COVID-19 clinical manifestations in children and adolescents admitted to intensive care in the city of São Carlos, Brazil: a case series / Manifestações clínicas da COVID-19 em crianças e adolescentes admitidos para terapia intensiva na cidade de São Carlos: uma série de casos

INTRODUCTION: Children with COVID-19 may be asymptomatic or present a heterogeneous clinical presentation. The present case series aimed to report clinical manifestations of COVID-19 in children and adolescents admitted to pediatric intensive care units (PICU) in the city of São Carlos, Brazil, during 2020 and 2021. REPORTS: The subjects were six children aged 3 months to 13 years, with COVID-19. The data were collected from electronic charts. All cases were domestic contact with a COVID-19 case. Two cases had multisystem inflammatory syndrome (MIS-C) and one had jaundice and ascites. One case had a seizure. One case required invasive ventilation and two cases presented gastrointestinal symptoms. There were no deaths in the cases. The length of PICU stays varied from one to 16 days. CONCLUSION: In the six cases reported, COVID-19 clinical manifestations in children and adolescents who required intensive care in São Carlos revealed a heterogeneous presentation and no lethality. It is worth emphasizing that a history of contact with a symptomatic respiratory person should guide the suspicion of COVID-19 in children and indicate a proper follow-up, as COVID-19 may be severe in this population.

INTRODUÇÃO: Crianças com COVID-19 podem ser assintomáticas ou podem ter apresentação clínica heterogênea. O objetivo desta série de casos foi relatar as manifestações clínicas da COVID-19 em crianças e adolescentes internados em unidade de terapia intensiva pediátrica (UTIP) na cidade de São Carlos, Brasil, durante 2020 e 2021. RELATOS: Os casos foram seis crianças com idade entre 3 meses e 13 anos, com COVID-19. Os dados foram coletados do prontuário eletrônico. Todos os casos foram contactantes domiciliares de algum caso de COVID-19. Dois casos se apresentaram como síndrome multissistêmica inflamatória (MIS-C), sendo um destes com icterícia e ascite. Um caso manifestou convulsão. Um caso necessitou de ventilação mecânica invasiva e dois casos apresentaram sintomas gastrointestinais. Não foi observado óbito entre os casos e o tempo de permanência na UTIP variou de 0 a 16 dias. CONCLUSÃO: Nos seis casos relatados, a COVID-19 revelou manifestações clínicas variadas, com rápida resolução e não foi observado óbito. É importante enfatizar que a história de contato com uma pessoa sintomática respiratória deveria guiar a suspeita de COVID-19 em crianças e indicar acompanhamento, uma vez que esta doença pode ser grave nesta população.

Correction to: Arabica coffee fruits phenology assessed through degree days, precipitation, and solar radiation exposure on a daily basis.

The article was published with an erroneous rendering of Table 1. The correct rendering of this table is provided below. The original article has been corrected.

Arabica coffee fruits phenology assessed through degree days, precipitation, and solar radiation exposure on a daily basis.

Knowledge regarding reproductive cycle duration is important in terms of scheduling harvests and estimating coffee cultivars adaptability. Nine Coffea arabica cultivars were evaluated during two successive reproductive cycles. Dates of occurrence of the major blossoms, and the green and ripe fruits, on 64 branches for each cultivar, were registered during each reproductive cycle. These dates were used to calculate the duration of the fruit development (blossom to green) and ripening (green to ripe) phases, the quantities of degree days, precipitation, and solar radiation accumulated throughout each phase, and also degree days, precipitation, and radiation on a daily basis, all of which are novelties in coffee research. The differences between cultivars and reproductive cycles were tested by ANOVA. Cultivars were grouped in clusters according to the above-cited variables. Principally, the daily quantities of degree days and precipitation determined the differences between reproductive cycles and coffee cultivars during development phases. Early and very early cultivars accumulated high numbers of degree days.day-1, in periods of relatively good water availability, with high exposure to solar radiation. Late cultivars accumulated less degree days.day-1 and were exposed to lower amounts of daily solar radiation and longer periods of water scarcity. Regarding the fruit ripening phase, cultivars were principally distinguished by degree days and solar radiation on a daily basis. Two of the coffee cultivars were classified or confirmed as early and very early and another three as late and very late. One cultivar, Siriema, displayed an interesting conjugation of early and intermediate characteristics.

