How are ganglion cysts diagnosed?
Doctors diagnose a ganglion cyst based on what it looks like, whether it feels tender when pressure is applied, and its location. Because a ganglion cyst is filled with fluid, the doctor may also shine a small light, such as a pen light, through it to confirm that it is a ganglion cyst. If a diagnosis is still not certain, the doctor may order an X-ray to rule out more serious medical conditions such as arthritis or a bone tumor, or an ultrasound to confirm that the lump is a cyst.
On other occasions, ganglion cysts are so small that they do not cause the physical swelling that helps a doctor properly diagnose it. These painful cysts, known as occult ganglions, are often hidden and require imaging tests to be discovered and diagnosed. In this case, your doctor may order a magnetic resonance imaging (MRI) test. An MRI uses magnet, radio waves, and a computer to take a series of very clear, detailed pictures of a part of the body, and will reveal the presence of occult ganglions.