Vestibulo-ocular reflex assessed with Video Head Impulse Test in children with Vestibular Migraine: Our experience.

Vestibular Migraine in children can mimic other disorders, especially at presentation. Outcome is hard to predict and management may be challenging due to the fact that many of the patients are too young to describe their symptoms and these are not always accompanied by headache. OBJECTIVE: To assess vestibulo-ocular reflex (VOR) in pediatric patients who meet criteria for defined Vestibular Migraine and to compare results to healthy controls. METHODS: Twenty-one patients aged 11-16 years were included in this prospective multicentric study. VOR was assessed using the video Head Impulse Test by EyeSeeCam®(Interacoustics, Denmark). RESULTS: Patients with Vestibular Migraine (VM) have higher values of gain compared to asymptomatic patients. CONCLUSION: Video Head Impulse Test (vHIT) is a useful and relatively fast-to-perform examination in children compared to other vestibular tests. Patients with VM seem to have higher values of gain at vHIT.

An innovative strategy for the molecular diagnosis of Usher syndrome identifies causal biallelic mutations in 93% of European patients.

Usher syndrome (USH), the most prevalent cause of hereditary deafness-blindness, is an autosomal recessive and genetically heterogeneous disorder. Three clinical subtypes (USH1-3) are distinguishable based on the severity of the sensorineural hearing impairment, the presence or absence of vestibular dysfunction, and the age of onset of the retinitis pigmentosa. A total of 10 causal genes, 6 for USH1, 3 for USH2, and 1 for USH3, and an USH2 modifier gene, have been identified. A robust molecular diagnosis is required not only to improve genetic counseling, but also to advance gene therapy in USH patients. Here, we present an improved diagnostic strategy that is both cost- and time-effective. It relies on the sequential use of three different techniques to analyze selected genomic regions: targeted exome sequencing, comparative genome hybridization, and quantitative exon amplification. We screened a large cohort of 427 patients (139 USH1, 282 USH2, and six of undefined clinical subtype) from various European medical centers for mutations in all USH genes and the modifier gene. We identified a total of 421 different sequence variants predicted to be pathogenic, about half of which had not been previously reported. Remarkably, we detected large genomic rearrangements, most of which were novel and unique, in 9% of the patients. Thus, our strategy led to the identification of biallelic and monoallelic mutations in 92.7% and 5.8% of the USH patients, respectively. With an overall 98.5% mutation characterization rate, the diagnosis efficiency was substantially improved compared with previously reported methods.