DIAGNOSTIC TAMPON AND THE USE THEREOF FOR COLLECTING CELLULAR MATERIAL
United States Patent 3850160
A diagnostic tampon comprising a supporting body, the surface of which is covered with a film of polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose. The tampon is particularly adapted for collecting cellular material including bacterial, fungal and parasitic elements, from body cavities, in particular the vaginal cavity, for subsequent examination.
US Patent References:
Catamenial plug
Richardson - October 1933 - 1932383
TAMPON OR SIMILAR SANITARY NAPKIN CONTAINING VITAMIN A
Waterbury - July 1970 - 3521637
TAMPON AND PROCESS AND APPARATUS FOR MAKING THE SAME
Croon - February 1973 - 3716430
Catamenial plug
Richardson - October 1933 - 1932383
TAMPON OR SIMILAR SANITARY NAPKIN CONTAINING VITAMIN A
Waterbury - July 1970 - 3521637
TAMPON AND PROCESS AND APPARATUS FOR MAKING THE SAME
Croon - February 1973 - 3716430
Application Number:
05/440166
Publication Date:
11/26/1974
Filing Date:
02/06/1974
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
604/57
International Classes:
A61B10/00; A61F13/20; G01N33/52; A61F13/20
Field of Search:
128/2B,263,270,285
Primary Examiner:
Medbery, Aldrich F.
Attorney, Agent or Firm:
Bacon & Thomas
Parent Case Data:
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part of application, Ser. No. 332,718, filed Feb. 15, l973 and now abandoned.
Claims:
What is claimed is
1. A tampon including a means for obtaining cell specimens for diagnosis which comprises a supporting body that is flexible, appropriately shaped and stiff enough to be inserted into a body cavity, said supporting body having a covering portion comprising an external film of polycarbonate or a porous sheet composed of biologically inert mixed esters of cellulose secured to the surface of said supporting body.
2. A vaginal tampon for obtaining cell specimens for diagnosis which comprises a cylindrical shaped, supporting body having a film of polycarbonate secured to the surface thereof.
3. A method for collecting and examining cellular material from the vaginal cavity which comprises:
4. The method of claim 3 wherein after step (d) the film is dissolved with an inert solvent before examining the stained cellular material on the slide.
5. The method of claim 4 wherein the solvent is selected from the group consisting of bromoform, chloroform, ethyl dichloride, methylene chloride, and 1,1,2-trichloroethane.
6. The method of claim 5 wherein the solvent is chloroform.
1. A tampon including a means for obtaining cell specimens for diagnosis which comprises a supporting body that is flexible, appropriately shaped and stiff enough to be inserted into a body cavity, said supporting body having a covering portion comprising an external film of polycarbonate or a porous sheet composed of biologically inert mixed esters of cellulose secured to the surface of said supporting body.
2. A vaginal tampon for obtaining cell specimens for diagnosis which comprises a cylindrical shaped, supporting body having a film of polycarbonate secured to the surface thereof.
3. A method for collecting and examining cellular material from the vaginal cavity which comprises:
4. The method of claim 3 wherein after step (d) the film is dissolved with an inert solvent before examining the stained cellular material on the slide.
5. The method of claim 4 wherein the solvent is selected from the group consisting of bromoform, chloroform, ethyl dichloride, methylene chloride, and 1,1,2-trichloroethane.
6. The method of claim 5 wherein the solvent is chloroform.
Description:
BACKGROUND OF THE INVENTION
1. Field Of The Invention
The present invention relates to a diagnostic tampon for collecting cellular material, including bacterial, fungal and parasitic elements, from body cavities, in particular the vaginal cavity, wherein the tampon surface is covered with a film of polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose. The tampon of the present invention is particularly adapted for the mass screening and detection of cancer of the pelvic region, in particular the female genital tract. It is of further use in detecting bacterial, fungal or parasitic elements in the female genital tract. The invention also relates to a method for collecting cellular material from the vaginal cavity.
