PPOM 1 Week 1 (LEC 2-13)

NGL Lectures 8 and 9 were a struggle to make cards for, couldn't tell you what was going on half the time...

(2) Neurulation occurs at _____ of development.

Weeks 3-4

(2) Neurulation

Process in which notochord induces overlying ectoderm to develop into the neural plate, then the midline of the neural plate folds inward, creating a neural groove, with a neural fold on either side. Finally, neural groove becomes neural tube and neural folds become neural crest cells.

(2) The neural tube eventually develops into the:

spinal cord and brain (CNS)

(2) The neural crest cells eventually develop into the:

PNS (eg sensory cell bodies) and other cells (eg melanocytes, odontoblasts, laryngeal cartilage)

(2) The Ectoderm overlying the neural tube eventually develops into the:

skin, musculature, parts of vertebrae or skull

(2) The neural groove eventually develops into the:

neural tube

(2) The neural folds (edge of neural groove) eventually develop into the:

neural crest cells

(2) Spina Bifida

Medical Condition in which there is a failure of the caudal neuropore to close

(2) Encephalocele (cranium bifidum)

Medical Condition in which there is a failure of the rostral neuropore to close, causing a herniation of cranial contents (most common in occipital region)

(2) Anencephaly

Medical condition in which there is a complete failure of the brain and overlying bones of the skull to form

(2) The Marginal Layer of the neural tube becomes the:

white matter

(2) The Mantle Layer of the neural tube becomes the:

gray matter, basal and alar plates, motor cell bodies

(2) The Ventricular Layer (aka Neuroepithelial Layer) of the neural tube becomes the:

ependymal (glial) cells

(2) The Neural Canal of the neural tube becomes the:

ventricles and central canal

(2) The Cranial neural crest contributes to the:

craniofacial skeleton, cranial ganglia, teeth, thyroid cells

(2) The Vagal neural crest contributes to the:

enteric ganglia, smooth muscle cells, cardiac septa

(2) The Trunk neural crest contributes to the:

dorsal root ganglia, sympathetic ganglia, adrenal medulla

(2) The Sacral neural crest contributes to the:

enteric ganglia, sympathetic ganglia

(2) The dorsal portion of the neural tube becomes the:

sensory neurons

(2) The ventral portion of the neural tube becomes the:

motor neurons

(2) Tethered Cord Syndrome

Medical condition in which the spinal cord can be attached to surrounding tissue, which stretches the spinal cord during growth

(2) The Forebrain vesicle (prosencephalon) becomes the:

telencephalon and diencephalon

(2) The Midbrain vesicle (mesencephalon) becomes the:

mesencephalon

(2) The Hindbrain vesicle (rhombencephalon) becomes the:

metencephalon and myelencephalon

(2) The walls of the telencephalon becomes the:

cerebral hemispheres

(2) The cavities of the telencephalon becomes the:

lateral ventricles

(2) The walls of the diencephalon becomes the:

thalamus

(2) The cavities of the diencephalon becomes the:

third ventricle

(2) The walls of the mesencephalon becomes the:

midbrain

(2) The cavities of the mesencephalon becomes the:

cerebral aqueduct

(2) The walls of the metencephalon becomes the:

pons, cerebellum

(2) The cavities of the metencephalon becomes the:

upper part of fourth ventricle

(2) The walls of the myelencephalon becomes the:

medulla oblongata

(2) The cavities of the myelencephalon becomes the:

lower part of fourth ventricle

(2) CN I (Olfactory) comes from the:

Telencephalon

(2) CN II (Optic) comes from the:

Diencephalon

(2) CN III (Oculomotor) and CN IV (Trochlear) come from the:

Mesencephalon

(2) CN V (Trigeminal), CN VI (Abducens), CN VII (Facial), and CN VIII (Vestibulocochlear) come from the:

