WO2004098404A2 - A system for detecting enlarged lymph nodes - Google Patents

Abstract

An apparatus for simulating conditions of variable stages of oral cancel includes a head form. The head form comprises rigid structure elements to represent reference points for lymph nodes. These rigid structures include the ears, neck and jaw. Inflatable elements represent the lymph nodes, which can be independently and variably inflated to a desired size and hardness using a computer-controlled pump system.

Description

A System For Detecting Enlarged Lymph Nodes

Field of Invention

[01] This International Application claims the benefit of U.S. Provisional

Application No. 60/467,559 filed on May 5, 2003.

[02] Early detection of oral cancer may increase the rate of survival for patients by fifty percent. The present invention relates to a system for modeling the changes that occur in lymph nodes resulting from oral cancer development and metastasis. This system is designed to provide health care professionals with a non-invasive approach to the detection of oral cancer, based on the size of the affected lymph node.

Background of Art

[03] Carcinomas are difficult to detect in patients. In head and neck carcinoma, detection is difficult because palpitation requires the manipulation of skin, muscle, and flesh in order to expose the lymph nodes. Once found, these nodes must then be evaluated for cancer, taking into account that the nodules may be enlarged due to other ailments. Lymph nodes have different consistencies depending on existing conditions of the patient, and will likely exhibit lateral asymmetry in size and texture when cancer is present. The practitioner must be able to evaluate all of these factors and make a sound decision about the presence of oral cancer.

[04] Oral cancer accounts for about 3.6% of all cancer patients. However, the incidence of death among this population is greater than brain, cervical, liver, testes, kidney, ovary, and skin cancers. Oral cancer claims an average of about 9,000 lives in the U.S. every year. Post diagnosis, about 60% of oral cancer patients elect surgery driving the health care costs of oral cancer to about $3 million a year. Unfortunately, the five- year survival rate for oral cancer patients is only about 50%. Like other cancers, early detection of oral cancer increases the chance of survival for patients. It is expected that survival following early detection could be increased by nearly 50%. However, many people do not get tested for oral cancer, and misdiagnosis is common, which has led to the dismal statistic that only about 35% of oral cancer patients are diagnosed in early stages of the disease

[05] Currently, comprehensive evaluative and instructional devices do not exist for the detection and the instruction on how to detect an enlarged lymph node, which serves as an indicator of oral cancers. The present invention remedies this deficiency in the field by providing an apparatus capable of simulating different stages of lymph node size to assist patients and health care providers in the diagnosis of oral cancers and to facilitate early detection. The invention also relates to the manufacture of such a system and use thereof.

Summary of the Invention

[06] The present invention is directed to a model system for detecting the presence of cancer of the head and neck. The model comprises anatomical features of the head and neck, including soft and malleable tissues, a variable size lymph node system activated by a set of pumps, and a computer interface. A lymph node of the present invention is simulated using a series of balloon catheters that may be independently controlled by a computer indicating the size and density, simulating location and progression of carcinomas. This system provides capability for instructing and educating health care providers and/or patients in the detection of oral cancers.

Brief Description of the Drawings

[07] An exemplary embodiment of the invention will be described below, with reference to the appended drawings in which: [08] Fig. 1 illustrates a hollow plastic mannequin mold for forming a head model according to an embodiment of the invention;

[09] Fig. 2 illustrates a head model of solid silicone according to an embodiment of the invention;

[10] Fig. 3 illustrates a jaw bone using a metallic hanger and clay according to an embodiment of the invention;

[11] Fig. 4 illustrates four balloon catheters on each side of modeled trachea to model a sublingual chain of lymph nodes attached to the trachea according to an embodiment of the invention;

[12] Fig. 5 illustrates a ring clamp inside an inverted head mold for holding the jaw and neck model during casting of the head model according to an embodiment;

[13] Fig. 6 illustrates silicon material mixed with a catalyst and colorant according to an embodiment of the invention;

[14] Fig. 7 illustrates a syringe pump with individual control for each of the syringes for a pump system according to an embodiment of the invention;

[15] Fig. 8 illustrates a picture of the motor/drive shaft interface to activate the syringes according to an embodiment of the invention;