2. Description Of The Prior Art
In recent years the collection of cellular specimens from the human vaginal tract has provided an effective menans for detecting early cancer of the cervix. The cellular material thus obtained is applied, as a cervical vaginal smear, onto a microscope slide and appropriately fixed, stained, and examined. This procedure broadly describes the Papanicolaou Test, popularly known as the Pap Test. The Papanicolaou (cytological) smear is generally obtained by the physician in the office by inserting a speculum into the vagina without lubricant, thereby exposing the cervix. The surface of the external os is then scraped thoroughly and the detritus placed on a glass slide. A second specimen is obtained from the posterior fornix and placed on another glass slide. The two slides are then appropriately treated and sent to the laboratory for cytological study. Unfortunately, for reasons of modesty, many women are reluctant to present themselves periodically for gynecological examination, which usually involves an office visit which, of course, requires further effort by the patient. Many women, particularly those living in remote areas such as rural areas, also find it difficult to present themselves periodically for such examinations. Consequently, there has been a definite need for a simple means for collecting cellular material and the like from the female genital tract, which would be especially suitable for mass screening techniques. It would be desirable to be able to utilize a simple method which could be effectively employed by the patient, preferably at home, without the need for any professional assistance. Towards a means of achieving this aim, there have been proposals to use tampon-like devices adapted for cancer detection. Two of such devices are described in U.S. Pat. No. 2,905,169 and U.S. Pat. No. Re. 24,666.
In one of the prior art techniques, a cotton fiber tampon is covered by a jacket made out of a closely woven sheercloth manufactured from a non-absorbent continuous filament yarn such as nylon. This jacket holds whatever cells are collected from the body cavity on its surface and because the cloth of the jacket is not absorbent the cells are not dehydrated. The collected cells are evenly smeared onto a microscopic slide by rotating the tampon is contact with the slide. The other prior art method involves the use of a tampon manufactured from a nylon or other synthetic sponge, which softens and swells as it adsorbs the bodily secretions.
The prior art devices suffer from various disadvantages, particularly when the collected cells are to be examined a considerable time after they are collected. There is thus a particular need for a device whereby the cellular materials can be collected unassistedly by the patient and thereafter forwarded, either directly or by mail or parcel post, to the examining laboratory or treating physician. Such a procedure is particularly suitable for geographical areas having a shortage of physicians and cytopathological laboratories, and such a device would be extremely suitable for large scale examinations where a considerable number of such specimens could be examined at one time.
The present invention now provides a suitable diagnostic tampon which can be used directly by the patient to collect cellular material from various body cavities, in particular the vaginal cavity. The diagnostic tampon of this invention can be given to the patient directly by the personal physician or mailed to her by a cytopathological laboratory at his request. It is also particularly adapted for dispensation by pharmacies upon a doctor's prescription.
SUMMARY OF THE INVENTION
The present invention provides a diagnostic tampon for obtaining cell specimens, including bacterial and fungal microorganisms and the like, for diagnosis comprising a supporting body which is flexible and stiff enough to be inserted into a body cavity wherein the surface of the supporting body is covered with either a film of polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose.
The present invention also describes a vaginal diagnostic tampon for obtaining cell specimens from the vaginal cavity comprising a cylindrical shaped supporting body having a film of polycarbonate secured to the surface of the supporting body.
It is also an object of this invention to provide a method for collecting cellular material from the vaginal cavity comprising:
a. inserting into the vaginal cavity a tampon where the tampon surface is covered with a film of polycarbonate;
b. withdrawing the tampon;
c. removing the film from the tampon and placing it on a slide;
d. fixing and staining the cellular material on the film; and thereafter
e. examining the stained cellular material.
In the preferred method of collecting and examining the cellular material, after the cellular material on the film is fixed and stained, the film is dissolved with an inert solvent, thereby leaving only the cellular material on the slide.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of the herein described tampon, the surface of which is substantially completely covered with polycarbonate film.
FIG. 2 is a perspective view of a modified form of the tampon on FIG. 1 showing only a portion of the tampon covered by the film.
DETAILED DESCRIPTION OF THE INVENTION
The tampon of this invention, as shown in the accompanying figures, is of a conventional type exemplified by the catamenial devices that are widely used. Referring to the figures, there is shown in FIG. 1 a tampon 10 which comprises a supporting body 13 similar in size and shape to the type generally used for catamenial tampons. This body is of a size and of a material sufficiently flexible and stiff enough to be inserted into a body cavity. For use in the vaginal cavity, the tamon is preferably about 21/4 inches long with a circumference of about 2 inches. The supporting body can be prepared from various materials, such as cotton, cellulose, nylon and the like.
