Background: The pathogenesis of adolescent idiopathic scoliosis (AIS), including the role of brain and spinal inhibitory circuits, is still poorly elucidated. The aim of this study was to identify which central inhibitory mechanisms are involved in the pathogenesis of AIS.Design: A prospective neurophysiological study, using a battery of neurophysiological tests, such as cutaneous (CuSP) and cortical (CoSP) silent periods, motor evoked potentials (MEP) and paired-pulse transcranial magnetic stimulation (ppTMS).Settings: Neurophysiological laboratory.Participants: Sixteen patients with AIS (14 females, median age 14.4) and healthy controls.Outcome measures: MEPs were obtained after transcranial magnetic stimulation (TMS) and recorded from the abductor pollicis muscle (APB). ppTMS was obtained at interval ratios (ISI) of 1, 2, 3, 6, 10, 15 and 20 ms. The cortical silent period (CoSP) was recorded from the APB. The cutaneous silent period (CuSP) was measured after painful stimuli delivered to the thumb while the subjects maintained voluntary contraction of the intrinsic hand muscles. The data were analyzed and compared with those from healthy subjects.Results: The CoSP duration was significantly prolonged in AIS patients. A significantly higher amplitude of ppTMS for ISI was found in all AIS patients, without remarkable left-right side differences. No significant difference in MEP latency or amplitude nor in the CuSP duration was obtained.Conclusion: Our observation demonstrates evidence of central nervous system involvement in adolescent idiopathic scoliosis (AIS). Lower intracortical inhibition, higher motor cortex excitability, and preserved spinal inhibitory circuits are the main findings of this study. A possible explanation of these changes could be attributed to impaired sensorimotor integration predominantly at the cortical level.

Background and aims: Diverse neurologic symptoms in patients with COVID-19 have been reported. Encephalopathy usually develops in association with severe COVID-19. We present the case of a transient encephalopathy following mild respiratory symptoms of COVID-19. Methods: Case report. Results: 56-year-old male came to our attention because of headache and altered vision. His neurological examination on admission revealed visual anosognosia. Two weeks before the onset of neurological symptoms, he developed mild COVID-19 respiratory tract infection. His medical history included recently diagnosed type 2 diabetes mellitus on metformin and gliclazide treatment. An acute CT scan of the head was normal. A CT angiography showed stenosis of a right posterior cerebral artery. Antiplatelet therapy was started. The 2nd day after admission, the patient developed confusion and recurrent brief episodes of head and eye deviation to the left with impairment awareness. The 1st-line antiepileptic treatment with i.v. valproate was not fully effective. Some seizure control was achieved after adding benzodiazepines to his treatment. The 3rd day after admission, brain MRI revealed subtle subcortical ischemic changes in the right occipital lobe, stenosis of posterior cerebral artery, and T2 and FLAIR hyperintensities within the right hippocampus consistent with ongoing seizure activity. Over the next few days, antipsychotics were used to treat delirium. Recurring seizures were controlled after lacosamide was started. On the seventh day after admission, our patient was mildly confused but fully cooperative. His visual field testing field revealed no abnormality. Conclusion: Reversible encephalopathy can follow mild respiratory symptoms of COVID-19. (Figure Presented).

Evokované potenciály (EP) představují poměrně senzitivní, byť málo specifickou metodu v průkazu postižení jednotlivých drah centrálního nervového systému (CNS).Jsou stále indikovány u pacientů s roztroušenou sklerózou (RS) či při podezření na toto onemocnění, přestože je nelze uplatnit při průkazu diseminace v prostoru (DIS).Článek přináší přehled nejčastěji aplikovaných modalit EP (zrakové, somatosenzorické, motorické, kmenové akustické atd.) a jejich užití v diagnostice a monitorování průběhu RS s přihlédnutím k jejím formám.Somatosenzorické (SEP) a motorické (MEP) EP hodnotí funkci nejdelších drah, a proto jsou nej citlivějšími metodami v průkazu kondukční abnormity související s RS.Ukazují se také jako nejsilnější prediktory tíže budoucího postižení u pacientů s primárně progresivní RS.Role EP ustupuje v diagnostice RS do pozadí.Evokované potenciály se však jeví jako slibná metoda pro predikci průběhu onemocnění a monitoraci klinických studií s použitím nových léčiv. Klíčová slova:

