Surgery – Instruments – Means for concretion removal
Reexamination Certificate
1998-02-17
2001-02-13
Smith, Jeffrey A. (Department: 3732)
Surgery
Instruments
Means for concretion removal
Reexamination Certificate
active
06187017
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention provides a retrieval basket for use with a surgical device. In particular, it provides a basket adapted to capture calculi for removal from a surgical patient.
FIELD OF THE INVENTION
There is an ongoing demand for improved surgical devices that are capable of removing objects from a surgical patient's body. In the fields of urology and gastroenterology, for example, there is a demand for improved devices that are capable of capturing and retrieving calculi. Calculi in the urinary tract, commonly composed of calcium oxalate for example, cause pain whether they are positioned in the kidney or bladder or elsewhere and can be especially painful as they pass through a duct such as the ureter. Such calculi (or “stones”) often need to be removed surgically to avoid or to cure a urinary obstruction and possible infection.
Various retrieval baskets have been proposed over the years for calculi removal. They generally include wires formed to define a “cage” in an expanded position into which calculi can be maneuvered. A sheath is often provided to maintain the wires in a collapsed position for insertion. A handle is often provided for manipulation of the sheath and basket with respect to one another in order to move the basket or cage between the collapsed and expanded positions. In use, the basket is advanced distally to a position within the patient's duct that is beyond a calculus to be grasped while the basket is in the collapsed position within the sheath. It is subsequently expanded upon release from the sheath and drawn back proximally to capture the calculus.
So-called “flat-wire baskets,” such as the SURLOK Flat-Wire Stone Baskets offered by CIRCON SURGITEK (Part Nos. 57100XX), have been introduced to engage stones. They are formed from wires that are substantially straight and parallel to one another throughout the basket's length. Flat-wire baskets have been found to be advantageous in that a calculus captured within the basket can be deployed or released in some cases from the basket by the surgeon, if desired. Such release may be advantageous if the calculus cannot be extracted from the patient, i.e., if the calculus is too large or oversized in some dimension for easy extraction from a patient.
Despite the advantages of flat-wire baskets, it has been discovered in some instances that certain calculus shapes might not be easily grasped. Specifically, it has been discovered that the parallel wires of the basket define gaps that extend along the basket's length and that calculi can escape capture in some instances if they are aligned with one of these gaps as the basket is drawn back to grasp the calculi.
So-called “helical baskets”, such as the SURLOK Helical Stone Baskets provided by CIRCON SURGITEK (Part Nos. 57000XX), have also been introduced for calculi retrieval. Such helical retrieval baskets generally include wires that are formed into a helical configuration. They have been discovered to be advantageous in that they are extremely effective for capturing calculi for extraction and for securely retaining the captured calculi within the basket. Despite this significant advantage of conventional helical baskets, it has been discovered in some instances that they grasp calculi so well that it may become difficult to deploy or release a captured calculus from the basket if it is discovered to be too large for easy extraction from the patient.
U.S. Pat. No. 4,347,846 issued to Enrico Dormia describes a surgical extractor having a basket formed by wires arranged in pairs and disposed in helical paths wherein one wire of each pair is spiralled in a clockwise direction and the other in a counter-clockwise direction so that the wires of each pair intersect at a single point. The points of intersection are intended to constitute zones where the calculus body will be definitely imprisoned, being held firmly, without risk of escape.
Another example of a basket is described by James Bates et al. in U.S. Pat. No. 5,496,330. It includes pairs of wires that are expanded such that each pair of wires closely assumes a path along a helical turn with individual wires remaining closely adjacent throughout the length of the basket. The object was to provide a surgical extractor that increases the number of contact points with calculi in a retrieval basket to increase the reliability with which the retrieval basket entraps calculi.
OBJECT OF THE INVENTION
It is an object of this invention to provide an improved retrieval basket for a surgical device that overcomes the drawbacks of conventional baskets.
It is another object of this invention to provide a retrieval basket that is adapted to capture calculi securely yet may also be capable of releasing captured calculi, if desired.
Other objects and advantages of the invention will become clear in view of the following description.
SUMMARY OF THE INVENTION
This invention provides a retrieval basket adapted to capture calculi securely yet can also be adapted to release captured calculi, if desired. It includes a plurality of wires extending between the proximal and distal ends of the basket. The wires diverge radially away from the basket's axis along relatively straight or relatively parallel paths in a proximal portion of the retrieval basket. The wires also converge radially toward the basket's axis along substantially curvilinear paths, preferably helical, in the distal portion of the retrieval basket.
Each wire extends from the basket's proximal end and in a proximal portion of the basket closely adjacent to another wire and then diverges from the other wire at a location spaced from the basket's proximal end. Adjacent wires can either cross one another near the proximal end of the basket before diverging from one another or they can extend substantially parallel to one another near the proximal end without crossing.
The wires can also be formed so that they extend along a so-called “dual helical path” between the expanded basket's proximal and distal ends, wherein the wires extend along a proximal helical path and then extend along a distal helical path that has a smaller radius of curvature as compared to the proximal helical path.
REFERENCES:
patent: 4425908 (1984-01-01), Simon
patent: 5057114 (1991-10-01), Wittich et al.
patent: 5133733 (1992-07-01), Rasmussen et al.
patent: 5330482 (1994-07-01), Gibbs et al.
patent: 5484384 (1996-01-01), Fearnot
patent: 5792145 (1998-08-01), Bates et al.
patent: 0 123 175 (1986-09-01), None
patent: 391384 (1990-10-01), None
patent: 0 160 870 (1991-07-01), None
patent: 240173 (1969-03-01), None
patent: WO 92/16153 (1992-10-01), None
patent: WO 96/15728 (1996-05-01), None
English translation of Russian Patent No. 240173 of V.P. Pashkovskiy for Gallstone Extractor.
Circon Corporation
Ganz, Esq Bradley M.
Smith Jeffrey A.
LandOfFree
Retrieval basket for a surgical device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Retrieval basket for a surgical device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Retrieval basket for a surgical device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2581260