-Classical textbooks and recent publications about the anatomy of the dorsal cutaneous branch of the ulnar nerve are revisited and correlated with methods of measurement of its conduction velocity, in order to evaluate the indications and limitations of the procedure. Etiology and pathogenesis of isolated lesions of this nerve branch are discussed.KEY WORDS: dorsal cutaneous ulnar nerve, anatomy, nerve conduction velocity, peripheral neuropathy, handcuff neuropathy, pricer palsy.Ramo dorsal do nervo ulnar: avaliação sobre a anatomia, neuropatias e utilidade do exame da velocidade de condução para diagnóstico RESUMO -O conhecimento da anatomia normal de um nervo e de suas variantes tem importantes implicações na indicação, realização e interpretação do exame neurofisiológico do mesmo. Apresentamos avaliação sobre aspectos anatômicos clássicos e recentes sobre o ramo dorsal do nervo ulnar. Correlacionamos marcas anatômicas ao método de medida da sua velocidade de condução e discutimos causas e mecanismos patogênicos das lesões deste ramo nervoso. PALAVRAS -CHAVE: ramo dorsal do nervo ulnar, anatomia, velocidade de condução nervosa, neuropatia periférica, neuropatia por algemas, paralisia após movimentos repetitivos.In order to correctly interpret the results of conduction velocity studies of a particular nerve, it is mandatory to know its anatomy, the most frequent territory of innervation, anatomical variants and their frequency. In this paper we review the above items regarding the dorsal cutaneous branch of the ulnar nerve (DCU).DCU provides all sensory modalities of the medial portion of the dorsal aspect of the hand and the dorsal surfaces of the proximal and medial phalanges of the fifth and fourth fingers 1 . The remainder of the dorsum of the hand is innervated by the superficial radial nerve 1 . Variability in this distribution has been documented 2-5 . DCU and superficial radial nerve conduction velocities have been employed in the investigation of the detailed innervation pattern of the fingers, and a sensory map was proposed 5 . Accumulation of data on DCU anatomy and on the innervation of the dorsum of the hand is useful to devise an appropriate sampling strategy of the nerves of interest. This must be programmed before and during testing, so that results may help to decide between normality, anatomical variants and disease. Several authors6-11 studied DCU electrophysiology. Among them, Jabre 6 and Kim et al. proposed similar techniques to measure DCU conduction velocity. Two publications are available from our country 12,13 . Both have studied reference values, but the techniques employed were different.

-We analyzed the experience of Unicamp Clinical Hospital with plasma exchange (PE) therapy in myasthenia gravis (MG). About 17.8 % of a totality of MG patients had PE performed: 26 cases, 19 women and seven men. The mean age-onset of MG was 28 years, extremes 11 and 69. Minimum deficit observed in the group was graded IIb (O & G) or IIIa (MGFA scale). One patient had prethymectomy PE. In seven the procedures were performed due to myasthenic crisis and in 18 patients due to severe myasthenic symptoms or exacerbation of previous motor deficit. Two patients were also submitted to chronic PE considering refractoriness to other treatments. Twenty-six patients had 44 cycles of PE and 171 sessions. The mean number of sessions was 3.9 (SD ± 1.4) each cycle; median 5, extremes 2 and 6. The mean time by session was 106,5 minutes (SD ± 35.2); median 100.5 (extremes of 55 and 215).The mean volume of plasma exchanged in each session was 2396 ml (SD ± 561); median 2225 (extremes 1512 and 4500). Side effects occurred: reversible hypotension (seven cases), mild tremor or paresthesias (seven cases). Infection and mortality rates due to PE were zero. All patients had immediate benefit of each PE cycle and usually they also received prednisone or other immunosuppressors. Good acceptance of the procedure was observed in 80.7% of patients.KEY WORDS: plasmapheresis, myasthenia gravis, therapeutics, acceptance, complications. Plasmaférese no tratamento da miastenia grave: estudo retrospectivo de 26 pacientes RESUMO -Analisamos a experiência do Hospital das Clínicas da Unicamp com plasmaferese: (PF) na miastania grave (MG). 17,8 % do total dos casos de MG submeteu-se a PF, 26 casos, 19 mulheres e sete homens. A idade média de início da MG foi 28 anos (extremos 11 e 69). O menor déficit clínico foi IIb (O & G) e IIIa (MGFA).A PF foi indicada no pré-operatório de timectomia em um caso e em sete devido a crise miastênica. Em 18 casos, com MG generalizada e sintomas bulbares ou com exacerbação de déficit prévio, a PF foi indicada como intervenção aguda. Em dois pacientes desse grupo ela foi indicada também em regime crônico de ciclos mensais. Os 26 pacientes submeteram-se a 44 ciclos e a 171 sessões de PF. O número médio de sessões em cada ciclo foi 3,9 (DP ± 1,4); mediana de 5, extremos 2 e 6. O tempo médio de cada sessão foi 106,5 minutos (DP ± 35,2); mediana de 100,5 (extremos 55 e 215).O volume médio de plasma trocado em cada sessão foi 2396 ml (DP ± 561); mediana 2225 (extremos 1512 e 4500). Efeitos colaterais foram reversíveis: hipotensão (sete casos), tremor ou parestesias leves (sete casos). Taxas de infecção e mortalidade devido a PF foram zero. A totalidade dos pacientes teve benefícios imediatos a cada ciclo de PF e usualmente receberam prednisona ou outro imunossupressor. Houve boa aceitação ao procedimento em 80,7% dos pacientes.

