Patent Description:
Currently, surgery represents the gold standard to reduce skin laxity, but is invasive, costly, and inconvenient. Minimally invasive energy-based platforms offer an alternative to surgery, but are complicated with their own side effects. For example, present surgery alternatives like laser, radiofrequency, and ultrasound rely on devices that cause thermal damage to the tissue area being treated. This causes significant recovery time, delayed re-epithelialization, prolonged erythema, hypo- and hyper-pigmentation and, in some instances, scarring. Additionally, these surgery alternatives produce only modest efficacy after multiple treatments, have high patient-to-patient variability, and suffer from a significant non-responder rate. Other reported side effects include significant pain, bruising, tenderness, swelling, scabbing, and blistering.

Beside physical side effects, economic issues also hinder market growth. In particular, surgery is costly and requires treatments to be performed by a physician in an operating room. Additionally surgery alternatives generally require costly capital equipment, which limits market acceptance, revenue potential, and profitability.

Therefore, there exists a clinical need for a safe and effective treatment for reducing skin laxity and/or tightening other tissue types that is minimally invasive, convenient, and offers minimal downtime. <CIT> relates to methods, apparatuses, and devices for treating skin and proximal tissue layers, such as skin tightening. <CIT> relates generally to laser treatment of the skin and, more particularly, to a laser treatment inducing a chronic wound in the high dermis, leaving the epidermis intact, with topical pretreatment and post-treatment of the skin with retinoic acid. <CIT> relates to cosmetic methods and systems for improved fractional resurfacing of skin tissue and similar procedures, specifically, such methods and systems that facilitate enhanced and/or directional reduction in skin area or reduction of wrinkles. <CIT> relates generally to medical devices, kits and methods used for improved healing of skin after a therapeutic injury. For example, such devices, kits and methods can be used to produce improved tightening of skin after a therapeutic treatment. <CIT> relates to adhesive assemblies, or systems, comprising one or more layers, and microneedle injection apparatuses comprising such adhesive assemblies. <CIT> refers to a Laser therapy system mainly comprising a first light source in the UVA range, a second Laser light source with a second wavelength range, an optical system and a control and navigation unit by means of which light can be precisely focused and positioned and applied in the papillary dermis or in the sclera or conjunctiva of the eye. In addition, the invention comprises a method for collagen remodeling of the skin by means of said Laser therapy system.

The invention provides a kit for treating tissue and a non-therapeutic method for tightening or lifting skin tissue according to the independent claims. Preferred embodiments are laid down, among others, in the dependent claims.

The systems and methods of the present disclosure overcome the above and other drawbacks by providing a non-invasive, fluence-based system and method for crosslinking as a means for bringing collagen or structural proteins of a tissue closer together, effectively reducing volume and "tightening" the tissue.

In accordance with one aspect of the disclosure, a method for tightening or lifting a tissue is provided. The method includes delivering a photochemical agent through a depth of the tissue to distribute the photochemical agent adjacent proteins within the tissue, and irradiating the tissue with an electromagnetic radiation source at a wavelength that activates the photochemical agent, causing a protein response that brings fibers of the tissue closer together in order to one of reduce laxity and tighten the tissue.

In the above method, the delivery step can include puncturing through a surface of the tissue to create access below the surface to the collagen within the tissue and applying a photochemical agent to the surface so that the photochemical agent penetrates the puncture holes and distributes throughout a depth of the tissue adjacent the proteins within the tissue. According to the invention, the delivery step includes inserting a needle into the tissue and simultaneously pulling the needle out of the tissue while injecting the photochemical agent through the needle so that the photochemical agent penetrates a depth of the tissue.

In accordance with another aspect of the disclosure, a kit for treating tissue using with an electromagnetic radiation source is provided. The kit includes a needle sized to create puncture holes in the tissue and a photochemical agent configured to penetrate through the puncture holes when applied to the tissue and to be activated to cause crosslinking of proteins in the tissue when irradiated with a predetermined electromagnetic radiation.

