Risk factors for nonidiopathic and idiopathic facial nerve palsies: findings of a retrospective study.

BACKGROUND: Idiopathic (IF) and nonidiopathic facial (NIF) nerve palsies are the most common forms of peripheral facial nerve palsies. Various risk factors for IF palsies, such as weather, have been explored, but such associations are sparse for NIF palsies, and it remains unclear whether certain diagnostic procedures, such as contrast agent-enhanced cerebral magnetic resonance imaging (cMRI), are helpful in the differential diagnosis of NIF vs. IF. METHODS: In this retrospective, monocentric study over a five-year period, the medical reports of 343 patients with peripheral facial nerve palsy were analysed based on aetiology, sociodemographic factors, cardiovascular risk factors, consultation time, diagnostic procedures such as cMRI, and laboratory results. We also investigated whether weather conditions and German Google Trends data were associated with the occurrence of NIF. To assess the importance of doctors' clinical opinions, the documented anamneses and clinical examination reports were presented and rated in a blinded fashion by five neurology residents to assess the likelihood of NIF. RESULTS: A total of 254 patients (74%) had IF, and 89 patients (26%) had NIF. The most common aetiology among the NIF patients was the varicella zoster virus (VZV, 45%). Among the factors analysed, efflorescence (odds ratio (OR) 17.3) and rater agreement (OR 5.3) had the highest associations with NIF. The day of consultation (Friday, OR 3.6) and the cMRI findings of contrast enhancement of the facial nerve (OR 2.3) were also risk factors associated with NIF. In contrast, the local weather, Google Trends data, and cardiovascular risk factors were not associated with NIF. CONCLUSION: The findings of this retrospective study highlight the importance of patient history and careful inspections to identify skin lesions for the differential diagnosis of acute facial nerve palsy. Special caution is advised for hospital physicians during the tick season, as a surge in NIF cases can lead to a concomitant increase in IF cases, making it challenging to choose adequate diagnostic methods.

Antiganglioside antibody frequency in routine clinical care settings.

BACKGROUND AND PURPOSE: Antiganglioside antibodies (AGAs) might be involved in the etiopathogenesis of many neurological diseases, such as Miller-Fisher syndrome (MFS) and Guillain-Barré syndrome (GBS). Available comprehensive reference data regarding AGA positivity rates and cross-responsiveness among AGAs (where one line immunoblot is positive for ≥1 AGA) during routine clinical care are scant. METHODS: In this 10-year monocentric retrospective study, 3560 immunoglobulin (Ig) G and IgM line blots (GA Generic Assays' Anti-Ganglioside Dot kit) obtained using cerebrospinal fluid (CSF) and serum samples from 1342 patients were analyzed for AGA positivity in terms of 14 diagnosis categories and AGA cross-responsiveness. RESULTS: Of all 3560 line blots 158 (4.4%) and of all CSF samples 0.4% (4/924) CSF line blots were AGA positive. For serum IgG, blots with positivity rates higher than the standard deviation of 15.6% were associated with MFS (GD3, GD1a, GT1a and GQ1b) and acute motor axonal neuropathy (AMAN) (GM1, GD1a and GT1a). For serum IgM, blots with positivity rates higher than the standard deviation of 8.1% were associated with AMAN (GM2, GT1a and GQ1b), MFS (GM1, GT1a and GQ1b), multifocal motor neuropathy (MMN) (GM1, GM2 and GQ1b) and chronic inflammatory demyelinating polyneuropathy (CIDP) (GM1). Cross-responsiveness was observed in 39.6% of all positive serum AGA. CONCLUSIONS: Testing for AGAs during routine clinical care rarely led to positive findings, both in serum and even less in CSF, except for the diagnoses AMAN, MFS, MMN and CIDP. Nonspecific findings found as cross-responsiveness between different AGA samples occur frequently, impacting the positivity of most AGA subtypes.

Patterns of subregional cerebellar atrophy across epilepsy syndromes: An ENIGMA-Epilepsy study.

OBJECTIVE: The intricate neuroanatomical structure of the cerebellum is of longstanding interest in epilepsy, but has been poorly characterized within the current corticocentric models of this disease. We quantified cross-sectional regional cerebellar lobule volumes using structural magnetic resonance imaging in 1602 adults with epilepsy and 1022 healthy controls across 22 sites from the global ENIGMA-Epilepsy working group. METHODS: A state-of-the-art deep learning-based approach was employed that parcellates the cerebellum into 28 neuroanatomical subregions. Linear mixed models compared total and regional cerebellar volume in (1) all epilepsies, (2) temporal lobe epilepsy with hippocampal sclerosis (TLE-HS), (3) nonlesional temporal lobe epilepsy, (4) genetic generalized epilepsy, and (5) extratemporal focal epilepsy (ETLE). Relationships were examined for cerebellar volume versus age at seizure onset, duration of epilepsy, phenytoin treatment, and cerebral cortical thickness. RESULTS: Across all epilepsies, reduced total cerebellar volume was observed (d = .42). Maximum volume loss was observed in the corpus medullare (dmax = .49) and posterior lobe gray matter regions, including bilateral lobules VIIB (dmax = .47), crus I/II (dmax = .39), VIIIA (dmax = .45), and VIIIB (dmax = .40). Earlier age at seizure onset ( η ρ max 2 = .05) and longer epilepsy duration ( η ρ max 2 = .06) correlated with reduced volume in these regions. Findings were most pronounced in TLE-HS and ETLE, with distinct neuroanatomical profiles observed in the posterior lobe. Phenytoin treatment was associated with reduced posterior lobe volume. Cerebellum volume correlated with cerebral cortical thinning more strongly in the epilepsy cohort than in controls. SIGNIFICANCE: We provide robust evidence of deep cerebellar and posterior lobe subregional gray matter volume loss in patients with chronic epilepsy. Volume loss was maximal for posterior subregions implicated in nonmotor functions, relative to motor regions of both the anterior and posterior lobe. Associations between cerebral and cerebellar changes, and variability of neuroanatomical profiles across epilepsy syndromes argue for more precise incorporation of cerebellar subregional damage into neurobiological models of epilepsy.