Acute brain MRI-DWI patterns and stroke recurrence after mild-moderate stroke.

Brain ischemic lesions identified by diffusion-weighted imaging (DWI) have been shown to predict high risk of early future ischemic events in patients with transient ischemic attacks and minor stroke. The aim of this study is to analyze different brain MRI-DWI patterns in patients with mild-moderate stroke to define acute patterns related with a higher risk of stroke recurrence in long-term follow-up (from 6 to 36 months). Retrospective review of case series from a prospective stroke record including 253 patients with mild-moderate stroke (NIHSS from 1 to 7) and acute MRI-DWI lesions. MRI-DWI lesions were analyzed to determine clinically relevant lesions, based on the number, location, age and affected arterial territories. We defined three patterns: (1) multiple versus single lesions; (2) single deep versus single cortical lesions; and (3) single lesions versus multiple lesions affecting different arterial territories and/or of different age. The impact of these patterns on recurrence was analyzed by Cox regression analysis. 38 patients (15.0%) suffered a recurrence. Univariate analysis showed the risk of recurrence for each pattern. Pattern 1: patients with multiple lesions had greater risk of recurrence than those with single lesions (28.2 vs. 9.9%; OR: 3.75 (95% CI: 1.76-7.27), p < 0.0001). Pattern 2: patients with single cortical lesions had higher risk than those with deep lesions (14.3 vs. 6.7% OR: 2.33 (95% CI: 0.86-6.33), p < 0.089). Pattern 3: patients with multiple DWI in different territories or different age had the highest recurrence rate (30.6%), OR: 4.01 (95% CI: 1.70-9.47), p < 0.001, compared to patients with single lesions. Cox regression analysis adjusted by possible confounders, showed that for pattern 1 the OR for recurrence was 2.49 (95% CI: 1.27-4.89), p = 0.008; for pattern 2, OR:1.99 (95% CI: 0.74-5.37), p = 0.17; for pattern 3, OR: 2.85 (95% CI: 1.31-6.15), p = 0.008. Brain MRI-DWI patterns assessed in the acute phase of mild-moderate stroke are useful to identify those patients at high risk of recurrence.

Influence of the fusiform gyrus on amygdala response to emotional faces in the non-clinical range of social anxiety.

BACKGROUND: Social anxiety often involves a combination of hypervigilance and avoidance to potentially warning signals including the facial expression of emotions. Functional imaging has demonstrated an increase in amygdala response to emotional faces in subjects with social anxiety. Nevertheless, it is unclear to what extent visual areas processing faces influence amygdala reactivity in different socially anxious individuals. We assessed the influence of the fusiform gyrus activation on amygdala response to emotional faces in the non-clinical range of social anxiety. METHOD: Twenty-two normal subjects showing a wide range in social anxiety scores were examined using functional magnetic resonance imaging (fMRI) during the processing of happy and fearful faces. A dimensional analysis approach was used involving voxel-wise mapping of the correlation between subjects' social anxiety scores and amygdala activation, before and after controlling for fusiform gyrus activation. RESULTS: We observed that only after controlling for subjects' level of activation of the fusiform gyrus was there an association between social anxiety ratings and amygdala response to both happy and fearful faces. The fusiform gyrus influence was more robust during the fear condition. Of note, fusiform gyrus response to fearful faces showed a negative correlation with additional behavioral assessments related to avoidance, including social anxiety scores, harm avoidance and sensitivity to punishment. CONCLUSIONS: Relevant interactions among the emotional face-processing stages exist in the non-clinical range of social anxiety that may ultimately attenuate amygdala responses. Future research will help to establish the role of this effect in a clinical context.

Quantification and characterization of carotid calcium with multi-detector CT-angiography.