Objectives: Traumatic lesions of brachial plexus are serious periferal nerve injuries. Neurological examination and CT myelography or MRI are the basic examination methods that can confi rm spinal root avulsion. To specify severity of the injury – electromyography and evoked potentials are used. The objective of this study was to determine whether implementation of cutaneous silent period that as seses function of small diameter A-delta fi bers, is useful as a dia gnostic tool in cervical root avulsion and brachial plexus injury. Material and methods: Clinical examination, imag ing studies (CT myelography or MRI) and neurophysiological examination were performed in 23 patients with traumatic brachial plexus injury (16 males, age 18–62 years). Needle EMG was obtained from muscles supplied by C5– T1 myotomes. CSP was recorded after painful stimuli were delivered to the thumb (C6 dermatome), middle (C7) and little (C8) fi ngers while subjects maintained voluntary contraction of intrinsic hand muscles. Results: Electrodia gnostic and CT/ MRI studies confi rmed brachial plexopathy involv ing mainly the upper trunk or cor respond ing C5, C6 roots in all patients. However, well defi ned CSP was still present in 16 subjects. CSP was absent in at least one of the dermatomes in the remaining seven patients. All these patients had severe plurisegmental sensitive lesion. Conclusion: CSP was still present, although not absolutely normal, in the majority of patients with severe brachial plexus injury. This suggests there are plurisegmental in nervations with residual function of A-delta fi bers and the presence of spinal inhibitory refl exes. Resistance of A-delta fi bers seems to be higher compared to motor fi bers despite of severe traumatic lesion. Autoři deklarují, že v souvislosti s předmětem studie nemají žádné komerční zájmy. The authors declare they have no potential confl icts of interest concerning drugs, products, or services used in the study. Redakční rada potvrzuje, že rukopis práce splnil ICMJE kritéria pro publikace zasílané do biomedicínských časopisů. The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers. P. Vaško1, A. A. Leis2, V. Boček1, L. Mencl3, P. Haninec 3, I. Štětkářová1 1 Neurologická klinika 3. LF UK a FN Královské Vinohrady, Praha 2 Methodist Rehabilitation Center, Jackson, Mississippi, USA 3 Neurochirurgická klinika 3. LF UK a FN Královské Vinohrady, Praha  prof. MUDr. Ivana Štětkářová, CSc. Neurologická klinika 3. LF UK a FN Královské Vinohrady Ruská 87 100 00 Praha e-mail: ivana.stetkarova@fnkv.cz Přijato k recenzi: 28. 4. 2015 Přijato do tisku: 7. 7. 2015

Chronický abúzus alkoholu postihuje kromě jiných orgánů také periferní nervový systém.Navzdory vysoké prevalenci mezi alkoholiky zůstává toto postižení často opomíjené.Postižení se týká všech typů nervových vláken včetně tenkých nemyelinizovaných vláken, která vedou bolest

OBJECTIVE: Lithium has been long used in psychiatry as an adjuvant treatment for bipolar disorder. Chronic lithium intoxication is very rare. DESIGN: We present the case of a 72-year-old female, treated with lithium for more than 10 years for bipolar disorder, who was admitted for gait impairment with weakness of limbs, myoclonus, speech impairment and memory disturbances. RESULTS: Diagnosis of lithium intoxication was based on clinical picture and determination of serum lithium levels. EEG showed severe encephalopathy with triphasic wave complexes. Sensory and motor axonal neuropathy was observed by EMG. Discontinuation of the drug leads to clinical improvement, although not to a fully neurological recovery. CONCLUSION: Lithium is still very effective drug, but requires regular monitoring of serum levels to prevent overdose and symptoms of intoxication. Neurophysiological methods, including EEG and EMG, are strongly recommended to determine the level of peripheral and/or central nervous system impairment.

Objective: Brachial plexus injuries are usually severe and involve the entire brachial plexus, sometimes occurring with root avulsions. Imaging and electrodiagnostic studies are an essential part of the lesion evaluation; however, the results sometimes show a discrepancy. The cutaneous silent period (SP) is a spinal inhibitory reflex mediated by small-diameter A-delta nociceptive fibers. The aim of the study was to determine if cutaneous SP testing may serve as a useful aid in evaluation of brachial plexus injury and/or in the diagnosis of root avulsion.Methods: In 19 patients with traumatic brachial plexus injury (15 males, age 18-62 years) we performed a clinical examination, CT myelography and neurophysiological testing. A needle EMG was obtained from muscles supplied by C5-T1 myotomes. Cutaneous SP was recorded after painful stimuli were delivered to the thumb (C6 dermatome), middle (C7) and little (C8) fingers while subjects maintained voluntary contraction of intrinsic hand muscles.Results: Electrodiagnostic and imaging studies confirmed root avulsion (partial or total) maximally involving C5, C6 roots in 12 patients, whereas only in 4 of them the cutaneous SP was partially absent. In the remaining subjects, the cutaneous SP was preserved.Conclusion: In brachial plexopathy even with plurisegmental root avulsion, the cutaneous SP was mostly preserved. This method cannot be recommended as a reliable test for diagnosis of single root avulsion; however, it can provide a quick physiological confirmation of functional afferent A-delta fibers through damaged roots and/or trunks. The clinicians may add this test to the diagnosis of spinal cord dysfunction.

