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Background: The Glasgow Coma Scale (GCS) is an essential coma scale in critical care for determining the neurological status of patients and for estimating their long-term prognosis. Similarly, cerebral autoregulation (CA) monitoring has shown to be an accurate technique for predicting clinical outcomes. However, little is known about the relationship between CA measurements and GCS scores among neurological critically ill patients. This study aimed to explore the association between noninvasive CA multimodal monitoring measurements and GCS scores., Methods: Acutely comatose patients with a variety of neurological injuries admitted to a neurocritical care unit were monitored using near-infrared spectroscopy-based multimodal monitoring for up to 72 hours. Regional cerebral oxygen saturation (rScO2), cerebral oximetry index (COx), GCS, and GCS motor data were measured hourly. COx was calculated as a Pearson correlation coefficient between low-frequency changes in rScO2 and mean arterial pressure. Mixed random effects models with random intercept was used to determine the relationship between hourly near-infrared spectroscopy-based measurements and GCS or GCS motor scores., Results: A total of 871 observations (h) were analyzed from 57 patients with a variety of neurological conditions. Mean age was 58.7±14.2 years and the male to female ratio was 1:1.3. After adjusting for hemoglobin and partial pressure of carbon dioxide in arterial blood, COx was inversely associated with GCS (β=-1.12, 95% confidence interval [CI], -1.94 to -0.31, P=0.007) and GCS motor score (β=-1.06, 95% CI, -2.10 to -0.04, P=0.04). In contrast rScO2 was not associated with GCS (β=-0.002, 95% CI, -0.01 to 0.01, P=0.76) or GCS motor score (β=-0.001, 95% CI, -0.01 to 0.01, P=0.84)., Conclusions: This study showed that fluctuations in GCS scores are inversely associated with fluctuations in COx; as COx increases (impaired autoregulation), more severe neurological impairment is observed. However, the difference in COx between high and low GCS is small and warrants further studies investigating this association. CA multimodal monitoring with COx may have the potential to be used as a surrogate of neurological status when the neurological examination is not reliable (ie, sedation and paralytic drug administration).

Freezing of gait is a disabling symptom of Parkinson's disease that causes a paroxysmal inability to generate effective stepping. The underlying pathophysiology has recently migrated towards a dysfunctional supraspinal locomotor network, but the actual network derangements during ongoing gait freezing are unknown. We investigated the communication between the cortex and the subthalamic nucleus, two main nodes of the locomotor network, in seven freely-moving subjects with Parkinson's disease with a novel deep brain stimulation device, which allows on-demand recording of subthalamic neural activity from the chronically-implanted electrodes months after the surgical procedure. Multisite neurophysiological recordings during (effective) walking and ongoing gait freezing were combined with kinematic measurements and individual molecular brain imaging studies. Patients walked in a supervised environment closely resembling everyday life challenges. We found that during (effective) walking, the cortex and subthalamic nucleus were synchronized in a low frequency band (4-13 Hz). In contrast, gait freezing was characterized in every patient by low frequency cortical-subthalamic decoupling in the hemisphere with less striatal dopaminergic innervation. Of relevance, this decoupling was already evident at the transition from normal (effective) walking into gait freezing, was maintained during the freezing episode, and resolved with recovery of the effective walking pattern. This is the first evidence for a decoding of the networked processing of locomotion in Parkinson's disease and suggests that freezing of gait is a 'circuitopathy' related to a dysfunctional cortical-subcortical communication. A successful therapeutic approach for gait freezing in Parkinson's disease should aim at directly targeting derangements of neural network dynamics., (© The Author(s) (2019). Published by Oxford University Press on behalf of the Guarantors of Brain.)

