Robotic Automated TCD (raTCD) for Detecting Right-to-Left Shunt

At NeuraSignal, we are dedicated to transforming the diagnosis and management of complex neurological conditions through innovative technologies like the NG2 Intelligent Ultrasound. A recent study conducted by Dr. Ira Chang and colleagues at Swedish Medical Center in Englewood, Colorado, underscores the pivotal role of robotic automated Transcranial Doppler (raTCD/NG2) in detecting Right-to-Left Shunt (RLS) / Patent Foramen Ovale (PFO) and managing patients with ischemic stroke. This groundbreaking study was published in January 2025 highlighting the value of the integration of the NG2 platform into the stroke workflow.

Background

The evaluation of PFO within cryptogenic strokes population remains an important aspect of the stroke workup. Traditional diagnostic tools like transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) have limitations—TTE lacks sensitivity, TEE is invasive, and manual TCD requires skilled operators. NG2 offers a non-invasive, automated alternative with the potential to improve diagnostic workflows and outcomes.

Study Highlights

The study was a single-center retrospective cohort conducted at Swedish Medical Center from December 2021 to December 2022. It included 212 adult stroke or transient ischemic attack (TIA) patients. Robotic TCD findings were classified using the Spencer Logarithmic Scale (SLS) combined with the Risk of Paradoxical Embolism (RoPE) score to create the modified screening PFO-Associated Stroke Causal Likelihood (msPASCAL) classification.

Key Results

1. High RLS Detection Rate
   • 59% of patients were found to have RLS / PFO using the NG2, demonstrating its sensitivity and reliability. This is similar to what was found in the Rubin et al BUBL Study which reported 64% of the study population had a RLS / PFO.
2. RLS Severity Grading with SLS
   • 56% of RLS / PFO cases were graded as small (SLS 1-2), while 44% were graded as large (SLS 3-5).
   • Patients with large RLS were further classified as:
     • 44% Unlikely to have PFO.
     • 30.4% Possible PFO-related stroke.
     • 25.6% Probable PFO-related stroke.
3. Workflow Integration
   • This study demonstrated that the NG2 integrated well within the stroke workflow of a Comprehensive Stroke Center and produced clinically significant results compared to standard of care TTE and TEE.

Discussion

This study validates the use of the NG2 as a feasible, reliable, and non-invasive tool for RLS detection and PFO evaluation. By combining SLS with RoPE scores to generate the msPASCAL classification, clinicians gain actionable insights to guide further management. Importantly, NeuraSignal’s NG2 outperformed traditional methods in detecting RLS in challenging cases, such as sedated patients or those with small shunts.

Implications for Patient Care

The findings reinforce NeuraSignal’s mission to provide cutting-edge tools that improve diagnostic accuracy and streamline workflows. With devices like the NG2 Intelligent Ultrasound, healthcare providers can leverage robotic automation to deliver faster, more precise diagnoses, improving outcomes for patients with cryptogenic strokes.

Conclusion

As demonstrated by the Swedish Medical Center study, robotic automated TCD represents the future of stroke diagnostics. By enabling accurate RLS detection and PFO management, NeuraSignal’s NG2 empowers clinicians to make more informed decisions, ultimately improving patient care and outcomes. Read the current abstract published on Frontiers HERE.