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Summary.-A method based upon the application of mathematical techniques of deconvolution on the classical compartmental model for the quantitative study of liver function from hepatobiliary scintigraphy using 99m Tc-mebrofenin data is proposed. The theory in which the method is based upon is presented and a comparison with a published methodology of obtaining the hepatic extraction after scintigraphic sudies has been performed using the results on 36 rats studies obtained with the two methods. A highly significant correlation between the two techniques was verified. The characterisitics of the two methodologies, the proposed one based upon a theoretical approach and the other one on an empirical approximation are discussed. Comments are made on the interest and limitations of the presented technique that may be an useful tool for the evaluation of hepatic insufficiency. Resumen.-Se propone un método basado en la aplicación de técnicas matemáticas de deconvolución sobre el modelo compartimental clásico para el estudio cuantitativo de la función hepática con datos de gammagrafía hepatobiliar con 99mTc-mebrofenina. Se presenta la teoría sobre la cual se basa el método y se hace una comparación con una metodología publicada para la obtención de la extracción hepática después de hacer estudios grammagráficos utilizando los resultados de 36 estudios en ratas, obtenidos con los dos métodos. Se comprobó una correlación altamente significativa entre las dos técnicas. Se discuten las características de las dos metodologías, la propuesta basada en un enfoque teórico y la otra en un enfoque empírico. Se comenta el interés y limitaciones de la técnica presentada que puede ser una herramienta útil para la evaluación de la insuficiencia hepática. PALABRAS CLAVES: Gammagrafía hepatobiliar. Análisis de deconvolución. Función hepática. INTRODUCTIONStudies of liver function based on scintigraphic data using compartmental modelling have been tried by several groups [1][2][3][4][5] . Results from these classical models are usually presented as rate constants for the hepatic extraction from the plasma and, in the case of hepatobiliary scintigraphy, also for the hepatic excretion. Other measured parameters are the disappearance half-life (T 1/2 ) and mean of the residence time for the radio-pharmaceutical molecules. The method proposed is based upon the application of mathematical techniques of deconvolution over the classical compartmental model. The quantification of parameters with physiologic meaning, in hepatobiliary scintigraphy may be obtained by using 99m Tc-mebrofenin. After a venous puncture this agent (or any of the last generation 99m Tc-IDA derivatives) is transported in blood mainly loosely bound to albumin. In the space of Disse, 99m Tc-mebrofenin is taken up by the hepatocyte and excreted into the intestine through the bile, without modifications 6 . This radio-pharmaceutical has high specificity for hepatocyte uptake (98 %), rapid blood clearance, fast intra-hepatic transit and no enteric absorption. Sixty minutes aft...

A B S T R A C TContinuing Professional Development (CPD) is vital to the medical physics profession if it is to embrace the pace of change occurring in medical practice. As CPD is the planned acquisition of knowledge, experience and skills required for professional practice throughout one's working life it promotes excellence and protects the profession and public against incompetence. Furthermore, CPD is a recommended prerequisite of registration schemes (Caruana et al. 2014 [4]. It is to be noted that currently not all national registration schemes require CPD to maintain the registration status necessary to practise medical physics. Such schemes should consider adopting CPD as a prerequisite for renewing registration after a set period of time.This EFOMP Policy Statement, which is an amalgamation and an update of the EFOMP Policy Statements No. 8 and No. 10, presents guidelines for the establishment of national schemes for CPD and activities that should be considered for CPD.