Contrast media dispensing apparatus

A dispensing system and apparatus for introducing contrast media intravascularly during catheterization procedures, which apparatus includes connected segments of tubing that serve as a flow path into the vascular system. A spike is provided at one end of a first segment of the tubing for "spiking" a bottle of contrast media. A stopcock is also provided in the first segment of tubing and a luer lock fitting is attached to the stopcock for connecting a second segment of tubing to the stopcock. A top check valve is provided in the second segment of tubing, which extends from the stopcock. A bottom check valve is provided in the second segment of tubing spaced from the first check valve and a bottom stopcock is also provided in the second segment of tubing below the bottom check valve. A third length of IV tubing projects from the bottom stopcock and receives a second luer lock fitting for securing the bottom end of the third length of IV tubing to a conventional manifold. When the dispensing system is operational, contrast fluid is allowed to flow through the first and second segments of tubing by manipulating the top stopcock, it then flows into the manifold by manipulating the bottom stopcock and is injected intravascularly into the body from the manifold during the catheterization procedure.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
Many techniques and various apparatus for administration of various fluids 
intravenously into the body for a variety of purposes are well known in 
the art. Solution administration devices are commonly known as 
intravascular or "IV" systems and generally include a tubular flow line of 
selected length having a spike at the upper end which may be inserted into 
an IV solution bag or bottle and a catheter tip at the opposite end for 
infusing fluid from the bag or bottle into a patient's vein or artery. The 
flow line or tube also typically includes a flow regulator in the form of 
a drip chamber and an automated or a thumb-operated device for controlling 
the rate of fluid flow from the bag or bottle into the flow chamber and to 
the patient. Variations of this IV system are used during heart 
catheterization procedures, where a catheter is inserted in a patient's 
artery or veins, extended into the heart or other area of investigation 
and a supply of diagnostic radiopaque contrast media is injected from a 
manifold into the vascular system for angiography in this area. The 
contrast media is conventionally used for angiography throughout the 
cardiovascular system, including cerebral and peripheral arteriography, 
coronary arteriography, ventriculography and the like. Intravascular 
injection of the radiopaque diagnostic agent contrast media opacifies 
those vessels in the path of flow of the contrast media, permitting 
radiographic visualization of the internal structures of the human body. 
Although the contrast media is particularly well indicated and effective 
for angiography throughout the cardiovascular system, it is very 
expensive. 
During normal catheterization procedures where contrast media is used, a 
bottle of contrast media is typically suspended and spiked by one end of a 
conventional IV apparatus, the opposite end of which is attached to a 
manifold to facilitate injection of contrast media into the area of 
investigation at the proper time. Each such procedure requires varying 
amounts of contrast media and upon completion of each procedure, the IV 
tubing and unused contrast media, still in the contrast media bottle, are 
discarded, regardless of the quantity of contrast media remaining in the 
bottle. This procedure is necessary to avoid the possibility of 
contamination of the contrast media remaining in the bottle due to 
pathogens which may reverse-flow by reflux through the IV tubing from the 
patient into the contrast media. This normal operating technique 
frequently results in a significant expensive waste for many 
catheterization procedures, depending upon the quantity of contrast media 
remaining in the dispensing bottle after the procedure has been completed. 
2. Description of the Prior Art 
Various types of intravenous systems are well known in the art. Early such 
apparatus are detailed in U.S. Pat. No. 2,866,457, dated Dec. 30, 1958, to 
R. C. Moore; U.S. Pat. No. 2,999,499, dated Sep. 12, 1961, to R. H. 
Willet; U.S. Pat. No. 3,001,525, dated Sep. 26, 1961, to G. E. Hendricks; 
U.S. Pat. No. 3,057,350, dated Oct. 9, 1962, to C. C. Cowley; U.S. Pat. 
No. 3,533,400, dated Oct. 13, 1970, to William E. Polich; U.S. Pat. No. 
3,776,229, dated Dec. 4, 1973, to Charles J. McPhee; U.S. Pat. No. 
3,951,145, dated Apr. 29, 1976, to B. L. Smith; and U.S. Pat. No. 
4,055,176, dated Oct. 25, 1977, to I. H. Lundquist. U.S. Pat. No. 
