  The purpose of the present work is the study of reconstruction properties of
a new Molecular Breast Imaging (MBI) device for the early diagnosis of breast
cancer, in Limited Angle Tomography (LAT), by using two asymmetric detector
heads with different collimators. The detectors face each other in
anti-parallel viewing direction and, mild-compressing the breast phantom, they
are able to reconstruct the inner tumour of the phantoms with only a limited
number of projections using a dedicated maximum-likelihood expectation
maximization (ML-EM) algorithm. Phantoms, MBI system, as well as Monte Carlo
simulator using Geant 4 Application for Tomographic Emission (GATE) software,
are briefly described. MBI system's model has been implemented in IDL
(Interactive Data Visualization), in order to evaluate the best LAT
configuration of the system and its reconstruction ability by varying tumour's
size, depth and uptake. LAT setup in real and simulated configurations, as well
as the ML-EM method and the preliminary reconstruction results, are discussed.
