The value of ultrasound-guidance of nerves and muscles for patient tolerance and parameters electrodiagnostic studies.

Objective: To assess impact of ultrasound guidance (USG) on patient's perception of nerve conduction studies (NCS). Methods: In this single-center, randomized, sham-controlled, parallel, single-blind trial, we evaluated ultrasound (US) in identifying NCS stimulation site. Consecutive adults (18-80 old) without neuropathy referred for NCS were electronically randomized 1:1 to USG or Sham US. The primary outcome was sensory supramaximal intensity (SSMI) for each site/nerve; motor supramaximal intensity (MSMI), amplitudes, number of non-routine muscle punctured, Visual Analogue Scale (VAS), satisfaction were secondary outcomes. Results: 290 participants were randomized, with 145 in the USG and 144 Sham US groups, respectively. No difference in SSMI, CMAP or SNAP, VAS, satisfaction was recorded. With USG, the median at the elbow and fibular MMSI were lower (p = 0.04; p = 0.02). With normal NCS or overweight and obese subgroups patients had lower median SSMI (p = 0.05/ p = 0.02), higher median and sural SNAP with normal NCS (p = 0.04; p = 0.007) and the sural SNAP for the expert US subgroup (p = 0.02). Conclusions: USG is useful for nerves, that are anatomically variable or in obesity. The sural SNAP gain with US in the normal NCS subgroup could facilitate routine NCS. Significance: In standard NCS the USG does not modify the patient's tolerance.Trial Registration: clinicaltrials.gov (NCT03868189).

Spinal cord lesion mimicking a dysimmune myelitis revealing CANVAS syndrome.

CONTEXT: Posterior spinal cord lesions are found in patients with ganglionopathy. These are normally found in later stages of the neuronopathy as a consequence of dorsal root ganglia degeneration. Cerebellar Ataxia, Neuropathy, Vestibular Areflexia Syndrome (CANVAS) is an emerging neurological disorder. Myelitis lesions have been described in confirmed CANVAS cases. FINDINGS: We describe a case of a 68-year-old woman with slowly progressive ataxia with paresthesia. Laboratory tests were normal. Total spine MRI showed a C4 posterior spinal cord lesion. Lumbar puncture was positive for oligoclonal bands with normal IgG index and protein level. Paraneoplastic antibodies were not detected. Electromyography showed nonlength dependent sensory neuropathy. The patient was treated with intravenous immunoglobulin for suspected dysimmune myelitis. Over 6 years, she progressively developed other neurological manifestations evoking CANVAS. Nerve conduction study showed isolated sensory impairment over the years and peripheral nerve ultrasound revealed abnormally small nerves. Further genetic testing confirmed the diagnosis. CONCLUSION: This is the first case of CANVAS syndrome presenting initially with an isolated spinal cord lesion mimicking dysimmune myelitis. The purpose of this case report is to add to the current literature about this evolving neurological syndrome and to aid clinicians in their diagnostic approach in clinical practice.

Performance of the Wells score in predicting deep vein thrombosis in medical and surgical hospitalized patients with or without thromboprophylaxis: The R-WITT study.

The Wells score had shown weak performance to determine pre-test probability of deep vein thrombosis (DVT) for inpatients. So, we evaluated the impact of thromboprophylaxis on the utility of the Wells score for risk stratification of inpatients with suspected DVT. This bicentric cross-sectional study from February 1, 2018 to January 31, 2019 included consecutive medical and surgical inpatients who underwent lower limb ultrasound study for suspected DVT. Wells score clinical predictors were assessed by both ordering and vascular physicians within 24 h after clinical suspicion of DVT. Primary outcome was the Wells score's accuracy for pre-test risk stratification of suspected DVT, accounting for anticoagulation (AC) treatment (thromboprophylaxis for ⩾ 72 hours or long-term anticoagulation). We compared prevalence of proximal DVT among the low, moderate and high pre-test probability groups. The discrimination accuracy was defined as area under the receiver operating characteristics (ROC) curve. Of the 415 included patients, 30 (7.2%) had proximal DVT. Prevalence of proximal DVT was lower than expected in all pre-test probability groups. The prevalence in low, moderate and high pre-test probability groups was 0.0%, 3.1% and 8.2% (p = 0.22) and 1.7%, 4.2% and 25.8% (p < 0.001) for inpatients with or without AC, respectively. Area under ROC curves for discriminatory accuracy of the Wells score, for risk of proximal DVT with or without AC, was 0.72 and 0.88, respectively. The Wells score performed poorly for discrimination of risk for proximal DVT in hospitalized patients with AC but performed reasonably well among patients without AC; and showed low inter-rater reliability between physicians. ClinicalTrials.gov Identifier: NCT03784937.

Systolic peak foot-to-apex time interval, a novel oscillometric technique for systolic blood pressure measurement.

