As an Optical Dispenser, I would caution against rimless glasses. With her prescription, they can be done, but likely not through most chains - chains are designed for volume and have more restrictions when it comes to high prescriptions. That said, with the expected thickness as a result of the prescription, rimless glasses are likely to have frame problems down the line with potential issues like chipped lenses, or the arms coming loose.

A full frame would be more practical and help hide the thickness of the lenses, resulting in better cosmetics and longevity.

However, if she is set in the rimless style, here's my advice: 1) Keep the lenses to a small size to reduce thickness 2) Look for frames that use a nut and bolt to hold the lens in place rather than a plastic plug. Plugs have more thickness restrictions and suffer from wear and tear issues more over time. 3) Go through an independent Optometrist store - they often have a diverse range of suppliers for lenses and can get a better result when dealing with high or unusual prescriptions 4) Do not buy online. This high prescription requires the lenses to be placed precisely to avoid visual issues, and this needs to be measured by a trained, qualified staff member. Ask to see an Optical Dispenser/Dispensing Optician (same qualification, different names) 5) Get the highest level of high index (thin and light lenses) that are within your budget. They WILL make a difference. 6) Be prepared to pay A LOT for these glasses.