Is 1mm needle size for microneedling safe to use under the eyes?

The depth of the needle depends on the patient and area being treated. Normal depth for facial microneedling is 0.75 - 1.5 mm.  I always recommend microneedling with PRP for best results. I often combine these procedures with fillers, on the same day when treating under the eye. See an expert. Best, Dr. Emer

In my opinion, microneedling is not the correct treatment for undereye dark circles or visible undereye veins. Depending on the cause of the undereye dark circles, fillers may help. The veins would need to be treated with a vascular laser such as the V Beam or Excel V.