Laser perforator.

ES 2 173 909 T3

DESCRIPTION

Laser perforator.

This application is a continuation in part of pending US Patent No. 07 / 968,862 filed October 28, 1992.

Scope of the invention

This invention belongs to the field of medical equipment, that is to say laser medical equipment.

Background

The traditional procedure for collecting small amounts of blood from a patient uses mechanical piercing of the skin with a sharp device, such as a metal scalpel or needle. This procedure has many disadvantages, two of which are the possible infection of healthcare workers or the general public with the device used to pierce the skin and the costly handling and disposal of biologically hazardous waste.

When the skin is pierced with a sharp device, such as a metal knife or needle, the biologic residue is created in the form of the “sharp item” that is contaminated by the patient's blood or tissue. If the patient is infected with any of a number of agents that appear in the blood, such as the human immunodeficiency virus (HIV-Human Immunodeficiency Virus) that causes the acquired immunodeficiency syndrome (AIDS-Autoimmune Deficiency Syndrome), the hepatitis virus, or the etiological agent of other diseases, the sharp element can pose a serious threat to others who must be in contact with it. There are many documented cases of HIV infections by healthcare workers who were accidentally injured with a contaminated sharp item.

The removal of sharp elements is also a major problem. Disposal of contaminated materials poses both a logistical problem and an economic burden to the end user, such as the medical institution. In the 1980s there were numerous cases of improperly treated biological waste washed up on public beaches. The potential for other people, such as intravenous drug users, to obtain improperly discarded needles is also problematic.

There is an additional disadvantage to the traditional procedure of being injured by a sharp instrument for the purpose of drawing blood. Often times, the procedure of producing the wound has to be repeated before obtaining enough blood. This causes significant tension and distress to the patient.

Obviously, the current procedure for piercing the skin for the purpose of drawing blood has significant inherent problems. These problems appear because a sharp instrument is used in the process. Therefore, there is a need for a technique for piercing the skin that does not use a sharp element. This procedure avoids the need to dispose of contaminated instruments and reduces the risks of cross-infection.

Lasers have been used in recent years as a highly accurate and effective tool for a variety of surgical procedures. Among the potentially new sources of laoser radiation, rare earth elements are of the greatest interest to medicine. The most promising one of them is a YAG crystal (Ytriumaluminum garnet - Yttrium Alumino Garnet) contaminated with erbium ions (Er). With the use of this crystal, it is possible to build an erbium-YAG (Er: YAG) laoser which can be configured to emit electromagnetic energy at a wavelength (2.94 microns) which is strongly absorbed by water. When a tissue, which consisted mainly of water, with radiation at or near this wavelength, is irradiated, it heats up rapidly. If the intensity of the radiation is sufficient, the heating is rapid enough to cause vaporization of the tissue. Some medical uses of Er: YAG lasers have been described in the disciplines of dentistry, gynecology, and ophthalmology. See, for example "The effect of YAG: Er laoser radiation on hard and soft tissues" by Bogdasarov et al., Prepint 266, Institute of General Phosphics, Moscow, 1987; "Experimental foundations for the application of the YAG: Er laser" by Bol'shakov, EN et al., SPIE 1353: 160-169, lasers and medicine (1989). Summary of the invention

This invention uses a laser beam to pierce the skin of the patient. Perforation occurs by radiating the surface of the skin through a focused pulse of electromagnetic energy emitted by the laser. It is possible to drill the skin very precisely to a depth that can be selected without causing clinically relevant damage to healthy proximal tissue, by prudent selection of the following irradiation parameters: wavelength, energy fluence (determined by dividing the energy of the impulse by the radiated area), the temporal duration of the impulse and the size of the irradiation point.

A device is provided that emits a pulsed laser beam focused to a small spot for the purpose of piercing tissue. By adjusting the output of the laoser, the depth, width and length of the perforation can be controlled to suit the purpose for which the perforation is required. This procedure can be used to create a small, relatively narrow hole in the skin which penetrates into the capillary bed, thereby allowing the collection of blood for a variety of purposes. Optionally, a tissue prewarming device can be added to increase blood flow prior to perforation with the laoser. Safety interlocks are advantageously incorporated to prevent dangerous operation and accidental irradiation of the laoser.

