Surgery – Instruments – Cutting – puncturing or piercing
Reexamination Certificate
1999-10-20
2001-01-09
Buiz, Michael (Department: 3731)
Surgery
Instruments
Cutting, puncturing or piercing
C606S181000
Reexamination Certificate
active
06171325
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to techniques for incising a surface, and more particularly to techniques for incising skin of a patient to obtain a blood sample through a tubular channel.
BACKGROUND
The analysis and quantification of blood components is an important diagnostic tool for better understanding the physical condition of a patient. Since adequate noninvasive blood analysis technology is not currently available, blood samples still need to be obtained by invasive methods from a great number of patients every day and analyzed. A well known example of such needs is self-monitoring of glucose levels by a diabetic individual, e.g., performed at home. Upon doctors' recommendations and using such products, patients typically measure blood glucose level several (3-5) times a day as a way to monitor their success in controlling blood sugar levels. For many diabetics, the failure to test blood glucose regularly may result in damage to tissues and organs, such as kidney failure, blindness, hypertension, and other serious complications. Nevertheless, many diabetics do not measure their blood glucose regularly.
One important reason why patients fail to regularly take blood samples to self-monitor physiological conditions is that the existing monitoring techniques and products for sampling blood cause appreciable pain and discomfort during the sampling process. The current technique of self-administered blood sampling involves using lancets made of stainless steel cylindrical rods the tips of which are shaped to ease penetration into the tissue past the epidermis, into the dermis to rupture the blood vessels in the dermis. Typically, the lancet is propelled by a spring-loaded mechanism that pushes the sharp tip of the lancet into the skin. Studies on pain associated with blood sampling using lancets that are currently commercially available indicate that these lancets often cause considerable pain and large tissue damage. Attempts have been made to reduce pain by reducing the size of the lancet. However, this has not been shown to reduce the amount of pain to an acceptable level for many people.
Therefore, it is desirable to devise techniques of blood extraction and measurement that are easy to administer. There is a need for improved devices and methods for sampling blood that can be used with very little pain and discomfort to the patient.
SUMMARY
In one aspect, this invention provides multiple-shaft apparatuses for incising soft resilient substrates, e.g., body tissue. In an embodiment, the apparatus includes two or more incision shafts each having a distal edge. The shafts are non-fixedly associated with one another for relative motion to drive the distal edges against the body tissue at different velocities to incise the body tissue (hereinafter “tissue”).
The main cause of pain in blood sampling is believed to be the propagation of the pressure waves initiated by the impact of the lancet tip on the tissue. All the force needed for penetration is supplied in an instant by the spring in conventional lancet driving mechanisms. The total pressure on the tissue using such spring-loaded impact lancets is therefore large and consequently leads to significant pain. A multiple-shaft proboscis having a channel through which blood can be passed is applicable in an apparatus for drawing blood for sampling from a patient according to the present invention. The different shafts (or parts of the proboscis) cut into the tissue at different times, e.g., by a reciprocative motion as the proboscis is advanced against the tissue. This invention reduces pain associated with sampling blood via a needle-like structure being inserted into the body tissue. The intermittent, “stop and go” motion of the cutting edges of the proboscis helps the cutting edges to cut into the tissue as they are advanced into the tissue. This intermittent cutting results in small penetration steps and very small penetration pressure being applied to the tissue through the pushing action of the proboscis. The intermittent cutting motion is preferably reciprocative, i.e., reciprocating, i.e., with a reverse in direction periodically. The intermittent cutting motion can also be either longitudinal or rotational. Small pressure resulting from such cutting motions effects extremely low stimulation to the nerve endings at the tissue being cut for blood sampling. As a result, very little pain is sensed by the patient in the blood sampling procedures of the present invention.
REFERENCES:
patent: 4469110 (1984-09-01), Slama
patent: 4577630 (1986-03-01), Nitzsche et al.
patent: 4600014 (1986-07-01), Beraha
patent: 4712548 (1987-12-01), Enstrom
patent: 4877026 (1989-10-01), de Laforcade
patent: 5133730 (1992-07-01), Biro et al.
patent: 5167619 (1992-12-01), Wuchinich
patent: 5196025 (1993-03-01), Ranalletta et al.
patent: 5211652 (1993-05-01), Derbyshire
patent: 5266359 (1993-11-01), Spielvogel
patent: 5318583 (1994-06-01), Rabenau et al.
patent: 5318584 (1994-06-01), Lange et al.
patent: 5395387 (1995-03-01), Burns
patent: 5459325 (1995-10-01), Hueton et al.
patent: 5571132 (1996-11-01), Mawhirt et al.
patent: 5613978 (1997-03-01), Harding
patent: 5857983 (1999-01-01), Douglas et al.
patent: 29800611 U (1998-01-01), None
patent: WO92/03099 (1992-03-01), None
patent: WO96/14799 (1996-05-01), None
patent: WO97/28741 (1997-08-01), None
patent: WO98/19609 (1998-05-01), None
patent: WO99/07295 (1999-02-01), None
Edited by Berardesca, M. D., et al., “Bioengineering of the Skin: Methods and Instrumentation”, 1995, pp: 1-13, CRC Press, Boca raton, New York.
Rothman, M. D., “Physiology and Biochemistry of the Skin”, pp. 8-25, The University of Chicago Press.
Tregear, “Physiology Interpretation of Skin Impedance Measurements”, pp. 600-601, 1965, vol. 205, Nature.
Lawler, et al., “Electrical Characterestics of the Skin, The Impedance of the Surface Sheath and Deep Tissues”, pp. 301-308, vol. 34, Journal of Investigative Dermatology.
Cimino, et al., “Physics of Ultrasonic Surgery Using Tissue Fragmentation”, pp. 1597-1600, 1995, IEEE Ultrasonics Symposium.
Lal, “Micromachined Silicon Ultrasonic Longitudinal Mode Actuators: Theory . . . ”, pp. 129-133, 1996, University of California, Berkeley (A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy).
Letourneau, et al., “Aspiration Biopsy”. pp. 8-29, General Considerations.
Greenstein Michael
Lum Paul
Mauze Ganapati R.
Verdonk Edward D.
Bui Vy Q.
Buiz Michael
LandOfFree
Apparatus and method for incising 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 and method for incising, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for incising will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2547853