Preoperative tractography algorithm for safe resection of tumors located in the descending motor pathways zone.

Background: Diffusion tensor imaging (DTI) tractography facilitates maximal safe resection and optimizes planning to avoid injury during subcortical dissection along descending motor pathways (DMPs). We provide an affordable, safe, and timely algorithm for preoperative DTI motor reconstruction for gliomas adjacent to DMPs. Methods: Preoperative DTI reconstructions were extracted from a prospectively acquired registry of glioma resections adjacent to DMPs. The surgeries were performed over a 7-year period. Demographic, clinical, and radiographic data were extracted from patients' electronic medical records. Results: Nineteen patients (12 male) underwent preoperative tractography between January 1, 2013, and May 31, 2020. The average age was 44.5 years (range, 19-81 years). A complete radiological resection was achieved in nine patients, a subtotal resection in five, a partial resection in three, and a biopsy in two. Histopathological diagnoses included 10 patients with high-grade glioma and nine with low-grade glioma. A total of 16 perirolandic locations (10 frontal and six frontoparietal) were recorded, as well as two in the insula and one in the basal ganglia. In 9 patients (47.3%), the lesion was in the dominant hemisphere. The median preoperative and postoperative Karnofsky Performance Scores were 78 and 80, respectively. Motor function was unchanged or improved over time in 15 cases (78.9%). Conclusion: This protocol of DTI reconstruction for glioma removal near the DMP shows good results in low-term neurological functional outcomes.

Anterior cerebral artery trifurcation with infraoptic origin and contralateral A1 segment absence.

PURPOSE: To describe an uncommon anatomical variant of the anterior cerebral artery and the imaging findings. METHODS: A 2-month-old infant with known history of atrial and ventricular septal defects was admitted to our institution for evaluation and management of growth failure. Given the clinical presentation and medical history, magnetic resonance imaging (MRI) of the brain and MR angiography (MRA) were performed to exclude congenital hypopituitarism and any vascular abnormality. RESULTS: Time of flight MRA revealed trifurcation of the anterior cerebral artery with one of the vessels arising from the ophthalmic segment of the right internal carotid artery; thus, the A1 segment of the left anterior cerebral artery (ACA) was absent, and the right posterior cerebral artery (PCA) had a fetal origin. CONCLUSION: Anatomical variants of the cerebral circulation are asymptomatic and found incidentally. Knowledge of these variants and careful examination of CT/MRI angiograms are important for diagnosis and treatment planning.

Structural and functional connectivity of the ascending arousal network for prediction of outcome in patients with acute disorders of consciousness.

To determine the role of early acquisition of blood oxygen level-dependent (BOLD) signals and diffusion tensor imaging (DTI) for analysis of the connectivity of the ascending arousal network (AAN) in predicting neurological outcomes after acute traumatic brain injury (TBI), cardiopulmonary arrest (CPA), or stroke. A prospective analysis of 50 comatose patients was performed during their ICU stay. Image processing was conducted to assess structural and functional connectivity of the AAN. Outcomes were evaluated after 3 and 6 months. Nineteen patients (38%) had stroke, 18 (36%) CPA, and 13 (26%) TBI. Twenty-three patients were comatose (44%), 11 were in a minimally conscious state (20%), and 16 had unresponsive wakefulness syndrome (32%). Univariate analysis demonstrated that measurements of diffusivity, functional connectivity, and numbers of fibers in the gray matter, white matter, whole brain, midbrain reticular formation, and pontis oralis nucleus may serve as predictive biomarkers of outcome depending on the diagnosis. Multivariate analysis demonstrated a correlation of the predicted value and the real outcome for each separate diagnosis and for all the etiologies together. Findings suggest that the above imaging biomarkers may have a predictive role for the outcome of comatose patients after acute TBI, CPA, or stroke.

Establishing an acquisition and processing protocol for resting state networks with a 1.5 T scanner: A case series in a middle-income country.

