KR20020088832A - Therapeutic light source and method using the same - Google Patents

Abstract

PURPOSE: Provided is a light source having a fluorescent tube used for treatment such as photodynamic therapy(PDT) and for diagnosis and a method for treatment and diagnosis using the same. CONSTITUTION: The light source is of a fluorescent tube type and includes a non-flat array of a substantially linear discharge tube aligned to emit lights substantially in the visible light spectrum range at a intensity of 3 mW/cm¬2 or more to a patient. The tube emits lights in the substantially limited range of 350 to 500 nm. The tube is aligned along a plane bending perpendicular to the longitudinal direction of the tube and mounted on a inner curved surface of a housing disposed to cover at least a part of the body of a patient. The housing moves over the body of the patient.

Description

Therapeutic light source and method using the same

FIELD OF THE INVENTION The present invention relates to non-interfering light sources used in the treatment of photodynamic therapy (PDT) and the like, and more particularly (but not exclusively) to light sources and / or to treat a wide range of external surfaces of patients. It is about how to use.

Photodynamic therapy involves administering a photosensitive agent to the site of infection and then irradiating with light—for example, 'The Physics of Photodynamic Therapy' in Medicine & Biology 31 (1986) by BC Wilson and MS Patterson. See April No. 4, London GB.

WO 97/40888 proposes the use of one or more fluorescent tubes emitting yellow, orange and / or red wavelengths in a lamp for PDT. However, because the absorption coefficients of the various PDT drugs and human tissues used in PDT are quite low in this wavelength region, the light has a high transmission depth and therefore is not suitable for the treatment of external diseases. Moreover, the treatment time is long because the activity efficiency of most PDT drugs is low at these wavelengths and the light obtained in the fluorescent tubes is also relatively low.

International patent WO 99/56827 discloses a light source for treating or diagnosing PDT of the head or face, preferably comprising a U-shaped fluorescent tube emitting blue light. This light source has a problem that the manufacturing cost is expensive because the U-shaped tube has to be specially manufactured for such an application.

Accordingly, the present invention is to provide a light source of a fluorescent tube used in the treatment of photodynamic therapy (PDT, etc.) and a method of using the same.

1 is a schematic circuit diagram of a fluorescent tube array in an embodiment according to the present invention.

2 is a front view of the tube array in the housing.

3 is a cross-sectional view along the A-A plane perpendicular to FIG. 2.

4 is a profile of the light intensity of the tube array across the treatment site.

Figure 5 shows the absorption spectrum of PpIX, the emission spectrum of the lamp according to the prior art and the emission spectrum of the fluorescent tube of the tube array.

6A and 6B are schematic diagrams in the longitudinal and transverse directions of a lamp using medium / high pressure discharge tubes for totally treating one side of a patient, respectively.

7A and 7B are schematic diagrams in the longitudinal and transverse directions of a lamp using a straight fluorescent tube for the treatment of a portion of a patient, respectively.

8A and 8B show the variant arrangement of FIGS. 7A and 7B for the treatment of the entire body of the patient.

9A and 9B show schematic diagrams when the door is open for access and during use of a lamp using a fluorescent tube to treat the lower half of the patient's body.

10A and 10B are front and side schematic views of a lamp using fluorescent tubes arranged on the reflective inner surface of the booth, respectively, which can enter the awning.

11A and 11B are front and side schematic views of a lamp using medium / high pressure discharge tubes, respectively, for treatment of one side of a patient while standing.

12A and 12B are front and side schematic diagrams of grid lamps positioned at the portions to which light of a patient to be treated is irradiated, respectively.

13A and 13B are front and side schematic views of a lamp including four substantially coplanar grid lamps arranged in a row, for irradiating all of the patient's body, respectively.

14 is a perspective view of a lamp mounted on a bed and using medium / high pressure discharge tubes for facial treatment.

FIG. 15 is a perspective view of a free-standing variant of the arrangement of FIG. 14.

16-18 are side and partial cross-sectional views of a lamp that includes an array of parallel fluorescent discharge tubes for treatment of the foot, lower leg and the entire leg, respectively.

