Biotin is generally considered safe, even with glaucoma. I know a glaucoma specialist who has recommended biotin (along with other supplements) to his patients.
As a group, the B vitamins support brain health and memory, and may help form a defense against cognitive issues and neurodegenerative disorders such as glaucoma and Alzheimer's disease.
According to most sources, the main neuroprotective B vitamins are B1, B6 and B12. In the nervous system.
B Vitamins in the nervous system: Current knowledge of the biochemical modes of action and synergies of thiamine, pyridoxine, and cobalamin - PMC
Neurotropic B vitamins play crucial roles as coenzymes and beyond in the nervous system. Particularly vitamin B1 (thiamine), B6 (pyridoxine), and B12 (cobalamin) contribute essentially to the maintenance of a healthy nervous system. Their importance is highlighted by many neurological diseases related to deficiencies in one or more of these vitamins, but they can improve certain neurological conditions even without a (proven) deficiency.
The above paper barely mentions biotin in relation to nerves. However, the next paper presents very interesting information that deserves more attention and potentially suggests biotin (along with the other B vitamins) could be a prudent supplement for those of us living with glaucoma.
Biotin: From Nutrition to Therapeutics - PMC
High doses of biotin (100–300 mg/d) were tested.
In 4 patients with prominent visual impairment related to optic nerve
injury, visual acuity improved considerably, and visually evoked
potentials improved in 2 patients. Proton magnetic resonance
spectroscopy in 1 patient showed an improved choline:creatine ratio.
One patient with left-sided blindness for both eyes steadily improved
from 2 to 16 mo of biotin supplementation. Of the 18 patients with
prominent spinal cord involvement, 16 improved; a blinded review of a
videotaped clinical examination was possible for 9 patients and
confirmed improvement in all of them. Preliminary results from
multicenter double-blind placebo-controlled trials in Europe and the
United States are encouraging