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M P Casebow

Publications and source records attributed to M P Casebow.

15 recordsLinked to original sources
PubMed2002

A pragmatic approach to dosimetric audit in radiotherapy.

In 1993 a dosimetric audit programme was initiated by physicists from a group of hospitals in the South West UK with the aim of detecting dosimetric errors greater than 5%. The scope of this programme was developed to cover megavoltage and kilovoltage photons as well as electrons. Procedures operated within each department were also audited in situations where they could influence dosimetry. No dose discrepancies greater than 5% were detected in the course of the audits, though differences did correlate with complexity in some situations. These measurements provide an ongoing assurance that dosimetry within the participating centres is well controlled and provides a firm foundation for clinical practice.

Electrons↗
PubMed1998

The use of an optical outlining system for weekly on-set verification of patients with carcinoma of the breast.

The installation of an optical outlining system on both a simulator and treatment unit has enabled patient cross-sectional outlines to be measured throughout a radical treatment period of 5 weeks. Two studies were conducted to assess the reproducibility of positioning in treatments for breast carcinoma. The first study assessed changes in outline for 23 patients treated on a home-made tilt-board. Seven patients (32%) displayed a change in shape in excess of 1 cm during the course of treatment, which could have significant dosimetric consequences. The second study focused on the reproducibility of set-up using different tilt-boards. This included a further 19 patients treated using a commercial board, which is now in routine use.

Adenocarcinoma↗
PubMed1990

A modified synchronous shielding technique in rotation therapy.

Synchronous shielding in rotation radiotherapy involves the movement of an absorber across the X-ray beam profile during a rotation treatment. This procedure can shape the cross-section of a cylindrical treatment volume to avoid nearby radiosensitive structures but often produces unacceptable dose variations within the treatment volume. These effects may be reduced by modifying the dose rate profile of the beam using wedge-shaped filters attached to the absorbers. A mechanism is then required to orientate the absorbers and filters during the rotation. A prototype device was constructed and assessed experimentally using a 6 MV X-ray beam.

Humans↗