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Studied by 12 people
Neurology Flashcards
Nervous System Anatomy and Overview
Objectives:
Review the anatomy of the nervous system.
Understand the pathology and surgical procedures related to the nervous system.
Learn how vascular issues affect the nervous system.
Understand diagnostic procedures used in neurology.
Human Nervous System
Central Nervous System (CNS):
Brain
Spinal Cord
Peripheral Nervous System (PNS):
Sympathetic Nerves:
Dilate pupils.
Inhibit salivation.
Relax airways.
Increase heartbeat.
Inhibit activity of the stomach.
Stimulate release of glucose.
Inhibit gallbladder.
Secrete epinephrine and norepinephrine.
Relax bladder.
Promote ejaculation and vaginal contractions.
Parasympathetic Nerves:
Constrict pupils.
Stimulate salivation.
Constrict airways.
Slow heartbeat.
Stimulate activity of the stomach.
Inhibit release of glucose.
Stimulate gallbladder.
Stimulate activity of intestines.
Inhibit activity of intestines.
Contract bladder.
Promote erection of genitals.
Anatomical Structures:
Pia mater
Arachnoid membrane
Dura mater
Lateral ventricle with choroid plexus
Massa intermedia
Corpus callosum
Interventricular foramen (Monro)
Hypothalamus
Pituitary body
Sella turcica
Foramen of Luschka
Medulla oblongata
Spinal cord
Skull
Scalp
Superior longitudinal sinus (sagittal sinus)
Intracranial subarachnoid space
Third ventricle with choroid plexus
Pacchionian granulation
Aqueduct of Sylvius
Cerebrum
Tentorium cerebelli
Midbrain
Pons
Cerebellum
Transverse sinus
Fourth ventricle with choroid plexus
Cisterna magna
Foramen of Magendie
Spinal subarachnoid space
Sympathetic Chain (C6, C7, C8, T1-T12, L1-L5, S1-S5, Co1)
Nerves
Nerves are whitish fibers or bundles of fibers that transmit impulses of sensation to the brain or spinal cord and impulses from these to the muscles and organs.
Cranial Nerves:
Olfactory nerve (CN I)
Optic nerve (CN II)
Oculomotor nerve (CN III)
Trochlear nerve (CN IV)
Trigeminal nerve (CN V)
Abducens nerve (CN VI)
Facial nerve (CN VII)
Vestibulocochlear nerve (CN VIII)
Glossopharyngeal nerve (CN IX)
Vagus nerve (CN X)
Accessory nerve (CN XI)
Hypoglossal nerve (CN XII)
Brain
The skull protects the brain.
Cerebrospinal Fluid (CSF): Clear, colorless, watery liquid that surrounds and protects the brain and spinal cord of vertebrates.
Functions:
Cushioning: Protects from injury by distributing force.
Lubrication: Lubricates the brain, spinal cord, and surrounding bones.
Nutrients: Provides nutrients to the brain and spinal cord.
Waste removal: Removes waste from the brain.
Pressure regulation: Maintains constant pressure within the cranium.
Requires 20% more oxygen than other organs.
Skull Fractures: Severity determines need for surgery.
Decompression of the bone and plated back into place.
CSF Leak: Can present through the eyes and nose.
Diagnosis: History, CT scan, MRI, and biopsy.
Tumors: Can be benign or cancerous.
Surgery is performed to remove them if possible.
The brain doesn't regenerate, so the risk of damage is considered.
Radiation can be used to shrink tumors.
Brain Lesions: Areas of brain tissue that show damage from injury or disease.
Brain Tumors
Benign Tumors: Can be life-threatening if located in vital areas; rarely become malignant.
Meningioma: Most common primary brain tumor; slow-growing tumor from the meninges.
Pituitary Adenoma: Slow-growing tumor causing vision and endocrinological problems; occurs in the pituitary gland.
Craniopharyngioma: Benign tumor pressing on nerves, blood vessels, or parts of the brain; derived from pituitary gland embryonic tissue; common in children and adults.
Schwannoma: Benign, slow-growing tumor causing hearing loss; nerve sheath tumor composed of Schwann cells.
Hemangioblastoma: Benign tumor of the blood vessels; often removable through surgery.
Germ Cell Tumor: Neoplasm derived from primordial germ cells; can be cancerous or benign; originates outside the gonads due to errors during development.
Malignant Tumors: Cancerous, grow rapidly, and invade surrounding healthy brain structures.
Glioblastoma: Most aggressive and common type of cancer originating in the brain; poor prognosis.
