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This prospective study was designed to assess whether patients with skeletal deformities show characteristic masseter inhibitory reflex (MIR) and blink reflex (BR) patterns. A secondary aim was to investigate whether these reflexes change following bilateral sagittal split osteotomy (BSSO).Fourteen consecutive patients who underwent single-jaw BSSO and 14 class I subjects who constituted the control group were enrolled into the study. MIR and BR, obtained by the stimulation of supraorbital (SBR) and mental nerves (MBR), were electrophysiologically recorded. Sensory impairment in the mental nerve distribution was clinically tested. Three evaluation periods were specified as immediately before (T0), 1 month (T1) and 6 months (T2) after surgery.MIR early silent period duration was significantly shorter in the patients at T0 (p 0.001). Sensory deficits developed on 23 sides after BSSO, of which, 17 recovered after 6 months. At T1, MBR was inelicitable bilaterally in 3 patients and unilaterally in 2 patients. These responses were still unrecordable bilaterally in 1 patient, and unilaterally in 4 patients at T2. MIR were unrecordable on 18 sides at T1 and recovered on 11 sides at T2. There were no parallels between the clinical sensory deficits and the abnormal results of the reflexes.Shorter MIR in patients with dentofacial abnormalities may be a reflection of an adapted trigeminal reflex mechanism. Although MBR and MIR abnormalities do not develop parallel to the clinical sensory deficits, their course might provide insights into the disturbed trigeminal reflex pathways.ZIELSETZUNGEN: In dieser prospektiven Studie sollte untersucht werden, ob Patienten mit Skelettdeformitäten charakteristische Muster des inhibitorischen Masseterreflexes (MIR) und des Blinzelreflexes (BR) aufweisen. Ein weiteres Ziel war es, zu untersuchen, ob sich diese Reflexe nach einer bilateralen sagittalen Spaltosteotomie (BSSO) verändern.Vierzehn konsekutiv aufgenommene Patienten, die sich einer monomaxillären BSSO unterzogen hatten, und 14 Klasse-I-Patienten, welche die Kontrollgruppe bildeten, wurden in die Studie aufgenommen. Der MIR sowie durch Stimulation des N. supraorbitalis (SBR) und des N. mentalis (MBR) getriggerte BR wurden elektrophysiologisch aufgezeichnet. Die sensorischen Beeinträchtigungen im Bereich des N. mentalis wurden klinisch untersucht. Drei Bewertungszeiträume wurden festgelegt: unmittelbar vor (T0), 1 Monat (T1) und 6 Monate (T2) nach der Operation.Die Dauer der frühen, silenten Phase des MIR war bei den Patienten bei T0 signifikant kürzer (p 0,001). Nach der BSSO entwickelten sich auf 23 Seiten sensorische Defizite, von denen sich 17 nach 6 Monaten erholten. Zum Zeitpunkt T1 war der MBR bei 3 Patienten beidseitig und bei 2 Patienten einseitig nicht auslösbar. Bei T2 waren diese Reaktionen bei einem Patienten bilateral und bei 4 Patienten unilateral nicht mehr nachzuweisen. Der MIR war bei T1 auf 18 Seiten nicht nachweisbar und bei T2 auf 11 Seiten wieder vorhanden. Es gab keine Parallelen zwischen den klinischen sensorischen Defiziten und den abnormalen Ergebnissen der Reflexe.Ein kürzerer MIR bei Patienten mit dentofazialen Anomalien kann Ausdruck eines angepassten Trigeminusreflexmechanismus sein. Auch wenn sich die MBR- und MIR-Anomalien nicht parallel zu den klinischen sensorischen Defiziten entwickeln, könnte ihr Verlauf Aufschluss über die gestörten trigeminalen Reflexbahnen geben.

Objective: Cutaneous allodynia (CA) is a common symptom in migraine. Its incidence is more frequent in the chronic migraine (CM). CA usually occurs during pain attacks. However, it can also be interictal and its frequency and severity seem to be correlated with the duration of the disease. Several quantitative sensory testing (QST) studies have revealed variable results about mechanical and thermal allodynia accompanying migraine. This study aimed to investigate the effects of CA and onabotulinumtoxinA (BoNT-A) injection on the thermal thresholds measured by QST in patients with CM. The effects of BoNT-A on headaches, CA, and other accompanying symptoms of migraine were also evaluated. Methods: Single BoNT-A injections were performed in 22 female cases (mean age: 38.1 +/- 7.2 years) with CM. Patients were evaluated at 1-7 days before, 28-35, and 84-91 days after the injection. The 22 healthy women in the control group (mean age: 36.6 +/- 7.6 years) were examined once. Headache and its characteristics, medication intake, allodynia, presence of anxiety, and depression symptoms were evaluated through relevant scales. The heat (HDT) and cold (CDT) detection thresholds on the forehead and hand were measured bilaterally with QST. The presence of brush allodynia for patients was examined by applying a 4 x 4 gauze pad over the same areas.Results: The patients in the CM group had migraine for an average of 22.5 +/- 6.1 years and CM for 6.1 +/- 3.2 years. The average number of painful days per month was 22.1 +/- 4.0 days. All the patients had migraine attacks with CA (mean 5.6/month). The average allodynia symptom checklist (ASC-12) score was 7.8 +/- 6.2. Thermal thresholds measured in the patients with CM were similar to those of the controls. Thermal thresholds did not show significant differences between the symptomatic and the asymptomatic sides at the last migraine attack. There was also no correlation between the allodynia revealed by the physical examination and the thermal thresholds detected by QST. The ASC-12 score decreased significantly with BoNT-A injection (p = 0.030), but no significant change was observed in thermal thresholds after this treatment. Conclusion: There was no significant correlation between CA and thermal thresholds. BoNT-A was successful in relieving headache and other associated symptoms, including CA, but had no significant effect on QST parameters.

BACKGROUND Compound muscle action potential (CMAP) scan and MScanFit have been used to understand the consequences of denervation and reinnervation. This study aimed to monitor these parameters during Wallerian degeneration (WD) after acute nerve transections (ANT). METHODS Beginning after urgent surgery, CMAP scans were recorded at 1-2 day intervals in 12 patients with ANT of the ulnar or median nerves, by stimulating the distal stump (DS). Stimulus intensities (SI), steps, returners, and MScanFit were calculated. Studies were grouped according to the examination time after ANT. Results were compared with those of 27 controls. RESULTS CMAP amplitudes and MScanFit progressively declined, revealing a positive correlation with one another. SIs were higher in WD groups than controls. Steps appeared or disappeared in follow-up scans. The late WD group had higher returner% than the early WD and control groups. CONCLUSIONS MScanFit can monitor neuromuscular dysfunction during WD. SIs revealed excitability changes in DS.

