Cranium, Meninges, Ventricles, & CSF, Spinal Cord, Blood Supply

🧠 CRANIUM & FOSSAE

Q: What is the main function of the cranium?

A: Protects the brain and supports cranial nerves and vessels.

🧠 CRANIUM & FOSSAE

Q: What passes through the foramen magnum?

A: Brainstem → spinal cord connection, vertebral arteries, spinal root of CN XI.

🧠 CRANIUM & FOSSAE

Q: Name the three cranial fossae and their contents.

A:

• Anterior: Frontal lobes

• Middle: Temporal lobes

• Posterior: Cerebellum, pons, medulla

💡 Mnemonic: “Front-Temp-Post = Frontal, Temporal, Pons”

🩹 MENINGES

Q: What are the three meningeal layers (outer → inner)?

A: Dura mater → Arachnoid mater → Pia mater.

🩹 MENINGES

Q: Function of the dura mater?

A: Tough outer layer with venous sinuses that drain brain blood.
Structures: Falx cerebri, Tentorium cerebelli.

🩹 MENINGES

Q: Function of the arachnoid mater?

A: Holds CSF in the subarachnoid space; reabsorbs it via arachnoid villi.

🩹 MENINGES

Q: Function of the pia mater?

A: Adheres directly to brain surface; carries blood to neural tissue.

💡 Mnemonic: DAP = Dura, Arachnoid, Pia (from outer to inner)
💬 Tip: Think “Durable, Airy, Plastic wrap” for how they feel and function.

💧 VENTRICLES & CSF

Q: Where is CSF produced?

A: Choroid plexus (mainly in lateral ventricles).

💧 VENTRICLES & CSF

Q: CSF pathway in order?

A:
Lateral ventricles → Foramen of Monro → Third ventricle →
Cerebral aqueduct → Fourth ventricle →
Foramen of Magendie & Luschka → Subarachnoid space →
Arachnoid villi → Venous sinuses.

💡 Mnemonic: “L-M-3-A-4-M/L-S-A” → (Lateral, Monro, 3rd, Aqueduct, 4th, Magendie/Luschka, Subarachnoid, Absorbed)

💧 VENTRICLES & CSF

Q: Functions of CSF?

A: Cushions brain, circulates nutrients, removes waste, stabilizes pressure.

💧 VENTRICLES & CSF

Q: What is hydrocephalus?

A: Abnormal CSF buildup due to overproduction, blockage, or poor absorption.

💧 VENTRICLES & CSF

Q: Pediatric vs adult hydrocephalus key signs?

A:

Child: Enlarged head, pressure, developmental delay.

Adult: Gait issues, incontinence, cognitive decline (normal pressure hydrocephalus).

🧬 SPINAL CORD

Q: Where does the spinal cord begin and end?

A: Begins at foramen magnum → ends near L1–L2.

🧬 SPINAL CORD

Q: How many spinal nerve pairs exist?

A: 31 (8C, 12T, 5L, 5S, 1Coccygeal).

🧬 SPINAL CORD

Q: Primary function?

A: Conducts sensory and motor info between brain and body.

💬 SLP Relevance: Damage can impair respiration → voice/speech issues.

🩸 BLOOD SUPPLY OF THE BRAIN

Q: What are the two main arterial systems?

A:

Internal carotid arteries → anterior circulation

Vertebral arteries → posterior circulation (join to form basilar artery)

🩸 BLOOD SUPPLY OF THE BRAIN

Q: What are the main cerebral arteries?

A: ACA, MCA, PCA.

🩸 BLOOD SUPPLY OF THE BRAIN

Q: What does the Circle of Willis do?

A: Provides collateral blood flow between anterior and posterior circulation.

💡 Mnemonic: “AC-PC IC-PC” → (Anterior cerebral, Posterior cerebral, Internal carotid, Posterior communicating)

💬 SLP Tip:

Left MCA stroke

→ Aphasia

💬 SLP Tip:

Right MCA stroke

→ Pragmatic and prosody deficits

💬 SLP Tip:

Cerebellar lesion

→ Ataxic dysarthria

💬 SLP Tip:

Brainstem lesion

→ Flaccid dysarthria

⚡ WATERSHED ZONES

Q: What are watershed zones?

A: Border regions between major artery territories; prone to ischemia during low blood flow.

⚡ WATERSHED ZONES

Q: Why are they clinically important?

A: Damage can cause cognitive or language deficits even without a large stroke.

💡 Mnemonic: “Between streams, function drains”

❤️ CLINICAL TAKEAWAYS FOR SLPs

CSF disorders:

↑ intracranial pressure → cognitive/communication slowing.

❤ CLINICAL TAKEAWAYS FOR SLPs

MCA stroke:

Expect language + motor speech deficits.

❤ CLINICAL TAKEAWAYS FOR SLPs

Cerebellar/brainstem damage:

Dysarthria types vary (ataxic vs flaccid).

❤ CLINICAL TAKEAWAYS FOR SLPs

Spinal cord lesions:

Reduced breath support affects phonation.

❤ CLINICAL TAKEAWAYS FOR SLPs

Blood flow understanding:

Predicts lesion impact & guides therapy planning.