This device can be further modified to include a container. Such a container can be added to: (1) increase the yield in the collection of blood and serum; (2) reduce the noise created when the beam

ES 2 173 909 T3 laser pierces the patient's tissue; and (3) collecting the eroded tissue. The container is optionally evacuated to speed up the collection of blood and serum. In one embodiment, the container uniquely collects the eroded tissue. The noise created from the interaction of the laser beam with the patient's skin can cause distress to the patient. The optional container reduces the intensity of the noise and thus alleviates the distress and stress of the patient. The container also minimizes the risk of cross contamination and guarantees the sterility of the collected sample. The placement of the container in the device of this invention is unique since it covers the tissue that is being perforated at the time of perforation by the laser beam and therefore is capable of collecting the blood sample and the eroded tissue when the perforation occurs. perforation.

This invention also provides a means of piercing a patient's skin in a non-bleeding manner. Typically created perforation penetrates through the keratin layer or both, the keratin layer and the epidermis. This will allow the administration of pharmaceuticals through the skin. There are many advantages in administering medications in this way, for example: medications can be continuously administered to an outpatient for long periods of time and the speed and performance of the medication delivered can be improved for medications that are slow or slow. unable to penetrate through the skin. In addition, this administration procedure provides an alternative route of administration for medications that would otherwise require injection.

This invention avoids the use of sharp elements. The absence of a contaminated sharpened item will eliminate the risk of accidental injury and related risks to healthcare workers, the patient, and anyone who may come into contact with the sharpened item, either by accident or necessity.

The absence of sharp elements also avoids the need to remove biohazard waste. Therefore, this invention provides an ecologically safe procedure of piercing the skin.

The device of this invention does not require special skills to use it. It is small, light in weight, and can be used with rechargeable batteries. This mobility and ease of use makes it possible to use the device in a variety of settings, such as a hospital room, clinic or home.

The safety features incorporated into this device do not require that the operator of the device, the patient, or whoever is in the vicinity of the device when it is being used, wear any element of protection for the eyes. This is a considerable improvement over prior art laser devices which require special protection of this type.

L. Esterowitz et al. "Solid state Mid-IR laser with fiber optic as an ideal medical scalpel", in the proceedings of the conference on lasers, Las Vegas, 1985, pages 68-71, describe the use of an Er laser. : YAG that emits at 2.94 microns as a medical scalpel to irradiate biological samples. The use of flexible ZrF4 fibers to deliver laser radiation to the biological sample is also described. This device described herein comprises the characteristics of the preamble of claim 1.

US Patent No. 4,710,940 issued December 1, 1987 to Sipes, Jr., describes an optically pumped Nd: YAG laser.

American patent application A-0 214 712, "Infrared catheter system", describes laser catheter systems that work with mid-infrared radiation, including Er: YAG lasers and fiber-optic systems to generate and transmit energy to a site. surgical with the purpose of removing or healing tissue.

Brief description of the drawings

The present invention will be better understood and its advantages will be appreciated by those skilled in the art with reference to the accompanying drawings, in which:

Figure 1 shows the laser device with its power source, high voltage pulse formation network, flash lamp, laser rod, mirrors, housing and focusing lens.

Figure 2 shows an optional spring loaded interlock and an optionally heated applicator.

Figure 3 shows alternative means of driving the laser wand using a laser diode.

Figure 4 shows an alternative focusing mechanism.

Figure 5A shows multiple optional beam splitters such as partially silver mirrors, dichroic mirrors, or beam splitters to create multiple simultaneous perforations. Figure 5B shows an optional water-optic modulator with modulated high voltage to actuate the modulator and deflect the beam to create multiple simultaneous perforations.

Figure 6 shows a patch that can be used to sterilize the perforation site.

Figure 7A shows a patch for sterilization and delivery of pharmaceuticals. Figure 7B shows a patch with an optional laser transparent material such as mica, quartz or sapphire which is transparent to the laser beam in the center of the patch.

Figure 8 shows an optional container to collect blood and eroded tissue and to reduce noise that results from interaction between the laser and the patient's tissue.

Figure 9 shows a plug and the hole center of the plug.

