Is there a need for attenuation correction in the 99mTc-DMSA scans on pediatric...

• Author(s): Nogueira, Fábio ; Lemos, Joana ; Oliveira, Marta ; Silva, José A. ; Sousa, Maria C. ; Cunha, Lídia ; Metello, Luís F.
• Date: 2010
• Persistent ID: http://hdl.handle.net/10400.22/2364
• Origin: Repositório Científico do Instituto Politécnico do Porto
• Document Type: Lecture
• Language: English

Description

Introduction: The quantification of th e differential renal function in adults can be difficult due to many factors - on e of the se is the variances in kidney depth and the attenuation related with all the tissue s between the kidney and the camera. Some authors refer that t he lower attenuation i n p ediatric patients makes unnecessary the use of attenuation correction algorithms. This study will com pare the values of differential renal function obtained with and with out attenuation correction techniques . Material and Methods: Images from a group consisting of 15 individuals (aged 3 years +/ - 2) were used and two attenuation correction method s were applied – Tonnesen correction factors and the geometric mean method . The mean time of acquisition (time post 99m Tc - DMSA administration) was 3.5 hours +/ - 0.8h. Results: T he absence of any method of attenuation correction apparently seems to lead to consistent values that seem to correlate well with the ones obtained with the incorporation of methods of attenuation correction . The differences found between the values obtained with and without attenuation correction were not significant. Conclusion: T he decision of not doing any kind of attenuation correction method can apparently be justified by the minor differences verified on the relative kidney uptake values. Nevertheless, if it is recognized that there is a need for a really accurate value of the relative kidney uptake, then an attenuation correction method should be used.