Covering the supporting body 13 is a polycarbonate film or a porous sheet composed of pure, biologically inert mixed esters of cellulose 12. There is also attached at the end of the supporting body a removal string 11. Both the string and the film can be attached to the supporting body by conventional fastenings, such as stitching and the like.
FIG. 2 is a modified form of the preferred tampon shown in FIG. 1, having only part of the supporting body 13 covered by the film. FIG. 2 thus shows a tampon 14 comprising a supporting body 13 partially covered by a polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose 16. Attached to the end of supporting body 13 is a removal string 11. While the film is shown in the figures as having a smooth surface, the diagnostic tampon can also be manufactured so that the outer film covering has a corrugated surface, thereby presenting a larger film surface area to the body cavity.
Although either a polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose can be used on the surface of the tampon, the polycarbonate film is especially preferred. As is well known, the polycarbonate used to prepare such films are the conventional, thermoplastic, linear polyesters of carbonic acid derived from the polymeric condensation of bisphenols with one or more phosgenes, such as phosgene or its derivatives. A particularly preferred polycarbonate film is that commercially available under the Trademark "Nucleopore", a membrane filter available from the Nucleopore Corporation, Pleasanton, California 94566. This particular plycarbonate film contains a large number of straight-through pores, and it is understood that this film is prepared by treating conventional polycarbonate films according to the method disclosed in U.S. Pat. No. 3,303,085. The commercially available material is available in pore sizes of 20A to 8 microns and can contain 4×10 5 pores/cm 2 of film. A pore size of 5. 0-8. 0μ (microns) is especially preferred. Nevertheless, other polycarbonate films can be used as well, even the conventional polycarbonate films that lack such pores. While the thickness of the film is not critical, a thickness of 8-13 microns is preferred, with a film thickness of 10mμ. being especially preferred.
Another preferred tampon covering is a porous sheet composed of pure, biologically inert mixed esters of cellulose. Typical mixed esters include cellulose acetate propionate and cellulose acetate butyrate. Other mixed cellulose esters can be prepared containing other combinations of lower alkanoate groups, especially low alkanoate groups containing less than 5 carbon atoms. Alternatively, the porous sheet of mixed esters of cellulose can be derived from the mixture of the pure, simple cellulose lower alkanoate esters, such as mixtures of cellulose acetate, cellulose propionate, cellulose butyrate and the like. Cellulose nitrate can also be added to such mixtures. U.S. Pat. No. 2,926,104 discloses a convenient method of preparing microporous cellulose ester films.
An especially preferred series of membranes derived from the mixed esters of cellulose are the commercially available MF-Millipore filters available from the Millipore Corporation, Bedford, Massachusetts 01730. These filters come in about 12 distinct sizes containing pores ranging from 8 microns to 25 millimicrons and are microporous screens containing millions of pores/cm 2 of surface area.
The tampon of the invention can be inserted into the desired body cavity by means of typical tampon applicators, such as for example those disclosed in U.S. Pat. No. 1,926,900 and U.S. Pat. No. 3,101,713.
The diagnostic tampon of this invention can be used to collect exfoliated cells originating in the epithelial, mesothelial and endothelial tissue and also foreign elements such as bacterial or fungal microorganisms and the like. Accordingly, as used herein the expression "cellular material" should be understood to include all of such elements.
It will therefore be seen that the tampon of this invention is particularly adapted for a wide variety of diagnostic purposes. First and foremost it is especially suitable for use in obtaining a cervical vaginal smear for diagnosis in the Pap test. In addition, it can be used to collect pathological bacteria such as Neisseria gonorrhoeae, the causative organism of gonorrhea, as well as pathogenic fungal parasites, such as Candida albicans, the causative agent of Moniliasis, which can be particularly troublesome in the vaginal tract. Other bacterial infections that can be diagnosed include Trichomonas vaginalis and Hemophilus vaginalis, as well as various gonococsal, spirochetal, staphylococcal and streptococcal infections.
