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At least 73 records · Page 4Linked to original sources
PubMed1975

The Budd-Chiari syndrome: correlation between hepatic scintigraphy and the clinical, radiological, and pathological findings in nineteen cases of hepatic venous outflow obstruction.

From 1965 to 1972, 19 patients with the Budd-Chiari syndrome were investigated. An underlying diagnosis was made in 10 cases, polycythemia rubra vera being the commonest etiology. Percutaneous liver biopsy confirmed the diagnosis in 18 patients, and in 14 the site of hepatic vein obstruction was defined or its presence suggested by hepatic venography. Hepatic scintiscanning showed predominant central localization of radiocolloid in 7 patients. In another 8 patients this appearance was present in association with other less specific features. These findings were correlated with inferior vena cavography in 13 patients in whom a characteristic narrowing and distortion of the vein throughout its intrahepatic course was noted. In 3 other patients, the vein was found to be occluded. Autopsy evidence in 6 patients suggests that the central concentration of radiocolloid on scintiscanning and the narrowing and distortion of the inferior vena cava were due to disproportionate enlargement of the caudate lobe. Additional studies indicated that the separate venous drainage of the caudate lobe may be preserved when the main hepatic veins are occluded and that hypertrophy of the caudate lobe occurs because of its relatively more efficient perfusion. Demonstration of the enlarged caudate lobe by scintiscanning and inferior vena cavography provides valuable diagnostic support for the Budd-Chiari syndrome.

Adult↗
PubMed1996

Salvage treatment for inoperable neck nodes in head and neck cancer using combined iridium-192 brachytherapy and surgical reconstruction.

The results of debulking surgery and re-irradiation with radioactive implants (brachytherapy) are reported for 39 patients with inoperable metastatic neck nodes from primary head and neck cancers. For 13 patients conventional salvage by partial debulking surgery and brachytherapy proved effective, with 68 per cent control at 1 year, but six patients suffered severe radiation fibrosis, necrosis and contractures. Some 26 patients were treated by combined tumour debulking, skin resurfacing and brachytherapy implant. Initial tumour control and freedom from serious toxicity was achieved in 24 patients. Local control was achieved in 63 per cent of patients at 1 year, with a serious morbidity rate of 12 per cent.

Adult↗
PubMed1995

Double-film technique for the determination of the homogeneity of line sources.

A new technique is presented for determining the homogeneity of the linear activity. The method uses two x-ray films that are firmly pressed against opposing sides of a needle containing a radioactive line source. The homogeneity of the linear activity of 68 iridium-192 wires has been measured. About 80% of the measured linear activities showed deviations of no more than 5% from the mean; about 20% of the measured linear activities showed deviations of 5%-10% from the mean. Individual wires may contain deviations of 5% or more extended over several centimeters, which causes the dose in the prescription point to deviate 5% from the desired value. Four wires (8%) were rejected for this reason.

Biophysical Phenomena↗
PubMedDate not supplied

[The brachytherapy with low dose-rate iridium for prostate cancer].

PURPOSE: Brachytherapy as an option for the treatment of prostate cancer has been commonly performed in USA. As the permanent seeding of the radioactive materials is strictly restricted by the law in Japan, brachytherapy must be performed by the temporary implant. This treatment has been performed at a few facilities in Japan mostly using high dose-rate iridium. Only our facility has been using low dose-rate iridium (LDR-Ir) for prostate cancer. This study evaluates the clinical results of the treatment. PATIENTS AND METHODS: Since December 1997 to December 1999, 26 patients with histologically diagnosed as prostate cancer (Stage B, 92%; Stage C, 8%) underwent brachytherapy. Twenty-two patients received brachytherapy alone, three were treated with a combination of brachytherapy and external beam radiotherapy (ERT) and one was treated with a combination of brachytherapy and neoadjuvant endocrine therapy. Patients ranged in age from 61 to 84 (median 76) years old. Treatment was initiated with perineal needle placement. From 10 to 14 needles were placed through the holes on the template which was fixed to the stabilizer of the transrectal ultrasound probe. After the needle placement. CT scan was performed to draw distribution curves for the treatment planning. LDR-Ir wires were introduced to the sheath and indwelled during the time calculated from dosimetry. Peripheral dose was 70 Gy for the monotherapy of brachytherapy. For the combination therapy, 40 Gy was given by brachytherapy and 36 Gy with ERT afterwards. LDR-Ir wires were removed after completion of the radiation and patients were followed with serum PSA level and annual biopsy. RESULTS: During 2 to 26 (median 12) months follow-up, 8 out of 9 patients with initial PSA level above 20 ng/ml showed PSA failure. All 13 patients with initial PSA level lower than 20 ng/ml were free from PSA failure. Eight out of 11 patients with Gleason's score 7 or higher showed PSA failure, and all 14 patients (including three patients with combined therapy) with Gleason's score 6 or less were free from PSA failure. Annual biopsy was performed in 8 patients, and 4 patients histologically revealed tumor free and 4 patients (two of them showed PSA failure) were tumor positive. No major complication was observed, however, some minor side-effect as irritability was seen in 65% of the patients. CONCLUSIONS: The results showed that brachytherapy with LDR-Ir was an acceptable treatment as long as the patients were selected strictly with PSA level and Gleason's score. A good candidate for this treatment is the patient whose PSA level is lower than 20 ng/ml and Gleason's score is 6 or less. The treatment is effective and safe, but further observation is necessary to reach the conclusion.

