Nonembolic high-probability perfusion lung scan for pulmonary thromboembolism.
Pulmonary thromboembolism (PTE) is a disease whose diagnosis in the emergency department constitutes a challenge to the clinician. Perfusion lung scans have been important in helping in this context, mainly because of the fact that a normal perfusion lung scan rules out the presence of a clinically significant PTE. Nevertheless, false-positive results are sometimes observed, causing a diagnostic dilemma. An example is a case of bronchogenic carcinoma involving a pulmonary artery or its branches. In such patients, some characteristics of the scintigraphic imaging could guide the diagnosis toward a nonembolic origin of the perfusion defect. A case of small-cell carcinoma of the lung involving the left pulmonary artery whose clinical presentation suggested considering the possibility of PTE is reported. The so-called "stripe sign" is reviewed, and certain clues for the differential diagnosis of a massive and one-sided perfusion defect are discussed.
Martino
J
J
Department of Emergency Medicine, Hospital Central de Asturias, Oviedo, Spain.
Allende
J
J
Herrero
A
A
Colunga
E
E
Martínez
L
L
Escudero
C
C
Del Busto
F
F
D000368:Aged; D001706:Biopsy; D001999:Bronchoscopy; D002283:Carcinoma, Bronchogenic / Q000150:complications* / Q000175:diagnosis / Q000556:secondary; D018288:Carcinoma, Small Cell / Q000150:complications* / Q000175:diagnosis / Q000556:secondary; D003937:Diagnosis, Differential; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D008479:Mediastinal Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000556:secondary; D011651:Pulmonary Artery; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000209:etiology; D011877:Radionuclide Imaging; D014057:Tomography, X-Ray Computed; D014692:Ventilation-Perfusion Ratio