Comparison Between The Time-SLIP Images of Two Cases With Giant Arachnoid Cyst And Aqueduct Stenosis Under Neuroendoscope Assist

Ayako Horiba, Yasuo Aihara, Kentaro Chiba, Kayoko Abe, Shuuji Sakai, Takakazu Kawamata

Purpose : Cerebrospinal fluid (CSF) flow can be characterized by its speed and also qualitatively as laminar or turbulent. These characteristics depend on pressure and compliance in the CSF spaces, together with any propagated pulsations. By using the unenhanced time spatial labeling inversion pulse (T-SLIP) technique, it became possible to visualize CSF movement noninvasively, regardless of physiological conditions. We observed two cases with very similar pathology, which further on had very different clinical courses and we discuss the role of T-SLIP demonstrated CSF dynamics.

Methods: We had the opportunity to treat 2 patients who suffered from repeating headache episodes and diagnosed with arachnoid cysts in the left cerebellar hemisphere. Both cases were treated by surgery, performing cyst fenestrations. We performed T-SLIP examinations before and after surgery.

Results: Although both cases showed the same condition, T-SLIP results clearly differed after the operation. The first case showed substantial CSF outflow from the cyst on T-SLIP images and there was a good clinical outcome with cyst size reduction as seen on MRI images and confirmed by the disappearance of headaches. On the other hand, the case in which postoperative T-SLIP images showed restricted CSF movement needed a C-P shunt after the initial operation.

Conclusions: While still having limitations, T-SLIP method has the potential to estimate functionally not only for the current condition of new CSF paths, but suggest the future clinical course of these patients.