FR2918263A1 - HAND PIECE FOR OPTICAL FIBER OR CANNULA / FIBER OPTIC ASSEMBLY - Google Patents

Abstract

The handpiece comprises a body (1), which is adapted to be threaded on an optical fiber or a cannula / optical fiber assembly and which comprises a handle (10) and a mandrel (11) with at least three jaws (110). ) flexible relative to the base (107) of the handle (10), and a clamping tip (2). Said clamping tip (2) comprises an internal cavity (20) with a conical angle profile at the apex (beta) in a clamping portion, is adaptable to the body (1), and allows depending on the position of the portion clamping relative to the body (1) to adjust the clamping of the jaws (110) of the mandrel (11). The jaws (110) of the mandrel (11) comprise a first part with a cylindrical or conical outer profile extending by a second part with a conical outer profile whose angle (alpha) at the vertex is greater than the angle (beta) of the clamping piece (2). Each jaw (110) of the mandrel (11) is flexible at least in the transition zone (114) between said first and second portions.

Description

HAND PIECE FOR OPTICAL FIBER OR CANNULA / FIBER OPTIC ASSEMBLY

  The present invention relates to a new handpiece intended to receive an optical fiber or a set of cannula / optical fiber connected to a source of light energy, such as for example a laser source. It finds its application primarily in the medical field of surgery or treatment by light radiation, including laser beam.

  Prior art Handpieces are commonly used in the medical field of surgery or laser treatment to manipulate an optical fiber or a cannula / optical fiber assembly that transmits a laser beam from a laser energy source.

  More particularly, handpieces comprising an optical fiber or an optical canulelber assembly are used in orthopedic, dental, ophthalmic surgery or else aesthetically cutaneous or percutaneous surgery. The laser beam is transmitted from the laser energy source to the area to be treated via the optical fiber held within the handpiece, said handpiece being manipulated by the surgeon. For this purpose, the handpieces used by the surgeons must be handy and practical, ie the optical fiber or the cannula / fiber optic assembly must be sufficiently maintained to prevent it from translating longitudinally relative to each other. at the handpiece. Moreover, the handpieces are sterilizable and / or disposable to prevent any risk of infection. For this reason, and when the handpieces are for single use, it is appropriate to pay particular attention to the simplicity of realization and the manufacturing cost of the handpiece. US Patent 5,951,544 discloses a handpiece comprising a clamping device for attaching the optical fiber to the handpiece or releasing the optical fiber. The clamping device comprises a conical profile element whose purpose is to act as a mandrel when the user manipulates the handle of the handpiece. The tapered mandrel-like element has four jaws for clamping the optical fiber as said conical element advances into a housing. The housing has a conical profile substantially identical to the profile of the four-jaw mandrel; for this reason, the clamping of the optical fiber is not totally effective. Indeed, the advancement of the mandrel in the housing is blocked by the friction of the walls of the mandrel on the walls of the housing and not by the abutment of the jaws of the mandrel on the optical fiber.

  Thus, the optical fiber can translate longitudinally inside the handpiece when pushing or pulling on said optical fiber. In addition, the complexity of the handpiece and the number of parts constituting it are detrimental to its manufacturing cost. US Pat. No. 6,574,401 helps to solve at least one of the aforementioned drawbacks. Indeed, the handpiece described in this document has a simplified design compared to US Patent 5,951,544, which helps to reduce its manufacturing cost. However, a first disadvantage is related to the tightening of the mandrel. Indeed, the clamping of the mandrel on the fiber should not be too strong because the jaws could damage the optical fiber. The risk of damage to the fiber is increased when the jaws of the chuck are metal, which appears to be the case in US 6 574 401, since the handpiece described is sterilizable. In practice, with this type of mandrel, in order to avoid damaging the optical fiber, the jaws of the mandrel are weakly tightened to the detriment of a reliable immobilization of the optical fiber with respect to the handpiece. It is moreover admitted in this document that the optical fiber can slide inside the handpiece once the mandrel is tightened, and it is recommended to use an adhesive to prevent misalignment of the fiber.

