Federica Provini

Sleep-related stridor due to dystonic vocal cord motion and neurogenic tachypnea/tachycardia in multiple system atrophy.

Sleep‐disordered breathing and sleep‐related motor phenomena are part of the clinical spectrum of multiple system atrophy (MSA). Stridor has been attributed to denervation of laryngeal muscles or instead to dystonic vocal cord motion. We studied 3 patients with nocturnal stridor in the setting of MSA. All patients underwent nocturnal videopolysomnography (VPSG) with breathing and heart rate, O2 saturation and intra‐esophageal pressure recordings, and simultaneous EMG recordings of the posterior cricoarytenoid, cricothyroid, and thyroarytenoid muscles and continuous vocal cord motion evaluation by means of fiberoptic laryngoscopy. VPSG/EMG and fiberoptic laryngoscopy documented normal vocal cord motion without denervation during wake and stridor only during sleep when hyperactivation of vocal cords adductors appeared in the absence of significant O2 desaturation. All patients had tachycardia and tachypnea and paradoxical breathing during sleep, erratic intercostalis and diaphragmatic EMG activity and Rem sleep behavior disorder. One of the patients had restless legs syndrome with periodic limb movement during sleep and excessive fragmentary hypnic myoclonus. In conclusion, our patients with MSA had nocturnal stridor due to sleep‐related laryngeal dystonia. Stridor was associated with other abnormal sleep‐related respiratory and motor disorders, suggesting an impairment of homeostatic brainstem integration in MSA.

Cardiovascular disorders and obstructive sleep apnea syndrome

The first polysomnographic recordings with concomitant monitoring of cardiocirculatory parameters demonstrated that obstructive apneas arising during sleep are accompanied by a marked increase in pulmonary and systemic arterial pressure and severe alveolar hypoventilation. Apneas also may give rise to cardiac arrhythmias, namely potentially life-threatening bradyarrhythmias. The long-term repercussions of these nocturnal cardiocirculatory changes on subsequent cardiovascular diseases and the patients life expectancy are more controversial. There is little doubt that patients with obstructive sleep apnea syndrome (OSAS) have systemic arterial hypertension, ischemic heart disease, transient ischemic attacks, or stroke more often than control populations and have a shorter life expectancy. However, these clinical manifestations may be at least partly due to myriad other risk factors almost always present in OSAS patients (in particular obesity, diabetes, alcoholism, and cigarette smoking). Few multivariate epidemiological surveys have addressed all these confounding factors. The effectiveness of continuous positive airway pressure treatment in reducing the incidence of cardiovascular comorbidity in OSAS patients is not disputed, even though controlled epidemiological surveys on large populations are scant. This overview of cardiovascular disorders and OSAS examines the latest literature findings aimed at establishing the true impact of nocturnal apneas on cardiocirculatory disease (systemic arterial hypertension, ischemic heart disease, stroke, pulmonary hypertension and right heart failure and mortality).

Visual and computer-based detection of slow eye movements in overnight and 24-h EOG recordings.

OBJECTIVEnThe present work aimed to evaluate the performance of an automatic slow eye movement (SEM) detector in overnight and 24-h electro-oculograms (EOG) including all sleep stages (1, 2, 3, 4, REM) and wakefulness.nnnMETHODSnTen overnight and five 24-h EOG recordings acquired in healthy subjects were inspected by three experts to score SEMs. Computerized EOG analysis to detect SEMs was performed on 30-s epochs using an algorithm based on EOG wavelet transform, recently developed by our group and initially validated by considering only pre-sleep wakefulness, stages 1 and 2.nnnRESULTSnThe validation procedure showed the algorithm could identify epochs containing SEM activity (concordance index k=0.62, 80.7% sensitivity, 63% selectivity). In particular, the experts and the algorithm identified SEM epochs mainly in pre-sleep wakefulness, stage 1, stage 2 and REM sleep. In addition, the algorithm yielded consistent indications as to the duration and position of SEM events within the epoch.nnnCONCLUSIONSnThe study confirmed SEM activity at physiological sleep onset (pre-sleep wakefulness, stage 1 and stage 2), and also identified SEMs in REM sleep. The algorithm proved reliable even in the stages not used for its training.nnnSIGNIFICANCEnThe study may enhance our understanding of SEM meaning and function. The algorithm is a reliable tool for automatic SEM detection, overcoming the inconsistency of manual scoring and reducing the time taken by experts.

Sleep-related faciomandibular myoclonus: A sleep-related movement disorder different from bruxism.

