Aims and objectives
Registering and reducing patient radiation dose is a hot topic in modern radiology [1-2].
Awareness of the malignant effects of ionizing radiation is growing,
especially for pediatric populations [3-4].
An increasing number of hosptials are now starting toemploy user-friendly dose monitoring software,
such as DoseWatch.
This interface is used for capturing and tracking radiation doses for different imaging modalities,
and alert the technicians when an excessive amount of radiation was used...
Methods and materials
As shown in the left panel of Fig.
the lumbar spine CT Dose Length Product (DLP) plotted against the patients BMI,
fits an exponential curve. Using the following transformation: y=exp(a.x) ==> Ln(y)=a.x where 'a' is a real number and x and y are variables (in this case BMI and DLP),we transform the exponential curve into a linear dependency. Afterthis,
we can perform a simple linear regression through the transformed data.Next,
we determinea newalert threshold based on the residuals,
The left panel of Fig.
shows the dataset of 156 lumbar spine procedures which is considered in this study.
The 34 highest doses result in an alert,usingthe oldthresholding-methodof exceeding2 times themedian DLP.The high dose was in most cases justified by the high BMI of the patient.
The minimum BMI of an alert triggering patient was 27 kg/m². We determined a new alert thresholding-method based on a logarithmic transformation of the data.The right panel of Fig.3 shows the alerts triggered...
The proposed method tackles the issue of the BMI dependency of thehigh-dose alert-triggeringin certain procedures such as lumbar spine and abdomen. The question is now asked: " has the patient received a high radiation dose in proportion to his or her posture ?" The alerts now contain a higher relevancy than before. Limitations: The method described above does have some limitations and basic assumptions,
which are not necessarily met. First of all there is no theoretical underpinning of the...
Reducing body CT radiation dose: beyond just changing the numbers.
AJR American journal of roentgenology.
Epub 2013/06/26. 2.
[Modern techniques for dose reduction in computed tomography imaging].
Moderne techniken zur strahlendosisreduktion in der computertomographie. 3.
Computed tomography--an increasing source...