Mild Traumatic Brain Injury

Andy Jagoda, MDProfessor of Emergency MedicineMount Sinai School of Medicine

New York, New York

Andy Jagoda, MD

The Case

A 60-year-old driver is in a head-on collision at approximately 25 km/h. She is not wearing a seat belt and strikes her head on the windshield and sustains a forehead laceration. She has less than one minute of loss of consciousness. She is taken to the ED where she is alert and oriented. She has no past medical history and is on no medications.

Andy Jagoda, MD

Questions:

• Is there a role for plain film radiographs in patients with head injury?

• Which patients with head injury need to have a head computed tomogram (CT)?

• Are there predictors of who will develop the postconcussive syndrome?

Andy Jagoda, MD

Which of the Following is Not Used to Define Mild TBI?

a. GCS >12

b. Loss of consciousness <1 hr

c. Post-traumatic amnesia <24 hrs

d. Non-focal neurologic exam

e. CT scan

Andy Jagoda, MD

What is the best initial test in the presented case of a patient who had

loss of consciousness and a forehead laceration?

a. Skull radiographs

b. Non-contrast CT

c. Contrast CT

d. MRI

e. PET

Andy Jagoda, MD

a. 0%

b. 5%

c. 50%

d. 75%

e. 100%

What per cent of head trauma patients with an intracranial lesion on head CT have normal skull x-rays?

Andy Jagoda, MD

What is the GCS score of a patient who keeps his eyes closed but opens them to questions; answers questions with difficulty and is

confused; moves extremities appropriately on command?

a. 15a. 15

b. 13b. 13

c. 11c. 11

d. 09d. 09

e. 07e. 07

Andy Jagoda, MD

A. PCS occurs primarily in men

B. Early PCS occurs primarily in patients withpsychiatric problems

C. Early PCS occurs more frequently in patients involved in litigation

D. PCS occurs in up to 20% of patients

E. anxiety, stress, and depression have been linked to late

Postconcussive syndrome (PCS) in mild TBI, which of the following is true?

Andy Jagoda, MD

Epidemiology

• 6 million head injury cases in the USA each year (1 in 45)– Young male predominance

• 1.1 million ED evaluations (1-2%)• 250,000 hospitalizations (1 in 1000)• 60,000 deaths (1 in 5000)• Most cases are classified as mild

Andy Jagoda, MD

Pathophysiology

• Deceleration / rotation injury• Blood vessel disruption

– Petechial hemorrhage– Focal edema– Disruption of bridging veins

• Intra-axonal neurofilament organization / axonal swelling

• Secondary injury– Excitatory amino acids– Oxygen free radicals

Andy Jagoda, MD

Diagnosing Mild TBIMild TBI Committee of the American Congress of Rehabilitation Medicine

• Alteration in mental state at time of the accident

• LOC <30 min

• After 30 min, GCS 13-15

• Amnesia <24 hours

Andy Jagoda, MD

Classification - GCS

• Eyes– 4 opens spontaneously– 3 opens to verbal– 2 opens to pain– 1 do not open

• Verbal– 5 oriented– 4 confused– 3 inappropriate– 2 incomprehensible– 1 none

• Motor– 6 obeys– 5 localizes– 4 withdraws– 3 abnormal flex– 2 extensor response– 1 none

• Scoring– Mild >12– Moderate 9-12– Severe <9

Andy Jagoda, MD

Classification - GCS - Mortality

• Developed for prognosis in severe TBI• Timing of score is not standardized• One score not sufficient - perform serial

exams– Prognosis worse if score does not improve or

if it worsens

• Does not account for drugs, seizures, or metabolic problems

Andy Jagoda, MD

Classification - GCS - Mortality

• Severe = 40%– 3 = 80%

– 4 = 55%

– 5 = 40%

• Moderate = 12%

• Mild = 01%

Andy Jagoda, MD

Use of CT in Diagnosing MTBI

• Retrospective study, 215 hospitalized patients– Mild TBI without complications– Mild TBI with complications (positive CT)– Moderate TBI

• Mild TBI patients with positive CT performed on neuropsychiatric testing like moderate TBI

• Moderate group had worse function at 6 months• Length of LOC or amnesia did not differentiate mild

from moderate groups• Depressed skull fractures without parenchymal lesions

performed as mild TBI

Williams et al. Williams et al. Neurosurgery Neurosurgery 1990;27:422.1990;27:422.

