A medical device is provided with a probe including an elongated shaft having a distal end, a proximal end, and an external wall. The probe also includes at least two conductors extending substantially along a longitudinal length of the probe. The probe also includes a strengthening element attached to an outer surface of the external wall of the elongated shaft. The probe is configured to slidably move within a working channel of a delivery device and the strengthening element is configured to limit buckling of the probe as a distal portion of the probe is advanced past a deflection point of the delivery device.
