Assessment of the Corticospinal Tract Profile in Pure Lower Motor Neuron Disease: A Diffusion Tensor Imaging Study

AIM

The aim of this study was to evaluate the corticospinal tract (CST) diffusion profile in pure lower motor neuron disease (pLMND) patients who at baseline did not show any clinical or electrophysiological involvement of upper motor neurons (UMN), and in amyotrophic lateral sclerosis (ALS) patients.

MATERIALS AND METHODS

Fifteen ALS patients with delayed central motor conduction time (CMCT) and 14 pLMND patients with normal CMCT were enrolled together with 15 healthy controls. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) maps were obtained. The tract profile of CST was reconstructed with the automated fiber quantification tool and its diffusion properties were quantified voxel-by-voxel and then compared pairwise between groups. Moreover, a random forest (RF) classifier was trained to evaluate the ability of CST diffusion metrics in distinguishing pairwise the groups from the controls.

RESULTS

ALS patients presented wide microstructural abnormalities in the entire CST as assessed by FA decrease and RD increase while pLMND patients showed focal FA decrease and a larger AD increase in the cerebral peduncle and posterior limb of the internal capsule in comparison with controls. RF revealed that diffusion tensor imaging (DTI) metrics accurately distinguished ALS patients and pLMND patients from controls (96.67 and 95.71% accuracy, respectively).

CONCLUSIONS

Our study demonstrates that the CST was impaired in both ALS and pLMND patients, thus suggesting that DTI metrics are a reliable tool in detecting subtle changes of UMN in pLMND patients, also in the absence of clinical and CMCT abnormalities.

Neurobiology of placebo effect in Parkinson's disease: What we have learned and where we are going

The placebo effect is a phenomenon produced when an inert substance administered like a regular treatment improves the clinical outcome. Parkinson's disease (PD) is one of the main clinical disorders for which the placebo response rates are high. The first evidence of the neurobiological mechanisms underlying the placebo effect in PD stems from 2001, when de la Fuente-Fernandez and colleagues demonstrated that a placebo injection led to the release of dopamine in the striatal nuclei of PD measured with positron emission tomography technology. Since then, several studies have been conducted to investigate the neurobiological underpinnings of placebo responses. This article presents a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Of an initial yield of 143 papers, 19 were included. The lessons learned from these studies are threefold: (i) motor improvement is dependent on the activation of the entire nigrostriatal pathway induced by dopamine release in the dorsal striatum; (ii) the magnitude of placebo-induced effects is modulated by an expectancy of improvement, which is in turn related to the release of dopamine within the ventral striatum; (iii) the functioning of the neural pathways underlying the placebo response can be tuned by prior exposure and learning strategies. In conclusion, although the neural network underlying the placebo effect in PD has been largely confirmed and accepted, what remains to be established is how, when, and where the expectation of reward (mediated by the ventral striatum) interacts with the primary motor system (mediated by the dorsal striatum) to induce clinical improvement in motor symptoms. © 2018 International Parkinson and Movement Disorder Society.

Usefulness of cardiac parasympathetic index in CPAP-treated patients with obstructive sleep apnea: A preliminary study

Cardiac autonomic indexes, including cardiac parasympathetic index and cardiac sympathetic index, have been reported to accurately identify patients with sleep disorders such as obstructive sleep apnea. Our study aimed to assess cardiac autonomic indexes in patients with obstructive sleep apnea before and during a single full-night continuous positive airway pressure therapy using a combined approach. Our simultaneous heart rate variability-polysomnographic study included 16 never-treated obstructive sleep apnea patients. Two patients dropped out. Patients underwent combined recordings in two consecutive days, at baseline and during a single full-night of acute continuous positive airway pressure treatment. We calculated cardiac parasympathetic index and cardiac sympathetic index as night/day ratio for high-frequency and low-frequency heart rate variability spectral components, respectively. Continuous positive airway pressure treatment significantly reduced cardiac autonomic indexes values in comparison with baseline values (cardiac parasympathetic index: p < .0001; cardiac sympathetic index: p = .001). After acute continuous positive airway pressure treatment, the percentage of decrease of cardiac parasympathetic index was greater than that of cardiac sympathetic index (51.02 ± 15.72 versus 34.64 ± 26.93). A positive statistical correlation was also found between decrease of cardiac parasympathetic index and decrease of apnea-hypopnea index after continuous positive airway pressure (p < .001). This study improves the knowledge on cardiac autonomic modulation during acute continuous positive airway pressure therapy in obstructive sleep apnea. Our results demonstrate that both autonomic indexes decreased significantly after a single-night of acute continuous positive airway pressure therapy. Cardiac parasympathetic index more than cardiac sympathetic index was related to decrease of apnea-hypopnea index after continuous positive airway pressure therapy, thus representing a potential help in everyday clinical practice.

