Multiple spontaneous skull base cerebrospinal fluid leaks: some insights from an international retrospective collaborative study

Purpose: Spontaneous skull base cerebrospinal fluid leaks occurring without any apparent cause are rare. But those patients that present such leaks simultaneously, or successively, in multiple locations are even rarer. Given the rarity of this condition, we collected data from other groups in a multicentre study to reach an adequate number of patients and draw some preliminary considerations. Methods: We carried out a multicentre retrospective study on a cohort of patients treated at third level hospitals in Italy, Spain, United Kingdom and Greece for multiple spontaneous-CSF leaks and we compared them with a control group of patients treated for recurrent spontaneous-CSF leaks. Data regarding clinical aspects, radiological findings, surgical techniques and outcome were collected and preliminary considerations on the results were discussed. Results: A total of 25 patients presented multiple simultaneous spontaneous CSF leaks while 18 patients fit with the criteria of recurrent spontaneous CSF leaks. Data analysis was conducted separately. Conclusions: Our understanding of the pathogenesis of this condition is currently very limited. A causative role of IIH may be present but the differences that emerged from the comparison with patients with recurrent fistulas seem to promote the possible role of other cofactors. A longer follow-up period is needed, and, in our opinion, prospective and multicentre studies are the only solution to seriously deal with such a complex topic.