4,078,563, dated Mar. 14, 1978, to Robert D. Tuseth, details a "Disc Valve 
In A Container For Dispensing Liquids". The patent describes an improved 
disc valve which includes at least two upstanding posts adjacent an outlet 
passage in the bottom of the container and a floatable disc member with 
apertures near its periphery, through which the posts extend. The posts 
are fitted with disc-retaining stops at the upper end and position the 
disc, and the relationship between the size of the apertures and the 
thickness of the posts assures that the disc will seat over the outlet 
passage to prevent the passage of air when all the liquid has been 
dispensed. U.S. Pat. No. 4,175,558, dated Nov. 27, 1979, to John M. Hess, 
III, details a "Parenteral Liquid Administering Device" which includes an 
enlarged chamber for receiving liquid from a source. A bottom flow valve 
in the chamber controls flow from the chamber, the valve having an 
air-tight, sealed float system. U.S. Pat. No. 4,325,368, dated Apr. 20, 
1982, to E. Kaemmerer, details an infusion device having a dual chamber 
with two dispensing mechanisms for dispensing two fluids from the 
chambers. U.S. Pat. No. 4,425,123, dated Jan. 10, 1984, to F. Di Salvo, 
details a "Parenteral Liquid Application Apparatus". The apparatus 
includes a liquid flow control device fitted with a membrane which 
intermittently closes and opens flow communication from beneath the 
dripping tube. A cannula serves to apply the liquid to the patient, the 
side of the membrane remote from its control side being connected by a 
capillary tube to the interior of the dripping tube to equalize the 
pressure changes occurring on both sides of the membrane as the liquid 
level and supply vessel decreases. The flow rate is initially adjusted by 
lowering the level of the liquid stabilization device with respect to the 
level of the dripping chamber. U.S. Pat. No. 4,428,383, dated Jan. 31, 
1984, to W. A. DeVoom, details a "Manifold for Monitoring Hemodynamic 
Pressure". The manifold assembly includes a base having first, second and 
third flush valves mounted thereon. A first three-port stopcock is also 
mounted on the base and has one of its ports in fluid communication with 
the first flush valve. One of the ports is in fluid flow communication 
with an arterial catheter and one of the ports is in fluid communication 
with a pressure monitoring device for determining arterial pressure. The 
first T-connector is fastened to the second flush valve and a second 
T-connector is fastened to the third flush valve. A second three-port 
stopcock is mounted on the base with one of its ports in fluid flow 
communication with the second flush valve through the first T-connector. 
One of the ports of the second three-port stopcock is in fluid flow 
communication with the third flush valve through the second T-connector. 
U.S. Pat. No. 4,534,757, dated Aug. 13, 1985, to Leo Geller, details a 
device for releasing an active ingredient into a liquid flow passing 
through a system for parenterial application of the ingredient. The device 
includes a receptacle having two half shelves and subdivided by a ribbed 
aluminum foil into two chambers with an inlet at its upper end and an 
outlet at the lower end. The chambers have vents at their upper ends and 
one of the chambers contains two overflows, a first one of which empties 
into the outlet while the second overflow empties into the other chamber. 
In the latter chamber, there is present a further overflow which also 
empties into the outlet, as well as a plate-shaped carrier charged with 
the active ingredient to be released. The liquid flows from the inlet by 
means of the first chamber and the second overflow into the other chamber 
and from there upwardly past a carrier charged with the active ingredient 
and onward by means of a third overflow and the other chamber into the 
outlet. U.S. Pat. No. 4,548,598, dated Oct. 22, 1985, to Felix Theeuwes, 
details a Parenteral Agent Dispensing Equipment which includes a drip 
chamber and a formulation chamber. The formulation chamber includes a wall 
surrounding an internal space and has an inlet for admitting a liquid into 
the formulation chamber and an outlet for letting an agent formulation 
leave the formulation chamber. The chamber houses an agent delivery system 
for releasing a beneficial agent into a liquid that enters the chamber. 
