Session 1.4a - Self-Study Flashcards
Clinical Presentations - Retropharyngeal Abscesses https://www.youtube.com/watch?v=VnFDdC9sfYM
Why is an understanding of the cervical fascial layers and deep neck spaces important clinically?
(Clinical Presentation: Retropharyngeal abscesses)
When thinking about relation to deep neck space infections and their potential route of spread.
What might a presenting complaint and population be for those presenting with retropharyngeal abscesses?
(Clinical Presentation: Retropharyngeal abscesses)
Population - children under 5
Presenting complaint - unable to move her neck/neck stiffness
https://www.youtube.com/watch?v=VnFDdC9sfYM
Try and tie in her clinical symptoms with what you understand of the anatomy of the cervical fascial layers: for example, why might swallowing and moving the head prove painful for the young girl?
(Clinical Presentation: Retropharyngeal abscesses)
The retropharyngeal space is located directly behind the oesophagus. An infection here would cause this space to distend, hence impinging on the oesophagus, and making swallowing hard (substances pass from the mouth, pharynx to the oesophagus; while shutting the epiglottis).
Normally, the fascia also allows for ease of movement between structures, e.g. when swallowing - due to infection the fascia would be inflamed causing friction as the planes rub over each other, making movement difficult and painful.
Similarly, movement of the neck is difficult because posteriorly, the retropharyngeal space when distended would impinge on the muscles associated with the vertebral column; making it hard to move the neck.
https://www.youtube.com/watch?v=VnFDdC9sfYM
What would be another very important differential diagnosis to consider when a patient presents unwell, with apparent neck stiffness?
(Clinical Presentation: Retropharyngeal abscesses)
Meningitis
One of the differential diagnoses can be the Brudzinski sign
https://en.wikipedia.org/wiki/Brudzi%C5%84ski%27s_sign
IMAGE 1 - 00:08
What are we looking at?
(Internal Carotid Artery Route)
A model showing the skull, brain, and some of the important arteries that run up through the neck to supply various structures of the face and structures intracranially.
IMAGE 2 - 00:30
What can we see in this view?
(Internal Carotid Artery Route)
- Looking at the lateral aspect of the neck
- We see the main artery and its branches
- This essentially supplies the entirety of the structures of the face, the skull and intracranial contents
IMAGE 2 - 00:30
- Label the CCA, ICA and ECA.
- Label the vertebra
- Draw on the thyroid cartilage
(Internal Carotid Artery Route)
- The CCA bifurcates into the ICA and ECA
- The ECA gives off branches in the neck, whereas the ICA gives off no branches
- The CCA bifurcates at the level of C4
- The superior edge of the thyroid cartilage is C4 (thyroid cartilage roughly C4-C5)
How can you identify the difference between the ECA and ICA? What does the ECA supply?
(Internal Carotid Artery Route)
The ECA gives branches within the neck to supply various structures of the face, bones of the face, scalp and tissues of the scalp.
The ICA runs right up the length of the neck without giving any branches, and instead will pass through a tiny hole in the base of the skull, known as the carotid canal.
IMAGE 3 - 01:30
Where does the ICA enter the skull (answer without image and then show)
(Internal Carotid Artery Route)
Through the carotid canal
- 01:30
IMAGE 4 - 01:36
Label the image
(Internal Carotid Artery Route)
- Foramen ovale
- Pterygoid plates & fossa
- Carotid canal
- Jugular foramen
In relation to the ICA, what do we normally find at the site of bifurcation?
(Internal Carotid Artery Route)
A slight swelling, known as the carotid sinus
What does the carotid sinus do?
Important baroreceptors that monitor pressure within the vasculature (blood pressure)
Why is the carotid sinus important clinically?
Applying firm pressure over the area of carotid sinus (carotid sinus massage) can stimulate baroreceptors - this increases parasympathetic drive to the heart to terminate, hopefully, any potential supraventricular tachycardias (SVTs).
IMAGE 5 - 02:15
Label the image
(Internal Carotid Artery Route)
- Carotid sinus
- Vagus nerve
IMAGE 6 - 03:00
This view involves removing the brain. Here we can visualise a number of blood vessels.
Label the front and back of the skull.
What will these blood vessels ultimately give rise to?
Front, back - see image.
Arteries supplying the brain
How can you potentially terminate a SVT?
By applying a carotid sinus massage.
IMAGE 6 - 03:00
Label the ICA
ICA enters through the carotid canal
IMAGE 6 - 03:00
Label the carotid canal
See image
IMAGE 6 - 03:00
Label the sphenoid bone/body of sphenoid
See image (central bone)
What is the dural venous sinus which sits either side of the sella turcica known as?
Cavernous sinus
IMAGE 6 - 03:00
Label the sella turcica
See image (central depression)
IMAGE 6 - 03:00
Label the petrous bone
Bone on middle lateral edges
Describe the route of the ICA in the skull.
The ICA arises from the carotid canal in the petrous bone, coming through and running towards the body of the sphenoid bone. Here it runs into the cavernous sinus, which is a dural venous sinus which sits either side of the sella turcica. As it emerges through the top of the cavernous sinus, this is when it gives its branches.
IMAGE 7
Label the image and caption it with specific description of image.
- ORBIT and EYE
- OPTIC CANAL with ophthalmic artery from ICA
- ophthalmic vein
- posterior clinoid process (sella turcica)
- superior petrosal sinus
- inferior petrosal sinus
- petrous part of temporal bone
- carotid canal
- cavernous sinus
- emissary vein connecting to pterygoid venous plexus
- ICA
Looking laterally towards right hand side of sella turcica on cranial floor
The ophthalmic artery is a branch of which artery?
The ICA
IMAGE 8
Label the ophthalmic artery
Runs through the optic canal
Where does the ophthalmic artery lie in the skull?
Essentially arises just after the CCA (ICA?) has emerged to the top of the cavernous sinus