Array-Based Beamforming to the Vertebral Canal: Demonstration of Feasibility

The internal vertebral venous plexus (IVVP) is a thin-walled, valveless venous network that is located inside the vertebral canal, communicating with the cerebral venous sinuses. The objective of this study was to perform a morphometric analysis of the IVVP, dural sac, epidural space and vertebral canal between the L1 and L7 vertebrae with contrast-enhanced computed tomography (CT). Six clinically healthy adult dogs weighing between 12 kg to 28 kg were used in the study. The CT venographic protocol consisted of a manual injection of 880 mgI/kg of contrast agent (587 mgI/kg in a bolus and 293 mgI/mL by continuous infusion). In all CT images, the dimensions of the IVVP, dural sac, and vertebral canal were collected. Dorsal reconstruction CT images showed a continuous rhomboidal morphological pattern for the IVVP. The dural sac was observed as a rounded isodense structure throughout the vertebral canal. The average area of the IVVP ranged from 0.61 to 0.74 mm2 between L1 and L7 vertebrae (6.3–8.9% of the vertebral canal), and the area of the dural sac was between 1.22 and 7.42 mm2 (13.8–72.2% of the vertebral canal). The area of the epidural space between L1 and L7 ranged from 2.85 to 7.78 mm2 (27.8–86.2% of the vertebral canal). This CT venography protocol is a safe method that allows adequate visualization and morphometric evaluation of the IVVP and adjacent structures.

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Fallacies of the Present Definition, Nomenclature, and Classification of the Stenoses of the Lumbar Vertebral Canal

Spine ◽

10.1097/00007632-197612000-00006 ◽

1976 ◽

Vol 1 (4) ◽

pp. 217-225 ◽

Cited By ~ 45

Author(s):

HENK VERBIEST

Keyword(s):

Vertebral Canal

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Residual herniated disc material following hemilaminectomy in chondrodystrophic dogs with thoracolumbar intervertebral disc disease

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-11-05-0075 ◽

2012 ◽

Vol 25 (02) ◽

pp. 109-115 ◽

Cited By ~ 19

Author(s):

M. Thomas ◽

J. M. Weh ◽

J. Bleedorn ◽

K. Wells ◽

W. J. Roach

Keyword(s):

Intervertebral Disc ◽

Herniated Disc ◽

Intervertebral Disc Disease ◽

Disc Disease ◽

Vertebral Canal ◽

Telephone Interviews ◽

Disc Material ◽

Long Term Follow Up

SummaryObjective: To evaluate the presence of residual disc material within the vertebral canal following hemilaminectomy in chondrodystrophic dogs with thoracolumbar intervertebral disc disease.Methods: Forty dogs were treated by hemilaminectomy. Computed tomography was performed preoperatively and immediately postoperatively. The vertebral canal height, width, area, and herniated disc material area were measured. Maximum filling percentage (MFP), residual disc percentage (RDP), maximum residual filling percentage (MRFP), and residual filling percentage (RFP) were calculated. Clinical outcome was determined by telephone interviews.Results: Residual disc material was present in 100% of the dogs. Mean MFP = 55.4% (range 25.9–82.3%; median 56.9%). Mean RDP = 50.3% (range 2.6–155.8%; median 47.9%). Mean MRFP = 30.8% (range 4.9–60%; median 30.1%). Mean RFP = 19.8% (range 4.8–45%; median 19.0%). All dogs were ambulatory with voluntary urination at the long-term follow-up (range: 88–735 days).Clinical significance: Residual disc was present in all dogs following hemilaminectomy for intervertebral disc disease. Residual disc was not associated with failure to achieve functional recovery in these cases.

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The profile of the spinal column in subjects with lumbar developmental spinal stenosis

The Bone & Joint Journal ◽

10.1302/0301-620x.103b4.bjj-2020-1792.r1 ◽

2021 ◽

Vol 103-B (4) ◽

pp. 725-733

Author(s):

Marcus Kin Long Lai ◽

Prudence Wing Hang Cheung ◽

Dino Samartzis ◽

Jaro Karppinen ◽

Kenneth M. C. Cheung ◽

...

Keyword(s):

Logistic Regression ◽

Spinal Stenosis ◽

Vertebral Body ◽

Spinal Canal ◽

Facet Joint ◽

Spinal Column ◽

Stepwise Logistic Regression ◽

Diagnostic Study ◽

Vertebral Canal ◽

Dural Sac

Aims The aim of this study was to determine the differences in spinal imaging characteristics between subjects with or without lumbar developmental spinal stenosis (DSS) in a population-based cohort. Methods This was a radiological analysis of 2,387 participants who underwent L1-S1 MRI. Means and ranges were calculated for age, sex, BMI, and MRI measurements. Anteroposterior (AP) vertebral canal diameters were used to differentiate those with DSS from controls. Other imaging parameters included vertebral body dimensions, spinal canal dimensions, disc degeneration scores, and facet joint orientation. Mann-Whitney U and chi-squared tests were conducted to search for measurement differences between those with DSS and controls. In order to identify possible associations between DSS and MRI parameters, those who were statistically significant in the univariate binary logistic regression were included in a multivariate stepwise logistic regression after adjusting for demographics. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported where appropriate. Results Axial AP vertebral canal diameter (p < 0.001), interpedicular distance (p < 0.001), AP dural sac diameter (p < 0.001), lamina angle (p < 0.001), and sagittal mid-vertebral body height (p < 0.001) were significantly different between those identified as having DSS and controls. Narrower interpedicular distance (OR 0.745 (95% CI 0.618 to 0.900); p = 0.002) and AP dural sac diameter (OR 0.506 (95% CI 0.400 to 0.641); p < 0.001) were associated with DSS. Lamina angle (OR 1.127 (95% CI 1.045 to 1.214); p = 0.002) and right facet joint angulation (OR 0.022 (95% CI 0.002 to 0.247); p = 0.002) were also associated with DSS. No association was observed between disc parameters and DSS. Conclusion From this large-scale cohort, the canal size is found to be independent of body stature. Other than spinal canal dimensions, abnormal orientations of lamina angle and facet joint angulation may also be a result of developmental variations, leading to increased likelihood of DSS. Other skeletal parameters are spared. There was no relationship between DSS and soft tissue changes of the spinal column, which suggests that DSS is a unique result of bony maldevelopment. These findings require validation in other ethnicities and populations. Level of Evidence: I (diagnostic study) Cite this article: Bone Joint J 2021;103-B(4):725–733.

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