  A second disadvantage is related to the centering of the optical fiber in the body of the handpiece. Admittedly, the use of three jaws instead of four jaws compared to the aforementioned document helps improve the centering of the fiber, but only when they are tight. Indeed, the centering of the optical fiber is only done when one begins to tighten the jaws of the mandrel on the optical fiber. However, when the optical fiber is inserted into the body of the handpiece, the jaws of the mandrel being loosened, the end of the fiber can be housed in one of the slots between two jaws of the mandrel, the risk of damaging to break, the heart of the fiber. This risk of damage to the core of the fiber is also increased by the use of metal jaws. To avoid damaging the fiber, it is recommended in this document to use a protective tip temporarily covering the distal end of the optical fiber during insertion into the body of the handpiece. The use of this protective tip nevertheless complicates the assembly of the fiber on the handpiece.

  OBJECT OF THE INVENTION The main object of the present invention is to propose a new handpiece of simple, inexpensive design that makes it possible to very reliably immobilize an optical fiber or a cannula / optical fiber assembly with respect to said handpiece, without damage the core of the optical fiber. SUMMARY OF THE INVENTION The handpiece of the invention has the following known features of US 6,574,401: It comprises a body which is adapted to be threaded onto an optical fiber or a cannula / optical fiber assembly and which comprises a handle and a mandrel with at least three jaws flexible relative to the base of the handle, and a clamping endpiece which comprises an internal cavity with a conical angle profile at the apex (j3) in a clamping portion, said endpiece being adaptable to the body and allowing depending on the position of the clamping portion relative to the body to adjust the clamping jaws chuck. Characteristically according to the invention, the jaws of the mandrel comprise a first part with cylindrical or conical outer profile extending by a second part with conical outer profile whose angle (a) at the top is greater than that of the first part and is less than the vertex angle (3) of the clamping portion of the clamping bit and that each jaw of the mandrel is flexible at least in the transition zone between said first and second parts. but optionally according to the invention, the handpiece has the following additional technical characteristics, taken separately or in combination: the body and the endpiece are made of plastic, the body and the endpiece are made of polypropylene, - the edges of the jaws are rounded, -the endpiece comprises at its distal end a tapping for the adaptation of needles or infusions having a thread, - the inner profile The chuck jaws form a cone angle at the apex cp, and decreasing in the direction of the distal end of the jaws. Another object of the invention is an assembly comprising an optical fiber or a cannulated / optical fiber assembly threaded and immobilized by clamping in a handpiece conforming to that described above.

  More particularly, the optical fiber of the assembly is connected to a source of light energy. More particularly, before clamping the mandrel (11), the optical fiber (3) or the cannula / optical fiber assembly (3) is able to slide in the mandrel (11) of the handpiece, so as to adjust the length (L) of the distal portion of the optical fiber (3) or the cannula / optical fiber assembly (3) exiting the handpiece. Another object of the invention is a method of placing and immobilizing an optical fiber or a cannula / optical fiber assembly within a handpiece as described above. This method comprises a first step of engaging the tip of the handpiece on the body of the handpiece, a second step of inserting the optical fiber or the cannula / fiber optic assembly into the body and in the tip, and a third step of clamping the tip on the handle so as to cause the translational movement of said tip relative to the body and to strongly tighten the mandrel on the optical fiber or on the assembly cannula / fiber optical. More particularly, but not necessarily, when inserted into the mandrel, the optical fiber or the cannula / optical fiber assembly pushes the jaws of the mandrel. Also, during the process, prior to the clamping step, the length (L) of the distal portion of the optical fiber (3) or the cannula / optic fiber assembly (3) exiting the workpiece is adjusted. hand, sliding the optical fiber (3) or the cannula / optical fiber assembly (3) in the mandrel. BRIEF DESCRIPTION OF THE DRAWINGS The invention and its advantages will be better understood on reading the description which follows, given solely by way of nonlimiting and non-exhaustive example, and with reference to the appended figures among which: FIG. 1 is a perspective representation of a handpiece according to the invention assembled on an optical fiber; FIG. 2 is a longitudinal sectional view of the body of the handpiece of FIG. 1 in a first variant embodiment. FIG. 3 is a longitudinal sectional view of the clamping piece of the handpiece of FIG. 1; FIG. 4 is a cross section IV-IV of the body of the handpiece of FIG. 1; Figure 5 is a longitudinal sectional view of the handpiece in a first clamping position of the mouthpiece on the body of the handpiece, Figure 6 is a longitudinal sectional view of the handpiece. in a second position of lock age of the tip on the body of the handpiece, - Figure 7 is a sectional view of the handpiece in a third clamping position of the tip on the body of the handpiece, - the figure 8 is an enlarged representation of FIG. 6 of the clamping zone of the mandrel on the optical fiber. Figure 9 is a longitudinal sectional view of the body of the handpiece in a second embodiment, - Figure 10 is a longitudinal sectional view of the handpiece in a third step of clamping the tip on the With the aid of a body, a needle being mounted on the endpiece Detailed description FIG. 1 shows a handpiece 1, 2 which is in accordance with the invention and which is threaded and fixed onto an optical fiber 3. The fiber Optical 3 is known per se and comprises a core for the guided light propagation delivered by a light source, and a mechanical protection sheath surrounding the core. The mechanical protective sheath is for example plastic. The core of the optical fiber generally comprises a central portion for the propagation of light and a thin intermediate layer, commonly referred to as cladding, and surrounding the central portion, for the confinement of light in the central portion. The heart of the optical fiber is most often stripped at the distal end. In the context of the invention, the optical fiber 3 can also be replaced by a set of cannula / optical fiber, that is to say an assembly comprising a cannula containing an optical fiber 3. The term cannula is taken in its acceptance the most general and covers any medium or hollow guide elongated, curved or rectilinear, allowing the introduction and guiding of the optical fiber. The cannula may for example be made of stainless steel, titanium or any other biocompatible metal.

