From the Guidelines
An MRI is not automatically necessary for persistent dizziness three years after a concussion, but it may be warranted if symptoms are worsening, new neurological symptoms develop, or initial treatments are ineffective. The decision to order an MRI should be based on a thorough evaluation of the patient's specific symptoms and medical history. According to the most recent and highest quality study, the positivity rate of head CT in patients presenting with dizziness is very low, approximately 2%, and the diagnostic yield of MRI is also low, around 4%, in the absence of associated neurologic symptoms 1.
Persistent dizziness (or post-concussion syndrome) can have multiple causes, including inner ear problems, cervical spine issues, or rarely, structural brain changes. Less invasive approaches such as vestibular rehabilitation therapy, which specifically addresses balance and dizziness issues, may be recommended first. Medications like meclizine (12.5-25mg every 4-6 hours as needed) may also be considered for symptom management.
The American College of Radiology recommends that brain computed tomography (or MRI) should be used whenever suspicion of a structural lesion exists, such as prolonged disturbance of conscious state, focal neurological deficit, seizure activity, or persistent clinical or cognitive symptoms 1. However, for patients with benign paroxysmal positional vertigo (BPPV), radiographic imaging is not recommended in the absence of additional signs and/or symptoms inconsistent with BPPV that warrant imaging 1.
In the context of post-concussion syndrome, the clinical detection of associated neurologic symptoms is important in triaging patients, and various bedside tests have been developed and validated to assist in triaging patients to one of several defined “dizziness syndromes,” which helps in clinical decision making, including the need for subsequent imaging 1.
Therefore, a thorough clinical evaluation is necessary to determine the need for an MRI in patients with persistent dizziness after a concussion, and the decision should be based on the presence of worsening symptoms, new neurological symptoms, or lack of response to initial treatments.
From the Research
Post-Concussion Dizziness and MRI
- The provided studies do not directly address the need for an MRI for post-concussion dizziness after a concussion 3 years ago 2, 3, 4, 5, 6.
- However, the studies suggest that vestibular rehabilitation therapy (VRT) can be an effective treatment for post-concussion dizziness and imbalance 2, 4, 5.
- The causes of post-concussive dizziness can be divided into non-vestibular, central vestibular, and peripheral vestibular causes, and identifying the underlying cause is crucial for effective management 3.
- Some studies suggest that peripheral vestibular disorders can be identified and treated, while central vestibular disorders may be more challenging to manage 3, 6.
- There is no direct evidence to suggest that an MRI is necessary for diagnosing or treating post-concussion dizziness, but it may be used to rule out other potential causes of dizziness, such as structural abnormalities in the brain or inner ear 3, 6.
Diagnostic Approaches
- A comprehensive diagnostic approach, including a thorough medical history, physical examination, and vestibular testing, is essential for identifying the underlying cause of post-concussive dizziness 3, 4, 5.
- Vestibular testing, such as electronystagmography or videonystagmography, can help identify peripheral vestibular disorders, while imaging studies, such as MRI, may be used to rule out central nervous system abnormalities 3, 6.
- A multidisciplinary approach, involving healthcare professionals from various specialties, including neurology, otolaryngology, and physical therapy, may be necessary for effective management of post-concussive dizziness 2, 4, 5.
Treatment Options
- VRT is a promising treatment option for post-concussive dizziness, with studies showing significant improvements in symptoms and functional outcomes 2, 4, 5.
- Other treatment options, such as medication, cognitive behavioral therapy, and lifestyle modifications, may also be effective in managing post-concussive dizziness, depending on the underlying cause and individual patient needs 3, 6.
- Early intervention and treatment are crucial for optimizing outcomes and reducing the risk of long-term sequelae 2, 4, 5.