Which risk factor for traumatic brain injury (TBI) should a nurse include in a discussion about prevention for a group of adolescents?

Choice a reason:
The inability of the eye to look outward, known as lateral rectus palsy, is associated with cranial nerve VI, the abducens nerve, not the oculomotor nerve. The oculomotor nerve does not control the lateral rectus muscle which governs this movement.

Choice b reason:
Myopia, or nearsightedness, is a refractive error of the eye where distant objects appear blurry while close objects can be seen clearly. It is not related to oculomotor nerve paralysis, which affects eye movements and pupil response, not the shape of the eyeball or the refractive properties of the lens.

Choice c reason:
Ptosis, or drooping of the upper eyelid, and an absence of pupillary constriction are classic signs of oculomotor nerve paralysis. The oculomotor nerve controls most of the eye's movements, including lifting the eyelid via the levator palpebrae superioris muscle and constricting the pupil through the circular muscles of the iris.

Choice d reason:
Normal eye movement would not be expected in a patient with oculomotor nerve paralysis. This nerve controls the majority of the eye's movements, so paralysis would lead to abnormal eye movement, such as the inability to move the eye upward, downward, or inward.

Choice A reason:
Peripheral vision is the ability to see objects and movement outside of the direct line of vision. This type of vision is assessed using different methods, such as confrontation visual field testing, where the examiner moves objects into the patient's side vision from different angles. Standing 20 feet away from a chart would not be the appropriate method to assess peripheral vision.
Choice B reason:
The assessment of external eye structures involves examining the physical appearance and condition of the eyelids, sclera, conjunctiva, and surrounding areas. This is typically done at a close range and does not require the patient to stand at a distance from a chart. The nurse would inspect these structures directly, often with the aid of a penlight for better visibility.

Choice C reason:
Distant vision is the ability to see objects far away, and it is what the nurse is preparing to assess when the client is asked to stand 20 feet from a chart. This distance is standard for the Snellen eye chart, which is used to measure visual acuity. The chart has rows of letters that decrease in size, and the patient is asked to read the smallest line of letters they can see clearly. The Snellen chart is the most common method used by eye doctors to measure visual acuity.
Choice D reason:
Near vision is the ability to see objects that are close to the eyes clearly. It is assessed using different charts, such as the Jaeger eye chart, which contains blocks of text in various type sizes. The patient is asked to read the text at a close range, typically around 14 inches, not 20 feet. Therefore, standing 20 feet away from a chart would not be the method to assess near vision.