An analysis of facial blood perfusion in patients with peripheral facial palsy.

This study aimed to investigate the value of laser speckle contrast imaging in detecting facial blood perfusion in patients with peripheral facial palsy (PFP); to establish the evaluation criteria for facial blood perfusion; and to clarify the relationship between facial microcirculatory status, facial nerve function, and facial blood flow changes in PFP patients. Thirty healthy controls and 132 PFP patients receiving treatment at our hospital were chosen for laser speckle contrast imaging, in order to quantify their facial blood perfusion at the following 4 sites: the periocular region, the middle cheeks, the corners of the mouth, and the nasolabial fold. Blood perfusion values (BP) were measured for these sites, and the rate of blood flow changes was calculated as follows: R = (BPaffected side-BP healthy side)/BPhealthy side. The changes in blood flow rates in the periocular region and cheeks were significantly different between patients with severe peripheral facial paralysis (PFP) and healthy controls. However, no significant differences were observed at these sites between patients with Ramsay Hunt syndrome and those with Bell's palsy. In patients with moderate and severe PFP, the rate of blood flow changes in the periocular region was lower compared to healthy controls. Additionally, patients with severe PFP showed lower rates than those with moderate PFP. A lower Sunnybrook score in PFP patients correlated with a smaller rate of blood flow changes in the periocular region. For patients with Bell's palsy, blood flow rate changes in the periocular region at two- and four-months post-surgery were significantly different from pre-surgery levels. There was also a significant difference between the rates at two and four months. In patients with Ramsay Hunt syndrome, the rate of blood flow changes at two months post-surgery did not significantly differ from pre-surgery. No significant difference in blood flow rate changes at two months post-surgery was observed between patients with Bell's palsy and Ramsay Hunt syndrome. Facial blood perfusion decreased with the severity of facial nerve injury in PFP patients, regardless of the etiology. Postoperative improvements were significant in Bell's palsy, but slower in Ramsay Hunt syndrome.