Olfactory Neuroblastoma (Esthesioneuroblastoma): Rare, malignant tumor starting in the nasal cavity and growing into the brain; can spread to other parts of the body.
Chondrosarcoma: Rare, malignant, cancerous bone tumor that can develop in the skull base.
Medulloblastoma: Common type of primary brain cancer in children; originates in the cerebellum or posterior fossa.
Astrocytoma: Originates from astrocytes in the cerebrum; usually does not spread outside the brain and spinal cord.
Oligodendroglioma: Type of glioma believed to originate from oligodendrocytes or glial precursor cells.
Ependymoma: Arises from the ependyma of the central nervous system; intracranial in pediatric cases, spinal in adults; common location is the fourth ventricle.
Lymphomas: Can spread from other body parts to the brain or form in the brain (primary central nervous system lymphomas); starts in lymphocytes.
Other Pathological Conditions
Aneurysm: Cerebrovascular disorder where a blood vessel in the brain weakens and balloons out.
Rupture can cause subarachnoid hemorrhage (SAH), hemorrhagic stroke, brain damage, coma, or death.
Vascular Malformation: Rare and complex abnormality in blood vessels or lymph vessels that can develop before birth.
Can cause vessels to enlarge, form tangles, or create shunting vessels, leading to abnormal blood flow.
Hematomas: Collection of blood within the skull, usually caused by a burst blood vessel or trauma.
Blood may collect in brain tissue or underneath the skull, pressing on the brain.
Cerebral Ischemia: Medical emergency where blood flow to the brain is insufficient to meet metabolic demands.
Leads to poor oxygen supply (cerebral hypoxia), damaging or killing brain tissue.
Can result in cerebral infarctions or global hypoxic-ischemic encephalopathy, which can be fatal or cause permanent disability.
Surgical Procedures
Stereotactic Brain Biopsy:
A small sample of tissue is taken from the brain through a hole in the skull.
Used to take a sample from a tumor.
Creates a 3D representation of the brain using scans and computer technology for precise targeting.
Deep Brain Stimulation (DBS):
A neurostimulator and electrodes are implanted to send electrical impulses to specific targets in the brain responsible for movement control.
Can help manage Parkinson’s disease, epilepsy, and Tourette syndrome.
Craniectomy:
Removal of a bone block without replacing it to avoid pressure and damage to the brain due to postoperative swelling.
Chiari Malformation (Foramen Magnum Decompression):
An abnormality that results in a part of the brain extending into the upper spinal canal.
Small sections of bone are removed from the rear of the skull and spine to create more space for the errant brain tissue.
Craniotomy:
A piece of the skull is removed to help with brain swelling, relieve pressure, or remove a subdural hematoma due to trauma.
Reasons:
Removing blood or blood clots from a leaking blood vessel.
Removing an arteriovenous malformation (AVM) or addressing an arteriovenous fistula (AVF).
Draining a brain abscess.
Repairing skull fractures.
Craniotomy Hematomas
Result from trauma to the head; can also occur spontaneously in patients with abnormally high blood pressure or a blood vessel abnormality.
Intracerebral Hematoma: Blood clot inside the brain.
Epidural Hematoma: Between the skull and the dura.
Subdural Hematoma: On the surface of the brain.
Awake Craniotomy:
A special type of craniotomy performed when a tumor or lesion is located in very sensitive areas of the brain.
Recommended to preserve speech and language abilities.
Brain Aneurysm Treatment:
Coil Embolization: A small, soft metal coil is placed inside the aneurysm to block blood flow and prevent rupture.
Clipping: A small, metal clip is applied to the base of the aneurysm to prevent blood leakage.
Stenting
Resection of Cerebral Arteriovenous Malformation (AVM):
Performed under general anesthesia; the surgeon opens the skull to remove an abnormal tangle of enlarged blood vessels (AVM).
Generally used for small AVMs located on/near the surface of the brain.
Stereotactic Radiosurgery:
A nonsurgical procedure used to treat AVMs located deep inside the brain.
Beams of radiation are precisely focused at the AVM, destroying the abnormal vessels.
Cranioplasty:
A reconstructive surgical procedure to correct congenital problems or repair the skull after a traumatic injury or medical procedure.
A custom plate (porous plastic or titanium) is fitted over the defect in the skull.
Materials:
Autologous bone grafts
Metal plates
Synthetic materials
Titanium
Synthetic bone substitute
Solid biomaterial
Endoscopic Surgery:
Minimally invasive endonasal endoscopic surgery: tumors/lesions are removed through the nose and sinuses.
Transsphenoidal: Used to remove a tumor from the pituitary gland.
