Acute and chronic MRI changes in the spine and spinal cord after surgical stem cell grafting in patients with definite amyotrophic lateral sclerosis: post-infusion injuries are unrelated with clinical impairment.

OBJECTIVE: To report MRI spinal changes after surgical infusion of bone marrow stem cells (BMSc) in ALS patients and assess their correlation with clinical events and functional performance. METHODS: BMSc were surgically injected in the thoracic spinal cord of 11 ALS patients (6/5 male/female; median age 46years). We performed first-week and third, sixth, ninth and twelfth post-surgical months spinal MRIs. The spinal changes in the postsurgical week and follow-up MRIs, as well as clinical events, functional scales and respiratory and electromyography data, were longitudinally monitored. Correlations between the imaging and clinical data were evaluated with the Spearman's test. RESULTS: Transient extradural fluid collections (100%), transient spinal cord T2 hyperintensity (81.8%), and chronic spinal cord deformities (63.6%) were the dominating MRI changes. Spinal cord hemorrhages (27.3%) and cystic myelomalacia (1/11 patients) were important although unusual findings. During the follow-up, minor adverse events of mild to moderate intensity eventually improved. Initial and follow-up imaging scores showed a strongly positive correlation (r 0.879, P<0.001). The initial and delayed clinical scores did not correlate. There was no significant correlation between any of the imaging scores and clinical data. CONCLUSIONS: Infusion of BMSc produces a variety of spinal changes apparently unrelated with clinical events and disease worsening.

Posterior paralimbic and frontal metabolite impairments in asymptomatic hypertension with different treatment outcomes.

Hypertension is associated with cognitive decline in elderly persons. We studied asymptomatic hypertensive subjects using brain magnetic resonance (MR) spectroscopy to evaluate metabolite impairments before the appearance of symptoms in patients with different treatment outcomes. In all, 14 healthy controls and 37 asymptomatic hypertensive patients (17 controlled and 20 resistant) underwent brain structural MR and MR spectroscopy of the posterior paralimbic (PPL) area and left frontal white matter. Ischemic burden (IB), global cortical atrophy and microbleeds were analyzed with visual scales. Metabolite ratios involving N-acetyl-aspartate (NAA), creatine (Cr), choline (Cho) and myoinositol (mI) were computed. Ultrasound measurements, including intima-media thickness, plaques and hemodynamic ratios, were obtained. Intergroup differences in IB, atrophy and metabolite ratios, and the atrophy and IB relationship were assessed with parametric and nonparametric statistical tests. In addition, the impacts of demographic, analytic and clinical factors, ischemia and atrophy, and ultrasound measurements on metabolite ratios were assessed. The significance level was set at P

ADC measurements at low and high b values: insight into normal brain structure with clinical DWI.

PURPOSE: To demonstrate drop in brain ADC measurements from low to high b values; to evaluate the structural information provided based on those changes; and to discuss the anatomical reasons for ADC differences. METHODS: Four cerebral ROI (precuneus-PRC, hippocampus-HIP, and the genu-GCC and splenium-SCC of the corpus callosum-CC) were drawn for ADC measurements with low (1000) and high (3000) b-value DWI in 50 normal subjects. ANOVA and Bonferroni correction tested ADC differences between areas, between both hemispheres, between GCC and SCC, and between b-value related ADC drop within areas. Pearson test evaluated dependence of interhemispheric and intercallosum ADC measurements obtained with the same b-value, dependence between areas of intrazonal drop, and the interhemispheric and intercallosum dependence of intrazonal drop. RESULTS: ADCs differed between areas (P<.0001). Interhemispheric ADC only differed in PRC with low b-value (P<.027). No HIP asymmetries occurred regardless the b-value. ADC drop within PRC and HIP was similar but differed (P<.0001) from ADC drop within both CC ROI. ADC drop was also different between GCC and SCC (P<.0001). In PRC and HIP, ADC showed a significant interhemispheric and intrazonal dependence (P<.0001). There was no GCC to SCC ADC dependence. Intrazonal dependence in the CC was only significant in the SCC (P<.001). Interhemispheric dependence of intrazonal drop was significant (PRC P=.007; HIP P<.0001) but failed to reach significance in the CC. CONCLUSION: Low and high b-value measurements show different diffusion behaviours within different tissues, especially in a highly anisotropic structure as the corpus callosum. This fact can provide valuable information about brain structure and different diffusion compartments in clinical DWI.

