Clinical estimation of bladder and rectal doses from high dose rate intracavitary irradiation in carcinoma of the cervix uteri has been initiated on a routine basis in an effort to obtain the optimum radiotherapeutic dose. Simulation films with contrast media are used to image the bladder and rectum, and dose rates are estimated at various interesting points with the aid of treatment planning computer, NEC Therac-2300. Fifty-three patients have been reviewed in order to ascertain the correlation between radiation dose at interesting points in the bladder and rectum and the dose at Point A and B. The dose ratio between doses at Point A and interesting points in an important clinical factor in evaluating the treatment planning. This also serves as documentation of the dose to normal structures within the treatment volume. Authors conclude that obtained data are within acceptable ranges and routine simulation films of the bladder and rectum after administration of contrast media with dose calculations at interesting points provide important information for optimizing radiotherapy planning in the treatment of cervical carcinoma without increased time and effort or patient's discomfort.
Cervix Uteri ; Contrast Media ; Female ; Humans ; Radiotherapy ; Rectum ; Urinary Bladder ; Uterine Cervical Neoplasms*

The object of this study was to determine the difference of radiation effect in different fractional does and to establish optimal fractionation schedule on the whole-abdominal X-ray irradiation. Total 160 mice were irradiated with 150 KVP, 15 mA orthovoltage x-ray machine and two different fractionation (100 cGy/Fr. and 200 cGy/Fr.) were used. Body weight, hemoglobin and WBC count with differential count were analyzed according to the same amount of total dose, same field size and two different fractionation schedules. The results of this study were summarized s follows: There was no significant difference in body weight and hemoglobin concentration by sex or fractional dose. Leukopenic change was prominent in the 3,000 cGy irradiation group and the proportion of decrease was remarkable in the 200 cGy/Fr. Group than 100 cGy/Fr. Group. Progressive decrease of lymphocyte count and reciprocal increase of neutrophil count were noted as dose increment. The effect of the fractional does on WBC count and proportion of lymphocyte were significant. This suggests that judicious selection of fractional dose may be important in clinical radiotherapeutic practice.
Animals ; Appointments and Schedules ; Body Weight* ; Lymphocyte Count ; Lymphocytes ; Mice* ; Neutrophils ; Radiation Effects*

No abstract available.
Rectal Neoplasms*

Since discovery of X-rays, radiotherapy has evolved into one of the most scientific branches of medicine and has established its role as the primary line or the secondary line of attack, after surgery,. in the treatment of malignant cancers. Nowadays its importance is illustrated by the fact that as many as 70 per cent of all pastients with cancer will receive radiation therapy at sometime during their disease process. Biologic effects-of X-rays began to be apparant soon after the discovery by Roentgen in 1895. In clinical radiotherapy, the biologic endpoint of most importance is loss of cellular reproductive ability or clonogenicity. One of the commonest ;nays to assess cell survival is to use an in vitro plating assay. We analyzed radiation effect on colony formation of HaLa. S3(SC) cell line and obtained results are as follows The plating efficiency is 0.464. The shape of cell survival curve is similar to multi-target plus single hit component model. Estimated values of Do, Dq, and extrapolation number are 150 cGy, 80 cGy and 1.7 respectively. We reported these experimental data with review of literature.
Cell Line* ; Cell Survival ; Radiation Effects ; Radiotherapy

PURPOSE: To evaluate the role of MRI in the management of cervical cancer treated by conventional four-field whole pelvic irradiation. METHOD AND MATERIAL: Between 1993-march and 1994-february, 20 patients(4 Stage I B, 3 Stage U A, 13 Stage U B) with invasive cervical cancer were eligible for evaluation of accuracy of conventionally designed lateral treatment field without MRI determination. RESULTS: 5 out of 20 Patients had inadequate margin without MRI. The position of uterine fundus was more important than cervix in correction of field size and the center of treatment field. CONCLUSION: This Preliminary date show MRI determination of uterine position prior to radiotherapy planning is essential in the case of four-field whole pelvic irradiation technique.
Cervix Uteri ; Female ; Humans ; Magnetic Resonance Imaging* ; Radiotherapy* ; Uterine Cervical Neoplasms*

In electron therapy, low melting point alloy is used for shaping of the field. Electron field shaping material affect the output factor as well as the collimator system. The output factors of electron beams for shaped fields from NELAC-1018 were measured using ionization chamber of Farmer type in water phantom. The output factors of electron beams depend on the incident energy, inherent collimator system and the size of shaped field. Obtained results were followings. 1. In the smaller applicator, output varied extremely according to extent of collimator opening. 2. The higher energy, the output is less varied according to treatment field at small field.
Alloys ; Farmers ; Freezing ; Water

