Patent Description:
When performing surgery, there is often a tradeoff between tissue damage and accessing and visualizing a surgical location. For example, to more fully view tissues in a surgical location, surgeons may need to make larger incisions to create a larger surgical cavity, as well as use surgical retractors for holding open the surgical cavity.

<CIT>) discloses various surgical devices that have integrated means of illuminating a surgical field. Retractors, cannulas, suction devices and the like are disclosed as having integrated optical waveguides that are coupleable to external lighting sources. The optical waveguides feature cladding layers configured to enhance transmission efficiency.

<CIT>) discloses an illumination system that comprises an arthroscope, endoscope or other suitable surgical tool and an attachable cannula comprising a transparent or semi-transparent material capable of carrying light from the proximal end of the cannula to the distal end of the cannula, via a waveguide, thereby illuminating a surgical field. The surgical field is thus illuminated through components that do not occupy space that may otherwise by used for the optics of the arthroscope.

The present disclosure provides a surgical cannula for illuminating a surgical cavity, as set out in accompanying claim <NUM>. Preferred features are set out in the accompanying sub-claim.

Thu, the present invention uses an optically transparent walled passageway and a light source for illuminating the working channel of the walled passageway, such that tissues accessible via the working channel and tissues surrounding the walled passageway are illuminated.

While several features are described herein with respect to embodiments of the invention; features described with respect to a given embodiment also may be employed in connection with other embodiments. The following description and the annexed drawings set forth certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages, and novel features according to aspects of the invention will become apparent from the following detailed description when considered in conjunction with the drawings.

The annexed drawings, which are not necessarily to scale, show various aspects of the invention in which similar reference numerals are used to indicate the same or similar parts in the various views.

The present invention is described below in detail with reference to the drawings. In the drawings, each element with a reference number is similar to other elements with the same reference number independent of any letter designation following the reference number. In the text, a reference number with a specific letter designation following the reference number refers to the specific element with the number and letter designation and a reference number without a specific letter designation refers to all elements with the same reference number independent of any letter designation following the reference number in the drawings.

In a general embodiment, the present disclosure provides a surgical cannula for illuminating a surgical cavity using an optically transparent walled passageway having a working channel. Light from a light source is received by the surgical cannula and is emitted by the walled passageway to illuminate the working channel, such that tissues accessible via the working channel and tissues surrounding the walled passageway are both illuminated.

An exemplary embodiment of the surgical cannula <NUM> (also referred to as a surgical retractor) is shown in <FIG>. In this embodiment, the surgical cannula <NUM> includes a dilator <NUM> having a closed tip <NUM> and a retainer <NUM> having an open tip <NUM>. In this embodiment, the dilator <NUM> pushes soft tissue of the brain out of the way as the retainer <NUM> is advanced into the brain. That is, the dilator <NUM> may be received within an interior working channel of the retainer <NUM>, such that the closed tip <NUM> of the dilator <NUM> extends through and past the open tip <NUM> of the walled passageway <NUM> as shown in <FIG>.

The dilator <NUM> and retainer <NUM> may be releasably attached via a clip <NUM>. For example, the clip <NUM> may attach to a tab <NUM> of the retainer <NUM>. The dilator <NUM> may then be removed while the retainer <NUM> remains in place to retain tissue out of the way and provide a working area for a surgeon. For example, a button <NUM> of the clip <NUM> may be depressed to disengage the clip <NUM> from the tab <NUM> so that the dilator <NUM> may be removed to open the working channel <NUM>.

