Which imaging modalities are most effective for confirming the diagnosis of SVCO in primary care settings?

For confirming the diagnosis of superior vena cava (SVC) obstruction, contrast-enhanced computed tomography (CT) is considered the most effective imaging modality [3, (Sonavane et al., 2015), (Shah et al., 2023)]. This imaging technique provides comprehensive details regarding the extent of the obstruction, the presence of collateral circulation, and often helps identify the underlying cause, such as a tumour [3, (Sonavane et al., 2015), (Shah et al., 2023)]. For instance, in suspected lung cancer, which is a common cause of SVC obstruction, contrast-enhanced CT of the chest, abdomen, and pelvis is recommended for staging and would reveal SVC involvement ³. Magnetic resonance imaging (MRI) can be used as an alternative, particularly when contrast is contraindicated or for further evaluation of tumour invasion and collateral pathways (Sonavane et al., 2015), (Shah et al., 2023). While a chest X-ray may show signs like mediastinal widening, it is not definitive for confirming SVC obstruction (Baker and Barnes, 1992), (Shah et al., 2023). In primary care, suspicion of SVC obstruction based on clinical signs and symptoms would typically lead to an urgent referral for these advanced diagnostic imaging studies in secondary care ³.