Anatomy Final Flashcards
What runs through the optic nerve?
- Central Artery of Retina 2. Central Vein of Retina
Fibers of oculomotor nerve
- motor 2. proprioceptive 3. PSNS (pregang to ciliary ganglion)
Sxs of oculomotor paralysis
- Ptosis of upper eyelid (levator palpebrae superioris) 2. Abduction of eye (unopposed LR and SO) 3. Dilation of Pupil (Sphincter pupillae muscle lost)
What is unique about the trochlear nerve?
It is the only cranial or spinal motor nerve arising from the dorsal aspect of the CNS
“Weakling of the Cranial Contents”
Abducens -Susceptible to injury because stretched across the petrous part of the temporal bone
Parent of the ophthalmic artery
Cerebral part of the internal carotid artery
Branches of ophthalmic artery
- Central artery of retina 2. Several arteries to the eye 3. Lacrimal artery 4. Conjunctival Arteries 5. Ethmoidal Arteries (anterior and posterior) 6. Branch that anastomoses with angular branch of facial artery
Ophthalmic veins
- Superior ophthalmic vein 2. Inferior ophthalmic vein
What forms the superior ophthalmic vein?
- Supraorbital Vein 2. Angular Vein
Where do the opthalmic veins end?
the cavernous sinus
Where does the inferior ophthalmic vein begin?
Plexus on floor of orbit
Where does the central vein of the retina run?
To the cavernous sinus directly
What forms the straight sinus?
- Inferior sagittal sinus 2. Great cerebral vein (of Galen)
Where are GSEs and GSAs found?
The entire body
What do GVEs and GVAs innervate?
Smooth muscle, cardiac muscle, and glands
SVE
Innervates all pharyngeal-derived muscles
SVA
Special sense of taste and smell
SSA
Special sense of hearing and sight
CNs with PSNS fibers
- # 3 Oculomotor 2. #7 Facial 3. #9 Glossopharyngeal 4. #10 Vagus (V3 also has PSNS fibers but they do not come from the brain)
Inferior Alveolar Nerve Fiber Types (before and after giving off mylohyoid nerve)
Before: GSA, SVE -After: GSA (Mylohyoid takes SVE)
Lingual Nerve fiber types (before and after receiving chorda tympani)
Before: GSA -After: GVE, GSA, SVA
Pain pathway for spinal nerves
Dorsal root ganglion –> Chief nucleus of dorsal horn –> crossover –> ascend in Lateral spinothalamic tract –> ventral posterior thalamic nucleus –> somesthetic area/post-central gyrus
Cell body locations (spinal nerve pain)
- Dorsal root ganglion 2. Chief nucleus of dorsal horn 3. ventral posterior thalamic nucleus
Pain pathway for trigeminal nerve
Trigeminal ganglion –> pons –> descends in spinal tract of trigeminal nerve –> nucleus of spinal tract of trigeminal nerve in medulla –> crossover –> ascends in trigeminothalamic tract –> ventral posterior thalamic nucleus –> Somasthetic area/post-central gyrus
Cell body locations (trigeminal nerve pain)
- Trigeminal ganglion 2. Nucleus of spinal tract of trigeminal nerve 3. Ventral posterior thalamic nucleus
Parts of Nucleus of Spinal tract of trigeminal nerve and respective functions
- Nucleus rostralis (simple touch and pressure) 2. Nucleus interpolaris (simple touch and pressure) 3. Nucleus caudalis (pain)
Where does the nucleus of the spinal tract of the trigeminal nerve extend?
from the medulla to the upper cervical spinal cord
What carries all the pain fibers from all the spinal nerves?
