The vascular and neurogenic factors associated with erectile dysfunction in patients after pelvic fractures

ABSTRACT Erectile dysfunction (ED) is a common complication of pelvic fractures. To identify the vascular and neurogenic factors associated with ED, 120 patients admitted with ED after traumatic pelvic fracture between January 2009 and June 2013 were enrolled in this study. All patients answered the International Index of Erectile Function (IIEF-5) questionnaire. Nocturnal penile tumescence (NPT) testing confirmed the occurrence of ED in 96 (80%) patients on whom penile duplex ultrasound and neurophysiological testing were further performed. Of these ED patients 29 (30%) were demonstrated only with vascular abnormality, 41 (42.7%) were detected only with neural abnormality, 26 (27.1%) revealed mixed abnormalities. Of the 55 patients (29+26) with vascular problems, 7 patients (12.7%) with abnormal arterial response to intracavernous injection of Bimix (15mg papaverine and 1mg phentolamine), 31 (56.4%) with corporal veno-occlusive dysfunction and 17 (30.9%) had both problems. Of the 67 (41+26) patients with abnormal neurophysiological outcomes, 51 (76.1%) with abnormal bulbocavernosus reflex (BCR), 20 (29.9%) with pathological pudendal nerve evoked potentials (PDEPs) and 25 (37.3%) with abnormal posterior tibial somatosensory nerve evoked potentials (PTSSEPs). Our observation indicated that neurogenic factors are important for the generation of ED in patients with pelvic fracture; venous impotence is more common than arteriogenic ED.

Effectiveness of hip muscle strengthening in patellofemoral pain syndrome patients: a systematic review

Introduction: Patellofemoral pain syndrome (PFPS) is characterized by anterior knee pain, which may limit the performance of functional activities. The influence of hip joint motion on the development of this syndrome has already been documented in the literature. In this regard, studies have investigated the effectiveness of hip muscle strengthening in patients with PFPS. Objectives: The aims of this systematic review were (1) to summarize the literature related to the effects of hip muscle strengthening on pain intensity, muscle strength, and function in individuals with PFPS and (2) to evaluate the methodological quality of the selected studies. Method: A search for randomized controlled clinical trials was conducted using the following databases: Google Scholar, MEDLINE, PEDro, LILACS, and SciELO. The selected studies had to distinguish the effects of hip muscle strengthening in a group of patients with PFPS, as compared to non-intervention or other kinds of intervention, and had to investigate the following outcomes: pain, muscle strength, and function. The methodological quality of the selected studies was analyzed by means of the PEDro scale. Results: Seven studies were selected. These studies demonstrated that hip muscle strengthening was effective in reducing pain. However, the studies disagreed regarding the treatments' ability to improve muscle strength. Improvement in functional capabilities after hip muscle strengthening was found in five studies. Conclusion: Hip muscle strengthening is effective in reducing the intensity of pain and improving functional capabilities in patients with PFPS, despite the lack of evidence for its ability to increase muscle strength. .

Combined Muscle Motor and Somatosensory Evoked Potentials for Intramedullary Spinal Cord Tumour Surgery

PURPOSE: To evaluate whether intraoperative neurophysiologic monitoring (IONM) with combined muscle motor evoked potentials (mMEPs) and somatosensory evoked potentials is useful for more aggressive and safe resection in intramedullary spinal cord tumour (IMSCT) surgery. MATERIALS AND METHODS: We reviewed data from consecutive patients who underwent surgery for IMSCT between 1998 and April 2012. The patients were divided into two groups based on whether or not IONM was applied. In the monitored group, the procedures were performed under IONM using 75% muscle amplitude decline weaning criteria. The control group was comprised of patients who underwent IMSCT surgery without IONM. The primary outcome was the rate of gross total excision of the tumour on magnetic resonance imaging at one week after surgery. The secondary outcome was the neurologic outcome based on the McCormick Grade scale. RESULTS: The two groups had similar demographics. The total gross removal tended to increase when intraoperative neurophysiologic monitoring was used, but this tendency did not reach statistical significance (76% versus 58%; univariate analysis, p=0.049; multivariate regression model, p=0.119). The serial McCormick scale score was similar between the two groups (based on repeated measure ANOVA). CONCLUSION: Our study evaluated combined IONM of trans-cranial electrical (Tce)-mMEPs and SEPs for IMSCT. During IMSCT surgery, combined Tce-mMEPs and SEPs using 75% muscle amplitude weaning criteria did not result in significant improvement in the rate of gross total excision of the tumour or neurologic outcome.