  The optical fiber 3 is intended to be connected to a source of light energy, such as for example a laser source, a source comprising one or more high-power LEDs, .... The handpiece finds its application mainly in the medical field, and allows the manipulation of the optical fiber 3 or a set of cannula / optical fiber 3, so as to direct the light beam from the optical fiber on a body region to be treated by means of this beam. Depending on the case, the treatment may be of the invasive type (the optical fiber being introduced into the body) or of the non-invasive type. Referring to Figure 1, the handpiece according to the invention comprises a hollow body 1 threadable and serable on an optical fiber 3, and a hollow clamping end 2, adapted to be assembled on said body 1. The body 1 and the clamping end 2 are preferably made of plastic, and more particularly of polypropylene. In this case, the handpiece is intended for single use, and is discarded after use. FIG. 2 shows a sectional view of the body 1 and in FIG. 3 a sectional view of the endpiece 2 of the handpiece. The body 1 comprises a threading 105 capable of cooperating with a tapping 21 of the clamping bit 2 for screwing said clamping tip 2 to said body 1. In addition, the body 1 of the handpiece comprises a sleeve 10 of length LI prolonged by a mandrel 11 of length L2. The handle 10 comprises a funnel-shaped internal cavity 100 designed to guide an optical fiber towards the mandrel 11. The handle 10 comprises on its outer wall 10a, at its proximal end 101, grooves 102 to improve the grip. hand and has 25 at its distal end 104 a thread 105 intended to cooperate with the tapping 21 of the nozzle 2 and opening on a base 107 for the mandrel 11. Finally, the handle 10 comprises an opening 103 at its proximal end 104 and an outlet port 106 at its distal end adapted to pass the optical fiber through the handle 10 and to the mandrel 11. The thread 105 and the orifice 106 located at the distal end 104 of the handle 10 open on the mandrel 11.

