Acute pulmonary embolism detection with ventilation/perfusion SPECT combined with full dose CT: what is the best option? / SPECT/TC de ventilación-perfusión pulmonar en el diagnóstico del tromboembolismo pulmonar agudo

Aim. To compare diagnostic accuracy of Ventilation/Perfusion (V/P) single-photon emission computed tomography (SPECT) combined with simultaneous full-dose CT with a hybrid SPECT/CT scanner versus planar ventilation/perfusion (V/P) SPECT and CT angiography (CTA) in patients suspected with acute pulmonary embolism (PE). Methods. Between 2009 and 2011, consecutive patients suspected of acute PE were referred for V/P SPECT/CT (reviewed board approved study). A contrast agent was administered to patients who had no contraindications. Non-contrast V/P SPECT/CT was performed on the remaining patients. All patients were followed-up for at least 3 months. Results. A total of 314 patients were available during the study period, with the diagnosis of PE confirmed in 70 (22.29%) of them. The overall population sensitivity and specificity was 90.91% and 92.44%, respectively for V/P SPECT, 80% and 99.15%, respectively, for CTA, and 95.52% and 97.08% for V/P SPECT/CT. SPECT/CT performed better than V/P SPECT (AUC differences=0.0419, P=0.0043, 95% CI; 0.0131-0.0706) and CTA (AUC differences=0.0681, P=0.0208, 95% CI; 0.0103-0.1259)). Comparing imaging modalities when contrast agent could be administered, sensitivity and specificity increased and V/P SPECT/CT was significantly better than CTA (AUC differences=0.0681, P=0.0208, 95% CI; 0.0103-0.1259) and V/P SPECT (AUC differences=0.0659, P=0.0052, 95% CI; 0.0197-0.1121). In case of non-contrast enhancement, there was non-significant increase of specificity. Secondary findings on CT impacted patient management in 14.65% of cases. Conclusion. Our study shows that combined V/P SPECT/CT scanning has a higher diagnostic accuracy for detecting acute PE than V/P SPECT and CTA alone. When feasible, V/P SPECT/CT with contrast enhancement is the best option (AU)

Objetivo del estudio. Valorar la exactitud diagnóstica de la SPECT/TC de ventilación-perfusión (V/P) pulmonar de alta dosis mediante un equipo híbrido SPECT/TC frente a la SPECT de V/P pulmonar y a la angiografía por TC (CTA) en pacientes con sospecha de tromboembolismo pulmonar (TEP) agudo. Metodología. Entre 2009 y 2011, se estudiaron de forma consecutiva con SPECT/TC de V/P pulmonar los pacientes con sospecha de TEP agudo que acudieron a nuestro centro (estudio aprobado por el comité de ética hospitalaria). A los pacientes que no presentaban contraindicaciones se les administró contraste yodado (CI) por vía intravenosa. En el resto se realizó un estudio SPECT/TC de V/P pulmonar sin CI. Los pacientes fueron seguidos durante un período de 3 meses. Resultados. Se estudiaron un total de 314 pacientes. En 70 (22,29%) se confirmó el diagnóstico de TEP. La sensibilidad y especificidad para la población global fue: 90,91 y 92,44% respectivamente para la SPECT de V/P; 80 y 99.15% para la CTA; y 95.52 y 97.08% para la SPECT/TC de V/P pulmonar. La SPECT/TC presentaba una exactitud diagnóstica superior a la SPECT de V/P (diferencias AUC=0,0419; p=0,0043; IC95%: 0,0131-0,0706) y la CTA (diferencias AUC=0,0681, p=0,0208; IC95%: 0,0131-0,1259). Comparando las diferentes modalidades cuando se administró CI, observamos un aumento de la sensibilidad y la especificidad de la SPECT/TC de V/P superior a la CTA (diferencias AUC=0,0681; p=0,0208; IC95%: 0,0131-0,1259) y a la SPECT de V/P (diferencias AUC=0,0659; p=0,0052; IC95%: 0,0197-0,1121). En el caso de no administrar CI se observó un aumento no estadísticamente significativo de la especificidad. Los hallazgos secundarios de la TC provocaron un cambio en el manejo del paciente en un 14,65% de los casos. Conclusión. Nuestro estudio demuestra que el estudio combinado SPECT/TC de V/P pulmonar tiene una mayor exactitud diagnóstica para detectar el TEP agudo que la SPECT de V/P pulmonar o la CTA por sí solos. Cuando es factible, la SPECT/TC de V/P pulmonar con CI es la mejor opción diagnóstica (AU)

Acute pulmonary embolism detection with ventilation/perfusion SPECT combined with full dose CT: What is the best option?

