Abstract: A device and method for removing ingrown biological tissue from the fluid passageway of a drainage shunt which has been implanted in a patient to relieve a hydrocephalic condition, includes a tubular catheter which is slidably insertable through the passageway of the drainage shunt. A blade extends from the distal end of the catheter and, as the tubular catheter is rotated, the blade cuts away any biological tissue which has ingrown in the passageway. A viewing element is insertable through the tubular catheter to view the blade's progress through the tubular catheter and determine its relationship with any tissue that has ingrown in the passageway.

Abstract: A trocar has an elongated shaft, and a puncturing head is attached to a distal end of the shaft. The puncturing head can have three blades with sharpened cutting edges. A pathway for light communication is established through three apertures in the puncturing head to a longitudinal bore within the shaft. An endoscope can be positioned in the bore to collect light from the distal end of the shaft. A video monitor is connected to the endoscope for displaying an image of the path of advancement of the trocar.