Stealth Guided: Advanced computer-assisted, image-guided navigational systems for neurosurgery.
Ventriculoperitoneal Shunt for Hydrocephalus:
A small drainage tube is implanted to relieve the pressure of hydrocephalus.
Hydrocephalus occurs when CSF doesn't drain properly from the brain's ventricles, caused by blockages, cysts, tumors, or inflammation.
Draining the extra fluid helps prevent pressure from building up in the brain.
Nerve Releases:
Treat nerve pain caused by entrapment.
The surgeon cuts/removes tissue compressing the nerve (ligaments or collagen bands) to relieve pressure and restore proper nerve function.
Can help with pain, numbness, tingling, or weakness.
Nerve hydrodissection (NRRIT): Injecting a natural solution around the entrapped nerve to nourish it and release it from surrounding tissue.
Common Locations:
Carpal tunnel: In the wrist
Cubital tunnel: In the elbow
Radial tunnel: In the forearm
Tarsal tunnel: In the ankle
Peroneal: In the knee
Spine Surgery
Spine Anatomy:
Vertebral Body
Disc
Nerve Root
Spinal Column
Spine Table:
Offers radiolucency through the whole working length of the table.
The Mayfield can attach to this bed.
Jackson frame for any spine cases.
Wilson mainly for Any type of laminotomy; fusion or hemi.
Cervical spine and anterior approach may do on a regular bed.
Lumbar Punctures:
Also known as spinal taps: a needle is inserted into the spinal canal to extract cerebrospinal fluid.
Diagnostic surgery that tests for conditions such as leukemia and meningitis.
Discectomy:
Correcting a herniated disc (frequently causes neck and/or arm pain).
Done through the neck, and then the bones are fused together.
If a spinal disc is damaged beyond repair, it can be removed and replaced with an artificial one.
Minimally Invasive Lumbar Discectomy: Small incisions and use microscope.
Anterior Cervical Discectomy and Fusion (ACDF)
Spine Fusion:
A surgical procedure to join two or more bones of the spine together, eliminating movement between them.
Used for fixing broken bones, reshaping the spine, or making the spine more stable.
Can also be used to stop the progression of scoliosis or other deformities, treat injuries, or stabilize a loose vertebrae.
Types:
Transforaminal Lumbar Interbody Fusion (TLIF)
Lateral Lumbar Interbody Fusion (LLIF)
Posterior Lumbar Interbody Fusion (PLIF)
Anterior Lumbar Interbody Fusion (ALIF)
Laminectomies:
Procedures that can relieve severe back pain; a major surgical procedure that involves removing part or all of the lamina.
Removing all or part of a vertebra (roof) of the spinal canal to relieve pressure on the spinal cord or nerves.
Conditions treated:
Herniated or prolapsed discs
Spinal stenosis
Bone spurs
Tumors
Arthritis
Injuries
Performed to widen the spinal column by removing the backside of the spinal canal along with any spurs that may have formed.
Anterior and Lateral Approach:
A method of operating on the spine from the front.
Large blood arteries run directly in front of the vertebral bodies of the spine.
A vascular surgeon or general surgeon is required to assist.
The choice of an open anterior approach to the spine is based on factors including the type of scoliosis, location of the curvature of spine, ease of approach to the area of the curve, and the preference of the surgeon.
Some scoliosis curves, such as those involving the thoracolumbar spine, are especially amenable to the anterior approach.
Vertebroplasty:
Performed as a result of a compression fracture of the vertebrae.
A cement-like material is injected into the vertebrae with a needle and bonds together the fractured pieces of bone.
AKA a Kyphoplasty.
Foraminotomy:
Can relieve pain associated with a compressed nerve in the spine.
The space where nerves exit the spine is widened by cutting away bones on the side of the vertebrae, releasing the pressure and easing pain.
Interlaminar Implant:
A type of spinal surgery involves implanting a U-shaped device between two vertebrae to maintain their space and ease the pressure on spinal nerves.
Comparison of Spinal Fusion Approaches (LLIF vs. Traditional)
Benefit | LLIF Approach | Traditional Approaches |
|---|---|---|
Hospital Stay | 1-2 days* | 3-5 days |
Blood Loss | <100cc* | 300-600cc |
Walking | Same day* | 2-4 days |
Return to Activities of Daily Living | 4-6 weeks | 6 months or longer |
LLIF = Lateral Lumbar Interbody Fusion, PLIF = Posterior Lumbar Interbody Fusion, ALIF = Anterior Lumbar Interbody Fusion, TLIF = Transforaminal Lumbar Interbody Fusion.