Background: Power and work at the ankle joint during gait are usually computed considering the foot as a rigid body [1-6] (Ankle Joint method, AJ). The foot is instead a deformable structure and can absorb and produce work by pronation/supination, foot arch deformation and other intrinsic movements. A different approach, named "the Distal Shank method (DS)" [7-12] considers all these aspects without increasing the complexity of the protocol, and thus it seems promising for clinical applications [12]., Research Questions: a) To characterize the differences in power and work computed using the two mentioned methods for a relatively large number of subjects walking at different velocities, barefoot and with different shoes; b) To assess the practical feasibility of the DS method for clinical applications., Materials and Methods: Eighteen healthy subjects were evaluated while walking barefoot at slow, natural and fast velocity. Shod walking was analysed at natural velocity. Four subjects were also analysed while walking in high-heel shoes. The power at the ankle joint was computed with both the AJ and the DS methods. We then compared the obtained results., Results: The DS method showed a consistent negative peak of power absorption during the load acceptance phase, barely visible with the AJ method. The maximum power production calculated with the DS method was significantly lower. The work at the end of the stride cycle was lower with the DS method, and in most conditions even negative, thus indicating higher energy dissipation., Significance: We confirmed on a large cohort of healthy subjects and in different walking conditions that neglecting foot deformations during gait leads to underestimate power absorption and overestimate power production. The DS method does not require a complex gait analysis protocol, nor additional time for the analysis, and can provide information of clinical interest, related to foot mechanical alterations., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Falls are one of the main concerns in people with Parkinson's disease, leading to poor quality of life and increased mortality. The sit-to-walk movement is the most frequent postural transition task during daily life and is highly demanding in terms of balance maintenance and muscular strength., Methods: With the aim of identifying biomechanical variables of high risk of falling, we investigated the sit-to-walk task performed by 9 Parkinson's disease patients with at least one fall episode in the six months preceding this study, 15 Parkinson's disease patients without previous falls, and 20 healthy controls. Motor performance was evaluated with an optoelectronic system and two dynamometric force plates after overnight suspension of all dopaminergic drugs and one hour after consumption of a standard dose of levodopa/benserazide., Findings: Poor trunk movements critically influenced the execution of the sit-to-walk movement in patients with a history of falling. The peak velocity of the trunk in the anterior-posterior direction discriminated faller from non-faller patients, with high specificity and sensitivity in both the medication-off and -on state., Interpretation: Our results confirm the difficulties in merging consecutive motor tasks in patients with Parkinson's disease. Trunk movements during the sit-to-walk can provide valuable measurements to monitor and possibly predict the risk of falling., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Previous studies have shown that, compared with non-stone formers, stone formers have a higher papillary density measured with computer tomography (CT) scan. The effect of increased hydration on such papillary density in idiopathic calcium stone formers is not known., Methods: Patients with recurrent calcium oxalate stones undergoing endourological procedures for renal stones at our Institution from June 2013 to June 2014 were considered eligible for enrolment. Enrolled patients underwent a baseline unenhanced CT scan before the urological procedure; after endoscopic removal of their stones, the patients were instructed to drink at least 2 L/day of a hypotonic, oligomineral water low in sodium and minerals (fixed residue at 180 °C < 200 mg/L) for at least 12 months. Finally, the patients underwent a follow-up unenhanced CT scan during hydration regimen., Results: Twenty-five patients were prospectively enrolled and underwent baseline and follow-up CT scans. At baseline, mean papillary density was 43.2 ± 6.6 Hounsfield Units (HU) (43.2 ± 6.7 for the left kidney and 42.8 ± 7.1 HU for the right kidney). At follow-up and after at least 12 months of hydration regimen, mean papillary density was significantly reduced at 35.4 ± 4.2 HU (35.8 ± 5.0 for the left kidney and 35.1 ± 4.2 HU for the right kidney); the mean difference between baseline and follow-up was - 7.8 HU (95% confidence interval - 10.6 to - 5.1 HU, p < 0.001)., Conclusions: Increased fluid intake in patients with recurrent calcium oxalate stones was associated with a significant reduction in renal papillary density., Trial Registration: NCT03343743 , 15/11/2017 (Retrospectively registered).