Objective To extract insight about the mechanism of repeater F-waves (Frep) by exploring their correlation with electrophysiologic markers of upper and lower motor neuron dysfunction in amyotrophic lateral sclerosis (ALS). Methods The correlations of Frep parameters with clinical scores and the results of neurophysiological index (NI), MScanfit MUNE, F/M amplitude ratio (F/M%), single and paired-pulse transcranial magnetic stimulation (TMS), and triple stimulation technique (TST) studies, recorded from abductor digiti minimi (ADM) and abductor pollicis brevis (APB) muscles of 35 patients with ALS were investigated. Results Frep parameters were correlated with NI and MScanfit MUNE in ADM muscle and F/M% in both muscles. None of the Frep parameters were correlated with clinical scores or TST and TMS measures. While the CMAP amplitudes were similar in the two recording muscles, there was a more pronounced decrease of F-wave persistence in APB, probably heralding the subsequent split hand phenomenon. Conclusion Our findings suggest that the presence and density of Freps are primarily related to the degree of lower motor neuron loss and show no correlation with any of the relatively extensive set of parameters for upper motor neuron dysfunction. Significance Freps are primarily related to lower motor neuron loss in ALS.

Motor unit number estimation by F waves (F-MUNE) is an uncommonly used MUNE technique. Our aim in this study was to assess the sensitivity of F-MUNE values elicited with newly developed software in motor neuron diseases.F waves were recorded by 300 submaximal stimuli from abductor digiti minimi and abductor pollicis brevis muscles of 35 patients with amyotrophic lateral sclerosis, 18 with previous poliomyelitis, and 20 controls. The software determined the surface motor unit action potentials (sMUAPs) and calculated the F-MUNE values. Compound muscle action potential scans were also recorded to obtain MScanFit.The sMUAP amplitudes were higher and F-MUNE values were lower in both muscles of the patients when compared with controls. F-MUNE values could distinguish patients from controls. Significant correlations were found between F-MUNE and MScanFit in the patient groups.The new F-MUNE software offered promising results in revealing motor unit loss caused by motor neuron diseases.

The aim of this study was electromyographic description of changes in swallowing before and after bilateral sagittal split ramus osteotomy. In this prospective study, twenty-eight patients were divided into 3 groups according to the occlusion pattern: Group I (Angle Class III), Group II (Angle Class II), and Control (Class I). Serial cone-beam computed tomography analyses and electromyographic data were collected preoperatively, 1st and 6th months after setback surgery in Group I, and advancement surgery in Group II. Swallowing reflex with 3-20 ml water bolus were studied. Patients were further divided into two subgroups according to the magnitude of relapse. The mean setback of the mandible was 4.62 +/- 1.92 mm in Group I, and the mean advancement was 4.19 +/- 2.00 mm in Group II. Mandibular relapse rate was 17.40%. Oral preparation phase shortened after surgery in both study groups. Two subjects in Group II and one in Group I had piecemeal deglutition, and two of them became normal postoperatively. Most of the swallowing durations of the relapsed cases were longer than those of stabilized patients. Important clinical considerations are as follows: the oral preparation period becomes shorter after surgery; piecemeal deglutition may disappear after treatment; and individuals with a longer oral period and piecemeal deglutition may have increased tendency to skeletal relapse. This multidisciplinary study enhances our understanding of the adaptive response to the swallowing reflex after orthognathic surgery and provides novel insight into the association between the submental muscle activity and relapse in orthognathic patients.

Purpose To examine upper motor neuron functions comparatively in patients with amyotrophic lateral sclerosis (ALS) and poliomyelitis survivors using transcranial magnetic stimulation (TMS) methods. Methods Single- and paired-pulse TMS with conventional methods and the triple-stimulation technique were performed by recording from the abductor digiti minimi and abductor pollicis brevis muscles in 31 patients with ALS, 18 patients with poliomyelitis survivors, and 21 controls. Nine patients were diagnosed as having postpoliomyelitis syndrome after a 6-month follow-up. Results Triple-stimulation technique and some of conventional TMS studies were able to distinguish ALS from both poliomyelitis survivors and controls. A reduced ipsilateral silent period in abductor pollicis brevis muscles was the only parameter to show a significant difference when comparing thenar and hypothenar muscles in ALS. No significant difference was present in any TMS parameters between the postpoliomyelitis syndrome and non-postpoliomyelitis syndrome groups. Conclusions Conventional TMS and particularly triple-stimulation technique studies are helpful in disclosing upper motor neuron dysfunction in ALS. The results of this study might favor the cortical hypothesis for split hand in ALS, but they revealed no significant indication for upper motor neuron dysfunction in postpoliomyelitis syndrome.

Background Diagnostic evaluation of patients with parenchymal Neuro-Behcet's disease (NBD) requires magnetic resonance imaging (MRI), neuro-ophthalmologic, and neuropsychological evaluation. In this study, we aimed to find out the ideal diagnostic method that most closely reflects the progress in cognitive disability and brain atrophy in NBD. Methods In this matched case-control study, we included patients with parenchymal NBD, Behcet's disease without neurological involvement (BD), rheumatoid arthritis, and healthy controls. Detailed ophthalmological examination, pattern-reversal visual evoked potentials (prVEP) test, optical coherence tomography (OCT), brain MRI volumetry and cognitive evaluation tests were performed. Disability status was assessed by revised EDSS. Results Sixty-eight individuals (35 female, 33 male) were recruited. Mean ACE-R scores were significantly lower in the NBD group (NBD vs. healthy, 80±14.4, 93±4.9, p=0.002). prVEP values were similar across groups, but retinal nerve fiber layer thickness (RNFLT) were more frequently abnormal in the NBD group. We found considerable volume reduction in the brainstem, cerebellum, hippocampus, and thalamus in the NBD group. Regarding prVEP, 120 minutes P100 amplitude (p

Compound Muscle Action Potential (CMAP) Scan used in the diagnosis and in the monitoring of Neuromuscular Diseases is based on recording the responses obtained from the gradual stimulation of a peripheral nerve. Clearly visible differences between CMAPs are referred as step. The maximum CMAP percentage of all detected steps are defined as Step Percentage and this is one of the parameters providing evidence for Motor Unit (MU) loss and for reinnervation. The aim of this study is to develop an algorithm which enables to estimate the step percentage more quantitatively. Motor neuron groups which were created through a simulator software were stimulated gradually. The step sizes were computed by utilizing the obtained responses as CMAPs in computing step sizes. Then, these step sizes were sorted in descending order. The step percentage was estimated by taking the cumulative sum of the values greater than two standard deviations (SD) of these sorted step sizes by running the aforementioned algorithm. It was seen that there are larger in fluctuations Step% values in motor neuron groups with lower number of axons, however, a more regular decreasing trend with smaller fluctuations was observed in higher number of axons. In the future studies, the inclusion of further motor neurons with greater axons numbers will be established. Moreover, the application of the algorithm for the patient data will be also considered. © 2019 IEEE.

