Duodenal insert and method of use

A duodenal insert (20) comprises an elongated open-ended tube (22) having a passageway that extends from a first end (24) to a second end (26) for transporting partially digested food materials from the stomach (6) for a predetermined distance below the stomach to interrupt or reduce the intermixing of digestive fluids with the partially digested food materials. The duodenal insert is anchored within a pylorus (10) by a pair of spaced apart first and second rings (32 and 34) in a seated and sandwiched arrangement with the pylorus. Bores (38) and splits (40) are optionally disposed through the open-ended tube to provide the digestive fluids controlled access to the interior of the duodenal insert.

BACKGROUND OF THE INVENTION 
I. Field of the Invention 
The present invention relates generally to the field of medical appliances. 
More particularly, the present invention relates to a device for lining a 
portion of the alimentary canal to control contact time of bile and 
digestive enzymes with food ingested by a human or other animals. 
II. Description of the Related Art 
It is well know that digestion starts with the chewing of and introduction 
of saliva with food in the mouth. Digestion continues in the stomach with 
the introduction of acid and some enzymes. After a residence period within 
the stomach, the partially digested food materials move into the duodenum 
for the further introduction of digestive fluids from the pancreas, liver 
and other organs. The action of these digestive fluids causes the further 
break down of the partially digested food materials into an absorbable 
form by the ileum and/or villi of the small intestine. By interrupting the 
intermixing of the digestive fluids and/or limiting the residence period 
within the stomach, the partially digested food materials will not fully 
digest into particles small enough to be absorbed by the body. 
Smit in U.S. Pat. No. 4,315,509 describes insertion and removal catheters 
and intestinal tubes for restricting absorption. Particularly shown is a 
self-compressing, open-ended, balloon-like tube for implantation in and 
lining of the digestive tract. This device has a ring to keep one end of 
the tube open and a series of magnets to artificially simulate natural 
peristalsis. Anchoring of this device is accomplished by the single ring. 
However, unless the ring is surgically mounted, such as by sutures, 
staples or the like, to the wall of the stomach or any other organ within 
the alimentary canal, this device can move within the alimentary canal and 
close itself off from receiving consumed food materials. 
SUMMARY OF THE INVENTION 
In accordance with the present invention and the contemplated problems 
which have and continue to exist in this field, one of the objectives of 
this invention is to provide a duodenal insert that assists a patient in 
reducing his or her weight. 
Many people cannot resist the temptation to eat, often causing them to 
engage in a starvation routine or resort to purging. It is therefore 
another objective of the present invention to provide a duodenal insert 
that enables one to consume what is a typical amount of food for them so 
that their urge to eat is satisfied with continued weight control. 
Yet, it is another objective of the present invention enable a practitioner 
to control the amount of calories available for absorption by the body. 
Still, it is another objective of the present invention to control 
intermixing of digestive fluids discharged by the body into the duodenum 
with partially digested food materials discharged from the stomach. 
Even yet, it is another objective of the present invention to control the 
amount of time that ingested food remains in the stomach. 
This invention accomplishes the above and other objectives and overcomes 
the disadvantages of the prior art by providing a duodenal insert that is 
simple in design and construction, inexpensive to fabricate, and easy to 
use. The duodenal insert consists of an open-ended tube having a pair of 
spaced apart rings disposed at one of the ends of the tube. The level of 
intermixing of digestive fluids with partially digested food materials is 
controlled by one or more bores optionally disposed through the wall of 
the tube. Additionally, slits are optionally provided at the opposite end 
of the tube from the rings to permit additional intermixing. The duodenal 
insert can be inserted via the mouth through the esophagus and the 
stomach, and positioned within the duodenum. To anchor the duodenal 
insert, the rings are manipulated such that the rings are separately 
disposed on each side of the pyloric opening. The duodenal insert may be 
removed from the body by retracting the device in reverse order through 
the stomach, esophagus and mouth. In some instances, a practitioner can 
implant the duodenal insert surgically, which enables the duodenal insert 
to be manufactured from a more rigid material. 