[16] Fig. 9 illustrates a relay wiring schematic for the ULN interface chip to control the syringes according to an embodiment of the invention;

[17] Fig. 10 illustrates chip wiring schematic for the ULN interface chip to control the syringes according to an embodiment of the invention;

[18] Fig. 11 illustrates an intuitive graphical user interface;

[19] Fig. 12 illustrates the data acquisition card according to a preferred embodiment; [20] Fig. 13 illustrates an integrated head model, pump and control system according to an embodiment;

[21] Fig. 14 illustrates a region of the body where the nodes are simulated according to an embodiment of the invention;

[22] Fig. 15 illustrates a schematic system view of an embodiment of the invention;

[23] Fig. 16 illustrates a schematic of the computer to pump system interface according to an embodiment.

Description of Exemplary Embodiment

[24] Detecting oral cancer generally requires a trained health care professional, typically a physician, dentist, nurse or dental hygienist, to palpitate regions of the head and neck. A comprehensive head and neck examination includes the manipulation of the oral soft tissues, tongue and other muscle groups, allowing the health care provider to feel the lymph node. However, a swollen node may be due to a common cold or other ailment inflicting an inflammatory response of the lymph system. The medical professional performing the assessment must be able to distinguish between different size and consistency of a swollen lymph node, and be able to differentiate abnormal versus normal conditions. Swollen lymph nodes, located behind the ears, under the tongue, and down the sides of the neck, are only about 5 to about 10 mm in diameter, thereby making detection difficult. In contrast, healthy lymph nodes are often undetectable. Currently, improving the detection of an oral cancer and/or enlarged lymph node requires a medical professional (personnel) to practice the described palpitation method. However, no realistic model is available for education, training and practice in the palpitation of lymph nodes. Although the evaluation procedure can be described, this method remains inefficient and ineffective, particularly because oral cancers, and more specifically enlarged lymph nodes are difficult to assess and not commonly found in the general population. Because of this deficiency in the art, most medical personnel lack first-hand knowledge of precisely the feel of an enlarged node. This lack of knowledge is one of the major reasons that an oral cancer often goes undetected in early stages of development.

[25] Referring to the schematic of Figure 15, the system of the present invention includes primarily three sub-systems, 1) the model of the head 1, 2) a system of pumps P1-P4 for independently inflating catheters C1-C4 to simulate lymph nodes, and 3) a computer or controller 2 to control inflating and deflating the catheters to different levels. A graphical user interface, such as shown in Fig. 11, facilitates the user's ability to modulate the size of the lymph nodes. Though only four nodes are illustrated in Fig. 15, additional lymph nodes can be added. In an exemplary embodiment described herein, eight nodes were simulated in the submandibular and sublingual areas of the model.

[26] The anatomical portion preferably has a realistic appearance and texture, meaning the model system should bear strong resemblances in physical characteristic to the anatomy of the human head and neck. In an exemplary embodiment as illustrated by Fig. 2, the model of the head is cast out of a silicon. A mold to form the head model is shown in Fig. 1. Silicones having a lower density are contemplated such as Dragon Skin produced by Smooth-On. The important feature when determining the type of material for the anatomical portion(s) is malleability and resemblance in texture to the human skin. A colorant may be added to the silicone to simulate skin tone as shown in Fig. 6.

[27] A plaster lower jaw (mandible) and a simulated trachea were inserted during the casting of the head. An exemplary assembly is shown in Fig. 5. These features represent and simulate the mandible, vertebrae and surrounding regions. Alternatively, the internal structures are constructed from a combination of metallic frames and malleable materials, including polymeric material, gortex and/or ceramic. In a non-limiting example, the jawbone is fashioned from a metal material and surrounded by clay to create the correct thickness and hardness, as shown in Fig. 3. A flexible metal rod is used for the neck vertebrae to permit realistic neck flexibility. The catheters may be attached to the angle and lingual (inner) surface of the mandible for better stability.

[28] In an alternative embodiment, the model comprises a portion of a head situated between and below the ears. This embodiment may be preferred in instances requiring reduced manufacturing costs. The portion of the head, as compared to a complete head structure, should include all possible enlarged lymph nodes in oral cancer detection. The model further includes reference points such as, an ear and/or tongue. Other materials contemplated for the construction of this part of the model include gortex, and ceramic.