The foregoing and other advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings that form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention.

The disclosure provides a system and method for tightening skin and other tissue through photochemical crosslinking of tissue collagen and other structural proteins. The system includes a mechanism to transdermally deliver a photochemical agent into the target tissue, and an energy source system to uniformly and controllably irradiate the target tissue with electromagnetic radiation. The energy source may include an electromagnetic radiation source that activates the photochemical agent, which causes collagen crosslinking and, in effect, tightens the target tissue. This photochemical tissue tightening system and method can be used instead of surgery to directionally tighten or lift tissue without incurring the risks and side effects associated with existing surgery alternatives.

<FIG> is a schematic view of a tissue tightening system <NUM> according to one aspect of the disclosure. The system <NUM> generally includes a delivery mechanism <NUM>, including a needle <NUM> and/or an applicator <NUM>, and an electromagnetic radiation source <NUM>. The electromagnetic radiation source <NUM> may include a light-emitting system, such as a light emitting diode (LED) or other source configured to effectuate tissue tightening, as will be described. The system <NUM> may be used to photochemically treat (and therefore tighten and/or lift) a target tissue <NUM> such as, but not limited to, skin, epidermis, dermis, fat, fascia, fascial membranes, tendon, epithelium, bladder, bowel, muscle, nervous, circulatory, abdominal, thoracic, colorectal, rectal, intestinal, ovarian, uterine, pericardial, peritoneal, oral, cardiac, and breast tissue, vaginal mucosa, superficial facial layers, superficial muscular aponeurotic system (SMAS), cooper's ligament, orbital septum, and fascia of scarpa. For example, the system <NUM> can be used to accomplish a breast tissue lift, a facial tissue lift, vaginal tightening, post-liposuction skin tightening, post bariatric weight loss surgery skin tightening, or other tissue tightening or lifting applications.

The system <NUM> can be used to tighten the target tissue <NUM> according to the method <NUM> of <FIG>. Generally, the method <NUM> may include a particular photochemical crosslinking (PXL) treatment of punctured target tissue <NUM>. More specifically, the method <NUM> includes delivering a photochemical agent to the target tissue <NUM>, for example, with the delivery mechanism <NUM> at process block <NUM>. More particularly, as will be described, the delivery of the agent at process block <NUM> may include some substeps or may include one or more optional steps.

Once the agent is delivered to the tissue at process block <NUM>, a hold period is observed at process block <NUM>. Following the hold period at process block <NUM>, the target tissue <NUM> is irradiated at process block <NUM>. As one non-limiting example, the irradiation at process block <NUM> may be performed using the electromagnetic radiation source <NUM>. In particular, as will be described, the irradiation at process block <NUM> is specifically performed to activate the photochemical agent delivered at process block <NUM> to cause, at process block <NUM>, collagen crosslinking within the target tissue <NUM>. The crosslinking causes the target tissue <NUM> to tighten or shrink at process block <NUM>.

With respect to process block <NUM>, the photochemical agent is delivered to the target tissue <NUM>. As one example, delivery may be performed using the delivery mechanism <NUM> described above. Generally, a photochemical agent is a chemical compound that produces a chemical effect upon photoactivation or a chemical precursor of a compound that produces a chemical effect upon activation. For example, the photochemical agent may be a photosensitizer or photoactive dye. In one specific application, the photochemical agent can be Rose Bengal. In a further application, the photochemical agent can be <NUM>% Rose Bengal in a saline solution. In other applications, the photochemical agent may be selected from the group consisting of xanthenes, flavins, thiazines, porphyrins, expanded porphyrins, chlorophylls, phenothiazines, cyanines, mono azo dyes, azine mono azo dyes, rhodamine dyes, benzophenoxazine dyes, oxazines, and anthroquinone dyes. In yet other applications, the photochemical agent may selected from the group consisting of Rose Bengal, erythrosine, riboflavin, methylene blue ("MB"), Toluidine Blue, Methyl Red, Janus Green B, Rhodamine B base, Nile Blue A, Nile Red, Celestine Blue, Remazol Brilliant Blue R, riboflavin-<NUM>-phosphate ("R-<NUM>-P"), N-hydroxypyridine-<NUM>-(I H)-thione ("N-HTP") and photoactive derivatives thereof.

