High-resolution ultrasound demonstrates in vivo effects of wrist movement on the median nerve along the forearm.

INTRODUCTION/AIMS: High-resolution ultrasound (HRUS) is the imaging method of choice to visualize peripheral nerve size, structure, and biomechanical performance. The purpose of this study was to show and quantify the effects of active and passive wrist alignment on median nerve (MN) cross-sectional area (CSA) along the forearm in a healthy population. METHODS: Sixteen healthy volunteers underwent HRUS of their dominant forearm (n = 16, 10 males, 6 females, 18-55 y of age). Median nerve's CSA was assessed at four defined areas on the forearm in relation to active and passive wrist alignment. RESULTS: Changes in wrist alignment were significantly associated with MN CSA (P < .001), regardless if the wrist was moved actively or passively. MN CSA was lowest during passive extension of the wrist joint and highest during passive flexion of the wrist joint (range: 4.5-23.2 mm2 ). DISCUSSION: The elasticity of nerve tissue, the loose connective tissue between the fascicles, and the paraneurium allow peripheral nerves to adapt to longitudinal strain. HRUS enables the demonstration of significant median nerve CSA changes along the forearm during active and passive wrist movement in healthy volunteers.

Cutaneous nerve fields of the anteromedial lower limb-Determination with selective ultrasound-guided nerve blockade.

BACKGROUND: This study aimed to determine the peripheral cutaneous nerve fields (CNF), their variability, and potential overlap by selectively blocking the intermediate (IFCN) and medial (MFCN) femoral cutaneous nerves and the infrapatellar branch of the saphenous nerve (IPBSN) in healthy volunteers. METHODS: In this prospective study, ultrasound-guided nerve blockades of the IFCN, MFCN, and IPBSN in 14 healthy volunteers were administered. High-frequency probes (15-22 MHz) and 1 ml of 1% lidocaine per nerve were used. The area of sensory loss was determined using a pinprick, and all fields were drawn on volunteers' skin. A three-dimensional (3D) scan of all lower limbs was obtained and the three CNF and their potential overlap were measured. RESULTS: The mean size of innervation areas showed a high variability of peripheral CNF, with 258.58 ± 148.26 mm2 (95% CI, 169-348.18 mm2 ) for the IFCN, 193.26 ± 72.08 mm2 (95% CI, 124.45-262.08 mm2 ) for the MFCN, and 166.78 ± 121.30 mm2 (95% CI, 94.1-239.46 mm2 ) for the IPBSN. In 11 volunteers, we could evaluate an overlap between the IFCN and MFCN (range, 4.11-139.68 ± 42.70 mm2 ), and, in 10 volunteers, between the MFCN and IPBSN (range, 11.12-224.95 ± 79.61 mm2 ). In only three volunteers was an overlap area found between the IFCN and IPBSN (range, 7.46-224.95 ± 88.88 mm2 ). The 3D-scans confirmed the high variability of the peripheral CNF. CONCLUSIONS: Our study successfully determined CNF, their variability, and the overlap of the MFCN, IFCN, and IPBSN in healthy volunteers. Therefore, we encourage physicians to use selective nerve blockades to correctly determine peripheral CNF at the anteromedial lower limb.

Temporal trends in intracerebral hemorrhage: Evidence from the Austrian Stroke Unit Registry.

BACKGROUND: To assess changes in frequency, severity, complications, therapy and outcome of intracerebral hemorrhage in patients treated in stroke units in Austria, we evaluated data from the Austrian Stroke Unit Registry between 2008 and 2016. METHODS AND FINDINGS: Data of 6707 cases of ICH covering a time span of 9 years and including information on age, risk factors, pre-stroke modified Rankin Score (mRS), baseline stroke severity (NIHSS), complications, therapy, functional outcome, and mortality were extracted from the Austrian Stroke Unit Registry. A multivariate regularized logistic regression model and linear models for temporal dependence were computed for analyzing statistical inference and time trends. Bonferroni correction was applied to correct for multiple testing. Between 2008 and 2016, the proportion of ICH admissions to stroke units in Austria declined, with a shift among patients towards older age (>70 years, p = 0.04) and lower admission NIHSS scores. While no significant time trends in risk factors, pre-stroke mRS and medical complications were observed, therapeutic interventions declined significantly (p<0.001). Three-month mortality increased over the years independently (p = 0.003). CONCLUSIONS: Despite declining incidence and clinical severity of ICH we observed a clear increase in three-month mortality. This effect seems to be independent of predictors including age, admission NIHSS, pre-morbid MRS, or medical complications. The observations from this large retrospective database cohort study underline an urgent call for action in the therapy of ICH.

