Contralateral Facial Innervation in Healthy Subjects and in Patients with Peripheral Facial Palsy.

Background: We aimed to investigate the extent of the response of the orbicularis oris muscle to stimulation of the contralateral facial nerve both in patients with peripheral facial palsy (PFP) and in healthy subjects. Methods: EMG was performed at 2-6 weeks after the onset of PFP in the patient group and at any time in the healthy control group. We performed nerve conduction testing, electroneurography, and surface and needle EMG. Results: A total of 276 participants (patients/healthy controls: 218/58) were analyzed. The extent of the response of the contralateral orbicularis oris muscles to facial nerve stimulation was higher in healthy controls compared to that in the affected group. The response of the contralateral orbicularis oris muscles to stimulation of the paralyzed facial nerve was more extensive in those patients to whom glucocorticoid or physical therapy had been given. Cross-facial innervation in the orbicularis oris muscle extended up to 1.5 cm in one-third of healthy controls and was higher than that in those with PFP. Glucocorticoid or physical therapy seemed to improve cross-innervation in facial palsy. Conclusions: Our findings suggest that the stimulus leading to the contralateral muscular response is mediated through crossing axons rather than muscular fibers.

What does epileptic nystagmus show us in cases presenting acute neurological symptoms?

PURPOSE: This study aims to determine the clinical significance of epileptic nystagmus in patients with acute neurological symptoms. METHOD: The clinical findings of patients with documented epileptic nystagmus, their original video and EEG data, and cranial imaging and laboratory tests were analyzed retrospectively. RESULTS: 20 patients were included in the study and 21 epileptic nystagmus attacks were determined from patients' clinical and video-EEG recordings. All recorded seizures with epileptic nystagmus were focal onset in nature. The ictal discharge pattern was rhythmic fast activity with a mean frequency of 15 Hz. The ictal discharges originated from the parieto-occipital (n = 8), temporo-occipital (n = 7), parieto-occipito-temporal (n = 3), temporal (n = 2), occipital (n = 1), and centroparietal (n = 1) areas. In the fast phase, the nystagmus was beating away from the side of ictal discharges. The origin of the ictal discharges on EEG images was compatible with the lesion localization at cranial MRI in all patients. Etiologies were epilepsy in seven patients, non-ketotic hyperglycemia in four, ketotic hyperglycemia in one, PRES in three, acute stroke in three, HSV encephalitis in one, and MELAS in one. CONCLUSIONS: Epileptic nystagmus represents a guide to the lateralization and localization of the lesion in cases presenting with acute neurological symptoms. In these patients, the lesion is frequently in the posterior regions of the hemispheres. Although various diseases affect these regions in terms of etiology, such cases should be evaluated in terms of the presence of hyperglycemia.

An Unusual Case Presenting with New Onset Epileptic Seizure and Unilateral Temporal Lobe Lesion Diagnosed as Influenza Type A Associated Encephalitis.

Influenza A viruses, known etiological agents of seasonal outbreaks, epidemics, and pandemics, are RNA viruses of the Orthomyxoviridae family. They can manifest with a wide range of neurological complications. Influenza related encephalitis is rarely reported and poorly characterized in adults. Its diagnosis is hampered by significant variation in clinical presentation and difficulties in virus detection in the cerebrospinal fluid. Diffuse brain edema, symmetric involvement of thalamus, brain stem, and cerebellum, or normal findings in the acute phase followed by the appearance of diffuse low attenuation and mild brain atrophy are reported cranial magnetic resonance imaging findings, but unilateral temporal lobe involvement has not been observed before. Here we describe an unusual adult case who presented with new-onset epileptic seizures and unilateral temporal lobe lesion mimicking herpes simplex encephalitis but a polymerase chain reaction of cerebrospinal fluid confirmed influenza type A associated encephalitis.

Neuropathic Pain Frequency in Neurology Outpatients: A Multicenter Study.

