Tract Stars
Damage to this descending tract causes ipsilateral weakness and upper motor neuron signs at and below the level of the lesion.
What is the lateral corticospinal tract (LCST)?
This term is defined as the most caudal segment of the spinal cord with intact, normal sensory and motor function on both the right and left sides.
What is the Neurological Level of Injury (NLI)?
An infarct in the superior division of this highly vulnerable artery often damages the superior optic radiations, causing a contralateral inferior quadrantanopia ("pie on the floor").
What is the Middle Cerebral Artery (MCA)?
The meninges spell "PAD" from the inside out; this innermost layer tightly adheres to the grooves and surface of the brain.
What is the Pia mater?
This reflex stabilizes the eyes on a visual image during head and body movements by utilizing input from the semicircular canals.
What is the Vestibulo-Ocular Reflex (VOR)?
This tract is the exception to the rule of somatotopy, placing the long, "graceful" lower extremities medially and the upper extremities laterally.
What is the dorsal column-medial lemniscus (DCML)?
To establish a motor level at C6, the wrist extensors must score at least a 3, and the elbow flexors at C5 must achieve this specific manual muscle test score.
What is a 5?
These specific types of infarcts occur at the border zones between two different blood supply regions, such as between the ACA and MCA.
What are watershed infarcts?
Cerebrospinal fluid formed in the lateral ventricles must flow through this specific passageway to reach the third ventricle.
What is the Interventricular Foramen of Monro?
Fibers of the inferior optic radiations loop forward through the temporal lobe to form this eponymous anatomical pathway.
What is Meyer's Loop?
This syndrome involves damage to the medial aspects of the DCML, ALS, and LCST, typically causing greater motor impairment in the upper extremities than the lower extremities.
What is Central Cord Syndrome?
This ASIA Impairment Scale (AIS) grade describes a motor incomplete injury where half or more of the key muscles below the NLI have a muscle grade of 3 or greater.
What is AIS D?
A stroke resulting in a left homonymous hemianopsia without other motor deficits most likely indicates an occlusion in this specific cerebral artery.
What is the right Posterior Cerebral Artery (PCA)?
A temporal bone fracture that ruptures the middle meningeal artery will cause blood to pool in the potential space between the skull and the dura, creating this biconvex brain bleed.
What is an epidural hematoma?
These rapid, high-speed eye movements—reaching velocities up to 700 degrees per second—are used to instantly bring targets into central vision.
What are saccades?
This specific artery branches off the aorta to supply the lumbar and sacral cord, leaving the mid-thoracic area (T4-T8) highly vulnerable to infarct.
What is the Great Radicular Artery of Adamkiewicz?
The Zone of Partial Preservation (ZPP) is only applicable in injuries lacking motor or sensory function in these specific lowest sacral segments.
What are S4-S5?
Associated with hypercoagulable states, a thrombosis here obstructs venous drainage, increasing intracranial pressure and decreasing cerebral perfusion.
What is the superior sagittal sinus?
This slow-spreading, crescent-shaped hematoma occurs due to shearing forces tearing the bridging veins as they cross the arachnoid into the dura.
What is a subdural hematoma?
During the pupillary light reflex, the efferent motor signal travels to the ciliary ganglion and pupillary constrictor muscles via this cranial nerve.
What is Cranial Nerve III (Oculomotor)?
In Brown-Séquard Syndrome, damage to the anterolateral system results in this specific sensory loss on the contralateral side below the level of the lesion.
What is the loss of pain and temperature sensation?
When assessing the C8 motor level during the ISNCSCI exam, this is the key muscle action evaluated by the examiner.
What is finger flexion (finger flexors)?
This temporary "browning out" of vision in one eye lasts about 10 minutes and serves as a critical warning sign for ipsilateral internal carotid artery stenosis.
What is amaurosis fugax?
This meningeal fold of the dura mater dips inward, taking the shape of a sickle to separate the two cerebral hemispheres.
What is the falx cerebri?
During the pupillary light reflex, information travels from the pretectal area to these specific, bilateral parasympathetic neurons in the midbrain before traveling out via Cranial Nerve III.
What are the Edinger-Westphal nuclei?