  Referring to Figure 4, the mandrel 11 comprises three jaws 110 constituted by tabs separated from each other by slots 111 which are arranged at 120 from each other. Each tongue of the mandrel 11 has a substantially triangular cross-section, whose longitudinal edges 112 are rounded so as not to damage the optical fiber, and more particularly its core, during the clamping of the mandrel. Also, the tongues with jaw function are slightly flexible relative to the base 107 of the handle 10 of the body 1. The jaws 110 comprise a first portion 110a extending through a second portion which, in the illustrated example, extends to the distal end of the jaw. The outer profile of the first portion 110a is cylindrical or conical and the outer profile of the second portion 110b is conical and has a vertex angle α which is greater than the apex angle of the outer profile of the first portion 110b. For the sake of simplification of the definition of the invention, when the outer profile of the first portion 110a is cylindrical, it is considered in the present text that it has a zero apex angle. In the particular example illustrated in FIG. 2, in the absence of mechanical clamping stress, the jaws 110 delimit a substantially cylindrical passage 113, in the continuity of the orifice 106, intended to receive the optical fiber. The diameter of the passage 113 of the nozzle 11 is preferably slightly smaller than the diameter of the orifice 106 of the handle 10. In FIG. 2, reference is made to 114, the transition zone between the first portion 110a and the second portion 110b. (Angle change area for the outer profile of the jaw 110). Each jaw 110 of the mandrel 11 is slightly flexible in this transition zone 114, which advantageously makes it possible to increase the pressure surface on the optical fiber during the clamping of the mandrel 11. In the rest of the description, these transition zones 114 will be designated edges.

  The inner profile of the jaws 110 of the mandrel is also advantageously planar, so that the fiber can not be damaged when inserted into the mandrel. Indeed, the heart of the optical fiber is generally stripped at the distal end and is therefore vulnerable in the event of contact or impact with an external element. Since the internal profile of the jaws 110 of the mandrel is plane, the core of the fiber can not come into contact with the jaws 110 and it is the protective sheath that comes into contact with said jaws 110. The clamping piece 2, shown in FIG. Figure 3 shows a generally hourglass-shaped exterior appearance to facilitate and improve handling of the handpiece by the user. More specifically, the tip comprises on its outer wall 2a a D depression for handling the tip 2 and therefore the handpiece as a pen. Furthermore, like the handle 10, the tip 2 comprises on its outer wall 2a and at the proximal end 22 of the grooves 23 to facilitate and improve grip.

  The internal cavity 20 of the clamping piece 2 in the form of a funnel and comprises a first cylindrical portion 202 in which is formed the tapping 21 for screwing the clamping tip 2 on the body 1, extended by a second frustoconical clamping portion 200 of apex angle [3 and a third cylindrical portion 201. The inner wall 2b of the second portion 200 and the third portion 201 is smooth. Characteristically according to the invention, the apex angle r3 of the frustoconical clamping portion 200 of the nozzle 2 is smaller than the apex angle a of the frustoconical portion 110b of the mandrel 11. In the particular example illustrated in Figures 1 to 8, the apex angle a is 10 and the apex angle 13 is 8. Preferably, the clamping endpiece 2 also comprises a secondary cavity 20 ', which is distinct from the cavity 20, and which is formed at the distal end of the clamping endpiece 2. This cavity 20' has a thread L Luer Lock type for the adaptation of various elements such as needles, perfusions, etc ... Grooves 23 'have also been made at the distal end 24 of the tip 2 to improve grip during the treatment. adaptation of an element to the Luer Lock thread. Finally, the clamping tip 2 comprises at its distal end 24 a tubular portion 25 projecting, having an opening 250 which allows the passage of the optical fiber and whose diameter is greater than that of the optical fiber. The introduction in place of an optical fiber 3 inside the body 1 of the handpiece, and the immobilization of this optical fiber by clamping the jaws 110 of the body 1 on the optical fiber, by means of the clamping tip 2, will now be described. A first step is to briefly engage the thread 105 of the body 1 in the tapping 21 of the nozzle 2 in order to secure these two elements 1, 2. The mandrel 11 and its jaws 110 are then housed inside of the internal cavity 20 and more particularly at the level of the frustoconical portion 200. With reference to FIG. 5, a second step then consists of threading the optical fiber 3 inside the handpiece constituted by the body 1 and the 2. To this end, the optical fiber 3 is threaded into the opening 103 formed at the proximal end 101 of the handle 10 until said fiber 3 emerges through the opening 250 formed in the tube The distal end of the optical fiber 3 thus passes successively through the opening 103, the orifice 106 and the passage 113, and finally the opening 250. Finally, a third step , shown in FIGS. 6 and 7, consists of screwing the plug 2 clamping on the handle 10 so as to cause the displacement in translation of said tip 2 relative to the body 1 and strongly tighten the mandrel 11 on the optical fiber 3. Indeed, during this step, we can observe a bending of tongues constituting the jaws 110 of the mandrel 11 relative to the base 107 of the handle 10. Also, the angle 30 at the apex of the frustoconical portion 110b of the jaws 110 being smaller than the vertex angle R of the frustoconical portion of 200 clamping of the nozzle 2, the contact between the jaws 110 and the inner wall 2b of the nozzle 2 is in the transition zone 114 (edges). Thus, advantageously, there is no friction between the two frustoconical portions 110b and 200 and more the clamping piece 2 is screwed onto the thread 105 of the handle 10, plus the stress exerted on the ridges 114 in the jaw transition zone 110 is important which results in a flexion of the jaws 110 between the first cylindrical portion 110a and the frustoconical portion 11 Ob. This bending causes an increase in the area of contact between the edges 114 of the mandrel 11 and the inner wall 2b of the tip 2. An additional pressure of the end of the jaws 110 is then exerted on the protective sheath G surrounding the optical fiber which makes it possible to create a local deformation on said sheath G. With reference to FIG. 5, the deformation creates a shoulder that effectively and unequivocally blocks the optical fiber in the handpiece so that it can not turn on herself or translate. Furthermore, it is possible to first thread the optical fiber 3 into the body 1, then to thread the tip 2 on the optical fiber portion 3 protruding from the body 1 (Figure 8) and to tighten said tip 2 on said body 1 (Figures 5, 6 and 7). However, this method is much less convenient than that previously described. Also, and advantageously according to the invention, the user can, prior to tightening the clamping tip 2, easily adjust the length (L ') of the distal portion of the optical fiber 3 or the cannula / optical fiber exiting the handpiece (see Figure 5) by sliding in the mandrel 11. In addition, depending on the diameter of the optical fiber, the stroke of the handle 10 in the tip 2 is variable and the position of the ends of the jaws 110 in the inner cavity 20 of the tip 2 therefore depends on the diameter of the optical fiber.

