of 27 /27
Klinisk strålebiologi - normalvev

# Klinisk strålebiologi - normalvev

Tags:

• #### treatment options

Embed Size (px)

DESCRIPTION

Klinisk strålebiologi - normalvev. Tidlig reaksjon. Sen reaksjon. teleangiectasi. Basis for dose-respons-kurver. Stigetallet for dose-responskurven. Gaussian distribution of radiation sensitivity. Gaussian distribution of technical and dosimetrical factors. - PowerPoint PPT Presentation

### Text of Klinisk strålebiologi - normalvev

• Klinisk strlebiologi - normalvev

• Tidlig reaksjon

• Sen reaksjonteleangiectasi

• Basis for dose-respons-kurver

• Stigetallet for dose-responskurven

• Gaussian distribution of radiation sensitivityDose response curve

Uniquely described by two parameters: - gradient at 50% response levelD50% - dose to achieve 50% response

Gaussian distribution of technical and dosimetrical factorsbiolo > clin Pettersen M et al Radiotherapy and Oncology 2008Clinical dose response curve

• Uniquely described by two parameters: - gradient at 50% response levelD50% - dose to achieve 50% response

is linked to the standard deviation, , of the Gaussian distribution by: Pettersen M et al Radiotherapy and Oncology 2008and

• Steepness of clinical dose-response curve is depending of the dose variationPettersen M et al Radiotherapy and Oncology 2008Rou et al 2004ESTRO-Equal external audit102 centres, 235 beams in France3% beams had deviations > 5%24 centres had deviations > 5%

• Design of a randomised clinical study The null hypothesis is that the two treatment options produce no different outcome To prove a difference, the null hypothesis has to be rejected The number of patients needed is linked to , the difference in response (R), the level of significance () and the power () = 0.2 = 0.05Pettersen M et al Radiotherapy and Oncology 2008

• The number of patients requiredConclusions:To keep the number of patients required for RCT as low as possible, the standard deviation of the dosimetry should be kept below 5%.

• Volumeffet for rektumbldning

• Strandqvist plot

• LQ-formelverket

Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents
Documents