Aged↗
PubMed1979

[Endocurietherapy in cancer of the bladder. A new technique by implant of 192iridium with Cyponil tubes (author's transl)].

The Authors propose a new technique of interstitial implant in cancer of the bladder based on the direct implant of 192 Iridium with Cyponil tubes. The tubes are roughly 2 metres in length with a radioactive wire in one third of the tube length. These wires are kept in a lead container during the complete implantation of the tube. After opening the bladder the uncharged part of the tube is passed through the inner walls by means of surgical needles. The number of the tubes depends on the size of the tumour and they are placed parallel to each other. They are then drawn until the radioactive part covers the tumour site. One end of the Cyponil tube is then pulled through the urethra and stitched to the skin, the other end is drawn through the surgical incision and attached to the abdominal skin. A Folley catheter is put on the bladder is such a way as to keep it blown up. It is then sutured. A radiography is carried out so as to determine the dosage. At the end of the therapy the stitches of the Cyponil tubes are cut and are removed by extraction.

Brachytherapy↗
PubMed1990

Role of brachytherapy in the management of pulmonary and mediastinal malignancies.

Brachytherapy, the permanent or temporary implantation of radioactive sources, has been performed in limited numbers of patients with lung cancer over the last 50 years. Because of renewed interest in this modality, we reviewed our experience with 103 patients treated over a 7-year period. The mean age of this group was 55.5 years (range, 1 to 84 years). Primary lung cancer accounted for 82 patients (79.6%); metastatic lesions to the lung, 13 (12.6%); and mediastinal malignancies, 8 (7.8%). Indications for brachytherapy included mediastinal and chest wall invasion in 42 patients (40.8%), unresectable tumors and mediastinal adenopathy in 30 (29.1%), medical contraindications to extensive pulmonary resection in 20 (19.4%), and irradiation of excised lymph node beds in 11 (10.7%). Seeds labeled with radioactive iodine 125 alone were used in 65 patients (63.1%), afterloading catheters containing iridium 192 sources in 25 (24.3%), and both in 13 (12.6%). There were no operative deaths. With a mean follow-up of 18.6 months, the mean and median survivals for the entire group were 17.3 and 14.0 months, respectively. The 1-year, 2-year, and 3-year survivals for the entire group were 67.9%, 38.7%, and 27.8%, respectively. In summary, brachytherapy offers a useful surgical approach in patients in whom unresectable pulmonary or mediastinal malignancies are found at the time of thoracotomy or in patients previously treated with other modalities for whom limited therapeutic alternatives exist.

Adolescent↗
PubMed1980

Stereotactic treatment of brain lesions. Biopsy, interstitial radiotherapy (iridium-192 and iodine-125) and drainage procedures.

Integrating CT imaging techniques into stereotactic procedures makes it easy to puncture cysts, take biopsies from neoplastic and nonneoplastic lesions, and place radioactive material in tumors at exact and reproducible sites. A stereotactic program of interstitial radiotherapy in deep-seated brain tumors has been applied in 326 cases as of December 31, 1979 (270 cases using iridium-192 and 56 cases using iodine-125). The use of iodine-125 is now favored since it requires less radiation protection due to its soft 28-35 keV radiation; at the same time, however, it possesses a comparable half life of 60 days. In 126 cases, stereotactic biopsy was used exclusively for diagnostic purposes followed by open craniotomy or conventional radiation. Cystic brain tumors (i.e., craniopharyngiomas and cystic low grade gliomas) were permanently drained by insertion of Rickham reservoir catheters in 61 cases. Stereotactic ventriculocisternostomies were carried out in cases of hydrocephalus and drainage of suprasellar arachnoid cysts was performed in 15 cases. A simple method of projecting CT images onto stereotactic X-ray pictures provides an exact mapping of lesions within the actual stereotactic brain space. The results of this series of patients strongly suggest that exploratory craniotomies and free-hand punctures can no longer be advocated. No radiation treatment should be considered without histological confirmation. The more clearly the volume of a tumor can be defined, the more favorable the results of interstitial irradiation in otherwise unresectable tumors.

Biopsy↗
PubMed1977

[Technique for intracavitary radiotherapy using an iridium 192 wire ("umbrella") in the treatment of adenocarcinoma of the body of the uterus (author's transl)].

The description of an intrauterine device for the application of local radiotherapy in non-radioactive preparation. The device consists of polyethylene tubes froming two perpendicular loops joined and fixed and their topmost point by ligature. A traction wire is used to open these loops, therby obtaining a cuboid target-volume from four radioactive lines. Dosimetry for this technique (known as "umbrella") may be obtained using a computerised programme.

Adenocarcinoma↗
PubMed1999

A lost pigtail.

Explore the source record for details and available documents.

