The invention relates to a direct reading endoscopic measuring instrument and, more specifically, to a manually operated measuring instrument that is placed in close proximity to an internal anatomical feature and a related method for operation of the measuring instrument. The direct reading endoscopic measuring instrument includes a distal reticule that is passed through an endoscope in a folded position. When extended past the distal end of the endoscope proximate to an anatomical structure to be measured, a remote actuator unfolds the reticule along an axis perpendicular to the endoscope. Graduations on the reticule can be observed to directly measure the size of the anatomical structure.