JP2011206208A - Hot balloon catheter, treatment device, and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain an expansion operation without giving unnecessary heat damage to a living body while heating a target site of a body cavity.SOLUTION: A hot balloon catheter has an optical fiber for introducing a laser light for heating, a photoirradiation part having a side irradiation part for reflecting the laser light vertically with respect to the axial direction of the optical fiber at the tip of the optical fiber, and a double-structured balloon. The double-structured balloon has a first balloon, and a second balloon mounted for containing the first balloon inside. Furthermore, the hot balloon catheter has: a first lumen for communicating to the inside of the first balloon and pouring a first fluid body; a second lumen communicating to a space, which is formed with the outer surface of the first balloon and the inner surface of the second balloon, at the proximal end of the catheter and pouring a second fluid body; and a third lumen communicating to the space at the distal end of the catheter in the space for collecting the second fluid body poured from the second lumen.

Description

  The present invention relates to a hot balloon catheter for expanding a stenosis of a body cavity, a treatment apparatus using the hot balloon catheter, and a control method thereof.

  For example, a hot balloon catheter is used for so-called vasodilatation for expanding a stenosis occurring in a body cavity such as a blood vessel, in particular, a stenosis due to cardiovascular arteriosclerosis. In general, a hot balloon catheter used for vasodilation, etc., which has a balloon that can be inflated and deflated at the tip, and an electrode for high-frequency energization integrated in the inner tube (RF balloon) is proposed. Has been. A laser balloon has also been proposed in which a living body is irradiated with laser light instead of high-frequency dielectric heating to perform heating.

  In the treatment of a vascular stenosis using a hot balloon catheter as described above, an expansion treatment is performed while heating the stenosis at an appropriate temperature by high-frequency dielectric heating (or heating by irradiation with laser light). In such heating and expansion, the elastic fibers of the vascular media are stretched well, and the balloon is pressurized and inflated to mechanically crush the blood vessels and atheroma while plasticizing the thrombus and other lipids. The blood vessel wall is extended to expand the stenosis and improve blood flow. In this way, by expanding the balloon under pressure while heating the stenosis, it is possible to expand the stenosis at a lower pressure than vascular dilation (PCI) performed without heating.

Japanese Patent Laid-Open No. 9-056825

  However, in the RF balloon, in order to ensure safety to the living body, the high-frequency output is suppressed low, and it takes time until sufficient heating for expanding the lumen of the living body is obtained. In addition, it is difficult to limit the heated portion in high-frequency heating, and heating is performed over a wide range, which may cause thermal damage over a wide range. Moreover, since cooling is simply performed by stopping heating (stopping high-frequency output), it also takes time for cooling, lengthening the time required for the expansion treatment, and burdening the patient.

  Moreover, in a laser balloon, a heating site | part can be controlled with the irradiation position of a laser beam. However, when a heated part of a living body is irradiated with laser light and heated, the laser light penetrates into the inside of the living body, and the heated part reaches outside the blood vessel, causing heat damage to normal tissue. There is a possibility that. In addition, since the irradiation position of the laser beam is spot-heated, it takes time to heat the necessary range. Furthermore, as with the RF balloon, since cooling is simply performed by stopping heating (laser light irradiation is stopped), cooling takes time, and the time required for the expansion treatment becomes longer, which imposes a burden on the patient. End up.

  The present invention has been made in view of the above problems, and a hot balloon catheter capable of realizing dilatation while heating a necessary part of a body cavity without causing unnecessary thermal damage to a living body, and a It is an object of the present invention to provide a used treatment apparatus and a control method thereof.

In order to achieve the above object, a hot balloon catheter according to one aspect of the present invention comprises the following arrangement. That is,
A hot balloon catheter for dilating while warming a body cavity,
A light irradiator having an optical fiber for guiding laser light for heating; and a side irradiator for reflecting the laser light transmitted through the optical fiber to the side at a tip portion of the optical fiber;
A double-structure balloon provided at the distal end of the catheter and having a first balloon and a second balloon provided to enclose the first balloon;
A first lumen for injecting a first fluid in communication with the interior of the first balloon;
A second lumen for injecting a second fluid into the space in communication with the proximal end of the catheter into a space formed by the outer surface of the first balloon and the inner surface of the second balloon;
A third lumen communicating with the space at a distal end of the catheter and for collecting a second fluid injected from the second lumen.

