We propose to develop and evaluate a precise yet low cost electric operative cutting instrument for ophthalmic surgery based on pulsed plasma-mediated dissection of soft tissue in liquid medium. One of the first applications of this device will be in vitreoretinal surgery, namely, for tractionless removal of vitreoretinal membranes. The common techniques for treatment of vitreoretinal membranes are mechanical segmentation, peeling or delamination where a significant degree of traction is often applied to the underlying retinal tissue, and this can induce damage to the internal layers, iatrogenic tears and bleeding. Several attempts to develop laser- based instrumentation for vitreoretinal surgery have been undertaken, but all these systems have failed so far to achieve widespread acceptance due to either extensive collateral tissue damage, or high cost and low efficiency of these systems. One of the most powerful mechanisms of laser-tissue interaction in liquid medium is dielectric breakdown-based plasma generation. This approach, based on application of tightly focused short pulse lasers, has not been accepted clinically in vitreoretinal surgery due to difficulties with tight focusing of the laser beam near the retina in real operational conditions. We propose to use a similar interaction mechanism but without lasers. A sub-microsecond high voltage discharge applied via an intraocular microelectrode will generate plasma in liquid medium and can allow for precise cutting of soft tissue. The energy deposition is confined to the area determined by the size of the electrode - on the order of a few micrometers - thus allowing for very low threshold energy and very fine control of the penetration depth. This system combining high precision, reliability and versatility with low cost will allow for widespread acceptance in operating practice. Applicability of this approach to vitreoretinal surgery and other intraocular procedures, such as capsulotomy and cataract surgery will be tested in-vitro and on animal models including histological analysis, scanning electron microscopy and physiological tests.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
1R01EY012888-01A1
Application #
6260396
Study Section
Special Emphasis Panel (ZRG1-SSS-R (01))
Program Officer
Dudley, Peter A
Project Start
2001-01-01
Project End
2003-12-31
Budget Start
2001-01-01
Budget End
2001-12-31
Support Year
1
Fiscal Year
2001
Total Cost
$292,522
Indirect Cost
Name
Stanford University
Department
Ophthalmology
Type
Schools of Medicine
DUNS #
800771545
City
Stanford
State
CA
Country
United States
Zip Code
94305
Palanker, Daniel; Nomoto, Hiroyuki; Huie, Philip et al. (2010) Anterior capsulotomy with a pulsed-electron avalanche knife. J Cataract Refract Surg 36:127-32
Palanker, Daniel V; Vankov, Alexander; Huie, Philip (2008) Electrosurgery with cellular precision. IEEE Trans Biomed Eng 55:838-41
Palanker, Daniel; Vankov, Alexander; Freyvert, Yev et al. (2008) Pulsed electrical stimulation for control of vasculature: temporary vasoconstriction and permanent thrombosis. Bioelectromagnetics 29:100-7
Butterwick, A; Vankov, A; Huie, P et al. (2007) Tissue damage by pulsed electrical stimulation. IEEE Trans Biomed Eng 54:2261-7
Miller, Jason M; Palanker, Daniel V; Vankov, Alexander et al. (2003) Precision and safety of the pulsed electron avalanche knife in vitreoretinal surgery. Arch Ophthalmol 121:871-7
Palanker, Daniel V; Marmor, Michael F; Branco, Andre et al. (2002) Effects of the pulsed electron avalanche knife on retinal tissue. Arch Ophthalmol 120:636-40
Palanker, D V; Miller, J M; Marmor, M F et al. (2001) Pulsed electron avalanche knife (PEAK) for intraocular surgery. Invest Ophthalmol Vis Sci 42:2673-8