Redesign of the Microsurgical Interface with a Novel,Computer-Assisted “Virtual Microscope” System in Laser Phonomicrosurgery

Abstract

Objectives:

(1) Augment surgeon skills through gesture scaling and magnified visualization. (2) Eliminate extensive training using intuitive stylus-based manipulation. (3) Perform active constraints intraoperative planning assisting the surgeon.

Methods:

The virtual microscope elements system are: Motorized Micromanipulator, Graphics Stylus with Tablet, Virtual Microscope (VM), Configuration Interface (CI). The apparatus has been implemented and tested between July and December 2013 by resident surgeons and medical students. The surgeon performs the surgical tasks in the VM interface, consisting of modified head-mount display and HD cameras attached to a microscope. The CI includes different categories: in-surgery messages, choosing assistive features, system configuration, etc. The assistive features in the VM include: Precise aiming and incision with laser, defining virtual scan patterns allowing incision and ablation planning for automatic execution, defining regions where the laser is active (safe area), or inactive (dangerous area). The apparatus was compared with the state-of-the-art Lumenis AcuBlade (AB) interface. Average path outcome measurements following error and statistical subjective evaluations of usability were made.

Results:

The average path following error (root mean square error value) was 0.25 mm while maximum error was 0.66 mm. VM is more accurate and superior to AB, which provided values of 0.51 mm and 1.20 mm, respectively, in earlier trials. The subjective evaluations of usability gave a score of 88.3 for the VM. Earlier trials with AB provided a score of 65.56. VM interface is simple, usable, easy to learn, and appropriate.

Conclusions:

The VM was created to provide improved precision, safety, and better ergonomics for microsurgery procedures. The system provides enhanced 3D visualization and allows delicate maneuvers.