<unk>  is also known as "ice-pick headache", is a primary headache disorder, so it is not caused by any other conditions.
Ophthalmodynia periodica
Oculomucocutaneous syndrome
Floppy eyelid syndrome
Oculoauricular syndrome
Rectovestibular fistula
Vulvar vestibulitis
Nasal vestibulitis
Vestibular adenitis