Neurology Anatomy Flashcards
What are the constrictions of the esophagus?
- Cricopharyngeus M
- At the aortic arch
- Left bronchus
- Esophageal hiatus of the thoracic diaphragm (lower esophageal sphincter)
Right vagus nerve splits into what
Posterior vagal trunk–> goes BEHIND the esophagus
Left vagus nerve splits into?
Anterior vagal trunk, which goes in FRONT of the esophagus
Where do the anterior and posterior vagal trunks enter?
abdomen through hte esophageal hiatus
What nerve roots does the PHRENIC NERVE come off of?
anterior rami of C3, 4, 5
KEEP THE DIAPHRAGM ALIVE
Vagus N branches
L/R Recurrent Laryngeal N
Posterior and Anterior Vagal trunks
Superior cardiac branch, Middle cardiac branch and the inferior cardiac branch,
Pulmonary branch
Esophageal branch
Where is the phrenic N found?
Between the [fibrous pericardium] and [mediastinal parietal pleura]
All of the intercostal nerves are ANTERIOR/POSTERIOR rami of spinal nerves in the thoracic segment?
ANTERIOR RAMI
How many intercostal nerves are there?
11 pairs
What are the atypical intercostal nerves?1
1-2
7-11
What are the three major branches of the intercostal N?
- Lateral cutaneous branches
- muscular branches
- Anterior cutaneous branches
- Rami communicantes ( to sympathetic trunk)
Atypical intercostal nerves
1st one- majority of the anterior ramus of the 1st thoracic spinal nerve joins the brachial plexus
2nd- makes a cutaneous branch that joins a brachial component–> the intercostobrachial nerve (supplies skin and subcutaneous tissue of the armpit-axilla
7-11- as they run around the ribs, they continue past and become thoracoabdominal nerves
Nerve root of intercostal nerves
anterior ramus of T1-T11
What would be the 12th intercostal nerve doesn’t have a rib above and below it, so it is just called the ______ nerve.
subcostal
What are the typical intercostal N?and what are the branches?
Spinal nerves 3-6.
Have
- Rami communicantes
- Collateral branches
- Lateral cutaneous branches - supply skin of the thoracic wall and T4-T6 go to the breast
- Anterior cutaneous branches- anterior aspect of the thoracic wall and T4-T6 supply breast
- Muscular branches innervates the muscles
The intercostal nerves communicate with the __________ using rami communicantes
thoracic sympathetic trunk
Sympathetic NS is considered _________
catabolic- fight or flight
Parasympathetic NS is considered __________
ANABOLIC
What is the distribution of the parasympathetic innervation?
Has limited distribution (head, neck, trunk viscera)
NEVER in the body wall or extremeties
What is the distribution of the sympathetic innervation?
EVERYTWHERE.
distributes to all vacular areas of the body; like SWEAT gland and smooth muscle
Most glands (NOT SWEAT) are ______
PARASYMPATHETIC
Can the Sympathetic NS affter non-sweat glands glandular secretion?
INDIRECTLY, yes.
Through vasoconstriction.
Vasoconstriction is ___________ stimulated?
SYMPATHETICALLY (except coronary as)
Where are the cell bodies for the sympathetic NS found, and what are they called?
T1-L2
—-and thus, called—-
THORACOLUMBAR
Sympathetic NS
- Pre-synpatic
- Post-synaptic.
Which are long and which are short
-Pre-synpatic- SHORT
-Post-synaptic- LONG
Path of sympathetic pre-synaptic nerves
- CB is located in the lateral horn of the spinal cord, found in T1-L2
- Anterior root–>
- Into the anterior ramus–>
- Quickly exit and enter the PARAVERTEBRAL GANGLIA
Why is there only 1 rammus communicantes in regions other than T1-L2?
Bc they dont have presynaptic CB that need to communicate with paravertebral ganglia
What are the synaptic options for pre-sympathetic ganglia of sympathetic nerves?
- Presynaptic fibers –> paravertebral ganglia–> synpse with a post-synaptic nerve on the SAME LEVEL–> innvervate an organ via the splanchnic nerve
- Presynaptic fibers –> paravertebral ganglia–> ascend or descent to synapse on a post-synaptic neuron ON A DIFF LEVEL. This si why the paravertebral ganglia are all connected
- Presynaptic fibers–> pass through the paravertebral ganglia–> exit w/o synapsing–> leave via a ABDOMINOPELVIC SPLANCHNIC N–> 1/4 prevertebral ganglia in abdomen
What is a result of option 3
We can have pre and post synaptic splanchnic nerves
Why are all of the paravertebral ganglia linked together?
BEcause the presynaptic neurons of the symapthetic NS can go their the paravertebral ganglia at their level and ascend or descend into a different one
Where are the post-synaptic fibers of the sympathetic NS located?