For vaginal use in the Pap Test, the tampon is inserted into the vagina to the point of contact with the cervix. For the Pap test, the diagnostic tampon shown in FIG. 1 is preferred since the end of the tampon is covered with the film thereby facilitating collection of cells from the external cervical os. The tampon is left in place several minutes while the patient is in an erect or semi-erect position. The tampon is then withdrawn, utilizing the attached removal string and immediately thereafter placed in a fixative. There are numerous satisfactory fixatives for use in the Pap smear which are well-known to those skilled in the art. Where it is intended that the tampon is to be sent elsewhere for examination, the tampon is inserted into an appropriate mailer which releases the fixative upon enclosing. The patient's identification and history generally accompany the specimen to the laboratory.
At the laboratory, the polycarbonate film covering the tampon is removed and divided into two portions, each of which is placed on a glass slide. The film can easily be removed from the supporting body of the tampon by placing the tampon in an upright position, such as on a spindle, and then with a surgical scapel bisecting the film lengthwise, i.e. vertically, and then cutting the bottom of the film, which remains attached to the supporting body, thereby providing two film sections having rounded edges at one end. The slides are then stained with the conventional Pap smear staining reagents. The fixing and staining techniques used in preparing the cells for examination are conventional and can be found in most laboratory handbooks describing methods for carrying out the Pap test. Typical texts include "Diagnostic Cytology And Its Histopathologic Basis", Leopold G. Koss, Second Ed., 1968. Since the polycarbonate film is transparent, it has the advantage of being able to be viewed directly in the microscope without causing any objectionable background. Nevertheless, if desired, the polycarbonate film can be dissolved in a suitable inert solvent which dissolves the polycarbonate film without destroying or injuring the stained cells. A wide variety of such solvents will suggest themselves to those skilled in the art, and the determination of any particular solvent can be readily determined by routine experimentation. It has been found that various halogenated hydrocarbons are particularly effective for dissolving polycarbonate films. Of those halogenated hydrocarbons that can be used, bromoform, chloroform, ethyl dichloride, methylene chloride, and 1,1,2-trichloroethane are especially preferred.
Where it is desired to dissolve the polycarbonate film, in the initial laboratory processing the film is removed from the tampon as described above, and mounted on the mircoscope slide, cell side up, for permeation by the stains. After the staining is complete, the slide is removed from the staining rack and the film is then inverted so that the cell side is down, viz. the cellular material faces the slide. A solvent capable of dissolving the film is then droped onto the film. After the film has dissolved and all of the solvent has evaporated, the slide is then dipped into xylene and a cover slip is placed over the cellular material. The slide is then ready for examination.
As mentioned above, the choice of a suitable solvent used to dissolve the polycarbonate film is not critical, and any solvent can be used that will dissolve the film and at the same time will not have a deleterious effect on the cells to be examined. Suitable solvents can be readily determined by simpile experimentation. For convenience, chloroform is the solvent of choice.
The presence of bacterial and fungal microorganisms can be determined by similar methods. Thus, where a bacterial determination is to be made, there is no need to place the tampon into a fixative. The sample need only be air-dried and sent for cytopathological examination. The dried film is removed from the supporting body as described above and Gram-stained for initial differentiation of microorganisms. The film can also be dissolved as described hereinabove. If the Gram stain reveals the presence of the pathological microorganisms the patient would then be notified with a view initiating appropriate therapy.
The diagnostic tampon of this invention is particularly adapted for mass screening for gonorrhea. As is well-known, the symptoms and signs of acute infection in the adult female are frequently absent, making detection difficult. The presence of N. gonorrhoeae is best determined by preparing the examining growth cultures, in which case it is necessary to keep the cellular specimen moist and relatively warm. This can be accomplished by inserting the tampon into a suitable mailer or container lined with an appropriate growth medium. At the laboratory, the tampon would be discarded, and the mailer containing the growth medium and possible gonorrhea-causing microorganisms would be placed open and flat in a Petri dish containing additional growth medium for continued incubation and subsequent examination.