Pons

(2) CN IX (Glossopharyngeal), CN X (Vagus), CN XI (Spinal Accessory), and CN XII (Hypoglossal) come from the:

medulla oblongata

(2) Holoprosencephaly

Medical condition in which there is complete or partial failure of the prosencephalon (forebrain) to divide along midline (no separate left and right hemispheres, no separate lateral ventricles)

(2) Dandy-Walker Syndrome

Medical condition in which cerebellar vermis does not grow properly from rhombic lip (due to either agenesis or hypoplasia) causing cystic dilation of fourth ventricle (increased CSF, hydrocephalus)

(2) Fetal Development

Process of neuroblasts migrating and producing neurons and increasing the size of the cerebrum

(2) Microcephaly

Medical condition in which reduction in neurogenesis occurs. The lack of growth in the brain means the overlying bones of the calvaria also grow slowly

(2) Choroid Plexus

Cells that produce CSF

(2) Hydrocephalus

Medical condition in which ventricular system is not entirely open leading to lack of CSF flow/abnormal accumulation of CSF within the ventricles of the brain

(2) Ventricle

network of fluid-filled cavities that help keep the brain buoyant and cushioned

(3) The Blood-brain barrier is formed by:

endothelial cells that form the walls of the capillaries

(3) The Blood-CSF barrier is formed by:

epithelial cells of the choroid plexus facing the cerebrospinal fluid

(3) The Arachnoid barrier is formed by:

avascular arachnoid epithelium, underlying the dura, and completely enclosing the CNS

(3) Blood Brain Barrier

A selective semipermeable membrane between the blood and the interstitium of the brain

(3) Major structures of the BBB

endothelial cells (ECs), pericytes (PCs), astrocyte end-feet

(3) Tight Junction (Zona Occludens)

Part of BBB located between cerebral endothelial cells that form and maintain tight junctions by connecting the Occludin and Claudin transmembrane proteins to the cytoskeleton

(3) Scalp

skin and subcutaneous tissue covering the neurocranium

(3) Skull

composed of flat bones, with cortical bone forming the outer and inner tables and spongy bone creating the middle diploe layer

(3) Meninges

three layers of membrane that envelop the brain and spinal cord

(3) Dura Mater

2 layers of dense connective tissue that adheres to the inner surface of the skull and vertebrae

(3) Arachnoid Mater

Thin, wispy membrane that lies just deep to the dura and is superficial to the pia mater

(3) Pia Mater

very thin, clear membrane that directly adheres to the surface of the brain and spinal cord

(3) Epidural Space

Potential space between the inner skull and dura mater

(3) Subdural Space

Potential space between dura mater and arachnoid mater

(3) Subarachnoid Space

Potential space between arachnoid mater and pia mater

(3) Vasculature of Epidural Space

Middle meningeal artery

(3) Vasculature of Subdural Space

bridging veins

(3) Falx cerebri

Sickle-shaped Dural fold formed by the meningeal dura mater

(3) Tentorium Cerebelli

Dural fold that forms a horizontal partition between the cerebrum and cerebellum

(3) Brain Herniation

Medical condition in which something inside the skull produces pressure that moves brain tissues

(3) An Epidural Hematoma occurs when:

Middle meningeal artery is injured due to trauma

(3) A Subdural Hematoma occurs when:

tearing of the bridging veins occurs

(3) A Subarachnoid Hemorrhage occurs when:

aneurysm rupture between arachnoid mater and pia mater occurs

(3) Transtentorial (Uncal) Herniation

Uncus (Medial portion of temporal lobe) herniates downward through the tentorium cerebelli and compresses the ipsilateral oculomotor nerve; “blown pupil”

(3) Transforaminal (Tonsillar) Herniation

The cerebellar tonsils herniate down through the foramen magnum, causing compression of the brainstem and medulla oblongata, disrupting vital functions such as respiration and cardiovascular regulation

(3) Subfalcine (Cingulate) Herniation

The cingulate gyrus herniates down below the falx cerebri. Most common type of herniation

