A new MR radiological sign in HaNDL syndrome. A case report.

Background: One of the classical diagnostic criteria of the syndrome of transient headache and neurologic deficits with cerebrospinal fluid lymphocytosis (HaNDL syndrome) is the normality of imaging studies except from some reversible alterations as leptomeningeal enhancement or focal hypoperfusion.

Case: We present a 41 year-old man who abruptly started with a set of right parietal symptoms, meeting the diagnostic criteria for HaNDL syndrome. An electroencephalographic record showed a slowing of the right hemisphere. MR susceptibility weighted sequences demonstrated a reduced venous signal in the symptomatic hemisphere, unlike other transient disorders as migraine aura where an opposite pattern with prominence of the venous structures in the symptomatic hemisphere has been reported. This sign could reflect a decrease in metabolic demands or a fail in oxygen employment by the affected tissue.

Conclusion: To our knowledge, this finding has not been described yet, and it may provide a new insight on the pathogenesis of HaNDL syndrome.