Objectives The techniques currently used to detect a cerebrospinal fluid (CSF) leak are an indium radionucleotide scan and a CT scan with intrathecal iodinated contrast agent. They have a low spatial and temporal resolution and are unpleasant for the patient. This open-label prospective observational cohort study was designed to investigate the feasibility, success ratio, complications and therapeutic consequences of MRI with gadolinium administered by lumbar puncture to detect a CSF leak.

Methods Patients were selected with either confirmed liquorrhoea, recurrent bacterial meningitis, or symptoms, and MRI findings of spontaneous intracranial hypotension. High-resolution T1 weighted MRI with fat suppression of the spinal column at 1 h and of the brain at 6 and 24 h postinjection of 0.5 ml of gadolinium were performed.

Results 27 patients were included. The clinically suspected CSF leak was found in six of eight patients with liquorrhoea, three of five patients with recurrent bacterial meningitis and nine of 14 patients with spontaneous intracranial hypotension. The procedure was easy to perform and generally well tolerated. One patient developed streptococcal meningitis in the hours following the procedure but recovered completely with antibiotic treatment. 17 of 18 patients in whom a dural defect was found underwent surgery. All patients became symptom-free after closure of the dural leak.

Conclusions Spinal cord and brain MRI after intrathecal gadolinium injection is an easy-to-perform and accurate technique for detection of a dural defect with excellent anatomical detail.