Patrick Grogan

Practice parameter: Steroids, acyclovir, and surgery for Bell’s palsy (an evidence-based review) Report of the Quality Standards Subcommittee of the American Academy of Neurology

Objective: To determine the effectiveness of steroids, acyclovir, and surgical facial nerve decompression in Bell’s palsy. Methods: The authors identified articles by searching MEDLINE and selected those that prospectively compared outcomes in patients treated with steroids, acyclovir, or surgery with patients not receiving these modalities. The authors graded the quality of each study (class I to IV) using a standard classification-of-evidence scheme. They compared the proportion of patients recovering facial function in the treated group to the proportion of patients recovering facial function in the control group. Results: The authors identified no adequately powered class I studies for any treatment modality. The pooled results of two class I and two class II studies showed significantly better facial outcomes in steroid-treated patients compared with non–steroid-treated patients (relative rate good outcome 1.16, 95% CI 1.05 to 1.29). One class II study demonstrated a significant benefit from acyclovir in combination with prednisone compared with prednisone alone (relative rate good outcome 1.22, 95% CI 1.02 to 1.45). All studies describing outcomes in patients treated with facial nerve decompression were graded as class IV. Conclusion: For patients with Bell’s palsy, a benefit from steroids, acyclovir, or facial nerve decompression has not been definitively established. However, available evidence suggests that steroids are probably effective and acyclovir (combined with prednisone) is possibly effective in improving facial functional outcomes. There is insufficient evidence to make recommendations regarding surgical facial nerve decompression for Bell’s palsy. Well-designed studies of the effectiveness of treatments for Bell’s palsy are still needed.

White matter hyperintensities on MRI in high-altitude U-2 pilots

Objective: To demonstrate that U-2 pilot occupational exposure to hypobaria leads to increased incidence of white matter hyperintensities (WMH) with a more uniform distribution throughout the brain irrespective of clinical neurologic decompression sickness history. Methods: We evaluated imaging findings in 102 U-2 pilots and 91 controls matched for age, health, and education levels. Three-dimensional, T2-weighted, high-resolution (1-mm isotropic) imaging data were collected using fluid-attenuated inversion recovery sequence on a 3-tesla MRI scanner. Whole-brain and regional WMH volume and number were compared between groups using a 2-tailed Wilcoxon rank sum test. Results: U-2 pilots demonstrated an increase in volume (394%; p = 0.004) and number (295%; p < 0.001) of WMH. Analysis of regional distribution demonstrated WMH more uniformly distributed throughout the brain in U-2 pilots compared with mainly frontal distribution in controls. Conclusion: Pilots with occupational exposure to hypobaria showed a significant increase in WMH lesion volume and number. Unlike the healthy controls with predominantly WMH in the frontal white matter, WMH in pilots were more uniformly distributed throughout the brain. This is consistent with our hypothesized pattern of damage produced by interaction between microemboli and cerebral tissue, leading to thrombosis, coagulation, inflammation, and/or activation of innate immune response, although further studies will be necessary to clarify the pathologic mechanisms responsible.

White Matter Hyperintensities and Hypobaric Exposure

Demonstrate that occupational exposure to nonhypoxic hypobaria is associated with subcortical white matter hyperintensities (WMHs) on fluid‐attenuated inversion recovery magnetic resonance imaging (MRI).

OnabotulinumtoxinA Successfully Used as Migraine Prophylaxis During Pregnancy: A Case Report

Botulinum toxin (btx) received U.S. Food and Drug Administration approval for migraine treatment in 2010 with a pregnancy category C. There are minimal reports of its usage in pregnancy with no adverse effects; however, there are no reported cases of usage in a known pregnancy for the successful treatment of migraines. We present a patient with a history of 4 to 5 migraines per week refractory to treatment who was subsequently controlled with btx. She initially stopped injections, however, her migraines increased to 5 to 6 per week while using standard medications for migraine treatment in pregnancy. She requested btx while 18 weeks pregnant after which she had full resolution of her migraines. She gave birth to a healthy full-term girl with no neuromuscular or developmental concerns spanning the first 6.5 years of her life, the longest reported follow-up of an infant whose mother received btx while pregnant. This is the first reported case in the literature of a patient requesting btx injections for migraine treatment while knowingly pregnant. The foundation of a btx pregnancy registry, similar to those used for antiepileptics, would be greatly beneficial to gather more safety data in regard to its further usage during pregnancy.

Headache Direction and Aura Predict Migraine Responsiveness to Rimabotulinumtoxin B

To report a retrospective analysis of patients with migraine headaches treated with rimabotulinumtoxin B as preventive treatment, investigating an association between clinical responsiveness with migraine directionality and migrainous aura.

White matter integrity in high-altitude pilots exposed to hypobaria

INTRODUCTION Nonhypoxic hypobaric (low atmospheric pressure) occupational exposure, such as experienced by U.S. Air Force U-2 pilots and safety personnel operating inside altitude chambers, is associated with increased subcortical white matter hyperintensity (WMH) burden. The pathophysiological mechanisms underlying this discrete WMH change remain unknown. The objectives of this study were to demonstrate that occupational exposure to nonhypoxic hypobaria is associated with altered white matter integrity as quantified by fractional anisotropy (FA) measured using diffusion tensor imaging and relate these findings to WMH burden and neurocognitive ability. METHODS There were 102 U-2 pilots and 114 age- and gender-controlled, health-matched controls who underwent magnetic resonance imaging. All pilots performed neurocognitive assessment. Whole-brain and tract-wise average FA values were compared between pilots and controls, followed by comparison within pilots separated into high and low WMH burden groups. Neurocognitive measurements were used to help interpret group difference in FA values. RESULTS Pilots had significantly lower average FA values than controls (0.489/0.500, respectively). Regionally, pilots had higher FA values in the fronto-occipital tract where FA values positively correlated with visual-spatial performance scores (0.603/0.586, respectively). There was a trend for high burden pilots to have lower FA values than low burden pilots. DISCUSSION Nonhypoxic hypobaric exposure is associated with significantly lower average FA in young, healthy U-2 pilots. This suggests that recurrent hypobaric exposure causes diffuse axonal injury in addition to focal white matter changes.McGuire SA, Boone GRE, Sherman PM, Tate DF, Wood JD, Patel B, Eskandar G, Wijtenburg SA, Rowland LM, Clarke GD, Grogan PM, Sladky JH, Kochunov PV. White matter integrity in high-altitude pilots exposed to hypobaria. Aerosp Med Hum Perform. 2016; 87(12):983-988.