Levodopa-induced dyskinesias are a common and disabling side effect of dopaminergic therapy in Parkinson's disease, but their neural mechanisms in vivo are still poorly understood. Besides striatal pathology, the importance of cortical dysfunction has been increasingly recognized. The supplementary motor area in particular, may have a relevant role in dyskinesias onset given its involvement in endogenously generated actions. The aim of the present study was to investigate the levodopa-related cortical excitability changes along with the emergence of levodopa-induced peak-of-dose dyskinesias in subjects with Parkinson's disease. Thirteen patients without dyskinesias and ten with dyskinesias received 200/50 mg fast-acting oral levodopa/benserazide following overnight withdrawal (12 hr) from their dopaminergic medication. We targeted transcranial magnetic stimulation to the supplementary motor area, ipsilateral to the most dopamine-depleted striatum defined with single-photon emission computed tomography with [ 123 I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane, and recorded transcranial magnetic stimulation-evoked potentials with high-density electroencephalography before and at 30, 60, and 180 min after levodopa/benserazide intake. Clinical improvement from levodopa/benserazide paralleled the increase in cortical excitability in both groups. Subjects with dyskinesias showed higher fluctuation of cortical excitability in comparison to non-dyskinetic patients, possibly reflecting dyskinetic movements. Together with endogenous brain oscillation, levodopa-related dynamics of brain state could influence the therapeutic response of neuromodulatory interventions., (© 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Objectives: Impaired cerebral autoregulation following neurologic injury is a predictor of poor clinical outcome. We aimed to assess the relationship between body temperature and cerebral autoregulation in comatose patients., Design: Retrospective analysis of prospectively collected data., Setting: Neurocritical care unit of the Johns Hopkins Hospital., Patients: Eighty-five acutely comatose patients (Glasgow Coma Scale score of ≤ 8) admitted between 2013 and 2017., Interventions: None., Measurement and Main Results: Cerebral autoregulation was monitored using multimodal monitoring with near-infrared spectroscopy-derived cerebral oximetry index. Cerebral oximetry index was calculated as a Pearson correlation coefficient between low-frequency changes in regional cerebral oxygenation saturation and mean arterial pressure. Patients were initially analyzed together, then stratified by temperature pattern over the monitoring period: no change (< 1°C difference between highest and lowest temperatures; n = 11), increasing (≥ 1°C; n = 9), decreasing (≥ 1°C; n = 9), and fluctuating (≥ 1°C difference but no sustained direction of change; n = 56). Mixed random effects models with random intercept and multivariable logistic regression analysis were used to assess the association between hourly temperature and cerebral oximetry index, as well as between temperature and clinical outcomes. Cerebral oximetry index showed a positive linear relationship with temperature (β = 0.04 ± 0.10; p = 0.29). In patients where a continual increase or decrease in temperature was seen during the monitoring period, every 1°C change in temperature resulted in a cerebral oximetry index change in the same direction by 0.04 ± 0.01 (p < 0.001) and 0.02 ± 0.01 (p = 0.12), respectively, after adjusting for PaCO2, hemoglobin, mean arterial pressure, vasopressor and sedation use, and temperature probe location. There was no significant difference in mortality or poor outcome (modified Rankin Scale score of 4-6) between temperature pattern groups at discharge, 3, or 6 months., Conclusions: In acute coma patients, increasing body temperature is associated with worsening cerebral autoregulation as measured by cerebral oximetry index. More studies are needed to clarify the impact of increasing temperature on cerebral autoregulation in patients with acute brain injury.

The role of the subthalamic nucleus in human locomotion is unclear although relevant, given the troublesome management of gait disturbances with subthalamic deep brain stimulation in patients with Parkinson's disease. We investigated the subthalamic activity and inter-hemispheric connectivity during walking in eight freely-moving subjects with Parkinson's disease and bilateral deep brain stimulation. In particular, we compared the subthalamic power spectral densities and coherence, amplitude cross-correlation and phase locking value between resting state, upright standing, and steady forward walking. We observed a phase locking value drop in the β-frequency band (≈13-35Hz) during walking with respect to resting and standing. This modulation was not accompanied by specific changes in subthalamic power spectral densities, which was not related to gait phases or to striatal dopamine loss measured with [123I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane and single-photon computed tomography. We speculate that the subthalamic inter-hemispheric desynchronization in the β-frequency band reflects the information processing of each body side separately, which may support linear walking. This study also suggests that in some cases (i.e. gait) the brain signal, which could allow feedback-controlled stimulation, might derive from network activity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Objective: Critical care guidelines recommend a single target value for mean arterial blood pressure in critically ill patients. However, growing evidence regarding cerebral autoregulation challenges this concept and supports individualizing mean arterial blood pressure targets to prevent brain and kidney hypo- or hyperperfusion. Regional cerebral oxygen saturation derived from near-infrared spectroscopy is an acceptable surrogate for cerebral blood flow and has been validated to measure cerebral autoregulation. This study suggests a novel mechanism to construct autoregulation curves based on near-infrared spectroscopy-measured cerebral oximetry., Design: Case-series study., Setting: Neurocritical care unit in a tertiary medical center., Patients: Patients with acute neurologic injury and Glasgow coma scale score less than or equal to 8., Measurements and Main Results: Autoregulation curves were plotted using the fractional-polynomial model in Stata after multimodal continuous monitoring of regional cerebral oxygen saturation and mean arterial blood pressure. Individualized autoregulation curves of seven patients exhibited varying upper and lower limits of autoregulation and provided useful clinical information on the autoregulation trend (curves moving to the right or left during the acute coma period). The median lower and upper limits of autoregulation were 86.5 mm Hg (interquartile range, 74-93.5) and 93.5 mm Hg (interquartile range, 83-99), respectively., Conclusions: This case-series study showed feasibility of delineating real trends of the cerebral autoregulation plateau and direct visualization of the cerebral autoregulation curve after at least 24 hours of recording without manipulation of mean arterial blood pressure by external stimuli. The integration of multimodal monitoring at the bedside with cerebral oximetry provides a noninvasive method to delineate daily individual cerebral autoregulation curves.

