T1 L1 - The Skull and Cranial Cavity 23_24.html

The Skull and Cranial Cavity Module 202 - Theme 1 - Lecture 1 A riddle while you wait: Covered over by a tent Sometimes obstructive with decent Balance and posture when you train I’m the Latin little brain The Skull and Cranial Cavity Module 202 - Theme 1 - Lecture 1 Dominic O’Brien MSc, FHEA, PG...

The Skull and Cranial Cavity Module 202 - Theme 1 - Lecture 1 A riddle while you wait: Covered over by a tent Sometimes obstructive with decent Balance and posture when you train I’m the Latin little brain The Skull and Cranial Cavity Module 202 - Theme 1 - Lecture 1 Dominic O’Brien MSc, FHEA, PGCert Pronouns: he/she/they Lecturer in Anatomy D.O’[email protected] Module 202 Anatomy Outline 4 lectures Skull and Cranial Cavity Face, Temporal and Infratemporal Fossa The Orbit and Nasal Cavity The Neck and Oral Cavity 4 DR sessions Mirroring each lecture 1 LAUS session Surface anatomy and ultrasound of the head and neck 2 Optional DR sessions (capped to 50 attendees) Brain removal: 18th Oct 11am - 1pm Face and neck dissection: 29th Nov 11am - 1pm Complete Anatomy Student licence can be redeemed for free - See instructions: Screens used in teaching will be available in the Content section Slido Q&A Area to post anatomy related questions anonymously. Try to make your question as specific as possible. Have a look at previously posted questions to avoid repetition. Accessible through Blackboard. ‘Slido Q&A’ on your module page. Select the relevant ‘room’ e.g. Module 202 Check Slido regularly - you will not get a notification when a question has been answered. No need to sign up/log in Questions can be posted anonymously Open view – all students can see questions/answers posted Join at slido.com #2144458 ⓘ Click instructions Present for with participants Slido or install while our presenting. Chrome extension to display joining Outcomes Understand the arrangement of tissues of the scalp Identify the bones of the skull Distinguish key bony landmarks Surface projections Cranial foramina Describe the blood supply to the head, neck and brain The Scalp Tissues covering the skull superficially Skin Connective tissue (dense) Aponeurosis of occipitofrontalis muscle Loose connective tissue Periosteum of the skull Which layer of the scalp will contain the majority of the blood vessels supplying the tissues of the scalp? ⓘ Start presenting to display the poll results on this slide. Quiz Which layer of the scalp will contain the majority of the blood vessels supplying the tissues of the scalp? A. Aponeurotic B. Dense Connective Tissue C. Loose Connective Tissue D. Periosteal E. Skin Clinical Significance - Scalp Lacerations Lacerations to the scalp will bleed profusely The dense connective tissue layer is unable to retract to its original position - Blood vessels remain open All layers must be closed during suturing The Skull Bony casing which surrounds the brain Two portions Neurocranium Bones surrounding the brain Viscerocranium Facial skeleton Bones join at sutures These form at ~5 years of age Before this cartilaginous structures called fontanelles are present Neurocranium Most bones share a name with the lobe of the brain which they cover Frontal Ethmoid Viscerocranium Palatine Zygoma Mandible Inferior Concha Which bone does not directly suture with the frontal bone? ⓘ Start presenting to display the poll results on this slide. Quiz Which bone does not directly suture with the frontal bone? A. Ethmoid B. Maxilla C. Mandible D. Parietal E. Zygomatic Suture point between the frontal, parietal, temporal and sphenoid Middle Meningeal Artery (MMA) runs deep to it Hydrocephalus Aneurysm / Haemorrhage Clinical Considerations - The Skull Pterion Hydrocephalus Build up of CSF in the skull Presents differently in children and adults Aneurysm / Haemorrhage Hydrocephalus Aneurysm / Haemorrhage - Compromised vasculature Audience Q&A Session ⓘ while Click Present presenting. with Slido or install our Chrome extension to show live Q&A Foramina = small holes Sites of exit and entry to the skull - Veins and cranial nerves exit - Arteries enter Cranial Foramina - Cranial Nerves May be numbered or use roman numerals Number Name 1 / I Olfactory 2 / II Optic 3 / III Oculomotor 4 / IV Trochlear 5 / V Trigeminal V1 Ophthalmic V2 Maxillary V3 Number Name 6 / VI Abducens 7 / VII Facial 8 / VIII Vestibulocochlear 9 / IX Glossopharyngeal 10 / X Vagus 11 / XI Accessory 12 / XII Hypoglossal Foramina Contents 1. Cribriform plate CN 1 2. Optic Canal CN 2, Ophthalmic artery 3. Superior Orbital Fissure CN 3,4,6, 5 (V1) 4. Rotundum CN5 V2 5. Ovale CN 5 V3, AMMA 6. Spinosum Middle Meningeal Artery 7. Lacerum *Carotid Artery 8. Internal Acoustic Meatus CN 7 and 8 9. Jugular foramen CN 9, 10, 11, IJV 10. Hypoglossal Canal CN12 11. Magnum Spinal Cord The olfactory nerve (CN I) is responsible for conveying special sensory information. Which sense is this nerve responsible for? ⓘ Start presenting to display the poll results on this slide. Quiz The olfactory nerve (CN I) is responsible for conveying special sensory information. Which sense is this nerve responsible for? A. Balance B. Hearing C. Smell D. Taste E. Touch Blood Supply to the Brain Supplied by two main arteries: Internal carotid artery Vertebral artery The branches anastomose to form the Cerebral Arterial Circle - Also known as the Circle of Willis Vertebral arteries enter at the foramen magnum where they unite to form the basilar artery. Blood Supply to the Brain Common carotid lies deep to sternocleidomastoid Useful pulse palpation point Internal carotid supplies the brain External carotid supplies the face Cerebral Arterial Circle Also known as the Circle of Willis Formed by an anastomosis between: - 2 Internal Carotid arteries (ICA) - 2 Vertebral arteries These anastomoses allow for collateral circulation Cerebral Arterial Circle Gives rise to the cerebral arteries Anterior Middle Posterior Cerebral Arteries The anterior cerebral artery: - supplies the medial and superior surfaces of the brain and frontal pole. The middle cerebral supplies: - the lateral surfaces and temporal pole. The posterior cerebral supplies: - the inferior surfaces and occipital pole. Clinical Consideration - Stroke Strokes are caused by an embolism in a cerebral artery. No anastomoses of cerebral arteries once within the brain No way to avoid ischaemia Hence neurological deficit The area of the brain supplied by the vessel will affect what these deficits will be A. CT scan. B. T2- weighted MRI. The middle cerebral artery is most commonly involved in strokes. What portion of the brain does this artery supply? ⓘ Start presenting to display the poll results on this slide. Quiz The middle cerebral artery is most commonly involved in strokes. What portion of the brain does this artery supply? A. Anterior B. Inferior C. Lateral D. Posterior E. Rostral Audience Q&A Session ⓘ while Click Present presenting. with Slido or install our Chrome extension to show live Q&A Further Reading Gray’s Anatomy for Students - Ideal for diagrams and explanations McMinn’s and Abraham’s Clinical Atlas of Human Anatomy - Cadaveric image atlas - great DR prep Neuroanatomy - An Illustrated Colour Text - Concise neuroanatomy explanations with great diagrams However, if you have any questions, concerns or feedback, please feel free to get in touch: D.O’[email protected] or you can provide feedback anonymously through Qualtrics Dominic O’Brien - Qualtrics Feedback Survey Covered over by a tent Sometimes obstructive with decent Balance and posture when you train I’m the Latin little brain Cerebellum