Nontraumatic brain injury

Nontraumatic brain injury (NTBI) is a broad category of brain disorders not resulting from traumatic forces. Included in this category are acquired brain injuries resulting from ischemic cerebrovascular disease, infection, neoplasm, and autoimmune disorders ( Table 53.1 ). These pathologies result in impairments of physical function, cognition, language, and behavior. Evaluation for these disorders includes comprehensive history and physicals with symptomatology dependent on location of lesion and degree of injury/inflammation ( Table 53.2 ). Treatment involves supportive care, rehabilitation, and education in addition to addressing specific brain issues ( Table 53.3 ). In general, the NTBI population is an older demographic with more comorbidities that those with traumatic brain injury (TBI). Functional recovery after TBI tends to be better than after NTBI.

TABLE 53.2

Clinical Evaluation

History and Physical Items

Labs and Tests

Imaging

Ischemia

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Emphasis on cardiovascular and neurological history, physical examination, and review of systems
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Time of onset is important for early intervention

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Delineate stroke risk factors (see Table 53.3 )

TABLE 53.3

Treatment

Disorder	Treatment
Ischemia	• Thrombolysis with tissue plasminogen activator • Thrombectomy/embolectomy • Oral Antiplatelet • HMG-CoA reductase inhibitor • Addressing modifiable risk factors
Infection	• Oral or intravenous (IV) antimicrobial • Neurosurgical drainage/decompression • Vaccination
Tumors ^,	• Neurosurgical resection • Radiation • Chemotherapy
Autoimmune	• Steroids • IV immunoglobulin • Plasmapheresis • Immunosuppressant drugs (e.g., methotrexate, cyclophosphamide, Plaquenil)

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Complete blood counts (CBC)
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Basic Metabolic Panel (BMP)
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Lipid panels
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Liver function tests
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Hemoglobin A1c
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Hypercoagulability panel (antiphospholipid antibody panel, protein C and S, factor V Leiden)
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Echocardiogram
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Electrocardiogram

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Preferred initial: computerized tomography (CT) of the brain without contrast
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CT can be negative in the first 24 h and helps rule out hemorrhage to direct use of thrombolytic therapy.
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Magnetic resonance imaging (MRI) is used to confirm and/or identify subtle strokes
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Angiography is an adjunct to CT and MRI and identifies areas of vascular abnormality and voids in blood flow

Infection

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Signs/symptoms: fever, headache, nausea, vomiting, vision changes, drowsiness, photosensitivity, and stiff neck
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Behavioral changes and confusion can be seen.
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Initially presents with flulike syndrome
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Rash may be seen in bacterial meningitis

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CBC
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BMP
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Blood cultures
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Cerebrospinal fluid (CSF) analysis and culture
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Viral serology

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MRI with contrast is preferred
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Imaging may be negative in meningitis and encephalitis
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Meningitis: imaging detects potential entry point of infection
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Abscess: MRI with contrast may show an encapsulated mass with necrotic center

Tumors ^,

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Signs/symptoms: headache, confusion, nausea, vomiting, weakness, balance impairment, cranial nerve palsies, fever, weight loss
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Headache is the most common symptom
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Seizure is a common presenting sign

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CBC
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BMP
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CSF analysis
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Serum tumor markers
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Biopsy

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CT and MRI of brain and body
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MRI with gadolinium contrast is preferred modality (look for enhancement with central necrosis and surrounding edema)

Autoimmune

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Fatigue, headache, seizures, stroke, and cranial nerve palsies are common
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Relapsing, remitting, and progressive
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Past medical and family history of autoimmune disease
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Examination findings can include skin findings such as rash, purpura

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CBC
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BMP
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Blood cultures
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CSF analysis and culture
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Autoantibodies N-methyl-D-aspartate (NMDA) receptor
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Brain biopsy

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CT and MRI
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CT angiography is helpful in cerebral vasculitis and can show alternating areas of stenosis causing a beading-type appearance of the blood vessel

Ischemia

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Focal ischemia is the most common stroke and is categorized into three types ( Table 53.4 ). Symptoms lasting less than 24 hours are transient ischemic attacks (TIAs) and greater than 24 hours qualify as a stroke.

TABLE 53.4

Ischemic Stroke Classification

Thrombotic	Embolic	Lacunar
Large cerebral vessel occlusions	Cardioembolic	Smaller, arteriolar vessel occlusion
Gradual onset, progressive symptoms; often preceded by transient ischemic attack	Sudden in onset	Presents suddenly or gradually