Intraoperative Neurophysiologic Monitoring: Basic Principles and Recent Update

The recent developments of new devices and advances in anesthesiology have greatly improved the utility and accuracy of intraoperative neurophysiological monitoring (IOM). Herein, we review the basic principles of the electrophysiological methods employed under IOM in the operating room. These include motor evoked potentials, somatosensory evoked potentials, electroencephalography, electromyography, brainstem auditory evoked potentials, and visual evoked potentials. Most of these techniques have certain limitations and their utility is still being debated. In this review, we also discuss the optimal stimulation/recording method for each of these modalities during individual surgeries as well as the diverse criteria for alarm signs.

A Case of Acute Polyneuropathy with Nephrotic Syndrome Showing Transient Proximal Sensory Conduction Defects

Acute sensorimotor polyneuropathy that resembles Guillain-Barre syndrome (GBS) is rarely accompanied with nephrotic syndrome, and its underlying immunological mechanisms are unclear. A 56-year-old man presented with simultaneous acute progressive symmetric sensorimotor polyneuropathy and proteinuria. A kidney biopsy revealed focal segmental glomerulosclerosis. Serial electrophysiologic studies showed only a transient proximal conduction block in the median nerve, stimulated somatosensory evoked potential and prolonged terminal latencies of the median and peroneal nerves. The patient's neurologic deficits and kidney dysfunction recovered with corticosteroid treatment. Our case showed that somatosensory evoked potential study can be an important objective tool in the diagnosis of acute polyneuropathy with normal distal nerve conduction and that corticosteroids should be considered in the initial treatment of GBS-resembling polyneuropathy associated with nephrotic syndrome.

Sequential Involvement of the Nervous System in Subacute Combined Degeneration

PURPOSE: Subacute combined degeneration (SCD) involves progressive degeneration of the spinal cord, optic nerve, and peripheral nerves. Vitamin B12 (VB12) is a co-factor in myelin synthesis. Because each cell that constitutes the myelin component in the central nervous system and peripheral nervous system is different, it is improbable that these cells undergo simultaneous degeneration. However, the sequence of degeneration in SCD has not been established. MATERIALS AND METHODS: In this study, we analysed medical records and electrophysiological data of patients who showed neurological symptoms and whose serum VB12 levels were lower than 200 pg/mL. RESULTS: We enrolled 49 patients in this study. Their mean VB12 level was 68.3 pg/mL. Somatosensory evoked potential (SEP) study showed abnormal findings in 38 patients. Of the 40 patients who underwent visual evoked potential (VEP) study, 14 showed abnormal responses. Eighteen patients showed abnormal findings on a nerve conduction study (NCS). In this study, abnormal posterior tibial nerve SEPs only were seen in 16 patients, median nerve SEPs only were seen in 3 patients, abnormal VEPs only in two, and abnormal NCS responses in one patient. No patient complained of cognitive symptoms. CONCLUSION: In SCD, degeneration appears to progress in the following order: lower spinal cord, cervical spinal cord, peripheral nerve/optic nerve, and finally, the brain.

Motor cortex electric stimulation for the treatment of neuropathic pain / Estimulação elétrica do córtex motor no tratamento da dor neuropática

OBJECTIVE: Motor cortex stimulation (MCS) is considered to be an effective treatment for chronic neuropathic pain. The aim of the present study was to assess the efficacy of MCS for treating neuropathic pain. METHOD: 27 patients with chronic neuropathic pain were operated. Electrodes were implanted with the use of an stereotactic frame. Electrophysiological evaluations (motor stimulation and somatosensory evoked potentials) were performed, with guidance by means of three-dimensional reconstruction of magnetic resonance images of the brain. 10 patients (37 percent) presented central neuropathic pain (post-stroke pain) and 17 others (63 percent) presented peripheral neuropathic pain (brachial plexus avulsion, phantom limb pain or trigeminal pain). RESULTS: In 15 patients (57.7 percent) the pain relief was 50 percent or more; while in ten patients (38.5 percent), more than 60 percent of the original pain was relieved. No differences were found in relation to central and peripheral neuropathic pain (p=0.90), pain location (p=0.81), presence of motor deficit (p=0.28) and pain duration (p=0.72). No major complications were observed. CONCLUSION: MCS was efficient for treating patients presenting chronic central or peripheral neuropathic pain.

