Philips Azurion - Field Size

Paent T
ype Weight
Large Adult 70 - 90 kg
Very Large Adult >90 kg
The table above provides guidance for manual paen
t type selecon. You can also select the Automac
paent type. In this case the system automacally selects an appropriate paent type for each study
based on the paent's age, height, and weight, which can be entered while scheduling the paent.
For some applicaons and procedures, the dose sengs are equal for all paent types. In these cases
the automac dose control mechanism manages all depths of irradiated ssue without loss of image
quality, and the paent type selecon has no eect on the reference air kerma (rate). Examples are:
uoroscopy, roadmap, and vascular peripheral. The sengs for the default paent type are used if no
specic X-ray protocols are dened for the selected paent type.
For other applicaons and procedures, the paent type selecon will inuence the reference air kerma.
See the following example for cardiac procedures:
System Paent T
ype Ref. AK (mGy/img)
C12/F12
• Cardiac procedure
• Le Coronary
• 15 fps Normal
Neonate 0.041
Infant 0.074
Child, Small Adult 0.117
Default 0.196
Large Adult, Very Large Adult 0.197
C12/F12
• Pediatrics procedure
• Pediatric
• 15 fps Normal
Neonate 0.043
Infant 0.074
Child, Small Adult 0.115
Default 0.195
Measurement c
ondions: eld size: 30 cm. All other sengs in accordance with Reference Air Kerma
Measurement Setup (page 311).
For more informaon about the inuence of paent thickness on the air kerma, see Inuence of
Oblique Projecons (page 293).
Field Size
In general, the requested detector dose needs to be larger for smaller eld sizes to compensate for
increasing perceived noise at smaller eld sizes. Therefore, the air kerma and air kerma rate will be
larger for smaller eld sizes.
NOTE Consider zooming uorosc
opy images with appropriate collimaon, instead of using a small
eld size. Digital zooming does not inuence the air kerma.
NOTE Unlike air kerma, dose area product decreases at smaller eld sizes, so using a small eld size
decreases the risk of stochasc eects. For example, for pediatric procedures, a small eld
size may be more appropriate.
For every uoroscopy avor and every exposure X-ray protocol a programmable dose rao per eld size
and per X-ray plane is available. The dose rao indicates per available eld size the percentage detector
dose increase, compared to the detector dose at the largest eld size.
In the examples below, reference air kerma increases approximately proporonally with the dose rao
numbers. The same applies to reference air kerma rate for uoroscopy.
The following example gives the reference air kerma values for a vascular procedure for dierent eld
size values on C12/F12 systems.
Technical In
formaon System Sengs Inuencing the Radiaon Dose
Azurion Release 1.2 Ins
trucons for Use 291 Philips Healthcare 4522 203 52421