OBJECTIVE: The aim of this study was to characterize the capability of detection of the resting state networks (RSNs) with functional magnetic resonance imaging (fMRI) in healthy subjects using a 1.5T scanner in a middle-income country. MATERIALS AND METHODS: Ten subjects underwent a complete blood-oxygen-level dependent imaging (BOLD) acquisition on a 1.5T scanner. For the imaging analysis, we used the spatial independent component analysis (sICA). We designed a computer tool for 1.5 T (or above) scanners for imaging processing. We used it to separate and delineate the different components of the RSNs of the BOLD signal. The sICA was also used to differentiate the RSNs from noise artifact generated by breathing and cardiac cycles. RESULTS: For each subject, 20 independent components (IC) were computed from the sICA (a total of 200 ICs). From these ICs, a spatial pattern consistent with RSNs was identified in 161 (80.5%). From the 161, 131 (65.5%) were fit for study. The networks that were found in all subjects were: the default mode network, the right executive control network, the medial visual network, and the cerebellar network. In 90% of the subjects, the left executive control network and the sensory/motor network were observed. The occipital visual network was present in 80% of the subjects. In 39 (19.5%) of the images, no any neural network was identified. CONCLUSIONS: Reproduction and differentiation of the most representative RSNs was achieved using a 1.5T scanner acquisitions and sICA processing of BOLD imaging in healthy subjects.

Neuroanatomía funcional de la escala de coma de Glasgow / Functional neuroanatomy of the Glasgow coma scale

Introducción: La escala de coma de Glasgow (ECG) es una escala mundialmente reconocida para la clasificación de pacientes con trauma craneoencefálico de acuerdo a su compromiso neurológico. Esta escala evalúa la apertura ocular, la respuesta verbal y la respuesta motora. La neuroanatomía funcional representa un compromiso secuencial para el descenso en el puntaje de cada uno de estos ítems. El objetivo de esta revisión es describir la anatomía del sistema reticular activador ascendente (SRAA), la anatomía funcional del lenguaje, la anatomía del tallo cerebral y de las vías motoras que representan cada ítem evaluado por la ECG. Materiales y métodos: Se hizo una revisión narrativa bibliográfica de las principales vías para cada ítem de la ECG. Resultados: Las principales vías en relación con la apertura ocular se concentran en las vías del SRAA, las vías de la respuesta verbal incluyen las vías del lenguaje y las vías que provienen del putamen y del cerebelo que regulan la emisión del lenguaje, mientras que las vías que regulan la respuesta motora principalmente se relacionan con la vía piramidal, el sistema rubro-espinal y vestíbulo-espinal. Conclusiones: El descenso del puntaje en los tres ítems que evalúa la ECG se relacionan con vías específicas que predominan en los ganglios basales y en el tallo cerebral.

Introduction: The Glasgow Coma Scale (GCS) is a globally recognized scale for the classification of patients with traumatic brain injury according to their neurological impairment. This scale evaluates the ocular opening, the verbal response and the motor response. Functional neuroanatomy represents a sequential decrease in the score of each of these items. The objective of this review is to describe the anatomy of the ascending reticular activating system (ARAS), the functional anatomy of the language, and the anatomy of the brainstem and the motor pathways that represent each item evaluated by the GCS. Materials and methods: A narrative literature review of the main routes for each item of the scale was performed. Results: The main pathways in relation to the ocular opening are concentrated in the ARAS, the verbal response pathways include the language pathways and the connections that come from the putamen and the cerebellum that regulate the production of the language, while the pathways that regulate the motor response mainly relate to the pyramidal tract, the rubro-spinal and vestibulo-spinal systems. Conclusions: The decline of the score in the three items that evaluates the GCS is related to specific pathways that predominate in the basal ganglia and in the brainstem.

Structural and functional connectivity of ascending reticular activating system in a patient with impaired consciousness after a cardiac arrest: A case report.

