Purchase this article with an account.
S.R. Sanislo, D. Palanker, A. Vankov, k. Bilbao, M. Marmor, M. Blumenkranz; Bubble-free Plasma Blade for Posterior Segment Surgery . Invest. Ophthalmol. Vis. Sci. 2003;44(13):4877.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: Improved methods are needed for tractionless, precise and rapid dissection of soft ocular tissues in the posterior pole without generation of gas bubbles and with minimal damage to adjacent material. We present a new plasma-mediated cutting technique based upon an extension of the Pulsed Electron Avalanche Knife (PEAKTM) technology, which allows for continuous and nearly bubble-free dissection of membranes and retina. Methods: A microblade of 0.2-0.6 mm in length with insulated flat sides and exposed sharp edges serves as an electrode for PEAK using bi-phasic charge-balanced waveforms with pulse duration varying from 0.1 to 5 us. Retinal dissection has been performed with complete and with partial vitrectomy on excised pig eyes and in-vivo rabbit eyes. Results were analyzed clinically and histologically. Results: When no energy is applied the instrument can be used as a vitreoretinal pick to elevate and expose membranes. A train of charge-balanced pulses of alternating polarity can create uniform cutting along the edge of the blade without generation of visible gas in vitreous and in fluid medium. Smooth cutting without turbulent flow or other mechanical interference occurs when operating at repetition rates around 100 Hz. Histology and propidium iodide staining of live tissue demonstrate that the collateral damage zone extends 40-80 um from the edge. With different waveforms the blade electrode also coagulates. Conclusions: This novel design of a blade electrode and appropriate waveforms further expands the capabilities and scope of applications of PEAK instrumentation. This probe can be used in applications where it is essential to prevent gas formation, such as within vitreous. Such a blade can also be used for capsulotomy and for dissection of other soft ocular tissues.
This PDF is available to Subscribers Only