Modified simple decompression in the treatment of cubital tunnel syndrome: avoiding ulnar nerve subluxation.

OBJECTIVE: In this study, we propose a modification to the simple decompression technique that contains the ulnar nerve in the cubital fossa, thus preventing subluxation during forearm flexion movements. METHODS: Five consecutive patients with leprosy-associated cubital tunnel syndrome underwent surgery with the modified technique between July 2011 and October 2012. RESULTS: The most common symptoms were neuropathic pain and sensory changes (both 60%). On the McGowan scale, three patients maintained their preoperative score and two patients improved by two points, while on the Louisiana State University Health Sciences Center scale, two patients maintained the same scores, two improved by two points, and one improved by one point. Four patients were able to discontinue corticosteroid use. The mean follow-up time was 25.6 months (range 2-48 months). There were no recurrences or subluxations in the long-term. CONCLUSION: This alternative technique resulted in excellent functional results, as well as successful withdrawal from corticosteroids. Furthermore, it resulted in no ulnar nerve subluxations.

Modified simple decompression in the treatment of cubital tunnel syndrome: avoiding ulnar nerve subluxation / Descompressão simples modificada no tratamento da síndrome do túnel cubital: evitando subluxação do nervo ulnar

ABSTRACT Objective In this study, we propose a modification to the simple decompression technique that contains the ulnar nerve in the cubital fossa, thus preventing subluxation during forearm flexion movements. Methods Five consecutive patients with leprosy-associated cubital tunnel syndrome underwent surgery with the modified technique between July 2011 and October 2012. Results The most common symptoms were neuropathic pain and sensory changes (both 60%). On the McGowan scale, three patients maintained their preoperative score and two patients improved by two points, while on the Louisiana State University Health Sciences Center scale, two patients maintained the same scores, two improved by two points, and one improved by one point. Four patients were able to discontinue corticosteroid use. The mean follow-up time was 25.6 months (range 2-48 months). There were no recurrences or subluxations in the long-term. Conclusion This alternative technique resulted in excellent functional results, as well as successful withdrawal from corticosteroids. Furthermore, it resulted in no ulnar nerve subluxations.

RESUMO Objetivo Neste manuscrito apresentamos uma modificação da técnica de descompressão simples do nervo ulnar no túnel cubital que impede a subluxação do nervo em movimentos de flexão do antebraço. Métodos Foram incluídos cinco pacientes consecutivos acometidos por síndrome do túnel cubital (Hanseníase) submetidos à cirurgia entre 2011 e 2012. Resultados Os sintomas mais comuns foram dor neuropática e alterações sensitivas (60%). No pós-operatório, três pacientes mantiveram o mesmo escore e dois melhoraram dois pontos na escala de McGowan, enquanto na escala Louisiana State University Health Sciences Center, dois pacientes mantiveram o mesmo escore, dois melhoraram dois pontos e um melhorou um ponto. Os corticosteróides foram descontinuados em quatro pacientes. O tempo médio de seguimento foi 25,6 meses (variação 2-48 meses). Não foram observadas recorrência ou subluxação no longo prazo. Conclusões A técnica alternativa apresentou excelentes resultados funcionais e foi bem sucedida na retirada dos corticosteróides. Ademais, subluxações do nervo ulnar não foram observadas.

Hypertrophic Olivary Degeneration: A Neurosurgical Point of View.