Andy Jagoda, MD

Skull Radiographs and Intracranial Lesions

• Retrospective review

• 207 hospitalized patients with intracranial lesions

• 63% had no skull fracture

• Skull films do not predict intracranial lesion

Cooper P, Ho V. Cooper P, Ho V. Neurosurgery Neurosurgery 1983;13:1361983;13:136

Andy Jagoda, MD

• Retrospective review 22,058 cases

• Patients with skull fractures, 91% did not have intracranial injury

• 51% of patients with intracranial injury did not have a skull fracture

Masters et al. Masters et al. NEJMNEJM 1987;316:84-91 1987;316:84-91

Skull Radiographs and Intracranial Lesions

Andy Jagoda, MD

Skull Radiographs and Intracranial Lesions

• Prospective study: 7035 patients – Not all patients received same tests– 48% lost to follow-up

• Skull fracture did not predict an intracranial injury

• Absence of a skull fracture did not rule out an intracranial injury

• Plain films are neither sensitive nor specific for intracranial injury

Masters et al. Masters et al. NEJMNEJM 1987;316:84-91 1987;316:84-91

Andy Jagoda, MD

Low Risk Group For Intracranial Injury

• Asymptomatic• Headache• Dizziness• Scalp hematoma, laceration, contusion• Absence of LOC or amnesia• No patients with neurologic deterioration

identified• No imaging study indicated

Masters et al. Masters et al. NEJMNEJM 1987;316:84-91 1987;316:84-91

Andy Jagoda, MD

Moderate Risk Group For Intracranial Injury

• Loss of consciousness• Unreliable history• Progressive headache• Alcohol or drug intoxication• Age less than 2 years• Post traumatic seizure• BSF / multiple trauma / possible

penetrating trauma• CT scan recommended

Masters et al. Masters et al. NEJMNEJM 1987;316:84-91 1987;316:84-91

Andy Jagoda, MD

Head CT In Mild TBI

• Retrospective review 1538 trauma admissions• GCS > 12; all with history of LOC or amnesia• 265 (17.2%) had intracranial lesion:

– GCS 13: 37.5%– GCS 14: 24.2%– GCS 15: 13.2%

• 58 (3.8% of total 22% of patients with positive CT) required neurosurgery

• No patient with a normal CT deteriorated

Stein S, Ross S. Stein S, Ross S. Ann Emerg MedAnn Emerg Med 1993;22:1193 1993;22:1193

Andy Jagoda, MD

Head CT In Mild TBI

• Prospective study: 712 consecutive ED patients• GCS 15; history of LOC or amnesia• Nonfocal neurologic exam

– 4 object recall and digit span testing

• 67 (9.4%) had a positive head CT• 2 (.28%) required emergent neurosurgery• No statistical model could be created to classify

95% of patients into CT normal vs abnormal

Jeret et al. Jeret et al. Neurosurgery Neurosurgery 1993;32:91993;32:9

Andy Jagoda, MD

Head CT in Mild TBI

• Prospective study in patients with a GCS of 15• Phase 1: 520 patients to create 7 criteria:

(headache, vomiting, age over 60, intoxication, memory deficits, evidence of trauma, seizure)

• Phase 2: 909 patients: Criteria found to be 100% sensitive; 100% negative predictive value

• 1429 pts: 6.5% + CT; 0.4% required neurosurgery

• Criteria would have resulted in a 22% decrease in the number of scans ordered

Haydel et al. Haydel et al. NEJMNEJM 2000; 343:100-105 2000; 343:100-105

Andy Jagoda, MD

Head CT In Mild TBI • 10% to 20% have a positive CT• .2 to 4% have a neurosurgical lesion• Patients without LOC or amnesia, normal exam,

and GCS 15 do not need imaging– Direct trauma to the temporal area– Children <3 years

• In patients with a GCS of 15, historical and clinical criteria can be used to determine need for CT

• Patients with a normal CT can be safely discharged home

Andy Jagoda, MD

Magnetic Resonance Imaging

• Prospective study• 50 TBI patients; CT, MRI, neuropsych • 72% had lesions on CT / 80% on MRI• MRI identified additional lesions in 52% of

patients with lesions on CT• No correlation with size of lesions and

length of LOC: inconsistent relationship between lesions and neuropsych findings

Levin et al. J Neurol Neurosurg Psych 1992;55:255

Andy Jagoda, MD

Postconcussive Syndrome (PCS)

