Indications and Timings of Re-operation for Residual or Recurrent Hemifacial Spasm after Microvascular Decompression: Personal Experience and Literature Review

Abstract

We reviewed reports about the postoperative course of hemifacial spasm (HFS) after microvascular decompression (MVD), including in our own patients, and investigated treatment for delayed resolution or recurrence of HFS. Symptoms of HFS disappear after surgery in many patients, but spasm persists postoperatively in about 10–40%. Residual spasm also gradually decreases, with rates of 1–13% at 1 year postoperatively. However, because delayed resolution is uncommon after 1 year postoperatively, the following is advised: (1) In patients with residual spasms after 1 year postoperatively (incomplete cure) or who again experience spasm ≥ 1 year postoperatively (recurrence), re-operation is recommended if the spasms are worse than before MVD. (2) When re-operation is considered, preoperative magnetic resonance imaging (MRI) findings and intraoperative videos should be reviewed to ensure that no compression due to a small artery or vein was missed, and to confirm that adhesions with the prosthesis are not causing compression. If any suspicious findings are identified, the cause must be eliminated. Moreover, because of the risk of nerve injury, decompression of the distal portion of the facial nerve should be performed only in patients in whom distal compression is strongly suspected to be the cause of symptoms. (3) Cure rates after re-operation are high, but complications such as hearing impairment and facial weakness have been reported in 10–20% of cases, so surgery must be performed with great care.

Wide distribution of central myelin segment along the facial nerve might explain hemifacial spasm with distal nerve compression

“…These measurements correspond to most NVC sites of HFSs, which have been accepted as the sites where the rational pathogenetic mechanism is triggered. However, some subsequent reports have indicated that NVC in the distal cisternal portion of the facial nerve also causes HFS (Hatayama et al, 2015; Ryu et al, 1998; Son, Ko, & Choi, 2019). Thus, this hypothesis is still incomplete and further discussion is required.…”

Treatment of Trigeminal Neuralgia with “Microvascular Decompression Plus” Technique

“…However, TN recurs slightly more frequently than does hemifacial spasm. 4,12, 21,22 The reasons for recurrence or partial pain remission of TN are variable. Factors, such as Teflon granuloma formation and venous compression, have commonly been involved in the redevelopment of symptoms.…”

Hemifacial Spasm Caused by Vascular Compression in the Cisternal Portion of the Facial Nerve: Report of Two Cases with Review of the Literature

“…Recurrence represents symptoms reappearing postoperatively after a symptom-free interval of more than 1 year [34]. When there is no improvement or worsening of symptoms after one year postoperatively, it is called “incomplete cure” or persistence [34, 35]. Reasons for an unsuccessful MVD include incomplete decompression by not identifying the true culprit vessels, presence of a previously unidentified secondary offending vessel, or implant compression/migration against the facial nerve [36–38].…”