Brain MRI. This is the most likely — and most reliable — diagnostic imaging scan healthcare providers can use when diagnosing CJD.
Electroencephalogram (EEG). This test can help detect signs of unusual brain activity. While similar activity can happen with other conditions besides CJD, this test can still offer useful clues to healthcare providers as they work on a diagnosis.
Spinal tap (lumbar puncture). This test takes cerebrospinal fluid (CSF), which surrounds your brain and spinal cord, and analyzes it. High levels of certain proteins in your CSF can indicate a condition like CJD, and shaking a CSF sample under certain circumstances can cause changes that indicate a problem related to prions and proteins.
Brain biopsy. This test involves taking a sample of your brain tissue and analyzing it. A brain biopsy is the most definitive way to confirm CJD diagnosis. However, brain biopsies almost always happen after death, so they’re only good for confirming or ruling out a CJD diagnosis.
Genetic testing. Analyzing a sample of your blood or saliva can show if you have a genetic mutation that increases your chance of developing CJD.