Lipomyelomeningocele: Pathology, Treatment, and Outcomes

A Review

Christina E. Sarris, B.S; Krystal L. Tomei, M.D., M.P.H; Peter W. Carmel, M.D; Chirag D. Gandhi, M.D.


Neurosurg Focus. 2012;33(4):e3 

In This Article

Specialized Testing

Additional specialized testing such as urodynamic function studies and neurophysiological monitoring may be beneficial in evaluation of these patients to assist with timing of surgical intervention. Neurophysiological monitoring is also beneficial intraoperatively to assist with preservation of functional spinal cord and nerve roots during initial surgery and during repeat detethering procedures. Specific nuances of intraoperative neurophysiological testing will be discussed in a later section.

Urodynamic testing includes invasive and noninvasive testing, both aimed at determining the functional status of the bladder. This testing includes assessment of detrusor function and external urethral sphincter activity, both of which can be compromised in patients with lipomyelomeningocele. Noninvasive urodynamic studies include uroflowmetry, which evaluates the flow pattern during urination, and bladder ultrasonography, which can evaluate the shape and size of the bladder, as well as the postvoid residual, which should be zero if there is no urological dysfunction. Invasive testing includes a cystometrogram, which requires catheterization with or without concurrent electromyography of the external sphincter. This test evaluates bladder capacity, compliance, continence, and emptying.[15] The assignment of a urodynamic score that incorporates the parameters of volume, compliance, detrusor activity, and bladder-sphincter synergy allows for a preoperative measure of overall urinary function, as well as the opportunity to compare overall function both pre- and postoperatively.[48]

Neurophysiological testing may be used preoperatively to assess neurological and urological function by way of assessing innervations, and may include somatosensory evoked potentials, motor evoked potentials, and electromyography. Anal sphincter electromyography has demonstrated 96% sensitivity in detecting patients with sphincter dyssynergia and 78% sensitivity in detecting bladder dysmotility. The addition of perineal evoked potentials increased the sensitivity of the combined testing for sphincter dyssynergia to 100% and bladder dysmotility to 86%.[63]