Patent Application
20060041291
Ophthalmic surgeons using straight cannula to help introduce instruments into the globe have been limited to date to the use of straight, rigid instruments, or too deformable (“directional”) instruments. Such instruments must first pass through the cannula in an essentially straight configuration. The instrument is then deflected into some angle that is controlled by the surgeon.
The small dimensions associated with devices used in ophthalmic and other microsurgeries can result in higher rates of mechanical failure of instruments during use.
There is a need for a directional probe that has the durability and consistent geometry of a rigid instrument. There is a further need for a directional probe that does not have moving parts which helps to ensure structural integrity of the inserted portion of the instrument. There is yet another need for a directional probe that has a monolithic geometry which is stronger than hardware employing flexible or deformable features and simultaneously provides angulation and cannula compatibility.
The present invention provides solutions for at least some of the issues discussed above. Specifically, some embodiments of the present invention provide an improved apparatus that has the consistent geometry and durability of a rigid instrument. The present invention also provided techniques for manufacturing and sizing the probes and cannulas to be usable with one another. At least some of these and other objectives described herein will be met by embodiments of the present invention.
In one embodiment of the present invention, a directional probe is provided that has the durability and consistent geometry of a rigid instrument. The directional probe may be designed so that it does not have moving parts which helps to ensure structural integrity of the inserted portion of the instrument. In yet another embodiment, a directional probe may have a monolithic geometry which is stronger than hardware employing flexible or deformable features and simultaneously provides angulation and cannula compatibility.
In yet another embodiment of the present invention, a treatment apparatus includes a cannula with a cannula lumen. The cannula has a first average diameter. A probe is positionable in the cannula lumen. The probe has a first section with a second average diameter and a second section with a third average diameter that is less than the second average diameter. At least a portion of the second section has a curved section with at least one radius of curvature. The radius of curvative is selected to provide that as the second section passes through the cannula lumen a first side of the second section is tangential to a first side of the cannula lumen, and a second opposing side of the second section is tangential to a second opposing side of the cannula lumen.
Any of the above embodiments may have features as listed below. For example, the apparatus may have a seal that is created between the cannula and the probe when the probe is positioned in the cannula. The seal may be characterized by the simple close fit of noncompliant materials and surfaces. A major portion of the cannula may have a substantially linear geometry. The cannula may have a tissue penetrating distal end. The probe may have a tissue penetrating distal end. The probe may be rotationally moveable within the cannula when positioned in the cannula. The probe may be moveable in a direction along a longitudinal axis of the cannula when positioned in the cannula. The distal portion of the probe may be configured to provide access to a swept region within a tissue site. In one embodiment, the first diameter may be about 20 gauge to 25 gauge. In another embodiment, the second diameter may be about 20-30 gauge. In yet another embodiment, at least first radius of curvature is 3-30 mm. The probe may have a probe lumen. The probe lumen may be sufficiently sized to receive an optical fiber. The probe lumen may be sufficiently sized to receive an RF electrode. The probe lumen may be sufficiently sized to receive a resistive heating device. The probe lumen may be sufficiently sized to receive an ultrasound device. In one embodiment, the probe is an angled probe with a single outside dimension that is smaller of a diameter of the cannula and a separately provided sleeve that can slip over the outside dimension of the probe and provide a seal with the inside diameter of the cannula. In one embodiment, a clearance S exists between cannula and probe, a length of cannula is 2r, and resultant minimum bend radius of the probe is R, and wherein the bend radius R is based on the following formula: R=(s2+r2)/2s
In another embodiment of the present invention, a method of treatment is provided that includes providing a treatment device a cannula with a cannula lumen, a probe positionable in the cannula lumen, the probe having a first section with a second average diameter and a second section with a third average diameter that is less than the second average diameter, at least a portion of the second section having a curved section with at least one radius of curvature. The method may include introducing a distal section of the cannula into a tissue; introducing the probe through the cannula lumen with a first side of the second section being tangential to a first side of the cannula lumen, and a second opposing side of the second section being tangential to a second opposing side of the cannula lumen; and advancing a distal portion of the probe into a tissue site of the tissue.