Figure 10 shows an optional container for collecting eroded tissue and reducing noise resulting from interaction between the laser and the patient's tissue.

Figure 11 shows an optional version of the collection container which is especially useful when the container includes a reagent for mixing with the blood.

ES 2

Detailed description of the preferred embodiments

This invention provides a method and device for piercing the skin, both for collecting blood samples and for administration of pharmaceuticals. The device uses a laser beam, specifically focused and emitting at an appropriate wavelength, preferably between 2 and 7 microns, to create small holes in the patient's skin. The laser beam is focused with a lens to produce an irradiation spot on the skin of a size of approximately 0.1-1 mm in diameter and an energy fluence in the range of 10-10,000 j / cm.²Optionally, the point can be slit-shaped with a width of 0.05-0.5 mm and a length of up to 2.5 mm.

The device

As shown in the figures, the device comprises a power connection which can be both a standard electrical supply 10, and optionally a battery pack that can be recharged 12, optionally with a power interlock switch 14 for purposes of security; a high voltage impulse formation network 16; a laser pump cavity 18 containing a laser wand 20, preferably Er: YAG; means for exciting the laser wand, preferably a flash lamp 22 held within the cavity of the laser pump; an oaptic resonator comprising a high reflectance mirror 24 positioned behind the laser wand and an output coupling mirror 26 positioned before the laser wand; a transmission focusing lens 28 positioned beyond the output coupling mirror; optionally, a second cylindrical focusing lens 27 positioned between the output coupling mirror and the transmitting focusing lens; an applicator 30 for positioning the subject's skin at the focal point of the laser beam, optionally heated for example with a thermoelectric heater 32, attached to the laser housing 34; an interlock 36 positioned between the applicator and the power supply and optionally a beam discharger 38 attached to the applicator with a button access port 40.

Figures 1-2 are schematic representations of the preferred embodiment of the device of the invention. The device preferably draws energy from a normal 110 V or 220 V line, 10 (one phase, 50 or 60 Hz) which is rectified and used to charge a bank of capacitors included in the high voltage impulse formation network 16 Optionally, you can use a battery pack that can be recharged 12. The capacitor bank establishes a high direct current voltage across the high output flashlamp 22. Optionally, a power interlock 14, such as a contact lock, may be provided which will prevent accidental charging of the leads. capacitors and therefore accidental excitation of the laser. An additional interlock on the applicator, such as a spring loaded interlock 36, may be added to the device such that discharge of the capacitors requires both interlocks to allow it.

909 T3 6

By pressing a switch, a voltage pulse can be superimposed on the voltage already existing through the flashlamp to cause the flashlamp to conduct and consequently initiate the flash. The light from the flashlamp is positioned in the laser cavity 18 which is shaped such that most of the light is effectively directed at the laser rod 20, which absorbs the light and, when excited, emits the laser. due. The low reflectance 26 and high reflectance laser cavity mirrors positioned collinear with the long axis of the laser, serve to amplify and align the laser beam.

Optionally, as shown in Figure 3, a diode laser 42 which produces a pump beam collinear with the long axis of the laser crystal can be used in place of the flashlamp to drive the crystal. The pump beam of this laser is collimated with collimating lenses 44 and is transmitted to the primary laser rod through the high reflectance infrared mirror 45. This high reflectance mirror allows the diode pump laser beam to be transmitted while reflecting infrared light from the primary laser.

The Er: YAG laser material is the preferred material for the laser rod, because the wavelength of the electromagnetic energy emitted by this laser 2.94 microns, is very close to one of the absorption wavelength peaks. (about 3 microns) from the water. Therefore, this wavelength is strongly absorbed by water. Rapid heating of the water causes perforation of the skin.