[29] In the exemplary embodiment, balloon catheters simulate the lymph nodes, which are embedded in the silicon material. However, any inflatable medium of appropriate size and shape may be used. The catheters simulate the sublingual and submandibular chains of lymph nodes running under the chin, under the tongue and/or down the neck. The relevant portions of the body for oral cancer detection is shown in Fig. 14. The simulating nodes must meet requirements of hardness, rigidity, fixedness and range from about 1 to about 10 mm, or about 2 to about 10 mm, or about 3 to about 10 mm, or about 4 to about 10 mm, or about 5 to about 10 mm in diameter. The simulated nodes are preferably adjustable in size and allow for graded input and output. In the non- limiting example discussed herein, the catheters were strategically placed inside the model at the locations of a total of eight prominent nodes, four on each side of the head and neck, as shown in Fig. 4. Through the use of a saline solution or gel or air, the balloons are inflated to different sizes to simulate progressing severity of oral cancer. Preferably, an abiotic agent is added to any fluid to prevent fungal and bacterial build up in the pump used to fill the catheters.

[30] A controlled pressurized pump system inflates and deflates the catheters. One mechanism to achieve the controlled pressurized pump system uses a syringe pump for each catheter. Alternatively, a centrally controlled pump system may be used. In the exemplary embodiment, each syringe is controlled by a 24 volt, 72 RPM Pittman motor (Fig. 8), which is directed by a computer interface, such as a computer interface written in Lab View. In response to a control signal, the motor runs clockwise (inflates) or counterclockwise (deflates) as specified by the computer interface. The motors are connected to a 10 % inch threaded shafts, which drives the cylinders up and down the shaft. The cylinders are attached to metal brackets that hold the plungers of the syringes. When the motors are activated, the plunger is either pushed in or pulled out, causing air (or other medium) to be infused or withdrawn, respectively, from the balloon catheters. The exemplary pump system is shown in Fig. 7. Injection of different amounts and types of media can vary the size and feel of the modeled lymph nodes. For example, water, saline, silicone and oil may be used.

[31] Fig. 16 illustrates the wiring for controlling the motors to inflate or deflate the catheters. For purposes of illustration, only two motors Ml and M2 are shown, through respective contacts with relays RL1, RL2, and indicator LED's. The entire wiring of the motors includes 16 relays, wired as eight banks of two relays. Each relay bank is located to the side of its respective motor. Relays are electromechanical switches, which serve as contact points for multiple contacts. When a voltage is applied, an electromagnet inside of the relay is activated creating a current. The two relays for each motor are wired so that a proper signal will cause the motor to rotate clockwise or counter-clockwise depending on the desires of the user. A ULN 2003 chip connects each motor via a relay (Figs. 9-10). The chip includes an input and output end. The input ends are connected to two 10-conductor control cables, while the other end plugs into a 6025E Data Acquisition (DAQ) Card (Fig. 12) for the computer interface. The output end is connected to each motor through two different wires to provide the forward and reverse driving functions. The chip is connected to the power supply and grounded. Red LED's LEDR1, LEDR2 and green LED's LEDG1, LEDG2 respectively indicate when a pump is withdrawing air or fluid and infusing air or fluid to the balloon catheters. However, when the power is removed the collapsing electric field produces a reverse current, which can damage sensitive electronic parts and wiring. For this reason, diodes are built into the relays to protect the wiring and circuitry. Each relay connects the motor, the power source, a ULN 2003 chip, and the red and green LED's. Fig. 13 illustrates an assembly of the control system and head model.

[32] The power source for the pump supplies 24 volts with a maximum current of 3.6 amps. A 2 amp fuse is connected between the power source and pump wiring to provide an emergency shut off in case of a power spike. The fuse is wired to a blue LED to indicate when the pump is powered. The power source connects to the motors via the relays. A muffin fan and cooling holes provide airflow and cooling.

[33] A computer system controls the balloon catheters and facilitates operation of the model. For example, a computer interface program written in Lab View allows the operator to select individual nodes and a control the size of the oral cancer they wish to simulate. The computer activates the pump system, which either inflates or deflates the catheters according to the operator's specifications.