The method <NUM> of <FIG> may include any of multiple options for delivering the photochemical agent. According to a first option, the photochemical agent can be applied by first puncturing or piercing a surface of the target tissue <NUM>, for example with a needle <NUM> or an array of needles at process block <NUM>. This initial needle puncturing creates access to tissue below the surface. More specifically, the initial need puncturing creates puncture holes to allow the photochemical agent to be delivered and distributed below a surface of the tissue <NUM> (that is, through the holes to a certain depth of the tissue), allowing collagen and other structural proteins within the tissue <NUM> (such as elastin) to be uniformly exposed to, surrounded by, coated by, in close proximity with, and/or adjacent the photochemical agent. Accordingly, needle puncture holes can be sufficiently spaced apart to puncture a certain percentage of tissue surface area. For example, in some applications, such as skin or epidermis tightening applications, the needle array can be used to puncture approximately less than ten percent or, preferably, five percent of the surface area of the target tissue <NUM>.

Generally, the needle or needles <NUM> can be sized to pierce the tissue but not cause scarring. For example, in some applications, the needle <NUM> can be a hypodermic needle sized between <NUM> gauge and <NUM> gauge. In one specific example, the needle <NUM> can be <NUM> gauge. Coring needles or solid needles are also contemplated in some applications. The needle <NUM> can also be sized to penetrate a partial and/or a full thickness of the target tissue <NUM>. The specific depth of the needle holes can be selected based on the target tissue type and location being treated. For example, hole depths of about <NUM> millimeters to <NUM> millimeters can be used in skin tissue, where such depths correspond approximately to the thickness of the dermis layer.

Regarding needle arrays, both needle size and spacing can be configured to ensure proper distribution of the photochemical agent to a desired percentage of the tissue volume, without causing scarring. <FIG> shows a needle array <NUM> according to the invention. The needle array <NUM> includes a handle <NUM>, a head <NUM>, and a button <NUM>. The handle <NUM> can be sized to permit a user to grip the handle <NUM>. The head <NUM> can be integral with or coupled to an end of the handle <NUM> and includes retractable needles (not shown) configured to extend from a surface of the head <NUM> at an approximate <NUM>-degree angle relative to the handle <NUM>. The button <NUM> can be pushed or depressed to extend the retractable needles out from the head <NUM>, and the needles can then again retract into the head <NUM> once a user stops depressing the button <NUM>. The needles in the array <NUM> can have sizes similar to the hypodermic needles (or other needles) described above. In one application, the needle array <NUM> can include a set of hypodermic needle tips spaced approximately one millimeter apart in all directions. Other needle array configurations, besides what is shown in <FIG>, is also contemplated in some applications. More specifically, the needle array <NUM> can be configured in any of a variety of spatial distributions depending on the tissue <NUM> being treated. For example, the needle array <NUM> can include multiple needles arranged as one or more rows, a regular two-dimensional pattern (such as a square, rectangular, or triangular pattern), a random distribution, or the like. Array configurations may also be sized and arranged based on desired direction of tissue lifting or tightening. Additionally, needle rollers or tattoo guns may be used in some implementations to puncture the target tissue <NUM>.