19A-19C are cross-sectional views, plan views, and vertical cross-sectional views perpendicular to the face of the arm for lamps using medium / high pressure tubes for the elbow treatment of a patient, respectively.

20A and 20B are top and side views, respectively, of a lamp comprising a medium / high pressure discharge tube for the treatment of the patient's face and / or head in a sitting position.

FIG. 21 is a perspective view of a lamp mounted on a bed for the treatment of a lying patient and similar to FIGS. 20A and 20B.

In order to achieve the above technical problem, the present invention provides a light source for treatment and / or diagnosis and a treatment method using the same.

According to one aspect of the invention, there is provided a therapeutic light source comprising a non-interfering array of substantially straight fluorescent tubes arranged to emit light in a substantially visible light spectral region.

In one embodiment of the invention, the array may be mounted on a curved surface perpendicular to the longitudinal direction of the tube.

In another embodiment of the invention, the array may be mounted on at least two planes arranged to be angled to each other.

According to yet another aspect of the present invention, there is provided a therapeutic light source comprising one or more fluorescent grid lamps each comprising a tube having a plurality of folds in the same plane.

According to another aspect of the invention, there is provided a therapeutic light source comprising a discharge tube and a concave reflector arranged to focus light on the treatment site. In one embodiment, the light source is mounted in a housing having an opening for positioning a part of the patient's body therein.

According to another aspect of the present invention, by directly emitting a narrow band butterfly light to reach the patient at an intensity of 3 mW / cm ² , preferably 10 to 100 mW / cm ² (not exceeding about 200 mW / cm ² ) A light source for PDT is provided that includes one or more medium / high voltage discharge lamps arranged. Such medium / high pressure discharge lamps can provide greater intensity than low pressure fluorescent lamps and still provide the advantages of narrow band butterflies over large areas, without intermediate optics.

Preferably, the band width of the medium / high voltage discharge lamp is 160 nm or less.

Preferably, the arc length of the medium / high voltage discharge lamp is at least 15 mm.

The or each medium / high pressure discharge lamp may be straight, fold or tortuous.

In any aspect of the invention, the one or more lamps are preferably arranged in a housing having a window or opening (where light reaches the patient), the reflector reflecting light from the lamp like a mirror through the window or opening. It is preferably arranged to reflect or diffuse to reflect. The reflector is preferably arranged to give a uniform output.

The present invention includes a method of using a light source for PDT, wherein a topical photosensitive agent such as 5-aminoabulinic acid (5-ALA) is applied to an infected site of a patient and then irradiated with light from the light source . The method is preferably used to treat external tumorous or non-tumoral diseases. Preferably the method comprises actinic / sun keratose, Bowen disease, shallow basal cell carcinoma, basal carcinoma, epithelial carcinoma, fungal sarcoma, T-cell lymphoma, acne and sebaceous gland, psoriasis, eczema, seborrhea It is used for the treatment of one or more of nevus, viral infections such as herpes simplex, infectious continuous species, and warts (refractory warts, vulgar warts or plantar warts), alopecia areata, or hirsutism. The total treatment time is preferably no longer than 1 hour per time.

The present invention uses a photosensitive drug for removing burgundy birthmarks and hair restoration / removal, as well as a treatment method for beauty or partial beauty without using photosensitive drugs for skin regeneration, wrinkle removal or biostimulation (including wound care). It includes more.

In the embodiment shown in FIGS. 1-3, six similar fluorescent tubes 2 are mounted in parallel in an array in hollow housings made of polished stainless steel and generally cubic. The tube 2 is thereby electrically connected to an electronic ballast 6 for initiating and maintaining the flow of current. The ballast 6 is powered by an alternating current main power supply 8. The fan 10 is also driven by the main power supply 8 and draws air through a vent opening (not shown) in the housing 4 to cool the tube 2.

The individual tubes are firmly located in the elastic sheath bracket 12 at the respective ends attached to the rear wall 14 of the housing 4. The inner surface of the back wall 14 is a white diffuse reflector 16 arranged to diffuse and reflect toward the front of the light emitted by the tube 2. The diffuse reflector 16 may be made of a white self-adhesive plastic sheet (such as Fablon ^™ ) or a removable paper sheet or other material that can be easily replaced when dirty. Instead of diffuse reflectors, non-planar mirror reflectors, such as concave metal reflectors often used in high power security lamps, may be used to provide uniform light rays.