Hypertrophic olivary degeneration (HOD) is a rare form of transsynaptic degeneration characterized by hypertrophy of the inferior olivary nucleus situated in the olivary body, part of the medulla oblongata, representing a major source of input to the cerebellum. HOD typically results from focal lesions interrupting connections from the inferior olive within the dentato-rubro-olivary pathway, a region also known as the triangle of Guillain-Mollaret (TGM) (red nucleus, inferior olivary nucleus, and contralateral dentate nucleus). Clinically, HOD presents classically as palatal tremor and can include dentatorubral tremor and/or ocular myoclonus. The pathologic changes associated with HOD feature radiologic changes with the inferior olivary nucleus appearing larger and increasing its T2-weighted signal intensity on magnetic resonance images. HOD is commonly managed with pharmacotherapy but may require surgical intervention in extreme cases. HOD has been found to develop as a consequence of any injury that disrupts the TGM pathways (e.g., pontine cavernoma).These findings highlight the critical importance of a thorough knowledge of TGM anatomy to avoid secondary HOD. We present a patient who developed HOD secondary to resection of a tectal plate cavernous malformation and review the literature with an emphasis on the current knowledge of this disorder.

Mortes por acidentes de transporte terrestre no Brasil: análise dos sistemas de informação do Ministério da Saúde

Este Texto para Discussão apresenta as estatísticas de mortes por acidente de transporte terrestre no Brasil em 2013, bem como a evolução das mortes totais e por modalidade de transporte nos últimos quinze anos, utilizando os dados de mortalidade do Ministério da Sáude e os de internações de vítimas de acidentes de trânsito. No Brasil morrem cerca de 43 mil pessoas por ano em acidentes de trânsito, sendo os usuários de motocicleta as maiores vítimas. Este texto procura também apresentar uma discussão sobre diretrizes gerais de políticas públicas necessárias para reduzir o número de acidentes de trânsito.

Envelhecimento populacional, gratuidades no transporte público e seus efeitos sobre as tarifas na Região Metropolitana de São Paulo / /Population aging and the effects of free public transport on the fares in the metropolitan region of São Paulo / /Envejecimiento de la población, gratuidad en el transporte público y sus efectos sobre las tarifas en la Región Metropolitana de São Paulo

No Brasil, estudantes, crianças de até quatro anos de idade e idosos com 65 anos ou mais têm direito a descontos parciais ou totais em viagens urbanas nos sistemas de transporte público. Esses descontos não são cobertos por fundos públicos, mas sim por subsídio cruzado cobrado dos demais usuários que pagam a tarifa cheia. Neste estudo, são estimados os efeitos do envelhecimento populacional sobre o preço das passagens do transporte público nas próximas quatro décadas na Região Metropolitana de São de Paulo (RMSP), a maior região metropolitana do país. As análises são baseadas nos dados da Pesquisa Origem-Destino, realizada em 2007 na RMSP, e nas projeções demográficas elaboradas pelo IBGE e pela Fundação Seade para 2020, 2030 e 2050. Considerando os diferentes períodos de projeção populacional, adaptou-se a técnica de padronização direta para simular as mudanças esperadas na composição das viagens do sistema de transporte, em termos de passageiros pagantes e não pagantes. Os resultados indicam que, no curto prazo (2020), o envelhecimento populacional estimado para ocorrer na RMSP teria efeito modesto sobre o número total e a composição etária das viagens realizadas no transporte público da região. No médio e longo prazos, contudo, o crescimento previsto na proporção de passageiros com gratuidades poderia ocasionar aumento no sobrepreço da tarifa, com elevação de seu valor em cerca de 10% e de 20%, caso seja mantido o mecanismo de subsídios cruzados...

In Brazil, students, children under four years of age and people aged 65 and over are entitled to partial or full concessions on urban travel in public transport systems. These discounts are not covered by public funding, but rather via cross-subsidization charged to the other service users who pay the full fare. In this study, the effects of population aging on public transport fares for the next four decades in the metropolitan region of São Paulo (MRSP), the largest metropolitan area in Brazil, are estimated. The analyses in this paper are based on data from the Pesquisa Origem-Destino (Origin-Destination Survey), carried out in 2007 in the MRSP, and on official population projections developed by IBGE (the Brazilian Institute of Geography and Statistics) and Fundação Seade (the Seade Foundation) for the years 2020, 2030 and 2050. Considering the different periods of population projection, the technique of direct standardization to simulate expected changes in the composition of public transport trips was utilized, in terms of paying and non-paying passengers. The results indicate that, in the short term (2020), population aging expected to occur in the MRSP should have a modest effect on the total number and age composition of public transport trips in the region. However, if the current cross-subsidization mechanism is maintained, the expected growth in the percentage of non-paying passengers could result in an increase in fares by about 10% and 20% in the medium and long terms...

