William Gibson explains how Molly's mirrorshades work

The image of Molly Mirrorshades' implanted sunglasses, as seen in William Gibson's pioneering cyberpunk novel Neuromancer, is the most canonical cyberpunk eyeball kick in the field, the template for all that is cyber-cool. But how, exactly, do implanted shades work? Gibson himself has posted some pithy, geeky thoughts on the subject, 22 years after the publication of Neuromancer.
With Molly Millions' "implanted" glasses, though, I could never dream up a sufficiently convincing way to imagine them being attached. Were they "implanted" in skin, muscle, bone, all of these? How would any of these impact on the mobility of her features? What would the seam between skin and mirror look like?

The character having emerged, very handily, in an early short story, when I hadn't been much concerned with this particular detail, and not having expected to see her again, I found myself, as more Molly narratives emerged, concerned by my inability to satisfactorily envision the way in which the damned things were attached. My solution to this, ongoing, was to keep the "camera" off that troubling little detail. To blur around it with language. The "mirrored implants" worked wonders for the character, in fact largely *were* the character, but there was never, really, any "really" there.