Patent Application
20110144562
The present invention relates generally to the field of eye surgery and more particularly to methods and apparatus for localized pharmacological treatment of ocular tissue during eye surgery using high-intensity pulsed electric fields.
Pharmacological treatment of ocular tissue frequently accompanies eye surgery, e.g., to treat retinal disorders, optical nerve disorders, and the like. For example, anti-vascular endothelial growth factor agents, neuroprotectants, antioxidants, corticosteroids, and other pharmacological solutions may be applied during eye surgery to ocular tissue suffering from such disorders.
Pharmacological solutions such as these, however, often do not just affect ocular tissue intended for treatment. Rather, they tend to also affect any adjacent, healthy ocular tissue, since diffusion of the solution and other practicalities complicate precise control of which tissues are treated. As exposure of healthy ocular tissue to these pharmacological solutions may result in unacceptable tissue damage or harmful side effects, reliable approaches for localizing pharmacological treatment of ocular tissue would significantly contribute to the success of eye surgery.
As described more fully below, embodiments of the present invention treat ocular tissue within a localized portion of an eye during eye surgery with a pharmacological solution. To mitigate risk of damage to adjacent, healthy ocular tissue, the present invention delivers the pharmacological solution to only a portion of the eye and then alters the effectiveness of at least some of the solution delivered by applying a high-intensity pulsed electrical field (HIPEF) to that solution, using a HIPEF probe.
More particularly, a high-intensity pulsed electrical field (HIPEF) apparatus includes a HIPEF probe, an irrigation system, and a high voltage generator. The irrigation system delivers a pharmacological solution to ocular tissue within a portion of the eye, via an irrigation channel in the HIPEF probe or a cannula independent from the HIPEF probe. The HIPEF probe then alters the effectiveness of at least some of the solution delivered, by applying a HIPEF generated by the high voltage pulse generator.
In some embodiments, for example, the irrigation system delivers an inactive pharmacological solution that does not substantially affect treatment of ocular tissue, but the HIPEF probe activates the solution by applying the HIPEF. As the HIPEF probe applies the HIPEF with high precision, the HIPEF activates the solution, and thereby renders the solution effective for treating ocular tissue, only within select and localized portions of the eye.
In other embodiments, the irrigation system delivers a pharmacological carrier encapsulating an active pharmacological solution. Although the solution is active, the solution has no effect on treatment of ocular tissue because it is encapsulated within the carrier. The HIPEF probe then penetrates the pharmacological carrier by applying a HIPEF to the carrier, thereby exposing the tissue to the active solution and rendering the solution effective in treating that tissue. The solution is delivered in a way, e.g., with a high concentration and low dose, such that it diffuses only to ocular tissue within a localized portion of the eye and not to adjacent, healthy ocular tissue.
With the above described advantages, the present invention is particularly well suited in the context of treating retinal tissue suffering from various retinal disorders. For example, the present invention may selectively treat retinal tissue within a localized portion of the eye, without significantly affecting adjacent, healthy retinal tissue.
Of course, those skilled in the art will appreciate that the present invention is not limited to the above features, advantages, contexts or examples, and will recognize additional features and advantages upon reading the following detailed description and upon viewing the accompanying drawings.
The present disclosure describes an apparatus and method for treating ocular tissue within a localized portion of an eye during eye surgery with a pharmacological solution. By localizing pharmacological treatment of ocular tissue, the apparatus and method mitigate the risk of damage to adjacent, healthy tissue.
In one embodiment, the apparatus and method treat ocular tissue with a pharmacological solution using a high-intensity pulsed-electrical-filed (HIPEF) apparatus similar to that described by Steven W. Kovalceck in U.S. patent application Ser. No. 11/608,877, filed 11 Dec. 2006 and titled “System For Dissociation and Removal of Proteinaceous Tissue” (hereinafter “the Kovalcheck application”), the entire contents of which are incorporated herein by reference.
The Kovalcheck application describes using a high-intensity pulsed-electrical-field (HIPEF) rather than classical mechanical means historically used to engage, decompose, and remove vitreous tissue. The application of such a rapidly changing electrical field causes a local temporary dissociation of the adhesive and structural relations in components of vitreous tissue, thereby enabling vitreous tissue to be detached from the retinal membrane and removed from the vitreous cavity.
More particularly, the HIPEF is applied to vitreous tissue using a HIPEF probe 110 shown in
To treat ocular tissue for a disorder, e.g., after removing vitreous tissue, the HIPEF apparatus 200 as disclosed herein is further configured to deliver irrigation fluid that consists wholly or partly of a pharmacological solution. In one embodiment, for example, the HIPEF apparatus 200 delivers a pharmacological solution that treats retinal tissue suffering from a specific retinal disorder. However, the pharmacological solution delivered also affects healthy tissue adjacent the tissue intended for treatment. Accordingly, to selectively treat ocular tissue within a localized area, without also affecting adjacent tissue, the HIPEF apparatus 200 delivers the pharmacological solution to ocular tissue only within a portion of the eye 100 and then alters the effectiveness of at least some of the pharmacological solution on treatment of ocular tissue by applying a HIPEF to that solution.
In the embodiment illustrated in
Note that the HIPEF probe 110 primarily enables localized treatment of ocular tissue because of the highly precise and localized HIPEF, not necessarily the highly localized delivery of the pharmacological solution. That is, perfectly localized delivery of the solution to only intended ocular tissue may be substantially unattainable, e.g., even if the solution is delivered in a high concentration and low dose, the solution may nonetheless incidentally diffuse to adjacent, healthy ocular tissue. Notwithstanding this imprecise delivery, the HIPEF probe 110 is configured to apply the HIPEF with high precision, so as to only activate pharmacological solution within select and localized portions of the eye 100 that contain the intended ocular tissue.
Take, for instance, the example in
In the above embodiments, the HIPEF apparatus 200 has been configured to deliver an inactive pharmacological solution to ocular tissue and then alter that solution's effectiveness on treatment of ocular tissue by activating the solution with a HIPEF. Those skilled in the art will appreciate, however, that the present invention is not limited to these embodiments. Indeed, other embodiments are described below with reference to
In
Regardless of whether the HIPEF probe 110 is configured to alter the effectiveness of the pharmacological solution by activating the solution or by penetrating a carrier of the solution, the HIPEF probe 110 generates the pulse shape, the pulse repetition rate, the pulse train length, and other parameters of the HIPEF based on the chemical properties of the solution and/or carrier. The parameters of a HIPEF for altering the effectiveness of a specific pharmacological solution may be, for instance, pre-configured in the HIPEF apparatus 200 for that solution. The parameters of a HIPEF for altering the effectiveness of one or more different pharmacological solutions may also be pre-configured in the HIPEF apparatus 200, whereby a surgeon may select between different pre-configurations based on the pharmacological solution being delivered.
Moreover,
Furthermore, although the approach taught herein has been described above in the context of selectively treating retinal tissue, without affecting adjacent, healthy retinal tissue, those of ordinary skill in the art will understand the applicability of the disclosed invention for selectively treating other ocular tissues. Generally, therefore, the particular ocular tissue to which the disclosed invention is directed does not limit the invention.
Accordingly, those of ordinary skill in the art will readily appreciate that the HIPEF apparatus 200 generally performs the method illustrated in
Of course, this embodiment and all of the other embodiments described above for treating ocular tissue within a localized portion of an eye were given for purposes of illustration and example. Those skilled in the art will appreciate, therefore, that the present invention may be carried out in other ways than those specifically set forth herein without departing from essential characteristics of the invention. The present embodiments are thus to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.
