824
December 1977
TECHNICAL NOTES
An Improved Cervical Radium Applicator 1 G. Ray Ridings, M.D. Design improvements have retained the advantages of a previously described after loading radium system , while facilitating insertion by minimizing the space required for passing the apparatus through the introitus. The mechanical integration of the parts of the apparatus results in smoother insertion, reliability of positioning, and less patient discomfort. IND EX TERMS : Radium· Therapeutic radiology , interstitial and intracavitary • Uterine neoplasms, therapeutic radiology
Radiology 125:824-825, December 1977
A treatment method has been previously described in which fractionation of radium irradiation was achieved in the treatment of carcinoma of the cervix uteri (1,2); it was accomplished by the use of a small-diameter (4 mm) afterloading tandem. There are so many applicators now in use that any new one can hardly avoid having features similar to those of earlier devices; credit must be given to the originators of these . Our report concerns
a further development in the afterloading system. The current apparatus allows for all of the previously described advantages (no anesthesia, knee-chest insertion; afterloading), and it also facilitates the insertion by a mechanical integration of the tandem and ovoids.
PROCEDURE With the patient in the knee-chest position and the retractors in place, the weight of the bowel distends the vagina, and visualization of the vagina and cervix is almost invariably good. After sounding the cervical canal depth, the tandem depth gauge is adjusted and the tandem inserted into the uterine canal. The flattened medial aspect of each ovoid allows it to be slid along the tandem with a minimal need for space (Fig. 2). This is often especially important at the introitus. The left ovoid (the one with the protruding locking arc) is inserted first. Then the tandem retaining post is adjusted and locked. resting on the anterior aspect of the ovoid locking arc; the ovoid (locking arc) thus retains the tandem in place. The second ovoid is then inserted, and the assembly locked together (Fig. 1, g) .
Fig. 1. The applicator: Plastic tubing, containing radium tubes and stylene, fits into the metal tandem (8); radium tubes and stylette (b); metal tandem with cap off; 4-mm outside diameter (TOO = Tandem Depth Gauge; TRP = Tandem Retaining Post) (c); ovoid radium tube inserter, spring-clip type (d); ovids, disassembled. with plastic caps optionally used (OlA = Ovoid locking Arc; PC = Plastic Caps) (e); ovoid radium tube inserter, wire-and-pusher-rod type (GT = Guide Tube, through which passes the size 0 braided surgical steel suture wire; OSP = Ovoid Source Pusher) (f); and assembled unit (g).
825
TECHNICAL NOTES
Vol. 125
Technical Notes
Fig. 2. Inserting second ovoid through introitus: the tandem is retained in place by the locked Tandem Retaining Post(TRP) resting against the Ovoidlocking Arc (OlA) . Utilizing the groove in the medialaspect of the ovoid (betweenthe two leadtabs), almost any introitus space easily accommodates this insertion.
After packing is completed, the ovoid sources are inserted into the ovoids through the hollow handles. This can be done in several ways; three types of inserters are shown in Figure 1. The ovoid handle caps, screwed snugly into place, assure seating of the sources. The radium-loaded plastic sleeve is inserted into the tandem and the cap screwed into place . DISCUSSION
The narrow tandem (4 mm) allows insertion to be accomplished without dilation of the cervical canal ; it is performed as easily as passing a uterine sound. a common office procedure. With this apparatus, tandem and ovoids fit together as a flexible unit. Both are used in each insertion; all radium-irradiated tissues thus receive the full biological advantages of fractionation of the multiple insertions. All the potential for careful packing and reliable dosimetry are retained. Practical advantages include: (a) retention of: capability for good control of positioning of applicators; dose distribution control; protection to rectum and bladder; afterloading; and (b) practical, economical fractionation
of intracavitary irradiation: (1) avoidance of general anesthesia, its morbidity and its expense ; (2) avoidance of operating room expense; (3) each hospital admission requires only an overnight stay, greatly reducing hospital costs. Morbidity is also reduced. ACKNOWLEDGMENT: St. Paul Hospital, Dallas, Texas, supportedthe construction of the original model of the ovoid, thus making possible a full utilization of the potential of the system. REFERENCES
1. Ridings GR: Radiation therapy for carcinoma of the cervix uteri. J Okla St Med Assoc 57:347-353, Jul 1964 2. Ridings GR: Fractionated intrauterine radium applications: use of a small-diameter afterloading intrauterine applicator . Am J Roentgenol 89:500-501, Mar 1963