Another useful material to emit the laser is any material that, when induced to emit the laser, emits at a wavelength that is strongly absorbed by the tissue, such as through absorption by water or nucleic acids or proteans. and consequently causes the required perforation of the skin. A laser can effectively cut through tissue to create desired perforations where the tissue exhibits an absorption coefficient of 10-10,000 cm.^-1. Examples of portable elements that emit lasers are CO2 pulsed lasers, Ho: YAG (holmium: YAG), Er: YAP, Er / Cr: YSGG (erbium / chromium: yttrium, scandium, gallium, garnet; 2.796 microns), Ho: YSGG (holmium: SIG; 2.088 microns), Er: GGSG (erbium: gadolinium, gallium, scandium, garnet), Er: YLF (erbium: yttrium, lithium, fluoride; 2.8 microns), Tm: YAG (thulium : YAG; 2.01 microns), Ho: YAG (holmium: YAG; 2.127 microns); Ho / Nd: YAIO3 (holmium / neodymium: yttrium, aluminate; 2.85-2.92 microns), Cobalt: MgF2 (Cobalt: Magnesium, Fluoride; 1.75-2.5 Microns), Chemical HF (Hydrogen Fluoride; 2.6-3 Microns), Chemical DF (Deuterium Fluoride ; 3.6-4 microns), carbon monoxide (5-6 microns), deep UV lasers and triplicate frequency Nd: YAG (neodymium: YAG, where the laser beam passes through crystals which cause the frequency tripled).

Using normal technology, some of these laser materials provide the added benefit of small size, allowing the laser piercing device to be small and portable. In addition to Er: YAG, Ho: YAG lasers provide this advantage.

ES 2 173 909 T3

The emitted laser beam is focused down to a point of a size of one millimeter or less than one millimeter with the use of focusing lenses 28. Considerations regarding layser safety issues suggest that short focal length focusing lenses be used. to ensure that the energy flow rate (w / cm²) is low except at the lens focus where the tissue sample to be drilled is positioned. Consequently, the danger of the laser beam is minimized.

The beam can be focused so that it is narrower along one axis than the other in order to produce a slit-shaped perforation by using a cylindrical focusing lens 27. This lens, which focuses the beam along an axis, it is placed in series with the transmission focusing lens 28. When perforations are slit-shaped, the damage associated with perforation is greatly reduced.

Optionally, the beam may be broadened, for example, through the use of a coincave divergence lens 46 (see Figure 4), prior to focusing through the focusing lens 28. This broadening of the beam results in a beam layser with an energy fluence rate even lower at a short distance beyond the focal point, consequently reducing the level of danger. Furthermore, this optic arrangement reduces optic anomalies at the layser point at the treatment position, consequently resulting in more precise drilling.

Also optionally, the beam can be split by means of a beam splitter to create multiple beams capable of drilling at various locations simultaneously or nearly simultaneously. Figure 5 provides two useful variations of beam splitters. In one version, multiple beam splitters 48 such as partially silver mirrors, dichroic mirrors, or beam splitters may be provided after the beam has been focused. Alternatively, a water-optic modulator 52 may be supplied with modulated high voltage to drive modulator 52 and deflect the beam. This modulator is outside the lyser cavity. It works by rapidly deflecting the laser beam at a variety of angles to simulate the production of multiple beams.

A small heater, such as a thermoelectric heater 32, is optionally located at the end of the laser applicator close to the location of the perforation. The heater raises the temperature of the skin and capillaries to be pierced prior to irradiation with the laser. This increases blood flow, which increases the volume of blood collected when the device is used for that purpose. A suggested range of skin temperatures is between 36 ° C and 45 ° C, although any temperature that causes vasodilatation and the resulting increase in blood flow without altering the chemical composition of the blood is appropriate.

A container 68 is optionally fitted within the laiser housing and is positioned near the drilling site. The container reduces the intensity of the noise produced when the laser beam pierces the patient's tissue, increases blood collection performance, and collects eroded tissue. The container is shaped such that it allows easy insertion into the laser housing and provides a frictional fit within the laser housing. Figure 8 shows the container inserted into the lyser housing and positioned on the perforation site.

The shape and size of the container are such as to allow insertion into the applicator and to collect the blood sample and eroded tissue. Preferably the container is bullet shaped with a volume of about 1.5 milliliters.

In the preferred embodiment, the container is constructed of glass or plastic. In one embodiment, a vacuum has been made in the container. The optional vacuum in the container exerts negative pressure on the perforation site, thereby increasing blood collection performance. The container is optionally lined with anticoagulant chemicals and preservatives. Examples of preservatives include ethylenediaminetetraacetic acid (EDTA) or sodium benzoate. Examples of blood thinning chemicals are sodium heparin and sodium citrate.