OBJECTIVE: The aim of this study was to assess the accuracy of CT-angiography for identification and measurement of calcification of carotid atherosclerotic plaques and to characterise the content and distribution pattern of mineral calcium (hydroxyapatite, Ca) in carotid bifurcations and investigate its relationship with neurological symptoms. METHODS: Twenty-six patients with ICA stenosis > 60% (13 symptomatic, 13 asymptomatic) were selected for study. Ca was estimated from the weight of the ashed remnants of carotid endarterectomy (CEA) specimens in 11 patients. Calcium content (calcification volume (mm3),CV), and average calcium density (Hounsfield units (HU),CD), were determined by CT-angiography. The distribution pattern of calcium within the lesion (base (posterior), shoulder or luminal surface) was assessed in all cases. RESULTS: CT-derived estimation of CV and Ca mass (modified Agatston Score, (mAS) = CV x CD) showed a good correlation with its direct measurement in CEA specimens (r = 0.911 and 0.993 respectively, p < 0,005). Asymptomatic patients with ICA stenosis > 60% showed statistically significant higher content of Ca than those who were symptomatic (mAS: 122.6 +/- 138.0 HU mm3 vs 42.8 +/- 59.1 HU mm3, p = 0.04). Calcification on the surface of the plaque was observed more commonly in asymptomatic patients (9/12 vs 3/15, p = 0.006). Non-calcified or plaques with posterior calcification were 12 times more likely to be symptomatic (OR: 12, 95%CI 1.5-91.1, p = 0.021). CONCLUSIONS: CT-angiography permits the reliable quantification of calcification of carotid plaques. A lower content of calcium in carotid plaques, as well as its distribution in the base of the lesion, was associated with a greater prevalence of neurological symptoms. These parameters may be useful to identify those patients at higher risk of stroke.

Infartos medulares óseos / Bone marrow infarcts

Objetivo: Conocer las características clínicas, evolución y etiología de los infartos medulares óseos (IMO). Métodos: Tras la detección de un caso centinela se revisa la base de datos de los últimos 5 años de nuestro centro, y se detectó a 5 pacientes con las características prefijadas, de un total de 8.200 exploraciones osteoarticulares realizadas. Resultados: Caso 1: varón de 41 años con antecedentes de hipercolesterolemia, trasplante renal e inmunosupresión posterior, clínica de coxalgia bilateral y resonancia magnética (RM) que presenta imágenes compatibles en cabezas y cuellos femorales; caso 2: varón de 44 años con antecedentes de síndrome de Raynaud y asma bronquial con corticoterapia en las descompensaciones, clínica de gonalgia bilateral y RM que muestra lesiones compatibles en ambos fémures y tibias; caso 3: varón de 43 años con antecedentes de infección por el VIH y enfermedad pulmonar obstructiva crónica (EPOC) con corticoterapia, clínica de dolor mecánico en tobillo izquierdo y RM que presenta múltiples lesiones compatibles en la tibia, astrágalo, calcáneo y escafoides; caso 4: mujer de 59 años sin antecedentes relacionados ni clínica, con RM que evidencia lesión compatible en cuello femoral derecho; caso 5: varón de 42 años con antecedentes de enolismo y osteonecrosis (ON) de cabeza femoral izquierda, clínica de gonalgia mecánica y RM que presenta lesiones compatibles en tibia y cóndilo femoral interno. Discusión: Los IMO son una entidad infrecuente y poco descrita, cuya imagen en RM es la de una lesión ósea intramedular de contornos serpiginosos, hipo o isointensa en T1 e hiperintensa en T2. Aparecen como lesiones segmentarias, sin afección cortical y normalmente múltiples. Difieren de la típica ON pero pueden asociarse a ella, intuyendo un posible origen Infartos medulares óseos común. A las causas reconocidas en nuestro centro, la revisión bibliográfica permite añadir otras enfermedades causales. Se cita la posible malignización de la lesión a sarcomas óseos. (AU)

Reflex sympathetic dystrophy syndrome of the lower limbs in a renal transplant patient treated with tacrolimus.

BACKGROUND: Recently, a previously unrecognized posttransplant syndrome known as reflex sympathetic dystrophy syndrome of the lower limbs has emerged in patients receiving cyclosporine as immunosuppression. We describe herein this complication observed in a patient treated with tacrolimus after kidney transplantation. METHODS: A 49-year-old man received a kidney transplant from a cadaver donor and was treated with tacrolimus. Three months later, the patient complained of severe pain in the lower limbs that affected both knees and ankles. Bone scintigraphy and magnetic resonance were consistent with reflex sympathetic dystrophy syndrome. RESULTS: Laboratory tests that included creatinine, glomerular filtration rate, calcium, phosphate, urate, alkaline phosphatase, and parathormone were normal or near normal. Tacrolimus levels were around 13 microg/ml. Clinical improvement appeared slowly and spontaneously during the following 3 months, without appreciable changes in the tacrolimus level. CONCLUSIONS: In kidney transplant patients, tacrolimus could be a risk factor for the development of a reflex sympathetic dystrophy syndrome.