Tarlov Cyst Is Correlated with a Short Broad Terminal of the Thecal Sac

Abstract

In clinical practice, we noted that the end section of the thecal sac is apparently different in patients with Tarlov cyst compared with that of the normal population. We conducted this clinical study based on magnetic resonance imaging (MRI). Our study included 30 patients with Tarlov cyst and 30 healthy volunteers as the control. The L4, L5 cross-section areas, the L4, L5 anteroposterior diameters, and the terminal length of the thecal sac were measured from the lumbosacral spine MRI. The L4, L5 cross-section areas and the L4, L5 anteroposterior diameters are larger for the Tarlov cyst patients than the controls, but the terminal length of the thecal sac is shorter. The Tarlov cyst is correlated with a short broad end of the thecal sac. Possibly, this anatomical variant is a causative factor of Tarlov cyst.