Tissue retractor apparatus and methods

#The present invention relates to surgical retractor systems, such as brain retractors, and more specifically to devices that may be used to enhance the functionality of such retractors.

#A variety of different devices have been used to retract delicate tissue during surgical procedures. One such device is illustrated in United States Patent Publication Number 2010/0010315 (“Mangiardi”), to which this application claims priority and which is incorporated herein by reference in its entirety. Mangiardi shows two general versions of a retractor for delicate tissue. One version is a closed-channel retractor in the form of a tube (see, e.g., Mangiardi FIG. 3), and the other is an open-channel retractor in the form of a curved channel (see, e.g., Mangiardi FIG. 23).

#FIG. 1 of this application illustrates a soft tissue retractor system such as found in Mangiardi. The retractor system includes a hollow retractor 100, and an introducer 102 that is selectively inserted into the retractor 100. The retractor 100 and/or introducer 102 may include a handle 104 to facilitate manipulation and placement of the retractor system, and a lock to hold the introducer and retractor together. The illustrated handle 104 is molded integrally with the retractor 100, but it may be a separate part. The handle 104 may be configured to connect to a clamp 106, such as the standard surgical clamp 106 shown in FIG. 1. In this example, the handle 104 has a ridge 108 that fits into a corresponding groove 110 on the clamp 106, to prevent relative rotation between the two when engaged. Modifications to this design are described in Mangiardi.

#The following Figures are provided to help explain exemplary embodiments of the invention, but are not intended to limit the claimed invention in any way.

#FIG. 1 is an example of a delicate tissue retractor system that may be used with embodiments of the present invention.

#FIG. 2 is a cutaway side elevation view of an exemplary retractor system navigation module and retractor/introducer system.

#The present disclosure provides exemplary embodiments of various apparatus that can be used with known or future tissue retractor systems. Such features include, for example, guidance systems for monitoring and/or controlling the movement of the retractor system and a clamp that can be used to manipulate the system. The features described herein may be used together or separately, and may be modified as appropriate or desired for the particular application. For illustration, the exemplary embodiments are described herein as they may be adapted for use with a soft tissue retractor such as the one shown in FIG. 1. It will be apparent to persons of ordinary skill in the art, however, that other modifications may be made to embodiments used with devices like the exemplary retractor in FIG. 1, and that other versions may be constructed for use with other devices that are not similar to this exemplary embodiment devices.

#FIGS. 2 and 3 illustrate a first embodiment of a navigation system that may be used with a combined introducer/retractor system. In this embodiment, the introducer/retractor system comprises a hollow retractor 200 into which a hollow introducer 202 is releasably installed. The introducer 202 and retractor 200 may comprise structures as described in Mangiardi, or have other shapes or configurations. In this example, the introducer 202 has a tapered proximal end 204, an approximately straight or slightly tapered center portion 206, and a tapered distal end 208 that extends beyond the retractor 200 and terminates at a tip 210. The tip 210 of the introducer 202 has a tip opening 212 that passes through it. The retractor 200 has a tapered proximal end 214 and a straight or slightly tapered center portion 216, and terminates at the end of the center portion 216 at an opening 218. The outer wall of the retractor 200 may be chamfered or rounded around the perimeter of the opening 218 to help prevent local concentration of pressure when the introducer 202 is removed. The retractor 200 and introducer 202 may be a tube (i.e., a closed channel) having any suitable profile (i.e., shape as viewed along their longitudinal axis 220) that is circular, semicircular, rectilinear, oval, elliptical, or flattened (i.e., provided with one long dimension and one short dimension) to help prevent unnecessary displacement of and pressure on tissue during insertion and use. The retractor 200 and/or introducer 202 also may have an open channel shape (i.e., non-tubular) having a semicircular profile or other profile. For example, the introducer 202 may be tubular with a closed half-circular profile (such as a “D” shape), and the retractor 200 may be an open channel with an open half-circular profile (e.g., a “C” shape) that nests over the introducer profile. The dimensions and shapes of the foregoing features be varied to address different surgical needs. Exemplary dimensions and shapes are provided in the Mangiardi reference. Such devices may be sold in kits that have introducers and retractors of various shapes and/or sizes to provide the surgeon with sufficient variety to address a number of situations.

#The introducer 202 and/or retractor 200 may have transparent walls through which the surgeon can see underlying tissue. For example, the walls may be made of glass, polycarbonate or other transparent or semi-transparent materials. While transparent walls are preferred, it is not required in all embodiments, such as embodiments in which a navigation system supplants the surgeon's reliance on vision to position the introducer 202 and retractor 200. The proximal surfaces of the retractor 200 and introducer (222 and 224, respectively) may be treated to render them non-reflective or glare-resistant, such as by painting them matte black or overmolding a matte layer of material. The walls of the introducer 202 and/or retractor 200 may also be used as a light guide to transmit light to the surgical site at the distal end of the retractor 200, as known in the art and shown, for example, in U.S. Pat. No. 3,417,746, which is incorporated by reference herein.