  We analyze the quantization of the Pais-Uhlenbeck fourth order oscillator
within the framework of deformation quantization. Our approach exploit the
Noether symmetries of the system by proposing integrals of motion as the
variables to obtain a solution to the -genvalue equation, namely the Wigner
function. We also obtain, by means of a quantum canonical transformation the
wave function associated to the Schr\"odinger equation of the system. We show
that unitary evolution of the system is guaranteed by means of the quantum
canonical transformation and via the properties of the constructed Wigner
function, even in the so called equal frequency limit of the model, in
agreement with recent results.