OBJETIVO: A estimulação do córtex motor (ECM) é método considerado eficaz no tratamento da dor neuropática crônica rebelde. O presente estudo avaliou a eficácia da ECM no tratamento de pacientes portadores de dor neuropática crônica. MÉTODO: 27 doentes foram avaliados; 10 (37,0 por cento) apresentavam dor neuropática de origem central, enquanto 17 (63,0 por cento), dor neuropática periférica. Avulsão de raízes do plexo braquial, dor no membro fantasma, dor decorrente de doença cerebrovascular isquêmica ou hemorrágica ou neuropatia trigeminal foram as causas mais freqüentes da dor. Os doentes foram operados com uso da técnica de localização estereotáctica do córtex motor associadamente a estudo eletroneurofisiológico (estimulação motora e potencial evocado somatossensitivo) ou ainda com uso de imagens de ressonância magnética do encéfalo reconstruídas tridimensionalmente. RESULTADOS: O alívio da dor foi igual ou superior a 50 por cento em 15 doentes (57,7 por cento), sendo em 10 (38,5 por cento), superior a 60 por cento. Não houve diferença nos resultados quanto a origem central ou periférica (p=0,90) da dor, localização da dor (p=0,81), ocorrência ou não de déficit motor (p=0,28) e duração da sintomatologia (p=0,72). Não foram observadas complicações graves. CONCLUSÃO: A estimulação do córtex motor foi útil no tratamento da dor neuropática crônica rebelde tanto de origem central como periférica.

Topographic distribution of the tibial somatosensory evoked potential using coherence

The objective of the present study was to determine the adequate cortical regions based on the signal-to-noise ratio (SNR) for somatosensory evoked potential (SEP) recording. This investigation was carried out using magnitude-squared coherence (MSC), a frequency domain objective response detection technique. Electroencephalographic signals were collected (International 10-20 System) from 38 volunteers, without history of neurological pathology, during somatosensory stimulation. Stimuli were applied to the right posterior tibial nerve at the rate of 5 Hz and intensity slightly above the motor threshold. Response detection was based on rejecting the null hypothesis of response absence (significance level α= 0.05 and M = 500 epochs). The best detection rates (maximum percentage of volunteers for whom the response was detected for the frequencies between 4.8 and 72 Hz) were obtained for the parietal and central leads mid-sagittal and ipsilateral to the stimulated leg: C4 (87 percent), P4 (82 percent), Cz (89 percent), and Pz (89 percent). The P37-N45 time-components of the SEP can also be observed in these leads. The other leads, including the central and parietal contralateral and the frontal and fronto-polar leads, presented low detection capacity. If only contralateral leads were considered, the centro-parietal region (C3 and P3) was among the best regions for response detection, presenting a correspondent well-defined N37; however, this was not observed in some volunteers. The results of the present study showed that the central and parietal regions, especially sagittal and ipsilateral to the stimuli, presented the best SNR in the gamma range. Furthermore, these findings suggest that the MSC can be a useful tool for monitoring purposes.

Pudendal somatosensory evoked potentials in normal women

OBJECTIVE: Somatosensory evoked potential (SSEP) is an electrophysiological test used to evaluate sensory innervations in peripheral and central neuropathies. Pudendal SSEP has been studied in dysfunctions related to the lower urinary tract and pelvic floor. Although some authors have already described technical details pertaining to the method, the standardization and the influence of physiological variables in normative values have not yet been established, especially for women. The aim of the study was to describe normal values of the pudendal SSEP and to compare technical details with those described by other authors. MATERIALS AND METHODS: The clitoral sensory threshold and pudendal SSEP latency was accomplished in 38 normal volunteers. The results obtained from stimulation performed on each side of the clitoris were compared to ages, body mass index (BMI) and number of pregnancies. RESULTS: The values of clitoral sensory threshold and P1 latency with clitoral left stimulation were respectively, 3.64 ± 1.01 mA and 37.68 ± 2.60 ms. Results obtained with clitoral right stimulation were 3.84 ± 1.53 mA and 37.42 ± 3.12 ms, respectively. There were no correlations between clitoral sensory threshold and P1 latency with age, BMI or height of the volunteers. A significant difference was found in P1 latency between nulliparous women and volunteers who had been previously submitted to cesarean section. CONCLUSIONS: The SSEP latency represents an accessible and reproducible method to investigate the afferent pathways from the genitourinary tract. These results could be used as normative values in studies involving genitourinary neuropathies in order to better clarify voiding and sexual dysfunctions in females.