En Brasil, los estudiantes, los niños menores de 4 años y las personas de 65 años o más tienen derecho a descuentos parciales o totales en los viajes urbanos en los sistemas de transporte público. Estos descuentos no son cubiertos por fondos públicos, sino por un subsidio cruzado cobrado a los demás usuarios de los servicios que pagan la tarifa completa. En este estudio, se estiman los efectos del envejecimiento de la población sobre el precio de los pasajes del transporte público en las próximas cuatro décadas en la Región Metropolitana de São Paulo (RMSP), la mayor región metropolitana del país. Los análisis se basan en los datos de la Encuesta de Origen-Destino realizada en 2007 en la RMSP y en las proyecciones demográficas elaboradas por el IBGE y por la Fundación SEADE para 2020, 2030 y 2050. Teniendo en cuenta los diferentes escenarios de proyección de la población, se utiliza la técnica de estandarización directa para simular los cambios esperados en la composición de los viajes del sistema de transporte en términos de pasajeros que pagan y que no lo hacen. Los resultados indican que, en el corto plazo (2020), el envejecimiento de la población estimado en la RMSP tendría un efecto modesto sobre el número total y la composición por edades de los viajes realizados en el transporte público de la región. En el mediano y el largo plazo, sin embargo, el aumento previsto de la proporción de pasajeros con el beneficio de la gratuidad podría causar un incremento del sobreprecio de la tarifa, con una elevación de su valor de entre el 10% y el 20%, en caso de mantenerse el mecanismo de subsidio cruzado...

Bloqueio atrioventricular avançado: uma manifestação incomum da endomiocardiofibrose / Advanced atrioventricular block: an unusual manifestation od endomyocardial fibrosis

A endomiocardiofibrose é uma causa importante de cardiopatia restritiva na zona tropical, ocasionalmente verificada no Brasil. Caracteriza-se pelo espessamento fibroso do endocárdio e do miocárdio subjacente, com progressão tardia para insuficiência cardíaca grave e prognóstico reservado. Relata-se aqui uma apresentação infrequente da doença: a insuficiência cardíaca de baixo débito, secundária a bloqueio atrioventricular avançado. O paciente foi tratado com sucesso por meio de implante de marcapasso DDD/R e encontra-se em classe funcional I (NYHA) há dois anos.

Endomyocardial fibrosis is an important cause of restrictive cardiomyopathy observed in tropical areas and has been occasionally found in Brazil. It is characterized by fibrous thickening of the endocardium and underlying myocardium with late progression to severe heart failure and poor prognosis. We report an unusual presentation of the disease: low output heart failure secondary to advanced atrioventricular block. The patient was successfully treated by implanting a DDD/R pacemaker and has been in functional class I (NYHA) for 2 years.

Quantitative parameters of facial motor evoked potential during vestibular schwannoma surgery predict postoperative facial nerve function.

BACKGROUND: Facial motor evoked potential (FMEP) amplitude ratio reduction at the end of the surgery has been identified as a good predictor for postoperative facial nerve outcome. We sought to investigate variations in FMEP amplitude and waveform morphology during vestibular schwannoma (VS) resection and to correlate these measures with postoperative facial function immediately after surgery and at the last follow-up. METHODS: Intraoperative orbicularis oculi and oris muscles FMEP data from 35 patients undergoing surgery for VS resection were collected, then analysed by surgical stage: initial, dural opening, tumour dissection (TuDis), tumour resection (TuRes) and final. FINDINGS: Immediately after surgery, postoperative facial function correlated significantly with the FMEP amplitude ratio during TuDis, TuRes and final stages in both the orbicularis oculi (p = 0.003, 0.055 and 0.028, respectively) and oris muscles (p = 0.002, 0.104 and 0.014, respectively). At the last follow-up, however, facial function correlated significantly with the FMEP amplitude ratio only during the TuDis (p = 0.005) and final (p = 0.102) stages for the orbicularis oris muscle. At both time points, postoperative facial paresis correlated significantly with FMEP waveform deterioration in orbicularis oculi during the final stage (immediate, p = 0.023; follow-up, p = 0.116) and in orbicularis oris during the TuDis, TuRes and final stages (immediate, p = 0.071, 0.000 and 0.001, respectively; follow-up, p = 0.015, 0.001 and 0.01, respectively). CONCLUSIONS: FMEP amplitude ratio and waveform morphology during VS resection seem to represent independent quantitative parameters that can be used to predict postoperative facial function. Event-to-baseline FMEP monitoring is quite useful to dictate when intraoperative changes in surgical strategy are warranted to reduce the chances of facial nerve injury.