The stereotactic radiosurgery using ionizing radiation of high energy is a technique for exadicating intracranial small tumors, which are inaccessible or unsuitable for open surgical technique. For such a small field radiosurgery, TLD or film dosimetry is essential. The three dimensional dose planning of radiosurgery was performed with dose planning computer system (Therac 2300). The target dose distribution and its error according to patient position were discussed. And were measured of circular cone which specially designed in our Hospital. The position error of Rando Phantom compared with CT were 0.4 mm in the AP-LAT section and in the AP-VERT section, 1.0 mm in the AP-VERT 45°section. The ratio of accuracy of the gantry and couch rotation were 1.5 mm diameter for central axis of 18MeV linear accelerator. Our study suggested that radiosurgery of small field in out department will be appropriate for clinical application.
Computer Systems ; Film Dosimetry ; Humans ; Particle Accelerators ; Radiation, Ionizing ; Radiosurgery*

Uterine cervical cancer is the most common malignancy in Korean women. In spite of recent development of early diagnostic and therapeutic modalities, about 40% of treated patient will develop relapse. So more aggressive local treatment such as more extensive surgery and higher radiation dose and administration of systemic chemotherapy will promote the curability but treatment related complications cannot be avoidable. We used 22 cases of early cervical cancer, treated with surgery and post-operative radiotherapy, clinical data of these patients were analyzed to determine relationship between clinical parameters and final outcome. Three out of 22 cases revealed relapse and one patient showed rectovaginal fistula and another patient showed small bowel obstruction and the other patient showed rectal obstruction. Two out of three recurrence were stage IIa and the other one case was stage Ib adenocarcinoma with lymphovascular involvement. Nineteen out of 22 cases were followed without remarkable side effect or treatment related complication or sequelae. We concluded that out treatment policy was safe and effective to eradicate high risk postoperative cervical cancer with acceptable side effects or complication.
Adenocarcinoma ; Drug Therapy ; Female ; Humans ; Radiotherapy* ; Rectovaginal Fistula ; Recurrence ; Uterine Cervical Neoplasms*

In recent years there has been a growing interest in all forms of rotational therapy, and many different types of therapy machines designed for this kind of treatment have become available. To the medical radiation physicist, the dosimetry of rotation therapy has presented a number of interesting problems, and much useful work has been published on the basic date of dose distribution and dosage calculation. The setting dose for ARC therapy were obtained by computer calculation and measurement with cylindrical phantom. Authors compared computer calculation with measured value. And in ARC therapy, the region of maximum dose in shifted from the tumor center. The extent of shift was analyzed by isodose distribution for ARC therapy techniques.
Particle Accelerators*

The first successful bone transplantation carried out in 1688 by Van Meek'ren, a Dutch surgeon. The ideal bone substitute should be biocompatible, osteoinductive or at least osteoconductive, available in unlimited quantity, low cost and have satisfactory mechanical properties. To accomplish these goals, autografts are still preferred material. However, bone harvesting procedures have been focused to solve the following problems; necessity of a second surgical site, morbidity and potential deformity of the donor site, an increased operative time, donor availability limitations, and resorption of autogenic bone grafts.Ten adult white New Zealand rabbits, three, 10 mm in diameter, full layer skull defects were made in the frontoparietal bone. Two bone defects were filled with hydroxyapatite and powdered eggshell, the other defect was not filled(control). All animals were sacrified at 10 weeks, the specimens were examined macroscopically to test for graft mobility. The graft with surrounding bone was then harvested and studied by histology. The results were as follows: 1. Control: Bone regeneration occurred nearly complete. 2. Hydroxyapatite: Macroscopically - No encapsulation. Despite a gross delineation between implant and bone, imlant was firmly united to bone. Histology - Bony trabeculae surrounded by proliferated connective tissue are observed in the defect site and implant. Osteoblastic rimming is noted along the bone fragments 3. Powdered eggshell:Macroscopically - Grafted site was encapsulated by proliferated connective tissue and palpable softer than the surrounding bone. Histology - The presence of eggshell particles encapsulated by fibrous connective tissue. Partial bone regeneration from the defect margin was noticed, but the bone healing was never complete. In conclusion, the use of safe and inexpensive material is recommended for filling limited bone defects in non-weight bearing areas. The use of powdered eggshell for bone substitute may also be considered, after further studies, to access its long term stability, porosity and biocompatibility.
Adult ; Animals ; Autografts ; Bone Regeneration ; Bone Substitutes* ; Bone Transplantation ; Congenital Abnormalities ; Connective Tissue ; Durapatite ; Humans ; Operative Time ; Osteoblasts ; Porosity ; Rabbits ; Skull ; Tissue Donors ; Transplants