Pré-condicionamento isquêmico e monitorização da função medular na abordagem da aorta torácica descendente / Ischemic preconditioning and spinal cord function monitoring in the descending thoracic aorta approach

OBJETIVOS: Avaliar a eficácia do pré-condicionamento isquêmico (PI) agudo, guiado por potenciais evocados somatossensoriais (PESS), como método de proteção medular em cães e analisar o valor dos PESS na monitorização da função medular. MÉTODOS: Foram utilizados 28 cães submetidos à isquemia medular obtida pelo pinçamento da aorta torácica descendente. No grupo C45, o tempo de oclusão aórtica foi de 45 min (n = 7); no grupo PI45, os cães foram submetidos ao PI antes do pinçamento aórtico por 45 min (n = 7). No grupo C60, os cães foram submetidos a 60 min de oclusão aórtica (n = 7) e no grupo PI60, os cães foram submetidos ao PI, seguido pelo pinçamento aórtico por 60 min. Os ciclos de PI foram determinados pelas alterações dos PESS. RESULTADOS: Os índices de Tarlov dos grupos pré-condicionados foram significativamente melhores que os dos grupos de controle (p = 0,005). Observou-se paraplegia em três cães do C45 e em seis do C60, enquanto todos os cães do PI45 permaneceram neurologicamente normais, assim como quatro do grupo PI60. Houve correlação entre o tempo de recuperação dos PESS após a reperfusão aórtica e o estado neurológico pós-operatório (p = 0,011), com sensibilidade e especificidade de 0,75 e 0,83, respectivamente. CONCLUSÃO: O PI agudo repetitivo, baseado na monitorização do PESS, induziu proteção à isquemia medular causada pelo pinçamento aórtico prolongado. A monitorização do PESS parece ser um bom método de detecção precoce do comprometimento isquêmico medular.

OBJECTIVES: To evaluate the effectiveness of acute ischemic preconditioning (IP), based on somatosensory evoked potentials (SSEP) monitoring, as a method of spinal cord protection and to asses SSEP importance in spinal cord neuromonitoring. METHODS: Twenty-eight dogs were submitted to spinal cord ischemic injury attained by descending thoracic aorta cross-clamping. In the C45 group, the aortic cross-clamping time was 45 min (n=7); in the IP45 group, the dogs were submitted to IP before the aortic cross-clamping for 45 min (n=7). In the C60 group, the dogs were submitted to 60 min of aortic cross-clamping (n=7), as in the IP60 group that was previously submitted to IP. The IP cycles were determined based on SSEP changes. RESULTS: Tarlov scores of the IP groups were significantly better than those of the controls (p = 0.005). Paraplegia was observed in 3 dogs from C45 and in 6 from C60 group, although all dogs from IP45 group were neurologically normal, as 4 dogs from IP60. There was a significant correlation between SSEP recovery time until one hour of aortic reperfusion and the neurological status (p = 0.011), showing sensitivity of 75 percent and specificity of 83 percent. CONCLUSION: Repetitive acute IP based on SSEP is a protection factor during spinal cord ischemia, decreasing paraplegia incidence. SSEP monitoring seems to be a good neurological injury assessment method during surgical procedures that involve spinal cord ischemia.