The housing 4 has an opening 18 on its front surface that is substantially sized and shaped with the light emitting portion of the array of tubes 2. The opening 18 is covered with a transparent or translucent cover 20, for example a plastic such as pure polycarbonate (eg Makrolon ^™ ). The cover 20, when positioned, protects the internal components and the patient. Preferably, the housing 4 is positioned horizontally upwardly with the opening 18, and the patient lies on the cover 20 or places an infection site, which covers the patient or site of infection. Robust enough

The cover 20 may filter the light emitted by the tube 2 before reaching the patient. For example, the lid 20 may comprise a layer of material that filters out a portion of the emission spectrum of the tube 2. The material may filter the visible spectrum that does not activate UV radiation and / or related photosensitive agents. The material layer may be removably attached to the support forming portion of the lid 20, such as a guide rail, to completely exchange or remove this filter layer with another filter layer.

In one embodiment, the length a of the housing 4 is 600 mm, the width b is 300 mm and the depth c is 70 mm.

The arrangement of the diffuse reflector 16 and the tube 2 results in the ray profile shown in FIG. 4. In this embodiment, the tube is 38 mm in diameter and is 15 mm apart from the adjacent tube. Over the width of the treatment site (in the direction of the width b of the housing 4) extending at least about 30 cm, the light intensity only changes by about 6%. The uniformity minimizes the risk of some areas on the skin of patients receiving less light than the threshold amount of light, which is important to prevent the recurrence of the disease to be treated.

The tube 2 has a fluorescent coating that is selected to emit light with a narrow spectrum that matches the absorption peak of the photosensitive drug and is substantially defined within 350 to 500 nm, most preferably 400 to 450 nm. 5 shows the output spectrum of a suitable fluorescent tube, reference TL / 03, such as Philips part number TLK 40/03, which is commercially available and used for diazo printing. The spectrum shows a very narrow, low energy peak, further at 435 nm and 546 nm with a main peak of 420 nm.

The absorption spectra of PpIX are superimposed on the graph but shown in relative units of light density shown on the left side of the graph. It can be seen that the absorption peak at 410 nm is larger and wider than the absorption peak at 633 nm or other peaks at 545 nm and 580 nm, which is consistent with the output of the lamp disclosed in WO97 / 40888. Thus, for the same skin area where the precursors of 5-ALA, PpIX are applied topically, the light from the lamps of the above examples has substantially shorter transmission depths and about 20 times greater activity efficiency. In the treatment of external diseases of the skin by PDT, the number of treatments is shorter because the underlying layer of the skin is substantially free of damage and is absorbed more efficiently by the infected tissue.

Actinic / sun rays keratose, Bowen's disease, shallow basal cell carcinoma, basal carcinoma, epithelial carcinoma, fungal sarcoma, T-cell lymphoma, acne and sebaceous gland, psoriasis, eczema, seborrheic nevus, herpes simplex Methods of treatment of external diseases such as viral infections, infectious continuous species, and warts (refractory warts, vulgar warts or plantar warts), alopecia areata, or hirsutism are described below. A cream or solution containing a photosensitive agent, such as 5-ALA, is applied topically, intravenously or orally, to a site of infection in the patient's skin as directed by a physician. In another method of application to a wide range of sites, the patient's body is submerged in a solution bath. The infected site is then covered for 3-6 hours or up to 24 hours if treatment should continue until the next day to prevent the removal of drugs and carriers or activation by sunlight. The covering of the site is peeled off and exposed to light from the lamp according to the first embodiment for 15 to 30 minutes. The treatment can be repeated one to three or more times if necessary, depending on the severity or form of the disease. This method is particularly suitable for the treatment of patients with very large or complex lesions that spread over a wide range of sites.

The lamp can also be used for fluorescence detection (photodiagnosis).

