Diffusion-Weighted Imaging Patterns According to the Right-to-Left Shunt Amount in Cryptogenic Stroke

Area of Science:

• Neurology
• Cardiology
• Radiology

Background:

• Patent foramen ovale (PFO) is a suspected cause of cryptogenic stroke.
• Defining a
• true
• PFO-related stroke remains challenging.

Purpose of the Study:

• To evaluate diffusion-weighted imaging (DWI) findings in cryptogenic stroke patients.
• To correlate DWI findings with the amount of right-to-left shunt (RLS) measured by transcranial Doppler (TCD).

Main Methods:

• 100 consecutive cryptogenic stroke patients were assessed between October 2010 and 2018.
• RLS amount was categorized using International Consensus Criteria, with massive RLS defined as the highest category (Curtain pattern).
• DWI findings, including lesion location, vascular territory, and lesion patterns, were analyzed.

Main Results:

• PFO was present in 59 out of 100 patients.
• Massive RLS was significantly associated with cortical lesions (aOR 15.75), multiple territory involvement (aOR 5.24), and a higher number of DWI lesions (beta 0.713).
• Massive RLS showed inverse correlations with posterior circulation involvement (aOR 0.22) and fewer large DWI lesions (beta -0.328).

Conclusions:

• Massive RLS in cryptogenic stroke patients is linked to multiple, small, scattered cortical lesions on DWI.
• This specific DWI pattern strongly suggests that the stroke is related to a PFO.