Home  About us  Contact
 

External Radiation (external + radiation)

Distribution by Scientific Domains
Medical Sciences75%

Terms modified by External Radiation

  • external radiation therapy
    		•

    Selected Abstracts

    Surface temperature measurements on burning materials using an infrared pyrometer: accounting for emissivity and reflection of external radiation

    FIRE AND MATERIALS, Issue 1 2004
    Joe Urbas
    Abstract This paper demonstrates the successful use of an infrared pyrometer, operating in the 8,10 µm wavelength band, to measure the surface temperature of combustible specimens in a heat release calorimeter. The temperature histories of ten different materials were measured in the ICAL (intermediate scale calorimeter). The set of materials comprised four wood products, gypsum board, polyisocyanurate foam, PVC floor tile, PMMA and two non-combustible boards. A small-diameter bare thermocouple was installed on each specimen in order to determine an accurate temperature for comparison. The spectral emissivity and the spectral flux reflected from the surface were measured simultaneously and used to correct the apparent temperature measured by the pyrometer. The spectral emissivity and reflected spectral flux were both constant prior to ignition for all the combustible materials. During the burning phase all the combustible materials had a spectral emissivity very close to unity. The agreement between the temperatures measured with the pyrometer and thermocouple was not affected by the flame. The wood products, the polyisocyanurate foam and the calcium silicate board required no correction for reflected spectral flux over the whole temperature range. Copyright © 2004 John Wiley & Sons, Ltd. [source]

    "FAR" chemoradiotherapy improves laryngeal preservation rates in patients with T2N0 glottic carcinoma,

    HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 7 2002
    Yoshihiko Kumamoto MD
    Abstract Background The appropriate treatment approach for patients with T2N0 laryngeal cancer remains highly controversial. Because radiotherapy alone is associated with a high risk of local recurrence, we have developed a triple combination treatment approach consisting of 5-fluorouracil (250 mg/day, i.v.), vitamin A (50,000 unit/day, i.m.) and external radiation (2.0 Gy/day), which we have termed "FAR therapy." Methods Patients with T2N0 glottic carcinoma were initially treated with 15 days of FAR therapy, which included a cumulative radiation dose of 30Gy (i.e., "30 Gy of FAR therapy"). Those patients who demonstrated a complete response either clinically or pathologically continued to receive further FAR therapy, with up to 60,70 Gy. All other patients received laryngectomy without any additional treatment. Results Ninety-five patients were treated according to this program, and most of the patients (98%) were able to complete this treatment course. Eighty-eight patients (93%) were treated with FAR therapy alone. The local control and ultimate local control rates were 91% (85 of 93), and 99% (92 of 93), respectively. The cumulative 5-year voice preservation and complete laryngeal preservation rates were 91% and 87%, respectively. The cumulative 5-year disease-specific survival rate was 97%. Conclusions Because a high rate of laryngeal preservation was achieved without compromising disease-specific survival, our treatment approach based on FAR therapy may be promising for the treatment of patients with T2N0 glottic carcinoma. © 2002 Wiley Periodicals, Inc. [source]

    Health outcomes of children fathered by patients treated with radioiodine for thyroid cancer

    CLINICAL ENDOCRINOLOGY, Issue 6 2009
    Jérôme-Philippe Garsi
    Summary Context and objectives, Radiation is known to be mutagenic. The present study analyses birth outcomes and the health of offspring from men previously exposed to 131I treatment for thyroid carcinoma. Methods, Data on 493 pregnancies (356 from 173 untreated fathers, 23 from 17 patients who have undergone surgery alone and 114 from 63 fathers who received 131I) were obtained by interviewing male patients treated for thyroid carcinoma who had not received significant external radiation to the testes. Among these pregnancies, 73 were conceived from fathers who had received more than 370 MBq. Results, The mean activity for the 114 pregnancies fathered by 63 patients was 3993 MBq leading to an estimated radiation dose of 9·2 cGy to the testes (MIRD committee coefficient). No significant differences between untreated and treated fathers were found for any adverse outcome. Conclusion, There was no evidence that exposure to radioiodine affects the outcome of subsequent pregnancies and offspring, whatever the event considered. As our study is underpowered, the question of whether testicular irradiation, fractionated or not, is linked to impaired fertility or consequences on offspring remains to be established. [source]

    The prognostic value of lymph node metastases and tumour regression grade in rectal cancer patients treated with long-course preoperative chemoradiotherapy

    COLORECTAL DISEASE, Issue 3 2009
    J. Lindebjerg
    Abstract Objective, The purpose of the present study was to investigate the impact of tumour regression and the post-treatment lymph node status on the prognosis of rectal cancer treated by preoperative neoadjuvant chemoradiotherapy. Method, One hundred and thirty-five patients with locally advanced T3 and T4 rectal tumours received preoperative long-course chemoradiation, to a dose of 60 Gy external radiation and oral 5-fluorouracil 300 mg/m2 daily and Leukovorin 22.5 mg/day 5 days a week. Surgery was performed 8 weeks after the end of treatment. The tumour response was evaluated according to the tumour regression grade system and lymph node status in the surgical specimen was assessed. The prognostic value of clinico-pathological parameters was analysed using univariate analysis and Kaplan,Meier methods for comparison of groups. Results, All patients responded to treatment and 47% had a major response, including 25 (19%) complete responders. The median follow-up was 26 months (range 12,94 months). The cancer specific survival was 82% and there was a significant lower survival rate in the group of patients with post-treatment lymph node metastases compared to lymph-node negative patients [63% and 87% respectively (P = 0.007)]. Furthermore patients with a major tumour response and no lymph node metastases in the surgical specimen after treatment had a survival rate of 100% compared with 60% in the group of patients with major response but lymph node metastases after surgery (P < 0.01). Conclusion, The combined assessment of lymph-node status and tumour response has strong prognostic value in locally advanced rectal cancer patient treated with preoperative long-course chemoradiation. [source]