• Prospective study, 538 patients• MTBI, hospitalized• 3 month follow-up• 79% headaches• 59% memory dysfunction• 33% had not returned to work• Ongoing litigation did not correlate with

complaints

Rimel et al. Rimel et al. NeurosurgeryNeurosurgery 1981;9:221 1981;9:221

Andy Jagoda, MD

PCS: Reading the Literature

• Symptom complex related to TBI– Somatic

• Headache, sleep disturbance, dizziness, nausea, fatigue, sensitivity to light / sound

– Cognitive• Attention / concentration problems, memory problems

– Affective• Irritability, anxiety, depression, emotional lability

• Incidence in MTBI patients:– 80% at 1 month– 30% at 3 months– 15% at 12 months

Andy Jagoda, MD

PCS: Reading the Literature

• Lack of uniformity in definitions

• Selection bias

• No controls

• No pre-injury baseline

• Lack of standardization of testing

• Attrition in follow-up

Andy Jagoda, MD

Postconcussive Syndrome

• 587 hospitalized, uncomplicated MTBI patients

• Prospective over 1 year (68% lost to follow-up)

• At discharge, 67% had at least one symptom

• 38% had symptoms at 3 months

• 23% had symptoms at 6 months

• 13% had symptoms at 12 months

• Presence of symptoms at hospital discharge were not predictive of symptoms at 3 months

Alves et al. Alves et al. J Head Trauma RehabJ Head Trauma Rehab 1993;8:48 1993;8:48

Andy Jagoda, MD

PCS: Neuropsychiatric Testing

• No consensus on tests• Testing focuses on cognitive function:

– Attention– Information processing– Choice reaction time

• Testing demonstrates clear deficits in the first 3 months that appear independent of psychosocial factors

• Persistence of symptoms after 3 months appears to be complicated by psychosocial factors

Andy Jagoda, MD

Prognostic Predictors Of PCS

• Best prognosis– Young– Male– Educated– Social support

• Worse prognosis– Elderly– Female– Social / physical stressors– Substance abuse

Andy Jagoda, MD

Disposition• Saunders et al. Ann Emerg Med 1986;15:160.

– 47 consecutive MTBI discharged from the ED– No patient could remember more than 2 of the 8 items

on the home care discharge instructions– 20% denied ever having received instructions– Third party involvement improved compliance with

instructions to 67%

• Levitt et al. Amer J Emerg Med 1994;12:172.– 23% of MTBI patients discharged from the ED could not

remember any of their discharge instructions

• Studies emphasize importance of involving third parties in discharge process

Andy Jagoda, MD

Which of the Following is Not Used to Define Mild TBI?

• a. GCS >12

• b. Loss of consciousness <1 hr

• c. Post-traumatic amnesia <24 hrs

• d. Non-focal neurologic exam

• e. CT scan

Andy Jagoda, MD

What is the best initial test in the presented case of a patient who

had loss of consciousness and a forehead laceration?

a. Skull radiographs

b. Non-contrast CT

c. Contrast CT

d. MRI

e. PET

Andy Jagoda, MD

What per cent of head trauma patients with an intracranial lesion on head CT have normal skull x-rays?

a. 0%

b. 5%

c. 50%

d. 75%

e. 100%

Andy Jagoda, MD

What is the GCS score of a patient who keeps his eyes closed but opens them to questions; answers questions with difficulty and is

confused; moves extremities appropriately on command?

a. 15

b. 13

c. 11

d. 09

e. 07

Andy Jagoda, MD

Postconcussive syndrome (PCS) in mild TBI, which of the following is true?

A. PCS occurs primarily in men.

B. Early PCS occurs primarily in patients with psychiatric problems

C. Early PCS occurs more frequently in patients involved in litigation

D. PCS occurs in up to 20% of patients

E. Anxiety, stress, and depression have been linked to late PCS

Andy Jagoda, MD

Conclusions

• X-rays have low sensitivity and specificity for intracranial injury and are not indicated

• .2% - 4% of mild TBI pts have a neurosurgical lesion

• 10% - 20% of mild TBI patients have abnormalities on non-contrast head CT

• Patients with a normal CT can be safely discharged home

• 80% after a mild TBI develop symptoms of PCS and should be properly counseled