Calli induction in leaf explants of coffee elite genotypes / Indução de calos em explantes foliares de clones elite de café

Three experiments were carried out with the objective of achieving high effectiveness in calli induction from high heterozygosis leaf explants of Coffea arabica through indirect somatic embryogenesis. A randomized-block design in a 2x5 factorial arrangement made up of two media [BOXTEL & BERTHOULY (1996) and TEIXEIRA et al. (2004)] and five C. arabica genotypes were used in the first experiment. In the second experiment the embryogenic calli production potential was evaluated in ten genotypes. Each of them was considered as a treatment. In the third experiment the variations in both 2.4-D (2.5 e 20µM) and 2-iP (2.5 e 20µM) concentrations in TEIXEIRA et al. (2004) medium and secondary media were evaluated. Crops were kept in a growth room under darkness, at 25±2oC. The medium described by TEIXEIRA et al (2004) was found to be superior when compared to that described by BOXTEL & BERTHOULY (1996) in the 2.2 and 7.2 genotypes. An opposite behavior was noticed in 4.2 genotype, that is, BOXTEL & BERTHOULY (1996) had medium superiority. Both 3.0 and 5.0 genotypes had the same behavior in both media studied, which shows that the somatic embryo production depends on the genotype. Calli induction depends on the 2-iP and 2.4 D ratio. The 20.0µM of 2.4-D and 20.0µM of 2-iP combination caused the highest embryogenic calli induction rate.

Visando a alcançar alta eficiência na indução de calos a partir de explantes foliares de plantas matrizes de C. arabica com alta heterozigose, por meio da embriogênese somática indireta, foram instalados três experimentos. O primeiro experimento foi conduzido em esquema fatorial 2x5, constituído de dois meios de cultura (BOXTEL & BERTHOULY, 1996 e TEIXEIRA et al., 2004) e cinco genótipos de C. arabica. No segundo experimento, foi avaliado o potencial de produção de calos embriogênicos em 10 genótipos, sendo cada genótipo considerado como um tratamento e, no terceiro experimento, foram avaliadas as variações nas concentrações de 2.4-D (2,5 e 20µM) e 2-iP (2,5 e 20µM) nos meios primário e secundário de TEIXEIRA et al. (2004). As culturas foram mantidas a 25oC, sob obscuridade. Para os genótipos 2.2 e 7.2, verificou-se a superioridade do meio de cultura Teixeira et al. (2004) em relação ao meio BOXTEL & BERTHOULY (1996). No genótipo 4.2, observou-se o comportamento inverso, ou seja, a superioridade do meio BOXTEL & BERTHOULY (1996). Os genótipos 3.0 e 5.0 apresentaram o mesmo comportamento em ambos os meios de cultura estudados, evidenciando que a produção de embriões somáticos é fortemente dependente do genótipo. A indução de calos depende da relação de 2-iP e 2.4-D. A combinação de 20.0µM of 2.4-D e 20.0µM of 2-iP promoveu a maior porcentagem de indução de calos embriogênicos.

The impact of subdural air collection on intraoperative motor and somatosensory evoked potentials: fact or myth?

