Introduction
and Objectives:
Sacral root neuromodulation can be a
beneficial treatment option in patients suffering
from therapy-resistent detrusor instability
or detrusor hypocontractility.
The
implantable neuromodulation system as described
by Tanagho and Schmidt enables unilateral
sacral nerve stimulation. The electrode is
inserted unilaterally into the sacral canal
via the sacral foramen (S3). Reports have
been made on sacral neuromodulation failures
of up to 50% in patients undergoing this procedure.
We
preferred bilateral electrode implantation
in order to achieve better effectivity of
the chronic sacral neuromodulation.
Material
and Methods:
After
assessment of the beneficial effect by means
of PNE test, 20 patients (14 with detrusor
instability, 6 with hypocontractile detrusor)
underwent tailored laminectomy for bilateral
electrode placement. Minimally invasive laminectomy
was performed. The electrodes were bilaterally
positioned. Laminectomy allows optimum electrode
placement and fixation.
Results:
In
the patients with detrusor instability the
incontinence episodes were reduced from 7.2
to 1 per day and the bladder capacity improved
from 280 to 350 ml. In patients with hypocontractile
detrusor, the initial residual urine level
of 350 ml (180 to 468) dropped to 58 ml (38
to 79). Maximum detrusor pressure during micturition
rose from initially 12 cmH2O (8
to 15) to 34 cmH2O (28 to 45).
The average followup period was 13.5 months.
There was no sign of deterioration in the
effect of modulation in any of the patients.
Conclusions:
Bilateral electrode implantation results in
optimal neuromodulation in either hyper- or
hypocontractile detrusors.