Lateral spinothalamic tract
Simple touch and pressure pathway for spinal nerve
Dorsal root ganglion –> ascends 4-5 levels –> cheif nucleus of dorsal horn –> crossover –> ascends in ventral spinothalamic tract –> ventral posterior thalamic nucleus –> somesthetic area/post-central gyrus
Cell body locations (spinal nerve simple touch and pressure)
- Dorsal root ganglion 2. chief nucleus of dorsal horn (4-5 levels higher than entry level) 3. ventral posterior thalamic nucleus
Simple touch and pressure pathway for trigeminal nerve (2 options)
From Trigeminal Ganglion: 1. descend to medulla in spinal tract of trigeminal nerve –> nucleus of spinal tract of trigeminal nerve –> crossover –> ascend in trigeminothalamic tract –> ventral posterior thalamic nucleus –> post-central gyrus 2. chief sensory nucleus of trigeminal nerve in pons –> crossover –> ascend in tigeminothalmic tract –> ventral posterior thalamic nucleus –> post-central gyrus
Location of cell bodies (simple touch and pressure trigeminal nerve)
- Trigeminal ganglion 2. Chief sensory nucleus of trigeminal nerve or nucleus of spinal tract of trigeminal nerve 3. ventral posterior thalamic nucleus
Divisions of spinal nerves in proproception pathway
- C1-T7or8 2. T8-CX1
Proprioceptive pathway for upper division of spinal nerves
Dorsal root ganglion –> Fasciculus cuneatus –> Nucleus cuneatus in medulla –> crossover –> Medial lemniscus –> ventral posterior thalamic nucleus –> post-central gyrus
Proprioceptive pathway for lower division of spinal nerves
Dorsal root ganglion –> Fasciculus gracilis –> nucleus gracilis in medulla –> cross over –> Medial lemniscus –> ventral posterior thalamic nucleus –> post-central gyrus
Location of Cell bodies (proprioceptive of spinal nerves)
- Dorsal root ganglion 2. Nucleus cuneatus (upper) or Nucleus gracilis (lower) 3. Ventral posterior thalamic nucleus
Proprioceptive pathway for trigeminal nerve (normal pathway)
Trigeminal ganglion –> Chief sensory nucleus of trigeminal nerve in pons –> cross over –> trigeminothalamic tract –> ventral posterior thalamic nucleus –> post-central gyrus
Proprioceptive pathway for trigeminal nerve (TMJ)
Goes through trigeminal ganglion without synapsing –> Mesencephalic nucleus of trigeminal nerve in midbrain –> crosses over –> trigeminothalamic tract –> ventral posterior thalamic nucleus –> post-central gyrus
Location of cell bodies (proprioceptive for Trigeminal nerve)
- Trigeminal nerve or mesencephalic nucleus of trigeminal nerve 2. Chief sensory nucleus of trigeminal nerve or mesencephalic nucleus of trigeminal nerve 3. Ventral posterior thalamic nucleus
Locations of main nuclei of trigeminal nerve pathways (superior to inferior)
- Mesencephalic nucleus of trigeminal nerve (midbrain) 2. Chief sensory nucleus of trigeminal nerve (pons) 3. Nucleus of spinal tract of trigeminal nerve (medulla)
Divisions of the Pyramidal system
- Corticospinal (all spinal nerves) 2. Corticobulbar (all cranial nerves)
Corticobulbar pathway
Pre-central gyrus –> internal capsule –> crossover –> synapse with respective nuclei –> send off lower motor neuron
Corticospinal pathway
Pre-central gyrus –> internal capsule –> Pyramid of medulla –> Fibers to ventral (15%) corticospinal tract then crossover at respective level or crossover and then to lateral spinothalamic tract (85%)
Nuclei for corticobulbar fibers (location and nerves)
- Facial motor nucleus (pons): Facial Nerve 2. motor nucleus of trigeminal nerve (pons): Trigeminal nerve 3. Hypoglossal nucleus (medulla): Hypoglossal nerve 4. Nucleus ambiguus (medulla): CNs 9, 10, and 11
Cell body locations (corticobulbar)
- Pre-central gyrus 2. Respective motor nuclei
Cell body locations (corticospinal)
- Pre-central gyrus 2. respective ventral horns
Olfactory Nerve CNFT
Sense of smell
Optic nerve CNFT
sense of sight
Oculomotor CNFT
- motor innervation to SR, IR, MR, IO and levator palpebrae superioris 2. PSNS to ciliary muscles (pregang. to ciliary ganglion)
Trochlear CNFT
innervates Superior oblique
Ophthalmic CNFT
- Corneal reflex (afferent: nasociliary; efferent: facial) 2. Sensation in forehead, upper eyelid, superior part of external nose, and tip of nose (frontal and nasociliary nerves)
Maxillary Nerve CNFT
- Cutaneous distribution (upper lip, lateral nose, lower eyelid, zygoma) 2. Teeth and gingiva (sup. alveolar, nasopalatine, and greater palatine nerves) 3. Some nasal cavity
Mandibular nerve CNFT
- Cutaneous distribution over body of mandible and ramus (lower lip, cheek, area over parotid, lateral aspect of scalp) 2. Oral cavity: general sensation to teeth, gums, floor of mouth, ant. 2/3 tongue, and cheek 3. Motor root
Motor root tests for Mandibular nerve
- Clench jaw (masseter and temporalis tone) 2. Open mouth (inferior head of lateral pterygoid paralysis moves to affected side) 3. Lateral excursion against resistance (inferior head of lateral pterygoid) 4. Protract and retract mandible 5. Bite tongue depressor and compare strength 6. Sensitivity to loud noises (tensor tympani) 7. Soft palate dysfunction (tensor veli palatini) 8. Flaccid floor of mouth (ant. belly digastric and mylohyoid)
Abducens CNFT
Motor innervation to LR
Vestibulocochlear CNFT
Equilibrium and and hearing
Glossopharyngeal CNFT
- Gag reflex by touching anterior pillars or base of tongue 2. Parotid gland secretion with Vit. C/Spicy food
Vagus CNFT
- Say “ah,” uvula should rise, otherwise deviation towards opposite side of dysfunction 2. Swallowing and no hoarseness
Spinal Accessory CNFT
Traps and SCM
Hypoglossal CNFT
- Lateral deviation to nonfunctional side during protrusion of tongue (genioglossus) 2. Lateral movements of tongue (move tongue depressor or cheek) 3. Paralysis leads to wrinkling and atrophy of tongue on affected side
What does the internal carotid artery supply?
