Objective: This article aims to evaluate the outcome after endoscope-assisted microvascular
decompression for hemifacial spasm.
Materials and Methods: A total of 463 patients (283 females, 180 males, mean age: 55 years) suffering from
hemifacial spasm underwent an endoscope-assisted microvascular decompression via a
lower retrosigmoid approach. The spasm was left in 281 patients and right in 182 patients.
The mean duration of the symptoms was 7.8 years.
Results: The use of the endoscope enabled a perfect inspection of the facial nerve exit zone.
There was no endoscope-related nerve or vessel injury and morbidity, respectively.
In all patients, the vascular compression sites were identified without any retraction
with the aid of a 45° endoscope. In most patients, we found a typical arterial compression
of the root exit zone of the facial nerve. The most frequent offending vessel was
PICA (156) and AICA (122). In one patient, we found a purely venous compression, in
three patients a compression by arachnoid bands. The pattern of improvement varied.
More than half of the patients (262) were spasm-free immediately after surgery. However,
many patients needed more time to become spasm-free. After 18 months (n = 319), 90.6% of the patients were spasm-free or have rarely mild spasms (>90% improvement).
In 21 patients, the spasm improved by at least 50%. In nine patients, there was no
significant improvement. In all of these patients, we found anatomic anomalies or
a severe compression with morphological damage of the facial nerve. One patient died
due to herpes encephalitis 14 days after surgery. Complications included meningitis
(0.6%), CSF fistula (3.0%), hearing loss (14.5%), facial palsy mostly delayed (8.2%),
vertigo (2.4%), and hoarseness (3.2%). We observed permanent neurological deficits
such as anacusis (2.8%), hypacusis (3.9%), facial palsy (HB: 2–3) (1.1. %), and vertigo
(0.9%).
Conclusion: The endoscope-assisted microvascular decompression technique provides a high success
rate with acceptable complications. The use of endoscopes improves the visualization
of the nerve in its entire course through the subarachnoid space without any retraction.
Especially in compression sites at the pontomedullary sulcus, the endoscope was helpful
to visualize the compression site.