In the prevertebral ganglion or the paravertebral ganglion.
What are the prevertebral gangia called?
- Celiac ganglion
- Superior mesenteric gangion
- Aorticorenal ganglion
- Inferior mesenteric ganglion
What is the thoracic sympathetic trunk
Location of paravertebral ganglia, where presynaptic sympathetic fibers synapse on the the CB of post-synpatic sympathetic fibers
Cardiac splanchnic N
Presynaptic CB in the lateral horn of the spinal cord at T1-5/6.
Synapse on postynaptic CB in the [cervical and thoracic sympathetic trunks]
Pulmonary splanchnic nerves
Presynaptic CB located in the lateral horn of the spinal cord at T2-T3 and synapse on post-synpatic CB in the thoracicic smpathetic trunk
Abdominopelvic splanchnic nerves
Go from the thoracic sympathetic trunk–> prevertebral ganglia in the abdomen.
These nerves headed to the abdomen are called
GREATER, LESSER AND LEAST
Greater splanchnic nerves–> arise when all nerves combine
Spinal roots of Greater splanchinic nerve
what prevertebral ganglion do they go to?
T5-T9/10
–> celiac ganglion
Lesser splanchnic N spinal roots
what prevertebral ganglion do they go to?
T10/11
–> celiac and superior mesenteric ganglion
Least splanchnic N spinal roots
what prevertebral ganglion do they go to?
T12
–> aorticorenal ganglion
What cranial nerves contribue to the parasymapthetic NS?
3, 7, 9, 10
S2-S4 (sacral part of the spinal cord)
Where are the nerves of the parasympathetic NS called?
CRANIOSACRAL
What is the presynaptic sacral part of the Parasympathetic NS called?
Anterior rami of the sacral spinal nerves, which are called pelvic splanchnic nerves.
Parasympathetic NS
Presynaptic fibers are ______
Post-synaptic fibers are _____
Presynaptic- long
Post-synaptic- short ( with ganglia on the target organ)
Where are the nuclei/ganglia of post-synpatic parasympathetic fibers?
- Ciliary ganglion
- Pterygopalatine ganglion
- Otic ganglion
- Submandibular ganglion
Parasympathetic NS in the thorax is all _____ nerve
VAGUS
What is the vagus nerve?
Presynaptic PARASYMPATHETIC innervation to the lungs, bronchi, pleura, heart and pericardium
Branches of the vagus n
3 branches to the heart (superior cardiac branch, middle cardiac branch, inferior cardiac branch)
- Pulmonary branch
- esophageal branch
SYMPATHETIC
- Location of presynapthic CB
- Presynaptic Cfibers
- Post-synaptic CB
- What do the post-synaptic fibers form?
- Lateral horn of the spinal cord
- Presynaptic cell fibers: anterior root–> anterior ramus–> paravertebral ganglion at the same level or abdominopelvic splanchnic nerves
- Paravertebral ganglio nat the same level, different level or prevertebral ganglion
- Form the thoracic autonomic plexus
PARASYMPATHETIC
- Location of presynapthic CB
- Presynaptic Cfibers
- Post-synaptic CB
- What do the post-synaptic fibers form?
- Cranial part- brain stem; sacral part: sacral part of the spinal cord
- Cranial part: 4 cranial nerves act as the presynaptic cell fibers
Sacral part- presyanptic cell fibers are the pelvic splanchnic nerves
- Post synaptic cell bodies: 4 cranial ganglia in the target organ
- Post-synpatic fibers form the thoracic autonomic plexus
For each plexus, know if it is mixed sympathetic / parasympathetic or not, where each contribution comes from, but not what it does (for this lecture).
Pulmonary Plexus
Mixed/ sympathetic / parasympathetic
Where does each contribution come from?
- Sympathetic contribution- Pulmonary splanchnic nerves
- Parasympathetic contribution- pulmonary branches of the vagus nerve
Cardiac Plexus
Mixed/ sympathetic / parasympathetic
Where does each contribution come from?
Mixed: sympathetic and parasympathetic
- Sympathetic input- cardiac splanchnic N
- Parasympathetic input- Superior, middle and inferior cardiac branches of the vagus n.
Post synaptic fibers terminate near the SA and AV nodes.
Aortic Plexus
Mixed/ sympathetic / parasympathetic
Where does each contribution come from?
Mixed
Sympathethetic: continous with the superficial cardiac plexus
Parasympathetic contribution: continuouys with the superficial cardiac plexus
—This is more like a conduit
Esophageal Plexus
Mixed/ sympathetic / parasympathetic
Where does each contribution come from?
Sympathetic Contribution: Greater splanchnic N
Parasympathetic contribution: Esophageal branches of the vagus N