Pallidal stimulation (GPi DBS) is an effective treatment of dystonic syndromes with a relatively high variability of clinical benefit. As patients with dystonia typically have a lower ability to suppress unwanted movements, we expected a decreased intracortical inhibition of motor cortex, which can be potentially reversed by GPi DBS. To distinguish between patients with dystonia according to the clinical outcome of GPi DBS using short-latency intracortical inhibition (SICI) of the motor cortex assessed by paired transcranial magnetic stimulation (TMS). We examined 22 patients (mean age 51 ± 17 years) with dystonia of various distribution and origin treated by GPi DBS in different time intervals from implantation. Paired TMS with subthreshold conditioning stimulus followed by a supratreshold testing stimulus 2.5 ms later were applied to the motor cortex to elicit SICI in GPi DBS ON and GPi DBS OFF condition two hours later. The clinical effect (CE) was expressed as a change in the dystonic score (Burke-Fahn-Marsden Dystonia rating Scale or Toronto Western Spasmodic Torticollis Scale) between actual GPi DBS ON condition and the preoperative state. The SICI was less effective in patients than in controls regardless of the ON and OFF conditions (p < 0.001) (Fig. 1aDownload : Download high-res image (206KB)Download : Download full-size image). Non-responders (n = 9; <25% CE) showed abnormally low SICI, partial responders (n = 5; 25%–50% CE) showed higher SICI and the highest SICI was in responders (n = 8; >50% CE, p < 0.05) (Fig. 1b). The MEP onset latency was shorter in patients in GPi DBS ON than in OFF condition (p < 0.001) (Download : Download high-res image (225KB)Download : Download full-size imageFig. 2a) and in addition, the shortest MEP onset latency was observed in non-responders (p < 0.001) (Fig. 2b). There was no correlation of the SICI or MEP onset latency with the position of the distal contact of the electrodes. Our results suggest that the best responders to GPi DBS treatment exhibited a similar level of SICI as in healthy controls. On the contrary, non-responders were unable to increase their reduced cortical inhibition and effectively suppressed dystonic symptoms. We speculate that decreased intracortical inhibition with abnormally fast transmission volley is underpinned by the poor complexity of the motor network. Supported by the grant IGA MZ ČR NT12282-5/2011.

Body image represents a multidimensional concept including body image evaluation and perception of body appearance. Disturbances of body image perception are considered to be one of the central aspects of anorexia nervosa and bulimia nervosa. There is growing evidence that body image distortion can be associated with changes in pain perception. The aim of our study was to examine the associations between body image perception, body dissatisfaction, and nociception in women with eating disorders and age-matched healthy control women. We measured body dissatisfaction and pain sensitivity in 61 patients with Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition diagnoses of eating disorders (31 anorexia nervosa and 30 bulimia nervosa) and in 30 healthy women. Thermal pain threshold latencies were evaluated using an analgesia meter and body image perception and body dissatisfaction were assessed using Anamorphic Micro software (digital pictures of their own body distorted into larger-body and thinner-body images). Patients with eating disorders overestimated their body size in comparison with healthy controls, but the two groups did not differ in body dissatisfaction. In anorexia and bulimia patient groups, body dissatisfaction (calculated in pixels as desired size/true image size) correlated with pain threshold latencies (r=0.55, p=0.001), while between body image perception (determined as estimation size/true image size) and pain threshold, no correlation was found. Thus, we demonstrated that in patients with eating disorders, pain perception is significantly associated with emotional contrary to sensory (visual) processing of one’s own body image. The more the patients desired to be thin, the more pain-sensitive they were. Our findings based on some shared mechanisms of body dissatisfaction and pain perception support the significance of negative emotions specific for eating disorders and contribute to better understanding of the psychosomatic characteristics of this spectrum of illnesses.