Adult↗
PubMed1979

[A projector of iridium 192 wires: motivations and preliminary studies (author's transl)].

Though the majority of procedures involved in curietherapy with Iridium 192 wires cause very few problems concerning radiation protection, this is not true in all cases: in elderly of debilitated patients, young children, or when using special techniques (curietherapy for prostate of bladder cancers for example). In these cases, the need for frequent treatments exposes the therapists to increased doses. The projector of Iridium 192 wires was conceived in order to reduce this irradiation hazard. A simple manipulation places the radioactive wires in a lead container during treatment, and then replaces them in the right position after therapy. This apparatus appears to offer the possibility of: an almost total protection of the therapists, and thus an opportunity for enlarging the indications for curietherapy; an improved quality of treatment to the patient during the application.

Aged↗
PubMed1993

Prostate brachytherapy. An overview.

BACKGROUND: Prostate brachytherapy represents one of the oldest techniques of using radiation therapy to treat prostate cancer. Over the past 10 years, there have been major changes in the types of prostate brachytherapy that can be performed with the introduction of new radioactive isotopes, new afterloading techniques, and an improved understanding of the radiobiology associated with differing dose rates. METHODS: Prostate brachytherapy can be divided into temporary implantation using high activity sources such as iridium-192, or permanent brachytherapy using the interstitial implantation of iodine-125 or palladium-103 sources. There are various techniques that can be used to actually insert the radioactive material into the prostate. This can be done as an open or closed procedure and can be performed via a suprapubic or a perineal retropubic approach. The use of remote afterloading has substantially reduced the radiation protection problems associated with manually loaded radioactive sources. RESULTS: Results using brachytherapeutic isotopes in the treatment of prostate cancer have been variable, but it appears that using the higher dose rate sources and delivering a high relative integral dose to the prostate can result in improved histologic control of prostate cancer. In patients with aggressive prostate cancer, the use of iodine-125 permanent implantation has not been successful. CONCLUSIONS: The role of brachytherapy in the treatment of prostate cancer remains an exciting alternative in the management of prostate cancer. Its role is becoming more defined in the treatment of large, bulky prostatic neoplasms as a way of improving the dose distribution achieved between normal and tumor tissue.

Brachytherapy↗
PubMed1996

An analysis of mandibular bone complications in radiotherapy for T1 and T2 carcinoma of the oral tongue.

PURPOSE: To examine the incidence of mandibular bone complication in patients who underwent radiotherapy for T1 and T2 carcinomas of the oral tongue and to analyze the factors contributing to its occurrence. METHODS AND MATERIALS: The clinical records of 148 patients with T1 and T2 carcinoma of the oral tongue treated with radiotherapy alone between 1978 and 1989 were examined retrospectively. Interstitial brachytherapy, used as the major treatment modality, was performed using cobalt needles, radium needles, or iridium hairpins. The prescribed dose at the plane 5 mm from the plane of the radioactive sources was 65-70 Gy in interstitial brachytherapy alone, and 50-60 Gy in the combined treatment with external irradiation. An external irradiation dose of 30 Gy was usually used. RESULTS: Eleven of the patients showed radiation-induced mandibular bone complication. Two (1 T1, 1 T2) had been treated with interstitial brachytherapy alone, and nine (2 T1, 7 T2) with the combination of external irradiation and interstitial brachytherapy. The incidence of radiation complication of bone was significantly higher in the patients with T2 tumors (p = 0.04) and in those who received the combined treatment (p < 0.01). Multivariate analysis revealed that the total dose (p = 0.04) and dose rate of interstitial brachytherapy (p = 0.03) were significant factors contributing to radiation bone complication. A significant difference in the incidence of bone complication was also seen between patients who received a total dose of 90 Gy or more and those who received less than 90 Gy (p < 0.01), as well as between patients who were treated with 0.55 Gy/h or higher and those who were treated with less than 0.55 Gy/h (p = 0.03). CONCLUSION: A significant increase in the incidence of bone complication was found at the total dose of 90 Gy or more and at the dose rate of 0.55 Gy/h or higher. In combined treatment with external irradiation and interstitial brachytherapy, the interstitial brachytherapy dose of 60 Gy appears to be the threshold at which mandibular bone complication is induced when the external irradiation dose is 30 Gy.

Adult↗
PubMed1987

Template-guided interstitial implants: Cs-137 reusable sources as a substitute for Ir-192.

Template-guided implantation of rigid steel or plastic guide needles for afterloading of radioactive sources is widely used in the treatment of gynecologic, rectal, and urologic malignant neoplasms. Iridium-192 is used almost universally, despite the high cost per implant, due to its short half-life and limited need for a flexible, trimmable source. A reusable afterloading system containing cesium-137 was developed. Each source has an effective active length of 6.8 cm and is encapsulated at the distal end of a 21-cm-long stainless steel tube. The sources can be afterloaded into the same plastic guide needles normally used for Ir-192 ribbons. Physical and dosimetric aspects of these sources are compared with those of Ir-192, and radiation protection and cost effectiveness are also discussed.

Brachytherapy↗