An example illuminated microsurgical instrument comprises a handpiece, a tubular member connected to the handpiece to perform a medical procedure at an interventional site, a sheath member surrounding a portion of the tubular member and extending toward the distal tip of the tubular member, and an optical fiber positioned within the sheath member and connected to the sheath member, wherein a distal tip of the optical fiber is recessed within the sheath member and directed toward the distal tip of the tubular member. The sheath member and distal tip of the optical fiber may be movable between a proximal position at a first distance from the distal tip of the tubular member and a distal position at a second distance from the distal tip of the tubular member, wherein the second distance is shorter than the first distance. Movement of the sheath member moves the distal tip of the optical fiber to generate a wider illumination or a narrower illumination on the site being visualized.