Turning to <FIG>, an exemplary embodiment is shown of the surgical cannula <NUM> for illuminating a surgical cavity using light <NUM> emitted by a light source <NUM>. The surgical cannula <NUM> includes an optically transparent walled passageway <NUM> having an interior working channel <NUM>, an entrance <NUM>, an open tip <NUM>, an inner surface <NUM>, an outer surface <NUM>, and light-extracting features <NUM>. The walled passageway <NUM> receives the light <NUM> emitted by the light source <NUM> and transports the received light <NUM> via total internal reflection towards the open tip <NUM> of the walled passageway <NUM>. The light-extracting features <NUM> extract the transported light <NUM> from the walled passageway <NUM>, such that the extracted light is emitted from the inner surface <NUM> of the walled passageway <NUM> into the working channel <NUM> and illuminates an area <NUM> bounded by the open tip <NUM> the walled passageway <NUM> (also referred to as a working area).

The light-extracting features may include both inward extracting structures and outward extracting structures. The inward extracting structures extract the transported light, such that the extracted light illuminates the area <NUM> bounded by the open tip <NUM> of the walled passageway <NUM>. The outward extracting structures extract the transported light, such that the extracted light is emitted from the external surface <NUM> of the walled passageway <NUM>. In this way, the outward extracting structures may be used to illuminate the environment (e.g., tissues) surrounding the walled passageway <NUM>.

The light source <NUM> may include multiple light emitters <NUM> configured to emit the light <NUM>. For example, as shown in <FIG>, each of the light emitters <NUM> may be positioned along the entrance <NUM> of the walled passageway <NUM>, such that the light <NUM> emitted by each of the light emitters <NUM> is transported towards the open tip <NUM> of the walled passageway <NUM>.

As described above, the walled passageway <NUM> is optically transparent. That is, the walls <NUM> of the walled passageway <NUM> allow at least a portion of the visible spectrum of light to pass through. For example, the walls <NUM> may be predominantly (e.g., at least <NUM>%) clear. In one example, the walls <NUM> attenuate at most <NUM>%, at most <NUM>%, or at most <NUM>% of the visible spectrum of light. The walled passageway <NUM> may be made of any suitable optically transparent material such as glass and/or plastic. In one embodiment, the walled passageway <NUM> is configured to be sterilized before use.

Each of the light emitters <NUM> may be enclosed within walls <NUM> of the walled passageway <NUM>. For example, the light emitters <NUM> may be positioned within recesses in the walls <NUM> and the light emitters <NUM> may then be encapsulated within the recesses.

In one embodiment, the surgical cannula <NUM> includes a tab <NUM> integrally formed with the walled passageway <NUM>. The tab <NUM> may be optically connected to the walled passageway <NUM> and the light source <NUM>, such that the light <NUM> emitted by the light source <NUM> is received by the tab <NUM> and is transferred by total internal reflection from the tab <NUM> into the walled passageway <NUM>. the tab <NUM> may be any suitable structure mechanically attached to the walled passageway <NUM>. For example, the tab <NUM> may be integrally or monolithically formed without the walled passageway <NUM>.

In the embodiment shown in <FIG>, the surgical cannula <NUM> includes the light source <NUM> and the light source is mechanically supported by the tab <NUM>, such that the light emitted <NUM> by the light source <NUM> is received by the tab <NUM>. The light <NUM> received by the tab <NUM> may be transmitted from the tab <NUM> to the walls <NUM> of the walled passageway <NUM> and then within the walls towards the tip <NUM> of the walled passageway <NUM>.

In the embodiment shown in <FIG>, the light source <NUM> is not supported by the tab <NUM>, but instead the light source <NUM> is optically connected to the tab <NUM> via a light guide <NUM> configured to transfer the light emitted by the light source to the tab <NUM>. For example, the light source <NUM> may be an external light source optically connected to the tab <NUM> via an optical fiber.

In the embodiments shown in <FIG>, <FIG>, the walled passageway <NUM> acts as a light guide for transporting the received light <NUM> from the light source towards the open tip <NUM>. The light-extracting features extract the light being transmitted by the walls <NUM>, such that the extracted light illuminates the area <NUM> bounded by the open tip <NUM> and/or tissues adjacent the outer surface <NUM> of the walled passageway <NUM> as described above.