The lamps can be used in combination with photosensitive drugs for removing burgundy birthmarks and hair restoration / removal, as well as without using photosensitive drugs for skin regeneration, wrinkle removal or biostimulation (including wound care). It can also be used as a treatment.

The ramp can be sized such that an effective treatment area (eg, as defined as a substantially uniform degree of illuminance as shown in FIG. 4) develops throughout the patient's entire body or just that area to be treated. The systemic size is particularly suitable for sebaceous seizures, myxosarcoma and precancerous skin diseases.

The lamp may include an electro-optical detector arranged to measure the amount of light transmitted and to turn off the light emission when the target amount is reached. Alternatively or alternatively, the detector measures the instantaneous light intensity, changes the power supplied to the tube to maintain the intensity within a predetermined limit, and / or the light if the maximum limit is exceeded. Arranged to turn off the discharge.

In an alternative embodiment, TL / 52 fluorescent tubes with peak emission at about 450 nm are used in place of TL / 03 tubes. However, the TL / 52 tube is less desirable because of the low absorption of PpIX near this wavelength.

In another alternative embodiment, a low pressure 'grid lamp' may be used that includes a low pressure mercury or xenon arc lamp. Such 'grid lamps' are made of narrow aperture silica or glass tubes, and have an outer diameter of about 13 mm or less, preferably 9 mm or less, and they are stacked in a serpentine form so that the overall arc length is between several centimeters and 10 meters. Lost Preferably the tube is made of quartz that passes UV light. The phosphor is coated on the diameter of the outer or second outer concentric tube of the tube.

In certain embodiments using fluorescent tubes, at least 70% of the entire perimeter of the individual tubes are coated with phosphor. In the case where only a portion of the surroundings is coated with a phosphor, the remainder may be coated with a reflective material to reflect discharge radiation to the phosphor coated portion of the tube. These tubes are mounted to concentrate light on the patient.

The phosphor provides an emission wavelength that substantially matches the photosensitizer absorption spectrum, as shown in Table 1 below.

Photosensitizer absorption spectrum Photosensitizer Red absorption band (nm) Red Peak (nm) Blue / Green Peak (nm) Naphthalocyanine 780-810 Chalcogenopylium Dyes 780-820 Phthalocyanine (such as ZnII Pc) 670-720 690 Tin Ethiofurfurin (SnET ₂ ) 660-710 660-665 447 Chlorine (eg, N-aspartyl chlorine e6 or NPe6) 660-700 664 Benzoporphyrin Derivatives (BPD) 685/690 456 Ruthenium Nexaprin (Lu-Tex) 735 Al (S ₁ / S ₂ / S ₃ / S ₄ ) Pc 660-710 670/685 410, 480 Porphyrin 625/630 405 From Protoporphyrin IX (PpIX) -5δ aminoabuline acid (5ALA) 635 410, 505, 540,580 Tetra m-hydroxyphenyl chlorine (mTHPC) 650 440, 525

Two or more phosphors in the coating can be mixed to provide the required emission spectrum. Other phosphor coatings available from BHK, Inc., USA have the properties shown in Table 2 below.

BHK Phosphor Peak Emission and Bandwidth Peak emission wavelength (nm) Band Butterfly (nm) 406 41 418 29 430 114 460 105 494 170

Alternative phosphor coatings available from Jelight Company, Inc., Irvine, CA, USA have the properties shown in Table 3 below.

Jelight phosphor peak emission and band butterflies Peak emission wavelength (nm) Band Butterfly (nm) 400 37 413 34 420 34 446 112 446, 525, 580 Discrete peak 447 32 450 49 455 62 460 105 473 136 479 75 482 138 495 223

In another alternative embodiment, medium / high pressure discharge tubes are used in place of the low pressure fluorescent tubes 2, and the drive current is thus replaced. Medium / high pressure discharge tubes generally provide higher intensity outputs than fluorescent tubes, with the electrons separated at wider intervals and having individual reflectors arranged to provide uniform illuminance. The medium / high pressure discharge tube has a gaseous charge selected to activate the photosensitizer in use, an example of which is shown in Table 1 above. Sample gas and vapor charges are shown below in FIG. 4.