Moreover, the therapeutic apparatus by the other aspect of this invention for achieving the said objective is equipped with the following structures. That is,
A treatment device for heating and expanding a body cavity using the hot balloon catheter described above,
A light source for generating the laser light;
Injecting the first fluid into the first lumen by an indeflator causes the second fluid to flow through the second lumen while maintaining a pressure in the space that is greater than the pressure applied to the first balloon. Injection / recovery means for injecting more and recovering via the third lumen;
And control means for generating the laser light from the light source while allowing the second fluid to flow back through the space by the injection / collection means.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to implement | achieve dilation while heating the required site | part of a body cavity, without giving unnecessary heat damage to a biological body.

It is a figure which shows the structural example of the treatment apparatus by embodiment. It is a figure which shows the structural example of the hot balloon catheter by embodiment. It is a figure explaining the balloon of the double structure by embodiment. It is a figure explaining the expansion pressurization and heating process using a hot balloon catheter. It is a flowchart explaining the expansion pressurization by the embodiment, and a heating process. It is a figure explaining vascular dilation.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a diagram illustrating a configuration example of a treatment apparatus using a hot balloon catheter according to the present embodiment. In the treatment apparatus 100, the laser light source 101 generates laser light having a wavelength (for example, 800, 1300, 1500 nm) that is less absorbed by the living body. The laser light having a wavelength that is less absorbed by a living body is, for example, one having a dye absorption coefficient of 3 μm or less, such as water or hemoglobin, which is the main absorber of the living body. The controller 102 includes a memory (not shown), a CPU, and the like, and controls the laser light source 101, the scanner unit 103, and the light absorption liquid supply / recovery unit 300. The scanner unit 103 is attached with the hot balloon catheter 200 and transmits the laser light output from the laser light source 101 to the optical fiber in the hot balloon catheter 200. In addition, the scanner unit 103 rotates in the axial direction of the optical fiber and the rotation operation (radial operation) of a light irradiation unit (a drive shaft 218 and a side irradiation lens 217 described later) in the hot balloon catheter 200 under the control of the controller 102. Move (pullback operation).

  The overall configuration of the hot balloon catheter 200 will be described with reference to FIG. The hot balloon catheter 200 of the present embodiment has a double structure balloon 201 that can be expanded on the distal end side thereof.

  As shown in FIG. 2A, the hot balloon catheter 200 is disposed on the user's hand side without being inserted into the blood vessel for operation by the user, and a long catheter sheath 211 inserted into the blood vessel. Connector 212. A guide wire lumen 220 is formed at the distal end of the sheath, and the catheter sheath 211 is formed as a continuous lumen from a connection portion with the guide wire lumen 220 to a connection portion with the connector 212. Reference numeral 221 denotes a guide wire. By moving the hot balloon catheter 200 along the guide wire 221, the double-structure balloon 201 can reach a desired treatment site in the blood vessel. Therefore, the guide wire lumen 220 receives the guide wire 221 inserted in the body cavity in advance, and is used to guide the catheter sheath 211 to the affected part by the guide wire 221.

  The connector 212 includes a sheath connector 212a configured integrally with the proximal end of the catheter sheath 211 and a drive shaft connector 212b provided at the proximal end of the drive shaft 218 and configured to rotatably hold the drive shaft 218. Become. An anti-kink protector 213 is provided at the boundary between the sheath connector 212a and the catheter sheath 211. Thereby, a predetermined rigidity is maintained, and bending (kink) due to a rapid change can be prevented. The proximal end of the drive shaft connector 212 b constitutes an adapter that can be connected to the scanner unit 103.

  A double-structure balloon 201 that can be inflated by fluid injection is provided on the distal end side of the catheter sheath 211 and in front of the guide wire lumen 220. The double structure balloon 201 has a double structure as shown in FIG. 3 (details will be described later with reference to FIG. 3). The sheath connector 212 a is provided with ports 214 to 216 for connection with the inflator 400 and the supply and recovery unit 300. Each of the ports 214 to 216 communicates with an inner balloon or an outer balloon of a double structure balloon (described later with reference to FIG. 3).