Once the target tissue <NUM> is punctured, the photochemical agent is applied to a surface of the target tissue <NUM>, for example using the applicator <NUM> at process block <NUM>. The amount of photochemical agent applied to the target tissue <NUM> can depend on the type of target tissue <NUM> and, more specifically, the amount of collagen and other structure proteins in the target tissue <NUM>. This application step can include, but is not limited to, staining, painting, brushing, spraying, dripping, or otherwise applying the photochemical agent to the target tissue <NUM>. Example applicators <NUM> include, but are not limited to, sponges, brushes, and cotton tip applicators. According to another example, the applicator <NUM> can be a material, such as a bandage, with the photochemical agent soaked in, coated, or otherwise applied, so that the applicator <NUM> can be placed on the tissue <NUM> to transfer the photochemical agent to the tissue <NUM>. Once the photochemical agent is applied to the target tissue <NUM> using one of the above-described methods, excess photochemical agent on the tissue surface may also be removed, for example by dabbing with gauze or another material.

According to a second application option, process blocks <NUM> and <NUM> can be consolidated or supplemented by directly injecting the photochemical agent into the tissue at process block <NUM>. More specifically, according to the invention, a needle or needle array <NUM> can be inserted into the target tissue <NUM> and slowly drawn back out while simultaneously injecting the photochemical agent. By injecting the photochemical agent as the needle <NUM> is drawn out, collagen and other proteins in the target tissue <NUM> can be sufficiently surrounded by or in close proximity to the agent.

According to a third application option (not shown), the photochemical agent may be applied to a surface of the target tissue <NUM>, and then the surface can be punctured with a tattoo gun to transfer the photochemical agent throughout a depth of the tissue <NUM> adjacent the proteins.

Following agent application, with respect to process block <NUM>, a hold period can provide time for the photochemical agent to penetrate a depth of the target tissue <NUM> through the puncture holes in the target tissue <NUM> and surround, or be in very close proximity or adjacent to, the collagen. In some applications, the hold period can be about thirty seconds to about five minutes. In one specific application, the hold period is about one minute. An optimal hold period can be determined by experimental testing for specific target tissues and/or specific photochemical agents. For example, Rose Bengal has a high affinity for collagen and a relatively limited penetrance, thus requiring a minimal hold period.

With respect to process block <NUM>, the target tissue <NUM> is irradiated, for example using the electromagnetic radiation source <NUM>. The electromagnetic radiation source <NUM> can emit light at an appropriate energy, wavelength, and duration to cause photochemical agent activation. For example, the electromagnetic radiation source <NUM> can be configured to irradiate the target tissue at an irradiance of less than about one watt per centimeter squared (W/cm<NUM>). In other applications, however, light can be delivered at an irradiance between about <NUM> W/cm<NUM> to about five W/cm<NUM>, preferably between about one W/cm<NUM> and about three W/cm<NUM>. Also, the electromagnetic radiation source <NUM> can be a low-energy visible-light emitter, for example, configured to emit monochromatic or polychromatic light. Suitable electromagnetic radiation source examples include, but are not limited to, commercially available lasers, lamps, one or more light-emitting diodes ("LEDs"), or other sources of electromagnetic radiation. In one specific example, the electromagnetic radiation source <NUM> can be a multi-light-emitting LED array <NUM>, as shown in <FIG>. More specifically, the LED array <NUM> can be a high-powered (<NUM> milliwatt) LED array.

Furthermore, the electromagnetic radiation source <NUM> can emit light at an appropriate wavelength that activates the type of photochemical agent used. More specifically, the wavelength of light can be chosen so that it corresponds to or encompasses the absorption of the photochemical agent, and reaches a desired volume of tissue <NUM> that has been contacted with the photochemical agent (that is, penetrates a desired depth of the tissue <NUM>). For example, when Rose Bengal is the photochemical agent used, the electromagnetic radiation source <NUM> can be a low-energy, green-light emitter. For other photochemical agents, the wavelength used can range from about <NUM> nanometers to about <NUM> nanometers, preferably between about <NUM> nanometers to about <NUM> nanometers.

