Plastic vaginal cylinder; accessory to the expanding cervico-uterine radium applicator.

Abstract

In the management of carcinoma of the cervix, unless the multiple distributions of the radium intensities in the uterine canal and vaginal vault are controlled both mechanically and physically, thereby facilitating accurate duplication of the dose in gamma roentgens (or their equivalent) at two or more fixed distant pelvic points (A/B r coefficient of absorption), the clinical reporting of results and the technical evaluation and comparison of the different technics are of questionable statistical value. In previous studies we presented data relating to the photometric radiation effects upon slow emulsion films of supposedly standard radium technics and observed that there was a greater lack of uniformity and distribution of the pelvic radiation intensities than we had anticipated. This was found to be due in part to faulty positioning of the radium capsules, although at the time of our application we, like other therapists, had egotistically assumed confidence in our ability to pack accurately and fix permanently these loose radium sources in relation to the primary and potential malignant parametrial lesions. Routine radiographic examinations of the pelvis soon revealed that these wandering radium capsules were drifting into dangerous positions, toward the bladder or rectum. In the interest of protection of the normal structures, we removed and re-applied the radium in an attempt to correct these faulty positions, usually without success. Vaginal deformities or uterine displacements, or both, added to the difficulty of these reapplications. Our only alternative, if we hoped to avoid “hot-spots” and the probable development of slow healing ulcers or vaginal fistulas, was to reduce the total radium dose when the radiographic examination indicated that the loose capsules continued to remain in a position dangerous to normal pelvic tissues. In Figure 1 three removable radium tubes are shown, completely filling the uterine canal, with six vertical capsules uniformly distributed throughout the vaginal vault, designed, when fully expanded, to partially surround the lesion at the cervical os as well as to irradiate directly the parametrial fields. The two lateral vaginal capsules are removable. When the plastic cylinder, B, is attached to the protruding handle of the radium applicator it not only protects the outer half of the vaginal mucosa, but also serves as a fulcrum for effective and safer control of the radium sources in the mid-pelvic corridor between the bladder and rectum. In Figure 2, the expanding radium sources are viewed in the opposite lateral position within the pelvis. The respective ends, G, of the vaginal capsules are protected with lead and 2 mm. of brass. The radium needles have an over-all length of 19 mm. and an active radium length of 12 mm.