  The drive shaft 218 has an optical fiber for guiding laser light from the laser light source 101 inside, and a side irradiation lens 217 is provided at a tip portion thereof. The side irradiation lens 217 reflects the laser beam reflected in the direction substantially perpendicular to the axial direction of the optical fiber and irradiates it by reflecting the laser beam transmitted through the optical fiber. The drive shaft 218 and the side irradiation lens 217 form a light irradiation portion for irradiating the laser beam output from the laser light source 101 toward the inner wall of the balloon. The light irradiation unit is capable of moving the catheter in the axial direction (pullback operation) and rotating about the axial direction (radial operation) inside the catheter sheath 211 of the hot balloon catheter 200. In other words, the drive shaft 218 is rotationally driven by the scanner unit 103, whereby the laser beam can be scanned radially within the double structure balloon 201. Further, the drive shaft 218 is inserted so as to be slidable relative to the catheter sheath 211 as shown in FIG.

  FIG. 2B is a diagram illustrating a state in which the drive shaft 218 is slid relative to the catheter sheath 211. As shown in the figure, when the sheath connector 212a is fixed and the drive shaft connector 212b is slid in the proximal direction (in the direction of the arrow 250), the sheath connector 212a is fixed to the internal drive shaft 218 or its distal end. The side irradiation lens 217 slides in the axial direction. This axial slide (pull-back operation) may be performed manually by the user or electrically by the scanner unit 103. A protective inner tube 251 is provided on the distal end side of the drive shaft connector 212b so that the rotating drive shaft 218 is not exposed.

  FIG. 3A and FIG. 3B are diagrams for explaining the details of the double structure balloon 201. The double-structured balloon 201 has an inner balloon 202 as a first balloon and an outer balloon 203 as a second balloon provided so as to enclose the inner balloon 202. With such a double structure, a space 204 is formed by the outer surface of the inner balloon 202 and the inner surface of the outer balloon 203. The material of the balloon is required to have pressure resistance and heat resistance, and examples of such a material include polyimide and nylon. However, the inner balloon 202 is configured to have a lower thermal conductivity than the outer balloon 203. For example, in addition to forming the inner balloon 202 with a material having low thermal conductivity, the film of the inner balloon 202 may be provided with a layer filled with gas (air) to lower the thermal conductivity.

  The port 214 communicates with the first lumen 214a. 3A, the first lumen 214a communicates with a space formed by the inner surface of the inner balloon 202. Accordingly, the fluid injected through the port 214 fills the space 205 inside the inner balloon 202. The ports 215 and 216 communicate with the second lumen 215a and the third lumen 216a, respectively, and these lumens communicate with the space 204 formed by the outer surface of the inner balloon 202 and the inner surface of the outer balloon 203, respectively. ing.

  As is clear from FIG. 3B, the second lumen 215a communicates with the space 204 on the proximal end side (connector 212 side) of the hot balloon catheter 200 to inject the second fluid into the space 204. Used for. The third lumen 216a communicates with the space 204 on the distal end side of the hot balloon catheter 200 and is used to collect the second fluid injected through the second lumen 215a. By adjusting the flow rate of the fluid continuously injected through the port 215 and the second lumen 215a and discharged from the port 216, the fluid can be recirculated while maintaining a predetermined pressure in the space 204.

  The first lumen 214a, the second lumen 215a, and the third lumen 216a are respectively provided in the catheter sheath 211, and are arranged as shown in FIG. 3C, for example. In this case, FIG. 3A is a view seen from the AA direction in FIG. 3C, and FIG. 3B corresponds to the view seen from the BB direction in FIG. In FIG. 3C, the fourth lumen 218a is a lumen through which the light irradiation unit (the side irradiation lens 217 and the drive shaft 218) passes.

  Returning to FIG. 1, the supply and recovery unit 300 is configured to recirculate the light absorbing liquid in the space 204 between the inner balloon 202 and the outer balloon 203. The supply tank 301 stores the light absorbing liquid which is the second fluid. The light absorbing liquid contains a dye having an absorption peak with respect to the wavelength of the laser light output from the laser light source 101. The pump 302 sends the light absorbing liquid stored in the supply tank 301 into the space 204 through the port 215. The on-off valve 303 opens and closes the flow path between the pump 302 and the port 215 under the control of the controller 102. The recovery tank 304 contains the light absorbing liquid that is injected into the space 204 via the port 215 by the pump 302 and recovered via the port 216. The on-off valve 305 controls the flow rate in the flow path leading from the port 216 to the recovery tank 304 under the control of the controller 102. The pressure gauge 306 measures the pressure of the light absorbing liquid in the flow path between the port 216 and the on-off valve 305 and transmits the measurement result to the controller 102. Thus, the recovery unit including the third port 216, the on-off valve 305, and the pressure gauge 306 constitutes a pressurizable system.