Introduction Autosomal dominant cortical tremor, myoclonus, and epilepsy (ADCME) syndrome is a genetically heterogeneous and under-recognized disease characterized by tremulous movements mimicking essential tremor, myoclonus, and rare generalized tonic-clonic seizures. Here we described the clinical and electrophysiological features of three siblings with ADCME syndrome mimicking juvenile myoclonic epilepsy (JME). Methods Three siblings (two females and one male) diagnosed with ADCME were analyzed by electroencephalogram (EEG), somatosensory evoked potentials, and accelerometric recordings. The results were compared with 14 JME patients without tremor and 14 with essential tremor (ET). Results The shared features of the siblings were cortical tremor, myoclonia, epilepsy, migraine, and psychiatric symptoms. In all siblings, tremor had started before myoclonic epilepsy associated with 4-6 Hz generalized spike and wave discharges. The N20-P25 and P25-N35 amplitudes were substantially higher in the three siblings with ADCME. Although tremor frequencies were similar to those of the ET group, the siblings had mild interrupting low-amplitude myoclonus, suggestive of cortical tremor, in the accelerometric analysis. Conclusion We presented a detailed clinical evaluation with electrophysiological confirmation of ADCME syndrome in a Turkish family. This rare clinical picture might be misdiagnosed as JME and should be kept in mind to ensure correct diagnosis and to provide a homogenous group for genetic studies.

INTRODUCTION The aim of this study was to re-evaluate jitter values of healthy subjects in whom pairs of single-fiber-like potentials were recorded from voluntary activated periocular muscles using a disposable 37-mm concentric needle electrode (CNE) with 2-kHz low-cut filtering. METHODS We reviewed the recordings of 129 subjects (85 women; 44 men; mean age, 43.8±15.3 years). The m. frontalis group included 116 subjects, and the m. orbicularis oculi group included 18 subjects. Jitter values were expressed as the mean consecutive difference (MCD) of 20 different pairs. RESULTS The mean MCD (n=2680) was 22.5±9.7 μs (range, 5-121 μs), and the upper 95% confidence limit (CL) was 39 μs. The mean of 134 MCD values for each subject was 22.5±3.7 μs (range, 15-33 μs), and the upper 95% CL was 30 μs. The outer limit of the 18th highest MCD values out of 20 recordings for each subject was 31.3±6.5 μs (range, 18-53 μs), with an upper 95% CL of 43.3 μs. CONCLUSION Using a conventional 37-mm CNE with 2-kHz low-cut filtering may be a cost effective alternative to a single-fiber electrode in periocular muscles if strict criteria are used for acceptable signals. Jitter values of >44 μs that were calculated from single-fiber-like action potential pairs should alert the physician regarding the possibility of neuromuscular junction disorders and constitute an indication for a further diagnostic investigation.

The brain-derived neurotrophic factor (BDNF) gene Val66Met polymorphism may cause impairment in short-term motor learning by reducing activity-dependent BDNF expression, which causes alterations in synaptic plasticity by changing glutamatergic and GABAergic synaptic transmissions. Sensory-motor integration (SMI) plays an important role in motor learning. In this study, we investigated the role of this polymorphism on SMI during a complex motor learning practice. Forty-three healthy participants performed standardized 5-day basketball shooting exercises under supervision. Electrophysiologic SMI studies were performed before the first day exercise (T0) and after the first and fifth day exercises (T1 and T2, respectively). SMI was studied using electrical median nerve stimulation at the wrist, followed by transcranial magnetic stimulation (TMS) of the contralateral motor cortex with various inter-stimulus intervals (ISIs). Recordings were made from the thenar and forearm flexor muscles. Participants were divided into two groups according to their BDNF genotype. Group 1 consisted of 26 subjects with the Val66Val genotype and group 2 included 17 subjects with the BDNF Met allele. Group 2 had a lower increase in basketball scores at day 5. Moreover, they had higher afferent facilitation for the responses recorded from both thenar and forearm flexor muscles at T1, but these changes could not be maintained until T2. This non-persistent early hyper-responsivity of the sensory-motor cortex in subjects with the BDNF Met allele might be explained by a transient upsurge of cortical excitability to compensate the insufficient cortical plasticity during motor learning, which could be considered as a sign of lower performance in motor skill learning.

nofulltext# --- Artuğ, Tuğrul (Arel Author), In this study, motor response recordings were acquired from thenar and hypothenar muscles of poliomyelitis survivors, ALS patients and healthy participants by using CMAP Scan method. CMAP Scan curve was plotted by using 500 stimuli between minimum and maximum stimulus intensity. Automatic analysis software was developed with MATLAB for calculating CMAP Scan parameters. Statistical results revealed that step%, D50 and returner% values can differentiate healthy individuals from the patients. The developed software helps clinicians for following up the progression rate of the diseases which cause anterior horn cell degeneration.

To compare blink reflex examination findings in patients with idiopathic intracranial hypertension (IIH) with migraineurs and controls and to investigate the role of blink reflex data in the follow-up by evaluating their relationship with clinical symptoms.We included 23 patients with IIH, 15 migraineurs, and 16 controls. Blink reflex was studied with bilateral paired stimulations, and the 2R2/1R2 and 2R2c/1R2c area ratios, 1R2, 2R2, 1R2c, and 2R2c latencies were compared (R2:ipsilateral R2 response, R2c:contralateral R2 response).2R2/1R2 area ratios at 200, 300, and 500 ms interstimulus intervals were significantly higher in the IIH group compared with the controls, and significantly higher 2R2/1R2 area ratio at 200 ms interstimulus interval was also detected in the IIH group compared with the migraine group. Significantly shorter 2R2 latencies were found at 500 and 800 ms interstimulus intervals in IIH group compared with the migraine group and controls. Significantly higher 2R2/1R2 area ratios at 500, 800 ms, and 2R2c/1R2c area ratios at 300, 500, and 800 ms were detected in patients with IIH in remission compared with patients with attacks.The significant increase in R2 recovery rates in patients with IIH in remission suggests that there is an increased excitability in the trigeminal pathways. Our findings may provide a new perspective for IIH mechanism related to trigeminal hyperexcitability and evaluating new management strategies.