Also, the electromagnetic radiation source <NUM> can emit light at the target tissue <NUM> for an appropriate duration based on the photochemical agent and tissue type. In some applications, the target tissue <NUM> is irradiated for a duration of about one minute to about thirty minutes. In other applications, the target tissue <NUM> is irradiated for a duration of less than about five minutes.

Moving on to process block <NUM>, irradiating the target tissue <NUM> with the electromagnetic radiation source <NUM> activates the photochemical agent, causing collagen crosslinking. More specifically, when distributed adjacent to collagen, the photochemical agent binds to the collagen in a noncovalent manner. The illumination then activates the photochemical agent to induce collagen crosslinking through covalent bonding. Furthermore, while other structural proteins like elastin may not have the same physical interaction with the photochemical agent as collagen, the other proteins may still experience the same protein response to the illumination as collagen.

At process block <NUM>, the effect of crosslinking is that the target tissue <NUM> is tightened (that is, the tissue volume is reduced). In other words, the activated photochemical agent causes a protein response that brings fibers of the tissue closer together in order to tighten the tissue or reduce tissue laxity. For example, target skin tissue <NUM> treated using the above method <NUM> becomes stronger and more resistant to degradation typically seen with aging. Specifically, the collagen crosslinking inhibits the ability of matrix metalloproteinase ("MPPs," also known as fibroblast collagenase) to breakdown collagen, slowing the aging process and the appearance of cellulite. In other words, the collagen cross-linking tightens the skin, hiding the appearance of cellulite and protecting against dermal thinning-one of the major causes of cellulite. In another example, in the case of target face or breast tissue <NUM>, tightening the tissue <NUM> via the above method can lift the tissue <NUM> (therefore providing a face lift or a breast lift).

In addition to the above-described method, other methods may be used to transdermally deliver the photochemical agent to the target tissue <NUM> in some implementations. For example, a separate electromagnetic radiation source, such as a laser, can be used to create the holes (that is, rather than the needle <NUM>). In another example, when the target tissue <NUM> is skin, the stratum cornea (that is, the outermost layer of the epidermis) can be removed by tape, Jessner's solution, Trichloroacetic Acid, or another chemical agent or solution. In other words, the surface of the target tissue <NUM> can be "punctured" by removing its outermost layer. Following this removal step, the photochemical agent can be applied to the tissue <NUM>, as described above. Additionally, liposomes or other nano-carriers may be used to deliver the photochemical agent so that it surrounds the target tissue <NUM>. For example, a nano-carrier with the photochemical agent can be delivered to the surface of the target tissue <NUM> so that the nano-carrier penetrates the target tissue <NUM> to distribute the photochemical agent adjacent the proteins within the tissue <NUM>. Other nanotechnology techniques may also be used.

Because of the needling step (process block <NUM>) and/or the injection step (process block <NUM>), a depth of the tissue <NUM>-rather than just the tissue surface-can receive the photochemical agent subjected to irradiation. In some applications, only applying a photochemical agent to the tissue surface does not allow collagen to be coated by the agent or sufficiently irradiated to activate collagen crosslinking. For example, certain photochemical agents have limited penetration through the superficial skin barrier and cannot reach into the tissue to allow for collagen crosslinking. As a result, such photochemical agents are not effective without intentionally creating holes in the tissue <NUM> (via process blocks <NUM> or <NUM>) to receive the photochemical agent.

Thus, unlike previous photochemical treatment therapies, which serve to close tissue holes or wounds, the present method <NUM> intentionally creates holes in the tissue <NUM> in order to tighten it. In particular, unlike previous therapies, the present photochemical crosslinking method <NUM> applies a photochemical agent and light to a tissue <NUM> to crosslink proteins to bring structural fibers closer together to reduce the tissue volume and therefore tighten it. For example, photochemical tissue bonding involves crosslinking between two tissue surfaces to bond the separate tissue surfaces together, and photochemical tissue passivation involves crosslinking a single tissue surface to modify a biological response (such as to strengthen or stiffen the tissue). Unlike photochemical bonding or tissue passivation, which treat two tissues and a tissue surface, respectively, the present photochemical crosslinking method is used to treat a volume of tissue (that is, from the tissue surface through a depth of the tissue) to tighten the tissue and reduce laxity. In other words, the other methods do not cause the same response as the present method, that is, bonding or strengthening tissues using the other methods does not cause a reduction in tissue volume or laxity.