Transplantation of canine umbilical cord blood-derived mesenchymal stem cells in experimentally induced spinal cord injured dogs

This study was to determine the effects of allogenicumbilical cord blood (UCB)-derived mesenchymal stemcells (MSCs) and recombinant methionyl humangranulocyte colony-stimulating factor (rmhGCSF) on acanine spinal cord injury model after balloon compressionat the first lumbar vertebra. Twenty-five adult mongreldogs were assigned to five groups according to treatmentafter a spinal cord injury: no treatment (CN); salinetreatment (CP); rmhGCSF treatment (G); UCB-MSCstreatment (UCB-MSC); co-treatment (UCBG). The UCB-MSCs isolated from cord blood of canine fetuses wereprepared as 10(6) cells/150microl saline. The UCB-MSCs weredirectly injected into the injured site of the spinal cord andrmhGCSF was administered subcutaneously 1 week afterthe induction of spinal cord injury. The Olby score,magnetic resonance imaging, somatosensory evokedpotentials and histopathological examinations were used toevaluate the functional recovery after transplantation. TheOlby scores of all groups were zero at the 0-week evaluation.At 2 week after the transplantation, the Olby scores in thegroups with the UCB-MSC and UCBG were significantlyhigher than in the CN and CP groups. However, there wereno significant differences between the UCB-MSC andUCBG groups, and between the CN and CP groups. Thesecomparisons remained stable at 4 and 8 week aftertransplantation. There was significant improvement in thenerve conduction velocity based on the somatosensory evokedpotentials. In addition, a distinct structural consistency ofthe nerve cell bodies was noted in the lesion of the spinalcord of the UCB-MSC and UCBG groups. These resultssuggest that transplantation of the UCB-MSCs resulted inrecovery of nerve function in dogs with a spinal cord injuryand may be considered as a therapeutic modality for spinalcord injury.

Use of magnitude-squared coherence to identify the maximum driving response band of the somatosensory evoked potential

The present study proposes to apply magnitude-squared coherence (MSC) to the somatosensory evoked potential for identifying the maximum driving response band. EEG signals, leads [Fpz'-Cz'] and [C3'-C4'], were collected from two groups of normal volunteers, stimulated at the rate of 4.91 (G1: 26 volunteers) and 5.13 Hz (G2: 18 volunteers). About 1400 stimuli were applied to the right tibial nerve at the motor threshold level. After applying the anti-aliasing filter, the signals were digitized and then further low-pass filtered (200 Hz, 6th order Butterworth and zero-phase). Based on the rejection of the null hypothesis of response absence (MSC(f) > 0.0060 with 500 epochs and the level of significance set at a = 0.05), the beta and gamma bands, 15-66 Hz, were identified as the maximum driving response band. Taking both leads together ("logical-OR detector", with a false-alarm rate of a = 0.05, and hence a = 0.0253 for each derivation), the detection exceeded 70 percent for all multiples of the stimulation frequency within this range. Similar performance was achieved for MSC of both leads but at 15, 25, 35, and 40 Hz. Moreover, the response was detected in [C3'-C4'] at 35.9 Hz and in [Fpz'-Cz'] at 46.2 Hz for all members of G2. Using the "logical-OR detector" procedure, the response was detected at the 7th multiple of the stimulation frequency for the series as a whole (considering both groups). Based on these findings, the MSC technique may be used for monitoring purposes.

Low-frequency oscillations in human tibial somatosensory evoked potentials

Oscilações da atividade elétrica cerebral têm sido associadas a funções sensoriais, de percepção e de cognição. O presente estudo objetiva investigar as oscilações de baixa freqüência, em particular da banda gama (30-110 Hz), durante estimulação do nervo tibial. Vinte e um voluntários foram estimulados com pulsos de corrente de 0,2 ms, freqüência de 5 Hz e intensidade mínima para produzir o movimento involuntário dos músculos intrínsecos do pé. Sinais EEG espontâneo e durante estimulação foram registrados na área somato-sensitiva primária. A análise tempo-freqüência indicou o efeito do artefato ao estímulo na banda de freqüência do potencial evocado somato-sensitivo (PESS) até aproximadamente 5 ms pós-estímulo. As oscilações até 100 Hz apresentaram maior contribuição relativa de potência ao PESS (aproximadamente 99%) e se mostraram significativamente diferentes (p<0,01) das freqüências da média coerente do EEG espontâneo. Além disso, a banda 30-58 Hz foi identificada como a de maior contribuição à morfologia do PESS do nervo tibial (p<0,0001).