INTRODUCTION: Neuropathic pain is common, but the frequency of misdiagnosis and irrational treatment is high. The aim of this study is to evaluate the rate of neuropathic pain in neurology outpatient clinics by using valid and reliable scales and review the treatments of patients. METHODS: The study was conducted for 3 months in eleven tertiary health care facilities. All outpatients were asked about neuropathic pain symptoms. Patients with previous neuropathic pain diagnosis or who have neuropathic pain symptoms were included and asked to fill painDETECT and douleur neuropathic en 4 questions (DN4) questionnaire. Patients whose DN4 score is higher than 3 and/or painDETECT score higher than 13 and/or who are on drugs for neuropathic pain were considered patients with neuropathic pain. The frequency of neuropathic pain was calculated and the treatments of patients with neuropathic pain were recorded. RESULTS: Neuropathic pain frequency was 2.7% (95% CI: 1.5-4.9). The most common cause was diabetic neuropathy. According to painDETECT, the mean overall pain intensity was 5.7±2.4, being lower among patients receiving treatment. Pharmacological neuropathic pain treatment was used by 72.8% of patients and the most common drug was pregabalin. However, 70% of those receiving gabapentinoids were using ineffective doses. Besides, 4.6% of the patients were on medications which are not listed in neuropathic pain treatment guidelines. CONCLUSION: In our cohort, the neuropathic pain severity was moderate and the frequency was lower than the literature. Although there are many guidelines, high proportion of patients were being treated by ineffective dosages or irrational treatments.

Treatment of Intractable Midbrain Tremor with a Pedinculopontine Nucleus Radiofrequency Lesion.

In this report, we present the case of a 21-year-old female with midbrain tremor involving atypical features, treated using a pedinculopontine nucleus lesion. Different targets for the treatment of midbrain tremor using radiofrequency lesion have been reported. In this case, stimulation of the thalamic ventralis intermedius nucleus and subthalamic nucleus produced no satisfactory improvement in tremor frequency and amplitude. A third goal was to obtain a significant response in terms of these outcomes with pedinculopontine nucleus stimulation. According to the literature, this is the first case of midbrain tremor treated with a pedinculopontine nucleus radiofrequency thermocoagulation lesion.

Neuromyelitis optica presenting with horner syndrome: A case report and review of literature.

Neuromyelitis optica (NMO) is a demyelinating disease of the central nervous system that predominantly affects the spinal cord and optic nerves. We describe a 19 years old woman with left Horner syndrome (HS), who was diagnosed as NMO with characteristic longitudinally extensive myelitis and positive serum aquaporin-4 immunoglobulin G antibodies (AQP4-IgG). Our report describes one of the very rare ocular motor symptoms in NMO patients.

The effects of the cerebral, cerebellar and vestibular systems on the head stabilization reflex.

The head stabilization reflex (HSR) is a brain stem reflex which appears in the neck muscles in response to sudden head position changes and brings the head to its previous position. The reflex mechanism has not been understood. The afferent fibers come from cervical muscle spindles, vestibular structures, and the accessory nerve, the efferents from the accessory nerve. In this study, we aim to investigate the roles of supraspinal neural structures and the vestibular system on the HSR. The patient group consisted of 86 patients (33 cerebral cortical lesion, 14 cerebellar syndrome and 39 vestibular inexcitability or hypoexcitability); the control group was composed of 32 healthy volunteers. Concentric needle electrodes were inserted into the sternocleidomastoid muscle (SCM) and the accessory nerves were stimulated with the electrical stimulator. A reflex response of about 45-55 ms was obtained from the contralateral SCM muscle. 50 % of cases had bilateral loss whereas 37 % of cases with unilateral cerebellar lesions had an ipsilateral reflex loss. Bilateral HSR loss was detected in 84 % of cases with bilateral cerebellar lesions. Bilateral reflex loss was observed in 70 % of patients with unilateral cortical lesions and 94 % of those with bilateral vestibular dysfunction. Ipsilateral HSR loss was observed in 55 % of cases with unilateral vestibular dysfunction. It was discovered that supraspinal structures and the vestibular system may have an excitatory effect on HSR. This effect may be lost in supra-segmental and vestibular dysfunctions. The localization value of HSR was found to be rather poor in our study.

Eagle syndrome: case report.

Eagle syndrome is an aggregate of symptoms caused by an elongated styloid process, most frequently resulting in headache, facial pain, dysphagia and sensation of foreign body in throat. The proper diagnosis is not difficult with clinical history, physical examination and radiographic assessment if there is a sufficient degree of suspicion. The treatment is very effective. We report here a typical case of Eagle syndrome which was misdiagnosed as trigeminal neuralgia for many years and was treated with carbamazepine. We aim to point the place of Eagle syndrome in the differential diagnosis of facial pain. We also re-emphasize the usefulness of the three-dimensional computed tomography in the diagnosis of Eagle syndrome. Even though Eagle syndrome is a rare condition, in cases of facial pain refractory to treatment or unexplained complaints of the head and neck region, it should be considered in the differential diagnosis as it has therapeutic consequences.