Functional activity changes in memory and emotional systems of healthy subjects with déjà vu

Déjà vu (DV) is a fascinating and mysterious human experience that has attracted interest from psychologists and neuroscientists for over a century. In recent years, several studies have been conducted to unravel the psychological and neurological correlates of this phenomenon. However, the neural mechanisms underlying the DV experience in benign manifestations are still poorly understood. Thirty-three healthy volunteers completed an extensive neuropsychiatric and neuropsychological battery including personality evaluation. The presence of DV was assessed with the Inventory for Deja vu Experiences Assessment. Participants underwent episodic memory learning test, and 2 days later during event-related functional magnetic resonance imaging (fMRI), they are asked to rate old and new pictures as a novel, moderately/very familiar, or recollected. We identified 18 subjects with DV (DV+) and 15 without DV (DV-) matched for demographical, neuropsychological, and personality characteristics. At a behavioral level, no significant difference was detected in the episodic memory tasks between DV+ and DV-. Functional magnetic resonance imaging analysis revealed that DV+, independently from task conditions, were characterized by increased activity of the bilateral insula coupled with reduced activation in the right parahippocampal, both hippocampi, superior/middle temporal gyri, thalami, caudate nuclei, and superior frontal gyri with respect to DV-. Our study demonstrates that individuals who experienced DV are not characterized by different performance underlying familiarity/recollection memory processes. However, fMRI results provide evidence that the physiological DV experience is associated with the employment of different neural responses of brain regions involved in memory and emotional processes.

Characterization of the Effects of a Six-Month Dancing as Approach for Successful Aging

Aging is accompanied by a decline in multiple domains. Positive effects of dance practice on several health issues have been evaluated in young adults, while the effects of regular social dance practice on physical fitness, sexual health, and cognitive functions have not been studied yet in older experienced dancers. Thus, the aim of this study has been to investigate whether a 6-month social dance practice might influence fitness performance, sexual health, and specific cognitive functions and/or mood characteristics in older experienced dancers. Thirty experienced dancers (age: 71.2±5.1 years, 18 females/12 males) were enrolled from the dance school "NonSoloLiscio" of Catanzaro. Body composition, physical fitness, sexual health, and cognitive functions were assessed before (T0) and after (T6) intervention. After 6 months of dance practice, percent of fat mass (%FM) significantly decreased (p<0.01), while fat-free mass (FFM) significantly increased (p<0.01) in both genders. Moreover, significant main effects of time on physical fitness tests, such as chair stand test (CST) (p<0.01), gait speed (p<0.05), and timed up and go (p<0.05), were found. Sexual health was significantly higher in males than in females at T0 and no significant effects of dance on subjects' sexual health were found. Interestingly, trait of anxiety significant decreased (p<0.05) and perception of retrospective memory significantly increased (p=0.05) after training independently of gender. Our preliminary results suggest that, even in older intermediate-level dancer, the practice of social dance might positively influence body composition and also increase fitness performance, memory functions, and anxiety. In contrast, no effects on sexual health were observed after 6 months of dancing.

Gender difference and correlation between sexuality, thyroid hormones, cognitive, and physical functions in elderly fit

PURPOSE

Sexuality in the elderly is related to psycho-physical well-being. Aim of this study was to analyze the correlation between sexual health, thyroid hormones, cognitive functions, and physical fitness in elderly population.

METHODS

Fifty-one fit adults were recruited (age: 71.9 ± 5.3 years, 26 females and 25 males). Sexuality was evaluated using the Changes in Sexual Functioning Questionnaire-short form (CSFQ-14) and the Sexual Attitude Scale (SAS). Thyroid function was assessed by measuring serum TSH, FT3, and FT4. Cognitive functions and depressive symptoms were evaluated by the Mini Mental State Examination (MMSE) test and Geriatric Depression Scale (GDS) scores. Subjects' physical fitness was evaluated using the following tests: Short Physical Performance Battery (SPPB), Handgrip test (HG), Timed Up and Go test (TUG), and 2-Minute step test (ST).