Background Poliomyelitis survivors (PS) become candidates to post-polio syndrome (PPS) in their later lives. The mechanism of PPS has been suggested to be multifactorial involving cortical, spinal and peripheral mechanisThe aim of this study was to evaluate TMS parameters in PS and to compare them with those of amyotrophic lateral sclerosis (ALS) patients and controls. Material and methods Single and paired TMS, contralateral and ipsilateral silent period (SP) and triple stimulation technique (TST) were performed by recording from abductor digiti minimi (ADM) and abductor pollicis brevis (APB) muscles of 18 PS, 31 ALS patients and 21 controls. The results were compared with mixed ANOVA and nonparametric independent tests. Results No significant difference was present for within and between subject factors except those for the different interstimuli intervals. Resting motor threshold and MEP/M% in ADM, MEP amplitudes and latencies and TST% in both ADM and APB were significantly different. In posthoc analyses, MEP latencies were higher and TST% were lower in both ADM and APB in ALS group (20.7 ± 4.2 ms, 22.4 ± 5.0 ms, 83.1 ± 42.2, 72.3 ± 29.9) as compared to PS (18.3 ± 1.0 ms, 19.2 ± 2.0 ms, 101.6 ± 15.9, 98.1 ± 14.9), MEP/M% in ADM were lower in PS group (56.0 ± 13.4) as compared to controls (85.2 ± 23.9). SPs, TST, MEP amplitudes and latencies and MEP/M amplitudes did not show any significant difference between ADM and APB in both patient groups. Conclusions Our results revealed upper motor neuron dysfunction in ALS compared to PS and may provide limited evidence about presence of an abnormal cortical drive to mostly uninvolved upper extremity muscles in PS.

Background This study aimed to explore the subtle motor unit(MU) changes in asymptomatic muscles of poliomyelitis survivors (PS) using CMAP Scan analysis. Material and method Nineteen PS cases and 21 controls were recruited. CMAP Scan recordings were obtained from asymptomatic thenar and hypothenar muscles. CMAP Scan parameters indicating nerve excitability [stimulus intensities producing 50%, 95% and 5% of the CMAP amplitude (SI%5, SI%50, SI%95), absolute range width (ARW) (SI%95-SI%5), relative width (RW) (SI95 − SI5)/SI5], all step parameters and D50 which reflect the MU motor unit loss and reinnervation were analyzed. The new motor unit number estimation (MUNE) method, MscanFit was also calculated. Results There were no significant differences in ages, maximum CMAP amplitudes and MScanFit MUNE between the groups. PS group median and ulnar D50 values (46.76 ± 10.98, 46.19 ± 12.42 respectively) were lower than control group (37.21 ± 17.37, 36.44 ± 11.99) (p Conclusions CMAP Scan can show reduced axonal excitability and reveal insidious MU loss and reinnervation in presumably unaffected muscles of PS, regardless of the decrease in CMAP amplitudes or a significant reduction in MUNE values.

WOS: 000404296300015 PubMed ID: 28680318 Introduction: Cramp-fasciculation syndrome (CFS) is a rare peripheral nerve hyperexcitability syndrome. There are only a few reports on clinical and serological profile of a CFS cohort that was followed up by a single outpatient clinic. Methods: Clinical, electrophysiological, and serological features of 6 CFS patients (5 men, 1 woman; 27-65 years old) were investigated. Results: All patients presented with cramps, fasciculations, muscle pain, and autonomic symptoms, and 2 also reported numbness and burning sensation in limbs, suggestive of neuropathic pain. Antibodies to uncharacterized voltage-gated potassium channel (VGKC)-complex proteins were found in 2 patients and to contactin-associated protein-like 2 (CASPR2) in 1 patient. None of the patients had a tumor. Most of the patients revealed prolonged after-discharges following tibial nerve stimulation. Nerve conduction studies and R-R interval variability tests were normal, whereas sympathetic skin responses were increased in amplitude in 3 seronegative patients. Five patients showed favorable response to carbamazepine or pregabalin treatment, whereas 1 VGKC-antibody- positive patient was resistant to carbamazepine and immunosuppressant treatment. Conclusion: Neuropathic pain and VGKC-complex antibodies may be encountered in CFS patients. Although autonomic symptoms are commonly found in CFS, routine autonomic system tests which are done in electrophysiology laboratories might yield normal results. Amaç: Kramp-fasikülasyon sendromu (KFS) nadir görülen bir periferik sinir hipereksitabilite sendromudur. Tek bir merkezden takip edilen KFS hastalarının klinik ve serolojik özelliklerinin bildirildiği az sayıda yazı vardır. Yöntem: Altı KFS (5 erkek/1 kadın, yaş aralığı: 27-65 yıl) hastasının klinik, elektrofizyolojik ve serolojik özellikleri incelendi. Bulgular: Bütün hastalarda kramp, fasikülasyon, kas ağrısı ve otonom belirtiler görülürken ikisinde ayrıca nöropatik ağrıyı düşündüren ekstremitelerde uyuşma ve yanma hissi mevcuttu. İki hastada tanımlanmamış voltaja duyarlı potasyum kanalı kompleks proteinlerine [voltage-gated potassium channel (VGKC)-complex proteins] karşı oluşmuş antikorlar, bir hastada “contactin-associated protein-like 2 (CASPR2)” antikoru bulundu. Hastaların hiçbirinde tümör yoktu. Tibial sinir stimülasyonu sonucunda hastaların çoğunda uzamış ard boşalımlar görüldü. Sinir iletim çalışmaları ve R-R interval değişkenliği testleri normalken seronegatif olan 3 hastada sempatik deri yanıtı amplitüdleri artmıştı. Beş hasta karbamazepin ve pregabalin tedavisine iyi cevap verirken VGKC-antikoru pozitif olan bir hasta karbamazepin veya immünsüpresyon tedavisine dirençli idi. Sonuç: Nöropatik ağrı ve VGKC-kompleks antikor birlikteliği KFS hastalarında görülebilir. Otonom belirtiler KFS’li hastalarda sık bulunmasına rağmen elektrofizyoloji laboratuvarlarında uygulanan rutin otonom sistem test sonuçları normal kalabilir.

Summary Aim of the study In two previous studies, we found that the compound muscle action potential (CMAP) amplitude loss was significantly higher than the loss of estimated motor unit numbers in the course of Wallerian degeneration (WD). In order to overcome some drawbacks of the method previously used, we performed a similar CMAP vs MUNE comparison by using the statistical motor unit number estimation (MUNE) method. Patients and methods Initial electrophysiological studies on 6 patients were performed between 22 and 98 hours after the injuries; it was possible to make repeated examinations, four times in 1 nerve, twice in 1 nerve and three times in 4 nerves, before the eventual complete disappearance of the CMAPs. Results The transected/intact (T/I) side CMAP ratios declined steeply as WD evolved. They were significantly lower than the relatively stable MUNE ratios 48 hours after the injury. Conclusion This study, performed with the use of statistical MUNE, strengthens our previous observation by the incremental method that might have some relevance to the pathophysiology of early WD. CMAP amplitude loss that is more than expected from the amount of axonal degeneration may indicate a considerable amount of inactive muscle fibers in the motor units innervated by the nerve fibers, which are undergoing degeneration but still retain their excitability. Although technical sources of error cannot be totally excluded, our findings could more likely be explained by the failing of neuromuscular synapses in an asynchronous order before complete unresponsiveness of the motor unit ensues.