Ganglionopathies (GNP), also known as sensory neuronopathies, are a group of conditions characterized by primary and selective damage to the dorsal root ganglia (DRG) of the spinal cord and sensory nuclei of the brainstem 1,2 . The etiologies are diverse and include immune-mediated diseases, vitamin deficiencies, drug toxicity, paraneoplastic syndromes and genetic causes, but many patients are yet defined as idiopathic 1,2 . The clinical presentation is characterized by diffuse, often asymmetric, sensory deficits and marked ataxia due to loss of proprioception 1,2 .In neurological practice, it is important to differentiate GNP from polyneuropathies (PNP) because the etiologies, therapeutic strategies and prognosis are often diverse 3 . Clinically, GNP can be distinguished from PNP due to a purely sensory dysfunction and the absence of length-dependent gradient of involvement. Often it is not possible to define a clear pattern of symmetry or predominant distal involvement (either by clinical or electrophysiological criteria), making it difficult to distinguish a GNP from a sensory PNP. ABSTRACTThe objective of this study was to evaluate if the ratio of ulnar sensory nerve action potential (SNAP) over compound muscle action potential (CMAP) amplitudes (USMAR) would help in the distinction between ganglionopathy (GNP) and polyneuropathy (PNP). Methods: We reviewed the nerve conductions studies and electromyography (EMG) of 18 GNP patients, 33 diabetic PNP patients and 56 controls. GNP was defined by simultaneous nerve conduction studies (NCS) and magnetic resonance imaging (MRI) abnormalities. PNP was defined by usual clinical and NCS criteria. We used ANOVA with post-hoc Tukey test and ROC curve analysis to compare ulnar SNAP and CMAP, as well as USMAR in the groups. Results: Ulnar CMAP amplitudes were similar between GNP x PNP x Controls (p=0.253), but ulnar SNAP amplitudes (1.6±3.2 x 11.9±9.1 x 45.7±24.7) and USMAR values (0.3±0.3 x 1.5±0.9 x 4.6±2.2) were significantly different. A USMAR threshold of 0.71 was able to differentiate GNP and PNP (94.4% sensitivity and 90.9% specificity). Conclusions: USMAR is a practical and reliable tool for the differentiation between GNP and PNP.Key words: clinical neurophysiology, ganglionopathy, polyneuropathy, sensory neuronopathy, ulnar nerve. RESUMOO objetivo deste estudo foi avaliar se a razão entre as amplitudes dos potenciais de ação sensitivo (SNAP) e motor (CMAP) do nervo ulnar (USMAR) auxiliaria na distinção entre ganglionopatia (GNP) e polineuropatia (PNP). Métodos: Revisamos os estudos de neurocondução e eletromiografia de 18 pacientes com GNP, 33 com PNP diabética e 56 controles. GNP foi definida pela presença simultânea de anormalidades na neurocondução e na ressonância magnética cervical. PNP foi definida por critérios clínicos e neurofisiológicos usuais. Usamos o teste ANOVA com Tukey post-hoc e análise da curva ROC para comparar o SNAP e CMAP ulnares, assim como o USMAR entre os grupos. Resultados: As amplitudes dos CMAPs ulnares foram similares entre GNP x P...