RATIONALE: Diffusion tensor imaging (DTI), diffusion tensor tractography (DTT), as well as resting-state-functional magnetic resonance imaging (rsfMRI) are promising methods for assessing patients with disorders of consciousness (DOCs). PATIENT CONCERNS: This work describes the main findings using DTI, DTT, and rsfMRI in a patient with a DOC secondary to an anoxic encephalopathy who had a fatal outcome. She was an 85-year-old woman who presented a cardiac arrest and underwent cardiopulmonary resuscitation for 20 minutes then returning to spontaneous circulation. After sedation withdrawal, 2 days after the event, she remained with a Glasgow Coma Scale score of 3/15 and with an absence of brainstem reflexes. DIAGNOSES: DOC secondary to an anoxic encephalopathy after cardiovascular resuscitation. INTERVENTIONS: A complete brain MRI scan was performed 72 hours after the initial event, including DTI, DTT, and rsfMRI. DTT demonstrated disruption of both ventral and dorsal tegmental tracts bilaterally. DTI showed a reduction of fractional anisotropic level in the mesencephalic nuclei. Moreover, changes in the number of fiber tracts were not evidenced in any portions of the ascending reticular activating system (ARAS). Finally, an increase in the anticorrelated and correlated association among the nuclei in the ARAS and the cortex was evidenced. OUTCOMES: Patient deceased. LESSONS: Neuroimaging demonstrated low FA values in the ARAS, destruction of dorsal and ventral tegmental tracts, as well as hyper-connective (highly correlated or anti-correlated) association among ARAS and cortical nuclei compared with 3 healthy control subjects.

Identification of Preoperative Language Tracts for Intrinsic Frontotemporal Diseases: A Pilot Reconstruction Algorithm in a Middle-Income Country.

OBJECTIVE: Diffusion tensor imaging (DTI) tractography provides useful information that can be used to optimize surgical planning and help avoid injury during subcortical dissection of eloquent tracts. The objective is to provide a safe, timely, and affordable algorithm for preoperative DTI language reconstruction for intrinsic frontotemporal diseases. METHODS: We reviewed a prospectively acquired database of preoperative DTI reconstruction for resection of left frontotemporal lesions over 3 years at Hospital de San José and Hospital Infantil Universitario San José, Fundación Universitaria de Ciencias de la Salud, Bogota, Colombia. Preoperative and postoperative clinical and radiographic features were determined from retrospective chart review. A comprehensive review of the structural and functional anatomy of the language tracts was performed. Separate reconstruction of both ventral (semantic) and dorsal (phonologic) stream pathways is described: arcuate fasciculus, superior longitudinal fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, and inferior longitudinal fasciculus. RESULTS: Between January 2015 and January 2018, 44 tumor cases were found to be resected with preoperative fiber tracking planning and neuronavigation-guided surgery. Ten patients (7 women, 3 men) aged 28-65 years underwent resection of an intrinsic frontotemporal lesion with preoperative DTI tractography reconstruction of language tracts. Eight cases (80%) were high-grade gliomas and 2 (20%) were cavernous malformations. In 5 cases (50%), the lesion was in the frontal lobe and in 5 (50%), it was in the temporal lobe. The extent of resection was classified as gross total resection (100%), subtotal resection (>90%), or partial resection (<90%). Gross total resection was achieved in 5 cases (50%), subtotal resection was achieved in 4 cases (40%), and partial resection in the remaining case (10%). Compromised tracts included superior longitudinal fasciculus in 7 (70%), inferior longitudinal fasciculus in 4 (40%), the arcuate fasciculus in 3 (30%), and uncinate fasciculus in 1 (10%). Language function was unchanged or improved in 90% of patients. New-onset postoperative language decline occurred in 1 patient, who recovered transient phonemic paraphasias 1 month after resection. The mean follow-up time was 7 months (range, 4-12 months). Residual tumors were treated with radiation and/or with chemotherapy as indicated in an outpatient setting. CONCLUSIONS: We present a safe and efficacious preoperative DTI language reconstruction algorithm that could be used as a feasible treatment strategy in a challenging subset of tumors in low- to middle-income countries.