  It should be noted that, in a characteristic manner according to the invention, the handpiece being made entirely of polypropylene and the edges 114 of the jaws 110 being blunt and rounded, the deformation generated by the jaws 110 to create the shoulder is sufficient. to deform the protective sheath but can not damage the core of the optical fiber. Also, when using the handpiece with a cannula / optical fiber assembly where the cannula is a hollow metal insert, the deformation caused by clamping the jaws is less important than that created on a protective plastic sheath but is sufficient to lock the assembly in the mandrel 2. In addition, when used with a metal cannula the frictional force and the adhesion between the polypropylene and the metal is greater than the adhesion between the polypropylene and the plastic constituting the sheath. In a second variant embodiment of the invention shown in FIGS. 9 and 10, at rest, the inner profile of the jaws 110 of the mandrel 11 of the handpiece forms a corner cone at the apex cp, centered on the central axis longitudinal 11a of the mandrel 11, and of decreasing section towards the distal end of the jaws 110. Thus, the distal ends of the jaws 110 are brought together and the diameter of the passage 113 decreases from the base 107 to the distal end of the mandrel 11. This internal geometry of the jaws 110 contributes advantageously to the centering of the optical fiber in the mandrel 11. Indeed, the inclination of the jaws 110 relative to the base 107 reduces the width of the slots 111. Thus, during the insertion of the fiber into the mandrel 11, the latter pushes the jaws 110 away and can not penetrate inside one of the slots 111. It is thus advantageously guided and centered by the jaws 110 up at the opening 250 of the nozzle 2 (Figure 10). In addition, the apex angle cp of the jaws 110 is dimensioned so as not to damage the core of the fiber. More specifically, the core of an optical fiber is substantially stripped at its distal end (the cladding does not cover the heart in this part) so that it is vulnerable to shocks. However, in this second variant, the angle c1) is calculated so that the inner profile of the mandrel 11 can not come into contact with the core of the optical fiber during its insertion into the mandrel 11. The introduction of a optical fiber 3 inside the body 1 of the handpiece according to the second variant, and the immobilization of this optical fiber by clamping the jaws 110 of the body 1 on the optical fiber, by means of the clamping tip 2 are similar to what has been described for the first variant of the body 1. Nevertheless, in the second step, during the insertion of the fiber into the body 1 of the handpiece, the cladding of the optical fiber pushes on the inner wall of the jaws 110, which substantially increases the passage 113, thus contributing to improve the centering of the optical fiber in the body 1 and the tip 2 of the handpiece. Referring to Figure 10, there is shown a handpiece on which has been screwed a needle A comprising a nozzle E Luer Lock type adapted to cooperate with the internal thread L. As explained above, the inner cone formed by the jaws 110 contributes to the proper centering of the optical fiber not only in the mandrel 11 but also to the opening 250 formed in the tip 2. Thus, the optical fiber penetrates perfectly inside the needle A.