  The indeflator 400 is connected to the port 214 and injects the first liquid into the space 205 inside the inner balloon 202. The liquid injection by the inflator 400 may be performed manually or automatically by the controller 102. The on-off valve 305 has a function of switching the fluid flow path to either a flow path directly toward the recovery tank 304 or a flow path toward the pump 307. When the double structure balloon 201 is deflated after the treatment is finished, the fluid in the inner balloon 202 is extracted by the indeflator 400 and the flow path of the on-off valve 305 is switched to the pump 307 side. The fluid in 204 is withdrawn. In addition, the structure which extracts the fluid in the space 204 automatically by such a mechanism for switching the flow path to the pump 307 and the pump 307 is an option. For example, an indeflator may be connected to the flow path (or port 216) to the recovery tank 304, and the fluid in the space 204 may be manually extracted.

  A treatment for expanding a stenosis site in a blood vessel by the treatment apparatus 100 of the present embodiment having the above-described configuration will be described. FIG. 6 is a view for explaining the outline of the dilatation treatment of the vascular stenosis site by the hot balloon catheter 200. In a state where the double structure balloon 201 is deflated, the catheter sheath 211 is advanced along the guide wire 221 through the blood vessel 10, and the catheter sheath 211 is fixed at the position of the stenosis site 12 to be treated (FIG. 6). (A)). Subsequently, the stenotic region 12 is expanded by the double-structure balloon 201 while heating with laser light in the procedure described later with reference to FIGS. 4 and 5 (FIG. 6B). In this way, after expansion, the living body is cooled, and the double-structure balloon 201 is contracted and extracted again, so that the state in which the stenosis region 12 is expanded as shown in FIG. 6C is maintained.

  FIG. 4 is a diagram schematically showing fluid injection control to a balloon and heating control by laser light in an expansion procedure. FIG. 5 is a flowchart showing a procedure of fluid injection control to the balloon and heating control by laser light in the expansion treatment by the treatment apparatus 100 of the present embodiment.

  First, in S501, the inflator 400 injects the first fluid into the space 205 inside the inner balloon 202 via the port 216 and the first lumen 214a (FIG. 4A). The first fluid has a characteristic of applying an expansion pressure for expanding the blood vessel to the blood vessel wall and not absorbing the laser light output from the laser light source 101. Since a laser having a wavelength that is not absorbed by the living body is used, in the present embodiment, physiological saline having light absorption characteristics similar to those of the living body is used as the first fluid, but the present invention is not limited to this. At this stage, both the on-off valve 303 and the on-off valve 305 are closed. Further, the pressure for expanding the inner balloon 202 by the first fluid at this time is preferably about 1 to 5 atm, and most preferably about 2 atm. The liquid injection by the inflator 400 may be performed manually, or may be automatically performed by the controller 102 under pressure monitoring.

  Next, in S <b> 502, the controller 102 drives the pump 302 and opens the on-off valve 303, whereby the light absorbing liquid stored in the supply tank 301 is stored in the space 204 formed by the outer balloon 203 and the inner balloon 202. Is injected (FIG. 4B). Here, the light-absorbing liquid injected into the space 204 absorbs light of a specific wavelength (the wavelength of the laser light output from the laser light source 101) and generates heat, and the absorption characteristics change due to the generated heat. For example, a liquid containing a dye that absorbs light of a specific wavelength and generates heat and decolorizes after the heat generation is used. By selecting a laser beam having a wavelength that is less absorbed in the living body and matching the wavelength of the absorption peak of the light-absorbing liquid with the wavelength of the selected laser beam, heat is generated from the light absorber, and the laser beam is It is possible to prevent heating even when the living body is irradiated.