Appropriate testing procedures for determining the presence of bacterial and fungal microorganisms and the like can be found in "Diagnostic Microbiology", Robert W. Bailey and Elvyn G. Scott, 3rd. ed., 1970.
The exact mechanism by which the polycarbonate film is effective in adsorbing the cellular material is not fully understood. Nevertheless, an understanding of the mechanism is not necessary for the successful practice of the invention. It may very well be that the cellular material adheres to the surface of the film by electrostatic attraction. As mentioned hereinabove, the preferred polycarbonate film is that available under the Trademark "Nucleopore". This particular material has a large number of small-sized pores. While this type of polycarbonate film is preferred, conventional polycarbonate films can be used as well.
With regard to the porous sheet composed of the mixed esters of cellulose, these latter materials cannot be as readily dissolved as can the polycarbonate film for purposes of examination, and the film therefore causes a background when the slide is viewed under the microscope. The background is not, however a particularly objectionable, one, though it is not as good as that provided by a transparent film. The MF-Millipore filters can be easily rendered transparent, however, by applying a few drops of immersion oil having the same index of refraction. Nevertheless, there is no real added difficulty in discerning the fine details of the stained cellular material, and in some cases the porous sheet of the mixed esters of cellulose might be preferred.
As mentined previously, the manner in which the film is attached or secured to the tampon is not of critical importance.
While the above description has been mainly concerned with a tampon adapted for use in the vaginal cavity, it will be apparent that with slight modifications the tampon herein described can be adopted for use in other body cavities, for example, in collecting cellular material from the lower rectum, colon, and buccal cavity, and with modifications of the collection technique, cellular samples from external lesions can be obtained as well.
It will thus be apparent that equivalents or modifications of the herein described tampon may be made without departing from the scope of the invention as set forth in the following claims.
1. Field Of The Invention
The present invention relates to a diagnostic tampon for collecting cellular material, including bacterial, fungal and parasitic elements, from body cavities, in particular the vaginal cavity, wherein the tampon surface is covered with a film of polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose. The tampon of the present invention is particularly adapted for the mass screening and detection of cancer of the pelvic region, in particular the female genital tract. It is of further use in detecting bacterial, fungal or parasitic elements in the female genital tract. The invention also relates to a method for collecting cellular material from the vaginal cavity.
2. Description Of The Prior Art
In recent years the collection of cellular specimens from the human vaginal tract has provided an effective menans for detecting early cancer of the cervix. The cellular material thus obtained is applied, as a cervical vaginal smear, onto a microscope slide and appropriately fixed, stained, and examined. This procedure broadly describes the Papanicolaou Test, popularly known as the Pap Test. The Papanicolaou (cytological) smear is generally obtained by the physician in the office by inserting a speculum into the vagina without lubricant, thereby exposing the cervix. The surface of the external os is then scraped thoroughly and the detritus placed on a glass slide. A second specimen is obtained from the posterior fornix and placed on another glass slide. The two slides are then appropriately treated and sent to the laboratory for cytological study. Unfortunately, for reasons of modesty, many women are reluctant to present themselves periodically for gynecological examination, which usually involves an office visit which, of course, requires further effort by the patient. Many women, particularly those living in remote areas such as rural areas, also find it difficult to present themselves periodically for such examinations. Consequently, there has been a definite need for a simple means for collecting cellular material and the like from the female genital tract, which would be especially suitable for mass screening techniques. It would be desirable to be able to utilize a simple method which could be effectively employed by the patient, preferably at home, without the need for any professional assistance. Towards a means of achieving this aim, there have been proposals to use tampon-like devices adapted for cancer detection. Two of such devices are described in U.S. Pat. No. 2,905,169 and U.S. Pat. No. Re. 24,666.
In one of the prior art techniques, a cotton fiber tampon is covered by a jacket made out of a closely woven sheercloth manufactured from a non-absorbent continuous filament yarn such as nylon. This jacket holds whatever cells are collected from the body cavity on its surface and because the cloth of the jacket is not absorbent the cells are not dehydrated. The collected cells are evenly smeared onto a microscopic slide by rotating the tampon is contact with the slide. The other prior art method involves the use of a tampon manufactured from a nylon or other synthetic sponge, which softens and swells as it adsorbs the bodily secretions.
