Fluid Attenuated Inversion Recovery (FLAIR) Imaging in Neuropsychiatric Systemic Lupus Erythematosus

WILMER L. SIBBITT Jr, PAUL J. SCHMIDT, BLAINE L. HART, and WILLIAM M. BROOKS

ABSTRACT.

Objective. To compare fluid attenuated inversion recovery (FLAIR) imaging with proton density/T2 weighted (PD/T2) imaging in neuropsychiatric systemic lupus erythematosus (NPSLE). Magnetic resonance imaging (MRI) is commonly used to evaluate NPSLE. However, the specific role of FLAIR versus conventional PD/T2 methods in NPSLE remains uncertain.

Methods. We studied 28 patients with NPSLE classified using the 1999 American College of Rheumatology Case Definitions for NPSLE. NPSLE disease activity and brain injury were estimated with the neurologic components of SLEDAI and SLICC, respectively. Axial T1, PD/T2, and FLAIR MR images were obtained at 1.5 Tesla. Lesions visible on PD/T2 and FLAIR imaging were quantitated, classified, and the lesion conspicuity was determined. Statistical comparisons were then made between imaging techniques.

Results. FLAIR detected significantly more lesions than PD/T2 (p < 0.001), resulting in a 5% greater diagnostic sensitivity, but infarct, leukoencephalopathy, and normal from abnormal were similar between the 2 methods (p > 0.7). Numbers of lesions by FLAIR correlated closely with lesions by PD/T2 (r² = 0.97, p < 0.0001). Conspicuity of individual lesions by FLAIR was greater than by PD/T2 in cortical, subcortical, and periventricular locations (p < 0.01). Both FLAIR and PD/T2 observations were similarly associated with NPSLE activity and NPSLE brain injury (p < 0.02).

Conclusion. FLAIR is more sensitive and demonstrates greater lesional conspicuity than conventional PD/T2 in NPSLE. Lesions on FLAIR are more obvious and less likely to be confused with nonlesional structures, thus FLAIR images have obvious advantages for both clinical care and didactic rounds. FLAIR is a reasonable addition to a NPSLE MRI examination, and will increase diagnostic sensitivity by about 5%. (J Rheumatol 2003;30:1983-9)

Key Indexing Terms:

SYSTEMIC LUPUS ERYTHEMATOSUS
NEUROPSYCHIATRIC
NPSLE
T2
MAGNETIC RESONANCE IMAGING
FLAIR

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From the Departments of Internal Medicine, Neurology, Neurosciences, and Radiology, and the Clinical and Magnetic Research Center, The University of New Mexico Health Sciences Center, Albuquerque, New Mexico, USA.

Supported in part by the National Institutes of Health RO1-NS35708 (Dr. Sibbitt), RO1-NS39123, P20-RR15636, R21-NS/HD41390, R21-HD41237 (Dr. Brooks), and by a grant from The MIND Institute (Dr. Brooks).

W.L. Sibbitt Jr, MD, Professor, Departments of Internal Medicine and Neurology and Clinical and Magnetic Resonance Research Center; P.J. Schmidt, MD, Resident Physician, Department of Radiology; B.L. Hart, MD, Professor, Department of Radiology; W.M. Brooks, PhD, Director, Hoglund Brain Imaging Center, Professor, Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas.

Address reprint requests to Dr. W.L. Sibbitt Jr, Department of Internal Medicine, 5th Floor ACC, University of New Mexico Health Sciences Center, Albuquerque, NM 87131.

Submitted July 12, 2002; revision accepted February 6, 2003.

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