shape Filling Emission Wavelength ^* (nm) Medium Pressure Mercury + Additives gallium 400-430 thallium 530-550 cadmium 440, 550, 580 Gallium + thallium 400-420, 440, 450, 540 indium 450-460 Gallium + Lead 400-460 High pressure Sodium gas 560-640 Sodium gas + xenon or mercury 600-760 Medium pressure inert gas neon 585-670 argon 416-488, 697 krypton 427-587 Medium pressure steam cadmium 480, 508 Mercury 405, 436, 546, 577 cesium 455, 852 zinc 636 thallium 535 potassium 766

* Discontinuous peaks, represented by a single peak wavelength, continuous emission bands

Another possible charge is mercury-argon or mercury-xenon at medium or high pressure, which causes the two emission spectra to overlap the pressure-width varying continuum together across the line of sight spectrum.

In an alternative embodiment, an array of high pressure metal halide lamps may be used where arcs are burned in dense mercury vapor and rare earth halides, resulting in peak emission of 400-650 nm.

A possible alternative arrangement of the tubes in this embodiment is described below. In these individual arrangements, straight tubes or grid lamp tubes are used because these forms are commercially available at low prices. Where fluorescent tubes, grid lamp tubes or medium / high pressure discharge tubes are described, they can be any tube of the type described above. In such an arrangement, the fluorescent tubes provide a medium / high pressure discharge tube by increasing the spacing between the tubes and by providing separate shaped reflectors for the individual tubes, except where such separate reflectors are impractical due to limitations in shape and size. Can be replaced with Similarly, medium / high pressure discharge tubes can be replaced with fluorescent tubes except where the light intensity is too low for practical phototherapy or diagnostic use.

6A and 6B show lamps using medium / high pressure discharge tubes 2 'for systemic treatment of one side of patient P. FIG. The lamp comprises three such tubes arranged parallel to each other and perpendicular to the longitudinal direction of the patient in the housing 4. Each tube has a curved reflector 16 arranged behind it to produce approximately uniform illuminance to the patient lying on the surface S.

7A and 7B show lamps that use straight fluorescent discharge tubes 2 to treat the site of patient P. FIG. The tubes are arranged parallel to one another and arranged in the longitudinal direction of the patient, the interior of the curved housing 4 which is movable relative to the patient P along the longitudinal direction of the patient to irradiate the desired area of the patient P. Arranged on the reflective surface 16. The surface S that the patient can lie down to may be a cover 20 of a flat lamp using the fluorescent tube 2 as described above. 8A and 8B show a modified form in which the tube 2 and the housing 4 substantially cover the entire body of the patient P for systemic treatment. In this case, the housing 4 need not be movable.

9A and 9B show lamps using fluorescent tubes 2 for the treatment of the lower half of the patient's body. The tube is arranged on the internal reflective surface of the housing 4, in which the patient stands. The housing 4 is cylindrical with a slightly tapered end of the diameter and the diameter increases along the height to keep the distance between the patient's skin and the tube 2 'approximately constant. The housing 4 may have an inlet that is open for entry as shown in FIG. 9B.

10a and 10b show a lamp using a fluorescent tube 2 arranged on a reflective inner surface of a booth-shaped housing 4 that can enter the vessel, the housing having an elliptical constant diameter in height, The circle, rectangle, hexagon or cross section may be polygonal. The booth includes a door, and the inner surface of the door is equipped with a portion of the tube. The tube extends in a substantially vertical direction.

11A and 11B show lamps using medium / high pressure discharge tubes for treatment of one side of a patient. This arrangement is similar to that shown in FIGS. 6A and 6B except that four parallel tubes are used and the lamp is standing upright to irradiate light on one side of the patient P.

Figures 12A and 12B show grid lamps 2 "mounted for irradiating the site of a patient being treated in an embodiment of the present invention. Figures 13A and 13B are arranged in a line, to irradiate the entire body of the patient Another lamp comprising four such substantially coplanar grid lamps 2 ".