Sensory nerve conduction in branches of common interdigital nerves: a new technique for normal controls and patients with morton's neuroma.

In this article, a new electrodiagnostic approach is described for patients with Morton's neuroma. The new method is based on the anatomic fact that the two branches of the common plantar interdigital nerves innervate the lateral side of one toe and the medial side the next one. This study included 20 normal subjects (aged 28-58 years, 10 men and 10 women) and 4 patients with Morton's neuroma (aged 44-52 years, 4 women). The branches of adjacent common plantar interdigital nerves that innerve one toe were stimulated superficially and separately with half of one toe covered with a piece of medical tape. The recordings were obtained on the posterior tibial nerve at the medial malleolus with needle electrodes. Thus, the difference in latencies of obtained sensory nerve action potentials on the posterior tibial nerve with needle electrode was measured. From normal subjects' data, it was determined that a latency difference value of above 0.17 milliseconds (mean +/- 2.5 SD) in one toe was abnormal. All of the patients with Morton's neuroma showed abnormal interlatency difference values. This new method, which we have developed, is more sensitive, simple to use, does not require extra equipment, and does not cause excessive pain. We suggest that interlatency difference between branches of the common plantar interdigital nerves is a useful and sensitive method for the diagnosis of Morton's neuroma.

Differential effects of peripheral vibration on motor-evoked potentials in acute stages of stroke.

OBJECTIVE: The excitability of sensorimotor cortex and spinal motoneurones can be modulated by afferent signals arising from the periphery. Low- and high-frequency vibrations activate separate classes of afferent units in the periphery. Low-frequency vibrations (2-100 Hz) activate the type I fast adapting afferent units (FA-I), whereas high-frequency vibrations (60-1000 Hz) preferentially activate the type II units (FA-II). Muscle spindles are also sensitive to high-frequency mechanical vibrations. Motor-evoked potentials (MEP) generated in response to transcranial magnetic stimulation (TMS) can be modulated by afferent signals. However, it is not clear whether these interactions take place at cortical or spinal cord levels. METHODS: Cerebrovascular attacks resulting in stroke generally affect both sensory and motor systems. In eight stroke patients with partial motor deficit in the first two weeks of the incident we studies the effects of low- (30 Hz) and high- (130 Hz) frequency mechanical vibrations on the MEPs obtained in response to TMS. Recordings from the abductor digiti minimi muscle were carried out by TMS of both lesioned and intact hemispheres. Six patients were tested again four to eight weeks after the initial assessment. The results also were compared with data obtained from eight control subjects. MEPs were evoked by 50% above threshold intensities and for each testing condition initially five control MEPs were recorded. This was followed by consecutive MEPs obtained during vibration (N= 5) and between vibrations (N= 5), and the traces were averaged and analyzed. RESULTS: In normal subjects both low- (30 Hz) and high- (130 Hz) frequency vibration resulted in shortening of MEP latencies. In patients, there was a similar effect on the affected side with 30 Hz, but not with 130 Hz. Stimulation of the intact hemisphere during high-frequency vibration in the second test revealed a latency shortening, which could be due to central reorganization. The amplitude of MEPs showed a stronger facilitation in the presence of low-frequency vibration in the early stage of stroke compared with normal subjects. However, in the second test the level of facilitation was reduced, indicating an effect at the cortical level. CONCLUSIONS: The results suggest that a cerebrovascular accident influences the modulatory effects of afferent inputs at both spinal and cortical levels, and in time, as reorganization takes place, these altered influences settle towards normal levels.

Morphology and innervation of the human cremaster muscle in relation to its function.

