A medical interventional tool has distal and proximal ends. A responsive material is located at the distal end or elsewhere along the interventional tool and is capable of providing a temperature-dependent or pressure-dependent optical response. At least one optical guide is in optical communication with the responsive material to collect an optical signal from the responsive material located at the distal end or other location along the interventional tool. The at least one optical guide further guides the collected optical signal to an optical output at the proximal end of the interventional tool. An optical response analyzer is configured to receive the collected optical signal from the optical output and to process the collected optical signal to derive therefrom a temperature or pressure reading or indication representative of a temperature or pressure at the distal end or other location along the interventional tool.