Anatomy Topic 3 Case 1 Flashcards
How many bones are there in the skull?
- 22
Which bones make up the calvaria?
- Frontal
- Sphenoid
- Temporal
- Parietal
- Occipital
Which bones make up the viscerocranium?
- Maxilla
- Zygomatic
- Lacrimal
- Ethmoid
- Palatine
- Vomer
Which bones make up the base of the skull?
- Sphenoid
- Temporal
- Occipital
Where is the coronal suture located?
- Between the frontal and parietal bones in the coronal plane
Where is the sagittal suture located?
- Between the two parietal bones in the sagittal plane
Where are the lambdoid sutures located?
- Between the parietal and occipital bones
Identify three sutures that connect the temporal bone with surrounding bones
- Squamous suture
- Sphenosquamous suture
- Occipitomastoid suture
Identify 5components of the anterior cranial fossa
- Frontal crest
- Cribiform plate
- Body of sphenoid
- Lesser wing of sphenoid
- Anterior clinoid processes
Identify 8components of the middle cranial fossa
- Tuberculum sellae
- Hypophyseal fossa
- Dorsum sellae
- Greater wings of sphenoid
- Tegmen tympani
- Foramen rotundum
- Foramen ovale
- Formane spinosum
Identify 6components of the posterior cranial fossa
- Clivus
- Internal acoustic meatus
- Jugular foramen
- Formane magnum
- Internal occipital crest
- Internal occipital protuberance
What structures pass through the cribiform plate?
- Olfactory nerve
What structures pass through the optic canal?
- Optic nerve
- Ophthalmic artery
What structures pass through the superior orbital fissure?
- Ophthalmic nerve
- Oculomotor nerve
- Trochlea nerve
- Abducens nerve
- Superior ophthalmic vein
What structures pass through the foramen rotundum?
- Maxillary nerve
What structures pass through the foramen ovale?
- Mandibular nerve
What structures pass through the foramen spinosum?
- Middle meningeal artery
What structures pass through the carotid canal?
- Internal carotid artery
What structures pass through internal acoustic meatus?
- Facial nerve
- Vestibulocochlear nerve
What structures pass through the jugular foramen?
- Glossopharyngeal nerve
- Vagus nerve
- Accessory nerve
- Internal jugular vein (which is a continuation of the sigmoid sinus)
What structures pass through the hypoglossal canal?
- Hypoglossal nerve
What structures pass through the foramen magnum?
- Spinal cord
- Vertebral arteries
- Accessory nerve
Which structures pass through the stylomastoid foramen?
- Facial nerve
What are fontanelles?
- Unossified gaps between bones of skull
Identify the four fontanelles and when they close?
- Lambda which closes to 3 months after birth.
- Sphenoidal fontanelle which closes around 6 months after birth.
- Mastoid fontanelle closes between 6 and 18 months after birth.
- The bregma fontanelle closes between 10 and 24 months.
Which muscle(s) of mastication lies lateral to the infratemporal fossa?
- Masseter
Which muscle(s) of mastication are located in the infratemporal fossa?
- Medial and lateral pterygoid muscles
Which muscle(s) of mastication fills the temporal fossa?
- Temporalis
What type of joint is a temporomandibular joint?
- Modified hinge joint
Where is the temporomandibular joint formed?
- Head of mandible
- Articular tubercle of temporal bone
What type of cartilage covers the temporomandibular joint?
- Fibrocartilage
Identify three ligaments associated with the temporomandibular joint
- Lateral ligament from articular tubercle to neck of mandible
- Sphenomandibular from spine of sphenoid bone to lingula
- Stylomandibular joint from styloid process to angle of mandible
Identify which bones make up the anterior, medial and posterior walls of the pterygopalatine fossa
- Anterior: maxilla
- Medial: palatine
- Posterior: sphenoid
Which nerves pass through the pterygopalatine foramen?
- Maxillary nerve through foramen rotundum
- Nerve of pterygoid canal (from greater petrosal nerve, a branch of the facial nerve)
Identify the two layers of the cranial dura mater
- Periosteal layer containing meningeal arteries
- Meningeal which is continuous with spinal dura mater
How are the two layers of the cranial dura mater separated?
- Dural partitions
- Dural venous sinuses
Where is the falx cerebri located?
- Crescent shaped downward projection
- From crista galli of ethmoid bone to tentorium cerebelli
Where is the tentorium cerebelli located?
- Horizontal projection
- Posteriorly to occipital bone
- Laterally to petrous part of temporal bone
What is the tentorial notch?
- Anterior border of tentorium cerebelli
- Allows passage of midbrain
Where is the falx cerebelli located?