The electromyographic properties of the cremaster muscle (CM) are quite different from other skeletal muscles. It shows excessive spontaneous discharges, and the motor unit shape and firing frequency of the CM muscle differ from that of limb muscles. In this study, CM of six adult cadavers and six orchiectomy specimens were used to reveal the detailed histology of the muscle and provide an anatomophysiological explanation for these unusual electromyographic properties. Routine histochemical stains revealed the CM was composed of several distinct bundles of smooth and striated muscle fibers within connective tissue. The smooth muscle fibers that were more profuse than previously known and were not arranged in layers, but widely dispersed between striated muscle fibers. Bielschowsky silver staining technique, anti-neurofilament and anti-synaptophysin immunostaining showed the presence of multiple motor end-plates observed as a series of small dots or lines running along the striated muscle fibers and several nerve endings on a single muscle fiber. Myosin immunostaining confirmed the CM is a slow-twitch muscle, and alpha-actin smooth muscle immunostaining confirmed the presence of a large number of smooth muscle fibers. There were also small multipolar neurons forming nerve plexuses between smooth muscle fibers. Anti-GFAP immunostaining confirmed the presence of glial cells similar to astrocytes. In conclusion, the findings of this detailed anatomical study showed the CM, widely known as a striated muscle, contains a large number of smooth muscle fibers, and the spontaneous electromyographic discharges are due to the presence of multiple motor end-plates and dense innervation.

Electrodiagnostic pattern approach for childhood polyneuropathies.

Electrophysiologic studies play a key role in the detection and characterization of the pattern in childhood polyneuropathies. In this study, the etiologic profile of 74 children with polyneuropathy was prospectively evaluated based on the electrophysiologic studies. Five electrodiagnostic patterns were identified in the cohort: (1) acute axonal polyneuropathy (n: 32, 43%); (2) chronic axonal polyneuropathy (n: 16, 22%); (3) demyelinating motor and sensory polyneuropathy (n: 13, 17%); (4) pure sensory polyneuropathy (n: 11, 15%); (5) high-low syndrome (n: 2, 3%). Etiologic factors were identified in all of the patients with three electrodiagnostic patterns of polyneuropathy: acute axonal, pure sensory, and high-low syndrome. However, etiologic factors could not be determined in 5 (31%) children with chronic axonal polyneuropathy and in 3 (23%) children with demyelinating sensory and motor polyneuropathy. Among children with the acute axonal pattern, toxic causes were evident in 18 (56%), acute motor axonal neuropathy in 11 (35%), and acute motor sensory axonal polyneuropathy in 3 (9%). Nine (82%) patients with pure sensory polyneuropathy had diabetes mellitus. In conclusion, a thorough history and physical examination in conjunction with specific electrodiagnostic patterns might provide a cost-effective and rational differential diagnosis of childhood polyneuropathies.

Electrophysiological evaluation of the genitofemoral nerve in patients with inguinal hernia.

Groin pain in the lower abdomen but including the ilioinguinal region is frequent after inguinal hernia operations, but the integrity of the nerves in this region, including the genitofemoral nerve (GFN), has not been investigated. We studied GFN motor conduction time to the cremasteric muscle (CM), the CM electromyogram (EMG), and the CM reflex in 30 patients with unilateral inguinal hernia who underwent herniorrhaphy and in 26 similar patients who had no surgical intervention. Among the 30 patients undergoing herniorrhaphy, 14 (47%) showed motor involvement of the GFN, whereas 6 of the 26 (23%) patients not treated surgically had involvement of the GFN. These findings indicate that subclinical motor involvement of the GFN can be demonstrated by electrophysiological methods and is common after inguinal herniorrhaphy. Based on patient complaints, the herniated mass may also be responsible for motor involvement of the GFN in some patients before surgery.

Cutaneous silent periods of the vastus medialis evoked by the stimulation of lateral femoral cutaneous nerve.

OBJECTIVE: Cutaneous silent period (CSP), which is a spinal reflex mediated by A-delta cutaneous afferents, is transient suppression of the electromyographic activity. In this study, our aim is to investigate CSPs of vastus medialis muscle (vm-CSP) evoked by the stimulation of the lateral femoral cutaneous nerve (LFCN) in healthy controls and in patients with meralgia paresthetica (MP). METHODS: Twenty-one patients with MP (17 unilateral, 4 bilateral) and 27 healthy controls were included. Nerve conduction studies of LFCN and vm-CSP were analyzed in all subjects. A stimulus train consisting of five electrical shocks was applied to the skin at the anterolateral side of the thigh for recording of the vm-CSP. RESULTS: Nerve conduction abnormalities of LFCN were observed in all patients with MP. Mean duration of vm-CSP was 69.7+/-9.2ms, and mean onset latency was 44.7+/-6.9 in healthy controls. Onset latency of vm-CSP was significantly prolonged and the duration of vm-CSP was significantly shortened in patients with MP. Vm-CSP abnormalities were observed in 20/25 extremities with MP. CONCLUSIONS: Dysfunction of A-delta afferents may cause these findings in patients with MP. Additionally, spinal modulation of pain may also play a role in the explanation of our findings. SIGNIFICANCE: The present study demonstrates the CSP alterations in the patients with entrapment neuropathy of a cutaneous nerve.

