Lupus is an autoimmune disease where the body’s immune system attacks its own tissues. While it can affect many parts of the body, its involvement with the central nervous system (CNS), which includes the brain and spinal cord, can be complex. When a person with lupus shows signs of neurological or psychological issues, doctors may use advanced imaging to investigate. Magnetic resonance imaging (MRI) offers a detailed look at the brain’s structure and is a common tool in these situations.
Reasons for a Lupus-Related MRI
When lupus affects the central nervous system, the condition is called neuropsychiatric lupus (NPSLE). It can cause a wide range of symptoms, prompting a specialist to order a brain MRI to investigate the underlying cause. A doctor may recommend an MRI if a patient experiences:
- Persistent and severe headaches that do not respond to treatment
- Seizures, which can result from lupus activity in the brain
- Cognitive dysfunction, often called “lupus fog,” involving memory and attention issues
- Psychosis, including hallucinations or delusions
- Stroke-like symptoms that require immediate investigation
Potential MRI Findings in Lupus
An MRI of a lupus patient’s brain can reveal several changes that offer clues about how the disease is affecting the central nervous system. One of the most common findings is the presence of white matter lesions, which appear as bright spots on certain MRI sequences. These are often described as white matter hyperintensities and are found in many patients with NPSLE, appearing in subcortical and periventricular areas of the brain.
The imaging may also show signs of issues with the brain’s blood vessels. This can range from inflammation of the vessel walls, a condition known as vasculitis, to evidence of cerebrovascular disease, which can lead to small strokes. These small infarcts can appear as specific types of lesions on an MRI and are often linked to symptoms like headaches and cognitive dysfunction.
In some instances, an MRI might reveal brain atrophy, which is a generalized shrinkage of brain tissue. This involves both white and gray matter and is identified by the enlargement of the fluid-filled spaces in and around the brain. A less frequent but serious condition that can be identified is Posterior Reversible Encephalopathy Syndrome (PRES), characterized by specific patterns of swelling in the posterior regions of the brain.
The MRI Procedure for Lupus Patients
The process of getting a brain MRI for lupus is the same as a standard brain MRI. There is no special “lupus MRI” machine, but rather a conventional scanner used to find abnormalities associated with the disease. The procedure requires the patient to lie still on a table that slides into a large, tube-shaped magnet, which produces loud knocking and buzzing sounds.
To enhance the detail of the images, a gadolinium-based contrast agent is often injected into a vein. This substance helps highlight areas of active inflammation or breakdown of the blood-brain barrier, making active lupus-related lesions more visible. For example, it can make areas of vasculitis or active demyelination more conspicuous.
The entire procedure lasts from 30 to 60 minutes, depending on the imaging sequences and whether contrast is used. Patients can communicate with the MRI technologist during the scan. The use of gadolinium is considered safe but is avoided in patients with severe kidney problems.
How MRI Results Guide Lupus Care
The findings from a brain MRI are one piece of the puzzle and do not provide a diagnosis on their own. A radiologist interprets the images, and a rheumatologist or neurologist integrates these findings with the patient’s clinical symptoms, physical exam, and lab results. This comprehensive approach is used because many changes seen on an MRI are not exclusive to lupus.
It is important to understand the limitations of the imaging, as a normal MRI scan does not rule out neuropsychiatric lupus. A patient can have significant neurological symptoms even if the brain appears structurally normal. This may be due to circulating antibodies or other factors that do not cause visible changes on a scan.
Some findings, such as non-specific white matter lesions, can be caused by other conditions like high blood pressure or the natural aging process. The MRI results are most powerful when used to support a clinical diagnosis and rule out other potential causes, such as a brain tumor or infection. Evidence of active inflammation, for instance, might prompt a physician to adjust immunosuppressive therapy to better control the disease.