The prior art devices suffer from various disadvantages, particularly when the collected cells are to be examined a considerable time after they are collected. There is thus a particular need for a device whereby the cellular materials can be collected unassistedly by the patient and thereafter forwarded, either directly or by mail or parcel post, to the examining laboratory or treating physician. Such a procedure is particularly suitable for geographical areas having a shortage of physicians and cytopathological laboratories, and such a device would be extremely suitable for large scale examinations where a considerable number of such specimens could be examined at one time.
The present invention now provides a suitable diagnostic tampon which can be used directly by the patient to collect cellular material from various body cavities, in particular the vaginal cavity. The diagnostic tampon of this invention can be given to the patient directly by the personal physician or mailed to her by a cytopathological laboratory at his request. It is also particularly adapted for dispensation by pharmacies upon a doctor's prescription.
SUMMARY OF THE INVENTION
The present invention provides a diagnostic tampon for obtaining cell specimens, including bacterial and fungal microorganisms and the like, for diagnosis comprising a supporting body which is flexible and stiff enough to be inserted into a body cavity wherein the surface of the supporting body is covered with either a film of polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose.
The present invention also describes a vaginal diagnostic tampon for obtaining cell specimens from the vaginal cavity comprising a cylindrical shaped supporting body having a film of polycarbonate secured to the surface of the supporting body.
It is also an object of this invention to provide a method for collecting cellular material from the vaginal cavity comprising:
a. inserting into the vaginal cavity a tampon where the tampon surface is covered with a film of polycarbonate;
b. withdrawing the tampon;
c. removing the film from the tampon and placing it on a slide;
d. fixing and staining the cellular material on the film; and thereafter
e. examining the stained cellular material.
In the preferred method of collecting and examining the cellular material, after the cellular material on the film is fixed and stained, the film is dissolved with an inert solvent, thereby leaving only the cellular material on the slide.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of the herein described tampon, the surface of which is substantially completely covered with polycarbonate film.
FIG. 2 is a perspective view of a modified form of the tampon on FIG. 1 showing only a portion of the tampon covered by the film.
DETAILED DESCRIPTION OF THE INVENTION
The tampon of this invention, as shown in the accompanying figures, is of a conventional type exemplified by the catamenial devices that are widely used. Referring to the figures, there is shown in FIG. 1 a tampon 10 which comprises a supporting body 13 similar in size and shape to the type generally used for catamenial tampons. This body is of a size and of a material sufficiently flexible and stiff enough to be inserted into a body cavity. For use in the vaginal cavity, the tamon is preferably about 21/4 inches long with a circumference of about 2 inches. The supporting body can be prepared from various materials, such as cotton, cellulose, nylon and the like.
Covering the supporting body 13 is a polycarbonate film or a porous sheet composed of pure, biologically inert mixed esters of cellulose 12. There is also attached at the end of the supporting body a removal string 11. Both the string and the film can be attached to the supporting body by conventional fastenings, such as stitching and the like.
FIG. 2 is a modified form of the preferred tampon shown in FIG. 1, having only part of the supporting body 13 covered by the film. FIG. 2 thus shows a tampon 14 comprising a supporting body 13 partially covered by a polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose 16. Attached to the end of supporting body 13 is a removal string 11. While the film is shown in the figures as having a smooth surface, the diagnostic tampon can also be manufactured so that the outer film covering has a corrugated surface, thereby presenting a larger film surface area to the body cavity.
Although either a polycarbonate or a porous sheet composed of pure, biologically inert mixed esters of cellulose can be used on the surface of the tampon, the polycarbonate film is especially preferred. As is well known, the polycarbonate used to prepare such films are the conventional, thermoplastic, linear polyesters of carbonic acid derived from the polymeric condensation of bisphenols with one or more phosgenes, such as phosgene or its derivatives. A particularly preferred polycarbonate film is that commercially available under the Trademark "Nucleopore", a membrane filter available from the Nucleopore Corporation, Pleasanton, California 94566. This particular plycarbonate film contains a large number of straight-through pores, and it is understood that this film is prepared by treating conventional polycarbonate films according to the method disclosed in U.S. Pat. No. 3,303,085. The commercially available material is available in pore sizes of 20A to 8 microns and can contain 4×10 5 pores/cm 2 of film. A pore size of 5. 0-8. 0μ (microns) is especially preferred. Nevertheless, other polycarbonate films can be used as well, even the conventional polycarbonate films that lack such pores. While the thickness of the film is not critical, a thickness of 8-13 microns is preferred, with a film thickness of 10mμ. being especially preferred.
