Applications
ISORAD diode detectors can be used in any situation where a surface mounted diode is needed to verify patient dose.
ISORAD diode detectors are particularly useful for tangential treatments where the angle of incidence is difficult or impossible to predict.
ISORAD diode detectors can be used in conjunction with some solid phantoms and the IVD™ to verify complex treatment plans.
Energy Ranges – choosing the right ISORAD
ISORAD detectors are offered in three photon energy ranges. A single
energy compensted detector is also offered.
| a) P/N 1162000-2 | 1-4 MV | |
| b) P/N 1163000-2 | 6-12 MV | |
| c) P/N 1164000-2 | 15-25 MV | |
Accuracy
The ISORAD offers exceptional accuracy.
When tested in air or in a cylindrical phantom for all the beams:
Variation in Axial response is only +/- 0.5%
from 0° ~ 360°
When tested on top of 6 cm of solid or
virtual water:
Variation in Axial response is still only +/- 0.5% from -60°
~ 60° for 6 MV
Variation in Axial response is only +/- 1.0% from -60° ~ 60°
for 18 MV
Axial Directional response of ISORAD detectors on the Phantom
Side view of ISORAD photon detector (all dimensions in mm)
For a technical comparison against the MOSFET detector, click here.
Lifetime
As with any diode, ISORAD sensitivity will gradually change over time.
This rate of change will depend on the energies used and the frequency of
use. For normal use, plan on re-calibration once per year. Note that ISORAD
life expectancy is not limited by radiation exposure – in fact the more an ISORAD is used the less its response characteristics will change. Life
expectancy is an issue of proper handling and care. Broken coaxial connectors
and cables are the most common cause of failure. When handled under normal
stress loads, the ISORAD should be expected to last > 1,000,000 cGy.
Construction
ISORAD construction is an advanced third-generation design. Build-up
consists of a material that is best suited for each energy range.
Features
ISORAD is the only available diode with Cylindrical Symmetry, angular
corrections are not required.
Advanced n-type die design is accurate.
Compatibility with any diode based dosimetry system.
Very good reproducibility (≤ 1% for measurements >1 cGy)