The end of the container near the drilling site is optionally airtight sealed with a plug 70. The plug 70 is made of material of adequate flexibility to conform to the contours of the drilling site (for example, a finger ). The desired hole location is pressed firmly against the plug. The plug material is impervious to gas transfer. In addition, the liner material is thin enough to allow perforation of the material as well as perforation of the skin by the layser. In the preferred embodiment, the cap is made of rubber.

The center of perforation of the plug 74, as shown in FIG. 9, is preferably made of thin rubber material. The thickness of the plug is such that the plug can hold the vacuum before drilling and the laiser can pierce both the plug and the tissue attached to the plug. To use with an Er: YAG layser, the cap must be in the range of approximately 100 to 500 microns thick, but not more than 1 millimeter thick.

The center of drilling of the plug 74 is large enough to cover the drilling site. Optionally, the drilled location is a round hole with an approximate diameter in the range of 0.1-1 mm, or slit-shaped with a width of approximately 0.05-0.5 mm and a length of approximately 2, 5 mm. Therefore, the center of drilling of the plug is large enough to cover drill sites of these sizes.

The drilling site is firmly pressed against the rubber material. Optionally, an adhesive ring can be placed on the rubber pad to provide 5

ES 2 173 909 T3 nar a hermetic seal between the drilling site and the container. Preferably, the location of the perforation in the plug is stretched when the fabric is pressed against the plug. This stretching of the plug material causes the hole created in the plug to extend beyond the size of the hole created in the fabric. As a result, blood and serum can flow unhindered into container 68.

Container 68 includes a window 72 that is made of an infrared transmitting material and is positioned in the laoser beam path at the end of the container near the beam. The laser beam penetrates the container through the window, pierces the center of perforation of the cap 74 and pierces the tissue of the patient. In the preferred embodiment, the infrared transmitting material is quartz, but other examples of suitable infrared materials include rock salt, germanium, and polyethylene.

In a second embodiment of the container, as shown in FIG. 10, the container 68 includes a hole 76 through which the laser passes. In this second embodiment, the container only collects the eroded tissue. As in the first embodiment, the drilling site is firmly pressed against the container. The container may optionally include a plug close to the location of the perforation, however, this is not essential because there is no need to maintain a vacuum in the second embodiment. Both embodiments of the container reduce the noise created by the interaction between the laser beam and the patient's tissue and thereby alleviate the anxiety and tension of the patient.

Optionally, the container is disposable, so that the container and cap can be disposed of after use. Additionally, the container can contain reagents for various tests carried out on the collected blood. Examples of such reagents are sodium heparin and other reagents known in the art for use in normal chemical analyzes of blood. See for example, Garza, D. and others, Manual of blood analysis (3^to edition) Appleton and Lang Pub. Co. Norwalk, CT, 1993, which is incorporated herein by reference. The reagents are positioned so that they are not in the laoser light path. The reagents are preferably present in dry form, coating the inside walls of the container and thus readily available for interaction with the blood sample being drawn.

A preferable configuration of the container when it contains a reagent is shown in Figure 11. In this configuration, the container has an indentation 78 in the base so that any fluid reagent present in the container does not fall into the fire line of the laser beam. when the container is held both vertically and horizontally. The appendix 80 of the area with the notch is made of an infrared transparent substance, such as quartz.

When reagents are present in the container prior to blood collection, it is beneficial to label the container in some way with the reagents contained within, or with the test to be carried out on the sample using those reagents. A preferred method of labeling for this type is through the use of color-coded caps. For example, a blue cap may indicate the presence of reagent A, while a red cap may indicate the presence of reagents B plus C inside the container.

In order to sterilize the skin prior to piercing, a patch of paper, or other thin material, impregnated with alcohol may optionally be placed on the site to be pierced. This material can also prevent potentially infected tissue from shedding on the thread released from the perforation. The material must be transparent to the laser beam. Examples of such materials are a thin layer of quartz, mica, or sapphire. Alternatively, a thin layer of plastic, such as a polyvinyl chloride film, can be placed on the skin. Although the laser beam will pierce the plastic, the plastic prevents part of the thread from shedding and therefore decreases any potential risk of contamination from infected tissue. Additionally, a layer of a sterile viscous substance, such as petroleum jelly, can be added to the transparent material or plastic film to increase the adhesion of the material or the plastic to the skin and further decrease the contamination of the yarn. Additionally, such a patch can be used to deliver allogeneic, local anesthesia, or other pharmaceuticals as described below.

