Neurology

Correction to: Telemedicine in general neurology: use of audiovisual consultation for on call back-up service in an acute care hospital The original version of this article unfortunately contained a mistake in the acknowledgement section.

How often are patients with progressive supranuclear palsy really falling?

Insufficient image quality

Video head impulse test contributes to Susac syndrome diagnosis

Neurotoxicity of novel cancer immunotherapies

Jean Jacques Lhermitte (1877–1959)

Idiopathic acute high-tone sensorineural hearing loss accompanied by vertigo: vestibulo-cochlear artery syndrome? Consideration based on VEMP and vHIT

The misdiagnosis of functional disorders as other neurological conditions Abstract Background Several studies have shown that when patients with functional neurological disorders are followed up, it is rare to find another neurological condition that better explains the initial symptoms in hindsight. No study has examined the reverse, studying patients with a range of neurological disease diagnoses with the aim of assessing how often a new diagnosis of functional disorder better explains the original symptoms. Methods A prospective multi-centre cohort study of 2637 new neurology outpatient referrals from primary care in Scotland. Neurologists provided initial diagnoses and a rating of the extent to which their symptoms were explained by an ‘organic’ neurological disease. Patients were followed up 19 months later with a questionnaire to their primary care physician asking about diagnostic change, and when indicated also by discussion with the original assessing neurologist and review of secondary care records. Results Valid responses were obtained for 2378 out of 2637 patients (90%) with symptoms ‘largely’ or ‘completely’ explained by organic disease at baseline. At follow-up, we found diagnostic errors in 48 patients. Of those, ten (0.4%) had a functional diagnosis and 38 patients (1.6%) had a different ‘organic’ diagnosis which better explained the original symptoms. Conclusions Patients diagnosed with neurological disease sometimes have a functional diagnosis at follow-up which, with hindsight, better explains the original symptoms. This occurs at a frequency similar to the misdiagnosis of ‘organic’ neurological disease as functional disorder. Misdiagnosis can harm patients in either direction, especially as we enter an era of evidence-based treatment for functional neurological disorders.

Misjudgment of pre-stroke functional status contradicts beneficial outcomes after endovascular therapy for large vessel occlusion Abstract Endovascular therapy (EVT) trials enrolled ischemic stroke patients with good pre-stroke functional status. However, this information needed for rapid decision-making is commonly lacking in clinical practice. We hypothesized that initial misjudgment of pre-stroke functional status attenuates clinical outcomes of EVT. Data were derived from our prospective registry of ischemic stroke patients undergoing EVT for anterior circulation large vessel occlusion (01/2016–12/2017). Considering all information accumulated during hospital course, pre-stroke modified Rankin scale (mRS) was independently re-assessed and compared with pre-EVT assessments. Misjudgment was defined as any difference in mRS categories between first- and second-look assessments. Multivariable model was built to adjust for confounding variables of unfavorable outcome (mRS 3–6) and death at 90 days. Overall, we studied 217 patients: median age 75 years (IQR 64–81), 54% women, median NIHSS 17 (12–20) points. Second-look assessment of pre-stroke mRS revealed 73 (34%) cases initially being misjudged by ≥ 1 category and 17 (8%) by ≥ 2 categories. None of the second-look mRS assessments resulted in a lower mRS category than initially rated. Patients whose pre-stroke mRS score was misjudged prior to EVT showed more frequently unfavorable outcome (62/73 [84.9%] vs. 94/144 [65.3%], p = 0.002) or were deceased (30/73 [41.1%] vs. 25/144 [17.4%], p < 0.001) at 90 days than patients with consistent mRS assessments. Moreover, unfavorable outcomes occurred in nearly all patients whose initial mRS was misjudged by ≥ 2 categories (mRS 3–6: 17/17 [100%]; death: 14/17 [82.4%]; p < 0.001). In conclusion, thorough pre-EVT assessment of pre-stroke functional status appears decisive for proper selection of EVT candidates.

An update on genetic frontotemporal dementia Abstract Frontotemporal dementia (FTD) is a highly heritable group of neurodegenerative disorders, with around 30% of patients having a strong family history. The majority of that heritability is accounted for by autosomal dominant mutations in the chromosome 9 open reading frame 72 (C9orf72), progranulin (GRN), and microtubule-associated protein tau (MAPT) genes, with mutations more rarely seen in a number of other genes. This review will discuss the recent updates in the field of genetic FTD. Age at symptom onset in genetic FTD is variable with recently identified genetic modifiers including TMEM106B (in GRN carriers particularly) and a polymorphism at a locus containing two overlapping genes LOC101929163 and C6orf10 (in C9orf72 carriers). Behavioural variant FTD (bvFTD) is the most common diagnosis in each of the genetic groups, although in C9orf72 carriers amyotrophic lateral sclerosis either alone, or with bvFTD, is also common. An atypical neuropsychiatric presentation is also seen in C9orf72 carriers and family members of carriers are at greater risk of psychiatric disorders including schizophrenia and autistic spectrum disorders. Large natural history studies of presymptomatic genetic FTD are now underway both in Europe/Canada (GENFI—the Genetic FTD Initiative) and in the US (ARTFL/LEFFTDS study), collaborating together under the banner of the FTD Prevention Initiative (FPI). These studies are taking forward the validation of cognitive, imaging and fluid biomarkers that aim to robustly measure disease onset, staging and progression in genetic FTD. Grey matter changes on MRI and hypometabolism on FDG-PET are seen at least 10 years before symptom onset with white matter abnormalities seen earlier, but the pattern and exact timing of changes differ between different genetic groups. In contrast, tau PET has yet to show promise in genetic FTD. Three key fluid biomarkers have been identified so far that are likely to be helpful in clinical trials—CSF or blood neurofilament light chain levels (in all groups), CSF or blood progranulin levels (in GRN carriers) and CSF poly(GP) dipeptide repeat protein levels (in C9orf72 carriers). Increased knowledge about genetic FTD has led to more clinical presymptomatic genetic testing but this has not yet been mirrored in the development of either an accepted FTD-specific testing protocol or provision of appropriate psychological support mechanisms for those living through the at-risk phase. This will become even more relevant as disease-modifying therapy trials start in each of the genetic groups over the next few years.