Fiduciary markers and method of use thereof

Abstract

The invention provides devices and methods used to locate target areas within a patient for repeat therapeutic treatments. In the invention, fiduciary markers made of metal or metal alloys are placed within a patient near or at a target site as reference coordinates for particular body locations on the patient. Repeat treatments may then be given to the patient over a period of time based on the coordinates given by the fiduciary markers. The fiduciary markers are specially shaped or put into strand to improve marker attachment and prevent marker migration.

1 . A marker for locating regions of interest in a subject comprising of at least one radio-opaque seed,
 a. wherein said radio-opaque seed remains readily detectable in vivo using common imaging modalities; and   b. said marker being sized and shaped for firm implantation into tissue or organ of said subject;   c. said radio-opaque seed has a length ranging from 0.1 mm to 5 cm;   d. said radio-opaque seed is made of a biocompatible metal or alloy of metals;   e. said radio-opaque seed have a proximal end and a distal end; and   f. a plurality of fingers is affixed to said distal end of the radio-opaque seed.   
     
     
         2 . A marker of  claim 1 , wherein said radio-opaque seed is made of a metal or metal alloy comprising as least one metal or metal alloy selected from the group consisting of stainless steel, gold, titanium, platinum, tantalum, copper, and tungsten. 
     
     
         3 . A marker of  claim 1 , wherein said radio-opaque seed is made of titanium. 
     
     
         4 . A marker of  claim 1 , wherein said radio-opaque seed can be of any shape. 
     
     
         5 . A marker of  claim 1 , wherein
 a. said distal end of the radio-opaque seed is shaped as a cone;   b. said proximal end of the radio-opaque seed is shaped as a ball; and   c. said proximal end and distal end is connected by a substantial cylindrical portion.   
     
     
         6 . A marker of  claim 5 , wherein the fingers
 a. remain closed before said seed is implanted into the subject; and   b. open up when said seed is implanted into a desired tissue within the subject.   
     
     
         7 . A marker of  claim 1 , wherein at least one said radio-opaque seed is enclosed in absorbable material forming substantially a strand. 
     
     
         8 . A marker of  claim 7 , wherein in the absorbable material is made of a polymer selected from a group consisting of
 a. a Polydextran;   b. a Polyvinylpyrrolidone;   c. a Poly(bis(p-carboxyphenoxy)-propane); or   d. a Biopolymer.   
     
     
         9 . A marker of  claim 7 , wherein at least two said radio-opaque seed is separated by at least one absorbable spacer. 
     
     
         10 . A marker of  claim 9 , wherein said absorbable spacer is made of a polymer selected from a group consisting of
 a. a Polydextran;   b. a Polyvinylpyrrolidone;   c. a Poly(bis(p-carboxyphenoxy)-propane); or   d. a Biopolymer.   
     
     
         11 . A marker of  claim 10 , wherein said biopolymer is selected from group consisting of gelatin, human serum albumin, and cellulose. 
     
     
         12 . A marker of  claim 1 , wherein at least one said radio-opaque seed is wrapped in surgical suture. 
     
     
         13 . A marker of  claim 12 , wherein at least two said radio-opaque seeds are wrapped in surgical suture to form a strand. 
     
     
         14 . A marker of  claim 13 , wherein at least two said radio-opaque seed is separated by at least one absorbable spacer. 
     
     
         15 . A marker of  claim 14 , wherein said absorbable spacer is made of a polymer selected from a group consisting of
 a. a Polydextran;   b. a Polyvinylpyrrolidone;   c. a Poly(bis(p-carboxyphenoxy)-propane); or   d. a Biopolymer.   
     
     
         16 . A marker of  claim 19 , wherein said biopolymer is selected from group consisting of gelatin, human serum albumin, and cellulose. 
     
     
         17 . A method of locating a region of interest in a subject for treatment using a marker, comprising the following steps:
 a. producing a marker comprising of at least one radio-opaque seed wherein said seed remains readily detectable in vivo using common imaging modalities; and sized and shaped for firm implantation into tissue or organ of said subject;   b. implanting one or more of said marker into said tissue or organ close to or at said region of interest   c. opening a plurality of fingers on said radio-opaque seed;   d. fixing said radio-opaque seed into tissue;   e. detecting said marker in vivo using common imaging modalities;   f. locating said region of interest using said markers as reference points; and   g. delivering treatment to the region of interest.   
     
     
         18 . A method of  claim 17 , wherein said common imaging modalities includes:
 a. Stereotaxy;   b. Ultrasound;   c. CT; or   d. MRI.   
     
     
         19 . A method of  claim 18 , wherein said markers are implanted using one of the following method:
 a. an implantation gun;   b. a catheter; and   c. a syringe.   
     
     
         20 . A method of  claim 19 , wherein said marker
 a. is implanted for a period of time,   b. is used in a series of treatments; and   c. is removed after said treatments.