Tools and resources for neuroanatomy education: a systematic review.

BACKGROUND: The aim of this review was to identify studies exploring neuroanatomy teaching tools and their impact in learning, as a basis towards the implementation of a neuroanatomy program in the context of a curricular reform in medical education. METHODS: Computer-assisted searches were conducted through March 2017 in the PubMed, Web of Science, Medline, Current Contents Connect, KCI and Scielo Citation Index databases. Four sets of keywords were used, combining "neuroanatomy" with "education", "teaching", "learning" and "student*". Studies were reviewed independently by two readers, and data collected were confirmed by a third reader. RESULTS: Of the 214 studies identified, 29 studies reported data on the impact of using specific neuroanatomy teaching tools. Most of them (83%) were published in the last 8 years and were conducted in the United States of America (65.52%). Regarding the participants, medical students were the most studied sample (37.93%) and the majority of the studies (65.52%) had less than 100 participants. Approximately half of the studies included in this review used digital teaching tools (e.g., 3D computer neuroanatomy models), whereas the remaining used non-digital learning tools (e.g., 3D physical models). CONCLUSIONS: Our work highlight the progressive interest in the study of neuroanatomy teaching tools over the last years, as evidenced from the number of publications and highlight the need to consider new tools, coping with technological development in medical education.

Sacral malformations: use of imaging to optimise sacral nerve stimulation.

INTRODUCTION: The success of sacral nerve stimulation, a common treatment for pelvic floor disorders, depends on correct placement of the electrodes through the sacral foramina. When the bony anatomy and topography of the sacrum and sacral spinal nerves are intact, this is easily achieved; where sacral anomalies exist, it can be challenging. A better understanding of common sacral malformations can improve the success of sacral nerve stimulation (SNS) electrode placement. MATERIAL AND METHODS: We reviewed 998 consecutive MRI scans performed to investigate low back pain in patients who had undergone CT and/or X-ray. RESULTS: Congenital sacral malformations were found in 24.1%, the most common being sacral meningeal cysts (16%) and spina bifida occulta (9.9%). Others were lumbosacral transitional vertebrae (2.5%), anterior occult meningocele (0.5%), partial sacral agenesis (0.2%) and vertebral dysplasia of S1 (0.2%). CONCLUSION: This radiologic review uncovered a high incidence of sacral malformations, and most were asymptomatic. All surgeons who perform SNS should have a basic understanding of sacral malformations, their incidence and effect on foraminal anatomy. Imaging will aid procedural planning.

Surface anatomical landmarks for the location of posterior sacral foramina in sacral nerve stimulation.

BACKGROUND: Sacral nerve stimulation is a common treatment for various pelvic floor disorders. It consists of the percutaneous introduction of electrodes through the posterior sacral foramina for therapeutic stimulation of the target sacral spinal nerve. The aim of our study was to determine the surface anatomical landmarks of the sacrum to facilitate identification of the posterior sacral foramina. METHODS: This study was conducted on 20 human cadavers. The cadavers were placed in a prone position, and all the soft tissues of the sacral region were removed to allow exposure of the osseous structures. Different measurements were taken in relation to the posterior sacral foramina, the posterior superior iliac spine (PSIS) and the median sacral crest (MSC). A median coefficient of variation (CV) was determined. RESULTS: The diameter of the second sacral foramen showed the greatest variability. The distances between each individual foramen and the MSC had an acceptable variability (CV < 20%). In contrast, the distance between foramina had a high variability. The distance between PSIS and the second posterior sacral foramen was also found to have an acceptable variability (CV < 20%). However, the angle formed by an horizontal line between PSIS and a line between PSIS and S2 foramina had high variability. CONCLUSIONS: We found that the distance between sacral foramina and MSC is relatively constant while the distance between foramina and the relations between foramina and PSIS is highly variable. Detailed knowledge of the anatomy may facilitate electrode placement and is complementary to the regular use of fluoroscopy.

Comprehensive review of extraventricular neurocytoma with report of two cases, and comparison with central neurocytoma.

Two new cases of extraventricular neurocytoma are reported. The first concerns an 18-year-old female with a left frontal lobe lesion and the second occurred in a 54-year-old female in the thoracic spinal cord. The first patient is free of disease after 18 months of follow up. The second patient is stable after 16 months of follow up. Both were operated - total excision in Case 1 and partial resection in Case 2. The latter underwent adjuvant radiotherapy due to atypical histological features. Cases of extraventricular neurocytoma are reviewed. Differences and similarities between extraventricular and central neurocytoma are outlined.

Hydrocephalus caused by a venous varix.

INTRODUCTION: Vascular malformations are uncommon causes of aqueductal obstruction. To our concern, only one case of hydrocephalus caused by a venous varix draining an unruptured arteriovenous malformation has been described in the literature. CASE REPORT: We report the case of a 70-year-old woman presenting with progressive cognitive impairment, gait disturbance and urinary incontinence. Magnetic resonance imaging and magnetic resonance angiography revealed a large venous varix draining an unruptured arteriovenous malformation causing hydrocephalus. CONCLUSION: Although uncommon, it is necessary to consider the presence of a vascular malformation in adults who presented with signs of aqueductal obstruction.

