Surgery – Radioactive substance applied to body for therapy – Combined with other radiant or wave energy source
Reexamination Certificate
2000-06-22
2002-04-16
Casler, Brian L. (Department: 3737)
Surgery
Radioactive substance applied to body for therapy
Combined with other radiant or wave energy source
C600S439000, C600S459000
Reexamination Certificate
active
06371903
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a therapy probe, which includes a therapy transducer movably mounted on a probe body. Such probes are used for prostate treatment using focused ultrasound, via rectal application. Such probes are also used for treating the esophagus, the stomach, the liver and, more generally in percutaneous treatment or treatment by laparoscopy.
The probes advantageously include an imaging transducer that enables the treated region to be visualized during treatment.
WO-A-8907909 discloses a therapy and imaging probe for endocavital use, including a therapy transducer that is movable in a rotary manner, and an imaging transducer that is movable linearly. The linear and rotational movements are independent.
FR-A-2,673,542 (WO-A-9215523 or U.S. Pat. No. 5,474,071) discloses a therapy and imaging probe, including a spoon-shaped therapy transducer with an associated imaging transducer. The two transducers do not move with respect to each other.
FR-A-2,708,207 discloses a therapy and imaging probe, including a spoon-shaped therapy transducer. The therapy transducer is movable in a rotary manner, and the imaging transducer is movable linearly. FR-A-2,715,822 discloses a therapy and imaging probe in which the therapy transducer and the imaging transducer are movable and are driven by common drive means. U.S. Pat. No. 5,720,287 claims priority of these two French applications.
N. Bom et al., “Early and recent intraluminal ultrasound devices”, International Journal of Cardiac Imaging, 4:79-88 (1989), discloses various types of imaging or treatment probes.
U.S. Pat. No. 5,762,066 discloses a therapy probe having a rotatable transducer and non-distentable acoustic membrane to ensure that tissue does not protrude into an interior volume of the probe housing. This reference suggests circulating a degassed coupling fluid to cool the probe and prevent the formation of bubbles.
The above-described therapy probes seek to provide therapy that is as effective and accurate as possible. If an imaging transducer is provided, another goal is to allow the treated region to be visualized, preferably during treatment. Finally, regarding endocavital probes, the total probe volume or cross-section is also an important parameter.
With respect to prior art probes, it has been suggested to insert the probe into a flexible casing or to provide a flexible casing in the probe. After the probe is inserted into the body cavity, the flexible casing may be deformed into contact with the tissue of the patient. The casing is deformed, e. g. by inflating it with a liquid. Such liquid may include degassed water. For example, see FR-A-2,715,822 or U.S. Pat. No. 5,676,692. U.S. Pat. No. 5,720,287 also discloses a probe with a flexible casing. The flexible casing is inflated during treatment, and fluid is circulated to cool the transducers.
EP-A-0 815 901 discusses the problem of patient movement during treatment. Such movement can lead to the probe moving with respect to the patient, or moving with respect to the organ to be treated or visualized. The reference also discusses the guiding and maintaining of the probe with respect to the patient. In international application WO-A-8907909 for prostate treatment, it is proposed to apply a rotary movement about the general axis of a rectal probe. In FR-A-2,673,542 for prostate treatment, an endorectal treatment and imaging probe is provided, together with a urethral imaging probe. While the two probes are being positioned, it is proposed to move the probes in the plane of symmetry of the patient to bring the probes closer together or further apart. The relative position of the probes is then “frozen” for treatment. During treatment, the two probes are rotated independently of each other about their respective longitudinal axes, and are moved linearly along their parallel longitudinal axes, i.e. essentially parallel to the rectum. FR-A-2,708,207 proposes a probe mounted for linear movement in three directions, and for rotation about its longitudinal axis. FR-A-2,715,822 discloses a probe mounted for rotation about its longitudinal axis in a collar fixed to one end of a rod. The other end of the rod is mounted in a swivel joint allowing rotation in a vertical plane. The swivel joint is mounted for linear movement along two axes, in the same vertical plane.
Yet another problem discussed in EP-A-0 815 901 involves movements of the probe with respect to the organ to be treated. As discussed above, rotation of the probe about its longitudinal axis creates problems as it can lead to movement of the organ to be treated, particularly if the probe does not have a cylindrical cross-section. This particular problem does not occur in the case of the probe disclosed in FR-A-2,715,822 where the therapy transducer and the imaging transducer are arranged inside a rigid, cylindrical probe body. This solution, however, increases probe diameter or requires a decrease in the size of the therapy transducer, which is difficult to achieve. To overcome these problems, EP-A-0 815 901 suggests using a guard ring for limiting deformation of the flexible casing at the time a therapy transducer moves from a therapy position to an imaging position.
SUMMARY OF THE INVENTION
The invention resolves problems associated with prior art probes. Some of the above-described problems apply to all probes regardless of whether they include an imaging transducer, while other problems occur when the probes have both a therapy transducer and a imaging transducer.
Some of the problems addressed by the prevent invention relates to inflation of the flexible casing. The casing is deflated for inserting the probe into the cavity so as to facilitate insertion of the probe, typically in the case of a rectal or urethral probe. The casing is then inflated to ensure contact with the tissues of the patient. A liquid is used to inflate the casing and to permit transmission of the ultrasound from the transducers through the liquid. One problem discovered by the inventors of the present invention is that inflation of the casing causes bubbles to appear in the liquid. If the fluid is circulated during treatment, e.g. for the purposes of cooling the transducers, the bubbles may cause problems before they eventually disappear. Another problem is that bubbles may appear during treatment due to the ultrasound waves. Such bubbles have not been eliminated in prior art devices.
The present invention provides a solution to the problem of bubble formation in the liquid when liquid is used to inflate the flexible casing. The above-described problems are resolved by the present invention, which provides a therapy probe for use in a body cavity including a therapy transducer mounted on a support and movable with respect to a probe body between a therapy position and a retracted position. Also included is an at least partially deformable flexible casing around the therapy transducer, a guard ring for limiting deformations of the flexible casing in front of the transducer when the transducer is moved with respect to the probe body from the therapy position to the retracted position, a first opening for injecting liquid into the flexible casing, and a second opening for withdrawing liquid from the flexible casing, where one of the openings is formed on the guard ring.
The present invention also provides a therapy apparatus including the probe described above and a pump connected to the probe for circulating liquid in the flexible casing through the first and second openings.
In a preferred embodiment of the invention, the therapy transducer is rotatable about an axis substantially parallel to the longitudinal axis of the probe, and the guard ring extends from the probe body to a point on the transducer located on the axis. It is advantageous that the therapy transducer have a rectangle shape and that the guard ring extend along two adjacent sides of the transducer. The opening formed on the guard ring may be located substantially in the middle of the length of the guard ring. In another embodiment of the
Blanc Emmanuel
Chaussy Christian
Thüroff Stefan
Casler Brian L.
Cohen Eric D.
Qaderi Runa Shah
Technomed Medical Systems S.A.
Welsh & Katz Ltd.
LandOfFree
Therapy probe does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Therapy probe, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Therapy probe will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2915860