An optical coupler is disclosed with an attachment section for mounting at a distal end of an optical imaging device for visualizing a surface area covered with an opaque fluid and/or particulate matter. The coupler includes a visualization section at one end of the coupler that includes a proximal surface for engaging the distal end of the optical imaging device, an attachment section connected to and extending away from the visualization section, an outer surface spaced apart from the proximal surface, and may include a hollow instrument channel extending from the proximal surface toward the outer surface. This surface extends continuously from a first outer side boundary across to a second opposite outer side boundary of the visualization section. The visualization section can be formed from an elastic material capable of transmitting an optical image of the surface area. In one form, the material is a silicone gel or elastomer.