U.S. Pat. No. 4,734,091, dated Mar. 29, 1988, to William J. Boyle, et al, 
details a "Filtered Manifold Apparatus and Method For Ophthalmic 
Irrigation". The device is designed to provide ophthalmic irrigation by 
sterile filtered irrigation fluid into the eye at high flow rates. The 
apparatus includes a filter capable of removing particles on the order of 
0.8 microns and preferably as small as 0.22 microns. A distribution 
manifold facilitates the flow of fluid from a common reservoir 
sequentially to multiple recipient sites. U.S. Pat. No. 4,750,643, dated 
Jun. 14, 1988, to Theodore S. Wortrich, details a "Sterile Fluid 
Dispensing System and Method". The system is disposable to enable a 
succession of individuals to be supplied with a sterile medical solution 
during operative and other procedures. The system uses a number 
spaced-apart, penetrable, elastomerically sealed funnels branching from an 
outlet from the solution container or attached drip chamber. A standard 
sterile administration set having a spike end may be inserted into the 
seal of a first funnel to provide flow to a first individual. After the 
first procedure is completed, the conduit to the first funnel is clamped 
and the sequence is repeated, but with the spiked end of a second 
administration set inserted for supply to a second individual. The 
sequence may be repeated for a selected number of branches. U.S. Pat. No. 
4,858,619, dated Aug. 22, 1989, to Marie A. Toth, details an "Intracranial 
Pressure Monitoring System". The device includes a first valve having a 
first input port and first and second output ports, with the first output 
port adapted for connection to a drainage collection bag. A tube connects 
the input port of the first valve to a patient. A second valve has an 
input port connected to the second output port of the first valve. A dome 
member has a first opening for connection with an input port of the second 
valve, a second opening for receiving a pressure transducer and a third 
opening to permit balancing of the system. Through this configuration, the 
drainage collection bag is located before the pressure sensor, but at a 
maximum distance from the patient to reduce the risk of infection and an 
automatic relief valve may replace the second valve to provide for 
automatic venting of dangerously high levels of intracranial fluids. U.S. 
Pat. No. 4,869,457, dated Sep. 26, 1989, to G. Ewerlof, details an 
"Arrangement For Controlling and Regulating a Liquid Flowing Through a 
Line". The arrangement includes a valve body provided with a press-on or 
deforming element movable along the line and designed to cooperate with 
the line for regulating the flow of the liquid by means of restriction of 
the liquid to varying degrees. In the line there is fitted a continuous 
hollow element having a number of openings through which the liquid can 
flow. The press-on element movable along the hollow element is designed to 
press the line against the element. In this manner a shifting of the 
press-on element can be carried out such that an optimal area of the 
openings can be uncovered for through-flow of the liquid since that part 
of the hollow element where the area is located is situated on the outlet 
side with respect to the press-on element. The openings of the hollow 
element can be uncovered to varying degrees by means of the press-on 
element arranged in the valve body, the line being pressed against the 
openings of the hollow element in such a manner that the flow is 
restricted in varying degrees. An "Intravenous Administration System" is 
detailed in U.S. Pat. No. 4,892,524, dated Jan. 9, 1990, to Gordon Smith. 
The apparatus is designed to administer a volumetric flow of parenteral 
liquids into a patient's system, through which the quantity of liquid 
flowing into the system may be easily adjusted. The apparatus includes two 
separate hydrostatic head pressure systems. The first head pressure is 
applied from a container through a metering device with an adjustable 
fixed orifice, to a regulator located a fixed distance below the 
container. The second head is applied from the regulator, which is 
designed to prevent air flow through it to the patient. U.S. Pat. No. 
4,976,685, dated Dec. 11, 1990, to Frank E. Block, Jr., details a "Method 
of Blood-Gas Interface Control in Surgical Gas Traps". The blood is stored 
under refrigeration at a temperature of about 4 degrees Centigrade when it 
is utilized on a relatively rapid basis within a surgical heater. It is 
transported by tubing through a blood warming apparatus which, while 
warming the blood, causes an out gas of entrained air. This air is trapped 
in an air trap receptacle having a drip chamber, within which a gas-blood 
interface is developed. To assure that the capacity of the trap is not 
exceeded, an improved technique of gas removal and interface level setting 
is provided, wherein access is achieved essentially through the entrance 
region of the gas trap receptacle. U.S. Pat. No. 5,059,173, dated Oct. 22, 
1991, to John J. Sacco, details an IV Apparatus. The IV apparatus includes 
a gravity flow path fluid for administering IV fluids to a patient, in 
which multiple IV fluids can be delivered at different flow rates to the 
patient without having to replace the system apparatus. U.S. Pat. No. 
5,074,334, dated Dec. 24, 1991, to T. Onodera, details a "Multi-Way Cock". 
