What other types of imaging might be used?

Aside from x-rays, CT, MRI, ultrasound, PET, and SPECT, there are other medical imaging modalities that are sometimes used for certain diseases. Some of these techniques are relatively new. The imaging modalities presented here are for informational purposes only. Many of these modalities are still active areas of research and may not have enough evidence to support clinical use in their current forms.

Thermal imaging is a noninvasive imaging technique for detecting and monitoring certain diseases by showing unusual temperatures in a person’s body.

Magnetoencephalography (MEG) examines brain activity by measuring tiny magnetic fields on a person’s scalp. These fields are created by electrical activity from neurons. MEG can be used for finding pathological activity in the brain for people living with epilepsy. It can also be helpful planning for surgery for people with brain tumors.

Optical imaging refers to several techniques that use visible light to look inside a patient, including diffusive optical tomography (DOT), near infrared optical tomography (NIROT), and fluorescence diffuse optical tomography (FDOT). Scientists working in optical imaging use light that is transmitted and scattered by the human body. By measuring this light, they can learn information about a person including blood flow, blood oxygenation, and tumor protein expression.

Thermoacoustic imaging detects acoustic waves from inside a patient after the patient is exposed to a source of energy. As tissue absorbs energy and rises in temperature, it will expand and generate acoustic waves. The thermoacoustic signal reflects the local tissue’s energy absorption property as well as the thermal expansion property.