It is to be understood that the phraseology and terminology employed herein 
are for the purpose of description and should not be regarded as limiting. 
As such, those skilled in the art will appreciate that the conception, 
upon which this disclosure is based, may readily be utilized as a basis 
for the designing of other structures, methods, and systems for carrying 
out the several purposes of the present invention. It is important, 
therefore, that the claims be regarded as including such equivalent 
constructions insofar as they do not depart from the spirit and scope of 
the present invention.

The reference numbers in the drawings relate to the following: 
2=esophagus 
4=mouth 
6=stomach 
8=esophageal-gastric juncture 
10=pylorus 
12=duodenum 
14=jejunum 
20=duodenal insert 
22=open-ended tube 
24=first end of open-ended tube 
26=second end of open-ended tube 
28=tube wall of open-ended tube 
30=surface 
32=first ring 
34=second ring 
36=pyloric conduit 
38=bore 
40=split 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
For a fuller understanding of the nature and desired objects of this 
invention, reference should be made to the following detailed description 
taken in connection with the accompanying drawings. Referring to the 
drawings wherein like reference numerals designate corresponding parts 
throughout the several figures, reference is made first to FIG. 1. FIG. 1 
of the drawings illustrates an upper digestive tract of a human. The 
esophagus 2 terminates at the nose or mouth 4 at its superior end and at 
the stomach 6 at its inferior end. The wall of the stomach 6 encloses a 
chamber which is characterized, in part, by the esophageal-gastric 
juncture 8, which is an opening to the esophagus 2, and the pylorus 10, 
which is an opening to the duodenum 12. The stomach 6 empties through the 
pylorus 10 into the duodenum 12. Specifically, the pylorus 10 controls 
discharge from the stomach 6 by a sphincter muscle, the pyloric sphincter, 
which enables the pylorus 10 to open wide enough to pass about an object 
which is approximately one cubic centimeter or less. Gastric contents, 
after passing into the duodenum 12, continue on into the jejunum 14 and on 
into the ileum. 
The duodenum 12 or first nine to ten inches of the small intestine is the 
only portion of the small intestine which is attached to the body. The 
remainder of the small intestine is not attached to the body, but merely 
folds freely in a sack called the mesentery, which is contained within the 
peritoneum. 
Digestion starts with the chewing of food materials in combination with the 
action of saliva and enzymes secreted in the mouth 4. Within the stomach 
6, digestion continues with the action of acids and additional enzymes 
secreted therein to produce partially digested food materials. After a 
short residence time in the stomach 6, the partially digested food moves 
further along the alimentary canal into the duodenum 12 to be intermixed 
with other digestive fluids which further digest the partially digested 
food materials to make the nutrients contained therein available for 
absorption by the villi and microvilli of the small intestine or by other 
absorptive organs of the body. 
By interrupting or reducing the intermixing of the digestive fluids made 
available in the duodenum 12, the partially digested food materials are 
not readily absorbable by the small intestine or other absorptive organs 
of the body. The partially digested food materials are then passed to the 
large intestine for elimination from the body with limited caloric 
absorption by the body. The same effect can occur if the partially 
digested food materials are moved too quickly from the stomach 6 to the 
jejunum 14 or the ileum. It takes a certain amount of time for the 
digestive fluids introduced within the duodenum 12 to break down the 
partially digested food materials into an absorbable form having a small 
particle size. Even some liquid food materials have particle sizes that 
are too large to be absorbed without sufficient intermixing of the 
digestive fluids introduced within the duodenum 12 or without sufficient 
time for the digestive fluids to act. 