The multi-way cock includes a housing, including multiple branch tubes 
extending from the periphery thereof, and a plug including a barrel 
adapted to be rotatably fitted in the cylinder and having a corresponding 
number of channels formed therein, the channels corresponding to the 
branch tubes in assembled condition. U.S. Pat. No. 5,078,688, dated Jan. 
7, 1992, to Richard Lobodzinski, details a "Paracentesis Catheter System". 
The system is designed to remove fluid from the patient's abdominal cavity 
and for administering medication into the abdominal cavity. The catheter 
system includes a solid stylet, a catheter, a hemostasis valve assembly 
connected to the catheter and delivery tubing with the needle connecting 
the catheter assembly to a stopcock. The stopcock has provisions for 
connection alternately to a syringe or to a vacuum bottle or drainage bag. 
The hemostasis valve includes an internal gland which is compressed to 
shutoff fluid flow through the end of the valve assembly after removing 
the solid styler. This causes fluid to be diverted through the side arm 
tubing and stopcock to a fluid collection container. U.S. Pat. No. 
5,084,031, dated Jan. 28, 1992, to Robert J. Todd, et al, details a 
"Cardioplegia Three-Way Double Stopcock". The stopcock includes a hollow 
valve body with three solution infusion ports communicating to the 
interior thereof in a coplanar arrangement at a first longitudinal point 
on the valve body. Three cardioplegia pressure monitoring ports also 
communicate through the valve body to the interior thereof at a second 
longitudinal position distinct from the first. Mounted in the valve body 
is a cylindrical valve core selectively rotatable about the longitudinal 
axis thereof between a first position in which the cardioplegia solution 
source and the pressure monitor are coupled to the antigrade cannula and a 
second position in which the cardioplegia solution source and the pressure 
monitor are coupled to the retrograde catheter formed in the valve core or 
a set of valving passageways for communicating with selective ones of the 
infusion ports and a set of valving passageways for communicating with 
selective ones of the pressure monitoring ports. U.S. Pat. No. 5,135,026, 
dated Aug. 4, 1992, to Wayne E. Manska, details a "Medical Valve Having 
Fluid Flow Indicia". The medical valve includes a rotatable member having 
a fluid flow path formed by a passageway. The flow path indicia on a 
surface of the rotatable member follows a path along the surface which 
substantially replicates the fluid flow path of the passage, so as to 
indicate the orientation of the fluid flow path. U.S. Pat. No. 5,167,643, 
dated Dec. 1, 1992, to Lawrence A. Lynn, details a "Needle Protection 
Station". The station is designed for temporarily housing the tip and 
shaft of a needle or blunt cannula within a protected environment in which 
an elastomeric core extends into a bore formed in a housing having a 
tubular shape. An integral shield extends outwardly from the tubular 
housing between proximal and distal ends and protects the fingers during 
use. A portion of the housing between the closed end and the shield serves 
as a handle. Most preferably, the elastomeric core and housing are molded 
together by insert or core molding. U.S. Pat. No. 5,238,026, dated Aug. 
24, 1993, to N. Goto, details a "Liquid Outflow Control Unit". The liquid 
outflow control unit is used as an instrument for injecting a liquid such 
as a liquid medicine into a human body. It includes multiple, separate 
partial members, at least one of which has a groove on a joined face to 
form a small path through which a liquid may pass. The liquid enters one 
end of the groove and flows out of an exit and communicates with the other 
end of the groove. The liquid flowing out of the exit is injected into the 
human body by means of a connection tube and needle. A "NAMIC Contrast 
Controller" IV system is marketed by NAMIC U.S.A. Corp. of Glen Falls, 
N.Y., and includes a spike for spiking a bottle of contrast media, a 
stopcock and check valve provided in the fluid tubing connected to the 
spike and a graduated chamber for containing contrast fluid. 
It is an object of this invention to provide a contrast media dispensing 
system or apparatus for dispensing contrast media from a source of supply 
to a patient, wherein the system allows contrast media unused from a first 
procedure to be utilized in a second procedure without fear of media 
contamination during the first procedure. 