RESULTS

CSFQ-14 positively correlated with MMSE (p < 0.05) and negatively with GDS (p < 0.05), while thyroid function was not correlated with sexuality, in both genders. A negative relationship between FT4 vs. weight, FT3 vs. HG and FT3/FT4 ratio vs. ST were found (p = 0.05) in females, while in males, it occurred for TSH vs. TUG (p < 0.05); a positive relationship existed in females between FT4 vs. ST (p < 0.05). Finally, CSFQ-14 was significantly correlated with SPPB (p < 0.05), CST, TUG, and ST (p < 0.01), in both genders.

CONCLUSION

We demonstrated a strict relationship between active sexuality, preserved cognitive function and appropriate physical fitness in elderly subjects, independently from gender. Our preliminary data suggest that in elderly fit population, peripheral thyroxin deiodination may be a useful predictor of better physical performance and more successful aging.

A multicenter retrospective study of charcot-marie-tooth disease type 4B (CMT4B) associated with mutations in myotubularin-related proteins (MTMRs)

OBJECTIVE

Charcot-Marie-Tooth (CMT) disease 4B1 and 4B2 (CMT4B1/B2) are characterized by recessive inheritance, early onset, severe course, slowed nerve conduction, and myelin outfoldings. CMT4B3 shows a more heterogeneous phenotype. All are associated with myotubularin-related protein (MTMR) mutations. We conducted a multicenter, retrospective study to better characterize CMT4B.

METHODS

We collected clinical and genetic data from CMT4B subjects in 18 centers using a predefined minimal data set including Medical Research Council (MRC) scores of nine muscle pairs and CMT Neuropathy Score.

RESULTS

There were 50 patients, 21 of whom never reported before, carrying 44 mutations, of which 21 were novel and six representing novel disease associations of known rare variants. CMT4B1 patients had significantly more-severe disease than CMT4B2, with earlier onset, more-frequent motor milestones delay, wheelchair use, and respiratory involvement as well as worse MRC scores and motor CMT Examination Score components despite younger age at examination. Vocal cord involvement was common in both subtypes, whereas glaucoma occurred in CMT4B2 only. Nerve conduction velocities were similarly slowed in both subtypes. Regression analyses showed that disease severity is significantly associated with age in CMT4B1. Slopes are steeper for CMT4B1, indicating faster disease progression. Almost none of the mutations in the MTMR2 and MTMR13 genes, responsible for CMT4B1 and B2, respectively, influence the correlation between disease severity and age, in agreement with the hypothesis of a complete loss of function of MTMR2/13 proteins for such mutations.

INTERPRETATION

This is the largest CMT4B series ever reported, demonstrating that CMT4B1 is significantly more severe than CMT4B2, and allowing an estimate of prognosis. ANN NEUROL 2019.

The discovery of beri-beri and scurvy vitamins - two hundred and two years from its discovery

The history of the discovery of vitamins was the history of their deficiency disorders. Casimir Funk, the father of vitaminic therapy, studied the interrelationships in the human body of those elements that Christiaan Eijkman demonstrated in animals, particularly birds. In 1911, he designated these factors vitamins (vita = life and amine, a nitrogenous substance essential for life); this name was accepted by the scientific community in 1912. Here, we intend to give an illustrative view on the early days of vitamin research as carried out by Casimir Funk.

Color vision study to assess the impaired retina-brain cortex pathway in type 2 diabetes: a pilot study in Calabria (Southern Italy)

The present pilot study was undertaken to investigate the impaired acquired color vision on Calabrian male sample showing this parameter as a biological marker in type 2 diabetes. All patients and controls underwent three pseudo-isochromatic clinical test batteries: Ishihara test, Farnsworth test, and City University test. The results show a specific loss of short-wavelength (blue sensitivity) and typical tritan responses in diabetic patients. Generally, in later stages of the disease, the red-green mechanisms are involved. By the impaired color vision study in diabetic patients, we can confirm the impaired retina-brain cortex pathway. We believe that the above not invasive test analysis can support the other instrumental and imaging analysis to study the impaired retina-brain cortex pathway. Moreover, we think that the present clinical method can be useful in terms of preventive medicine.

REM-Sleep Behavior Disorder in Patients With Essential Tremor: What Is Its Clinical Significance?