-We investigated the reference values of the dorsal ulnar cutaneous nerve (DUC) sensory nerve conduction (SNC) in 66 healthy individuals. Measurements were processed using stimulating electrodes positioned between the ulnar bone and the flexor carpi ulnaris muscle, 11-13 cm proximal to the active electrode recording. Superficial recording electrodes were placed on the fourth intermetacarpal space. The mean sensory conduction velocity (SCV) in males was 63.7 -0.16 x age ± 3.36 m/s and in females was 57.7 ± 3.37 m/s. The mean sensory nerve action potential (SNAP) amplitude in males was 19.5 ± 10.7 µV and in females was 24.6 ± 5.8 µV. The mean SNAP duration was 0.96 ± 0.13 ms. No significant differences regarding the DUC-SCV, distal latency, and SNAP duration or amplitude were found between both sides of the same subject. The amplitude of the SNAP was higher in females than males. The effects of age on DUC-SCV were distinct for each gender.KEY WORDS: dorsal ulnar cutaneous nerve, nerve conduction, reference values, age, height, sex, temperature.Condução nervosa do nervo cutâneo ulnar dorsal: valores de referência Condução nervosa do nervo cutâneo ulnar dorsal: valores de referência Condução nervosa do nervo cutâneo ulnar dorsal: valores de referência Condução nervosa do nervo cutâneo ulnar dorsal: valores de referência Condução nervosa do nervo cutâneo ulnar dorsal: valores de referência RESUMO -Investigamos os valores de referência da condução nervosa sensitiva do nervo cutâneo ulnar dorsal em 66 indivíduos normais, por técnica de condução nervosa antidrômica. A velocidade de condução sensitiva (VCS) média, em homens foi 63,7 -0,16 x idade ± 3,36 m/s e nas mulheres 57,7 ± 3,37 m/s. A amplitude média do potencial de ação nervoso sensitivo (PANS) em homens foi 19,5 ± 10,7 µV e nas mulheres foi 24,6 ± 5,8 µV. A duração média do PANS foi 0,96 ± 0,13 ms. A dominância manual não interferiu nos valores da VCS, latência distal, amplitude e duração do PANS. Nas mulheres a amplitude do PANS foi maior do que nos homens. Os efeitos da idade na VCS foram distintos para cada sexo. PALAVRAS-CHAVE: nervo cutâneo ulnar dorsal, condução nervosa, valores de referência, altura, idade, sexo, temperatura.The dorsal ulnar cutaneous nerve (DUC), a branch of the ulnar nerve, leaves the main ulnar trunk approximately at the junction of the medial and distal thirds of the forearm 1 , then it takes a dorsal position at the wrist and continues on the dorsomedial region of the hand 2 . The purposes of studying the DUC sensory nerve conduction (SNC) include distinction between proximal and distal ulnar nerve lesions 3-5 , identification of isolated lesions of this nerve branch 5,6 , and investigation of the dorsomedial hand innervation 6,7 .The DUC is vulnerable to laceration, blunt trauma, and compression injury due to its superficial position 8 . In addition, determination of the DUC-SNC is helpful to confirm or rule out proximal lesions of the ulnar nerve. Lesions of the ulnar nerve at the level of the elbow and wrist are highly fre...

-There are few papers devoted to geriatric Guillain-Barré (GBS) and many related issues re m a i n u n a n s w e re d . Objective: To describe clinical, electrophysiological and therapeutic features in this age. Method: Clinico-epidemiological data and therapy of GBS patients older than 60 years were reviewed. Hughes scores were used to quantify neurological deficit and define outcome. Results: Among 18 patients (mean age 64.8 years), 9 had evident pro d rome and 80% noticed initially sensory-motor deficit. Demyelinating GBS was found in 8 and axonal in 6 subjects. There was one Miller-Fisher and 3 unclassified cases. Plasmapheresis (PFX) was single therapy in 12 patients and intravenous immunoglobulin (IVIg) in 2. Disability scores just before therapy were similar in both groups, so as short and long term outcome. C o n c l usion: Axonal GBS seems to be more frequent in the elderly and this may have prognostic implications. PFX and IVIg were suitable options, but complications were noticed with PFX. Prospective studies are needed to better understand and manage GBS in the elderly.KEY WORDS: Guillain-Barré syndrome, plasmapheresis, intravenous immunoglobulin, elderly.S í n d rome de Guillain-Barré no idoso: aspectos clínico-eletrofisiológicos, terapêutico e pro g n ó stico RESUMO -Publicações sobre a síndrome de Guillain-Barré (SGB) no idoso são escassas e várias questões s o b re o tema estão abert a s . O b j e t i v o :D e s c rever aspectos clínico-eletrofisiológicos, terapêuticos e pro g n ó stico no idoso. Método: Revisamos os prontuários de pacientes acima de 60 anos com SGB. A escala de Hughes foi usada para quantificar os déficits iniciais e finais. Resultados: No total de 18 pacientes (média de idade 64,8 anos), 50% tiveram pródromo e 80% tiveram déficit sensitivo-motor no início. SGB desmielinizante foi encontrada em 8 pacientes, axonal em 6 e uma síndrome de Miller-F i s h e r. Três casos não puderam ser classificados. Plasmaférese (PFX) foi empregada isoladamente em 12 pacientes e imunoglobulina endovenosa (IVIg) em 2. A disfunção inicial nos dois grupos tratados era semelhante, assim como a evolução a curto e longo prazo. Conclusão: A forma axonal da SGB parece ser mais freqüente no idoso e isto pode ter implicações prognósticas. PFX e IVIg foram eficazes, mas complicações ocorreram apenas no gru p o tratado com PFX. Estudos prospectivos são necessários para um melhor entendimento e manejo da SGB no idoso. PALAVRAS-CHAVE: síndrome de Guillain-Barré, plasmaférese, imunoglobulina endovenosa, idosos.