  As an example of a combination of such a laser beam and a light absorbing liquid, a combination of a laser beam having a wavelength of 800 nm and indocyanine green (ICG) having an absorption peak in the vicinity of the wavelength of 800 nm can be given. ICG is a test drug intended for administration to blood vessels used for liver function tests, and is already readily available at medical sites.

  In S <b> 502, the space 204 is pressurized by the ICG solution injected by the pump 302 by closing or flow rate control by the on-off valve 305, or pressure loss of the third lumen 216 a. As a result, the space 204 is formed from the collapsed state between the inner balloon 202 and the outer balloon 203. The controller 102 monitors the pressure in the space 204 with the pressure gauge 306, and determines whether or not the inside of the space 204 has reached a predetermined pressure in S503. When it is detected that the predetermined pressure is reached, in step S504, the controller 102 controls the on-off valve 306 to start collecting the ICG solution while maintaining the predetermined pressure. In S504, when the on-off valve 305 is closed and the ICG solution injection is started, the on-off valve is opened and the space 204 is maintained at a predetermined pressure. When the space 204 is pressurized by flow control without closing the on-off valve 305, the on-off valve 305 is controlled to maintain the pressurization in S504. When only the pressure loss of the third lumen 216a is used, the amount of ICG solution transported by the pump 302 is adjusted to maintain the space 204 at a predetermined pressure. In this case, the flow rate is controlled by the open / close valve 303, and the open / close mechanism and flow rate control mechanism of the open / close valve 305 are not required.

As described above, the controller 102 recirculates ICG while maintaining the pressure in the space 204 by controlling the flow rate by the on-off valve 306 (or on-off valve 303) while checking the pressure indicated by the pressure gauge 306. Here, the pressure in the space 204 is set to a pressure larger than the pressure applied to the inner balloon 202 by injecting the first fluid through the first lumen 214a by the indeflator 400. For example, in this embodiment, the pressure in the space 205 is approximately 2 atmospheres, and the pressure in the space 204 is approximately 2 to 5 atmospheres. In addition, the pressure in the space 204 is the pressure measured by the pressure gauge 306 as the recovery unit pressurization pressure generated by adjusting the flow rate of the on-off valve 305.
[Internal pressure of space 204] = [pressure loss of third lumen 216a] + [recovery part pressurizing pressure]
Thus, it can be seen that the internal pressure of the space 204 can be adjusted by the on-off valve 305.

  In step S505, the controller 102 starts laser output from the laser light source 101 and starts heating. At this time, the controller 102 controls the scanner unit 103 to rotate the drive shaft 218 (radial operation) and move the drive shaft 218 in the axial direction of the catheter (pullback operation) as shown in FIG. ) Note that the rotation of the light irradiation unit is, for example, 1800 rpm, and the pullback speed is, for example, about 5 mm / 20 seconds.

  This situation is shown in FIG. The state where ICG is refluxed is indicated by a small arrow in FIG. The ICG in the laser light irradiation portion 401 is decolored by absorbing the laser light and generating heat, and the light absorption characteristics change. Due to this heat generation, the laser light irradiation portion 401 is heated. This heat is transmitted to the blood vessel wall, and heating necessary for the blood vessel dilation treatment is performed. A desired part in the blood vessel can be heated by causing the drive shaft 218 to perform a radial operation and a pull-back operation while turning on / off the laser light irradiation.

  The decolorized ICG is discharged to the recovery tank 304 through the third lumen 216a. The decolorized ICG has a characteristic transparent to the laser beam, and even when irradiated with the laser beam while passing through the third lumen 216a, the ICG is not absorbed. Therefore, the laser light is not hindered by the ICG (after decoloring) passing through the third lumen 216a, and the ICG in the space 204 can be efficiently irradiated. In particular, if laser light irradiation is performed while rotating the light irradiation portion, most of the ICG downstream (distal end side) from the laser light irradiation position is already decolored, and most of the ICG passing through the third lumen 216a is also decolorized. It will be done.

  In addition, when laser light is irradiated to a portion where the ICG becomes transparent, the laser light reaches the living body almost as it is, but since the laser light has a wavelength that is difficult to be absorbed in the living body, Will not be heated. Also, in the space 204, only the ICG at the position irradiated with the laser light generates heat, so that the desired range of the living body can be heated by controlling the rotation and pullback of the drive shaft 218 described above.