Background Deep brain stimulation (DBS) of the globus pallidus interna is an effective tool for the treatment of dystonia with possible distant effects reaching beyond the basal ganglia network. Aim We analyzed the cortical silent period (CoSP) to test inhibitory circuits at the cortical level, and the cutaneous silent period (CuSP) and the H-reflex to test inhibitory circuits at the spinal level. Methods The upper limb muscles of 16 patients (9F, aged 54 ± (SD)16 years) with generalized (N = 9) and cervical (N = 7) dystonia treated with DBS bilaterally were examined by the CoSP, CuSP and H-reflex in two states with random order: (i) in DBS ON and (ii) in DBS OFF condition two hours later, and compared with healthy controls. Results While the CuSP and H-Reflex did not differ between groups and remained unaffected by DBS, the CoSP was influenced significantly in dystonia. The CoSP onset latency was shortened (p < 0.05 corrected) and the CoSP duration prolonged (p < 0.01 corrected) in ON versus OFF condition. This effect was especially larger in generalized or phasic type of dystonia. Compared to healthy controls, the CoSP latency and duration became shorter in patients during the OFF condition only. Conclusion The pallidal DBS did not affect the spinal inhibitory circuitry in dystonia. However, the abnormally low cortical inhibition was normalized after DBS possibly offering more efficient suppression of aberrant dystonic movements.

Deep brain stimulation (DBS) of the globus pallidus interna (GPi) is widely used in treatment of pharmacoresistant dystonic syndromes. In our study, we analyzed functional connectivity change derived from resting state fMRI in two conditions: with the DBS chronically switched on (ON condition) and two hours after switching the DBS off (OFF condition). We used a graph theory utilizing the degree of centrality (DC) based on mapping links at the voxel level in each condition. We examined 21 patients (13 women, 8 men, aged 46 ± (SD)18 years) with dystonia of various origin (14 idiopathic, 2 DYT-1, 2 PKAN, 2 with parkinsonism, 1 post-anoxic) treated with GPi DBS bilaterally (10–102 months after implantation). The clinical state of patients with generalized dystonia (N = 13) was assessed by the Burke Fahn Marsden Dystonia Scale and patients with cervical dystonia (N = 8) were rated by the Toronto Western Spasmodic Torticollis Rating Scale one week before surgery and on the day of the fMRI session in the ON condition. Each subject was instructed to watch a cross while lying motionless in the supine position for 10 minutes during fMRI acquisition (1.5 T, T2*-weighted gradient-echo echo-planar imaging: FA/TR/TE = 90°/3000/51 ms, 200 repetitions). Group analysis of connectivity change was based on voxel-wise comparison between the DC maps in the ON and OFF conditions and on comparison with age-matched healthy subjects and displayed with FWE correction (P<0.05) at cluster level. In ON compared with OFF condition, a significant increase of DC was found in the thalamus bilaterally, in the right accumbens and subthalamus, in the upper and posterior brainstem and the left cerebellum (Fig. 1). Patients in OFF condition when compared to healthy controls showed lower DC in the thalamus and putamen bilaterally, in the mesial region involving SMA, pre-SMA, middle cingulate and precuneus, as well as in the left premotor cortex and parieto-occipital cortex bilaterally (Fig. 2). In the ON condition, DC was found to be lower than healthy controls only in the precuneus and left parietal cortex. Chronic GPi DBS in patients regardless of the type and etiology of dystonia caused an increase of resting state functional connectivity in the thalamus, subthalamic nucleus and brainstem, which are the key structures where the GPi directly or indirectly projects to. This observation is in agreement with the comparison of patients with healthy controls: in OFF condition, patients showed lower connectivity in the basal ganglia and motor network, while in the ON condition, functional connectivity in these regions became similar like in the healthy subjects. Supported by the projects IGA MZ ČR NT12282-5/2011 and PRVOUK P26/LF1/4.

The pathogenesis of idiopathic scoliosis (IS) remains poorly understood. Local changes in deep paraspinal muscles and/or dysfunction of spinal inhibitory circuits are not fully elucidated. We compared the morphological and functional changes of paraspinal muscles on both sides of the scoliosis curve. Before corrective surgery we performed EMG and muscle biopsy of paraspinal muscles at convexity and concavity of scoliotic curve in 10 subjects with IS (8 women, 11–29 years). Cutaneous silent period (CSP) induced by noxious digit II stimulation in thenar muscles was recorded in IS patients and in healthy volunteers. Right curve convexity had 8 subjects. All of them presented changes in muscle fiber distribution with numerical predominance of type I on the curve convexity. Seven subjects have increased MUP amplitude on this side (range 10–62%). CSP did not significantly differ between concavity and convexity but shortening of CSP duration was observed in more pronounced scoliotic curve. Our findings demonstrate a significant asymmetry in fiber type distribution corresponding with an altered function in paraspinal muscles with predominance on convexity of scoliotic curve. Spinal inhibitory reflex is preserved; however, it could be modulated in more progressive IS. Supported by Grants PRVOUK P34, IGA-NT 13693.