[34] For instructional purposes, the ability of a computer to easily recreate previous settings from stored data is highly useful. For example, standardized scenarios can be established. The computer interface in the preferred embodiment was programmed in Lab View from National Instruments (NI), however, any suitable computer interface program will suffice. The controlling mechanism employed was a National Instruments Model 6025E card, which included the necessary channels for controlling the multiple nodes. The card connects to the computer using a PCI-bus interface. To manipulate the card, virtual channels were created using Measurements and Automation. Channels are imported into the computer interface program. To activate a particular pump, the appropriate channel on the DAQ card is activated for a set amount of time. Alternative data acquisition cards and interconnection medium may also be used.

[35] The model system of the present invention allows medical professionals to practice testing for oral cancer in a novel fashion. In addition, the technology used in this exemplary embodiment is readily transferable to other parts of the body. In addition to basic requirements discussed above, alternative embodiments can be made to reduce the cost of the system or improve usability. For example, in an alternative embodiment, the type of material for forming the head model should be considered in view of the type of medium used to fill the catheters. For example, use of a silicon material having a high density for the head model can be balanced with relatively denser materials for inflating the catheters. As an alternative embodiment, as further features of the invention, in order to accurately inflate the catheters, pressure sensors and cut-off valves can be installed on every line. Feedback from the pressure sensor to the computer/controller can automatically facilitate how fluids are introduced into the simulated lymph nodes. Although the above description relates to preferred embodiments, one skilled in the art would recognize that modifications can be made which fall within the scope and spirit of the invention as described in the appended claims.

Claims

We claim:

1. A system for detecting the presence of an oral cancer comprising: a malleable head form further including a plurality of inflatable elements; a pump apparatus performing one of inflating and deflating the plurality of inflatable elements; and a control system controlling the pump apparatus.

2. The system of claim 1, wherein the pump apparatus independently inflates and deflates the plurality of inflatable elements.

3. The system of claim 1 , wherein the malleable head form further includes rigid structures representing at least one of a jaw bone and a neck vertebrae.

4. The system of claim 1, wherein the plurality of inflatable elements have at least one of a cylindrical and spherical form.

5. The system of claim 4, wherein each of the plurality of inflatable elements has a diameter in the range of about 1 to about 10 mm.

6. The system of claim 3, wherein the malleable head form further includes a malleable structure representing at least one of a tongue and a trachea.

7. The system of claim 2, wherein the pump system includes a plurality of syringes attached to a plurality of motors, each of said syringes introducing and withdrawing at least one fluid into respective ones of the plurality of inflatable elements.

8. The system of claim 7, wherein the pump system further includes a plurality of sensors to determine a pressure condition for respective ones of the plurality of inflatable elements, the plurality of sensors providing output to the control system to control the pump apparatus automatically.

9. The system of claim 7, wherein the control system operates the pump apparatus to inflate at least one of the plurality of inflatable elements to a predetermined size.

10. The system of claim 1, wherein said control system includes a memory for storing data corresponding to previously set conditions for inflating at least one of the plurality of inflatable elements to a predetermined size, and controls the pump apparatus to inflate and deflate the at least one inflatable element in accordance with the data.

11. A method of detecting conditions of oral cancer comprising: providing a malleable head form; detecting simulated lymph nodes in the malleable head form.

12. The method of claim 11 further comprising: changing a physical condition of the simulated lymph node.

13. The method of claim 12, wherein the simulated lymph node comprises an inflatable element and changing the condition of the simulated lymph node comprises at least one of inflating and deflating the inflatable element.

14. A method for manufacturing a system for detecting cancer comprising: a malleable form representing a body part; and placing a plurality of simulated lymph nodes within the malleable form, said simulated lymph nodes capable of varying in a physical characteristic.

15. A method of claim 14, wherein the plurality of simulated lymph nodes comprises inflatable elements.

16. A method of claim 15 further comprising: connecting at least one of the plurality of simulated lymph nodes to a pump apparatus to perform one of inflating and deflating of at least one of the plurality of simulated lymph nodes.

17. A system for detecting the presence of a cancer comprising: a malleable form representing a body part; one or more simulated lymph nodes deposed within the malleable form; and a control apparatus changing a physical characteristic of at least one of the simulated lymph nodes.