Another preferred tampon covering is a porous sheet composed of pure, biologically inert mixed esters of cellulose. Typical mixed esters include cellulose acetate propionate and cellulose acetate butyrate. Other mixed cellulose esters can be prepared containing other combinations of lower alkanoate groups, especially low alkanoate groups containing less than 5 carbon atoms. Alternatively, the porous sheet of mixed esters of cellulose can be derived from the mixture of the pure, simple cellulose lower alkanoate esters, such as mixtures of cellulose acetate, cellulose propionate, cellulose butyrate and the like. Cellulose nitrate can also be added to such mixtures. U.S. Pat. No. 2,926,104 discloses a convenient method of preparing microporous cellulose ester films.
An especially preferred series of membranes derived from the mixed esters of cellulose are the commercially available MF-Millipore filters available from the Millipore Corporation, Bedford, Massachusetts 01730. These filters come in about 12 distinct sizes containing pores ranging from 8 microns to 25 millimicrons and are microporous screens containing millions of pores/cm 2 of surface area.
The tampon of the invention can be inserted into the desired body cavity by means of typical tampon applicators, such as for example those disclosed in U.S. Pat. No. 1,926,900 and U.S. Pat. No. 3,101,713.
The diagnostic tampon of this invention can be used to collect exfoliated cells originating in the epithelial, mesothelial and endothelial tissue and also foreign elements such as bacterial or fungal microorganisms and the like. Accordingly, as used herein the expression "cellular material" should be understood to include all of such elements.
It will therefore be seen that the tampon of this invention is particularly adapted for a wide variety of diagnostic purposes. First and foremost it is especially suitable for use in obtaining a cervical vaginal smear for diagnosis in the Pap test. In addition, it can be used to collect pathological bacteria such as Neisseria gonorrhoeae, the causative organism of gonorrhea, as well as pathogenic fungal parasites, such as Candida albicans, the causative agent of Moniliasis, which can be particularly troublesome in the vaginal tract. Other bacterial infections that can be diagnosed include Trichomonas vaginalis and Hemophilus vaginalis, as well as various gonococsal, spirochetal, staphylococcal and streptococcal infections.
For vaginal use in the Pap Test, the tampon is inserted into the vagina to the point of contact with the cervix. For the Pap test, the diagnostic tampon shown in FIG. 1 is preferred since the end of the tampon is covered with the film thereby facilitating collection of cells from the external cervical os. The tampon is left in place several minutes while the patient is in an erect or semi-erect position. The tampon is then withdrawn, utilizing the attached removal string and immediately thereafter placed in a fixative. There are numerous satisfactory fixatives for use in the Pap smear which are well-known to those skilled in the art. Where it is intended that the tampon is to be sent elsewhere for examination, the tampon is inserted into an appropriate mailer which releases the fixative upon enclosing. The patient's identification and history generally accompany the specimen to the laboratory.
At the laboratory, the polycarbonate film covering the tampon is removed and divided into two portions, each of which is placed on a glass slide. The film can easily be removed from the supporting body of the tampon by placing the tampon in an upright position, such as on a spindle, and then with a surgical scapel bisecting the film lengthwise, i.e. vertically, and then cutting the bottom of the film, which remains attached to the supporting body, thereby providing two film sections having rounded edges at one end. The slides are then stained with the conventional Pap smear staining reagents. The fixing and staining techniques used in preparing the cells for examination are conventional and can be found in most laboratory handbooks describing methods for carrying out the Pap test. Typical texts include "Diagnostic Cytology And Its Histopathologic Basis", Leopold G. Koss, Second Ed., 1968. Since the polycarbonate film is transparent, it has the advantage of being able to be viewed directly in the microscope without causing any objectionable background. Nevertheless, if desired, the polycarbonate film can be dissolved in a suitable inert solvent which dissolves the polycarbonate film without destroying or injuring the stained cells. A wide variety of such solvents will suggest themselves to those skilled in the art, and the determination of any particular solvent can be readily determined by routine experimentation. It has been found that various halogenated hydrocarbons are particularly effective for dissolving polycarbonate films. Of those halogenated hydrocarbons that can be used, bromoform, chloroform, ethyl dichloride, methylene chloride, and 1,1,2-trichloroethane are especially preferred.
