Case report of recurrent hemifacial spasm attributed to over-impaction with Teflon sponge

Abstract

Background: Hemifacial spasm (HS) is a muscular disorder frequently exacerbated by arterial compression amenable to surgical intervention through microvascular decompression (MVD). Recurrence is a known cause and warrants investigation.

Case description: A 65-year-old woman presented with the left HS of 7 years duration. Her symptoms were initially well controlled with botulinum toxin injections. However, these injections eventually lost their effectiveness, necessitating MVD. At surgery, the anterior inferior cerebellar artery was indenting the facial nerve at its root entry zone. This was carefully dissected away, and several Teflon (polytetrafluoroethylene) felt pledgets were used for decompression. Postoperatively, the patient reported great improvement of her symptoms for 3 months. Gradually her spasms returned, intermittently at first, until finally they became persistent 6 months postoperatively. An MRI was obtained showing elevation and posterior displacement of the VII-VIII complex by the pledgets. After failing to improve, the patient opted for reoperation 10 months after initial MVD. At surgery, the Teflon pledgets were displacing the VII-III nerves posteriorly and superiorly. The Teflon pledgets were dissected free, and the nerve dis-impacted. On her postoperative visit 1 year later, she is spasm free, subjectively, and objectively.

Conclusion: This case illustrates the value of re-imaging recurrent HS, and re-exploration with a favorable rkesult.

Keywords: Hemifacial spasm; Microvascular decompression; Teflon.

Figure 1:

Preoperative T2-weighted MRI shows the left anterior inferior cerebellar artery (arrow) coursing perpendicular to and contacting the VII-VIII complex.

Figure 2:

At surgery (a), a vascular loop, most likely anterior inferior cerebellar artery (a with white circle), is seen coursing inferior to the VII-VIII complex (VII-VIII) and displacing it rostrally. Several Teflon pledgets (T) are inserted at the site of conflict, separating the artery from the nerves (b).

Figure 3:

The VII-VIII complex (arrow) is now displaced posteriorly and superiorly by the Teflon pledgets placed beneath the nerve complex.

Figure 4:

The Teflon (T) sponges are found displacing the VII-VIII complex (VII-VIII) posteriorly (a). The Teflon is dissected free of the nerves and the nerves decompressed with the trigeminal nerve (V) seen superiorly (b). A significant amount of Teflon sponge is removed (c).