A novel device for hands-free positioning and adjustment of the surgical microscope.

The authors have developed a novel device, which they have named Mari, that allows hands-free utilization of the surgical microscope. The device is attached to the eyepieces of a multifunction counterweight-balanced surgical microscope and consists of a metallic holder with supportive plates that facilitate interaction between the device and surgeon's head. On the holder are installed 1) an electric switch, which allows the surgeon to release the microscope's magnetic clutches, allowing movement of the microscope along the x, y, and z axes as well as the rotational and diagonal ones, and 2) a joystick at the level of the surgeon's mouth for adjustment of focus and zoom. The authors report on the initial experience with the use of the device at the Burdenko Neurosurgery Institute, where the senior author used it in approximately 600 procedures between 2006 and 2012. The surgeries ranged in difficulty and in duration (from 20 minutes to 7 hours, median 2.5 hours). Use of the Mari device resulted in increased accuracy of the surgical manipulations and a reduction in the duration of surgery.