Smartphone and custom-made software to assess the effect of botulinum toxin in essential blepharospasm: Initial results.

Assessment of the spontaneous eyelid movements obtained with the smartphone camera and analysed with the custom-made software enabled us to objectively measure the therapeutic effects of botulinum toxin in patients with blepharospasm. Further refinement of this system could enable customized and fine adjustments to botulinum toxin doses based on each patient's needs.