Achados dos potenciais evocados somatossensitivos e motores na mielopatia associada oa HTLV-I / Somatosensitive and motor evoked potentials in HTLV-I associated mylopathy

Foram estudados 63 pacientes com diagnóstico de paraparesia espástica tropical/ mielopatia associada ao HTLV-I (PET/ MAH) através de potencial evocado somatossensitivo (PESS) e 42 destes pacientes através de potencial evocado motor (PEM). Todos os pacientes apresentaram história clínica típica de MAH e sorologia para HTLV-I confirmada por Western blot. Dos pacientes estudados por PESS 51/63 (81 por cento) alterados em membros inferiores e 11 (17,5 por cento) deles estavam também em membros superiores. Dos pacientes estudados por PEM 37/42 estavam alterados, 34/42 (81 por cento) em membros inferiores e 25/42 (59,5 por cento) em membros superiores. Um alto percentual da amostra apresentou alterações das vias corticoespinhais nos quatro membros ao PEM, e ausência de alterações em membros superiores ao PESS, evidenciando a correlação entre o tempo de condução motora central para membros superiores e a gravidade clínica da PET/ MAH (p<0,01). Não foi evidenciado correlação entre o tempo de historia clínica e os achados dos PESS e PEM (p=0,69).

Morte Encefálica / Brain Death

Justificativa e Objetivos: O anestesiologista tem participado de procedimentos cirúrgicos relativos aos transplantes de órgäos e tecidos que envolvem doadores com o diagnóstico de morte encefálica. Pode defrontar-se também com o problema nas unidades de recuparaçäo pós-anestésicas e unidades de terapia intensiva. O objetivo desta revisäo é verificar os novos critérios para o diagnóstico de morte encefálica. Conteúdo: O diagnóstico da morte encefálica envolve um exame clínico adequado e exames complementares. Na investigaçäo clínica deve ser feito o diagnóstico etiológico do coma. No exame clínico devem ser avaliados os reflexos do tronco cerebral, pupilar, corneano, nauseoso, óculo-vestibulares e os movimentos dos olhos. Os exames complementares utilizados para o diagnóstico da morte encefálica säo divididos segundo o tipo de parâmetro fisiológico estudado pela angiografia cerebral, cintilografia radioisotópica, tomografia por emissäo de fóton único, tomografia cerebral com xenônio, tomografia por emissäo de positrons e doppler transcraniano. A atividade metabólica cerebral é estudada pela tomografia por emissäo de positrons. A atividade elétrica é avaliada pelo EEG e pelos potenciais evocados somatossensitivos. Conclusöes: Com exame clínico acurado e alguns exames complementares pode-se hoje, com mais segurança, atestar a morte em pacientes com perda irreversível das funçöes cardiorrespiratórias e cerebrais

The monitoring of somatosensory evoked potentials and neurologic complications in aneurysm surgery

Somatosensory evoked potential (SSEP) changes during cerebral aneurysm surgery and their relationship to postoperative neurologic complications have been studied on many occasions. However, it is still a matter of debate whether SSEP monitoring is really helpful in detecting or preventing neurologic complications. We studied 87 patients undergoing aneurysm surgery of the anterior cerebral circulation and SSEPs were monitored in 60 of these patients. All patients were grade 2 by the subarachnoid hemorrhage (SAH) grading system. Median nerve SSEP was monitored for middle cerebral or internal carotid artery aneurysms and posterior tibial nerve SSEP for anterior cerebral artery aneurysms. A decrease in the cortical amplitude of more than 50%, compared with control, was considered significant and interventions were then taken to reverse the SSEP. The pre- and postoperative neurologic deficits of each patient were evaluated immediately before and after surgery. No significant difference was found in the incidence of postoperative neurologic complications in the SSEP monitored (15% [9/60]) and unmonitored patients (22% [6/27]). In the SSEP monitored patients, the amplitudes of SSEPs decreased significantly in 14 patients and 4 of these showed neurologic complications. However, SSEP amplitudes were not significantly changed in 46 patients, and 5 of these showed neurologic complications. Significant changes in the amplitude of SSEP might represent neuronal injury, but the absence of change in the SSEP cannot guarantee patient safety. Our results suggest that SSEP monitoring may be useful for detecting the danger of neuronal injury, but that it does not reduce the incidence of neurologic complications in aneurysm surgery.

