T (1) Relaxation Measurement of Ex-Vivo Breast Cancer Tissues at Ultralow Magnetic Fields

We investigated T (1) relaxations of ex-vivo cancer tissues at low magnetic fields in order to check the possibility of achieving a T (1) contrast higher than those obtained at high fields. The T (1) relaxations of fifteen pairs (normal and cancerous) of breast tissue samples were measured at three magnetic fields, 37, 62, and 122 μT, using our superconducting quantum interference device-based ultralow field nuclear magnetic resonance setup, optimally developed for ex-vivo tissue studies. A signal reconstruction based on Bayesian statistics for noise reduction was exploited to overcome the low signal-to-noise ratio. The ductal and lobular-type tissues did not exhibit meaningful T (1) contrast values between normal and cancerous tissues at the three different fields. On the other hand, an enhanced T (1) contrast was obtained for the mucinous cancer tissue.