Introduction The aim of this study was to analyse MScanFit MUNE, D50 and step% values elicited from the CMAP scan curves of thenar and hypothenar muscles in patients with amyotrophic lateral sclerosis (ALS) and healthy controls. Methods Thirty-four ALS patients (31 definite, 1 probable and 2 possible, according to Awaji criteria) and 24 healthy controls were included. CMAP scan curves were recorded from both thenar and hypothenar muscles by applying 500 stimuli. Step% and D50 values were calculated semi-automatically and MScanFit MUNE was calculated by using the freeware version of Qtrac software. Results Mean MScanFit MUNE and D50 values were lower and step% values were higher significantly in patients (48.8, 25.0, 32.5 in thenar muscles and 66.5, 28.9, 17.0 in hypothenar muscles, respectively) as compared to healthy controls (112.5, 45.6, 4.0 in thenar muscles and 124.5, 46.6, 1.1 in hypothenar muscles; p p Conclusion Step% and MScanFit MUNE are parameters correlated with each other and they are sensitive tools in revealing the severities and the courses of the electrophysiological abnormalities in ALS.

Background Wallerian degeneration (WD) includes complex physiological changes in the distal portion of the axon which follow a severe injury. The aim of this study was to advance our earlier observations with MUNE studies during early stages of WD by evaluating the CMAP Scan curve and MScanFit MUNE in the same period. Materials and methods Twelve patients with acute nerve transections at the forearm (7 median, 5 ulnar) were recruited. First electrophysiological studies, performed at 9–72 h after the insult, were followed by serial studies at 1–2 day intervals until CMAP amplitudes reached at zero. At each session, CMAP Scan curves were recorded, their quantitative parameters and the new MUNE method, MScanFit, were calculated. The results were grouped according to the recording time after injury (before and after the 48th hour). They were compared with those of healthy controls and amyotrophic lateral sclerosis (ALS) patients. Results Excitability of axons was reduced in patients with transected nerves, as compared controls and ALS patients, irrespective of the recording time. In most of the patients, MUNE values decreased during the follow-up as a result of relatively more pronounced reduction of CMAP amplitudes as compared to mean unit sizes. While steps occurred in 8 patients, D50 remained unchanged during the follow-up. Conclusions These suggest higher ability of MScanFit, as compared to other MUNE methods, in discriminating the changes caused by functional instability of neuromuscular junction. Occasional steps in the early WD deserve some arguments on their possible mechanisms.

Purpose We aimed to investigate juvenile myoclonic epilepsy (JME) patients complaining of tremor unrelated to valproate (VPA) treatment and evaluate if there were differences between JME patients with and without tremor and essential tremor (ET) patients to exclude comorbidity. Methods Fifteen JME cases with the complaint of tremor, 14 JME patients without tremor, 14 patients with ET and 14 healthy subjects (HS) were included. Regularity, frequency and amplitude of the tremor and superimposed myoclonia were assessed by accelerometric analysis. Cortical SEPs evoked by the stimulation of the median nerve were recorded bilaterally. Clinical and neurophysiologic features were statistically compared between the groups. Findings Amplitude of postural tremor of the left hand was significantly increased in the ET group compared to JME patients with tremor, but there were no differences regarding to frequency. Strikingly, there were superimposed irregular, low-amplitude inconstant myoclonic jerks located to distal part of the fingers in JME group with tremor. Initial frequency of myoclonic seizures was also significantly higher in this group compared to JME patients without tremor but this difference disappeared after treatment. The group of JME with tremor had the highest N20-P25 and P25-N35 amplitudes, followed by JME without tremor, ET and HS, respectively. Conclusion Tremulous hand movements in JME resembled ET, but their amplitude was lower and characterized with accompanying irregular myoclonic jerks. The presence of tremor in JME patients should be taken into consideration to create more homogeneous groups in genetic and pathophysiological studies of JME.

Eyelid myoclonia (EM) with or without absences are a rare type of generalized seizures associated with a variety of epilepsy syndromes with an unknown pathophysiology. The aim of this study was to investigate the possible contribution of the brainstem structures in this underrecognized special type of seizures. Sixteen consecutive patients with EM, diagnosed with genetic generalized epilepsy (GGE) according to International League Against Epilepsy 2010 criteria were included. Brainstem excitabilities were examined by blink reflex (BR) studies. The results of BR studies in GGE patients with EM were statistically compared with 2 control groups; namely age- and gender-matched healthy volunteers and juvenile myoclonic epilepsy (JME) patients without any absences and using similar antiepileptic drugs. There were no statistical differences between the thresholds of the BR studies and the BR recovery curves in terms of amplitudes and areas of healthy subjects, JME patients and GGE patients with EM. Our findings do not support a profound interictal hyperexcitability in the BR-related brainstem structures of the GGE patients with EM. It can be considered that EM may be associated with excitability changes of the occipital cortex and other cortical areas.

Objectives: To study motor unit number estimation (MUNE) in acutely transected peripheral nerves, and to retest our previous observation which had revealed a discordance between the loss of compound muscle action potential (CMAP) size and decrease in MUNE during Wallerian degeneration. Methods: In eight patients with nine transected median or ulnar nerves, a total of 18 electrophysiological studies were performed before the complete nerve degeneration ensues. CMAP recordings and incremental MUNE studies were performed by stimulation of the nerves at the wrist level and recording from the appropriate hand muscles. The same studies repeated on the contralateral side. Results: Injury side to intact side ratios of the MUNEs were significantly higher than the CMAP ratios. Mean step areas in MUNE studies were found to be lower on the transected sides after 72 hours post-injury. Discussion: These findings support the existence of an electrophysiologically observable asynchrony in neuromuscular synapse d...