Value of motor and somatosensory evoked potentials in assessment of motor function in cerebral palsy

Cerebral palsy is a static non progressive motor disability that occurs at birth or early childhood. It results of injury to the neuromotor components of the central nervous system. Evoked potentials [EPs] are neurophysiological investigations used to demonstrate the existence of central nervous system lesions and were used as a screening method for neuropediatric diseases. Motor and somatosensory evoked potential [SEP] are the most sensitive methods of evoked potentials. They can provide a noninvasive objective method of evaluating the central and peripheral nervous system. The present study included 20 Egyptian children, 11 males and 9 females ranging in age from 3 to 6 years with a mean age of 3.9 years, presenting with spastic diplegia. All patients had mild to moderate motor disability and I.Q. above 50. Control group included 20 children, age and sex-matched with patients group. We studied motor and somatosensory evoked potentials in those patients and their correlation with motor functions. Transcranial magnetic stimulation [TMS] to the right upper limb [abductor pollicis brevis muscle] and somatosensory evoked potentials testing from the right median nerve and the left posterior tibial nerve were used to assess function of the corresponding systems. Motor evoked potentials from the right upper limb showed significant delay in cortical latencies and significant prolongation of central motor conduction time in CP patients compared to control group. However, the amplitude of cortical response showed no significant changes. Somato-sensory evoked potentials of right median nerve showed significantly prolonged cortical N[19]/ P[22] absolute latency, N[13] - N[20], Erb's - N[20], N[13] - N[20] inter peak latencies respectively, however, Erb's, N[13], Erb's - N[13] absolute latencies and inter peak latency showed non significant changes but N[20] amplitude was significantly decreased. Somatosensory evoked potentials of the left posterior tibial nerve showed significant prolonged cortical and lumber absolute latencies and inter peak latency. Also, significant decrease of amplitude of cortical wave. A statistically highly significant positive correlation was observed between the hand function and N[20] amplitude [P < 0.01] of SEPs of the right median nerve while all other variables showed no statistically significant correlation with each other. Also, a statistically significant positive correlation was observed between the foot function and cortical amplitude [P < 0.05] of SEPs of the left posterior tibial nerve while all other variables showed no statistically significant correlation with each other. A tendency towards positive correlation was observed between hand functions and cortical latency [P < 0.09] of motor evoked potentials to the right abductor pollicis brevis muscle. We concluded that somatosensory evoked potentials are sensitive, non-invasive techniques for detection of the severity of motor impairment. We recommend MEPs and SSEPs as a relatively fast and effective means of assessing the functional integrity of the central nervous system in cerebral palsy patients

Estandarización del método y condiciones de registro de potenciales evocados somatosensoriales en cirugías correctivas de deformidades de la columna vertebral: estudio neurofisiológico en 82 casos quirúrgicos / Standardization of method and record conditions of somatosensorial evoked potentials in corrective surgery for deformities of the spine: neurophysiological study in 82 operated cases

Se han reportado alteraciones neurológicas posteriores a intervenciones quirúrgicas en corrección de deformidades de columna vertebral, debido al riesgo de lesión que se presenta, se ha utilizado la maniobra del "despertar" para valorar la integridad neurológica, siendo ésta insuficiente, por lo que se han establecido técnicas neurofisiológicas como potenciales evocados somatosensoriales (PES) valorando dicha integridad, este método sin ser invasivo, valora la vía somatosensorial evitando el riesgo de lesión medular. Sin embargo se han observado también en ocasiones falsas positivas y negativas con el mismo. Se estudiaron 82 pacientes, promedio de edad 15.4, a los que se les realizó SEP registrando en corteza y cuello y estimulación en tibial bilateral, no observando diferencia significativa en los registros antes y después de la cirugía p > 0.05. En 9 pacientes hubo falsas positivas y en 7 pacientes los potenciales fueron anormales, presentándose manifestaciones neurológicas posquirúrgicas desde parestesias hasta lesión medular. Debido al riesgo de lesión neurológica en dichas intervenciones se debe monitorizar no sólo con SEP la vía sensitiva, sino también la vía motora con algún otro método, para disminuir la incidencia de falsas positivas y negativas, y dar información más confiable al cirujano, para beneficio del paciente.

Somatosensory evoked potentials by paraspinal stimulation in acute transverse myelitis.

Somatosensory evoked potentials by paraspinal stimulation were studied in 6 patients with acute transverse myelitis. In one patient in whom posterior tibial somatosensory evoked potentials were not recordable, a poorly formed response was seen with paraspinal stimulation. Slowing of conduction across the involved segment was seen in the remaining 5 patients and fairly correlated with the clinical localization.