Diffusion Tensor Imaging of the Spinal Canal in Quantitative Assessment of Patients with Lumbar Spinal Canal Stenosis

Epidural pressure measurement using a fiber-optic sensor (proof-of-principle in vivo animal trial)

BACKGROUND

An increase in epidural pressure around the stenosis has been observed in patients with lumbar spinal stenosis (LSS) with positive signs of sedimentation or redundant nerve roots. Further analysis of the pressure conditions in the stenotic area would be of great interest. We hypothesized that it would be possible to determine the physiological parameters of the epidural pulse wave and its course in pathological stenosis as a basis for objective identification of LSS based on pressure using a new measuring method with continuous spatial and temporal resolution.

METHODS

We performed a single-case proof-of-principle in vivo animal trial and used a newly developed hybrid pressure-measurement probe with a fiber-tip Fabry-Pérot interferometer and several fiber Bragg gratings (FBG).

RESULTS

With reproducible precision, we determined the mean epidural pressure to be 7.5 mmHg and the peak-to-peak value to be 4-5 mmHg. When analyzing the pressure measured by an FBG array, both the heart and respiratory rates can be precisely determined. This study was the first to measure the pulse wave velocity of the cerebrospinal fluid pressure wave as 0.97 m/s using the newly developed pressure probe. A simulated LSS was detected in real time and located exactly.

CONCLUSIONS

The developed fiber-optic pressure sensor probe enables a new objective measurement of epidural pressure. We confirmed our hypothesis that physiological parameters of the epidural pulse wave can be determined and that it is possible to identify an LSS.

The current state of radiodiagnostics of degenerative changes in the lumbar spine (literature review)

Examination of the spine using radiological methods remains the most frequently conducted study in the outpatient practice of almost any radiologist. In most cases, changes in the spine are degenerative and dystrophic in nature. These changes in the spine are the leading cause of loss of activity among adults and the elderly, and cover a wide range of age-related structural changes. It is of great importance to understand the possibilities and limitations of radiological methods of diagnostics. The description of morphological changes observed in degenerative and dystrophic changes requires the use of unified terminology and classifications among clinicians and radiologists.The aim. To present modern concepts in the assessment of degenerative changes of the spine using radiological methods. A description of the standardized international nomenclature of intervertebral disc pathology and current classifications of spinal canal stenosis are presented.Material and methods. For literature search, we used electronic databases MEDLINE (PubMed), eLibrary, EMBASE and Cochrane Library with a selection of sources published from 2000 to 2021. We analyzed the works devoted to the diagnosis of degenerative changes in lumbar spine and to degenerative stenosis.Conclusion. The key to productive communication between physicians is the uniformity or standardization of terminology and definitions used. It is important that the protocol of description, its terms, semantic expressions be uniform and understandable to specialists who are involved in the diagnosis and treatment of the spine. Magnetic resonance imaging is a valuable method in the diagnosis of degenerative changes of the spinal column, but it has its limitations.

Lumbar Spinal Stenosis: Pathophysiology and Treatment Principle: A Narrative Review

Patients with lumbar spinal stenosis may exhibit symptoms such as back pain, radiating pain, and neurogenic claudication. Although long-term outcome of treatments manifests similar results for both nonsurgical and surgical treatments, positive effects such as short-term improvement in symptoms and decreased fall risk may be expected with surgery. Surgical treatment is basically decompression, and a combination of treatments can be added depending on the degree of decompression and the accompanying instability. Recently, minimally invasive surgery has been found to result in excellent outcomes in the treatment of lumbar spinal stenosis. Therefore, better treatment effects can be anticipated with an approach aimed at understanding the overall pathophysiology and treatment methods of lumbar spinal stenosis.