Background: Transcranial Doppler (TCD) noninvasively measures cerebral blood flow (CBF) velocity and is a well-studied method to monitor cerebral autoregulation (CA). Near-infrared spectroscopy (NIRS) has emerged as a promising noninvasive method to determine CA continuously by using regional cerebral oxygen saturation (rSO 2 ) as a surrogate for CBF. Little is known about its accuracy to determine CA in patients with intracranial lesions. The purpose of this study was to assess the accuracy of rSO 2 -based CA monitoring with TCD methods in comatose patients with acute neurological injury., Methods: Thirty-three comatose patients were monitored at the bedside to measure CA using both TCD and NIRS. Patients were monitored daily for up to three days from coma onset. The cerebral oximetry index (COx) was calculated as the moving correlation between the slow waves of rSO 2 and mean arterial pressure (MAP). The mean velocity index (Mx) was calculated as a similar coefficient between slow waves of TCD-measured CBF velocity and MAP. Optimal blood pressure was defined as the MAP with the lowest Mx and COx. Averaged Mx and COx as well as optimal MAP, based on both Mx and COx, were compared using Pearson's correlation. Bias analysis was performed between these same CA metrics., Results: The median duration of monitoring was 60 min (interquartile range [IQR] 48-78). There was a moderate correlation between the averaged values of COx and Mx (R = 0.40, p = 0.005). Similarly, there was a strong correlation between optimal MAP calculated for COx and Mx (R = 0.87, p < 0.001). Bland-Altman analysis showed moderate agreement with bias (±standard deviation) of -0.107 (±0.191) for COx versus Mx and good agreement with bias of 1.90 (±7.94) for optimal MAP determined by COx versus Mx., Conclusions: Monitoring CA with NIRS-derived COx is correlated and had good agreement with previously validated TCD-based method. These results suggest that COx may be an acceptable substitute for Mx monitoring in patients with acute intracranial injury.

Purpose: The purpose of the study was to assess adjuvant treatment with topical nonsteroidal anti-inflammatory drugs (NSAIDs) (0.9 % bromfenac, 0.1 % nepafenac, 0.5 % indomethacin, or 0.1 % diclofenac) in addition to topical steroidal treatment with 0.1 % dexamethasone and 0.3 % netilmicin for prevention of cystoid macular edema (CME) after uneventful small incision cataract extraction with foldable intraocular lens (IOL) implantation., Setting: Institute of Ophthalmology, Department of Scienze Mediche di Base, Neuroscienze ed Organi di Senso, Aldo Moro University, Policlinico Consorziale di Bari, Bari, Italy., Design: A retrospective 6-month single center study., Methods: Patients were divided into groups according to treatment with topical drugs for 2 weeks, after phacoemulsification with foldable IOL implantation. CME incidence was evaluated by assessing retinal foveal thickness changes using spectral domain optical coherence tomography. All patients were treated with a fixed combination of dexamethasone and netilmicin, and some patients were additionally treated with NSAIDs (bromfenac, nepafenac, indomethacin, or diclofenac)., Results: Fourteen patients were treated with bromfenac, 15 with nepafenac, 12 with indomethacin, and 14 with diclofenac; ten patients were treated with dexamethasone and netilmicin alone. At the end of the follow-up, macular thickness, evaluated at 1-week post-surgery, was reduced only in the group treated with nepafenac (-1.3 %, p = 0.048), was increased in the group treated with dexamethasone and netilmicin alone (+4.3 %, p = 0.04), and did not change in the groups treated with bromfenac (-1.1 %, p = 0.3), indomethacin (+0.1 %, p = 0.19), or diclofenac (+1.2 %, p = 0.74). There were no side effects in any group., Conclusions: Topical treatment with nepafenac, bromfenac, and indomethacin enhanced the efficacy of steroids to reduce postoperative macular edema. Diclofenac did not improve steroids efficacy.

