Leptomeningeal Enhancement on 3D-FLAIR MRI in Multiple Sclerosis: Systematic Observations in Clinical Practice.

BACKGROUND AND PURPOSE: Meningeal inflammation is implicated in cortical demyelination and disability progression in multiple sclerosis (MS). Gadolinium (Gd)-enhanced 3-dimensional (3D) FLAIR (fluid-attenuated inversion recovery) magnetic resonance imaging (MRI) can identify leptomeningeal enhancement (LME) in MS. Further characterization is needed to determine if LME is an imaging biomarker for meningeal inflammation. We sought to characterize the natural history of LME in the community setting, including persistence/resolution, effect of disease-modifying therapy, scanner variability, timing of acquisition, and imaging pitfalls that may lead to misinterpretation. METHODS: A total of 341 MRI exams with Gd-enhanced 3D-FLAIR were reviewed in MS and non-MS patients to determine frequency of enhancement by MS subtype and association with therapy. A phantom was used to assess scanner variability. Two MS patients with seven LME were imaged at four postinjection time points to generate time-intensity curves. Imaging pitfalls were compiled. RESULTS: A total of 16.6% (40/241) of MS patients revealed LME compared to 8% (8/100) in non-MS patients (P = .04). There was no association with MS subtype, therapy, or disease activity. Detection using General Electric's version of 3D-FLAIR (29%) was greater than with Siemen's 3D-FLAIR (12%) at 1.5T (Tesla) (P < .001). Lesions were generally stable but resolved in 2 patients following high-dose steroids. LME kinetics were heterogeneous, even within patients, without uniform optimal time for acquisition. Enhancement curves exhibited three different variations, similar to the two-compartment model. Imaging pitfalls included enhancements of uncertain biologic significance, cortical veins and anatomic structures, and imaging artifacts. CONCLUSIONS: Awareness of LME characteristics, variability with imaging parameters, and imaging pitfalls will facilitate determining the potential role as an imaging biomarker for meningeal inflammation.

Familial Kleine-Levin syndrome: two siblings with unusually long hypersomnic spells.

Kleine-Levin syndrome is a rare, sporadic disorder, with discrete spells of hypersomnolence occurring during adolescence, variously accompanied by megaphagia, behavioral changes, psychosis, and mild autonomic symptoms. Familial cases have not previously been reported. We describe 2 siblings who shared uncharacteristically prolonged episodes of hypersomnolence, and the HLA-DR2 haplotype. In one patient, levels of cerebrospinal fluid orexin (hypocretin) during an attack were normal. The presence of an increased sleep drive, despite the occurrence of large amounts of ostensibly restorative sleep, suggests the possible existence of a disorder of sleep satiety.

Isolated mononeuropathy multiplex--a rare manifestation of intravascular large B-cell lymphoma.

Intravascular large B-cell lymphoma, also known as angiotrophic large cell lymphoma, is a rare disorder where neoplastic lymphoid cells proliferate within the walls of small- to medium-sized blood vessels. Peripheral neuropathy and other neurological manifestations, including stroke and dementia, are common, but cases of isolated multiple mononeuropathies in the absence of systemic symptoms are distinctly rare. We present an unusual case of biopsy-proved angiotrophic large cell lymphoma presenting exclusively with multiple mononeuropathies.

Cryptococcal meningitis and sarcoidosis.

This report describes a patient with cryptococcal meningitis and newly diagnosed sarcoidosis not taking corticosteroids. Sarcoidosis is an independent risk factor for cryptococcal infection; most patients with sarcoidosis who develop cryptococcal infection are not on immunosuppressive drugs. Cryptococcal meningitis in sarcoid patients often presents clinically with non-specific features, and should be excluded in patients with sarcoidosis and neurological disturbances.