Recovery of consciousness after a brainstem cavernous malformation hemorrhage: A descriptive study of preserved reticular activating system with tractography.

The aim of this study is to describe the imaging features, the relevant anatomy, and the fractional anisotropy (FA) values in diffusion tensor tractography (DTT) of the ascending reticular activating system (ARAS) fiber tracts in 2 patients who recovered from initial altered consciousness after presenting with a brainstem cavernous malformation (BSCM) hemorrhage. A DTT was performed in 2 patients with impaired consciousness after a brainstem cavernous malformation hemorrhage. A 1.5 T scanner was used to obtain the axial tensors. Post-processing was performed and the mean FA values were recorded. The FA maps were used to seed the following regions of interest: the ventromedial midbrain, the anterior thalamus bilaterally, and the hypothalamus bilaterally. The first case presented with posterior displacement of the dorsal raphè fiber tracts, with preservation of all the ascending reticular activating fiber tracts and spontaneous recovery of consciousness after 20 days. The second case presented with no destruction but also had posterior displacement of the inferior dorsal raphè fiber tracts, with recovery of consciousness 1 month after resection surgery. Described in this study are affected fibers of the ARAS, as well as the FA value abnormalities in 2 patients, with recovery of a transient disorder of consciousness after a BSCM hemorrhage.

Principios de tractografía cerebral / Principles of brain tractography

Objetivo: hacer una revisión de los principales tractos cerebrales y sus aplicaciones en las neurociencias a partir de la experiencia en la Fundación Universitaria de Ciencias de la Salud (FUCS), Bogotá D.C., Colombia. Materiales y métodos: revisión bibliográfica y utilización de imágenes con resonadores de 1.5 T o 3 T para describir las imágenes de tractografía en enfermedades del sistema nervioso central. Resultados: se muestran las características principales de la tractografía basados en casos de nuestra institución. Discusión: en la gran mayoría de patologías cerebrales no hay estudios sobre la utilidad de la tractografía. Aunque es un estudio disponible en la actualidad, es poca la información que suele obtenerse a nivel clínico, pues toma bastante tiempo el pos proceso de las imágenes y en la mayoría de centros no está protocolizada la secuencia de obtención de la reconstrucción de cada uno de los tractos por separado. Conclusiones: es posible reconstruir los principales tractos cerebrales con escáneres de 1.5 T y 3 T, identificando las vías clave del cerebro y su relación con tumores cerebrales, trauma craneoencefálico, abuso de sustancias y otras afecciones.

Objective: to present the basic mathematical, physical and radiological principles behind tractography, as well as, providing a review of the main tracts in the brain and their applications in neuroscience from the Fundación Universitaria de Ciencias de la Salud (FUCS) in Bogota D.C., Colombia experience. Materials and Methods: bibliographic review and use of a 1.5 T or 3T MR imaging system to describe tractography images in central nervous system disorders. Results: the main features of tractography are shown based on cases at our institution. Discussion: there are no identified studies on the usefulness of tractography in the vast majority of brain related pathologies. Although this procedure is currently available, clinical information is scarce, as the image-processing techniques are lengthy and in most institutions, protocols have not been determined to reconstruct each of the tracts in the brain. Conclusions: it is possible to reconstruct brain tracts using 1.5T and 3T scanners, identifying the major brain tracts and their relationship with brain tumors, cranioencephalic trauma, substance abuse and other conditions.