1 From 937 Broadway, Cape Girardeau, Missouri, 63701 . Accepted ss for publication in February, 1977.
December 1977
TECHNICAL NOTES
An Improved Cervical Radium Applicator 1 G. Ray Ridings, M.D. Design improvements have retained the advantages of a previously described after loading radium system , while facilitating insertion by minimizing the space required for passing the apparatus through the introitus. The mechanical integration of the parts of the apparatus results in smoother insertion, reliability of positioning, and less patient discomfort. IND EX TERMS : Radium· Therapeutic radiology , interstitial and intracavitary • Uterine neoplasms, therapeutic radiology
Radiology 125:824-825, December 1977
A treatment method has been previously described in which fractionation of radium irradiation was achieved in the treatment of carcinoma of the cervix uteri (1,2); it was accomplished by the use of a small-diameter (4 mm) afterloading tandem. There are so many applicators now in use that any new one can hardly avoid having features similar to those of earlier devices; credit must be given to the originators of these . Our report concerns
a further development in the afterloading system. The current apparatus allows for all of the previously described advantages (no anesthesia, knee-chest insertion; afterloading), and it also facilitates the insertion by a mechanical integration of the tandem and ovoids.
PROCEDURE With the patient in the knee-chest position and the retractors in place, the weight of the bowel distends the vagina, and visualization of the vagina and cervix is almost invariably good. After sounding the cervical canal depth, the tandem depth gauge is adjusted and the tandem inserted into the uterine canal. The flattened medial aspect of each ovoid allows it to be slid along the tandem with a minimal need for space (Fig. 2). This is often especially important at the introitus. The left ovoid (the one with the protruding locking arc) is inserted first. Then the tandem retaining post is adjusted and locked. resting on the anterior aspect of the ovoid locking arc; the ovoid (locking arc) thus retains the tandem in place. The second ovoid is then inserted, and the assembly locked together (Fig. 1, g) .
Fig. 1. The applicator: Plastic tubing, containing radium tubes and stylene, fits into the metal tandem (8); radium tubes and stylette (b); metal tandem with cap off; 4-mm outside diameter (TOO = Tandem Depth Gauge; TRP = Tandem Retaining Post) (c); ovoid radium tube inserter, spring-clip type (d); ovids, disassembled. with plastic caps optionally used (OlA = Ovoid locking Arc; PC = Plastic Caps) (e); ovoid radium tube inserter, wire-and-pusher-rod type (GT = Guide Tube, through which passes the size 0 braided surgical steel suture wire; OSP = Ovoid Source Pusher) (f); and assembled unit (g).
825
TECHNICAL NOTES
Vol. 125
Technical Notes
Fig. 2. Inserting second ovoid through introitus: the tandem is retained in place by the locked Tandem Retaining Post(TRP) resting against the Ovoidlocking Arc (OlA) . Utilizing the groove in the medialaspect of the ovoid (betweenthe two leadtabs), almost any introitus space easily accommodates this insertion.
After packing is completed, the ovoid sources are inserted into the ovoids through the hollow handles. This can be done in several ways; three types of inserters are shown in Figure 1. The ovoid handle caps, screwed snugly into place, assure seating of the sources. The radium-loaded plastic sleeve is inserted into the tandem and the cap screwed into place . DISCUSSION
The narrow tandem (4 mm) allows insertion to be accomplished without dilation of the cervical canal ; it is performed as easily as passing a uterine sound. a common office procedure. With this apparatus, tandem and ovoids fit together as a flexible unit. Both are used in each insertion; all radium-irradiated tissues thus receive the full biological advantages of fractionation of the multiple insertions. All the potential for careful packing and reliable dosimetry are retained. Practical advantages include: (a) retention of: capability for good control of positioning of applicators; dose distribution control; protection to rectum and bladder; afterloading; and (b) practical, economical fractionation
of intracavitary irradiation: (1) avoidance of general anesthesia, its morbidity and its expense ; (2) avoidance of operating room expense; (3) each hospital admission requires only an overnight stay, greatly reducing hospital costs. Morbidity is also reduced. ACKNOWLEDGMENT: St. Paul Hospital, Dallas, Texas, supportedthe construction of the original model of the ovoid, thus making possible a full utilization of the potential of the system. REFERENCES
1. Ridings GR: Radiation therapy for carcinoma of the cervix uteri. J Okla St Med Assoc 57:347-353, Jul 1964 2. Ridings GR: Fractionated intrauterine radium applications: use of a small-diameter afterloading intrauterine applicator . Am J Roentgenol 89:500-501, Mar 1963
1 From 937 Broadway, Cape Girardeau, Missouri, 63701 . Accepted ss for publication in February, 1977.
