Osaki MH, Osaki TH, Garcia DM, Osaki T, Gameiro GR, Belfort R Jr, Cruz AAV. An objective tool to measure the effect of botulinum toxin in blepharospasm and hemifacial spasm. Eur J Neurol 2020 Apr 15. doi: 10.1111/ene.14258. Online ahead of print.
It is challenging to assess patients with blepharospasm (BSP) and hemifacial spasm (HFS) as these patients exhibit anomalous eyelid movements with a wide range of amplitudes. In order to objectively assess the therapeutic effects of botulinum toxin (BoNT) in these patients, we evaluated the energy generated by the upper eyelid during spontaneous eyelid movements before and after treatment. In order to quantify these movements, a mathematical algorithm (Fast Fourier Transform) was employed to convert the signal from the time domain to the frequency domain. The result of this quantification represents the energy generated during the eyelid movements. We studied 78 eyelids. The total energy generated during spontaneous eyelid movements was significantly reduced after treatment in the patients with BSP (P = 0.0018) and on the affected side in the patients with HFS (P = 0.0058). The assessment of the energy generated by the upper eyelid during spontaneous eyelid movements enabled us to measure the therapeutic effects of BoNT in patients with these conditions. The use of this system could enable customized and fine adjustments to BoNT doses based on each patient’s needs.
Dr. Midori Osaki
Ophthalmologist - CRM-SP 38.981
Midori Hentona Osaki, Head of the Oculoplastic Sector, Department of Ophthalmology and Visual Sciences, Escola Paulista de Medicina/Universidade Federal de São Paulo - EPM/UNIFESP (2005-2016). Secretary at SBCPO (2015-2017); Deputy Secretary at SBCPO (2017-2019); Member of the Brazilian (SBCPO), American (ASOPRS) and Asia-Pacific Oculoplastic (APSOPRS) Societies.
