Table 1 Summary of the detectors currently available [5, 16,17,18,19]
From: Preclinical dosimetry: exploring the use of small animal phantoms
Detector | Specifications | Advantages | Disadvantages |
|---|---|---|---|
Ionisation chambers | • Commissioning • Dose calibration • QA • Uncertainty: < 5% • Dose: up to 1000Gy | • High precision and accuracy • Various models, including waterproof models • No effect from dose rate • Instant readout | • Requires high voltage • Size • Elaborate care |
Radio-graphic Film | • Imaging • Dosimetry • Phantom compatible • Uncertainty: < 5% • Dose: 0.1-5Gy | • Great spatial resolution • 2D dose distribution • No effect from dose rate • Various film types • Useful for assessing field size, flatness and symmetry | • Complex processing • Film type/batch variation • Dose calibration required • Affected by energy • Light sensitive • Not reusable |
Radio-chromic Film | • Imaging • 2D Dosimetry • Phantom compatible • Uncertainty: < 5% • Dose: 0.1-200Gy | • Self-processing • Tissue-equivalent • No effect from dose rate/energy • Great spatial resolution • Useful for radiation field size, flatness and symmetry | • Results vary between film types and batches • Dose calibration required • Not reusable • Requires stabilisation period after irradiation |
TLDs | • In vivo dosimetry • Phantom compatible • Audit purposes • Uncertainty: < 5% • Dose:<200Gy | • Small size • Multiple point readings • Various models available • Reusable | • Laborious calibration • Delayed results • Signal erased during readout • Results vary between batch • Light sensitive |
OSLDs | • In vivo dosimetry • Phantom compatible • Audit purposes • Uncertainty: < 4% • Dose: <10Gy | • Moderate size • Multiple point readings • Quick readout • No effect from dose rate | • Light sensitive • Limited availability • Not suitable for calibration • Energy dependent |
Silicon Diodes | • In vivo dosimetry • Detector arrays • Dosimetry • Uncertainty: < 3% • Dose: <10Gy | • Moderate size • Instant readout • Good sensitivity • No external voltage • Small field dosimetry | • Requires connecting cables • Temperature sensitive • Unsuitable for calibration • Unsuitable at higher doses |
MOSFETs | • In vivo dosimetry • Small field dosimetry • Detector arrays • Uncertainty: < 5% • Dose: <10Gy | • Small size (0.2 × 0.2 mm) • Multiple point readings • quick readout • Good sensitivity | • Calibration required • Energy, temperature and directional dependent • Unsuitable for calibration |
Diamond Detectors | • In vivo and small field dosimetry • Uncertainty: < 3% • Dose: <10Gy | • Small size • Tissue-equivalent • High sensitivity • Resistant to radiation | • External equipment required • Requires pre-irradiation • Results vary among detectors • Unsuitable for calibration |
Alanine – Electron para-magnetic resonance | • In vivo dosimetry • Phantom compatible • Audit purposes • Uncertainty: < 4% • Dose: 10-150000Gy | • Tissue-equivalent • Readout process does not diminish signal | • Readout requires specific equipment |
Gel dosimetry detectors | • 3D dosimetry • Audit purposes • Uncertainty: 5–10% • Dose: <10Gy | • Tissue-equivalent • Both phantom and detector • 3D dose distribution | • Elaborate preparation • Continued processing • Difficult reproducibility • Unsuitable for calibration |