Referring now to FIGS. 2 and 3, these Figures of the drawings illustrate a 
duodenal insert 20 made in accordance with the present invention. The 
duodenal insert 20 enables a practitioner to predeterminatively limit 
caloric absorption by the body by controlling the amount of digestive 
fluids introduced within the duodenum 12 which can intermix with the 
partially digested food materials and/or limiting amount of time for these 
digestive fluids to break down the partially digested food materials into 
an absorbable form. By limiting the body's ability to break down the 
partially digested food materials into an absorbable form, the 
practitioner can effectuate weight loss in a patient in a controlled 
manner. For example, if a patient has a history of being twenty percent 
(20%) overweight, it is readily apparent that the patient is consuming 
and/or absorbing too many calories from food. Accordingly, the 
practitioner can fit the patient with a duodenal insert 20 which allows 
only about eighty percent (80%) of the available calories from the food to 
be absorbable by the body. 
As particularly shown in FIG. 2, the duodenal insert 20 is disposed within 
the duodenum 12 and anchored within the pylorus 10. With continued 
reference to FIGS. 2 and 3, the duodenal insert 20 comprises an elongated 
open-ended tube 22 having, a first end 24, a second end 26 and a tube wall 
28 extending between the first an second ends 24 and 26. Within the 
open-ended tube 22 is a passageway that extends from the first end 24 to 
the second end 26 for transporting the partially digested food materials 
from the stomach 6 a predetermined distance below the stomach 6. 
Preferably, the passageway has a smooth and unobstructed surface 30 to 
enable the partially digested food materials to be squeezed through the 
open-ended tube 22 by natural peristalsis action of the alimentary canal. 
The duodenal insert 20 is preferably flexible to enable it to conform to 
the curves and contractions of the stomach 6, the duodenum 10 and other 
organs of the alimentary canal. 
As previously mentioned, the duodenal insert 20 is anchored, preferably 
removably anchored, within the pylorus 10. The duodenal insert 20 may be 
implanted orally or surgically. If the duodenal insert 20 is implanted 
surgically, the duodenal insert 20 to be manufactured from a more rigid 
material. Since the duodenum 12 is attached to the body, the duodenal 
insert 20 can be manufactured of a relatively flexible material. At the 
first end 24 of the open-ended tube 22, is a first ring 32 which is 
attached around its circumference to the first end 24. The first ring 32 
holds the first end 24 of the open-ended tube 22 open to receive the 
partially digested food materials from the stomach 6. It is preferred for 
the first ring 32 to be made of a collapsible, yet resilient material. 
Spaced a predetermined distance from the first ring 32 is a second ring 
34. The second ring 34 is attached around its circumference to the 
open-ended tube 22 and holds the open-ended tube 22 open at that point to 
receive the partially digested food materials received by the first ring 
32. It is likewise preferred for the second ring 34 to be made of a 
collapsible, yet resilient material. The open-ended tube 22 has a flexible 
pyloric conduit 36 extending from the first ring 32 to the second ring 34. 
In operation, the duodenal insert 20 is anchored by collapsing the second 
ring 34 and directing it through the pylorus 10. Once through the pylorus 
10, the second ring 34 is permitted to return to its annular shape and 
seat adjacent the pylorus 10 within the duodenum 12. Preferably, the 
distance between the first and second rings 32 and 34, or in other words, 
the length of the pyloric conduit 36, is sufficient to permit the pyloric 
conduit 36 to extend through the pylorus 10 and allow the first and second 
rings 32 and 34 to encircle and to seat adjacent the pylorus 10 within the 
stomach 6 and within the duodenum 12, respectively. In this manner, the 
pylorus 10 is sandwiched between the first and second rings 32 and 34, and 
the pyloric sphincter engages the pyloric conduit 36 to anchor the 
duodenal insert 20 within the pylorus 10. Clearly, the first and second 
rings 32 and 34 should be larger than the opening of the pylorus 10. 