Objective: REM sleep behavior disorder (RBD) is an important risk factor for the dementia development and for the deterioration of autonomic functions in patients with Parkinson's Disease. RBD has also been reported in patients with Essential Tremor (ET). However, its clinical significance in ET remains still unknown. We aimed to investigate clinical, neuropsychological and cardiac autonomic scintigraphic differences between ET patients with and without RBD.

Methods: To assess RBD symptoms, RBD Single-Question has been administered in a cohort of 55 patients with a clinical diagnosis of ET. Patients with clinical RBD underwent polysomnography (PSG) confirmation. All patients completed a battery of neuropsychological assessment of memory, executive function, attention, language, and visuospatial function. Cardiac MIBG scintigraphy was performed in order to measure the cardiac autonomic innervation.

Results: Ten ET patients (18%) had a PSG-confirmed RBD (ET^RBD+). Compared to ET patients without RBD (ET^RBD−), significantly reduced scores on memory domain tests such as Rey auditory verbal learning test immediate recall (p = 0.015) and Rey auditory verbal learning test delayed recall (p = 0.004) and phonemic fluency test (p = 0.028) were present in ET^RBD+. By contrast, no other significant clinical difference has emerged from the comparison between two ET groups. Similarly, ET^RBD+ patients have cardiac MIBG tracer uptake in the normal value range as occurred in those with ET^RBD−.

Conclusions: This study improves the knowledge on clinical significance of RBD symptoms in ET patients. Our preliminary findings demonstrate that presence of RBD in ET is associated with neurocognitive impairment, but not with cardiac autonomic dysfunction. Further longitudinal studies are needed to investigate whether ET patients with RBD will develop a frank dementia over the time.

Imaging counterpart of postural instability and vertical ocular dysfunction in patients with PSP: A multimodal MRI study

INTRODUCTION

We investigated the imaging counterpart of two functional domains (ocular motor dysfunction and postural instability) in progressive supranuclear palsy (PSP) patients classified according to the new clinical diagnostic criteria.

METHODS

Forty-eight patients with probable PSP-Richardson's syndrome (PSP-RS), 30 with probable PSP-parkinsonism (PSP-P), 37 with Parkinson's disease (PD), and 38 controls were enrolled. For each functional domain, PSP patients were stratified by two certainty levels: vertical supranuclear gaze palsy (O1) and slowness of vertical saccades (O2) for ocular motor dysfunction; early unprovoked falls and tendency to fall on the pull-test for postural instability. Voxel-based morphometry (VBM), whole-brain fractional anisotropy (FA) and MR planimetric measurements were analysed and compared across patient groups.

RESULTS

O1 was present in 64%, and O2 in 36% of all PSP patients. All PSP-RS patients showed early unprovoked falls. TBSS whole-brain analysis revealed that superior cerebellar peduncles (SCPs) were the only structures with significantly lower FA values in PSP-RS compared with PSP-P patients. PSP/O1 patients had lower FA values in midbrain than PSP/O2 patients. By contrast, VBM revealed no differences in grey matter volume between PSP patient groups. MR Planimetric measurements confirmed atrophy of midbrain and SCPs, in line with DTI findings.

CONCLUSIONS

Our study demonstrates that SCPs were significantly more damaged in patients with PSP-RS in comparison with PSP-P patients, thus suggesting the role of SCPs in developing postural instability. Midbrain damage was less severe in O2 than in O1 patients, suggesting that the degree of vertical ocular dysfunction reflects the severity of midbrain atrophy.

Refining initial diagnosis of Parkinson's disease after follow-up: A 4-year prospective clinical and magnetic resonance imaging study

Background

No prospective study of patients with Parkinson's disease (PD) has investigated the appearance of vertical gaze abnormalities, a feature suggestive of progressive supranuclear palsy (PSP).

Objective

To identify, within a cohort of patients with an initial diagnosis of PD, those who developed vertical gaze abnormalities during a 4‐year follow‐up, and to investigate the performance of new imaging biomarkers in predicting vertical gaze abnormalities.

Methods

A total of 110 patients initially classified as PD and 74 controls were enrolled. All patients underwent clinical assessment at baseline and every year up to the end of the follow‐up. The pons/midbrain area ratio 2.0 and the Magnetic Resonance Parkinsonism Index 2.0 were calculated.

Results

After 4‐year follow‐up, 100 of 110 patients maintained the diagnosis of PD, whereas 10 PD patients (9.1%) developed vertical gaze abnormalities, suggesting an alternative diagnosis of PSP‐parkinsonism. At baseline, the Magnetic Resonance Parkinsonism Index 2.0 was the most accurate biomarker in differentiating PD patients who developed vertical gaze abnormalities from those who maintained an initial diagnosis of PD. At the end of follow‐up, both of these biomarkers accurately distinguished PSP‐parkinsonism from PD.

