I wear glasses and I have yet to find a pair of sufficiently isolating headphones that doesn't become painfully uncomfortable after 1 hour. And I've tried various high-end solutions.
Tried Etymotic earbuds? They come with a bunch of adapters to fit different sized ears. My model is of course discontinued but the mc5 looks closest. http://www.etymotic.com/ephp/mc5.html
edit: unlike any other earbuds I have tried, they are engineered to survive the inevitable wax-plugging. Just replace the filter & you're back in business.
I tried industrial earmuffs for a while (-25 dB), when I was in a noisy office, and they work. With another "layer" of in-ear phones you can work anywhere. They also send a stronger signal of "don't bother me", but some will find it rude.