cranial venous outflow obstruction

INTRODUCTION: Similarities between chronic fatigue syndrome and idiopathic intracranial hypertension (IIH) invite speculation that they may be related. Cranial venous outflow obstruction plays a role in the development of IIH. Could it be a factor in chronic fatigue? This paper attempts to evaluate an investigative approach to chronic fatigue syndrome that allows for this possibility. METHODS: Since 2007, patients attending a specialist clinic at our institution diagnosed with chronic fatigue syndrome and with prominent headache have been offered CT venography, lumbar puncture and a trial of cerebrospinal fluid withdrawal looking for IIH. Also, if CT venography revealed focal narrowing of the jugular veins, patients were offered catheter cerebral venography and jugular venoplasty attempting to establish their clinical significance. RESULTS: In the 29 patients investigated to date, the mean cerebrospinal fluid (CSF) pressure was 19 cm H2O (range 12 – 41 cm H2O). Twenty-five patients responded positively to CSF withdrawal and in 5 the CSF pressures were high enough to allow an unequivocal diagnosis of IIH while in the remaining 20, symptoms improved with lumbar puncture even though CSF pressures were within the normal range. Twenty-one patients had focal narrowing of one or both internal jugular veins on CT venography. Fourteen of these have had jugular venoplasty, all of whom reported an improvement in symptoms afterwards lasting from a few minutes to more than 1 month. CONCLUSIONS: Chronic fatigue syndrome may represent an incomplete form of IIH. Cranial venous outflow obstruction deserves further investigation as a possible aetiological factor.