14 and 15 show lamps using medium / high pressure discharge tubes according to any of the above embodiments. In Figure 14, the lamp is mounted on either end of the bed (S) and is adapted to adjust its height over the bed for facial treatment of the patient lying on the bed. In FIG. 15, the lamp is mounted on a stand ST and is height adjustable to treat selected areas of the patient P lying on the bed S. In FIG.

16-18 show lamps comprising an array of parallel fluorescent discharge tubes, for the treatment of sedentary patients P. FIG. The arrangement of FIG. 16 is used to treat a patient's foot.

The arrangement of FIG. 17 is used to treat the lower leg of the patient. The arrangement of FIG. 18 includes two flat arrays of these tubes arranged at the bottom and inner back of a desk-like structure (D) to treat the entire patient's leg. The desk-like structure (D) is desirable for long time treatments because it allows the patient to sit comfortably at the desk head for reading, eating or other activities.

19A-19C show lamps using medium / high pressure discharge tubes 2 ″ for elbow treatment of a patient. The lamps have a cubic housing 4 with two similar openings 22 on one side. And the opening allows an elbow to enter the housing 4. A medium / high pressure discharge tube 2 'is mounted with a reflector towards the bottom of the housing. Is concentrated on the elbow of the patient P by the reflector.

20A and 20B show lamps comprising medium / high pressure discharge tubes for the treatment of the face and / or head. The lamp has a front face portion 24 including a medium / high pressure discharge tube 2 'and a reflector 16 for direct irradiation of light directly to the face of the patient P. The head 26 and the left and right face parts 28a and 28b are attached to the front face part 24 by a hinge, each of which has a medium / high pressure discharge tube 2 'and a light head, left and right faces, respectively. And a reflector 16 to direct. The front face part 24 is preferably attached to the stand ST so that it can move vertically to fit the head height of the patient P when the patient is sitting.

FIG. 21 shows a lamp similar to the arrangement of FIGS. 20A and 20B except that it is arranged for the treatment of the face and / or head of a lying patient. The vertical support is mounted on the bed S instead of upright and the lamp can rotate 90 ° to fit the head position when the patient is lying down.

The above embodiments have been described as examples of the invention, and variations thereof are also within the scope of the invention as defined by the following claims.

The lamp including the pressure discharge tube or the fluorescent tube according to the present invention has an excellent effect on photodynamic therapy (PDT) for various external skin diseases, and the treatment time is short and the cost is low.

Claims (46)

