Correct!

Answer: 1. Viral pneumonia

The thoracic CT in Figure 2 shows multiple thin-walled cysts (arrowheads), irregular nodules (double arrowheads), and cysts with mural nodules (arrows). One of the larger opacities with a “nodule-in-cyst” morphology is located in the right middle lobe adjacent to the right cardiac border (arrowhead in Panel E). Soft tissue windows (second movie on previous page) show that the pulmonary nodular opacities are non-calcified.

While the other diagnoses listed are quite rare, viral pneumonias typically cause airway thickening, centrilobular nodules, areas of consolidation, and multifocal ground-glass opacity, not nodules and cystic pulmonary lesions with mural nodules. However, the other lesions listed may present with such an appearance.)

The patient then underwent 2-[18F]-Fluoro-2-Deoxy-D-Glucose positron emission computed tomography-CT (FDG-PET CT) to evaluate the pulmonary nodules (Figure 3).

Figure 3. 2-[18F]-Fluoro-2-Deoxy-D-Glucose positron emission computed tomography-CT fused images.

Which of the following statements is correct?   

1. The FDG-PET scan findings allow the confident exclusion of thoracic malignancy
2. The FDG-PET scan findings strongly suggest intrathoracic spread of infection
3. The FDG-PET findings are non-specific, and multiple differential diagnostic possibilities must be considered
4. The FDG-PET scan is non-diagnostic due to technical considerations resulting from lack of patient fasting prior to injection of the radiotracer
5. The FDG-PET scan results are diagnostic of two separate diagnoses likely account for the thoracic findings

Home/Imaging