Examples of such a patch are provided in Figures 6 and 7. In Figure 6, an alcohol impregnated paper 54 was surrounded by a temporary adhesive tape 58. Side views of two alternative patches are shown in Figures 7A and 7B , where sterilizing alcohol, antibiotic ointment, allergen or a pharmaceutical product are present in the central area of ​​the patch. This material is held in place by a layer of paper or plastic 62, optionally with a material transparent to the laser 64 (shown in Figure 7B) such as mica, quartz or sapphire which are transparent to the laser beam in the center. of the patch. The patch can be placed on the skin using an adhesive 66.

The factors to be considered when defining the laser beam are the wavelength, the energy fluence, the time duration of the pulse, and the size of the irradiation spot. The wavelength is determined by the laoser material used, such as Er: YAG used in the device. The duration of the impulse is a consequence of the amplitude of the impulse produced by the capacitor bank, the flashlamp and the material of the laser rod. The pulse width was optimally between 1 and 1,000 microseconds. The laser beam is precisely focused on the skin creating a slit-shaped focal point with a width in the range of 0.05 to 0.5 mm and a length of up to 2.5 mm, or a slit-shaped focal point. 0.26 ellipse

ES 2 173 909 T3

0.3 by 1-2 mm. The energy density, which is a function of the laser's energy output (in joules) and the size of the beam at the focal point (cm²), it should be in the range of 10-100,000 j / cm². The focal length of the lens can be any length but in one embodiment of the device it is 30mm. The energy flow rate is preferably in the range of 1.3 x 10⁴ up to 6.4 x10¹⁰ watts / cm² and at the same time the energy flow rate is preferably in the range of 1.3 x 10¹ up to 6.4 x 10⁷ watts / cm².

The device works as follows: the power interlock switch is turned on, thereby starting the charging of the capacitors. The device is manipulated in such a way that a part of the patient's skin is positioned at the location of the layser focus inside the applicator. For blood collection, placement of the perforation will be optimally at the site where blood flow is high. Examples of such skin regions are the fingertips or the heel of the foot. For piercing to administer anesthesia or pharmaceuticals or for immunization, a region of the skin that has less contact with hard objects or sources of contamination is preferred. Examples of this are the skin of the arms, legs, abdomen or back. Optionally, at this time the element is activated to heat the skin.

Preferably a bracket is provided with a hole that coincides with the focal plane of the ioptic system. Optionally, a spring loaded latch 36 may be attached to the holder so that when the patient applies a small amount of pressure to the latch, to embed it at the focal point, the switch is closed and the laser would initiate a pulse of radiation. In this setup, the focal point of the beam is not in line with the end of the bracket, until that end is pressed. In the unlikely extreme case of accidental discharge of the laser prior to proper placement of the tissue at the end of the laser applicator, the optical arrangement will result in an energy fluence rate that is significantly low, thereby causing negligible effect. on unintended targets.

For certain purposes, it is useful to create multiple skin perforations simultaneously or in a rapid sequence. To achieve this, a beam splitter can optionally be added to the device.

Blood or serum collection

The device can be used to pierce the skin down to the capillary layer to allow blood to be collected. Blood can be used for a wide variety of tests, such as determining the chemical composition of the blood (blood sugar, CBC, urea, electrolytes, creatinine, cholesterol, etc.) and can be fractionated into its components, such as serum and cells, for a wide variety of purposes, such as the determination of the number of red blood cells in the blood. Blood can also be used for genetic testing for genetic counseling.

With the other parameters set, the intensity of the laser pump source would determine the intensity of the laser pulse, which in turn would determine the depth of the resulting perforation. Therefore, various settings can be provided on the device to allow penetration of different thicknesses of skin.

As described above, the skin can be preheated to dilate capillaries and increase blood flow prior to perforation. This increased blood flow allows a larger volume of blood to be collected and avoids the need for multiple perforations. Preheating can be accomplished by the addition of a preheater, as described above, or by other means to preheat the skin prior to placement in the laser applicator portion of the device.