The light extracting properties of the light-extracting features may vary along the walled passageway <NUM>, such that illumination inside and outside of the working channel <NUM> appears uniform. For example, illumination of the area <NUM> bounded by the open tip <NUM> may vary in brightness by less than <NUM>%, less than <NUM>%, or less than <NUM>%. Similarly, the illumination of the environment adjacent the outer wall <NUM> may vary in brightness by less than <NUM>%, less than <NUM>%, or less than <NUM>%.

The light-extracting features may be configured to extract at least <NUM>% of the light received by the walled passage <NUM>, such that at most <NUM>% of the received light is emitted from the open tip <NUM> of the walled passage <NUM>. That is, the light-extracting features are configured to extract most of the light from the walled passageway <NUM> before the light reaches the open tip <NUM>.

The light-extracting features may be used to control the uniformly of illumination provided by the surgical cannula <NUM>. The light-extracting features may be any suitable structure for extracting light from a structure (such as a light guide) (e.g., to target a specific light output distribution). For example, the light-extracting features may include at least one of surface aberrations, micro-lenses, reflective spots, partial reflective planes, or diffraction gratings. Alternatively or additionally, a diffuser sheet or a <NUM>-D lensing sheet may be (<NUM>) placed on an emission surface. In one embodiment, the surface aberrations include at least one of a contour of the surface, surface depositions, or surface etchings.

As shown in <FIG>, the surgical cannula <NUM> may include a blocking agent <NUM> configured to optically attenuate light. For example, the open tip <NUM> may include the blocking agent <NUM>, such that light emitted from the open tip <NUM> of the walled passageway <NUM> is reduced. Similarly, the entrance <NUM> may include the blocking agent <NUM>, such that light emitted from the entrance <NUM> of the walled passageway <NUM> is reduced.

The blocking agent <NUM> may be any suitable material for attenuating light. For example, as shown in <FIG>, the blocking agent <NUM> may be material added to the walled passageway (such as dark plastic). As another example, the blocking agent <NUM> may be coloring added or applied to the walled passageway (such as dark paint or dye).

In one embodiment, the surgical cannula <NUM> also includes a power source <NUM> electrically connected to the light source <NUM>. In addition to supporting the light source <NUM>, the tab <NUM> and/or walled passageway <NUM> may also mechanically support the power source <NUM>. The power source <NUM> may be any suitable source of electrical energy (e.g., a battery) for supplying electrical power to the light source <NUM>.

In the embodiment shown in <FIG>, the surgical cannula <NUM> includes a light guide <NUM> and an illuminator <NUM>. The light guide <NUM> is configured to receive the light <NUM> emitted by the light source <NUM> and to transmit the received light via total internal reflection to the illuminator <NUM>. The illuminator <NUM> is configured to receive the light transmitted by the light guide <NUM> and to emit the light, such that the light is emitted from the inner surface <NUM> of the walled passageway <NUM> into the working channel <NUM> and illuminates the area <NUM> bounded by the open tip <NUM> the walled passageway <NUM>.

In one embodiment, the illuminator <NUM> is positioned on one side of the walled passageway <NUM>. The illuminator <NUM> may include light-extracting features for emitting light towards and away from the working channel <NUM>. The light directed away from the working channel <NUM> may illuminate tissues outside of and on the same side of the walled passageway as the illuminator <NUM> (i.e., so that these tissues are visible to a surgeon looking through the walled passageway <NUM>). The light directed towards the working channel <NUM> may be used to illuminate the area <NUM> bound by the open tip <NUM>. Additionally, the light directed towards the working channel <NUM> may pass through both the working channel <NUM> and an opposite portion <NUM> of the walled passageway <NUM> located opposite the illuminator <NUM>. In this way, any tissues located on an opposite side of the walled passageway <NUM> are also illuminated.

Embodiments of the surgical cannula <NUM> including the illuminator <NUM> may not include light-extracting features in the walled passageway <NUM>. Instead, the light-extracting features may be present in the illuminator <NUM>. Although, in some embodiments the surgical cannula <NUM> includes light-extracting features in both the illuminator <NUM> and the walled passageway <NUM>.