Effects of SSRI exposure on hemorrhagic complications and outcome following thrombolysis in ischemic stroke.

Background Selective serotonin reuptake inhibitors (SSRI) may interfere with platelet function, and pre-stroke SSRI treatment has been associated with increased hematoma volumes and mortality in hemorrhagic stroke patients. The effects of SSRI on the risk of hemorrhagic complications after thrombolysis in ischemic stroke patients are unclear. Aims To examine the effects of pre-stroke SSRI exposure on bleeding complications, functional outcome, and mortality following thrombolysis in ischemic stroke. Methods Data including standard demographic and clinical variables as well as baseline and follow-up stroke severity (measured by National Institutes of Health Stroke Score), functional outcome (measured by modified Rankin Scale) at 3 months, and mortality at 7 and 90 days were extracted from the Virtual International Stroke Trials Archive. Multivariable binary logistic regression was used for statistical analyses. Results Out of 1114 ischemic stroke patients treated with recombinant tissue-type plasminogen activator, 135 (12.1%) had previous SSRI exposure. Symptomatic intracranial hemorrhage occurred in 30 (2.7%) patients. Of those, 2 (1.5%, n = 135) were in the SSRI pretreatment group and 28 (2.9%, n = 979) were SSRI naive patients. Pre-stroke SSRI exposure in thrombolysed patients showed association with neither bleeding complications ( P = .58) nor functional outcome ( P = .38) nor mortality ( P = .65). Conclusions Results from this large retrospective ad hoc database cohort study indicate that pre-stroke SSRI exposure in ischemic stroke patients who receive thrombolytic treatment is not associated with bleeding complications, functional outcome, or mortality.

Fetal MRI detects early alterations of brain development in Tetralogy of Fallot.

OBJECTIVE: Prenatal imaging has identified alterations of brain growth in fetuses with congenital heart disease. However, little is known about the timing of altered brain development and its occurrence in specific congenital heart disease subgroups. This magnetic resonance imaging study aimed to identify early (median, 25 gestational weeks [GW]) changes in fetal total brain (TBV), gray matter (GMV), and subcortical brain (SBV) volumes in Tetralogy of Fallot (TOF) cases in utero. STUDY DESIGN: Fetal magnetic resonance imaging (1.5 Tesla) was performed in 24 fetuses who were diagnosed with TOF and 24 normal age-matched control fetuses (20-34 GW). TBV, GMV, SBV, intracranial cavity, cerebellar, ventricular, and external cerebrospinal fluid volumes were quantified by manual segmentation based on coronal T2-weighted sequences. Mixed model analyses of variance and t-tests were conducted to compare cases and control fetuses. RESULTS: TBV was significantly lower (P < .001) in early (<25 GW) and late TOF cases. Both GMV (P = .003) and SBV (P = .001) were affected. The GMV-to-SBV ratio declined in fetuses with TOF (P = .026). Compared with normal fetuses, ventricular volume was increased (P = .0048). External cerebrospinal fluid was enlarged in relation to head size (P < .001). Intracranial cavity volume (P = .314) and cerebellar volume (P = .074) were not significantly reduced in fetuses with TOF. CONCLUSION: TOF is associated with smaller volumes of gray and white matter and enlarged cerebrospinal fluid spaces. These changes are present at ≤25 GW and indicate altered fetal brain growth in this pathophysiologic entity during early stages of human brain development.