Does the angle of the intsruments matter during two handed endoscopic ear surgery?

The micro-ear instruments are designed to work with the operating oto-microscope where the principle of working depends on the magnification and the focal length of the objective lens. The focal length of the microscope allows a greater working distance for manipulation of the instruments. During the endoscopic ear surgery, the length of instrument interferes with the length of the endoscope making the working under the lens difficult. Hence reaching to the corners of the middle ear becomes impossible with the straight micro-ear instruments during endoscopic ear surgery. Hence certain modifications are required in the existing micro ear instruments so as to be used in endoscopic ear surgery.