Síndrome neuroléptico maligno con mielinolisis central pontina / Neuroleptic malignant syndrome with central pontine myelinolysis

RESUMEN El síndrome neuroléptico maligno (SNM) es una complicación severa de los antipsicóticos, en especial los de primera generación como el haloperidol, que fue el primero en el que se describió esta patología, caracterizada por fiebre, rigidez, alteración del estado de conciencia y disautonomías. Por otro lado, la mielinólisis central pontina (ahora llamada síndrome de desmielinización osmótica) resulta de las alteraciones agudas séricas del sodio, como las que ocurren en las reposiciones de hiponatremia, y podría poner en riesgo la vida al igual que el SNM. La asociación de estas dos patologías es inusual y hasta el momento no se conoce con claridad su relación causal, producto de los pocos casos reportados. Aunque se conoce la mortalidad del síndrome neuroléptico maligno, la compañía de la mielinolisis central pontina podría aumentar la morbimortalidad de esta entidad, por lo cual es necesario reconocerla rápidamente para prevenir la aparición de complicaciones, ya que no cuenta con un tratamiento específico. Presentamos el caso de un paciente joven que cursó con estas dos patologías, y consideramos que la causa de la mielinolisis central pontina fue el haloperidol, así como del SNM. A pesar de ello, este medicamento continúa siendo muy seguro en la práctica clínica ya que la aparición de estas complicaciones es una reacción idiosincrática por algún tipo de susceptibilidad genética desconocida.

SUMMARY Neuroleptic malignant syndrome (NMS) is a severe complication of antipsychotics, especially those of first generation such as haloperidol, which was the first in which this pathology was described, characterized by: fever, rigidity, alteration of the state of consciousness and dysautonomies. On the other side, central pontine myelinolysis (Now Called Osmotic Demyelination Syndrome), search results of acute sodium alterations of sodium, as those occurring in hyponatremia replenings and could put life at risk just like the NMS. The association of these two pathologies is unusual and until now, their causal relationship, the result of the few cases reported, is not clearly known. Although the relationship of the neurological syndrome may be limited, the company of central myelolysis could increase the morbidity of this entity, so it is necessary to be required quickly to prevent the onset of complications, which does not have a specific treatment. We present the case of a young patient who has these pathologies and we consider that the cause of centralized myelinolysis is haloperidol as well as NMS, despite this, this medication continues to be very safe in clinical practice since the appearance of These complications is an idiosyncratic reaction due to some type of unknown genetic susceptibility.

Descripción de cambios en la difusibilidad media en resonancia magnética por lesiones del sistema reticular activador ascendente en pacientes adultos con trauma craneoencefálico y alteración del estado de conciencia / Description of changes in mean diffusivity in magnetic resonance of injuries of the ascending reticular system in patients with traumatic brain injury and impaired consciousness

RESUMEN INTRODUCCIÓN: Los pacientes con trauma craneoencefálico severo pueden tener secuelas neurológicas graves que generan discapacidad de rangos diferentes según la escala de Barthel. La alteración del estado de consciencia es la secuela más grave y es causa de dependencia completa de estos pacientes por la pérdida del autocuidado. La relación entre los hallazgos anormales en las neuroimágenes y los diferentes estados de conciencia ha sido objeto de investigación en los últimos años, con la posibilidad de que existan nuevas opciones con el posproceso de imágenes obtenidas por resonancia magnética nuclear. Este estudio pretende describir las alteraciones en la difusibilidad media haciendo posproceso en la secuencia de DWI en 4 pacientes con trauma craneoencefálico severo y alteración del estado de consciencia, quienes en la fase aguda del trauma fueron estudiados con imágenes convencionales de tomografía y resonancia. MATERIALES Y MÉTODOS: Se describe una serie de 4 casos de pacientes con trauma craneoencefálico severo y alteración del estado de consciencia a quienes se realizó resonancia cerebral simple. Las imágenes fueron sometidas a un posproceso de la secuencia de DWI analizando diferentes regiones por donde transcurren las fibras del sistema reticular activador ascendente (SRAA) (cuerpos restiformes, rafe medio del mesencéfalo, tálamo, regiones subinsulares y lóbulos frontales basales). Igualmente se tomaron valores de difusibilidad en regiones similares, en 5 sujetos sin alteración estructural cerebral tomados como controles. RESULTADOS: Se encontró disminución en la difusibilidad media en las diferentes regiones establecidas en el estudio, que tuvieron diferente localización en cada paciente. Los valores disminuyeron aproximadamente en un 50 % respecto a los del grupo control, observando lesiones en áreas que no fueron identificadas en la interpretación de la imagen cuando fue adquirida durante el trauma. CONCLUSIONES: El posproceso de la secuencia DWI muestra disminución en los valores de difusibilidad media en regiones por donde transcurren las vías del sistema reticular activado ascendente, estos cambios que explican las diferentes alteraciones en el estado de conciencia, no fueron visualizados en las imágenes interpretadas bajo las técnicas convencionales. Se requiere nuevos estudios para establecer las características operativas de la prueba que permitan definir su potencial utilidad dentro de los algoritmos de clasificación inicial de los pacientes con trauma craneoencefálico severo.