Introduction The aim of this study is to compare repeater F-wave parameters with CMAP amplitudes recorded from the hand muscles (as indicators of the amount of lower motor neuron [LMN] loss) and with the triple stimulation technique (TST) ratios in the same muscles (as indicators of upper motor neuron [UMN] involvement) in 19 patients with amyotrophic lateral sclerosis (ALS). Methods Ninety F-waves were recorded from thenar and hypothenar muscles by supramaximal stimuli applied to the relevant nerves at the wrist level. Repeater F-waves (Frep) were visually defined as those presented with the same amplitude, latency and shapes. Repeater neuron (RN) index, Frep index, persistances of F-waves, F/M amplitude ratio and the neurophysiologic index (NI) were calculated. By depending our laboratory normals, TST ratio values lower than 82% and 86% were accepted as abnormal showing UMN involvement in thenar and hypothenar muscles respectively. Results TST ratios were abnormal in 13 thenar and 11 hypothenar muscles. None of the Frep parameters showed any significant relationship with the abnormal TST ratios, except the lower Frep index in thenar muscles, in patients with UMN involvement according to low TST ratios. However, there was a strong negative correlation with the CMAP amplitudes and Frep index and RN index values in hypothenar muscle (Spearman’s rho, p Conclusion These findings imply that repeater F waves might be a manifestation of LMN loss more than being a result of UMN involvement.

Introduction Post-polio muscular atrophy (PPMA) is characterized by new onset or increased weakness in patients with prior poliomyelitis after a stable period of time. Loss of highly reinnervated motor units during ageing has been accused for the development of this syndrome which is also known as “unstable-polio”. These patients have less number of motor units that can be estimated by conventional electrophysiological methods. By showing the large steps, CMAP scan provides information about the amount of collateral reinnervation in the construction of total muscle response (CMAP). As well as the number of motor units, their territory is also an object of curiosity. It is possible to record bioelectrical activity of motor unit lengthwise by scanning EMG and depict the temporal and spatial features of motor unit action potential (MUAP). This presentation aims to combine the findings in CMAP scan with scanning EMG and draw attention to reinnervation status of 2 PPMA patients whose tibialis anterior (TA) muscles were affected in different degrees. Methods Two patients aged 39and 41 years were included. Patient 1 had PPMA for 8 years and his TA muscle strength was 3-/5, whereas Patient 2 showed PPMA findings for 1 year and his TA strength was 4/5. CMAP scan of TA muscle on recently affected side was performed with a commercially available software. In scanning EMG, MU territories were scanned with a concentric needle electrode (CNE) which is attached to a stepper motor. Another CNE is used for sweep triggering with the rate of selected motor units’ firing frequency. Acquired signals were processed by the dedicated software designed by the authors. Results CMAP scan of Patient 1 revealed a 1.65 mV CMAP constituting of 4 very large steps and Patient 2 revealed a 5.5 mV CMAP containing a few smaller steps. In scanning EMG, both patients’ motor units showed increased voltage in different parts corresponding to dense areas arisen from collateral reinnervation. Interestingly, the patient with more pronounced weakness for a longer period revealed both huge steps in his CMAP scan and also showed electrically silent areas in his scanned motor units. On the other hand, the patient with stronger TA muscle did not show very large steps or silent areas in his CMAP scan and MU scan, respectively. Conclusion Loss of dense motor units leads to PPMA. However, in PPMA patients with severe weakness which is depicted by less number of motor units and presence of huge steps in CMAP scan, loss of fractions in motor unit territory might be a principal contributing factor which can only be demonstrated by scanning EMG.

PURPOSE The aims were to assess the excitability of motor cortex and trigeminal structures in patients with primary headaches experiencing allodynia and to investigate the alterations in interictal allodynia and blink reflex excitability after repetitive transcranial magnetic stimulation (rTMS). METHODS Patients with strictly lateralized primary headaches were included, and Allodynia Symptom Checklist was used to detect allodynia. Paired transcranial magnetic stimulation and blink reflex recovery studies were performed on both sides. Ten Hertz or sham rTMS was applied on the motor cortex in patients with interictal allodynia. Allodynic symptoms were registered quantitatively, and blink reflex study was repeated after these trials. RESULTS Seventeen of 34 patients with headache described allodynia. Our findings showed bilateral hyperexcitability of cortical and trigeminal structures in the allodynic group. Interictal allodynia, detected in 13 allodynic patients, improved after rTMS as compared with sham stimulation, and this effect appeared to be more evident in the late period. CONCLUSIONS Bilateral increases in the cortical and trigeminal excitability were shown in patients with allodynia, and rTMS was effective for reducing clinical allodynia. The authors suggest that allodynic condition of the patients should be taken into account in the planning and evaluation of electrophysiological studies, and rTMS may be considered as a treatment alternative for troublesome allodynia.

Peripheral nerve hyperexcitability (PNH) syndromes can be subclassified as primary and secondary. The main primary PNH syndromes are neuromyotonia, cramp-fasciculation syndrome (CFS), and Morvan’s syndrome, which cause widespread symptoms and signs without the association of an evident peripheral nerve disease. Their major symptoms are muscle twitching and stiffness, which differ only in severity between neuromyotonia and CFS. Cramps, pseudomyotonia, hyperhidrosis, and some other autonomic abnormalities, as well as mild positive sensory phenomena, can be seen in several patients. Symptoms reflecting the involvement of the central nervous system occur in Morvan’s syndrome. Secondary PNH syndromes are generally seen in patients with focal or diffuse diseases affecting the peripheral nervous system. The PNH-related symptoms and signs are generally found incidentally during clinical or electrodiagnostic examinations. The electrophysiological findings that are very useful in the diagnosis of PNH are myokymic and neuromyotonic discharges in needle electromyography along with some additional indicators of increased nerve fiber excitability. Based on clinicopathological and etiological associations, PNH syndromes can also be classified as immune mediated, genetic, and those caused by other miscellaneous factors. There has been an increasing awareness on the role of voltage-gated potassium channel complex autoimmunity in primary PNH pathogenesis. Then again, a long list of toxic compounds and genetic factors has also been implicated in development of PNH. The management of primary PNH syndromes comprises symptomatic treatment with anticonvulsant drugs, immune modulation if necessary, and treatment of possible associated dysimmune and/or malignant conditions.

Familial Mediterranean fever (FMF) is an inherited inflammatory disease characterized by recurrent febrile polyserositis. Central nervous system (CNS) involvement in FMF is uncommon, but recently cases with multiple sclerosis (MS) and FMF have been reported. Here we assess patients with both FMF and MS, in order to clarify any relationship between FMF and MS, and to evaluate disease characteristics. Our MS database between 1986–2005 was screened retrospectively, and patients with both FMF and inflammatory/demyelinating CNS disease were evaluated among a total of 2800 patients including definite MS (n = 2268) and other demyelinating disorders. There were 12 patients with FMF, who developed a CNS disorder with multifocal white matter lesions. Median age at onset of FMF was 7 years, and median age at neurological onset was 26.8 years. Nine patients (including two siblings) had definite MS according to clinical and MRI findings, whereas 3 patients had atypical features suggesting other demyelinating disorders. Disease severity varied among the patients between very mild to a fatal course. All 8 patients evaluated for oligoclonal IgG bands in CSF were positive. The rate of FMF among our patients with definite MS is almost 4 times the expected prevalence in Turkey. Our series including a sibling pair concordant for FMF and MS may suggest that similar genetic susceptibility and environmental factors might be responsible, although coincidence still remains a possibility. A prospective study on a larger sample seems to be justified.

