NLS diagnostics of spinal degenerative changes is presented as a noninvasive approach for examining the spine and spinal cord. The described NLS method is intended to provide information about degenerative changes of the lumbar spine, intervertebral discs, vertebral bodies, spinal canal, and surrounding structures.

According to the reported investigation, NLS diagnostics of spinal degenerative changes was performed using a Metatron-4025M system equipped with a 4.9 GHz digital trigger sensor. A total of 1,217 patients with degenerative changes in the lumbar region of the spine were examined.

The reported advantages of NLS diagnostics of spinal degenerative changes include noninvasive imaging, different imaging orientations, and virtual visualization of radicular canals and paravertebral structures.

NLS Diagnostics of Spinal Degenerative Changes and Disc Degeneration

In the reported patient group, intervertebral disc degeneration was identified in 87% of cases. The earliest described degenerative change was a hyperchromous lesion in the region between the nucleus pulposus and the fibrous annulus.

The study also described increased chromogenic density of the signal from the bone marrow adjacent to the vertebral bodies. Based on the reported findings, three degrees of degenerative changes were distinguished according to the intensity of the process.

Degree 1 Degenerative Changes

In the first degree, a hyperchromous zone evaluated at 4–5 points on Flandler’s scale was reported in 90 patients.

The conventional radiographs reportedly did not demonstrate changes in these patients. The authors associated these findings with the formation of fibrovascular tissue and its penetration into the bone marrow.

The reported histograms showed spectral similarity to the reference standard described as “intervertebral osteochondrosis,” with D values ranging from 0.396 to 0.425.

Degree 2 Degenerative Changes

The second degree was characterized by a hyperchromous response evaluated at 5–6 points on Flandler’s scale. This finding was reported in 215 patients.

Conventional radiographs reportedly did not demonstrate changes at this stage. The article describes evidence suggesting replacement of fatty bone marrow with red bone marrow, sometimes accompanied by enlargement of trabeculae.

The reported spectral similarity to the reference standard “intervertebral osteochondrosis” was more pronounced, with D values ranging from 0.246 to 0.360.

Degree 3 Degenerative Changes

The third degree was described as an evident hyperchromous response reaching 6 points on Flandler’s scale.

This finding corresponded in the report to advanced sclerosis of the vertebral bodies. Secondary findings, including local bulging and vertebral osteophytes, were also described in association with advanced degenerative disc changes.

The reported similarity to the reference standard “osteochondrosis” ranged from D 0.152 to 0.218.

NLS Diagnostics of Disc Protrusion

One of the reported applications of NLS diagnostics of spinal degenerative changes was the differentiation of intervertebral disc protrusion and prolapse.

A disc protrusion was described as bulging of disc tissue beyond the posterior outline of the vertebral body and into the spinal canal.

According to the article, the fibrous annulus remains intact in a protrusion, although it may become considerably thinner. The NLS examination reportedly showed a zone of slight structural change evaluated at approximately 3–4 points.

The nucleus pulposus may shift dorsally and extend toward the intervertebral foramina. When the foraminal structures are compressed, irritation of the nerve root may occur.

The article states that an uninvolved nerve root normally produces a moderate response, while a compressed nerve root may demonstrate a more pronounced hyperchromous response.

Disc protrusion was reported in 729 patients in the described investigation.

NLS Diagnostics of Disc Prolapse

NLS diagnostics of spinal degenerative changes was also used in the reported investigation to assess disc prolapse.

The article describes prolapse as occurring when fibers of the fibrous annulus rupture and the nucleus pulposus extends beyond its normal position. If the longitudinal ligament also ruptures, disc material may extend into the cerebrospinal canal.

The longitudinal ligaments were described as well-defined hyperchromous band-like structures adjacent to the vertebral bodies and fibrous annulus.

An extraligamentary disc prolapse may migrate in either a cranial or caudal direction. When displaced disc material loses contact with the original disc, it may become a sequester.

The reported NLS examination detected disc prolapse in 445 patients.

Lumbar Disc Herniation Findings

In 68% of the reported cases, intervertebral disc herniation was associated with other degenerative and dystrophic spinal changes at the same level.

The reported distribution of disc herniation was:

• L4–L5: 83%
• L5–S1: 15%
• L3–L4: 2%

Multiple affected discs were reported in 50 patients.

A total of 196 patients underwent surgery. Among these patients, 114 had lateral hernias, 76 had median-lateral hernias, and 6 had median hernias. Five patients underwent surgery for recurrent herniation.

The NLS examination reportedly identified extraligamentary sequestered herniation in 38 patients and intradural herniation in 3 patients. Multiple sequesters were detected in five patients.

Clinical Symptoms and Spinal Disc Changes

The article reports that clinical symptoms associated with intervertebral disc prolapse varied considerably and did not always correspond to the size of the lesion.

Some median disc protrusions were reported without significant clinical symptoms. Conversely, small sequestered hernias could produce clinical symptoms comparable to those associated with larger sequesters.

This finding highlights the importance of considering both imaging findings and clinical presentation when evaluating patients with suspected spinal degenerative disease.

Imaging Planes in NLS Diagnostics

For suspected disc herniation, the article recommends examination in at least two planes:

• Sagittal plane
• Paraxial plane parallel to the disc

Additional projections may also be used depending on the suspected pathology.

Sagittal images were reported to demonstrate median intervertebral disc prolapses clearly. They can also provide information regarding the size of the intervertebral foramina, the cerebrospinal canal, and the vertebral bones.

Paraxial virtual models were described as useful for differentiating structures within the nucleus pulposus and fibrous annulus.

Sagittal and Paraxial NLS Imaging

Sagittal imaging has several reported advantages in the assessment of disc prolapse and spinal anatomy. It can help demonstrate the relationship between the disc, spinal canal, intervertebral foramina, and vertebral structures.

Paraxial virtual models can provide additional visualization of the nucleus pulposus and fibrous annulus. According to the article, these models may help distinguish between disc protrusion and processes involving annular rupture.

Frontal imaging has limitations in assessing the nucleus pulposus and fibrous annulus. Therefore, the article describes the use of paraxial virtual models as an additional imaging approach.

NLS Diagnostics and Spinal Degenerative Disease

Overall, the described NLS diagnostics of spinal degenerative changes focuses on evaluating degenerative disc disease, disc protrusion, disc prolapse, herniation, vertebral changes, and related spinal structures.

The investigation included a large patient group and compared NLS findings with other diagnostic procedures in selected patients, including CT and myelography.

The reported findings suggest that NLS was investigated as a method for visualizing degenerative changes of the spine and intervertebral discs. However, the clinical interpretation of spinal imaging should be considered together with the patient’s symptoms, physical examination, and established diagnostic methods.

Conclusion

NLS diagnostics of spinal degenerative changes was described in this study as a noninvasive imaging approach for evaluating degenerative changes of the lumbar spine.

The reported examination covered intervertebral disc degeneration, disc protrusion, disc prolapse, herniation, sequestered disc material, vertebral changes, and spinal canal structures.

The study also described the use of sagittal and paraxial imaging planes for evaluating suspected disc pathology. These findings provide the basis for further discussion of the potential role and limitations of NLS imaging in the assessment of spinal degenerative disorders.