Imaging ``Pinwheel'' nebulae with optical long-baseline interferometry

Dusty Wolf-Rayet stars are few but remarkable in terms of dust production rates (up to Ṁ = 10^-6 M_solar/yr). Infrared excesses associated to mass-loss are found in the sub-types WC8 and WC9. Few WC9d stars are hosting a ``pinwheel'' nebula, indirect evidence of a companion star around the primary. While few other WC9d stars have a dust shell which has been barely resolved so far, the available angular resolution offered by single telescopes is insufficient to confirm if they also host ``pinwheel'' nebulae or not. In this article, we present the possible detection of such nebula around the star WR 118. We discuss about the potential of interferometry to image more ``pinwheel'' nebulae around other WC9d stars.