Fatty Filum Terminale on MRI

Abstract

Background: Fatty filum terminale is sometimes demonstrated on MRI incidentally. It is considered as one of the causes in tethered cord syndrome (TCS). Location and the size of fatty filum are considered as the important factors for TCS. But there was no report on the disc degeneration according to the tension of fatty filum. Purpose: To discuss the fatty filum terminale which is incidentally demonstrated on MRI concerning the causes of TCS Study Design/Setting: Relations between MRI findings (location, size of fatty filum and the disc degeneration) and clinical symptoms Methods: Lumbar MR images in 535 patients were reviewed. Fatty filum terminale was found in seven patients using magnetic resonance images (MRI: GE, Signa excite, 1.5T). The location, size of fatty filum terminale and the clinical symptoms were evaluated in 7 patients. The disc degenerations were also evaluated in 7 patients. Results: Fatty filum terminale was found in 7 of 535 patients (1.3%) on MRI. The distance between the tip of conus and the fatty filum was 23.3mm (8-45mm). The mean diameter of the fatty filum was Φ2.57 (1-4) mm. Six of seven patients had disc degeneration on MRI. And the fatty filum were observed as a slacken strand on MRI. There were no clinical symptoms related to fatty filum terminale with degenerated discs. Conclusion: The fatty filum terminale may cause TCS even in elder patients. Thus the attention should be paid to the location and the diameter of the fatty terminale if it is demonstrated on MRI. And also we suggest that the attention should be paid the disc generations and the tension of terminale itself.