The present disclosure describes a dressing for use in a vacuum wound therapy procedure and system to promote healing of a wound. The dressing includes a cover layer for positioning over a wound to define a reservoir in which a reduced pressure may be maintained over the wound. A portal member is mounted relative to the cover layer and defines a fluid passage for fluid coupling with a reduced pressure supply conduit for creating the reduced pressure within the reservoir. A filter screen is mounted relative to the fluid passage and is dimensioned to minimize passage of tissue particles of predetermined dimension through the fluid passage of the portal member.