Basal ganglia and thalamic tumours: an imaging approximation.

INTRODUCTION: Among brain tumours, those arising from the deep brain are rare. In many cases they are low-grade astrocytomas. But primitive neuroectodermal tumours, ganglion cell tumours, oligodendrogliomas, lymphomas, and germinal neoplasms can also grow up from the basal ganglia and thalamic region. In other occasions peripheral neoplasms developing in neighbouring structures like the cerebral lobes, the ventricular walls, choroidal plexus, pineal gland and the hypothalamic-chiasmatic-suprasellar region can spread to the deep brain. IMAGING: Imaging cannot reliably indicate that a histological picture for a tumour of this kind should be suspected. Although the macro- and microscopical characteristics of brain tumours are often the basis of the imaging findings, these data usually overlap and are only useful as an approximation tool. CONCLUSIONS: Nonetheless, whilst radiologists and clinicians must always be cautious when evaluating the macroscopic peculiarities of a brain tumour, the value of imaging cannot be overestimated when any sort of pathology is encountered. Moreover, besides the classic CT and MRI findings, new MRI-related techniques, such as magnetic resonance spectroscopy (MRS), are able to extract a different kind of information from cerebral neoplasms, and they could be important widespread diagnostic alternatives in the very near future.

El interpolador de alto orden: un medio para incrementar la resolución de las imágenes pulmonares obtenidas mediante tomografía computarizada espiral / The high-grade interpolator: a means for enhancing the resolution of helical computed tomography images of the lung

Objetivos: Nuestro trabajo pretende demostrar que la aplicación de un interpolador de alto orden en la reconstrucción de las imágenes torácicas aumenta la resolución, independientemente del filtro de alta resolución. Material y métodos: Ocho observadores separados en dos grupos (de expertos y de inexpertos) valoraron (en dos lecturas separadas en el tiempo) la misma sección torácica reconstruida cuatro veces (st-st, st-xs, b-st, b-xs), combinando los filtros (estándar-st y alta resoluciónb) y los interpoladores (estándar-st y alto orden-xs). Clasificaron las imágenes de más a menos según la resolución percibida. Los resultados se utilizaron para comparar tanto el grado de resolución introducido por el interpolador y el filtro, como la existencia o no de variabilidad entre observadores y entre sus propias observaciones, influida o no por la experiencia. Resultados: Seis de los ocho observadores clasificaron la imagen b-xs como la de mayor resolución en la mayoría de las ocasiones. En segundo lugar se clasificó la imagen b-st. En tercero la imagen st-xs. En último lugar la imagen st-st. Los otros dos observadores (uno entre los expertos y otro en los inexpertos) difirieron sólo en el orden de las imágenes st-xs y b-st, que fueron clasificadas en segundo y tercer lugar respectivamente. El grupo de expertos no mostró variabilidad intraobservador aunque sí dos de los inexpertos. Conclusiones: El interpolador de alto orden aumenta la resolución de las imágenes torácicas, independientemente de quien las evalúe, sin un aumento importante del ruido. Este hecho hace aconsejable su uso en las exploraciones torácicas con TC espiral (TCE). (AU)

Los quistes aracnoideos en la enfermedad renal poliquística autosómica dominante / Arachnoid cysts in autosomal dominant polycystic kidney disease

La enfermedad renal poliquística autosómica dominante (ERPAD) es una enfermedad sistémica con una relación conocida con los aneurismas intracraneales. Algunos estudios demuestran también una relación de la ERPAD con los quistes aracnoideos.Describimos los hallazgos de tres hermanas, cuyo padre sufrió una ERPAD. Dos de las hermanas tenían quistes aracnoideos, debutando una de ellas con un hematoma subdural. Nuestras pacientes no presentaban datos morfológicos ni analíticos de enfermedad renal avanzada aunque sí de afectación incipiente. Todos estos datos sugieren que los quistes aracnoideos en la ERPAD no son necesariamente un hallazgo de fases tardías de la enfermedad y pueden ser otro motivo de hemorragia intracraneal (AU)