AIM: To compare diagnostic accuracy of Ventilation/Perfusion (V/P) single-photon emission computed tomography (SPECT) combined with simultaneous full-dose CT with a hybrid SPECT/CT scanner versus planar ventilation/perfusion (V/P) SPECT and CT angiography (CTA) in patients suspected with acute pulmonary embolism (PE). METHODS: Between 2009 and 2011, consecutive patients suspected of acute PE were referred for V/P SPECT/CT (reviewed board approved study). A contrast agent was administered to patients who had no contraindications. Non-contrast V/P SPECT/CT was performed on the remaining patients. All patients were followed-up for at least 3 months. RESULTS: A total of 314 patients were available during the study period, with the diagnosis of PE confirmed in 70 (22.29%) of them. The overall population sensitivity and specificity was 90.91% and 92.44%, respectively for V/P SPECT, 80% and 99.15%, respectively, for CTA, and 95.52% and 97.08% for V/P SPECT/CT. SPECT/CT performed better than V/P SPECT (AUC differences=0.0419, P=0.0043, 95% CI; 0.0131-0.0706) and CTA (AUC differences=0.0681, P=0.0208, 95% CI; 0.0103-0.1259)). Comparing imaging modalities when contrast agent could be administered, sensitivity and specificity increased and V/P SPECT/CT was significantly better than CTA (AUC differences=0.0681, P=0.0208, 95% CI; 0.0103-0.1259) and V/P SPECT (AUC differences=0.0659, P=0.0052, 95% CI; 0.0197-0.1121). In case of non-contrast enhancement, there was non-significant increase of specificity. Secondary findings on CT impacted patient management in 14.65% of cases. CONCLUSION: Our study shows that combined V/P SPECT/CT scanning has a higher diagnostic accuracy for detecting acute PE than V/P SPECT and CTA alone. When feasible, V/P SPECT/CT with contrast enhancement is the best option.

Chronic traumatic pseudoaneurysm of right subclavian artery.

A right subclavian artery pseudoaneurysm caused by blunt trauma is described. CT and digital subtraction angiography helped us to establish a correct diagnosis. Radiologic features of subclavian artery aneurysms and relevant literature are briefly discussed.

Radiographic appearance of nosocomial legionnaires' disease after erythromycin treatment.

Radiographic features of 71 patients (48 men, 23 women) with nosocomial Legionella pneumophila pneumonia were assessed and compared with those of other nosocomial series of L pneumophila pneumonia. Sixteen patients were assessed retrospectively and 55 prospectively. Chest radiographs were assessed at the onset of the illness, 10 days later, and at 3 months. Erythromycin was given to 67 patients at the time of the diagnosis and to the remaining four at a later stage. Forty eight patients were over the age of 60. On the initial chest radiograph 53 of the 71 patients had unilateral shadowing (23 of them in the right lung); 35 had unilobar shadowing and the remaining 36 had more than one affected lobe. Pleural effusion was present in 24 cases and cavitation in 2. One patient had evidence of a pericardial effusion. At 10 days 21 patients had evidence of radiographic progression (14 ipsilateral), but 28 had improved. At 3 months 36 patients had an abnormal radiograph, 30 showing residual scarring, 15 loss of volume, six pleural shadows and two cavitation. Our series shows a lesser incidence of unilateral shadowing and pleural effusion than other nosocomial series and a lesser tendency to progression, but more patients had radiographic abnormalities at long term follow up.

Case report: uncommon radiological and pathological features of giant colonic diverticula.

A case of multiple giant sigmoid diverticula is described in which a barium enema revealed two giant diverticula communicating with the sigmoid lumen. Both diverticula were located on the mesenteric border of the sigmoid colon, and histologic examination showed mucosal and serosal layers with no evidence of smooth muscle. The pathogenesis, pathology, radiological manifestations and differential diagnosis of this rare condition are discussed.