  The invention is not limited to the embodiment of the appended figures. Other embodiments within the scope of those skilled in the art and covered by the appended claims may be envisaged, without departing from the scope of the invention. For example, one could also imagine a handpiece whose first part of the mandrel comprises a cylindrical outer profile and a conical inner profile.

Claims (12)

  Handpiece comprising a body (1), which is adapted to be threaded on an optical fiber or on a cannula / optical fiber assembly and which comprises a handle (10) and a mandrel (11) with at least three jaws ( 110) flexible relative to the base (107) of the handle (10), and a clamping bit (2) which comprises an internal cavity (20) conical profile of apex angle ((3) in a portion of clamping (200), said tip (2) being adaptable on the body (1) and allowing depending on the position of the clamping portion (200) relative to the body (1) to adjust the clamping of the jaws (110) of the mandrel (11), characterized in that the jaws (110) of the mandrel (11) comprise a first portion (110a) with a cylindrical or conical outer profile extending through a second portion (110b) with a conical outer profile whose angle ( a) at the top is greater than that of the first part and is less than the apex angle ((3) of the clamping portion (200) of the clamping bit (2), and in that each jaw (110) of the mandrel (11) is flexible at least in the transition zone (114) between said first and second portions.   2. Handpiece according to claim 1, characterized in that the body (1) and the tip (2) are made of plastic.   3. Handpiece according to claim 2, characterized in that the body (1) and the tip (2) are made of polypropylene.   4. Handpiece according to claims 1 to 3, characterized in that the edges (112) of the jaws (110) are rounded. 25   5. Handpiece according to claims 1 to 4, characterized in that the tip (2) comprises at its distal end (24) a thread (L) for the adaptation of needles or infusions having a thread.   6. Handpiece according to any one of claims 1 to 5, characterized in that the inner profile of the jaws (110) of the mandrel 30 (11) forms a cone angle at the apex cp, and of decreasing section in the direction the distal end of the jaws (110).   7. An assembly comprising an optical fiber (3) or a cannula / optical fiber assembly (3) threaded and immobilized by clamping in a handpiece according to any one of claims 1 to 6.   8. The assembly of claim 7, characterized in that before clamping the mandrel (11), the optical fiber (3) or the assembly cannula / optical fiber (3) is slidable in the mandrel (11) of the handpiece, so as to adjust the length (L ') of the distal portion of the optical fiber (3) or the assembly cannula / fiber optic (3) exiting the handpiece.   9. An assembly according to claim 7 or 8, characterized in that the optical fiber (3) is connected to a source of light energy.   10. A method of placing and immobilizing an optical fiber (3) or a cannula / optical fiber assembly (3) inside a handpiece according to one of claims 1 to 6, characterized in that it comprises a first step of engaging the tip (2) of the handpiece on the body (1) of the handpiece, a second step of insertion of the optical fiber ( 3) or of the cannula / optical fiber assembly (3) in the body (1) and in the endpiece (2), and a third step of clamping the endpiece (2) on the handle (10) so as to to cause translational movement of said tip (2) relative to the body (1) and to strongly tighten the mandrel (11) on the optical fiber (3) or on the assembly cannula / optical fiber (3).   11. The method of claim 10, characterized in that during insertion into the mandrel (11), the optical fiber (3) or the assembly cannula / optical fiber (3) pushes the jaws (110) of the mandrel ( 11).   12. The method of claim 10 or 11, characterized in that before the clamping step, the length (L ') of the distal portion of the optical fiber (3) or of the assembly cannula / optical fiber is adjusted. (3) exiting the handpiece, sliding the optical fiber (3) or the cannula / optical fiber assembly (3) in the mandrel.