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Mild traumatic brain injury

Last reviewed: 4 Nov 2023
Last updated: 18 Nov 2022



History and exam

Key diagnostic factors

  • direct blow to the head or deceleration of the head from an impulsive force
  • previous brain trauma, substance use, or alcohol misuse
More key diagnostic factors

Other diagnostic factors

  • headache
  • feeling foggy/slow
  • dizziness/balance problems
  • memory difficulties
  • vomiting/nausea
  • neck pain
  • normal physical neurologic exam
  • abnormalities on neuropsychological testing
Other diagnostic factors

Risk factors

  • head injury
  • previous brain trauma
  • alcohol and drug misuse
  • poor neck strength
More risk factors

Diagnostic investigations

1st investigations to order

  • CT head
More 1st investigations to order

Investigations to consider

  • MRI head
More investigations to consider

Emerging tests

  • PET, single-photon emission CT (SPECT) of head
  • multimodal MRI technologies

Treatment algorithm


all patients



Luke C. Henry, PhD
Luke C. Henry

Assistant Professor

Department of Neurological Surgery

Senior Clinical Neuropsychologist

University of Pittsburgh




LCH declares that he has no competing interests.

Maria Twichell, MD

Assistant Clinical Professor


General Rehabilitation Unit

UPMC Physical Medicine and Rehabilitation

University of Pittsburgh Medical Center




MT declares that she has no competing interests.


Dr Luke C. Henry and Dr Maria Twichell would like to gratefully acknowledge Dr Jeffrey Bazarian and Dr Maryse Lassonde, previous contributors to this topic.


JB has been reimbursed by Roche, the manufacturer of an automated assay for serum S-100B, to attend a conference, and has been reimbursed by Banyan Biomarkers and Neuren Pharmaceuticals to help develop their research protocols. JB is also an author of a reference cited in this topic. ML is an author of several references cited in this topic.

Peer reviewers

Eirik Helseth, MD, PhD

Professor and Consultant

Department of Neurosurgery

Ulleval University Hospital




EH declares that he has no competing interests.

Margot Putukian, MD

Director of Athletic Medicine

Princeton University




MP is an author of a reference cited in this topic.

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