SUMMARY INTRODUCTION: Patients with severe traumatic brain injury may have severe neurological sequelae that generate disability of different ranges, according to the Barthel scale. The consciousness impairment is the most serious sequela and is a cause of complete dependence of these patients, due to the loss of self-care. The relationship between abnormal findings in neuroimaging and different states of consciousness has been the subject of research in recent years, with the possibility of new options with the post-processing of magnetic resonance imaging (MRI). This study aims to describe the alterations in the mean diffusivity by post-processing of the diffusion weighted imaging (DWI) sequence in 4 patients with severe traumatic brain injury and impairment of consciousness, who were studied with computed tomography (CT) and MRI in the acute phase of the trauma. MATERIALS AND METHODS: We describe a series of 4 cases of patients with severe traumatic brain injury and impaired consciousness in whom a non-enhanced brain MRI was performed. The DWI sequence images were post-processed, analyzing different regions through which the fibers of the Ascending Reticular Activating System (ARAS) (including restiform bodies, midbrain, thalamus, sub-insular regions and basal frontal lobes) pass. Likewise, diffusivity values were taken in similar regions, in 5 subjects without any structural brain abnormality, who were taken as controls. RESULTS: There was a decrease in mean diffusivity in the different regions established in the study, which had different locations in each patient. Values decreased approximately 50 percent from values in normal patients. After post-processing, some lesions were observed in areas that were not identified in the initial MRI interpretation during the trauma. CONCLUSIONS: The post-processing of the DWI sequence shows a decrease in the mean diffusivity values in regions where the ARAS pathways pass through. These changes explaining the different alterations in consciousness were not visualized in the images interpreted under conventional MRI techniques. New studies are required to establish the operative characteristics of this test, that allow to define its potential utility within the algorithms of initial classification of patients with severe traumatic brain injury.

Reconstruction of the Ascending Reticular Activating System with Diffusion Tensor Tractography in Patients with a Disorder of Consciousness after Traumatic Brain Injury.

This work describes the reconstruction of the ascending reticular activating system (ARAS) with diffusion tensor tractography in three patients with altered consciousness after traumatic brain injury. A diffusion tensor tractography was performed in three patients with impaired consciousness after a severe traumatic brain injury. A 1.5 T scanner was used to obtain the tensor sequences; axial tensors were acquired. Post-processing was performed, and the mean fractional anisotropy (FA) values were recorded. The FA maps were used to do a manual tracing of the following regions of interest (ROIs): the ventromedial midbrain, the anterior thalamus, and the hypothalamus. Case 1 presented destruction of the right dorsal and ventral tegmental tracts as well as destruction of the right middle forebrain bundle, case 2 had destruction of the right dorsal tegmental tract, and case 3 had destruction of the bilateral ventral and dorsal tegmental tracts, as well as destruction of the right middle forebrain bundle. The affected fibers of the ascending reticular activating system with diffuse axonal injury and the FA values abnormalities in the ascending reticular activating system in three patients with a disorder of consciousness (DOC) after traumatic brain injury are described.

