Lecture: Intracranial Hemorrhages

Overview

• Intracranial Hemorrhages: Focus on the different types and their association with the meninges.
• Meninges Anatomy: Essential connective tissue layers covering the CNS (Central Nervous System).
  • Order (Deep to Superficial): Brain substance -> Pia Mater -> Subarachnoid space -> Arachnoid Mater -> Subdural space -> Dura Mater (Meningeal Layer -> Periosteal Layer) -> Epidural space.

Meninges and Related Spaces

• Pia Mater: Clings to brain and spinal cord, interacts with astrocytes.
• Subarachnoid Space: Contains cerebrospinal fluid (CSF).
• Arachnoid Mater: Contains arachnoid granulations/villi and trabeculae.
• Subdural Space: Between arachnoid mater and meningeal layer of dura mater.
• Dura Mater: Two layers - Meningeal (inner) and Periosteal (outer).
  • Dural Sinuses: Veins that run between separated dural layers.
  • Dural Septa: Protects dural sinuses, examples include Falx Cerebri, Tentorium Cerebelli.

Types of Hemorrhages

Epidural Hematoma

• Location: Epidural space.
• Cause: Temporal bone fracture, often injuring middle meningeal artery.
• Symptoms: Loss of consciousness, lucid interval, rapid decline.
• Diagnosis: CT scan shows biconvex/lens-shaped hematoma.
• Management: Evacuate hematoma if necessary; manage intracranial pressure with mannitol, head elevation, or hyperventilation.

Subdural Hematoma

• Location: Subdural space.
• Cause: Trauma, falls, usually from shearing of bridging veins.
• Symptoms: Headaches, high BP, confusion; no lucid interval.
• Diagnosis: CT scan shows crescent/concave hematoma.
• Management: Evacuate if midline shift >5mm.

Subarachnoid Hemorrhage

• Location: Subarachnoid space.
• Cause: Ruptured berry aneurysms.
• Symptoms: "Thunderclap" headache, neck stiffness, photophobia.
• Diagnosis: CT scan; follow with four-vessel angiography if positive.
• Management: Supportive care, manage BP, surgical coiling for severe cases.

Intracerebral Hemorrhage

• Location: Various regions including thalamus, basal ganglia.
• Cause: Hypertension, amyloidosis, AVM.
• Symptoms: Headaches, nausea, hemiparesis, loss of consciousness.
• Diagnosis: CT scan; avoid lumbar puncture if suspected.
• Management: Manage intracranial pressure, evacuate if mass effect evident.

Important Notes

• Avoid lumbar puncture in suspected intracerebral or subarachnoid hemorrhages.
• Recognize terms such as lucid intervals, concave hematoma, and biconvex hematoma for accurate diagnosis.

Review and Further Study

• Understand the relationship between the anatomical structures and the potential spaces where these hemorrhages occur.
• Review the specific symptoms and management strategies for each type of hemorrhage.
• Familiarize with diagnostic imaging signs such as the CT appearance of different hematomas.