- Small midline projection at internal occipital crest
Where is the diaphragm sellae located?
- Horizontal projection covering the hypophyseal fossa
What is the infundibulum?
- Connection between pituitary gland and base of brain
Outline the arterial supply of the cranial dura mater
- Anterior meningeal artery (branch of ophthalmic artery from internal carotid artery)
- Middle meningeal artery (branch of maxillary artery from external carotid artery)
- Accessory meningeal artery (branch of maxillary artery from external carotid artery)
- Posterior meningeal artery (branch of ascending pharyngeal artery from external carotid artery)
- Meningeal branches from vertebral, occipital and ascending pharyngeal arteries
Outline the innervation of the cranial dura mater
- Anterior fossa from V1
- Middle fossa from V2 (medially) and V3 (laterally)
- Posterior fossa from C1-C3
Which layer of the cranial meninges is avascular?
- Arachnoid
Which layer of the cranial meninges closely invests the surface of the brain?
- Pia
Where is the extradural space located and how does it present on CT?
- Between periosteum and dura mater
- Convex shape
Where is the subdural space and how does it present on CT?
- Between dura and arachnoid mater
- Crescent shape
Where is CSF produced?
- Choroid plexus of brain ventricles
Outline the course of CSF through the brain ventricles
- From lateral ventricles to third ventricles through interventricular foramina
- From third ventricle to fourth ventricle through cerebral aqueduct
How does CSF enter the subarachnoid space?
- Through lateral and medial apertures in fourth ventricle
How does CSF enter the superior sagittal sinus?
- Through arachnoid granulations in SAS
What is the telencephalon?
- Cerebral hemipsheres
What is the diencephalon?
- Thalamus and hypothalamus
What is the mesencephalon?
- Midbrain
What is the metencephalon?
- Pons
- Cerebellum
What is the myelencephalon?
- Myelencephalon
Outline the course and branches of the vertebral arteries
- Arise from subclavian arteries
- Ascend through transverse foramina and enter foramen magnum
- Give off anterior and posterior spinal arteries, meningeal branch and posterior inferior cerebellar arteries
Outline the branches of the basilar artery
- Anterior inferior cerebellar
- Pontine
- Superior cerebellar
- Posterior cerebral
Outline the course and branches of the internal carotid arteries
- Arise from common carotid artery
- Enter cranial cavity through carotid canals
- Give off ophthalmic, posterior communicating, middle cerebral and anterior cerebral arteries
Where is the superior sagittal sinus located?
- Superior border of falx cerebri
Where is the inferior sagittal sinus located?
- Inferior border of falx cerebri
Where is the straight sinus located?
- Junction of falx cerebri and tentorium cerebelli
Which sinus empties into the right transverse sinus?
- Superior sagittal
Which sinus empties into the left transverse sinus?
- Straight
Which sinus does the transverse sinus drain into?
- Sigmoid
Where are the cavernous sinuses located?
- Either side of sella turcica
Which structures pass through the cavernous sinus?
- Internal carotid artery and abducens nerve
- In lateral wall pass the oculomotor, trochlea, ophthalmic and maxillary nerves
Where is the inter-cavernous located?
- Anterior and posterior sides of pituitary stalks
Which sinuses do the cavernous sinuses drain into? Which sinuses do these sinuses drain into?
- Superior and inferior petrosal sinuses
- Transverse sinuses
At which vertebral level does the spinal cord terminate?
- L1 - L2
At which vertebral level does the dura, arachnoid and pia mater terminate?
- S2
What is the filum terminale and at which vertebral level does it terminate?
- Coccyx
What is the purpose of a lumbar puncture?
- Obtain a sample of CSF for examination
At which vertebral level is the needle inserted? Why? Which surface anatomy landmark can help identify this position?
- Between L3 and L4
- Contains CSF but not spinal cord
- Supracristal plane, highest point of iliac crest
Why are nerves not damaged during a lumbar puncture?
- Needle pushes roots away
Why is local anaesthesia carried out in the erect position?
- So that anaesthesia is not unilateral
- And so that it does not descend cranially and cause respiratory depression
Identify the 9 features of the mandible
- Condylar process
- Coronoid process
- Mandibular notch
- Ramus
- Angle
- Body
- Mental foramen
- Lingula
- Mylohyoid groove and line
Identify the attachments of the denticulate ligaments
- Medially to spinal cord
- Laterally to dura between the rootlets
What is the function of the denticulate ligaments?
- Position the spinal cord in the centre of the subarachnoid space
What are subarachnoid cisterns and where are they found? What do they contain?
- Expanded areas of the subarachnoid space
- Contain CSF
- Above and bellow the cerebellum, in front of midbrain
