[Noninvasive diagnosis of cerebral venous thrombosis]. / Diagnóstico de trombosis venosas cerebrales mediante técnicas no invasivas.

OBJECTIVES: Cerebral venous thrombosis (CVT) is an uncommon condition. Its variable, unspecific clinical presentation causes delays in diagnosis. We analyze the validity of different neuroimaging techniques, including CT, MRI, MR angiography, and conventional angiography in the diagnosis of CVT. MATERIAL AND METHODS: We review the imaging findings of 12 patients with the final diagnosis of CVT. All 12 patients underwent CT as the initial imaging test; all 12 underwent MRI; 11 underwent MR angiography; and 4 underwent conventional angiography. Visualization of the thrombus or filling defects in the affected vessel were considered direct signs of CVT, whereas findings compatible with venous infarction were considered indirect signs. RESULTS: Of the 12 CT examinations, 4 showed direct signs, 2 indirect signs, and 6 only normal findings. Indirect signs of CVT were seen on follow-up CT in three of the patients with normal initial CT examination. CT failed to show the real extent of the process except in one case in which a cortical vein was affected. MRI detected thrombi in the affected territory in 6 cases; the empty delta sign was seen in 2 and signs of venous infarction in 8. MRI failed to diagnose CVT in one case. MR angiography showed direct signs of CVT in all cases, even without intravenous contrast, and the results were similar to those seen at conventional angiography. More than two locations were affected in 11 patients. CONCLUSIONS: At CT, indirect signs of CVT are seen, although sometimes not immediately. Direct signs can be so subtle that they can only be interpreted with experience. Furthermore, CT does not show the real extent of the process. Nevertheless, given its availability, contrast-enhanced CT should be the primary imaging test, both to rule out other possibilities and to indicate other neuroimaging studies, in this case MRI and MR angiography. The results obtained when these two techniques are performed simultaneously, even without contrast administration, are sufficient for diagnosis and are comparable to those at conventional angiography, but without the risks entailed and without exposing the patient to ionizing radiation.

Diagnóstico de trombosis venosas cerebrales mediante técnicas no invasivas / Noninvasive diagnosis of cerebral venous thrombosis

Objetivos. La trombosis venosa cerebral (TVC) es una patología poco frecuente. Su presentación clínica es inespecífica y variable, lo que ocasiona retrasos en el diagnóstico. Analizamos la validez de las diferentes pruebas de neuroimagen, tomografía computarizada (TC), resonancia magnética (RM), angio-resonancia magnética (RMV) y angiografía, en el diagnóstico de TVC. Material y métodos. Estudio retrospectivo sobre 12 pacientes con diagnóstico final de TVC. Se realizó TC, que fue la prueba inicial, y RM a todos los pacientes, a 11 RMV y en 4 ocasiones se hizo angiografía. Se valoraron como signos directos la visualización del trombo o defectos de repleción en el vaso afecto y como signo indirecto la identificación de hallazgos compatibles con infarto venoso. Resultados. De las 12 TC, 4 mostraron signos directos, 2 indirectos y 6 fueron normales; de éstas, en 3 pacientes se objetivaron signos indirectos en TC evolutivos. No mostró la extensión real del proceso salvo en un caso de afectación localizada de una vena cortical. En la RM se objetivó ocupación de los vasos del territorio venosos afecto en 6 casos, en 2 se apreció el signo del delta vacío y en 8 signos de infarto venoso. En una ocasión no fue diagnóstica. En todas las RMV se visualizaron signos directos de TVC, incluso sin contraste intravenoso. Los resultados fueron similares a los de las angiografías. Once pacientes presentaban afectación de más de 2 localizaciones. Conclusiones. La TC pone de manifiesto signos indirectos, a veces de modo tardío, y signos directos tan sutiles que requieren experiencia para ser interpretados. Además no valora la extensión real del proceso. De todos modos debe utilizarse como técnica de primer nivel, con contraste intravenoso, dada su disponibilidad en la mayoría de los centros, para excluir otras causas y servir para la indicación de otras pruebas de neuroimagen, en este caso RM y RMV. Los resultados obtenidos con la realización simultánea de ambas son equiparables a los de la angiografía, evita los riesgos de esta técnica, no expone al paciente a radiaciones ionizantes y es diagnóstica incluso sin la administración de contraste

Objectives. Cerebral venous thrombosis (CVT) is an uncommon condition. Its variable, unspecific clinical presentation causes delays in diagnosis. We analyze the validity of different neuroimaging techniques, including CT, MRI, MR angiography, and conventional angiography in the diagnosis of CVT. Material and methods. We review the imaging findings of 12 patients with the final diagnosis of CVT. All 12 patients underwent CT as the initial imaging test; all 12 underwent MRI; 11 underwent MR angiography; and 4 underwent conventional angiography. Visualization of the thrombus or filling defects in the affected vessel were considered direct signs of CVT, whereas findings compatible with venous infarction were considered indirect signs. Results. Of the 12 CT examinations, 4 showed direct signs, 2 indirect signs, and 6 only normal findings. Indirect signs of CVT were seen on follow-up CT in three of the patients with normal initial CT examination. CT failed to show the real extent of the process except in one case in which a cortical vein was affected. MRI detected thrombi in the affected territory in 6 cases; the empty delta sign was seen in 2 and signs of venous infarction in 8. MRI failed to diagnose CVT in one case. MR angiography showed direct signs of CVT in all cases, even without intravenous contrast, and the results were similar to those seen at conventional angiography. More than two locations were affected in 11 patients. Conclusions. At CT, indirect signs of CVT are seen, although sometimes not immediately. Direct signs can be so subtle that they can only be interpreted with experience. Furthermore, CT does not show the real extent of the process. Nevertheless, given its availability, contrast-enhanced CT should be the primary imaging test, both to rule out other possibilities and to indicate other neuroimaging studies, in this case MRI and MR angiography. The results obtained when these two techniques are performed simultaneously, even without contrast administration, are sufficient for diagnosis and are comparable to those at conventional angiography, but without the risks entailed and without exposing the patient to ionizing radiation