Contrast-enhanced transcranial color-coded sonography in acute hemispheric brain infarction

Conventional ultrasound methods often fail to provide clear diagnostic results in acute stroke patients due to poor insonation conditions. Prior research has shown that transcranial color-coded sonography (TCCS) is limited in these cases. That uncertainty drove the need for alternative diagnostic approaches. It was already known that middle cerebral artery (MCA) occlusion is a common cause of hemispheric infarction. However, no prior work had resolved how to improve ultrasound imaging in these challenging patients. This gap motivated the exploration of contrast-enhanced TCCS (CE-TCCS) as a potential solution. The method aims to enhance diagnostic accuracy by using echo contrast agents. This study sought to determine whether CE-TCCS could overcome the limitations of standard TCCS in acute stroke evaluation.

The researchers aimed to assess the diagnostic value of CE-TCCS in patients with acute hemispheric infarction and inadequate unenhanced TCCS results. They focused on the MCA territory, where stroke is most frequently observed. The motivation was to evaluate whether CE-TCCS could provide reliable information about MCA occlusion or flow velocity changes. The study also aimed to correlate CE-TCCS findings with clinical, angiographic, and CT results. A secondary goal was to determine if CE-TCCS could predict infarction size and clinical outcomes. The researchers wanted to establish whether this method could serve as a diagnostic alternative when conventional TCCS is insufficient. They also sought to evaluate the method’s potential to guide treatment decisions, such as thrombolytic therapy. The ultimate goal was to determine the feasibility and accuracy of CE-TCCS in this patient population.

The study included 90 acute stroke patients with inadequate unenhanced TCCS insonation. Each patient underwent CE-TCCS, clinical assessments, and CT scans at multiple time points. A subset of 39 patients also had CT angiography (CTA) for comparison. The researchers used a galactose-based echo-enhancing agent to improve ultrasound visibility. They evaluated whether CE-TCCS could detect MCA occlusion or flow velocity changes. The method involved measuring flow velocity (FV) and symmetry in the MCA. Findings were compared with follow-up CT results and clinical outcomes using the European Stroke Scale. The study also tracked vessel recanalization and normalization of flow velocity during follow-up.

CE-TCCS provided adequate diagnosis in 74 of 90 patients (82%). MCA occlusion was detected in 20 patients, and reduced flow velocity was observed in 27. CTA confirmed MCA occlusion in 17 of these cases. One patient had a false-positive diagnosis of MCA occlusion. Five patients with MCA occlusion showed vessel recanalization during follow-up. Of 27 patients with reduced flow velocity, 15 showed normalization after the third examination. These patients had significantly better clinical outcomes (P<0.0001). MCA occlusion or reduced flow velocity in the first 12 hours was linked to larger infarctions (P<0.0001). These results suggest CE-TCCS is a reliable diagnostic tool for MCA occlusion and flow changes.

The authors propose that CE-TCCS is a reliable method for diagnosing MCA occlusion in patients with inadequate unenhanced TCCS. Their findings suggest that CE-TCCS can detect MCA occlusion or flow velocity changes in most patients. The method correlates well with CTA and follow-up CT results. Patients with MCA occlusion or reduced flow velocity had larger infarctions and worse outcomes. Normalization of flow velocity was associated with better clinical outcomes (P<0.0001). The researchers suggest that CE-TCCS may help identify patients who could benefit from thrombolytic therapy. They propose that this method provides valuable information about cerebral tissue status and prognosis. The study supports the use of CE-TCCS in acute stroke patients with poor conventional ultrasound results.