BACKGROUND: Noninvasive blood pressure (BP) measurement is essential for the study of human physiology but automatic oscillometric devices only estimate SBP and DBP using various, undisclosed algorithms, precluding standardization and interchangeability. We propose a novel approach by tracking, during pneumatic cuff deflation, the time interval from the foot to the apex of the systolic peak of the oscillometric signal, which reaches a maximum concomitant with the first Korotkoff sound. METHOD: In 145 study participants and patients (group 1), we measured the systolic brachial artery blood pressure by Korotkoff sound recording, conventional oscillometry, and our fully automated systolic peak foot-to-apex time interval (SFATI) technique. In 35 other patients (group 2), we compared SFATI with intra-arterial measurement. RESULTS: In group 1, the concordance correlation coefficient was 0.989 and 0.984 between SFATI and Korotkoff sounds, 0.884 and 0.917 between oscillometry and Korotkoff sounds, and 0.882 and 0.919 between SFATI and oscillometry, respectively, on the left and right arm. In group 2, it was 0.72 between SFATI and intra-arterial measurement, 0.67 between oscillometry and intra-arterial measurement, and 0.92 between SFATI and Korotkoff sounds. In 40 study participants, the reproducibility study yielded a concordance coefficient of 0.95 for SFATI and 0.94 for Korotkoff sounds. CONCLUSION: SFATI BP measurement shows an excellent concordance with the auscultatory technique, offering a major improvement over current oscillometric techniques and allowing standardization.

An ultrasound look at Korotkoff sounds: the role of pulse wave velocity and flow turbulence.

AIMS: The aim of this study was to analyze the temporal relationships between pressure, flow, and Korotkoff sounds, providing clues for their comprehensive interpretation. MATERIALS AND METHODS: When measuring blood pressure in a group of 23 volunteers, we used duplex Doppler ultrasonography to assess, under the arm-cuff, the brachial artery flow, diameter changes, and local pulse wave velocity (PWV), while recording Korotkoff sounds 10 cm downstream together with cuff pressure and ECG. RESULTS: The systolic (SBP) and diastolic (DBP) blood pressures were 118.8±17.7 and 65.4±10.4 mmHg, respectively (n=23). The brachial artery lumen started opening when cuff pressure decreased below the SBP and opened for an increasing length of time until cuff pressure reached the DBP, and then remained open but pulsatile. A high-energy low-frequency Doppler signal, starting a few milliseconds before flow, appeared and disappeared together with Korotkoff sounds at the SBP and DBP, respectively. Its median duration was 42.7 versus 41.1 ms for Korotkoff sounds (P=0.54; n=17). There was a 2.20±1.54 ms/mmHg decrement in the time delay between the ECG R-wave and the Korotkoff sounds during cuff deflation (n=18). The PWV was 10±4.48 m/s at null cuff pressure and showed a 0.62% decrement per mmHg when cuff pressure increased (n=13). CONCLUSION: Korotkoff sounds are associated with a high-energy low-frequency Doppler signal of identical duration, typically resulting from wall vibrations, followed by flow turbulence. Local arterial PWV decreases when cuff pressure increases. Exploiting these changes may help improve SBP assessment, which remains a challenge for oscillometric techniques.

Relevance of corpus callosum splenium versus middle cerebellar peduncle hyperintensity for FXTAS diagnosis in clinical practice.

Fragile X-associated tremor ataxia syndrome (FXTAS) is caused by FMR1 premutation. The features include ataxia, action tremor and middle cerebellar peduncle (MCP) hyperintensity, the latter being the only major radiological criterion in the diagnosis of definite FXTAS until very recently. The importance of corpus callosum splenium (CCS) hyperintensity was recently reported and this sign is now considered as an additional major radiological diagnostic criterion in the diagnosis of FXTAS. However, little is known about its relevance for the diagnosis of FXTAS in clinical practice. We report a practical justification of the relevance of CCS hyperintensity in parallel with MCP hyperintensity for the diagnosis of FXTAS. Clinical and radiological study of 22 FMR1 premutation carriers with neurological signs that may be encountered in FXTAS compared to series of patients with essential tremor, multiple system atrophy of cerebellar type, Parkinson's disease, Alzheimer's disease and stroke. Among the 22 patients with FMR1 premutation [17 men, 5 women; mean age, 63 ± 7.5 (46-84)], 14 were diagnosed with definite FXTAS with the initial criteria. Considering CCS hyperintensity as a new major radiological criterion permitted the diagnosis of definite FXTAS in 3 additional patients. Overall CCS proved as frequent as MCP hyperintensity (64 versus 64 %), while 23 % of patients had CCS but not MCP hyperintensity, 14 % of patients had CCS hyperintensity but neither MCP, nor brainstem hyperintensity. In contrast with CCS hyperintensity, MCP hyperintensity proved less frequent in women than in men. CCS and MCP hyperintensity were more frequent in FXTAS than in the other neurodegenerative disorders. The combination of CCS and MCP hyperintensity was specific of FXTAS. We confirmed the relevance of CCS hyperintensity in FXTAS and we clarified its interest compared to MCP hyperintensity. Our results support the inclusion of CCS hyperintensity in the diagnostic criteria as a new major radiological criterion.