Contrast-enhanced T2-FLAIR MR imaging in patients with uveitis

Area of Science:

• Ophthalmology
• Radiology
• Medical Imaging

Background:

• Uveitis is a pathological inflammatory condition affecting the uveal tract of the eye.
• Accurate MRI findings are crucial for diagnosing and understanding the extent of uveitis.
• Conventional MRI sequences may have limitations in detecting subtle inflammatory changes.

Purpose of the Study:

• To identify specific MRI findings indicative of uveal tract inflammation.
• To evaluate the diagnostic performance of post-contrast T2-FLAIR sequences compared to T1-weighted sequences in uveitis patients.
• To assess the prevalence and location of uveal tract enhancement in a small cohort of uveitis patients.

Main Methods:

• Retrospective case series of five patients with a clinical diagnosis of uveitis.
• MRI scans were performed using a 1.5 T scanner, with additional 3 T reference scans for control subjects.
• Analysis focused on post-contrast T2-FLAIR fat-suppressed images and T1-weighted images for enhancement patterns.

Main Results:

• All five patients exhibited uveal tract enhancement on post-contrast T2-FLAIR images.
• Only 40% of patients showed enhancement on T1-weighted images, indicating higher sensitivity for T2-FLAIR.
• Enhancement patterns varied (anterior, pan-uveal, posterior), with some patients showing vitreous or retrobulbar fat enhancement.

Conclusions:

• Post-contrast T2-FLAIR MRI is effective in revealing uveal tract enhancement, increased vitreous signal, and retrobulbar fat changes in uveitis.
• The sensitivity of post-contrast T2-FLAIR for detecting uveitis appears higher than conventional T1-weighted imaging in this series.
• Bilateral uveal tract enhancement requires careful interpretation due to its presence in other conditions and healthy subjects at 1.5 T; it's a normal finding at 3 T.