Does change of spinal diverticular size predict the site of <i>de novo</i> recurrent CSF-venous fistulas in patients with spontaneous intracranial hypotension?

We found that in one-third of patients a change in diverticular size was observed corresponding to the site of the <i>de novo</i> recurrent fistula. An increase in diverticular size could be explained by increased diverticular wall tension (law of LaPlace) and attenuation of the diverticular wall resulting in a higher likelihood of developing a CSF-venous fistula and a decrease in size could be explained by decompression of the diverticulum through the fistula. A change in size of meningeal diverticula may help guide the invasive myelographic studies necessary to locate CSF-venous fistulas.