  LS I +61 303 has been recently detected as a periodic gamma-ray source by the
Major Atmospheric Imaging Cerenkov (MAGIC) telescope. A distinctive orbital
correlation of the $\gamma$-ray emission was found. This work shows that the
range of uncertainties yet at hand in the orbital elements of the binary system
LSI as well as in the possible assumptions on the stellar wind of the optical
companion play a non-negligible role in the computation of opacities to high
energy processes leading to $\gamma$-ray predictions. The geometry influence on
the propagation and escape of $\gamma$-ray photons is explored. With this study
at hand, we analyse the results of a pulsar wind zone model for the production
of gamma-rays and compare it with recent MAGIC observations.