Diagnóstico de muerte cerebral: uso de la angiografía por tomografía axial computarizada como herramienta diagnóstica no invasiva al alcance de todos / Diagnosis of Brain Death: Use of Computed Tomography Angiography as a Non-invasive Diagnostic Tool Available to Everyone

Introducción: La muerte cerebral (MC) se define como la pérdida irreversible de la función cerebral y la ausencia de reflejos del tallo cerebral y de movimientos respiratorios. Objetivo: Describir los hallazgos en la angioTAC cerebral en pacientes con signos clínicos de MC, para evaluar su aplicabilidad como método diagnóstico. Métodos: Se realizó un estudio retrospectivo, entre septiembre de 2013 y abril de 2015; se incluyeron pacientes entre 21 y 60 años, a quienes se les practicó angioTAC para verificar MC. El diagnóstico clínico de MC se realizó mediante el examen neurológico y el test de apnea. Adicionalmente se realizó una angioTAC con tomógrafo multicorte de cuatro detectores, con tres adquisiciones, mediante cortes axiales de 2 mm desde el cuerpo vertebral de C6 hasta 5 cm arriba. El diagnóstico escanográfico de MC se hizo basado en criterios de ausencia completa de circulación intracraneal con una escala de 6 puntos. Resultados: Se identificaron 12 pacientes que cumplían con los criterios de inclusión (5 hombres y 7 mujeres), con edad media 46,6 años (21-60). Los diagnósticos de base fueron: neurovascular (n=8), trauma craneoencefálico (n=2), meningioma (n=1) y paro cardiorespiratorio (n=1). Solo un paciente no cumplió con los 6 puntos de los criterios propuestos para la evaluación con angioTAC. Conclusiones: La angioTAC puede suministrar información suficiente para realizar el diagnóstico confirmatorio imaginológico de MC en los pacientes con duda diagnostica clínica; sin embargo, es necesario compararlo en el futuro con la angiografía por catéter.

Introduction: Brain death (BD) is defined as an irreversible loss of brain function, and the absence of reflexes of the brain stem and of respiratory movements. Objective:To describe the brain CT angiography findings in patients with clinical signs of brain death (BD) and to evaluate its applicability as a diagnostic method of BD as well. Methods: A retrospective study was performed between September 2013 and April 2015, which included patients between the ages of 21 and 60, who underwent CT angiography with BD protocol. The clinical diagnosis of BD was made by neurological examination and with an apnea test. Additionally, a multi-slice CT angiography was performed with a 4-detectors tomograph, with three acquisitions, with 2mm axial slices from the vertebral body of C6 to 5 cm above. The BDscan diagnostic criteria was performed based on criteria of complete absence of intra-cranial circulation with a 6 point scale. Results: 12 patients that met the inclusion criteria (5 males and 7 females), with a mean age of 46.6 years (21-60) were identified. The initial diagnosis of the patients were neurovascular (n = 8), head trauma (n = 2), meningioma (n = 1) and cardiopulmonary arrest (n = 1). Only one patient did not meet the 6 points of the proposed criteria for the evaluation with CT angiography. Conclusions: CT angiography could provide enough information to perform confirmatory diagnostic imaging of BD in patients with clinical doubts of diagnosis of BD, however it is necessary in the future to compare it with catheter angiography.

Técnica de la artrorresonancia magnética de hombro / Thecnic of arthro magnetic resonance of shoulder

En este artículo se revisa con detalle la técnica de punción intraarticular, los materiales y el protocolo que debe seguirse en la realización de la artrorresonancia magnética de hombro después de la experiencia en un centro diagnóstico con, aproximadamente, unos doscientos pacientes en cinco años. Luego de analizar la información, se concluye que se han obtenido buenos resultados técnicos y sin complicaciones, y que esta técnica sirve como modelo para otros centros de diagnóstico.