Optionally, a beam discharger is positioned in such a way that it does not impede the use of the laiser to puncture the fingertips of the hand. The beam discharger will absorb any stray electromagnetic radiation from the beam that is not absorbed by the tissue, thereby preventing scattered rays from causing damage. The beam discharger can be easily removed for situations where the presence of the beam discharger would prevent the placement of a part of the body in the applicator.

This procedure of drawing blood creates a very small area in which tissue vaporizes, and only an extremely small area of ​​skin necrosis is created. A practically round hole can vary in the range of 0.1-1 mm in diameter, while a slit-shaped hole can vary from about 0.050.5 mm in width to about 2.5 mm in length. As a result, the healing is either quick or as quick as the healing of a puncture in the skin with a sharp implant.

The blood can be collected into a suitable vessel, such as a small test tube or capillary tube, or into a container placed between the lyser and the tissue, as described above. The laser of this invention is particularly suitable for collecting blood because it does not clot the blood as it penetrates the skin. In addition, the process is carried out without contact and therefore neither the patient nor the blood that is extracted nor the instrument that creates the perforation are contaminated.

Administration of pharmaceutical products

By suitable modification of the energy level and the size of the laser beam spot, perforations can be made that do not penetrate the skin as deeply as described above. These piercings can be made through the outer surfaces only, such as the keratin layer or both, the keratin layer and the epidermis. Optionally, an ioptic beam splitter can be used so that both a single perforation and a series of perforations can be made in the desired area. After piercing, the drug may be administered to the skin in the form of a cream, lotion, or patch.

Immunization

As for the administration of pro7

ES 2 173 909 T3 pharmaceutical ducts, antigens can be administered through the skin for immunization purposes. Perforations are performed through the outer layers of the skin, both single and multiple, and the immunogen is provided in the appropriate formula. For booster immunizations in which administration over a period of time increases the immunization response, the immunogen can be provided in a formula that penetrates slowly through the perforations, but at a faster rate than would be possible through the perforations. of the skin without piercing.

Administration of anesthesia

Local anesthesia can be administered using the procedure and device of this invention. Topically applied anesthesia must penetrate the keratin layer in order to be effective. Currently, compounds that act as drug transporters are used to facilitate transdermal diffusion of some drugs. These transporters sometimes alter the behavior of the drug or are themselves toxic. The energy level of the appliance must be adjusted appropriately to penetrate the keratin layer but without penetrating the capillary layer. Anesthesia can be administered to the perforations for example in a patch impregnated with balsaimic ointment. Administration of allergens

This device and this procedure can also be applied to the administration of allergens, for example for allergy tests. Multiple perforations can be made through the outer layer of the skin, but without penetrating the level of the capillaries. A variety of allergens can then be applied to the skin, as in the case of a skin patch test.

The following examples are descriptions of the use of the device of this invention for the purpose of drawing blood. These examples do not mean a limitation to the scope of the invention but are merely an embodiment.

Example 1

An infrared laser radiation pulse was formed using a solid state, multimode pulse Er: YAG laser, consisting of two planar resonator mirrors, an Er: YAG crystal as the active medium, an energy supply, and means to focus the laser beam. The wavelength of the layser beam was 2.94 microns. The duration of the pulse was approximately 100 microseconds. The size of the elliptical spot was approximately 0.2-0.3 by 1-2 mm. The pulse energy used was 0.7, 0.9, or 2.0 j for thin to thick skin, respectively. Uine pulses were used, but in one test 6 pulses per minute were used, each irradiating a different part of tissue.

The operating parameters were the following:

The energy per pulse was 2 joules, with the beam size at the focal point being 0.2 mm, creating an energy fluence of 10³j / cm². The time duration of the pulse was 100 microseconds, creating an energy fluence rate of 1 x 10⁷ watts / cm².

Each toe of the patient was treated, prior to perforation, with 96% ethyl alcohol to kill bacteria. The finger was placed on the focal point of the liaser and the liaser was discharged. Blood was drawn from the perforation with a glass capillary tube. The volume of blood drawn (without squeezing the finger) varied between 0.5-1.0 ml. This blood did not differ chemically from comparable scalpel prick samples during control tests. The damage caused by the laser piercing was estimated to be equal to or less than the damage caused by the puncture when driving the scalpel.

