Cannula with Anti-extrusion system

Abstract

The invention relates to a cannula with an anti-extrusion system, comprising a cannula (1) with a hollow hourglass-shaped internal sliding system (2) having a conical part at both ends and which is longer than the cannula (1) and has a maximum diameter larger than the internal diameter of the cannula (1), the internal sliding system (2) having elastic walls.

Description

[0001] DESCRIPTION

[0002] Cannula with anti-extrusion system

[0003] OBJECT OF THE INVENTION

[0004] The invention, as the title of this specification indicates, is a cannula comprising a retractable anti-extrusion system. It is an innovation that, within current techniques, offers advantages previously unknown.

[0005] The present invention has its field of application within medicine.

[0006] STATE OF THE ART

[0007] In procedures such as vitreoretinal surgery, microcannulas are used, inserted with a trocar. This trocar punctures the tissue and, upon retraction, leaves the microcannula in position. However, sometimes the microcannulas come out of the eye, a phenomenon known as extrusion. This extrusion can occur due to the movements during the operation itself or friction with the surgical instruments. Larger cannulas are also used in laparoscopy and arthroscopy, but these too can become extruded. In these cases, it is necessary to reimplant the cannula, causing discomfort to the patient.

[0008] It is therefore necessary to develop a new type of cannula that cannot be extruded.

[0009] Currently, there is no known device that has structural and constitutive technical characteristics equal to or similar to those described and claimed in this descriptive report.

[0010] DESCRIPTION OF THE INVENTION

[0011] The present invention relates to a cannula that provides a notable innovation within its field of application, the characterizing details that make this possible being conveniently set out in the final claims accompanying this description.

[0012] This cannula can be used, via a trocar, in vitrectomy surgery, laparoscopy or arthroscopy with cannulas, and it prevents the cannulas from coming out of position.

[0013] 2 This system could be effective in treating cystic conditions in dermatology, but it can also be used in other surgical techniques. It allows for the creation of an epithelial or fistulous tract that connects the cyst to the outside, a process known as "marsupialization," thus avoiding the need for complete excision. The microcannula would remain in place for 7-14 days, creating the epithelial tract. This tract, similar to ear piercings, will not close, allowing the cyst to drain continuously on its own without requiring any further intervention.

[0014] The cannula with an anti-extrusion system consists of a cannula with an internal sliding mechanism shaped like a diabolo and, in use, two protruding conical ends, preferably one of the two (the one that remains outside the patient in use, with a high taper or with a more extreme, ruffled end section). The internal sliding mechanism is longer than the cannula and has a maximum diameter greater than the cannula's inner diameter. Furthermore, being an internal sliding mechanism, it has elastic walls.

[0015] Other ways of carrying out the invention are shown below.

[0016] EXPLANATION OF THE FIGURES

[0017] To complete the description being made and in order to help in the better understanding of the characteristics of the invention, a section of drawings is presented where, for illustrative and non-limiting purposes, the following have been represented.

[0018] Figure 1 corresponds to a schematic view of an example embodiment, at the tip of the trocar.

[0019] Figure 2 shows a detail of the previous example, where the retainer has been removed.

[0020] Figure 3 corresponds to a schematic section of an example of a cannula with the sliding system, inserted into the skin of a patient.

[0021] PREFERRED EMBODIMENT OF THE INVENTION

[0022] The embodiment shown in Figure 1 comprises a cannula (1) with a stop (11) to prevent its complete insertion into the patient's body. The cannula (1) also has an internal sliding system (2) in the general shape of a hollow diabolo, with a conical portion protruding externally, i.e., shaped like two truncated cones joined at their smaller bases. The internal sliding system (2) has an inner side, which, when in use, remains inside the patient's skin (5) or body, and an outer side that protrudes. The internal sliding system (2) is longer than the cannula (1), so that once inserted into the patient's body, it protrudes at both ends. However, when in the trocar, ready for puncture, the inner end is retracted inside the cannula (1) for protection (Figure 2).Furthermore, its maximum diameter at the ends of the internal sliding system (2) is greater than the inner diameter of the cannula body (1), while the part inside the cannula (1) is slightly smaller. The outer side or part of the internal sliding system (2) has a larger opening than the inner side, or is finished with a ring or washer, or even with reverse taper (oriented towards the other side) to be able to embrace the cannula stop (11), as shown in the figures.

[0023] The internal sliding system (2) has elastic walls, especially on its inner side, so that it is retained against the patient and the inside of the cannula (1) by the elasticity of its deformation. For example, it may be made of flexible medical-grade plastic, such as polyvinyl or Teflon. The cannula (1) is usually metallic.

[0024] The cannula (1), as shown in the figures, is inserted into the trocar (3), with the advancement of the internal slide blocked by a removable retainer (4) that secures the outer side of the internal slide system (2) (Figures 1 and 2). This retainer (4) allows the physician to puncture the patient's skin without any movement of the cannula (1) or the internal slide system (2). The trocar (3) passes through the cannula (1) snugly, so that they penetrate the skin simultaneously. Once the cannula (1) is inserted, the retainer (4) is removed, and the internal slide system (2) is pushed open by its elasticity within the patient's body, without the cannula (1) being pushed. When the movement is complete, the lower end of the internal slide system (2) protrudes in a conical shape from the inside of the cannula (1) (Figure 3). Thus, the internal sliding system (2) grips the patient's body from the inside.The outer part of the slide clamps against the stop (11) of the cannula (1) (Figure 4) to prevent the inner slide (2) from displacing inside the cannula (1) during surgical maneuvers. To remove the cannula (1), the outer part of the inner slide (2) must be disconnected from the cannula stop (1) and retracted, after first removing the inner slide (2) from the cannula (1). In this way, the cannula (1) is secured by the inner slide (2), creating a continuous flow and preventing extrusion of the cannula (1). Intrusion of the inner slide also does not occur, as it is stopped by the outer part of the inner slide (2), which is fixed to the flat stop (11) of the cannula (1) (which, in turn, prevents intrusion of the cannula (1) itself). Thus, it is possible to empty the cysts (6) by means of the cannula (1) of the invention, since the epithelial tract is maintained.

[0025] To remove the cannula (1), the surgeon detaches the outer part of the internal sliding system (2) from the stop (11) of the cannula (1), gently pulling the internal sliding system (2) out and removing the cannula (1). In larger cannulas (1), the internal sliding system (2) may be thicker and more rigid, increasing friction with the cannula (1), and may not need to fully engage the stop (11). In other words, the double cone of the internal sliding system (2) may be sufficient to retain the cannula (1).

[0026] 5

Claims

CLAIMS 1- Cannula with anti-extrusion system, characterized in that it comprises a cannula (1) with an internal sliding system (2) in the form of a hollow diabolo, with a conical part at both ends, longer than the cannula (1) and with a maximum diameter greater than the inner diameter of the cannula (1), the internal sliding system (2) being elastic walls. 2- Cannula with anti-extrusion system, characterized in that the inner side of the internal sliding system (2), configured to remain in the patient's body, has a smaller opening than the outer side of the internal sliding system (2). 3- Cannula with anti-extrusion system, according to claim 1, characterized in that the internal sliding system (2) is made of medical grade elastic plastic.

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