And a non-planar array of substantially straight discharge tubes arranged to emit light in a substantially visible spectrum region at a intensity of at least 3 mW / cm ² to the patient. A light source according to claim 1, wherein said tube is a fluorescent tube. The light source of claim 1 or 2, wherein the tube is arranged to emit light of a wavelength substantially defined in the 350-500 nm region. 4. The light source of claim 3, wherein the tube is arranged to emit light of a wavelength substantially defined in the 400-450 nm region. The light source according to claim 1, wherein the tubes are arranged along a curved surface perpendicular to the longitudinal direction of the tubes. 6. The light source of claim 5, wherein the tube is mounted on an inner curved surface of the housing arranged to cover at least a portion of the patient's body. 7. The light source of claim 6, wherein the housing is movable along the body of the patient to irradiate light onto at least a portion of the patient's body. 6. The light source of claim 5, wherein the tube is mounted on an inner cylindrical curved surface of the housing sized to irradiate light only to the lower half of the standing patient. 6. The light source of claim 5, wherein the tube is mounted on an inner curved surface of the housing that is sized to allow the patient to stand in the housing to irradiate light substantially throughout the patient's body. 4. A light source according to claim 1 or 3, wherein the tubes are mounted on at least two planes angled with each other. 11. The tube of claim 10, wherein the tube is a lower portion of the substantially horizontal surface on which the patient's leg lies beneath it when the patient is sitting, and a substantially vertical surface facing the lower leg of the patient when the patient is sitting. Light source, characterized in that mounted on the. 11. The light source of claim 10, wherein the tube is mounted on a first substantially planar member and a second substantially planar member attached by a movable joint to the first member. 13. The light source of claim 12, wherein the first planar member is arranged to irradiate light from the front to the face of the patient. 14. The light source of claim 12 or 13, wherein the second planar member is arranged to irradiate light onto the head of the patient. The light source of claim 12 or 13, wherein the second planar member is arranged to irradiate light from the side to the face of the patient. One or more discharge lamps arranged in the housing, an opening for allowing a portion of the patient's body to enter the housing, and mounted within the housing and emitting light from the one or more lamps when the portion of the patient's body is inserted into the housing. And a concave reflector arranged to be concentrated in the light source for treatment or diagnosis of the patient. A light source for patient treatment or diagnosis comprising at least one fluorescent grid lamp comprising a tube having a plurality of folds in the same plane. One or more medium / high pressure discharge lamps, and the body parts of the patient arranged close to the one or more medium / high pressure discharge lamps such that light therefrom can reach the body parts of the patient at an intensity of at least 3 mW / cm ^2. Light source for treatment of a patient, characterized in that it comprises a housing. 19. The light source of claim 18, wherein the or individual medium / high pressure discharge lamps have an arc length of at least 15 mm. The light source according to claim 18 or 19, wherein the or individual lamps are medium pressure lamps. 21. The light source of claim 20, wherein said lamp comprises mercury vapor. 22. The light source of claim 21, wherein the lamp further comprises a vapor of one or more elements selected from the group consisting of gallium, thallium, cadmium, indium and lead. 23. The light source of claim 22, wherein said lamp comprises vapor of at least one element selected from the group comprising cadmium, mercury, cesium, zinc, thallium and potassium. 24. The light source of claim 23, wherein said lamp comprises an inert gas. 25. The light source of claim 24, wherein said inert gas comprises one or more from the group comprising neon, argon and krypton. The light source according to claim 18 or 19, wherein the or individual lamps are high pressure lamps. 27. The light source of claim 26, wherein said lamp comprises sodium vapor. 28. The light source of claim 27, wherein said lamp further comprises xenon. 28. The light source of claim 27, wherein said lamp further comprises mercury. The light source of claim 1, wherein the intensity change over the treatment site of the patient is about 10% or less. 31. The light source of claim 30, wherein said intensity change is about 6% or less. 32. A light source as claimed in any of claims 18 to 31 comprising an array of substantially regular lamps of the lamps which are similar. The light source of claim 1, comprising a diffuse reflecting surface arranged to reflect light towards the patient. 33. A light source as claimed in any of claims 18 to 32, comprising at least one lamp and an opening for irradiating a patient with light from the at least one lamp. 35. The light source of claim 34, wherein said opening has a transparent or translucent cover. 36. The light source of claim 35, wherein the cover is arranged to filter a portion of the output spectrum of the one or more lamps. 37. The light source of claim 36, wherein said cover comprises a detachable filter. A plurality of low pressure discharge lamps mounted within the housing to allow light from the lamp to reach the patient, and a transparent or translucent cover over the opening, the cover having or including a detachable filter. Light source for patient care and diagnosis. Use of the light source according to any one of the preceding claims for the treatment of external skin diseases. 40. Use according to claim 39, wherein said treatment is for cosmetic purposes. Actinic / sun rays keratose, Bowen's disease, shallow basal cell carcinoma, basal carcinoma, epithelial carcinoma, fungal sarcoma, T-cell lymphoma, acne and sebaceous gland, psoriasis, eczema, seborrheic nevus, herpes simplex Use of a light source according to any one of claims 1 to 38 in the treatment of one or more diseases of viral infections, infectious continuous species, and warts (refractory warts, vulgar warts or plantar warts), alopecia areata, or hirsutism. . 42. Use according to claim 41, wherein said disease is an external disease. 43. Use according to any one of claims 39 to 42 for use in photodynamic therapy. 44. The use of claim 43, wherein the site of infection of said patient is treated with PpIX. A method of cosmetic treatment of a human or animal body, comprising applying a photosensitizer to a treatment site and irradiating the site with light from a light source according to any one of claims 1 to 38. A method of medical treatment of a human or animal body comprising applying a photosensitizer to a treatment site and irradiating the site with light from a light source according to any one of claims 1 to 38.