Abstract
With aging societies, chronic spinal cord compression such as degenerative cervical myelopathy (DCM) is becoming an increasingly prevalent condition. In DCM, a collection of age-related pathologies leads to the narrowing of the cervical spinal canal and ultimately chronic spinal cord compression. DCM is a disabling and painful disorder that may progress to spinal cord injury (SCI) if not treated in time. In these patients, spinal cord compression is a main contributor to cerebrospinal fluid (CSF) space obstruction and subsequent spinal cord damage. Thus, timely and sufficient surgical decompression is a critical objective. Much of the literature is centered on surgical timing. However, a precise quantification of the degree of cord compression has yet to be established. In addition, DCM is plagued with the issue misdiagnosis which merely delays proper treatment and sufficient recovery.
Spinal stenosis causes a subdivision in the CSF space of above and below the site of compression. Increased resistance to CSF flow through spinal stenosis may result in altered CSF pressure (CSFP) dynamics compared to physiological conditions. It is hypothesized that monitoring of CSFP dynamics can be a valuable tool for both diagnosis and treatment of spinal cord compression. To this end, data were acquired from patients in various cohorts, including lumbar CSFP obtained at bedside in patients with DCM (N = 11) and SCI (N = 13), and ranges for unrestricted CSFP dynamics for comparison in patients without spinal cord compression (N = 14). Data were analyzed with respect to selected features, including mean CSFP and peak-to-valley CSFP amplitude (CSFPp). Moreover, Queckenstedt’s test (QT) was reintroduced as an additional maneuver to inform on the compliance of the craniospinal compartment.
Following the acquisition of a range of CSFP metrics in a healthy cohort at resting state and during QT, a valuable baseline was established to be further compared with findings in patients with cervical spinal canal stenosis. It was shown that disturbed CSFP dynamics are clearly distinguishable in the DCM and SCI cohort with ambiguous cord compression of unclear significance. CSFP monitoring complements findings from the more common diagnostic tools, i.e., neurophysiological tests and imaging. In conclusion, CSFP dynamics measured below the site of compression provide a quantitative measure for the degree of spinal cord compression, proving their potential as a biomechanical marker for the quantification of spinal cord compression. This could ultimately improve the diagnostic work-up and patient recovery.
Kheram, Najmeh