Association Study of Apolipoprotein E Gene Polymorphism With Incidence and Delayed Resolution of Hemifacial Spasm

Objective: This study investigates the correlation between Apolipoprotein E gene (APOE) polymorphism and the incidence and delayed resolution of hemifacial spasms.Methods: The APOE genotypes of 151 patients with hemifacial spasm and 73 control cases were determined by cleaved amplification polymorphism sequence-tagged sites. The distribution of three APOE alleles (ε2, ε3, and ε4) in two groups and the delayed resolution rate in 6 genotypes were calculated and statistically analyzed.Results: The proportion of patients with APOE ε3/ε4 genotype in the hemifacial spasm group (25.17%) was significantly higher than that in the control group (12.33%) (P = 0.027). In terms of allele frequency, the proportion of the APOE ε4 allele in the hemifacial spasm group (15.56%) was significantly higher than that in the control group (6.85%) (P = 0.009). Meanwhile, the proportion of APOE ε4 allele carriers in the hemifacial spasm group (29.80%) was significantly higher than that in the control group (13.7%) (P = 0.009). Logistic regression analysis showed that the ε4 allele significantly increased the incidence of hemifacial spasm (OR 2.675, 95%CI 1.260-5.678, P = 0.010). Among the 32 patients with a delayed resolution, the ε3/ε3 and ε3/ε4 had the highest proportion in 6 genotypes. The delayed resolution rate of APOE ε3/ε4 (34.21%) was significantly higher than APOE ε3/ε3 (17.78%) (P < 0.05). The delayed resolution rate of APOE ε4 carriers was the highest (33.33%) in the 3 allele carriers, but there was no significant difference among the 3 allele carriers (P = 0.065).Conclusion: The polymorphism of APOE is relevant to the incidence rate of hemifacial spasms. APOE ε4 allele increases the incidence of hemifacial spasm. The APOE ε4 allele may promote the occurrence of delayed resolution.

Facial twitching: calcium or concussion conundrum? Hypocalcaemia in a young American football player masking an internal carotid artery dissection

A 30-year-old male American football player presented to the acute medical unit with left-hand and hemifacial spasms. History and examination revealed hemifacial spasms in keeping with seizure-like activity possibly due to symptomatic hypocalcaemia. Subsequent investigations revealed an adjusted calcium of 1.87 mmol/L and, hence, he was managed with intravenous calcium replacement. He presented two further times in a 1-month period, with subjective limb weakness, despite normal adjusted calcium. During his third admission, he developed slurred speech and a marked facial droop, with absence of power in the right upper limb. Imaging revealed acute and old infarctions in the left middle cerebral artery territory and appearances consistent with left internal carotid artery dissection. This presentation of arterial stroke is atypical but with potentially grave consequences if missed. There is limited literature on the presentation of hemifacial spasm, and its association with ischaemic or haemorrhagic stroke represents a key learning point.

Computational Fluid Dynamics as an Indicator of Offending Vessel in Trigeminal Neuralgia and Hemifacial Spasms

Context: Newer Imaging tool for diagnosing offending vessel in trigeminal neuralgia (TN) and Hemifacial spasms (HFS). Aim: To find out if Computational FluidDynamics (CFD) can correctly predict the offending vessel in HFS and TN & thus improving the outcome of Microvascular Decompression) MVD. Settings and Design: CFD is a relatively new mode of imaging. Its application to indicate offending vessel in TN & HFS was tested. Materials & Methods: Retrospectively we studied 13 consecutive patients operated in 2017 for either HFS or TN. Preoperatively MRI & Computed Tomography Angiogram (CTA) were done and the offending vessel identified along with its point of contact with the concerned nerve. CFD was done using Hemoscope 2015 software and wall pressure, wall shear stress, vector & streamline flow were obtained in the offending vessel (test) & contralateral vessel (control). Results of these were charted on an excel sheet & results analyzed. The postoperativeoutcome were assessed and compared with CFD results. Statistical analysis used: Small study group hence statistical analysis couldn’t be applied. Results: Of the 13 patients, offending artery had high wall pressure in 12 and increased wall shear stress innine. Among the controls six had high wall pressure and only two had high wall shear stress. Conclusion: CFD can be used to determine offending vessel and can predict good outcome following microvascular decompression.