[Atypical presentation of intramedullary sarcoidosis: report of two cases]. / Presentación atípica de sarcoidosis intramedular: a propósito de dos casos.

INTRODUCTION: Neurological involvement in sarcoidosis occurs in 5 to 15% of cases, but medullary involvement is very uncommon. CASE REPORT: We report two cases of sarcoidosis with medullary involvement as an initial presentation. Case 1: a 41 year-old man presented with a four-month history of lumbar pain, gait and sphincter disturbances; examination revealed a spastic paraparesis, hyperreflexia and a sensory level by D4-D6. Serum angiotensin converting enzyme (SACE) was normal. Magnetic resonance image (MRI) showed diffuse spinal cord enlargement with hyperintensity signal between D4-D5 and D10-11, with contrast enhancement. Spinal biopsy was consistent with sarcoidosis. Case 2: a 36 year-old man presented with a two-months history of gait difficulties and two episodes of blurred vision on his left eye that improved with topical therapy. Examination revealed lupus pernio in the ears and a spastic hyperreflexic paraparesis. Laboratory detected increased SACE. MRI showed focal spinal cord areas of hyperintensity at cervico-dorsal levels with contrast enhancement. Ear biopsy was consistent with sarcoidosis. Clinical courses under corticosteroids were favourable in both cases. CONCLUSION: Intramedullary lesions are infrequently the first manifestation of sarcoidosis especially when there is no systemic involvement (case 1). It is also rare in association with lupus pernio and ocular involvement (case 2). In the later (with systemic manifestations) SACE was raised. Biopsy is very useful for early diagnosis.

Lipid peroxidation in nicotinamide-deficient and nicotinamide-supplemented rats with streptozotocin-induced diabetes.

Reactive oxygen species have been related to the pathogenesis of various diseases, including diabetes mellitus. Nicotinamide has been used for the prevention of the diabetogenic effects of streptozotocin (STZ) in animals. In the present study we assessed the effect of diets with deficient, normal or 17-fold supplemented nicotinamide concentrations on the rate of lipoperoxidation in animals with STZ-induced diabetes. Male Wistar rats were divided into three groups kept on one of the diets for six weeks: DD, diabetic rats on a nicotinamide-deficient diet; DN, diabetic rats on a normal nicotinamide diet; and DS, diabetic rats on a nicotinamide-supplemented diet. During the fourth week of the experiment all animals were fasted for 24 hours and injected into the tail vein with a single STZ dose (40 mg/kg weight). Eight animals from each of the six groups were then sacrificed 24 hours, 1 week and 2 weeks after STZ injection. Mean pancreatic thiobarbituric acid reactive substances (TBARS) (nmol/mg tissue) were significantly lower in the DS group (p < 0.05) compared to the DN and DD groups at 24 hours and during the first week. Hepatic TBARS concentrations (nmol/mg protein) did not differ between groups. Mean hepatic reduced glutathione (GSH) levels were significantly higher (46.76 +/- 12.33 nmol/mg protein) in the DS group compared to the DD (32.90 +/- 6.70) and DN (24.55 +/- 6.41) groups, but only after the 24-hour period. Hepatic vitamin E consumption (microgram/g tissue) was considerable in the groups not supplemented with nicotinamide, whereas vitamin E levels were unchanged in the supplemented group. In contrast, plasma vitamin E levels were decreased in the normal and supplemented groups after 1 and 2 weeks. A higher N-methylnicotinamide excretion (microgram/24 hours) occurred in the supplemented group. We conclude that, after induction of diabetes with STZ, nicotinamide supplementation protected from the damage caused by the toxic action of STZ, promoting lower lipid peroxidation.

Solitary fibrous tumor of the thoracic spine.

Intraspinal solitary fibrous tumors are rare: to our knowledge, the literature reports only 27 cases. We present a histologically and immunohistochemically confirmed solitary fibrous tumor involving the intradural extramedullary compartment of the thoracic spine. Microsurgical gross-total resection was achieved. A definitive role for adjuvant treatments in this type of tumor has not been established and therefore, they were not used. The patient was well, without clinical or radiological recurrence, 18 months after surgery.

[Hemifacial spasms and vertebral dolichoectasias]. / Espasmos hemifaciales y dolicoectasias de las arterias vertebrales.

INTRODUCTION: Hemifacial spasm (HFS) is characterized by chronic twitching or spasm of one side of the face. It affects muscles activated by the facial nerve. HFS is believed to result from irritation of the facial nerve at its exit from the brainstem and most cases are associated with a small vascular loop compression. Rarely it is associated with a vertebral artery dolichoectasia. CASE REPORTS: We report three cases of HFS whose magnetic resonance imaging and magnetic resonance angiography revealed vertebral dolichoectatic arteries compressing the facial nerve and causing HFS. These cases were selected from the group of patients of the dystonic outpatient clinics, Neurology Department, between April 1st 1998 and December 30th 2007. CONCLUSIONS: Magnetic resonance imaging and magnetic resonance angiography are essential for the diagnosis of a vertebral dolichoectasia and should be considered the initial screening procedures in the assessment of patients with HFS. The role of these neuroradiologic studies in the diagnosis of HFS is not only to detect the vascular structures running adjacent to the root exit zone that might distort the facial nerve and compress the brain stem around the root exit zone, but also to exclude other causes in a single non-invasive examination.

