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Diffuse Axonal Injury

Updated : February 21, 2024





Background

Diffuse Axonal injury (DAI) results from traumatic brain injury (TBI) caused by blunt force or injury to the brain. The white matter tracts in the brain are most affected by diffuse axonal injury; patients with such injury exhibit neurological dysfunction, which could range from a moderate to severe impairment and generally result in coma or death.

Epidemiology

According to the Centers for Disease Control and Prevention (CDC), approximately 1.5 million traumatic brain injury cases are recorded yearly in the United States. Traumatic brain injury is the most common cause of mortality and disability among children and young adults in the United States. DAI’s prevalence rate remains undefined. Although, it is estimated that around 10% of TBI patients hospitalized have DAI to some degree.

Patients with confirmed DAI are estimated to have a 25% of mortality rate. This prevalence may be underestimated in patients with conditions such as epidural hematomas, subdural hematoma, and other types of TBI who do not possess an accurate diagnosis. As per the autopsy findings, patients with severe traumatic brain injury develop considerable occurrence of Diffuse axonal damage.

Anatomy

Pathophysiology

DAI causes neuronal connections to break down or become fragmented, which impacts numerous functional parts of the brain. Patients with DAI usually exhibit dysfunction in the bilateral neurological investigation of the corpus callosum, brainstem, frontal, and temporal white matter.

The severity of the disease can also be indicated by the Glasgow coma scale (GCS), which indicates the impairment or neurological dysfunction in any TBI. The clinical presentation and pathophysiological lesions in the white matter pathways are incorporated in the Adams classification of diffuse axonal damage (1-3 grades)

Grade 1: Mild DAI with minor white matter changes to the cerebral cortex, cortex callosum, and the brainstem.

Grade 2: Moderate DAI with gross focal lesion in corpus callosum.

Grade 3: Severe DAI with gross focal lesion in corpus callosum and brainstem.

Etiology

Angular or rotational acceleration-deacceleration forces acting on the skull result in stretching of the brain tissue and lead to parallel force to the white matter tracts of the brain.

Diffuse axonal damage is most frequently caused by high-speed vehicle collisions, which results in damage to the axons at the intersection of the grey and white matter of the brain. The commonly impacted region in DAI is the corpus callosum and the brainstem.

Genetics

Prognostic Factors

The prognosis of this condition is poor. In case of severe DAI and surgical intervention, prolonged rehabilitative therapies such as physical, occupational, speech, and psychosocial are required.

Clinical History

Physical Examination

Age group

Associated comorbidity

Associated activity

Acuity of presentation

Differential Diagnoses

Laboratory Studies

Imaging Studies

Procedures

Histologic Findings

Staging

Treatment Paradigm

by Stage

by Modality

Chemotherapy

Radiation Therapy

Surgical Interventions

Hormone Therapy

Immunotherapy

Hyperthermia

Photodynamic Therapy

Stem Cell Transplant

Targeted Therapy

Palliative Care

Medication

Media Gallary

References

https://www.ncbi.nlm.nih.gov/books/NBK448102/

Diffuse Axonal Injury

Updated : February 21, 2024




Diffuse Axonal injury (DAI) results from traumatic brain injury (TBI) caused by blunt force or injury to the brain. The white matter tracts in the brain are most affected by diffuse axonal injury; patients with such injury exhibit neurological dysfunction, which could range from a moderate to severe impairment and generally result in coma or death.

According to the Centers for Disease Control and Prevention (CDC), approximately 1.5 million traumatic brain injury cases are recorded yearly in the United States. Traumatic brain injury is the most common cause of mortality and disability among children and young adults in the United States. DAI’s prevalence rate remains undefined. Although, it is estimated that around 10% of TBI patients hospitalized have DAI to some degree.

Patients with confirmed DAI are estimated to have a 25% of mortality rate. This prevalence may be underestimated in patients with conditions such as epidural hematomas, subdural hematoma, and other types of TBI who do not possess an accurate diagnosis. As per the autopsy findings, patients with severe traumatic brain injury develop considerable occurrence of Diffuse axonal damage.

DAI causes neuronal connections to break down or become fragmented, which impacts numerous functional parts of the brain. Patients with DAI usually exhibit dysfunction in the bilateral neurological investigation of the corpus callosum, brainstem, frontal, and temporal white matter.

The severity of the disease can also be indicated by the Glasgow coma scale (GCS), which indicates the impairment or neurological dysfunction in any TBI. The clinical presentation and pathophysiological lesions in the white matter pathways are incorporated in the Adams classification of diffuse axonal damage (1-3 grades)

Grade 1: Mild DAI with minor white matter changes to the cerebral cortex, cortex callosum, and the brainstem.

Grade 2: Moderate DAI with gross focal lesion in corpus callosum.

Grade 3: Severe DAI with gross focal lesion in corpus callosum and brainstem.

Angular or rotational acceleration-deacceleration forces acting on the skull result in stretching of the brain tissue and lead to parallel force to the white matter tracts of the brain.

Diffuse axonal damage is most frequently caused by high-speed vehicle collisions, which results in damage to the axons at the intersection of the grey and white matter of the brain. The commonly impacted region in DAI is the corpus callosum and the brainstem.

The prognosis of this condition is poor. In case of severe DAI and surgical intervention, prolonged rehabilitative therapies such as physical, occupational, speech, and psychosocial are required.

https://www.ncbi.nlm.nih.gov/books/NBK448102/