(3) Meningioma

Medical condition in which most common primary brain tumor occurs; benign, well-circumscribed, slow-growing tumors that arise from the meninges (arachnoid layer)

(3) Meningitis

Medical condition in which inflammation of the pia-arachnoid layer (leptomeninges) of the brain, spinal cord, or both occurs. Can be Bacterial/Viral/Fungal

(3) Ventricular system

network of interconnected cavities in the brain, filled with cerebrospinal fluid (CSF), which cushions the brain, removes waste, and maintains intracranial pressure

(3) The Lateral Ventricles are located:

in each cerebral hemisphere

(3) The Third ventricle is located:

in the diencephalon, between the 2 thalami and part of hypothalamus

(3) The 4th ventricle is located:

in the hindbrain, situated between the brainstem and cerebellum

(3) Cerebrospinal fluid (CSF)

surrounds the brain and spinal cord, and may function as a shock absorber for the CNS

(3) Choroid plexus tumors

Medical condition in which rare benign tumors (papilloma) occurs, can both obstruct flow of CSF and overproduce CSF

(3) Intraventricular hemorrhage

Medical condition which can result from extension of intracerebral hemorrhage or trauma, commonly seen in preterm infants

(3) Ventriculitis

Medical condition in which Inflammation of the ependymal lining of the cerebral ventricles occurs, usually secondary to an infection such as posttraumatic or implant-related meningitis

(3) Circumventricular Organs

Areas in which BBB is not present (Median eminence, Posterior pituitary, Pineal gland, Subfornical organ, Organum vasculosum of the lamina terminalis, Area postrema)

(3) Area postrema

Structure in the caudal medulla with the role of detecting blood-borne emetic agents

(3) Obstructive hydrocephalus

Medical condition in which there is a mechanical obstruction (usually to Sylvian Duct) of the flow of CSF through ventricular system

(3) Communicating hydrocephalus

Medical condition in which there is problem blocking the reabsorption of CSF from the Subarachnoid space into venous system

(3) Hydrocephalus ex vacuo

Medical condition in which an expansion of the ventricles due to tissue loss

(4) CT scan

Helical x-ray beams are directed through the brain, head, neck; 2D cross sectional images are compiled, and images may be integrated for a 3D view

(4) Conventional Angiogram

Fluoroscopy-guided imaging of a vessel of interest by accessing a peripheral vein or artery via catheterization and using intravenous contrast

(4) Magnetic Resonance Imaging (MRI)

Magnetic excitation causes changes in alignment of atoms within the body

(4) Carotid Ultrasound

Cross-sectional imaging of the cervical segments of the major vessels to the head. Arteries evaluated on a standard duplex ultrasound (e.g. Common carotid, Internal carotid (cervical segments only), External carotid, Vertebral (cervical))

(4) CT scan Indications

Emergencies (Trauma, Stroke, Syncope, Altered mental status), Characterize tumors

(4) CT scan Contraindications/Risks

Radiation, must weigh risks and benefits in pregnancy and children, Difficult to quantify risk of low dose ionizing radiation on humans

(4) Brain MRI Indications

Early stroke (<12hrs), Visualization of cranial nerves

(4) MRI Contraindications/Risks

Claustrophobia, Metal implants (pacemaker, old prosthetic heart valves), Costly, Weight limit 350 lbs

(4) Carotid Ultrasound Indications

Suspicion of, or to follow–up a known carotid or vertebral artery stenosis (Common Clinical Presentations:

(4) Carotid Ultrasound Disadvantages

Technician-dependent, Image degradation

(4) Conventional Angiogram Indications

Stenosis with intention to treat, Traumatic vascular injury, Aneurysm, arteriovenous malformation

(4) Conventional Angiogram Disadvantages

Most expensive, Invasive, limited to visualization of vasculature and clinicians often need additional cross sectional imaging to observe how pathology relates to surrounding organs

(4) CT IV Contrast

iodinated solution administered to highlight various tissues via three routes: intravenous, oral, rectal