1. Field of the Invention
The present invention relates to a vaginal speculum of the type comprising a pair of elongated vagina engaging members movable apart relative to each other and adapted to extend into the vagina.
2. Description of the Prior Art
Such vaginal specula are well known. In general, they are referred to as the self retaining type, in other words, they can be inserted into the vagina, and when the vagina engaging members are moved apart to dilate the vagina to the desired amount, the vagina engaging members may be locked in position. In general, these specula are used on conscious subjects. However, they may also, if desired, be used on unconscious subjects.
A particular type of vagina speculum in common general use comprises a pair of vagina engaging members pivoted together at one end. Cranked handles extend sidewardly from the vagina engaging members beyond the pivot point to substantially overlap each other. In general a screw member extends from one handle to slidably engage a hole in the other handle. Rotation of a nut on the screw member moves the handles towards and away from each other to operate the vagina engaging members. When the vagina engaging members have been adjusted to achieve the desired dilation of the vagina, the nut is then locked on the screw member.
There are a number of problems associated with these known vaginal specula. Firstly, because of the construction of the speculum, it is impossible to insert the vagina engaging members into the vagina so that the pivot point is adjacent the introitus of the vagina. The pivot point must always be outside the vagina and is usually about 2 cm from the introitus. Thus, as the members are moved apart to dilate the interior of the vagina, the introitus is dilated a proportional amount. In other words, the amount to which the introitus is dilated is a function of the distance the vagina engaging members are moved apart. It will be appreciated that this causes considerable problems in the operation of the speculum. The introitus is a particularly sensitive part of the vagina, and while it is distensible, excessive dilation of the introitus causes considerable discomfort and pain to the subject.
Secondly, since in these known vaginal specula, it is necessary to pivot the vagina engaging members together while still in position in the vagina in order to extract the speculum, in many cases, the tips of the two members nip the cervix. Additionally, because the fornix of the vagina tends to be in folds when not dilated, as the vagina engaging members are moved together, the fornix may also be nipped by the members. Needless to say, this is undesirable and particularly dangerous in pregnant subjects.
Thirdly, because the handles of these devices are operated by rotating the nut along the screw member, this operation tends to be noisy, and in many cases tends to distress the subject.
Fourthly, while these known specula can be auto-claved, because of the construction of the devices, particularly around the pivot mechanism, it is impossible to remove the stains in secluded areas around the pivot connection. This, needless to say, is objectionable.