Comparative efficacy of fluconazole and amphotericin B in the parenteral treatment of experimental paracoccidioidomycosis in the rat.

Patients with severe and complicated paracoccidioidomycosis are treated with amphotericin B by the intravenous route. Fluconazole is active in vitro against Paracoccidioides brasiliensis and can also be administered intravenously, but few clinical or experimental data are available about its action against the infection caused by this fungus. In the present study, the efficacy of fluconazole and amphotericin B was assessed comparatively in rats inoculated parenterally with P. brasiliensis. The treatment was performed 3 times a week for 4 weeks starting one week after infection. Fluconazole administered intraperitoneally (14 mg/kg body weight/dose) was more effective (P < 0.001) than amphotericin B (2 mg/kg body weight/dose) in reducing the number of colony forming units in the lungs and spleen. When administered intravenously at the dose of 3 mg/kg body weight, fluconazole was as effective as amphotericin B (0.8 mg/kg body weight) in reducing the pulmonary fungal burden. Under these conditions, the rats treated with fluconazole had a smaller number of colony forming units than untreated animals (P < 0.001), but amphotericin B was more effective than fluconazole in reducing spleen infection (P < 0.005). Except for this result obtained with a low dose, fluconazole showed an antifungal action equal to or higher than that of amphotericin B. The activity of fluconazole at doses equivalent to those used for human treatment suggests that this antifungal agent may be an alternative to amphotericin B for the early intravenous treatment of patients with paracoccidioidomycosis.

Bacteriological status (point prevalence) of lepromatous outpatients under sulfone treatment.

The study concerns 337 outpatients with lepromatous leprosy who had been receiving dapsone treatment for 1-26 years-69% of them regularly and 31% irregularly. Routine bacterial examination (10 min per slide) by a paramedical technician showed only 50% of these patients to be bacteriologically positive. This rate attained 99% when each slide was examined for 30-60 min by a qualified bacteriologist. Other factors-apart from the limited action of sulfones-might account for these unexpected results: the material was collected by an experienced leprologist; the disease was still clinically active in 75% of the patients; about 25% of them had been treated for only 1-4 years; and the intake of dapsone in long-term treatment gradually decreases.

Espasmos hemifaciales y dolicoectasias de las arterias vertebrales / Hemifacial spams and vertebral dolichoectasias

Introducción. El espasmo hemifacial (EHF) se caracteriza por el espasmo o fasciculaciones crónicas de un lado dela cara. Afecta a los músculos activados por el nervio facial. Se cree que el EHF se deriva de la irritación del nervio facial en su salida del tronco encefálico y, en la mayoría de casos, está vinculado a una pequeña compresión por un asa vascular. En raras ocasiones, está asociado a una dolicoectasia de la arteria vertebral. Casos clínicos. Presentamos tres casos de EHF enlos cuales los resultados de una resonancia magnética y de una angiorresonancia pusieron de manifiesto dolicoectasia de las arterias vertebrales que comprimían el nervio facial y provocaban EHF. Estos casos se seleccionaron del grupo de pacientes tratados en las consultas externas para los trastornos distónicos, en el Servicio de Neurología, entre el 1 de abril de 1998 y el30 de diciembre de 2007. Conclusiones. La resonancia magnética y la angiorresonancia son fundamentales para el diagnósticode una dolicoectasia de la arteria vertebral, y deben considerarse como los procedimientos iniciales de detección sistemática en la evaluación de los pacientes con EHF. El papel de estos estudios neurorradiológicos en el diagnóstico del EHF no es sólo detectar las estructuras vasculares con una trayectoria próxima a la zona de salida de la raíz, que podrían deformarel nervio facial y comprimir el tronco encefálico alrededor de la zona de salida de la raíz, sino también excluir otras causas en una única exploración no invasiva

Introduction. Hemifacial spasm (HFS) is characterized by chronic twitching or spasm of one side of the face. Itaffects muscles activated by the facial nerve. HFS is believed to result from irritation of the facial nerve at its exit from the brainstem and most cases are associated with a small vascular loop compression. Rarely it is associated with a vertebral artery dolichoectasia. Case reports.We report three cases of HFS whose magnetic resonance imaging and magnetic resonanceangiography revealed vertebral dolichoectatic arteries compressing the facial nerve and causing HFS. These cases were selected from the group of patients of the dystonic outpatient clinics, Neurology Department, between April 1st 1998 and December 30th 2007. Conclusions. Magnetic resonance imaging and magnetic resonance angiography are essential for thediagnosis of a vertebral dolichoectasia and should be considered the initial screening procedures in the assessment of patients with HFS. The role of these neuroradiologic studies in the diagnosis of HFS is not only to detect the vascular structures running adjacent to the root exit zone that might distort the facial nerve and compress the brain stem around the root exit zone, but also to exclude other causes in a single non-invasive examination