With any of the methods herein, the method may further include any of the features or steps disclosed below. For example, the method may include introducing a treatment device through a probe lumen. The treatment device may include an optical fiber, an RF electrode, a resistive heating delivery member, and/or an ultrasound delivery member. The method may include rotating the probe when it is positioned in the cannula lumen. The probe may move in a longitudinal direction relative to an axis of the cannula's lumen. The tissue site may be in an interior of an eye. In one embodiment, the probe may be an angled probe with a single outside dimension that is smaller of a diameter of the cannula and a separately provided sleeve that can slip over the outside dimension of the probe and provide a seal with the inside diameter of the cannula. For any of the above, the probe and cannula may be sized and shaped substantially consistent to that described in
A further understanding of the nature and advantages of the invention will become apparent by reference to the remaining portions of the specification and drawings.
Referring to
A probe 18 is positionable in cannula lumen 14. Probe 18 has a first section 19 with a first average diameter 21, a distal portion 20 with a curved section 22 that has at least one radius of curvature and with a second average diameter 23. In one embodiment second average diameter is the range of about 20-30 gauge. Second average diameter 23 is less than first average diameter.
In one embodiment, directional probe 18 is a rigid instrument that offers the treatment access of an angled device and is simultaneously compatible with an instrument introducing cannula. In one embodiment, directional probe 18 is useful for use by ophthalmic surgeons to help introduce instruments into the globe. Directional probe 10 provides convenience and capability of a standard directional probe in combination with the durability and consistent geometry of a rigid instrument.
Generally, directional probe 10 has few if any moving parts. This ensures structural integrity of the inserted portion of the directional probe 10. Directional probe 10 can have small dimensions and is particularly useful in ophthalmic and other microsurgeries. Directional probe 10 can have a monolithic geometry that is stronger than hardware employing flexible or deformable features to simultaneously achieve angulation and cannula compatibility.
Curved section 22 can have numerous radii of curvature. The curvature of curved section 22 is selected to ensure passage of curved section 22 through the length of cannula 12 without interference. In one embodiment, the curvature of curved section 22 is 3-30 mm. As a nonlimiting example, radii less than 3 mm are only compatible with extremely short cannula which are used often. Such short radii are also not compatible with the minimum bend radius requirements of most multimode optical fibers. As another nonlimiting example, radii greater than 30 mm are sometimes larger than the human eye, precluding their use in invasive ophthalmic surgery. In one embodiment, the curvature of curved section 22 that is selected to provide that as distal portion 20 passes through cannula lumen 14, a first side of distal portion 20 is tangential to a first side of cannula lumen 14, and a second opposing side of the distal portion 20 is tangential to a second opposing side of cannula lumen 14.
In one embodiment, a seal 24 is created between cannula 12 and probe 18 when the probe is positioned in cannula 12. Seal 24 provides a simple close fit of noncompliant materials and surfaces of cannula 12 and probe 18. In one embodiment, a major portion of cannula 12 has a substantially linear geometry.
Cannula 12 may have a tissue penetrating distal end 26. Probe 18 may also have a tissue penetrating distal end 28.
Probe 18 is rotationally moveable within cannula 12 when positioned in the cannula lumen 14. Probe 18 is also moveable in a direction, generally denoted as 30, along a longitudinal axis of cannula 12 when positioned in cannula lumen 14. A distal portion of probe 18 is configured to provide access to a swept region, denoted as 32, within a tissue site.
Referring now to
Referring now to
The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Additionally, U.S. Provisional Application Ser. No. 60/602,166 is fully incorporated herein by reference for all purposes. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. It is intended that the scope of the invention be defined by the following claims and their equivalents.
This application claims the benefit of priority to U.S. Provisional Application Ser. No. 60/602,166 filed Aug. 16, 2004 and is fully incorporated herein by reference for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 60602166 | Aug 2004 | US |