Pudendal nerve entrapment (PNE) is a common cause of resistant and disabling perineal pain. Although it is diagnosed clinically, neurophysiological tests are used for the diagnosis. Since the complaints worsen in the sitting position, routine pudendal somatosensory evoked potentials (SEP) performed in the supine position with midline stimulation may fail to show the PNE. We hypothesized that diagnostic value of SEP can be increased by stimulating the right and left sides separately along with provocation by maintained sitting position (dynamic SEP). Forty-nine patients with PNE and 16 healthy controls were included. SEP recordings were performed by stimulating the dorsal nerve of penis/clitoris on either side. The recordings were performed at the first supine position, at the beginning and end of a standardized sitting posture and at the second supine position. Regarding the patients with recordable responses, we might suggest that approximately 45% decrease in SEP amplitude or an amplitude value less than 1.5 mV at the termination of the sitting position (and their reversal with switching to the supine position again) are the parameters to be used with high selectivity. The dynamic pudendal SEP study described herein seems to be more valuable in PNE diagnosis than conventional SEPs.

Objectives Some patients with Carpal Tunnel Syndrome (CTS) complain of dropping objects. In this study, the clinical and electrophysiological features of CTS patients with (wOD) and without object dropping (w/oOD) were compared. Methods 52 female cases (age range: 21–80) consisting of 20 wOD, 16 CTS w/oOD patients and 16 healthy controls were included. Clinical evaluation included neurological examination, hand preference questionnaire, Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), a questionnaire for frequent object dropping and records of weekly hand usage. Nerve conduction studies (NCSs) were composed of bilateral orthodromic median 2nd finger and ulnar 5th finger sensory NCSs, median-ulnar ring finger sensory latency comparison, and median and ulnar motor NCSs. Median nerve was stimulated at palm, wrist and elbow. Conduction velocity and compound muscle action potential (CMAP) amplitude loss across the wrist was calculated. Results In wOD cases, mean age was older (59 vs. 53 years), symptom duration (42 vs. 29 months) and weekly occupational hand usage times (47 vs. 39 h) were longer, BCTQ symptom severity (2.9 vs. 2.5) and functional status scores (3.1 vs. 2.4) were higher. Sensory and motor NCSs abnormalities were more prominent on the dominant side in wOD, while they were similar on the non-dominant side in both groups. CMAP amplitude loss across the wrist was higher on the dominant side in wOD (27.8% vs. 13.3%). Discussion and conclusion Frequent object dropping may be a sign of severity and chronicity in CTS. Significance The relation between frequent object dropping and clinical and electrophysiological severity of CTS was investigated.

Objective Compound muscle action potential scanning (CMAP scan) is a non-invasive electrophysiological tool that allows observation of the whole-range of the functional motor unites in a muscle. The objective of this study is to assess the changes in CMAP scan from abductor pollicis brevis (APB) and abductor digiti minimi (ADM) muscles during the diagnosis and follow up period in amyotrophic lateral sclerosis (ALS) patients. Method Seventeen patients with ALS and 15 healthy controls (HCs), were included in the study. Five hundred stimuli were applied with equal steps in descending order at 2 Hz, in order to generate a CMAP scan curve. The data were exported to Microsoft Excel 2007. Backward step% step%, gap%, D50 were calculated. Results Backward step% step%, gap%, D50 values for ADM muscle were 264, 22.6, 27.9, 23.4 in ALS and 179.3, 1.9, 1.8, 46.7 in the control group, respectively (p ⩽ 0.05, between ALS and HC groups). Backward step% step%, gap%, D50 values for APB muscle were 500.6, 41.3, 39.9, 20.5 for ALS group and 241.7, 3.6, 3, 46.4 for the control group (p ⩽ 0.05, between ALS and HC groups). In ALS patients, backward step%, step%, gap% were found to be more severely affected in APB muscle. Follow-up studies of 6 patients showed significant difference in step%, gap% in APB muscle and D50, step% in ADM muscle. Conclusion CMAP scan is a sensitive electrophysiological method for showing the motor unit changes caused by ALS and for observing the effects of split-hand phenomenon.

Objective The aim of the study is to evaluate the diagnostic value of triple stimulation technique (TST) and cortical excitability studies as markers of upper motor neuron degeneration in ALS patients and to compare the extent of electrophysiological changes in abductor pollicis brevis (APB) and abductor digiti minimi (ADM) muscles. Methods Fifteen patients with ALS and 15 healthy controls (HCs) were included in the study. Motor evoked potential (MEP) responses, contralateral and ipsilateral silent periods (ISP) and paired-stimulation tests were recorded from both hypothenar and thenar muscles simultaneously. Paired-stimulation studies were performed with interstimulus intervals (ISI) of 2 and 3 ms for short-interval intracortical inhibition (SICI) and 10 and 12 ms for intracortical facilitation. TST responses were recorded from APB and ADM muscles. Results ISP duration was significantly shorter in the ALS group both for ADM and APB muscles (31.1 and 27.6 ms in ALS; 43.3, 39.3 ms in HCs respectively). SICI with 2 ms was reduced from thenar and hypothenar muscles in ALS patients when compared with HCs. MEP amplitudes were lower in ALS patients. TST test/control values in ADM and APB muscles were lower in ALS patients (86.4 and 73.7 in ALS; 100.8 and 107.8 in HCs respectively). Although TSTtest/control values had a tendency to be higher in the ADM, the results of the TMS studies were not significantly different between ADM and APB muscles in ALS patients. Conclusion These findings may be indicators of increased cortical excitability together with the upper motor neuron degeneration in ALS patients.

