What is the sole cranial nerve that emerges from the dorsal aspect of the brainstem______________?
Show answer Hide answer
Answer: A. Trochlear
Explanation
The trochlear nerve is the sole cranial nerve emerging from the dorsal brainstem. All other cranial nerves emerge from the ventral or lateral aspects of the brain. This unique dorsal exit makes the fourth cranial nerve exceptionally long and thin. Cranial nerves are paired nerves that emerge directly from the brain and brainstem. The trochlear nerve provides motor innervation to the superior oblique muscle of the eye. Brainstem anatomy organizes motor and sensory nuclei in precise columns throughout its length.
Patients with trochlear nerve palsy experience vertical double vision when looking downward. Its long intracranial path makes the trochlear nerve vulnerable to trauma and increased pressure. Neurologists test eye movements to evaluate the structural integrity of this cranial nerve. The oculomotor nerve emerges from the ventral aspect of the midbrain region. The vagus nerve emerges from the ventrolateral sulcus of the medulla oblongata. The abducent nerve emerges from the ventral border between pons and medulla.
Related questions
Q1. Pressure applied to the jaw angle while maintaining airway patency puts which nerve at risk of injury_____________?
Show answer Hide answer
Answer: B. 7th
Firm pressure applied to the jaw angle during airway maneuvers can compress the facial nerve. The facial nerve runs superficially near the stylomastoid foramen right behind the posterior jaw ramus. Compressive forces at...
Q2. During embryonic development, neural tube closure takes place on___________?
Show answer Hide answer
Answer: A. 18 to 23 days post fertilization and is the second stage of craiofacial development
Neural tube closure takes place between 18 and 23 days post-fertilization. This crucial developmental event represents the second stage of craniofacial development. Failure of proper closure results in severe congenital...
Q3. The occipital artery arises as a branch originating from _________________?
Show answer Hide answer
Answer: B. Posterior branch of External carotid
The occipital artery branches directly from the posterior aspect of external carotid. This vessel courses superiorly and posteriorly toward the back of the head. It supplies oxygenated blood to the deep muscles and skin...
Q4. The mental spines on the mandible provide insertion sites for_____________?
Show answer Hide answer
Answer: A. Genioglossus
The superior mental spines on the mandible provide direct insertion sites for the genioglossus muscles. These small bony prominences are located near the midline on the posterior mandibular surface. This secure attachmen...
Q5. The ophthalmic artery branches off from_________________?
Show answer Hide answer
Answer: C. ICA
The ophthalmic artery is the first major branch arising from the internal carotid artery. This branch originates immediately after the internal carotid artery emerges into the cranial cavity. Anatomical tracking shows th...
Q6. The ophthalmic artery branches from the _________ part of the internal carotid artery ?
Show answer Hide answer
Answer: C. Inracerebral
The ophthalmic artery is the first major branch of the internal carotid artery, typically originating as it emerges from the cavernous sinus.