Surgery: light – thermal – and electrical application – Light – thermal – and electrical application – Light application
Patent
1997-06-06
1999-01-19
Lacyk, John P.
Surgery: light, thermal, and electrical application
Light, thermal, and electrical application
Light application
607 93, 606 16, A61N 500
Patent
active
058610200
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a device for irradiating body tissue with high intensity light, the device including a probe with at least one waveguide couplable with a laser light source on whose light exit section (which is insertable into body tissue) a diffuser element is provided which consists of a base material highly transparent for the laser light and scattering particles dispersed in this which deflect the light rays, and with a first cover tube surrounding the waveguide at a distance which can be connected with a coolant source, which is open at its distal end, and which consists of a transparent and good heat conducting material.
BACKGROUND OF THE INVENTION
The laser has been used since 1983 for interstitial heating of biological tissue. In the meantime, various probes and applicators have been developed to irradiate laser light into human tissue. Corresponding devices are described in German patent applications open to public inspection 38 13 227, 41 37 983, 42 13 053 and 42 21 364.
The previously described systems are constructed according to one more or less similar principle. The laser light is launched into an optical element located in the tip of the waveguide through a waveguide. Here as a rule it is a question of mirrors or prisms as well as special diffusers which permit an even irradiation of the laser light in all directions of space. These systems are provided in part with a cooling circuit for an additional modification of the temperature area profile, as this is, for example, described in DE-A-42 21 364, from which the preamble of claim 1 proceeds. A main problem of all interstitial heating procedures is, however, the exact adaptation of the temperature area profiles to the given tissue lesion. This will be sketched briefly with reference to the example of prostatic hyperplasia.
The prostate is divided anatomically into a right and a left prostate lobe as well as a median lobe. The geometrical extension is indeed similar in a normal prostate, apart from differences in size. The intensities of pathological changes are, however, extraordinarily different from patient to patient. In addition to a general enlargement of the prostate, there are also found isolated changes in the right or left prostate lobes as well as in the median lobe. Moreover, of course, very different combinations of these pathological changes can occur in individual cases. In addition to this, it frequently results that the target tissue reacts differently to laser radiation although the irradiation profile was adapted to the lesion. The temperature distribution can thus assume undesirably excessively high or, however, even too low temperatures during the irradiation. A similar problem emerges in connection with irregularly formed tumors, whereby especially the histological composition within the tumor (living cells, necroses, hemorrhages, vessels) can supervene in an aggravating manner. A laser probe which solves this problem has not been described until now.
SUMMARY OF THE INVENTION
A probe for irradiating body tissues with laser light is known from EP-A-439 629, which for achieving a uniform irradiation has a diffuser element and in which a reflector with light exit openings so surrounds the waveguide in the region of its light exit section that light preferably is emitted in the forward direction.
Underlying the invention is the object of constructing a device of the type named at the beginning such that it can be used in connection with a great number of specific pathological anatomical lesion shapes and permits an online adaptation of the laser output to various reactions within the irradiated tissue during the irradiation process.
This object is accomplished by arranging an installation in the path of the laser beam before the launching point for changing the beam intensity, and the waveguide is enclosed by a reflector and/or absorber in the area of its light exit section which has at least one light exit opening in the area of the desired radiation surface.
A first basic feature of a preferred embodiment
REFERENCES:
patent: 4383729 (1983-05-01), Suzuki et al.
patent: 4718417 (1988-01-01), Kittrell
patent: 4799479 (1989-01-01), Spears
patent: 5041109 (1991-08-01), Abela
patent: 5151096 (1992-09-01), Khoury
patent: 5207669 (1993-05-01), Baker et al.
patent: 5219346 (1993-06-01), Wagnieres et al.
patent: 5344419 (1994-09-01), Spears
patent: 5415655 (1995-05-01), Fuller et al.
patent: 5695493 (1997-12-01), Nakajima et al.
Lacyk John P.
Yarnell Bryan K.
LandOfFree
Apparatus for irradiating body tissue with laser light does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for irradiating body tissue with laser light, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for irradiating body tissue with laser light will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1243861