Embodiments of the invention are related to header assemblies for implantable medical devices, amongst other things. In an embodiment the invention includes a medical device including a header assembly housing. The header assembly housing can include a dielectric material, the header assembly housing can define a port aperture for receiving a connector pin of a stimulation lead. The port aperture can have a first end and a second end and a reflective insert disposed within the header assembly housing proximate to the second end. The reflective insert can be configured to enhance the view of the second end from outside of the header assembly housing. Other embodiments are also included herein.