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The main difficulty in the irradiation of retinoblastoma has been to deliver a high uniform dose to the entire retinal surface and spare the lens. Conventional techniques are inadequate to deliver an acceptable dose distribution especially for cases when there are both anterior and posterior lesions. We have developed a procedure to deliver a high dose anteriorly at the ora serrata for a compromise of about 30-35% of the target dose to the lens. The technique consists of 3 pairs of non-coplanar arcs using a 4 MV accelerator. This technique may offer a higher probability of tumor control and cure when gross tumor is present at the ora serrata when compared to the conventional techniques using lateral techniques.

A technique for assessing the overall consequences of disease is introduced, comprising a Swedish version of a behaviour-based measure, the Sickness Impact Profile (SIP). Measurement characteristics of the profile are defined in an epidemiological study of 147 women with rheumatic disorders. The drop-out rate was 7.5%. Cross-cultural evidence of the validity of the SIP was obtained in this study. Test-retest reliability was substantial. A high level of validity of the Swedish version was demonstrated, as assessed by hypothesized significant relationships with selected functional, psychological, and social correlates. The profile was able to describe the various sickness impacts in a specific and sensitive manner. In the epidemiological setting, the subscales representing Ambulation, Body care and movement, Emotional behaviour, Social interaction, Sleep and rest, Home management and Recreation and pastimes, all showed discriminatory capacity. The categories Mobility, Alertness behaviour, Communication, Work, and Eating discriminated less well. The response pattern was recognizably related to rheumatic complaints, emphasizing a broader applicability of this scale in rheumatology.

Rotational arcs covering less than 360 degrees are frequently used in order to spare critical structures in radiation therapy; however, this results in a lack of dose uniformity in the target volume. Wedge filters can be used to restore dose uniformity in the treatment volume when limited arcs are employed. The authors emphasize the use of small rotational arcs (less than 90 degrees) in treating eccentrically located tumors such as those of the spinal cord and describe a simple model which can be used to calculate the wedge angle as a function of the arc angle.