The morphological analysis of the effect of the laser perforation in the skin tissue showed a minimal area of ​​thermal destruction (less than 20-40 microns beyond the edge of the perforation produced) without signs of charring. The wounds were cone-shaped. The depth and width of the wounds were found to be proportional to the energy fluence and were roughly related to the inverse of the duration of the laser pulse.

Example 2

The laser piercer comprises a flashlamp (PSC Lamps, Webster, NY), an Er: YAG crystal (Union Carbide Crystal Products, Washagoul, WA), oyptic resonator mirrors (CVI Laser Corp., Albuquerque, NM), a infrared transmission (Esco Products Inc., Oak Ridge, NJ), as well as numerous normal electrical components, such as capacitors, resistors, inductors, transistors, diodes, silicon-controlled rectifiers, fuses, and switches, which can be purchased from any electrical component supplier firm, such as Newark Electronics, Little Rock, AR.

Example 3

An infrared laser radiation pulse was formed using a solid state, multimode pulse Er: YAG laser consisting of two planar resonator mirrors, an Er: YAG crystal as the active medium, an energy supply, and means to focus the laser beam. The wavelength of the laser beam was 2.94 microns. The duration of the pulse was approximately 100 microseconds. The size of the elliptical spot was approximately 0.2-0.3 by 1-2 mm. The pulse energy used was 0.7, 0.9, or 2.0 j for thin to thick skin, respectively. Uine pulses were used, but in one test 6 pulses per minute were used, each irradiating a different part of tissue.

The operating parameters were the following:

The energy per pulse was 2 joules, with the beam size at the focal point being 0.2 mm by 1 mm, creating an energy fluence of 10³ j / cm². The time duration of the pulse was 100 microseconds, creating an energy fluence rate of 1 x 10⁷ watts / cm².

Each toe of the patient was treated, prior to perforation, with 96% ethyl alcohol to kill the bacteria. The finger was placed on the focal point of the laiser and the liaser was discharged. Blood was drawn from the perforation with

ES 2 173 909 T3 a glass capillary tube. The volume of blood drawn (without squeezing the finger) varies between 0.5-1.0 ml. This blood will not differ chemically from comparable samples obtained by scalpel prick during control tests. The damage caused by the laser piercing was estimated to be equal to or less than the damage caused by the puncture when driving the scalpel.

The morphologic analysis of the effect of the laser perforation on the skin tissue will show a minimal area of ​​thermal destruction (less than 20-40 microns beyond the edge of the perforation produced) without signs of charring. The wounds were slit-shaped. The depth and width of the wounds were found to be proportional to the energy fluence and were roughly related to the inverse of the duration of the laser pulse.

Example 4

Perforation will be performed as in Example 1 or 3, except that the device will be modified to include a tube for collecting blood, snugly fitted between the front end of the laser device and the focal point of the laser, through from which the laser beam will pass. The tube is 2.0 cm long and 1.0 cm in diameter, with a notch at the bottom which advances the bottom 1.0 cm into the center of the tube. As a result, any crystallized fluid or additive such as heparin sodium anticoagulant does not fall into the line of fire of the laser beam when the tube is held both vertically and horizontally. The appendix of the notched area is made of a quartz disc which is transparent to the laser beam.

The distal end of the tube is covered with a rubber plug. The rubber plug is coated on the outside with an adhesive to cause the plug to adhere to the skin to be pierced. The tube itself is kept vacuum inside before drilling. The tube is additionally coated inside with sodium heparin to act as an anticoagulant for the purpose of carrying out a blood count of the sample obtained.

The laser is then fired, causing the laser beam to pass through the tube, uniquely piercing the distal end (the plug) of the tube, as well as the skin. A blood sample of approximately 1 cc will then flow into the tube and mix with the sodium heparin. The entire blood sample as well as the burst / eroded tissue is therefore contained within the tube, avoiding contamination and the spread of diseases.

While the embodiments and applications of this invention have been shown and described, it will be apparent to those skilled in the art that many more modifications are possible without departing from the concept of the invention, as defined in the appended claims.