- Frontal lobe 2. Parietal lobe 3. Part of temporal lobe (anterior and superior part of cerebrum)
Parts of Internal carotid artery
- Cervical: in neck 2. Petrous: through carotid canal 3. Cavernous: enters cavernous sinus along carotid sulcus 4. Cerebral: gives off middle and anterior cerebral arteries
Branches of Internal Carotid artery
- branches to trigeminal ganglion, dura, and hypophysis 2. Ophthalmic artery 3. Posterior communicating artery (to posterior cerebral artery) 4. Anterior cerebral artery 5. Middle cerebral artery
Branch of anterior cerebral artery
Anterior communicating artery
Where does the anterior cerebral artery travel?
In the longitudinal fissure
Where does the middle cerebral artery travel?
in the lateral fissure
What does the middle cerebral artery supply?
A lot of the brain including the motor and sensory cortices
Deficits from occlusion of Anterior cerebral artery
Area of knee and below
Deficits from occlusion of middle cerebral artery
Contralateral paralysis (hemiplagia) excpet for knee and below
Branches of vertebral arteries
- Spinal cord branches 2. Posterior inferior cerebellar arteries 3. Forms basilar artery
Branches of basilar artery
- Anterior inferior cerebellar artery 2. Superior cerebellar arteries 3. splits into posterior cerebral arteries
What do the vertebral and basilar arteries supply?
- Upper spinal cord 2. Brainstem 3. Cerebellum 4. Part of temporal lobe 5. Occipital lobe (Posterior and inferior part of cerebrum)
What vessels form the circle of Willis?
- Posterior cerebral arteries 2. Posterior communicating artery 3. Internal carotid artery 4. Anterior cerebral artery 5. Anterior communicating artery
Layers of the Dura Mater
- Endosteal layer: on insde of cranial bones 2. Meningeal Layer
Another name for meningeal layer of dura
Projecting layer of dura
Processes of Meningeal layer of dura
- Falx Cerebri 2. Tentorium Cerebelli 3. Falx cerebelli 4. Diaphragma Sellae
Where is the endosteal layer of dura continuous with pericranium (external periosteum)?
Sutures and foramina
Where is the falx cerebri located?
in the longitudinal fissure
What is the anterior and posterior attachment point for the falx cerebri?
Anterior: Crista galli -Posterior: Fuses with tentorium cerebelli
What encloses the superior sagittal sinus
Falx Cerebri
What is contained in the inferior border of the flax cerebri
inferior sagittal sinus
Where is the tentorium cerebelli located?
between the occipital lobe and cerebellum
Interior border of tentorium cerebelli
Tentorial notch, which allows communicating between brain and spinal cord
External border of tentorium cerebelli
encloses transverse sinuses, superior petrosal sinus, and cavernous sinus
What forms the Cavum Trigeminali?
Tentorium cerebelli
Contents of Cavum trigeminali
Trigeminal ganglion and nerve
Buccal space
Space between masseter and buccinator
What encloses the straight sinus?
- Tentorium cerebelli 2. Falx cerebri
Pterygopalatine space (main N, main A)
Main N: Maxillary Nerve S2 -Main A: Maxillay Artery
What encloses the occipital sinus?
Falx cerebelli
Retromandibular space (aka)
Parotid space -investing fascia around Parotid gland and contents (parotideomasseteric fascia)
Where is the falx cerebelli located?
between hemispheres of cerebellum