Corticonuclear innervation to facial muscles in normal controls and in patients with central facial paresis.

Recently it has been proposed that corticobulbar innervation of the lower facial muscles is bilateral, that is from both right and left sides of the motor cortex. The objectives of this study were, i) to evaluate the corticonuclear descending fibers to the perioral muscles and, ii) to determine how central facial palsy (CFP) occurs and often recovers rapidly following a stroke. Eighteen healthy volunteers and 28 patients with a previous history of a stroke and CFP (mean ages: 51 and 61 years) were investigated by TMS (transcranial magnetic stimulation) with a figure of eight coil. Intracranial facial nerve and cortical motor evoked potentials (MEPs) were recorded from the perioral muscles. The periorbital MEPs were also studied. The absence of MEPs in both perioral muscles with TMS of the affected hemisphere was the most obvious abnormality. Also, central conduction time was significantly prolonged in the remaining patients. The mean amplitude of the affected hemisphere MEPs was diminished. The amplitudes of the unaffected hemisphere MEPs recorded from the intact side were enhanced especially in the first week following the stroke. During TMS, only the blink reflexes were elicited from the periorbital muscles due to stimulus spreading to trigeminal afferent nerve fibers. It is concluded that perioral muscles are innervated by the corticobulbar tract bilaterally. CFP caused by a stroke is generally incomplete and mild because of the ipsilateral cortical and multiple innervations out of the infarction area, and recovers fast through cortical reorganisation.

[Memory of pain]. / Agri hafizasi

Duration and recalling of pain, occurring by stimulated unmyelinated C and A-delta fibers, can be described as memory of pain. The memory of pain is a process that executes in from dorsal horn sensory neurons to cingulate cortex in brain. This description includes hyperalgesia and synaptic plasticity.

Effects of lamotrigine on the symptoms and life qualities of patients with post polio syndrome: a randomized, controlled study.

The aim of this study is to find out if lamotrigine gives symptomatic relief and enhances quality of life in patients with post-polio syndrome. Thirty patients were randomly assigned to receive or not to receive lamotrigine treatment. Lamotrigine at a daily dose of 50-100 mg was given to the fifteen patients, and fifteen patients were used as the control group. Interventional advice and home exercises were given to all of the patients. Clinical assessments were made at baseline and repeated at the second and fourth weeks by the physician who was unaware of medication. The severity of pain, fatigue and muscle cramps were rated on a visual analogue scale. Health-related quality of life was measured using the Nottingham Health Profile. The patient's perceived level of fatigue was assessed using Fatigue Severity Scale. Comparing to the baseline values, statistically significant improvements were obtained in the mean scores of VAS, NHP and FSS at two weeks and four weeks in the patients on lamotrigine. No significant improvements were reported in the control group. These preliminary results indicate that lamotrigine relieves the symptoms and improves the life qualities of patients with post polio syndrome.

Differential corticomotor control of a muscle adjacent to a painful joint.

OBJECTIVE: To assess the effects of chronic knee pain on neural control of the nearby quadriceps muscle. METHODS: Motor-evoked potentials (MEP) in response to transcranial magnetic stimulation (TMS) of the motor cortex, maximal M responses, patellar tendon responses, and EMG activity during maximal isometric contraction were recorded from the right vastus medialis oblique (VMO) and vastus lateralis (VL) muscles in 13 patients with chronic patellofemoral pain syndrome (PPS) and 13 healthy volunteers. MEP and maximal M responses were also recorded from the right extensor digitorum brevis (EDB) muscle. RESULTS: MEP amplitudes from VMO and VL were larger in patients with PPS than in controls. On the other hand, maximal M responses, EMG activity with maximal voluntary contraction, and tendon responses were smaller in patients than in controls. Motor-evoked responses and maximal M responses of the EDB muscle did not show significant difference between the 2 groups. CONCLUSIONS: These results indicate that chronic knee pain modulates central motor control of an adjacent muscle.