectus or the inferior oblique was seen, the pupil was dilated and unresponsive to light, and ptosis was present. A partial palsy was characterized by limited adduction and vertical movements of the globe on ductions, normal or dilated but responsive pupil, and normal or ptotic eyelid. • Traumatic CN III palsies occur most often with the pupil involved.3 • The goals of managing CN III palsy in children are to promote optimal development of visual acuity and binocular function including the management of diplopia and preventing suppression.2 • Children with CN III palsy have a high incidence of amblyopia caused by paresis of the extraocular muscles, dysfunction of the levator palpebrea muscle leading to obstruction of the visual axis, and impairment of accommodation.2 • Reduced accommodation in the affected eye in the presence of underlying hypermetropia is equivalent to penalization of the affected eye.4 • Treatment of amblyopia is effective in maintaining the level of visual acuity present at the onset of the CN III palsy and improvement in acuity is difficult to achieve.2 • CN III palsy may undergo partial resolution in children, but surgical treatment is frequently necessary and multiple procedures are often needed to maintain good ocular alignment.2 • Surgery can result in cosmetically acceptable alignment of the eyes but rarely results in restoration or achievement of binocular function.2 • When CN III palsy is complete or bilateral, achieving satisfactory alignment is more problematic and requires more surgical procedures.2 Often, partial CN III palsies do not require any alignment surgery because of spontaneous resolution or partial recovery. 2

V. Treatment and Management • Assessment: o Improving traumatic cranial nerve III palsy OD § Determined to be “partial” at this visit. • 20-25 prism diopter constant, right exotropia • Dilated, minimally reactive right pupil • Mild ptosis of right eyelid • Reduction of accommodation in the right eye, which improves with refractive correction. • Severe supraduction gaze restrictions, mild infraduction gaze restrictions, and full abduction/adduction of the right eye. Acquired exotropia OD secondary to the CN III palsy OD o Acquired cranial nerve IV palsy OD o Accommodative insufficiency OD secondary to CN III palsy OD and uncorrected refractive error o Hyperopia, anisometropia (OD>OS) o Left homonymous hemianopsia with left neglect secondary to TBI • Treatment specific to this patient: o Continue full-time wear of spectacle Rx and alternating occlusion with Patch Works patch equally between eyes to prevent the onset of amblyopia in either eye. o Family was instructed to cover the right eye when reading or participating in near therapies due to the reduction of accommodation and near acuity. o Consider occlusion foil treatment in the future. § Trialed in previous examination (06/15/2015) but unsuccessful due to patient age/abilities. Occlude inferior portion of right lens, as patient’s right eye cannot accommodate appropriately and occlude superior portion of left lens, making the patient monocular at all distances and thus alleviating diplopia and preventing amblyopia. o Monitor 3 months (due November 2015). § Typical Recommended Treatment: o Management is symptomatic; occlusion with an eye patch may be used if diplopia is significant.5 In young children, alternate day occlusion of each eye will help prevent amblyopia.5 o Prism prescribing can be challenging due to the noncomitant nature of the strabismus; many patients have horizontal and vertical components. The large magnitude Fresnel prism degrades the visual acuity, which in children could cause amblyopia due to the prism inadvertently acting as a graded occluder. However, if the strabismus is stable, somewhat comitant and the patient can gain fusion with prism then ground in prism could be of benefit in restoring binocular vision. o Spectacle correction of hypermetropia and use of bifocal lenses for near can be helpful in cases of underlying hyperopia and reduced accommodation.4 o Clinical experience supports a waiting period of 6-12 months is generally recommended after the onset of CN III palsy before considering surgery with the caveat that the angle of strabismus and EOM function must be stable over several follow-up visits to ensure that neurologic healing is complete. o Patients with CN III palsy secondary to trauma generally undergo a 1-year observation period before surgical correction of ptosis, however, an excessively long waiting period poses a high risk for visual deprivation amblyopia in young children and earlier surgical correction may be warranted.2 o As in Adie’s pupil, symptomatic mydriasis may be treated with pilocarpine 0.1% drops in the affected eye.4 Cosmetic contact lenses with an opaque iris to reduce light may also be beneficial for largely dilated pupils. o Frequent follow-up is recommended, especially for young patients whose vision has not matured.4 VI. Conclusion: • Attention to amblyogenic factors is important in the management of young children with diplopia. • Spectacle correction as well as alternate day occlusion can help prevent amblyopia. • Cranial nerve III palsies may undergo partial recovery or spontaneous resolution but surgical correction is often necessary for cosmesis and rarely results in normal binocular function. • Clinical pearls: § Differentiation between partial and complete cranial nerve palsies can aid in determining prognosis. § Frequent follow-up is important during the first 6-12 months after the onset of the palsy, as this is when most of the spontaneous resolution is expected to take place.

REFERENCES:

1. Ng Ys, Lyons CJ. Oculomotor nerve palsy in childhood. Can J Ophthalmol. 2005; 40(5):645-653. 2. Schumacher-Feero LA, Yoo KW, Solari FM, Biglan AW. Results following treatment of third cranial nerve palsy in children. Trans Am Ophthalmol Soc 1998;96:455-72; discussion 472-4.

3. Kaido T1, Tanaka Y, Kanemoto Y, Katsuragi Y, Okura H. Traumatic oculomotor nerve palsy. J Clin Neurosci 2006 Oct;13(8):852-5.

4. Lyons CJ, Godoy F, ALQahtani E. Cranial nerve palsies in childhood. Eye (Lond). 2015 Feb;29(2):246-51. doi: 10.1038/eye.2014.292. Epub 2015 Jan 9.

5. Hollis GJ. Sixth cranial nerve palsy following closed head injury in a child. J Accid Emerg Med 1997 May;14(3):172-5.