BACKGROUND: Surgery in the semi-sitting position is susceptible to changes in motor (MEP) and somatosensory evoked potentials (SEPs), which are not related to neurological impairment. These changes have been suggested to be caused by the insulating effect of subdural air collection. This study sought to investigate the correlation of MEP and SEP final-to-baseline amplitude ratios to postoperative volumetry of frontoparietal subdural air collection. METHODS: Median nerve SEP and hand MEP findings of 47 patients operated on in the semi-sitting position were compared with 7 patients operated on in the supine position. Computed tomography was routinely performed on the 1st postoperative day in all patients, and subdural air volumetry was calculated. Final-to-baseline MEP and SEP amplitude ratios were calculated and correlated to subdural air volumetry. FINDINGS: SEP changed in 12 patients, and MEP changed in 7 patients. Postoperative subdural air collections were significantly different between the groups (semi-sitting group, mean 31.2 cm(3); supine group, mean 2 cm3; p = 0.000). For the SEP ratios, a moderate negative correlation with subdural volumetry was found in the semi-sitting group (p = 0.044). Conversely, there was no correlation in the subset of patients with SEP attenuation (p = 0.846). As concerns the MEP ratios, no correlation was demonstrated in any group (semi-sitting, p = 0.967; supine, p = 0.193). CONCLUSIONS: Although SEP amplitude reductions were associated with large subdural air collections, this was not observed in the subset of patients with SEP attenuation and for the MEP monitoring, suggesting other pathophysiological mechanisms, such as brain shift, for the artificial amplitude reduction.

Spinal metastasis of endometrial stromal sarcoma: clinicopathological features and management.

BACKGROUND: Endometrial Stromal Sarcoma (ESS) is a rare uterine malignancy which often metastasizes several years after initial diagnosis. Thoracic spine is a rare ESS metastatic site and its proper management is still not a consensus. We discuss the histopathological features and the management strategies through an illustrative case of a 77 year-old woman with metastasis to the thoracic spine 13 years after total hysterectomy for ESS. METHODS: Review of the literature and identification of 5 patients, including our present case, with ESS involving the spinal cord. We discuss the outcomes achieved after each therapy. In our case, the patient presented a mass involving the thoracic spinal canal constricting the spinal cord at T7 level. A two-level decompression laminectomy was performed and the lesion was partially excised. RESULTS: The histopathological along with the immunohistochemical profile mitotic rate indicated the endometrial stromal cells origin of the tumor, confirming the diagnosis of a low-grade ESS metastasis. The patient was managed with surgery in combination with postoperative radiation therapy. CONCLUSIONS: The small number of published cases precludes definitive conclusions regarding standard management. However, it seems that treatment of metastatic ESS to the spine matches the same general concepts of spine metastasis, namely surgery followed by radiation therapy, due to clinical improvement and long-term disease control of the reported cases. Hormonal therapy may be considered in recurrent disease with strong expression of estrogen and progesterone receptors. However, these findings need confirmation in larger studies.

The role of the trigeminocardiac reflex in postoperative hearing function in non-vestibular schwannoma cerebellopontine angle tumors.

The trigeminocardiac reflex (TCR) is a common event during skull base surgery that can lead to intraoperative arterial hypotension and bradycardia. Arterial hypotension associated with TCR can be a negative prognostic factor for postoperative auditory function and ipsilateral tinnitus in patients undergoing surgery for vestibular schwannoma (VS). In this study, the contribution of TCR to postoperative auditory function in non-VS cerebellopontine angle (CPA) tumor surgery was investigated. From a consecutive series of 102 patients with CPA tumors, we studied the occurrence of TCR and its influence on postoperative auditory function in patients with non-VS tumors. Pre- and postoperative auditory function, pre- and intraoperative mean arterial blood pressure, as well as preoperative medication, tumor size, and occurrence of TCR were evaluated. Of the 35 patients evaluated, four developed intraoperative TCR, of whom one was preoperatively deaf. Preoperative functional hearing was detected in 30/35 patients (85.7%): preoperative deafness was documented in one patient in the TCR group and in four patients in the non-TCR group. Of the 30 patients with preoperative functional hearing, 1/3 (33.3%) patients in the TCR group and 23/27 (85.2%) patients in the non-TCR group had functional hearing postoperatively. When patients with large tumors and functional, hearing were considered, only 33.3% of patients in the TCR group and 77.8% of patients in the non-TCR group remained within the same hearing classes following surgical treatment (p=0.1573). TCR may be a negative prognostic factor for postoperative auditory function in patients with large, non-VS CPA tumors.