By way of example, the above-described system <NUM> and method <NUM> were experimentally used for photochemically tightening human skin of five patients (discarded from elective abdominoplasty operations). Of the twenty-six sample sites treated, on average, the total surface area of treated samples decreased by <NUM>% (p<<NUM>). For example, <FIG> illustrates a comparison between a sample before treatment <NUM>, including reference markers <NUM>, and after treatment <NUM>, including reference markers <NUM>. As shown in <FIG>, the reference markers <NUM> of the post-treatment sample <NUM> are closer together than the reference markers <NUM> of the pre-treatment sample <NUM>, illustrating a decrease in tissue surface area caused by the treatment.

Additionally, mechanical testing was performed on sample sites using a tensiometer to measure elastic modulus before and after treatment. The elastic modulus and peak load were recorded on samples that were (<NUM>) untreated (<NUM>) partially treated (needled only), and (<NUM>) fully treated (needled plus agent application and irradiation). Full treatment included full thickness needling of the skin surface followed by application of a <NUM>% solution of Rose Bengal in saline and irradiation with a multi-light-emitting LED diode array that delivered green light to the sample surface. In comparing the three test groups, there was no statistically significant difference between untreated skin and needled skin; however, there was a statistical difference between those two groups and photochemically-treated samples, with the latter exhibiting a five-fold increase in the elastic modulus and a three-fold increase in peak load.

Furthermore, a biodegradation assay was performed to assess the efficacy of the above method <NUM> to inhibit collagenase breakdown of collagen (collagenase is an enzyme that breaks down, or digests, collagen). The assay was performed to compare an untreated (control) group and a treated group. For the control group, the digestion time was <NUM> minutes. For the treated group, the digestion time was <NUM> minutes. This represents a <NUM>-fold increase in the time needed for digestion, thus showing that the treatment (using the above method <NUM>) does, in fact, inhibit collagen biodegradation due to crosslinking.

Accordingly, the system <NUM> and the method <NUM> can decrease tissue surface area, increase elastic modulus, increase peak load, and/or increase collagenase digestion time. For example, compared to untreated tissue, the system <NUM> and method <NUM> can decrease tissue surface area by between about <NUM>% to about <NUM>%, preferably between about <NUM>% to about <NUM>%; can increase elastic modulus between about two-fold to about twenty-fold, preferably between about four-fold to about ten-fold; can increase peak load between about two-fold to about ten-fold, preferably between about two-fold to about five-fold; and can increase collagenase digestion time between about two-fold to about ten-fold, preferably between about two-fold to about five-fold. Other ranges of decreased surface area and increase elastic module, peak load, and/or digestion time are also contemplated.

In light of these advantages, the system <NUM> and method <NUM> can be used in applications such as those related to reducing skin laxity; body contouring; skin tightening of aged, post-surgical, or post-liposuction skin; non-surgical breast lifts or face lifts; vaginal tightening; reducing the appearance of cellulite or striae (that is, stretch marks); or tightening tissues like lose tendons. Other applications are also contemplated.

When used for such applications, the above system <NUM> and method <NUM> provide a minimally invasive treatment. Thus, the system <NUM> and method <NUM> provide a safer, less risky, and more efficient way to tighten tissue compared to surgery. The method <NUM> also provides for shorter recovery times and fewer complications than other aesthetic treatments, such as Thermage® (a radiofrequency energy treatment), Ultherapy® (an ultrasound energy treatment), fractional ablative lasers (a treatment that removes a layer of tissue), and coring needles (a treatment that punctures tissue to remove small tissue biopsies).