Where it is desired to dissolve the polycarbonate film, in the initial laboratory processing the film is removed from the tampon as described above, and mounted on the mircoscope slide, cell side up, for permeation by the stains. After the staining is complete, the slide is removed from the staining rack and the film is then inverted so that the cell side is down, viz. the cellular material faces the slide. A solvent capable of dissolving the film is then droped onto the film. After the film has dissolved and all of the solvent has evaporated, the slide is then dipped into xylene and a cover slip is placed over the cellular material. The slide is then ready for examination.
As mentioned above, the choice of a suitable solvent used to dissolve the polycarbonate film is not critical, and any solvent can be used that will dissolve the film and at the same time will not have a deleterious effect on the cells to be examined. Suitable solvents can be readily determined by simpile experimentation. For convenience, chloroform is the solvent of choice.
The presence of bacterial and fungal microorganisms can be determined by similar methods. Thus, where a bacterial determination is to be made, there is no need to place the tampon into a fixative. The sample need only be air-dried and sent for cytopathological examination. The dried film is removed from the supporting body as described above and Gram-stained for initial differentiation of microorganisms. The film can also be dissolved as described hereinabove. If the Gram stain reveals the presence of the pathological microorganisms the patient would then be notified with a view initiating appropriate therapy.
The diagnostic tampon of this invention is particularly adapted for mass screening for gonorrhea. As is well-known, the symptoms and signs of acute infection in the adult female are frequently absent, making detection difficult. The presence of N. gonorrhoeae is best determined by preparing the examining growth cultures, in which case it is necessary to keep the cellular specimen moist and relatively warm. This can be accomplished by inserting the tampon into a suitable mailer or container lined with an appropriate growth medium. At the laboratory, the tampon would be discarded, and the mailer containing the growth medium and possible gonorrhea-causing microorganisms would be placed open and flat in a Petri dish containing additional growth medium for continued incubation and subsequent examination.
Appropriate testing procedures for determining the presence of bacterial and fungal microorganisms and the like can be found in "Diagnostic Microbiology", Robert W. Bailey and Elvyn G. Scott, 3rd. ed., 1970.
The exact mechanism by which the polycarbonate film is effective in adsorbing the cellular material is not fully understood. Nevertheless, an understanding of the mechanism is not necessary for the successful practice of the invention. It may very well be that the cellular material adheres to the surface of the film by electrostatic attraction. As mentioned hereinabove, the preferred polycarbonate film is that available under the Trademark "Nucleopore". This particular material has a large number of small-sized pores. While this type of polycarbonate film is preferred, conventional polycarbonate films can be used as well.
With regard to the porous sheet composed of the mixed esters of cellulose, these latter materials cannot be as readily dissolved as can the polycarbonate film for purposes of examination, and the film therefore causes a background when the slide is viewed under the microscope. The background is not, however a particularly objectionable, one, though it is not as good as that provided by a transparent film. The MF-Millipore filters can be easily rendered transparent, however, by applying a few drops of immersion oil having the same index of refraction. Nevertheless, there is no real added difficulty in discerning the fine details of the stained cellular material, and in some cases the porous sheet of the mixed esters of cellulose might be preferred.
As mentined previously, the manner in which the film is attached or secured to the tampon is not of critical importance.
While the above description has been mainly concerned with a tampon adapted for use in the vaginal cavity, it will be apparent that with slight modifications the tampon herein described can be adopted for use in other body cavities, for example, in collecting cellular material from the lower rectum, colon, and buccal cavity, and with modifications of the collection technique, cellular samples from external lesions can be obtained as well.
It will thus be apparent that equivalents or modifications of the herein described tampon may be made without departing from the scope of the invention as set forth in the following claims.