Diffusion kurtosis imaging in patients with tissue-negative transient ischemic attack

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Transient ischemic attack (TIA) diagnosis can be challenging, with many patients lacking evidence on conventional diffusion-weighted imaging (DWI).
• This diagnostic gap necessitates advanced imaging techniques to identify at-risk individuals.

Purpose of the Study:

• To evaluate the additional diagnostic value of diffusion kurtosis imaging (DKI) in TIA patients with normal DWI findings.
• To determine if DKI can predict stroke recurrence in this patient cohort.

Main Methods:

• Prospective study of 179 suspected TIA patients undergoing MRI (DWI and DKI) within 24 hours of symptom onset.
• Included patients had confirmed TIA, no stroke history, and no DWI lesions at baseline.
• Follow-up DWI was performed within 90 days to assess stroke recurrence.

Main Results:

• Of 98 patients with normal baseline DWI, 31 (31.6%) showed positive findings on DKI.
• DKI abnormalities correlated with clinical symptoms in 93.5% of positive cases.
• Recurrent stroke occurred in 14.3% of patients; it was significantly higher in the DKI-positive group (29.0% vs. 7.5%, p=0.01).
• Baseline DKI abnormality was associated with stroke recurrence, with 8 of 9 DKI-positive stroke patients developing new lesions in the corresponding arterial territory.

Conclusions:

• Diffusion kurtosis imaging (DKI) offers significant added diagnostic value in TIA patients with normal DWI.
• DKI findings can predict the risk of recurrent stroke in TIA patients with initially negative DWI scans.
• DKI may help identify TIA patients who require closer monitoring or more aggressive management to prevent future strokes.