Scalp, Dipole & Meninges Flashcards
Name the posterior margins of the scalp
Supraorbital margins back to the superior nuchal line
Name the lateral margins of the scalp
Extends down into the temporal fossa
What is the dipole?
The spongy bone between the outer and inner tables of skull bones
What is the origin of the Occipitofrontalis muscle?
Four bellies, two occipital bellies arise from the highest nuchal line , and two frontal bellies are attached to the skin of the eyebrows
Where do the 4 bellies of the Occipitofrontalis muscle meet?
The epicranial aponeurosis
What is the nerve supply of the Occipitofrontalis muscle?
Facial Nerve
What is the action of the Occipitofrontalis muscle?
Moves the scalp ,wrinkle the forehead and elevate the eyebrows
Name the layers of the scalp
Skin, Connective tissue (subcutaneous), Aponeurosis, Loose areole tissue, Pericranium (periosteum)
What does the skin of the scalp contain?
Hair follicles, sweat and sebacous glands
What does the connective tissue of the scalp contain?
Nerves and blood vessels This layer is also anchored to the layer above and below. Layer anchored to the skin & aponeurosis
What happens if the blood vessels in the CT of the scalp are injured?
Bleeds profusely if injured as the arterial walls here cannot retract
What is the role of the loose areolar tissue?
Allows movement of the above three layers as one unit on skull
What is the pericranium anchored to?
Bone
Where does scalp detachment occur?
The loose areolar tissue, the 4th plane. Infections and bleeding in this layer spread readily.
What is the aponeurosis?
An intermediate tendon for the bellies of occipitofrontalis - wounds will gap because of the pull of the bellies in opposite direction= sutures mandatory
The 1st 3 layers are connected and move as one unit and remain together when scalp is torn off during accidents.
Why will wounds gap in the aponeurosis?
Because of the pull of the bellies in opposite direction, however sutures are mandatory
What 3 layers of the scalp are connected?
The first 3: Skin, CT & Aponeurosis. They remain together when the scalp is torn off during accidents.
What is the danger area of the scalp and why?
The loose CT layer (layer 4)
Pus and blood spread easily in it
Why can pus or blood enter the eyelids?
Occipitofrontalis inserts into the skin and does not attach to the bone
How to black eyes occur?
Slight injury/inflammation result in accumulation of fluid causing the eyelids to swell. Therefore, black eyes can result from injury to scalp or forehead. the trauma its caused to eye but to head/forehead and the blood travels down due to gravity
What are the 3 meningeal layers that surround the brain? (From outermost to innermost )
Dura Mater
Arachnoid Mater
Pia Mater
Where is the arachnoid mater located?
Deep in the dura mater
Where is the Pia mater located?
Deep to the arachnoid mater
Where is the dura mater located?
Outer layer of the meningeal layer
What are the two divisions of the dura mater?
Outer periosteal
Inner meningeal
Describe the Pia mater
Follows contour of the cerebrum & is highly vascular mater
Describe the Arachnoid Mater
Subarachnoid space lies below it
What causes inflammation of the meninges?
Caused by bacterial, viral or fungal infections
What causes meningoencephalitis?
When meningitis is not treated correctly, Infective toxins may not only inflame the meninges but the underlying brain as well resulting in meningoencephalitis (result if meningitis is not initially treated correctly).
What is a symptom of meningoencephalitis?
Stiffness in the neck
What is the middle meningeal artery a branch of?
Maxillary artery
What is the maxillary artery a terminal branch of?
External carotid artery
What does the middle meningeal artery supply?
Dura mater, inner table of bone and diploe of cranial vault
What does the Middle Meningeal artery divide into?
An anterior and posterior branch
What does the middle meningeal artery ascend on?
The internal aspect of the skull
What is the pterion?
Region of meeting of frontal, parietal, squamous part of temporal and greater wing of sphenoid bones
What causes a extradural hemorrhage in the skull
Rupture of the middle meningeal artery or one of its branches
What nerve plays the role of motor action?
Facial Nerve
What nerve plays the role of sensory action?
Trigeminal Nerve
What are the 3 branches of the trigeminal nerve?
Ophthalmic Nerve, Maxiallry Nerve, Mandibular Nerve
What nerve supplies the chin?
Mental nerve
What is the innervation on the right side of the scalp, anterior to the ear (trigeminal nerve)?
Supratrochlear nerve
Supraorbital nerve
Zygomaticotemporal nerve
Auriculotemporal nerve
What is the innervation of the right side of the scalp, posterior to the ear (spinal nerve)?
Lesser occipital nerve
Greater occipital nerve
Third occipital nerve
What is the innervation of the left side of the scalp, posterior to the ear (cervical spinal nerve)?
Lesser occipital nerve
Greater occipital nerve
Third occipital nerve
What is the innervation of the left side of the scalp, anterior to the ear (trigeminal nerve)?
Supratrochlear nerve
Supraorbital nerve
Zygomaticotemporal nerve
Auriculotemporal nerve
What is the arterial supply to the scalp, anterior to ear (Ophthalmic artery)?
Supratrochlear artery
Supraorbital artery
What is the Ophthalmic artery a branch of?
Internal carotid artery
What is the arterial supply to the scalp, posterior to ear (External carotid artery)?
Post auricular artery
Occipital artery
What is the main nerve that supply’s the left side of the scalp, anterior to the ear?
Trigeminal Nerve
What is the main nerve that supply’s the left side of the scalp, posterior to the ear?
Cervical Spinal Nerve
What is the main nerve that supply’s the right side of the scalp, anterior to the ear?
Trigeminal Nerve
What is the main nerve that supply’s the right side of the scalp, posterior to the ear?
Spinal Nerve