Objectives Some patients with Carpal Tunnel Syndrome (CTS) complain of difficulty in gripping and dropping objects. Occupationally extensive and long-term use of the hands is a risk factor for CTS. In this study, the prevalence of CTS and object dropping complaints were analysed in relation to body-Mass Index (BMI) and anthropometric hand measurements in a group of dentists with long working hours. Methods 79 dentists (53 females, mean age 28.5 ± 3.9) and 50 age and gender-matched controls [30 females, mean age 26.4 ± 5.8] were included. Clinical examination, hand preference questionnaire, Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), anthropometric measurements of the hands and a questionnaire for frequent object dropping were performed. Electromyography was performed in 21 dentists and 10 controls. Results Weekly occupational hand usage was higher in dentists than controls [33.6 ± 13 vs 12.8 ± 13 h]. The prevalence of frequent object dropping was also higher in dentists (24.1% vs 10%). Although symptoms suggestive of CTS were present in 13 dentists, objective CTS findings were found in only 1. Clinical examination and BCTQ findings showed no significant difference between the groups. There were no significant correlation between the anthropometric measurements and BCTQ scores and frequent object dropping. Discussion and conclusions The probable cause of the low prevalence of CTS in our dentist group may be the young age. The complaint of frequent object dropping can be explained by their increased awareness about their hand function. Significance The relation between object dropping, CTS and the associated features were investigated in a group with occupational excessive hand usage.

Objectives Repeater F-waves (Freps) were seen in patients with amyotrophic lateral sclerosis (ALS). The factors implicated for the presence and frequency of Freps were loss of the motor neurons and the changes in their excitability. The aim of this study was to assess the Freps in ALS patients and to compare their frequencies in thenar and hypothenar muscles. Methods Sixteen ALS patients and 11 healthy controls were recruited to the study. All patients had ⩾2 mV CMAPs recorded from the hand muscles. Ninety F-waves were recorded from abductor digiti minimi (ADM) and abductor pollicis brevis (APB). The index of repeater neurons (RN) and Freps were calculated. Results Mean index RN and index Freps values of ADM and APB muscles in ALS group (17.1 and 42.6 for ADM and 16.3 and 41.9 for APB) were significantly higher than those of healthy controls (4.7 and 13.9 for APB and 1.5 and 3.6 for ADM). ALS group had a lower persistence of F-waves for both muscles than healthy controls (56.4 and 94.6 for APB and 83.4 and 97.0 for ADM). Freps parameters were not different between thenar and hypothenar muscles, whereas persistence of F-waves was lower in the thenar (56.4%) as compared to the hypothenar (83.4%) muscles. Discussion Similar Freps parameters in the thenar and hypothenar muscles might be caused by the inclusion criteria. Lower F-persistence in the thenar muscles was in accordance with the split-hand phenomenon. Conclusion The assessment of Freps and F persistence may be useful in understanding of the electrophysiological changes in ALS.

Objectives To study the electrophysiological parameters of swallowing and related brainstem reflexes before and after bilateral mandibular sagittal split osteotomy in patients with mandibular dentoskeletal deformities. Methods The patients were divided into 3 groups based on the occlusion pattern, Group I (Angle Class III malocclusion, 7 patients), Group II (Angle Class II malocclusion, 4 patients) and Controls (Class I occlusion, 12 healthy subjects). Swallowing reflex with 3–20 ml water bolus, blink reflexes (BR) with supraorbital and mental nerve stimulation, and masseter inhibitory reflex (MIR) during maximal intercuspidation were studied. Electrophysiological tests were repeated postoperatively in 2nd and 7th months. Results Oral preparation and triggering the pharyngeal phase of swallowing was shorter in Group II (especially with 15–20 ml water) and longer in Group I, as compared to the controls. Oral period shortened after surgery in Group I. In Group II, 2 patients had piecemeal deglutition during swallowing of 10–20 ml water, and one of them became normal after surgery. At the postoperative 2nd month examination, BR with mental nerve stimulation was suppressed bilaterally (with a unilaterally absent MIR) in one patient in Group I and unilaterally in one patient in Group II, with subsequent recovery. Discussion and conclusion Oral phase of swallowing is shorter in Group II, possibly due to the low volume capacity of the oral cavity. BR and MIR abnormalities substantiates the reversible inferior alveolar nerve damage. Significance This study combines the electrophysiological swallowing tests and brainstem reflexes in patients with mandibular malocclusion both before and after surgery.

Objective Electrophysiological diagnosis of ulnar nerve entrapment at the wrist is sometimes difficult. The aim was to evaluate the diagnostic role of ulnar nerve stimulation above and below the Guyon channel in ulnar nerve entrapment at the wrist. Methods Supramaximal ulnar nerve stimulation at the wrist and palm, in addition to the standard nerve conduction studies, in 10 patients with ulnar nerve entrapment at the wrist and 40 controls. Results Motor latencies to the first dorsal interosseous muscle with wrist stimulation were prolonged unilaterally in six and bilaterally in four patients. Palmar stimulation showed partial conduction blocks on the more symptomatic side in all. In two bilateral cases, there were 28.8% and 44.3% amplitude loss on the less symptomatic side. Motor responses elicited with palm stimulation were also found to have prolonged latencies and decreased amplitudes. Conclusions Stimulation of the deep branch of the ulnar nerve can expand the information about ulnar nerve entrapment at the wrist by providing evidence about its nature, prognosis, precise localization, and distal extent.

PURPOSE Identification of abnormal motor unit potentials (MUP), in particular those caused by myopathic processes, is generally difficult in facial muscles because the MUPs are already low in amplitude and short in duration. Therefore, quantitative measures for the limits of abnormality are needed more frequently for these muscles, especially for the pathological processes predominantly affecting the craniofacial area. In this study, we aimed to determine some quantitative values that may help us to differentiate "myogenic" and "neurogenic" processes in periocular muscles. METHODS The frontalis muscle was examined unilaterally with multi-MUP and interference pattern analyses in 32 normal subjects, 31 patients with different types of myopathy, and 13 patients with facial palsy. Abnormality limits were calculated by using five previously suggested methods, two of which were based on group means and the other three on determining the outlier values. The sensitivity and specificity of multi-MUP and interference pattern parameters in discriminating abnormal findings by using these different methods were analyzed. RESULTS Statistically significant differences for all MUP parameters, except for the frequency, was found between the groups (P < 0.001). Motor unit potential duration, size index, and amplitude were the most valuable parameters for distinguishing the individual abnormalities. However, their discriminating power was higher for neuropathies than for myopathies. Interference pattern analysis was found not to have any superior sensitivity to MUP analysis. In this study, the outlier analysis that depends on the 5th to 95th percentile limits of the pooled data provided the best power for the discrimination of both neuropathies and myopathies from normal subjects. CONCLUSION Multi-MUP analysis seems to be helpful in differentiating the patients with neurogenic and-to a lesser extent-myogenic facial muscle involvement.

In 2 patients with neuromyotonia, nerve blocks had no effect on the abnormal activity, while intramuscular injection of the botulinum toxin abolished the discharges in one and greatly diminished them in the other. Botulinum toxin thus helps to localize the origin of the neuromyotonic discharges to the terminal regions of the peripheral nerve in those cases where the more proximal portions cannot be held responsible.