Posttraumatic Vertigo and Dizziness
Postconcussion syndrome includes persistence of at least three of the following symptoms after a concussion: headache, dizziness, irritability, reduced concentration, fatigue, insomnia, and photophobia and phonophobia. The term postconcussion dizziness implies it is a component of postconcussion syndrome, an entity with a long history. However, in a patient with a history of minor head trauma, it may be unclear whether the individual has dizziness due to microstructural abnormalities from trauma due to the postconcussive syndrome—without any actual injury to the brain—or whether there is actually an unrecognized labyrinthine cause. Indeed, the possibilities are not mutually exclusive; some patients with postconcussive dizziness may also have a labyrinthine cause, thus posing a particular challenge to clinicians. The diagnosis of posttraumatic dizziness is sometimes used to lump all entities together by simply indicating that the patient reports dizziness after a minor head injury.
Patients with mTBI often report postconcussive syndrome symptoms such as headache, memory difficulties, dizziness, and irritability; however, these same symptoms are very common in general and were as common in those with orthopedic injuries as in those with mTBI in a cohort of university students. However, in a retrospective cohort study of military personnel with mild TBI versus nonhead injury, those with mild TBI (n = 334) were more likely than the nonhead injury (n = 658) group to report several symptoms, including tinnitus (odds ratio [OR] =1.63, 95% confidence interval [CI] = 1.10–2.41) and dizziness (OR = 10.60, 95% CI = 3.48–32.27). In other studies, the link between mTBI and persisting postconcussive syndrome symptoms lasting more than a year is tenuous. An online questionnaire study found postconcussive syndrome symptoms present among controls without mTBI at essentially the same rate as in those without mTBI. Furthermore, the severity of the concussion or duration of loss of consciousness correlates very poorly with persistent postconcussive syndrome symptoms. Interestingly, one study of 176 mTBI patients found that postconcussive syndrome was actually more prevalent in those without abnormalities on cerebral imaging, whereas those with imaging abnormalities were more likely to have auditory or vestibular abnormalities.
Even so, some studies have suggested some connection between postconcussive syndrome symptoms and microstructural brain changes in mTBI patients. Using an MRI technique to measure impaired structural integrity due to diffuse axonal injury, patients with mild traumatic brain injury with postconcussive syndrome showed more severe and persistent structural integrity changes than did those mTBI patients without postconcussive syndrome symptoms. Furthermore, the severity of postconcussive syndrome symptoms after mTBI also correlates with the degree of microstructural brain injury using similar tract-based spatial statistics on MR diffusion tensor imaging (DTI).
Postconcussion Syndrome versus mTBI
Postconcussion syndrome includes persistence of at least three of the following symptoms after a concussion: headache, dizziness, irritability, reduced concentration, fatigue, insomnia, and photophobia and phonophobia. The term postconcussion dizziness implies it is a component of postconcussion syndrome, an entity with a long history. However, in a patient with a history of minor head trauma, it may be unclear whether the individual has dizziness due to microstructural abnormalities from trauma due to the postconcussive syndrome—without any actual injury to the brain—or whether there is actually an unrecognized labyrinthine cause. Indeed, the possibilities are not mutually exclusive; some patients with postconcussive dizziness may also have a labyrinthine cause, thus posing a particular challenge to clinicians. The diagnosis of posttraumatic dizziness is sometimes used to lump all entities together by simply indicating that the patient reports dizziness after a minor head injury.
Patients with mTBI often report postconcussive syndrome symptoms such as headache, memory difficulties, dizziness, and irritability; however, these same symptoms are very common in general and were as common in those with orthopedic injuries as in those with mTBI in a cohort of university students. However, in a retrospective cohort study of military personnel with mild TBI versus nonhead injury, those with mild TBI (n = 334) were more likely than the nonhead injury (n = 658) group to report several symptoms, including tinnitus (odds ratio [OR] =1.63, 95% confidence interval [CI] = 1.10–2.41) and dizziness (OR = 10.60, 95% CI = 3.48–32.27). In other studies, the link between mTBI and persisting postconcussive syndrome symptoms lasting more than a year is tenuous. An online questionnaire study found postconcussive syndrome symptoms present among controls without mTBI at essentially the same rate as in those without mTBI. Furthermore, the severity of the concussion or duration of loss of consciousness correlates very poorly with persistent postconcussive syndrome symptoms. Interestingly, one study of 176 mTBI patients found that postconcussive syndrome was actually more prevalent in those without abnormalities on cerebral imaging, whereas those with imaging abnormalities were more likely to have auditory or vestibular abnormalities.
Even so, some studies have suggested some connection between postconcussive syndrome symptoms and microstructural brain changes in mTBI patients. Using an MRI technique to measure impaired structural integrity due to diffuse axonal injury, patients with mild traumatic brain injury with postconcussive syndrome showed more severe and persistent structural integrity changes than did those mTBI patients without postconcussive syndrome symptoms. Furthermore, the severity of postconcussive syndrome symptoms after mTBI also correlates with the degree of microstructural brain injury using similar tract-based spatial statistics on MR diffusion tensor imaging (DTI).