Conclusions

Our results demonstrate that a number of patients with an initial diagnosis of PD developed vertical gaze abnormalities during a 4‐year follow‐up, and the diagnosis was changed from PD to PSP‐parkinsonism. In PD patients, baseline Magnetic Resonance Parkinsonism Index 2.0 showed the best performance in predicting the clinical evolution toward a PSP‐parkinsonism phenotype, enabling PSP‐parkinsonism patients to be identified at the earliest stage of the disease for promising disease‐modifying therapies. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Periventricular white matter changes in idiopathic intracranial hypertension

Objective

To evaluate whether increased cerebrospinal fluid (CSF) pressure causes alteration of periventricular white matter (WM) microstructure in patients with idiopathic intracranial hypertension (IIH).

Methods

In a prospective study, patients with refractory chronic headache with and without IIH performed a neuroimaging study including 3T MRI, 3D Phase Contrast MR venography, and diffusion tensor imaging (DTI) of the brain. Whole‐brain voxel‐wise comparisons of DTI abnormalities of WM were performed using tract‐based spatial statistics. A correlation analysis between DTI indices and CSF opening pressure, highest peak, and mean pressure was also performed in patients with IIH.

Results

We enrolled 62 consecutive patients with refractory chronic headaches. Thirty‐five patients with IIH, and 27 patients without increased intracranial pressure. DTI analysis revealed no fractional anisotropy changes, but decreased mean, axial, and radial diffusivity in body (IIH_MD = 0.80 ± 0.04, non‐IIH_MD = 0.84 ± 0.4, IIH_AD = 1.67 ± 0.07, non‐IIH_AD = 1.74 ± 0.05, IIH_RD = 0.38 ± 0.04, non‐IIH_RD = 0.42 ± 0.05 [mm²/sec × 10⁻³]) of corpus callosum, and in right superior corona radiata (IIH_MD = 0.75 ± 0.04, non‐IIH_MD = 0.79 ± 0.05, IIH_AD = 1.19 ± 0.07, non‐IIH_AD = 1.28 ± 0.09, IIH_RD = 0.59 ± 0.03, non‐IIH_RD = 0.53 ± 0.03 [mm²/sec × 10⁻³]) of 35 patients with IIH compared with 27 patients without increased intracranial pressure. DTI indices were negatively correlated with high CSF pressures (P < 0.05). After medical treatment, eight patients showed incremented MD in anterior corona radiata left and right and superior corona radiata right.

Conclusions

There is significant DTI alteration in periventricular WM microstructure of patients with IIH suggesting tissue compaction correlated with high CSF pressure. This periventricular WM change may be partially reversible after medical treatment.

Cerebrospinal Fluid Pressure-Related Features in Chronic Headache: A Prospective Study and Potential Diagnostic Implications

Objective: To identify the pressure-related features of isolated cerebrospinal fluid hypertension (ICH) in order to differentiate headache sufferers with ICH from those with primary headache disorder. Methods: In this prospective study, patients with refractory chronic headaches and suspected of having cerebrospinal fluid-pressure elevation without papilledema or sixth nerve palsy, together with controls, underwent 1-h lumbar cerebrospinal fluid pressure monitoring via a spinal puncture needle. Results: We recruited 148 consecutive headache patients and 16 controls. Lumbar cerebrospinal fluid pressure monitoring showed high pressure and abnormal pressure pulsations in 93 (63 %) patients with headache: 37 of these patients with the most abnormal pressure parameters (opening pressure above 250 mm H₂O, mean pressure 301 mm H₂O, mean peak pressure 398 mm H₂O, and severe abnormal pressure pulsations) had the most severe headaches and associated symptoms (nocturnal headache, postural headache, transient visual obscuration); 56 patients with the less abnormal pressure parameters (opening pressure between 200 and 250 mm H₂O, mean pressure 228 mm H₂O, mean peak pressure 316 mm H₂O, and abnormal pressure pulsations) had less severe headaches and associated symptoms. Conclusions: Nocturnal and postural headache, and abnormal pressure pulsations are the more common pressure-related features of ICH in patients with chronic headache. Abnormal pressure pulsations may be considered a marker of ICH in chronic headache.