We report and correct errors in our recently published paper [J. Opt. Soc. Am. A32, 1403 (2015)10.1364/JOSAA.32.001403JOAOD61084-7529].

Laser interferometry, as applied in cutting-edge length and displacement metrology, requires detailed analysis of systematic effects due to diffraction, which may affect the measurement uncertainty. When the measurements aim at subnanometer accuracy levels, it is possible that the description of interferometer operation by paraxial and scalar approximations is not sufficient. Therefore, in this paper, we place emphasis on models based on nonparaxial vector beams. We address this challenge by proposing a method that uses the Huygens integral to propagate the electromagnetic fields and ray tracing to achieve numerical computability. Toy models are used to test the method's accuracy. Finally, we recalculate the diffraction correction for an interferometer, which was recently investigated by paraxial methods.

A study of West Nile virus (WNV) ecology was conducted in St. Tammany Parish, Louisiana, from 2002 to 2004. Mosquitoes were collected weekly throughout the year using Centers for Disease Control and Prevention (CDC) light traps placed at 1.5 and 6 m above the ground and gravid traps. A total of 379,466 mosquitoes was collected. WNV was identified in 32 pools of mosquitoes comprising four species; 23 positive pools were from Culex nigripalpus collected during 2003. Significantly more positive pools were obtained from Cx. nigripalpus collected in traps placed at 6 m than 1.5 m that year, but abundance did not differ by trap height. In contrast, Cx. nigripalpus abundance was significantly greater in traps placed at 6 m in 2002 and 2004. Annual temporal variation in Cx. nigripalpus peak seasonal abundance has important implications for WNV transmission in Louisiana. One WNV-positive pool, from Cx. erraticus, was collected during the winter of 2004, showing year-round transmission. The potential roles of additional mosquito species in WNV transmission in southeastern Louisiana are discussed.

This paper is a study of surface effects, e.g. roughness or asymmetrical cut, in the Laue diffraction of X-rays by crystals, based on the Takagi-Taupin equations. By means of Riemann-Green integrals, first a formal solution has been obtained when the entrance and the exit surfaces are arbitrary. Then a coordinate transformation mapping a propagation domain with arbitrary boundaries into a rectangular domain with straight boundaries is given. Potential measurement errors in \gamma-ray wavelength and silicon lattice-parameter measurements by double-crystal diffractometry and X-ray interferometry, respectively, are outlined and anticipated by studying, in the two-wave approximation, the reflection peak shift and extra phase originating from an asymmetrically cut crystal. A relationship between analyser displacement, interferometer-signal phase and relative uncertainty in lattice-parameter measurement is also given.

X-ray diffraction in continuously deformed crystals is considered by application of Fourier optics and from the viewpoint of the analogy between X-ray dynamics and the motion of two-level systems in quantum mechanics. Different forms of Takagi's equations are traced back to a common framework and it is shown that they are different ways to represent the same propagation equation. A novel way to solve Takagi's equations in the presence of a constant strain gradient is presented and approximation methods derived from quantum mechanics are considered. Crystal deformation in X-ray interferometry and two-crystal spectrometry are discussed and it is demonstrated that Si lattice-parameter measurements depend on the diffracting plane spacing on the crystal surface.

We describe the interaction of the neodymium: yttrium aluminum garnet (Nd:YAG) laser energy with intraocular lenses using the laser in the Q-switched mode. Using this method, it is possible to treat opacities that eventually might occur at the level of the visual axis on the optic faces of polymethylmethacrylate intraocular lenses (IOLs) if safety parameters (perfect focusing, use of additional lenses, and slight and continuous movement of the focal point of the laser) are followed. However, it is not possible to treat the silicone IOLs with the Nd:YAG laser because the threshold values for damage to the IOL are lower than the energy values required for destroying the capsular opacities on the optic axis.

The authors reported a culturally proven case of orbital cellulitis, uveitis and conjunctivitis due to Yersinia enterocolitica serotype 0:9. This case, in addition to the previously reported, remarks the importance of Yersinia enterocolitica as ocular pathogen.