Another object of this invention is to provide a contrast media dispensing 
apparatus for safely using substantially all of the contrast media located 
in a bottle in more than one catheterization procedure, which apparatus 
includes a spike for spiking a contrast media bottle and a first length of 
tubing attached to the spike and provided with a top stopcock having a 
luer lock fitting for attachment to a second length of tubing provided 
with a pair of spaced check valves and terminating in a bottom stopcock. A 
third length of tubing extends from the bottom stopcock and is fitted with 
a luer lock fitting for attachment to a conventional manifold. The 
contrast media may be selectively drained from the bottle into the 
manifold during a first catheterization procedure, the entire apparatus 
below the top stopcock then removed and discarded after the first 
procedure, a second sterile apparatus attached to the in-place first 
length of tubing and a second catheterization procedure undertaken without 
contaminating the contrast media remaining in the bottle. 
Yet another object of this invention is to provide a contrast media 
dispensing apparatus for dispensing contrast media from a supply bottle in 
multiple sequential catheterization procedures without contaminating the 
remaining contrast media, which apparatus includes a spike for spiking the 
contrast media bottle, a vent provided in or near the spike, a first 
length of IV tubing fitted with a stopcock and a luer lock fitting for 
attachment to a second length of tubing having a pair of spaced check 
valves and terminating in a second stopcock. A third length of IV tubing 
extends from the second stopcock to another luer lock fitting, for 
attachment to a conventional manifold, wherein the connected second IV 
tubing, check valves, second stopcock and third IV tubing may be discarded 
after the first procedure and a second like apparatus attached to the top 
stopcock, for using substantially all of the contrast media in the bottle 
without fear of contaminating the contrast media remaining in the bottle 
during the first or subsequent procedure. 
Still another object of this invention is to provide a contrast media 
dispensing apparatus for dispensing contrast media from a supply bottle in 
multiple catheterization procedures without contaminating the contrast 
media during each procedure, which apparatus includes a vented or unvented 
spike for spiking the rubber plug in the contrast media bottle and a first 
length of IV tubing fitted with a stopcock having a luer lock fitting for 
attachment to a second length of IV tubing having a pair of spaced check 
valves. A third length of IV tubing extends from a second stopcock 
connected to the second length of IV tubing and the third length of IV 
tubing terminates in a second luer lock fitting for attachment to a 
conventional manifold, wherein the second length of IV tubing, check 
valves, second stopcock and third length of IV tubing may be discarded 
after the first procedure and a second twin apparatus attached to the top 
stopcock and the original first length of tubing for using substantially 
all of the contrast media in the bottle without contaminating the contrast 
media in the bottle during the first procedure. 
SUMMARY OF THE INVENTION 
These and other objects of the invention are provided in a contrast media 
dispensing apparatus for dispensing contrast media-from a supply bottle in 
multiple catheterization procedures without contaminating the contrast 
media during each procedure, which apparatus includes a vented or unvented 
spike for spiking the rubber plug in the contrast media bottle, a first 
length of IV tubing extending from the spike and terminating at a top, 
selectively vented, stopcock, a second length of tubing attached to the 
top stopcock by means of a luer lock and having a top check valve and a 
bottom check valve spaced from the top check valve, the second length of 
IV tubing terminating in a bottom stopcock, and a third length of tubing 
extending from the bottom stopcock and adapted for connecting to a 
conventional manifold.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIGS. 1-3 of the drawings, the contrast media dispensing 
apparatus of this invention is generally illustrated by reference numeral 
1. The dispensing apparatus 1 includes a first length of tubing 2, having 
one end fitted with a tubing spike 3, having a spike tip 3a, for extending 
through or "spiking" a rubber plug 41, located in the mouth of a contrast 
media bottle 40. The tubing spike 3 thereby accesses a supply of contrast 
media located in the contrast media bottle 40, for disposition as 
hereinafter described. A vent 4 is either built into the tubing spike 3 or 
may be otherwise provided in the first length of tubing 2, for introducing 
air into the contrast media bottle 40, for purposes which will be 
hereinafter described. Alternatively, a non-vented tubing spike tip 3a may 
be provided in the top end of the first length of tubing 2, as illustrated 
in FIG. 2. The top port of a top stopcock 9, which may be a 3-way 
stopcock, is attached to the opposite end of the first length of tubing 2 
and includes a side port 12, having a luer lock flange 6, and a knob or 
grip 10, for opening and closing the first length of tubing 2 to 
facilitate a flow of contrast media from the contrast media bottle 40. A 
stopcock luer lock 11 facilitates attachment of the top stopcock 9 to one 
end of a second length of tubing 2a. The stopcock luer lock 1 is 
conventional in design and includes a luer lock flange 6, secured to one 
end of the second length of tubing 2a, and a luer lock cap 7 attached to 
the bottom port of the top stopcock 9. The luer lock flange 6 is designed 
to engage corresponding cap threads 7a, provided in the companion luer 
lock cap 7, to removably attach one end of the second length of tubing 2a 
to the bottom port of the top stopcock 9, for purposes which will also be 
hereinafter further described. In another preferred embodiment a top check 
valve 15, a typical design of which is detailed in FIG. 3, is also 
provided in the second length of tubing 2a below the top stopcock 9, to 
prevent upward, reverse or reflux flow of contrast media through the 
second length of tubing 2a and first length of tubing 2, and possible 
contamination of the contrast media, as further hereinafter described. 
