Use of diffusion tensor imaging to assess the vasogenic edema in traumatic pericontusional tissue / Uso de la resonancia de tensor de difusión para estudiar el edema vasogénico pericontusional

Background and objective Cerebral edema is a frequent and serious complication of traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is considered a useful technique to assess white matter integrity after TBI. The objective of this prospective, observational study was to assess the characteristics of the vasogenic edema in the traumatic pericontusional tissue and compare it to the vasogenic edema found in brain tumors. We also included a control group. Methods Using DTI, the Apparent diffusion coefficient (ADC) and Fractional anisotropy (FA) were measured in the area of vasogenic edema in both TBI and tumor patients. The measurements in the control group were done in the gray and white matter. We included 15 TBI patients, 18 tumor patients and 15 controls. Results ADC and FA showed no differences between TBI and tumor patients (p=0.27 for AF; p=0.79 for ADC). Compared to healthy controls, TBI and tumor patients presented higher ADC values and lower FA values. The differences between TBI and controls were statistically significant (p<0.05). Conclusions In this prospective observational study using DTI-MRI in a selected group of mild and moderate TBI patients with vasogenic pericontusional edema we have shown that there were no significant differences of the ADC and FA values compared to brain tumor patients. Furthermore, healthy controls showed significant lower ADC values and higher FA values compared to TBI and tumor patients. Future studies, using DTI-MRI, should address whether any therapy has a favorable impact on the vasogenic edema of TBI patients with brain contusions (AU)

Antecedentes y objetivo El edema cerebral es una complicación grave y frecuente en pacientes con traumatismo craneoencefálico (TCE). La resonancia de tensor de difusión (DTI-RM) es considerada como una técnica de imagen muy útil para valorar la integridad de la sustancia blanca tras un TCE. El objetivo de este estudio prospectivo y observacional es valorar las características del edema vasogénico pericontusional de pacientes traumáticos y comparar dichas zonas con el edema vasogénico de pacientes con tumores cerebrales. También se ha incluido un grupo control. Pacientes y métodos Se ha empleado la DTI-RM para cuantificar el coeficiente de difusión aparente (ADC) y la anisotropía fraccional (AF) en las zonas de edema vasogénico en pacientes con contusiones cerebrales traumáticas y tumores cerebrales. Las mediciones del grupo control se hicieron tanto en la sustancia gris como en la sustancia blanca. Se incluyeron 15 pacientes con TCE, 18 pacientes con tumores cerebrales y 15 controles. Resultados Los valores del ADC y de la AF fueron similares en los pacientes con TCE y tumores cerebrales (p=0.27 para los valores de AF; p=0,79 para los valores de ADC). Respecto a los controles, tanto los pacientes con TCE como con tumores cerebrales presentaron valores más elevados del ADC y valores más bajos de la AF. Las diferencias en estas variables entre los pacientes con TCE y los controles fueron estadísticamente significativas (p<0,05) (AU)

Use of diffusion tensor imaging to assess the vasogenic edema in traumatic pericontusional tissue.

BACKGROUND AND OBJECTIVE: Cerebral edema is a frequent and serious complication of traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is considered a useful technique to assess white matter integrity after TBI. The objective of this prospective, observational study was to assess the characteristics of the vasogenic edema in the traumatic pericontusional tissue and compare it to the vasogenic edema found in brain tumors. We also included a control group. METHODS: Using DTI, the Apparent diffusion coefficient (ADC) and Fractional anisotropy (FA) were measured in the area of vasogenic edema in both TBI and tumor patients. The measurements in the control group were done in the gray and white matter. We included 15 TBI patients, 18 tumor patients and 15 controls. RESULTS: ADC and FA showed no differences between TBI and tumor patients (p=0.27 for AF; p=0.79 for ADC). Compared to healthy controls, TBI and tumor patients presented higher ADC values and lower FA values. The differences between TBI and controls were statistically significant (p<0.05). CONCLUSIONS: In this prospective observational study using DTI-MRI in a selected group of mild and moderate TBI patients with vasogenic pericontusional edema we have shown that there were no significant differences of the ADC and FA values compared to brain tumor patients. Furthermore, healthy controls showed significant lower ADC values and higher FA values compared to TBI and tumor patients. Future studies, using DTI-MRI, should address whether any therapy has a favorable impact on the vasogenic edema of TBI patients with brain contusions.

Effects of dexamethasone in traumatic brain injury patients with pericontusional vasogenic edema: A prospective-observational DTI-MRI study.

Cerebral edema is a frequent and serious complication in traumatic brain injury (TBI) patients. The objective is to study the effect of dexamethasone in patients with brain contusions, and to assess its effect on the vasogenic component of the pericontusional edema.Prospective-observational study to quantify, using magnetic resonance imaging, the volume of the edema before and after 10 days of dexamethasone in patients with brain contusions. Using diffusion tensor imaging, we have examined the effect of dexamethasone on fractional anisotropy (FA) and apparent diffusion coefficient (ADC). To assess changes, the pre- and post-treatment values for each patient were compared using a paired-samples Student t test.We included 30 TBI patients, 15 in each group. The volume of the vasogenic edema in the group of patients treated with dexamethasone decreased from 22 to 19 mL and this decrease was statistically significant (P < .05). Nevertheless, in the non-steroids group the volume of the vasogenic edema increased from 11 to 15 mL. There was a significant decrease in the ADC value (from 1.78-1.59; P < .05); and a significant increase in the FA value (0.09-0.11; P < .05) in the patients treated with dexamethasone.Using diffusion tensor imaging we have shown in a selected group of TBI patients with vasogenic pericontusional edema, a reduction of edema volume, a decrease in the ADC and an increase in the FA after treatment with dexamethasone. However, we have no data if such results are beneficial in terms of improving functional outcome.

Use of diffusion tensor imaging to assess the vasogenic edema in traumatic pericontusional tissue.

BACKGROUND AND OBJECTIVE: Cerebral edema is a frequent and serious complication of traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is considered a useful technique to assess white matter integrity after TBI. The objective of this prospective, observational study was to assess the characteristics of the vasogenic edema in the traumatic pericontusional tissue and compare it to the vasogenic edema found in brain tumors. We also included a control group. METHODS: Using DTI, the Apparent diffusion coefficient (ADC) and Fractional anisotropy (FA) were measured in the area of vasogenic edema in both TBI and tumor patients. The measurements in the control group were done in the gray and white matter. We included 15 TBI patients, 18 tumor patients and 15 controls. RESULTS: ADC and FA showed no differences between TBI and tumor patients (p=0.27 for AF; p=0.79 for ADC). Compared to healthy controls, TBI and tumor patients presented higher ADC values and lower FA values. The differences between TBI and controls were statistically significant (p<0.05). CONCLUSIONS: In this prospective observational study using DTI-MRI in a selected group of mild and moderate TBI patients with vasogenic pericontusional edema we have shown that there were no significant differences of the ADC and FA values compared to brain tumor patients. Furthermore, healthy controls showed significant lower ADC values and higher FA values compared to TBI and tumor patients. Future studies, using DTI-MRI, should address whether any therapy has a favorable impact on the vasogenic edema of TBI patients with brain contusions.