More specifically, compared to other energy-based treatments, the method <NUM> is fluence dependent. The method <NUM> is therefore a safer, more forgiving, and a less painful alternative to power-dependent systems, such as ablative lasers. Also, the present method <NUM> does not cause a substantial temperature increase in the tissue <NUM> compared to other energy-based treatments. For example, ultrasound- and radiofrequency-based methods do not cause crosslinking, but rather thermally injure tissue to induce tissue remodeling and contracture. Unlike those thermal methods, the present method <NUM> does not heat the tissue <NUM> enough to cause damage, and therefore preserves the tissue's structural integrity by preventing cell toxicity and avoiding protein denaturation due to tissue heating.

Additionally, the photochemical skin tightening system <NUM> and method <NUM> has been shown to deliver consistent, natural-looking results with long-lasting effects. In particular, the system <NUM> and method <NUM> have been shown to be more consistent than other surgery alternatives, and have shown similar, consistent results for all types of tissue treated. Furthermore, the results are more natural-looking because the system <NUM> and method <NUM> do not leave any scars (e.g., due to surgical cutting or thermal damage).

The system <NUM> and method <NUM> may also be more affordable than current treatments. In particular, because the system <NUM> and method <NUM> are a surgery alternative, treatment can be performed by, for example, a nurse practitioner in a clinic or physician's office rather than a surgeon in an operating room. And the system <NUM> and method <NUM> do not require costly capital equipment, like the laser-emitters required for other surgery alternatives, but still produce a high-margin consumable. For example, the system <NUM> and, in particular, the electromagnetic radiation source <NUM> may be cheaper than and occupy a smaller footprint than traditional ablative lasers.

In some applications, the electromagnetic radiation source <NUM> (such as a laser) can be easily stored in a clinical setting, and a photochemical treatment kit <NUM>, as shown in <FIG>, can be provided for use with the electromagnetic radiation source <NUM>. The kit <NUM> can include an agent <NUM> and a needle device <NUM> (such as a single hypodermic, solid, or coring needle <NUM> or a needle array <NUM>). Alternatively, the kit <NUM> can include an agent <NUM> and a disposable head <NUM> (as shown in <FIG>) for use with a reusable handle <NUM>, which can be stored in a clinic setting. In yet other applications, the kit <NUM> can further include one or more applicators. Also, the kit <NUM> can be scalable for different treatment areas or tissues. For example, the amount of agent <NUM> and the size of the needle device <NUM> in each kit <NUM> can be specific to a treatment area or tissue.

Claim 1:
A kit (<NUM>) for treating tissue and for use with an electromagnetic radiation source (<NUM>, <NUM>), the kit (<NUM>) comprising:
a needle (<NUM>) configured to create puncture holes in the tissue; and
a photochemical agent (<NUM>) configured to penetrate through the puncture holes when applied to the tissue and to be activated to cause crosslinking of proteins in the tissue when irradiated with a predetermined electromagnetic radiation;
wherein:
(a) the kit (<NUM>) comprises the needle (<NUM>), which is part of a needle array (<NUM>) of the kit (<NUM>) and the needle array comprises a handle (<NUM>), a head (<NUM>) and a button (<NUM>), the head (<NUM>) including retractable needles configured to extend from a surface of the head (<NUM>) by depressing the button (<NUM>) and retract into the head (<NUM>) once a user stops depressing the button (<NUM>), the head (<NUM>) configured to be coupled to the handle (<NUM>); and
(b) the kit (<NUM>) is configured to allow insertion of the needle (<NUM>) of the kit (<NUM>) into the tissue; and wherein the kit (<NUM>) is configured to allow for simultaneously drawing back the needle (<NUM>) out of the tissue while injecting the photochemical agent (<NUM>) through the needle (<NUM>) so that the photochemical agent (<NUM>) penetrates a depth of the tissue.