We describe a 33‐year‐old man who presented with lip and tongue nibbling and bleeding during sleep. Videopolysomnography revealed myoclonic jerks involving the masticatory and facial muscles recurring mainly during NREM sleep. There was no tonic EMG masticatory activity typical of bruxism. EMG analysis demonstrated the recruitment of V‐ to VII innervated muscles and, in half of the episodes, also the sternocleidomastoideus. Our patient had sleep‐related faciomandibular myoclonus (SFMM) with spontaneous jerks of oromasticatory and cervical muscles, occurring only during sleep. Tooth grinding, temporomandibular joint pain, abnormal tooth mobility, tooth wear, and other dental problems were clinically absent. We propose that, on the basis of the clinical and EMG features, SFMM may be considered a distinct disorder and different from sleep bruxism.

RLS, PLM, and their differential diagnosis—A video guide

This video guide has been designed as an introduction to the full spectrum of nocturnal presentations of restless legs syndrome (RLS) and periodic limb movements (PLM), and to their differential diagnoses. The DVD consists of four sections: In the first part, clinical presentations of RLS are covered (videos 1–3). In the second part, the variety of typical and less frequent presentations of PLM are demonstrated (videos 4–14). The third part shows the clinical presentation of augmentation (videos 15–19). The last section is dedicated to the differential diagnosis of RLS and PLM and demonstrates nocturnal manifestations of other motor disorders during sleep, which must be distinguished: Epilepsy, parasomnias, and other movement disorders (of sleep) (videos 20–33). After viewing this DVD, the reader should be able to: (1) appreciate the spectrum of voluntary and unvoluntary movements seen in patients with RLS during wakefulness; (2) recognize typical PLM during sleep in subjects with RLS, and appreciate the enormous variability of clinical presentations of PLM; (3) describe specific and distinct aspects of motor activity in augmentation in patients with RLS; and (4) be aware of the most important differential diagnosis of RLS/PLM from a video or nocturnal motor activity point of view, namely, nocturnal epilepsy, parasomnias, and others.

Sleep-wake and body core temperature rhythms in multiple sclerosis with fatigue

OBJECTIVEnTo study sleep-wake and body core temperature (BCT) circadian rhythms in patients with multiple sclerosis (MS)-associated with chronic fatigue.nnnMETHODSnSix relapsing-remitting MS patients with chronic fatigue underwent 48 consecutive hours polysomnography (PSG) with BCT measurement, followed by a Multiple Sleep Latency Test (MSLT). All patients were relapse- and drug-free. Mood depression, brain and cervical cord enhanced MRI, dynamic spirometry and Fatigue Severity Scale (FSS) were assessed just before PSG.nnnRESULTSnIn all patients mood depression was absent and dynamic spirometry normal, but FSS confirmed fatigue. MRI showed non-enhancing lesions. Nocturnal sleep was characterized by normal architecture and mean sleep efficiency was only slightly reduced. Arousal index was normal and periodic limb movements during sleep (PLMS) were present in four patients, with an increased index (PLMS-I) in only two of them. Upon MSLT, mean sleep latency was normal in all patients with one sleep onset REM period in one patient. All patients displayed a normal BCT 24-h rhythm. Mesor, amplitude and acrophase of BCT rhythm did not show significant differences between MS and controls.nnnCONCLUSIONSnWe found substantially normal sleep-wake and BCT rhythmicity in six patients with MS and fatigue. Non-restorative sleep and abnormal BCT regulation were unlikely mechanisms of chronic fatigue in our MS patients.nnnSIGNIFICANCEnSubjective fatigue and abnormal sleep and BCT can be independent manifestation in MS patients. The findings support the notion that objective measures of fatigue comparable to the MSLT for sleepiness do not exist.

Wavelet Analysis of Electroencephalographic and Electro-Oculographic Changes During the Sleep Onset Period

This study investigates the relationship between changes in the electroencephalogram (EEG) and slow eye movements (SEMs) in the electro-oculogram (EOG) at the wake-sleep transition. Analysis of EEG and EOG is performed by the discrete wavelet transform and utilizes energy functions built within the multiresolution framework. In particular, SEMs are detected automatically by a computerized system, previously developed and validated; core of the system is a function of EOG energies at different scales of decomposition, which defines SEMs in rigorous energetic terms. Changes in EEG rhythms are characterized by considering the relative energy of EEG signal at each scale of decomposition. The analysis has been applied to EEG and EOG signals acquired on fifteen healthy subjects during polysomnography. In all the examined subjects, falling asleep is systematically accompanied by EEG energy redistribution among the different scales and by SEMs occurrence. In particular, SEMs anticipate EEG modifications, preceding alpha blocking and theta intrusion even by several (10-20) minutes. This result suggests that EOG activity may be used to monitor sleepiness and sleep onset and to predict decrease in behavioral performances associated with drowsiness.