Disclosed herein is a method of examining tissue growth and/or conditioning and/or adhesion properties of cells on a synthetic and/or natural scaffold (30) as well as a perfusion bioreactor (10) for use in this method. The method comprises the following steps: fixing a scaffold (30) to a holding means (28) disposed or disposable in a perfusion bioreactor (10), generating a flow of nutrition solution along the surface of said scaffold (30) held by said holding means (28), generating and/or maintaining physiological conditions in said nutrition solution flowing along said scaffold (30) using heat exchange means (20, 24, 48, 50) and/or gas exchange means (52, 54, 56, 58, 60, 62, 64) associated with said bioreactor (10), such as to allow growth and/or conditioning of cells on said scaffold (30), and optically inspecting, in particular by microscopy, the scaffold (30) held by said holding means (28) through a window (66, 68, 70, 72) provided in said perfusion bioreactor (10) at different times or continuously during tissue growth and/or conditioning of cells on said scaffold (30) while maintaining said physiological conditions in said perfusion bioreactor (10).