As shown in <FIG>, the illuminator <NUM> may be encapsulated within the walls <NUM> of the walled passageway <NUM>, such that the illuminator is segregated from an external environment <NUM>. For example, the illuminator <NUM> may be inserted into a channel in the wall <NUM> of the walled passageway <NUM>. In the embodiment shown in <FIG>, the illuminator <NUM> is attached to the outer surface <NUM> of the walled passageway <NUM>. For example, the illuminator <NUM> may be adhered to the outer surface <NUM>. In one embodiment, a coating may also be applied to the illuminator <NUM>, such that the illuminator <NUM> is separated from and does not come in contact with the external environment <NUM>.

As shown in <FIG>, and <FIG>, the illuminator <NUM> may be a linear light guide including light-extracting features configured to extract light from the linear light guide. For example, the illuminator <NUM> may be a fiber optic (e.g., monofilament fiber optic). Alternatively, as shown in <FIG>, the illuminator <NUM> may be a planar light guide including light-extracting features configured to extract light from the planar light guide.

In one embodiment, the light source <NUM> may be attached to a clip for attaching to the tab <NUM>. The clip may be used to maintain a position of the light source <NUM> relative to the tab <NUM> and/or a light guide <NUM>. In another embodiment, the light guide <NUM> is attached to a clip that is used to optically connect an external light source to the tab <NUM>. For example, the clip may have a circular or semicircular shape that attaches to the entrance <NUM> of the walled passageway <NUM>.

The light source <NUM> (and light emitters <NUM>) may be any suitable structure for emitting electromagnetic radiation. For example, the light source <NUM> may include one or more light emitting diodes (LEDs), organic LEDs (OLEDs), micro-LEDs, laser diodes, mini-LED, quantum dot (QD)-conversion, phosphor conversion, excimer lamps, multi-photon combination, or SLM wavefront manipulation.

The light <NUM> may include any suitable wavelengths of light. In addition to supplying light to improve visibility of a surgical cavity, the light source <NUM> may also include light having wavelengths useful for disinfecting the surgical cavity or for performing photobiomodulation. For example, the light <NUM> may include wavelengths (e.g., <NUM>-<NUM>) configured to stimulate wound healing. As an example, the light source <NUM> may include multiple light emitters. One or more of the light emitters may emit the white light for visibility while other light emitter(s) emit photobiomodulation light.

In one embodiment, the surgical cannula <NUM> is used to illuminate a cranial surgical cavity or central nervous system surgical procedure. The surgical cannula <NUM> may be single use or sterilizable (i.e., multi-use).

All ranges and ratio limits disclosed in the specification and claims may be combined in any manner. Unless specifically stated otherwise, references to "a," "an," and/or "the" may include one or more than one, and that reference to an item in the singular may also include the item in the plural.

Claim 1:
A surgical cannula (<NUM>) for illuminating a surgical cavity using light (<NUM>) emitted by a light source (<NUM>), the surgical cannula (<NUM>) comprising:
an optically transparent walled passageway (<NUM>) having an interior working channel (<NUM>), an entrance (<NUM>), an open tip (<NUM>), an inner surface (<NUM>), an outer surface (<NUM>), and light-extracting features;
whereby the light source (<NUM>) comprises multiple light emitters (<NUM>) configured to emit the light (<NUM>), wherein each of the light emitters (<NUM>) is positioned along the entrance of the walled passageway (<NUM>), such that the light emitted by each of the light emitters (<NUM>) is transported via total internal reflection towards the open tip (<NUM>) of the walled passageway (<NUM>); and
wherein the light-extracting features are configured to extract the transported light from the walled passageway (<NUM>), such that the extracted light is emitted from the inner surface (<NUM>) of the walled passageway (<NUM>) into the working channel (<NUM>) and illuminates an area (<NUM>) bounded by the open tip (<NUM>) of the walled passageway (<NUM>).