  After the heating treatment is performed as described above, when the user instructs the end of the heating, the process proceeds from S506 to S507. In step S <b> 507, the controller 102 closes the on-off valve 303 and connects the flow path of the on-off valve 305 to the pump 307 to extract the ICG solution in the hot balloon catheter 200 from the on-off valve 303. Note that the fluid in the inner balloon 202 is manually extracted by the indeflator 400. Further, when the ICG solution is extracted by connecting the indeflator to the port 216 without providing the pump 307, it is only necessary to close the on-off valve 303 in S507.

  As described above, according to the treatment apparatus of the present embodiment, the living body is heated by the heat generated in the space 204 of the double structure balloon 201 having a double structure composed of two balloons being transmitted to the living body. That is, the surface of the double structure balloon 201 is heated, and the blood vessel wall is heated from the inner surface of the blood vessel by heat conduction. Therefore, compared with the conventional laser balloon and RF balloon, the thermal damage of the deep part of a biological body can be suppressed. Further, as described above, local heating is possible, and there is no need to heat a wide area unnecessarily like an RF balloon. In addition, the second fluid (ICG solution in this embodiment) flowing through the space 204 generates heat instantaneously upon irradiation with laser light because the volume of the irradiation portion 401 is small. Further, when the irradiation of the laser beam is stopped (when the heating is stopped), a cooling effect equivalent to that of performing liquid cooling by refluxing the ICG solution in the space 204 is obtained. For this reason, the temperature of the blood vessel wall can be raised and lowered quickly, and it not only functions to suppress thermal damage in the deep part, but also shortens the treatment time for vasodilation and the like.

Claims (8)

A hot balloon catheter for dilating while warming a body cavity,
A light irradiator having an optical fiber for guiding laser light for heating; and a side irradiator for reflecting the laser light transmitted through the optical fiber to the side at a tip portion of the optical fiber;
A double-structure balloon provided at the distal end of the catheter and having a first balloon and a second balloon provided to enclose the first balloon;
A first lumen for injecting a first fluid in communication with the interior of the first balloon;
A second lumen for injecting a second fluid into the space in communication with the proximal end of the catheter into a space formed by the outer surface of the first balloon and the inner surface of the second balloon;
A hot balloon catheter comprising: a third lumen communicating with the space at a distal end of the catheter and for collecting a second fluid injected from the second lumen.   The hot balloon catheter according to claim 1, wherein the first balloon is configured to have a lower thermal conductivity than the second balloon.   3. The hot balloon catheter according to claim 1, wherein the light irradiation unit is capable of moving in the axial direction of the catheter and rotating around the axial direction inside the catheter. 4. A treatment apparatus for heating and expanding a body cavity using the hot balloon catheter according to any one of claims 1 to 3,
A light source for generating the laser light;
Injecting the first fluid into the first lumen by an indeflator causes the second fluid to flow through the second lumen while maintaining a pressure in the space that is greater than the pressure applied to the first balloon. Injection / recovery means for injecting more and recovering via the third lumen;
A treatment device comprising: control means for generating the laser light from the light source while allowing the second fluid to flow back through the space by the injection / recovery means. The laser beam has a wavelength at which absorption and heat generation by a living body do not occur,
The first fluid does not absorb the laser beam;
The treatment apparatus according to claim 4, wherein the second fluid has a characteristic of absorbing the laser light to generate heat and decoloring due to the absorption, so that the laser light does not absorb.   The treatment device according to claim 4 or 5, wherein the control unit further irradiates the laser light while rotating the light irradiation unit about the axial direction of the catheter.   The treatment apparatus according to any one of claims 4 to 6, wherein the laser beam has a wavelength of 800 nm, and the second fluid is indocyanine green. A method for controlling a treatment apparatus for heating and expanding a body cavity using the hot balloon catheter according to any one of claims 1 to 3,
Injecting the first fluid into the first lumen by an indeflator causes the second fluid to flow through the second lumen while maintaining a pressure in the space that is greater than the pressure applied to the first balloon. An injection / recovery step of injecting and recovering via the third lumen;
And a control step of controlling the light source that generates the laser light while causing the second fluid to recirculate through the space by the injection / recovery step, thereby generating the laser light. .

Images