Study links MRI findings of secondary brain damage to worse outcomes in patients with lacunar stroke

Led by a team of researchers from the Row Fogo Centre for Research into Ageing and the Brain, the study suggests that these imaging markers are associated with worse functional outcomes and a higher risk of recurrent strokes.

Published in the Annals of Neurology, this study offers valuable insights into the progression of cerebral small vessel disease (SVD).

Lacunar strokes:

Lacunar strokes, commonly caused by SVD, occur when blood flow to a small area of the brain is blocked, resulting in a small subcortical infarct (a region of tissue death, or necrosis) visible on MRI. Over time, follow-up MRI scans often reveal new hyperintense areas around the site of the original infarct, referred to as “caps” (superior to the initial infarct) or “tracks” (inferior to the initial infarct, and extending along white matter tracts). While these changes are common, their clinical implications have been unclear.

What did the study investigate?

The study aimed to determine whether the development of these “caps” and “tracks” has specific clinical and imaging correlates and how they relate to patient outcomes. The researchers explored whether these markers could be linked to worse functional recovery, mobility, cognition, or the risk of recurrent cerebrovascular events one year after a lacunar stroke.

What did the researchers find?

Researchers analysed data from 185 participants with recent lacunar stroke who underwent baseline and follow-up MRI. Over the course of a year, around half (50.3%) of the patients developed “caps/tracks” on their MRI scans, typically appearing about 3-6 months after the initial stroke.

The study found that patients with larger initial infarcts, infarcts in white matter, higher baseline SVD burden, and evidence of diffuse microstructural damage in normal-appearing white matter were more likely to develop “caps” and/or “tracks”. Moreover, “caps” and “tracks” were linked to worse functional outcomes, including reduced mobility and slower gait speed.

The presence of these “caps” and “tracks” was also associated with a twofold higher risk of recurrent strokes or transient ischaemic attacks or MRI-proven incident infarcts. However, these markers were not significantly associated with cognitive impairment within the one-year follow-up period.

The researchers found that “caps” and “tracks” partially bridged the link between SVD burden and poorer functional outcomes, indicating that these markers might represent the brain's susceptibility to progressive SVD-related brain injury.

“This study offers novel insights into the clinical relevance of ‘caps/tracks’ in lacunar stroke with recent small subcortical infarcts”, said Dr Yajun Cheng, one of the authors. “This specific type of brain imaging change could serve as a potential intermediate biomarker of treatment efficacy to improve outcomes of lacunar stroke. If validated, they could facilitate the testing of targeted treatments in clinical trials focused on SVD-related stroke and its progression.”

Implications and next steps:

The study’s findings have potential implications for both clinical practice and future stroke research. For example, assessing “caps” and “tracks” on follow-up MRI scans could improve long-term prognostication for patients with lacunar stroke, helping clinicians identify those at higher risk of poor recovery or stroke recurrence.

Moreover, the study suggests that reducing “caps” and “tracks” could be an early marker of success in clinical trials testing treatments aimed at improving outcomes of lacunar stroke. Interventions targeting the progression of SVD could help mitigate these imaging changes, potentially improving long-term recovery.

This research highlights the importance of understanding secondary brain changes visible on MRI after lacunar stroke and their impact on patient outcomes. By identifying “caps” and “tracks” as markers of progressive brain damage, the study offers a new avenue for monitoring SVD progression and tailoring post-stroke care. 

Further research is needed to explore potential strategies to prevent or reduce these changes and improve outcomes for patients with SVD-related stroke.

To read the full publication, click here. 

To learn more about cerebral small vessel disease, click here. 

Full citation: 

Cheng, Y., Arteaga-Reyes, C., Clancy, U., Garcia, D. J., Valdés Hernández, M. D. C., Thrippleton, M. J., Stringer, M. S., Blair, G. W., Wiseman, S., Chappell, F. M., Zhang, J., Liu, X., Jochems, A. C. C., Maniega, S. M., Sakka, E., Bastin, M. E., Brown, R., Loos, C. M. J., Makin, S. D. J., Liu, M., … MSS‐2, MSS‐3 and the INVESTIGATE‐SVDs Study Group (2025). Clinical Relevance of 'Cap' and 'Track' Development after Recent Small Subcortical Infarct. Annals of Neurology, 10.1002/ana.27182. Advance online publication. https://doi.org/10.1002/ana.27182