Additionally, the second ring 34 must be able to pass through the pylorus 
10 while in a collapsed state without damaging the tissue of the pylorus 
10. Depending either upon the length or the flexibility of the material of 
the pyloric conduit 36, or a combination of both, the pylorus 10 can be 
kept open to varying degrees or be permitted to naturally close. By 
controlling the opening of the pylorus 10, the practitioner can control 
the time food materials are permitted to remain within the stomach 6, 
thereby predetermitively limiting the level of break down of partially 
digested food materials for absorption. To implant the duodenal insert 20 
orally, the duodenal insert 20 is collapsed, preferably along a 
longitudinal axis of the duodenal insert 20 extending from the first end 
24 to the second end 26, and inserted through the mouth 4, the esophagus 2 
and the stomach 6, anchored within the pylorus 10 and extended into the 
duodenum 12. 
By anchoring the duodenal insert 20 within the pylorus 10, the digestive 
fluids made available by the body in the duodenum 12 for intermixing with 
the partially digested food materials exiting the stomach 6 can be 
interrupted or reduced. Essentially no or very little intermixing occurs 
within the duodenal insert 20 when the tube wall 28 is fabricated with a 
nonpermeable material. With continuing reference to FIG. 3, bores 38 are 
shown disposed through the tube wall 28 to provide the digestive fluids 
controlled access to the interior of the duodenal insert 20. This feature 
provides the practitioner with the ability to control the intermixing of 
digestive fluids discharged by the body into the duodenum 12 with the 
partially digested food materials contained within the duodenal insert 20. 
The amount of digestive fluids entering the duodenal insert 20 is 
controlled by the size and number of the bores 38 and the location of the 
bores 38 with respect to the ducts delivering the digestive fluids to the 
duodenum 12. 
Also shown in FIGS. 2 and 3 are splits 40 disposed along the tube wall 28, 
which provide controlled access to the interior of the duodenal insert 20. 
As with the bores 38, the splits 40 provide the practitioner with the 
ability to control the intermixing of digestive fluids discharged by the 
body into the duodenum 12 with the partially digested food materials 
contained within the duodenal insert 20. The amount of digestive fluids 
entering the duodenal insert 20 is controlled by the length, width and 
number of the splits 40 and, likewise, the location of the splits 40 with 
respect to the ducts delivering the digestive fluids to the duodenum 12. 
The splits 40 may be located anywhere along the tube wall 28. With the 
embodiments shown in FIGS. 2 and 3, the splits 40 extend from the second 
end 26 for a predetermined distance toward the first end 24. 
The materials of construction of the duodenal insert 20 are not highly 
critical so long as they are compatible with the body tissues and fluids 
involved. Such useful materials are, for example, dacron, latex and 
silicone, but these materials are illustrative only and are non-exclusive. 
In an alternate embodiment of the present invention, the duodenal insert 
20 can be fabricated from materials which biodegrade in the alimentary 
canal after preselected periods of time. In this manner, the practitioner 
can select the appropriate biodegradation time so that the duodenal insert 
20 can be removed from the alimentary canal by normal processes at such 
time as it has achieved the desired physiological result. Yet, in another 
embodiment of the present invention, the tube wall 28 can be manufactured 
from a porous material which provides controlled intermixing of digestive 
fluids discharged by the body into the duodenum 12 with the partially 
digested food materials contained within the duodenal insert 20. As with 
the bores 38, amount of digestive fluids entering the duodenal insert 20 
is controlled by the size and number of the pores (not shown). 
With respect to the above description then, it is to be realized that the 
optimum dimensional relationships for the parts of the invention, to 
include variations in size, materials, shape, form, function and manner of 
operation, assembly and use, are deemed readily apparent and obvious to 
one skilled in the art, and all equivalent relationships to those 
illustrated in the drawings and described in the specification are 
intended to be encompassed by the present invention. 
Therefore, the foregoing is considered as illustrative only of the 
principles of the invention. Further, various modifications may be made of 
the invention without departing from the scope thereof and it is desired, 
therefore, that only such limitations shall be placed thereon as are 
imposed by the prior art and which are set forth in the appended claims.