1 2
neous and objective indication of the presence or ab
PHYSIOLOGICAL PROBE sence of neoplastic activity to be provided.
The essential advance inherent in the present inven
The present invention relates to a physiological probe tion is the measurement of the magnitude of electro
for identifying tissue which is suspected of being physi- 5 magnetic radiation in the near light region mentioned
ologically changed as a result of commencement of above reflected from the tissue at two different wave
neoplastic activity or pre-activity. lengths. The ratio of the reflected magnitudes appear to
Although the preferred embodiment of the present provide a reliable indication of the presence or absence
invention to be described hereafter has particular appli- 0f neoplastic activity.
cation to cervical lesions, the present invention is also 10 According to the present invention there is disclosed applicable to lesions of various tissues which can be a physiological probe for identifying cervical tissue inspected by means of an endoscope, for example, which is suspected of being physiologically changed as which can be inserted into the lungs, into the abdominal a result of commencement of neoplastic activity or canal, or into the rectum. Thus the present invention is pre-activity of a cervical lesion, not generally applicable to tissues of interior organs 15 said probe having one end shaped to face said cervisuch as the liver or kidneys. ca| tissue and comprising at least two paths for electroIt is believed that by doing a spectral analysis of the magnetic radiation in the range of from 200 nm to tissue an indicator of cancerous or precancerous activ- 12)000 nm, at least one of said paths leading to said one ity can be found. end and arranged to convey said electromagnetic radiaWhen viewed under white light, this cancerous or tion in a first direction towards said one end, and at least precancerous activity makes itself apparent by in- one 0f said paths leading from said one end and arcreased redness of the tissue. However, because there is ranged to convey said electromagnetic radiation in a a wide variety of perceived color, bought about by the second direction away from said one end; reflection, or non-absorption, of light by tissue, it is not 2J a first electromagnetic generator means connected to possible to accurately predict the presence or absence of said at least one flrst direction path to transmit said neoplastic activity simply based on the color of the electromagnetic radiation at a first wavelength within tissue alone. said range along one of said first direction paths and a Although white light is convenient to use, white light second electromagnetic generator means connected to represents only a very small band of wavelengths of 3Q said at leagt. one flrst direction path to transmit said electromagnetic radiation in the range of say, from 200 electromagnetic radiation at a second wavelength nm to 12,000 nm which may be loosely classed as hav- wkhin said al one of said first direction thS( ing properties similar to that of light. This band of said second wavelength being different from said flrst wavelengths includes ultraviolet light, visible light and waveleneth
infra red radiation. It is generaUy desirable to work with 35 recdver means connected to ^ at least one second
a wavelength close to visible light since the further one ... tQ receivg said ... at said first and sec.
moves away from this band of wavelengths, the more ond wavelengths reflected by said tissue, and compara
difficult and complicated the apparatus generally be- tQr means tQ ate (he fatio of {he mtudes of said
comes. A major advantage of electromagnetic rad.ation and ^ same ^ * ... ...
,n this region is that it is not effected by, for example, 40 tQ therefe w ^ ^ c£ndition.
mucus present on the cervix. . ' , ., , . ,
T, r ., r ■ 1 L In one form two paths only are provided. A single
For many years the presence of cervical cancer has ,, r -j • i_
r , ^ n a receiver and two generators are provided with the genbeen detected using a process known as the Pap Smear. , „ . .* . / „ „ , e This is a chemical lest which relies upon the collection erators transmitting alternatively. If preferred two re
of a sample of material immediately adjacent the open- 45 cfvers ?an be Prov,ded and swltched t0 °Perate from
ing of the cervix. This test is not as reliable as it might tn? sln8le return path.
be because of variations introduced by the ability of the In. another form t^ee paths are provided. A single
operator to accurately take a sample, the need for the recelver 18 connected to the return path and each gener
sample to be sent away to a laboratory for analysis ator ,s connected to a corresponding sending path. In a
where the sample is viewed under magnification by an 50 further form four Paths are Provlded WIth tw0 receivers
operator who makes a subjective assessment of the tis- each connected 10 a corresponding return path.
sue Embodiments of the present invention will now be
If a positive result is produced, the patient is then described with reference to the drawings in which:
examined by means of a colposcope which enables a FIG- 1 is a schematic representation of the probe of
magnified view of the cervix to be examined by a skilled 55 the preferred embodiment approaching contact with
practitioner who makes a subjective judgement of the trie tissue of a cervix,
tissue observed. Any suspect regions of the cervix can FIGS. 2(a-J) is a graph of the timing relationships of
then be burnt away using a laser, for example, and the the apparatus of FIG. 1,
cervical tissue then re-grows. Such easy preventative FIG. 3 illustrates in schematic form the circuit ar
treatment is only possible if the lesion is detected at an 60 rangement required to realize the apparatus of FIG. 1,
early stage. Since Pap Smears are normally conducted FIG. 4 is a view similar to FIG. 1 but illustrating an
on an annual basis, a faulty test during one year can alternative arrangement of paths,
mean that a lesion is not detected until the following FIG. 5 is a view of a probe of a further embodiment
year, at the earliest. illustrating a still further arrangement of optical paths,
It is the object of the present invention to substan- 65 and
tially overcome, or ameliorate, the disadvantages inher- FIGS. 6 and 7 are schematic cross-sectional views of
ent in Pap Smear testing by the provision of a physio- a cervix illustrating respectively the correct and Incor
logical probe which enables a substantially instanta- rect probe attitudes.