The second length of tubing 2a further receives a bottom check valve 22 and 
the opposite end of the second length of tubing 2a terminates on the top 
port of a bottom stopcock 20, which is identical in design to the top 
stopcock 9. A third length of tubing 2b extends from attachment to the 
bottom port of the bottom stopcock 20 to a luer lock cap 7 for connection 
to the corresponding luer lock flange (not illustrated) mounted on a 
conventional manifold (not illustrated), but fully described in my 
copending U.S. Patent Application, described above. As illustrated in FIG. 
3, both the top check valve 15 and bottom check valve 22 may include a 
pair of top and bottom nipples 18, for extending into the respective 
connecting second lengths of tubing 2a, as well as a seat 16 and a ball 
17, to allow fluid flow from top to bottom by gravity, through the 
dispensing apparatus 1, but serve to block the reflux of contrast media 
upwardly from bottom to top. The conventional manifold (not illustrated) 
is used to inject contrast media intravenously into a patient during the 
catheterization procedure, according to the knowledge of those skilled in 
the art and as described in our copending U.S. Patent Application 
described above. 
As illustrated in FIGS. 1-3 of the drawing, under circumstances where it is 
desirable to use a supply of contrast media stored in a contrast media 
bottle 40 in a catheterization procedure using the dispensing apparatus 1 
illustrated in FIG. 1, the contrast media bottle 40 is initially suspended 
from a suitable support over a supine patient (not illustrated) in 
conventional fashion. The top stopcock 9 is then closed to flow of 
contrast media and the contrast media bottle 40 is "spiked" by forcing the 
tubing spike 3 through the rubber plug 41, as illustrated. The luer lock 
cap 7 located on the extending or free end of the third length of tubing 
2b is then used to attach the free end of the third length of tubing 2b to 
the manifold (not illustrated) and the dispensing apparatus 1 is ready for 
use to selectively dispense contrast media from the contrast media bottle 
40, through the connected first length of tubing 2, top stopcock 9, second 
length of tubing 2a, top check valve 15, bottom check valve 22, bottom 
stopcock 20 and third length of tubing 2b, into the manifold (not 
illustrated) and to the patient in conventional fashion. Air may be 
removed or bled from the first length of tubing 2 and second length of 
tubing 2a by manipulating the respective grips 10 on the top stopcock 9 
and bottom stopcock 20 to the side port 12 position as deemed necessary. 
Contrast media or fluid is then allowed to flow from the contrast media 
bottle 40 by again manipulating the respective grips 10 and opening the 
top stopcock 9 and the bottom stopcock 20 to fluid flow through the first 
length of tubing 2, second length of tubing 2a and third length of tubing 
2b. 
Referring again to FIG. 1 of the drawings, if necessary, air can be 
introduced into the side port 12 of the top stopcock 9 to pressurize the 
air space in the contrast media bottle 40 and facilitate a more rapid flow 
of contrast media from the contrast media bottle 90 into the manifold (not 
illustrated) when the top stopcock 9 and bottom stopcock 20 are opened. 
Alternatively, opening of the vent 4 in the tubing spike 3 may provide 
sufficient pressure equalization to effect this rapid flow of contrast 
media. 
While the present invention has been described with the particularity set 
forth above, it will be understood that modifications will be apparent to 
those skilled in the art. Accordingly, the invention is limited only by 
the following claims.