3D T2-weighted turbo spin-echo MR sequence for identifying cerebrospinal fluid leak after endoscopic endonasal pituitary surgery

This study aimed to assess the efficacy of MR images with 3D T2-weighted turbo spin-echo (3D T2-TSE) sequences for early identification of postoperative cerebrospinal fluid (CSF) leaks. We analyzed the medical records and radiological reports for 72 consecutive patients who underwent an endoscopic endonasal approach for sellar and parasellar lesions between April 2009 and December 2010. Patients were 38 men and 34 women with a mean age of 46.4 years. All underwent MR scanning within 2 postoperative days, which included 3D T2-TSE sequences as well as a conventional T2-weighted (T2W) protocol. Sequence accuracy in predicting postoperative CSF leaks was assessed for sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). A postoperative CSF leak was confirmed in 6 of 72 patients (8.3 %). On immediate postoperative MR images, 39 patients were suspicious for CSF leaks on conventional T2W sequences, while 18 patients on 3D T2-TSE. The 3D T2-TSE imaging had superior specificity and PPV (50 % vs. 81.8 %, 15.4 % vs. 33.3 %), while there was no difference in sensitivity and NPV compared with conventional T2W sequences. Compared to the conventional T2W protocol, MR imaging with the 3D T2-TSE protocol provides differential images around the sellar area with improved specificity and PPV for the detection of postoperative CSF leaks.