a medical probe device comprising a catheter having a stylet guide housing with at least one stylet port in a side thereof and stylet guide means for directing a flexible stylet outward through at least one stylet port and through intervening tissue to targeted tissues . the stylet guide housing has an optical viewing means positioned for viewing the stylet and adjacent structure which includes a fiber optic channel means for receiving a fiber optic viewing device . the fiber optic channel means can include a guide port means for directing longitudinal movement of a fiber optic device with respect to the stylet guide means in a viewing zone and a flushing liquid channel in the stylet guide housing having an exit port positioned to direct flushing liquid issuing therefrom across the end of a fiber optic device when positioned in the viewing zone . the optical viewing means can comprise a viewing window positioned in the stylet guide housing for viewing the stylet when it is directed outward from its respective stylet port . the optical viewing means can include a fiber optic channel in the stylet guide housing for receiving the a fiber optic viewing device and aligning the viewing end thereof with the viewing window . windowed devices can include a flushing liquid channel in the stylet guide housing having an exit port positioned to direct flushing liquid issuing therefrom across a surface of the viewing window .