What are the key topics in the anatomy of Traumatic Brain Injury (TBI)?

From the Guidelines

Understanding the anatomy of traumatic brain injury (TBI) is crucial for assessing injury severity and guiding treatment approaches, with key structures including the skull, meninges, brain parenchyma, cerebral vasculature, ventricular system, and brainstem. The anatomy of TBI involves several critical components that contribute to the complexity of the injury.

• The skull and meninges play a significant role in protecting the brain, but they can also contribute to injury mechanisms, as the rigid cranium limits expansion during swelling and the dura, arachnoid, and pia maters can be damaged during trauma 1.
• Brain parenchyma, comprising gray matter (neuronal cell bodies) and white matter (axonal tracts), is particularly vulnerable to injury forces, with different responses to trauma in these distinct tissue types.
• The cerebral vasculature is critical, as damage can cause various types of hemorrhage (epidural, subdural, subarachnoid, or intraparenchymal) and disrupt blood-brain barrier function, leading to further injury and complications 1.
• The ventricular system, responsible for cerebrospinal fluid dynamics, may be damaged, potentially causing hydrocephalus and altering intracranial pressure (ICP) management.
• Brainstem injuries are especially concerning due to their control of vital functions, and understanding the anatomy of these structures is essential for predicting outcomes and guiding treatment approaches. The complex interplay between primary injury (direct trauma) and secondary injury (cascading biochemical processes) across these anatomical structures determines the ultimate impact of TBI on neurological function, as highlighted in recent consensus recommendations for targeted temperature control following TBI 1.

From the Research

Important Topics in TBI Anatomy

The anatomy of Traumatic Brain Injury (TBI) involves various brain structures and regions. Some of the key topics include:

• Frontal and Temporal Lobes: These areas are frequently damaged in closed head injuries 2
• Deep Cortical Structures: The hippocampus, amygdala, and basal ganglia are also affected in TBI, with significant volume loss observed in these regions 3
• Hippocampus: This structure is particularly vulnerable to damage, with diffuse rather than focal damage observed in some cases 3
• Midbrain, Cerebellum, and Mesial Temporal Lobe: These areas are also prone to injury, with strain concentration driving the anatomical distribution of injury in acute and chronic TBI 4
• Interface between Cortex and White Matter: This region is also susceptible to injury, particularly at sulcal depths 1-12 4
• Blood-Brain Barrier (BBB): Disruption of the BBB is a common feature of TBI, leading to brain edema and the discharge of immune mediators 5

Regional Patterns of Injury

Different regional patterns of injury are observed in TBI, including:

• Focal Hippocampal Abnormalities: Lesions in the hippocampus can occur, but diffuse damage is also possible 3
• Axonal Damage, Contusions, and Hemorrhage: These types of tissue damage can occur in various brain regions 5
• Cognitive and Behavioral Disturbances: Frontal lobe lesions can lead to cognitive deficits and behavioral disturbances, including changes in cognition, decision-making, memory, attention, and speech capability 2, 5