Stiff-person syndrome (SPS) is an autoimmune disease characterized by progressive rigidity and generalized muscle stiffness caused by loss of GABA-ergic inhibition. Diffuse impairment of the GABA-system can be observed by neurophysiological methods. We investigated intracortical and spinal inhibition and correlate these findings with clinical status. Fifty-one years old male with a two years history of stiffness and muscle spasms was investigated in our department. Subsequently, we performed EMG, paired TMS and cortical (CoSP) and spinal (CSP) silent periods. The patient had 50 times higher serum level of anti-GAD. He suffered from severe lumbar hyperlodosis, hypertrophy of axial muscles, and slightly asymmetrical generalized stiffness more pronounced on the left extremities. EMG discovered continuous involuntary muscle activity. Intracortical short-time inhibition (ICSI) after TMS stimulation was abnormal while stimulated both hemisphere and was more pronounced from the left APB muscle. CoSP and CSP were both abnormally shortened with more shortening when recorded from the left side. Our findings confirmed loss of GABA-ergic inhibition in SPS. Involvement of both GABA-A and GABA-B inhibitory circuit systems are present with makeable left-side asymmetry corresponding to clinical status.

The pathogenesis of adolescent idiopathic scoliosis (AIS) remains poorly understood. To date, potentially involved local changes in the deep paraspinal muscles still remain unknown.

The cutaneous silent period (CSP) is a spinal inhibitory reflex mediated by small-diameter A-delta fibers. Nociceptive impulses enter the spinal dorsal horn and suppress activity in spinal motor nuclei in neighboring myotomes. The aim of the study was to determine if CSP testing may serve as a useful aid in evaluation of brachial plexus injury involving root avulsion. In 19 patients with traumatic brachial plexus injury (15 males, age 18–62 years) we performed clinical examination, imaging studies (CT myelogram) and neurophysiologic testing. Needle EMG was obtained from muscles supplied by C5-T1 myotomes. CSP was recorded after painful stimuli were delivered to thumb (C6 dermatome), middle (C7) and little (C8) fingers while subjects maintained voluntary contraction of intrinsic hand muscles. Electrodiagnostic and imaging studies confirmed severe brachial plexopathy in most of patients. In 6 subjects with sensory disturbances, one of the CSP was absent. In the remaining 13 patients, a well defined CSPs were present. In brachial plexopathy with presumed avulsion, the CSP can provide quick physiologic confirmation of preserved or impaired conduction through damaged trunks and roots. In the cases of multiple sensory disturbances, the CSP is impaired or absent.

Objectives: Traumatic lesions of brachial plexus are serious periferal nerve injuries. Neurological examination and CT myelography or MRI are the basic examination methods that can confirm spinal root avulsion. To specify severity of the injury electromyography and evoked potentials are used. The objective of this study was to determine whether implementation of cutaneous silent period that asseses function of small diameter A-delta fibers, is useful as a diagnostic tool in cervical root avulsion and brachial plexus injury. Material and methods: Clinical examination, imaging studies (CT myelography or MRI) and neurophysiological examination were performed in 23 patients with traumatic brachial plexus injury (16 males, age 18-62 years). Needle EMG was obtained from muscles supplied by C5-T1 myotomes. CSP was recorded after painful stimuli were delivered to the thumb (C6 dermatome), middle (C7) and little (C8) fingers while subjects maintained voluntary contraction of intrinsic hand muscles. Results: Electrodiagnostic and CT/MRI studies confirmed brachial plexopathy involving mainly the upper trunk or corresponding C5, C6 roots in all patients. However, well defined CSP was still present in 16 subjects. CSP was absent in at least one of the dermatomes in the remaining seven patients. All these patients had severe plurisegmental sensitive lesion. Conclusion: CSP was still present, although not absolutely normal, in the majority of patients with severe brachial plexus injury. This suggests there are plurisegmental innervations with residual function of A-delta fibers and the presence of spinal inhibitory reflexes. Resistance of A-delta fibers seems to be higher compared to motor fibers despite of severe traumatic lesion.