The parahippocampal gyrus as a multimodal association area in psychosis.

Temporal lobe lesions may lead to schizophrenia-like psychosis, a phenomenon resembling psychotic disorders such as schizophrenia. We discuss a patient with a temporo-basal low-grade glioma presenting with bimodal hallucinosis (visual and auditory), a symptom set that is rarely described in psychotic disorders associated with morphological correlates. In light of a literature review of patients experiencing similar bimodal psychotic symptoms and electrophysiological data obtained in non-human primates, we suggest the parahippocampal gyrus to be a multimodal association area with bimodal units.

Intraoperative brainstem auditory evoked potential observations after trigeminocardiac reflex during cerebellopontine angle surgery.

BACKGROUND: The occurrence of trigeminocardiac reflex (TCR) is known to be a negative prognostic factor for hearing preservation in cerebellopontine angle tumor surgery. Our study was conducted to investigate brainstem auditory evoked potential (BAEP) changes after this reflex in cerebellopontine angle tumor surgery and to evaluate their impact on postoperative hearing function. METHODS: Five of 102 consecutive patients had an intraoperative TCR (4.9%) and were retrospectively evaluated for the intraoperative BAEP changes after TCR and postoperative auditory function (7 to 10 d after surgery). One of the 5 patients was preoperatively deaf and therefore excluded from this analysis. RESULTS: Four patients with preoperative functional hearing developed one or more episodes of TCR. Intraoperative BAEP was maintained in 1 patient, whereas in 3 cases an acute intraoperative BAEP deterioration occurred within 2:04 to 3:27 minutes (mean 2:44 min) after TCR with increased wave latency, decreased wave amplitude, and even wave loss. Two patients had deteriorated BAEP waves until the surgical completion and were postoperatively deaf. CONCLUSIONS: Although no direct cause-effect relationship has yet been shown, we suggest TCR as an additional event that may cause BAEP changes. The observed BAEP alterations occurred minutes rather than seconds after the TCR incident leading to both temporary and permanent wave deterioration. This association of BAEP deterioration and TCR occurrence, however, remains yet to be proven justifying further study in the field.

Transcranial electrocortical stimulation to monitor the facial nerve motor function during cerebellopontine angle surgery.

OBJECTIVE: This study was conducted to investigate the success rate of using the facial motor evoked potential (FMEP) of orbicularis oculi and oris muscles for facial nerve function monitoring with use of a stepwise protocol, and its usefulness in predicting facial nerve outcome during cerebellopontine angle (CPA) surgeries. METHODS: FMEPs were recorded intraoperatively from 60 patients undergoing CPA surgeries. Transcranial electrocortical stimulation (TES) was performed using corkscrew electrodes positioned at hemispheric montage (C3/C4 and CZ). The contralateral abductor pollicis brevis muscle was used as the control response. Stimulation was always applied contralaterally to the affected side using 1, 3, or 5 rectangular pulses ranging from 200 to 600 V with 50 micros of pulse duration and an interstimulus interval of 2 ms. Facial potentials were recorded from needles placed in the orbicularis oculi and oris muscles. RESULTS: FMEP from the orbicularis oris and oculi muscles could be reliably monitored in 86.7% and 85% of the patients, respectively. The immediate postoperative facial function correlated significantly with the FMEP ratio in the orbicularis oculi muscle at 80% amplitude ratio (P = .037) and orbicularis oris muscle at 35% ratio (P = .000). FMEP loss was always related to postoperative facial paresis, although in different degrees. CONCLUSION: FMEPs can be obtained reliably by using TES with 3 to 5 train pulses. Stable intraoperative FMEPs can predict a good postoperative outcome of facial function. However, further refinements of this technique are necessary to minimize artifacts and to make this method more reliable.