[Magnetic resonance imaging versus DR for whole spine imaging in patients with degenerative spinal disease].

OBJECTIVE: To assess the quality of whole spine images obtained by DR and magnetic resonance imaging (MRI) and analyze the whole spinal imaging sagittal parameters for standing DR and supine MRI. METHODS: Sixty-one patients aged 49.9∓17.6 years with degenerative spinal disease underwent both standing DR and supine MRI of the whole spine from November, 2010 to March, 2016. The image quality was retrospectively reviewed, and the cervical lordosis (CL), thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), and sagittal vertical axis (SVA) were measured on the whole spinal lateral DR and middle sagittal MR images. RESULTS: Both the DR and MR whole spine images had a high quality (100%). The CL, TK, LL, SS, and SVA measured were 28.37mnplus;10.91 °, 29.98mnplus;8.96 °, 45.61mnplus;12.46 °, 34.38mnplus;9.05 °, and 17.20mnplus;26.39 mm on DR images and were 24.34mnplus;9.01 °, 21.22mnplus;8.13 °, 41.45mnplus;12.17 °, 37.45mnplus;8.19 °, and 36.51mnplus;12.44mm on MR images, respectively, showing significant differences in the measurements between the two modalities (P=0.000, 0.000, 0.000, 0.001, and 0.007, respectively). The correlation coefficient between DR and MR images for CL, TK, LL, SS, and SVA were 0.69, 0.68, 0.72, 0.51, and 0.27 (P=0.000, 0.000, 0.000, 0.000, and 0.034, respectively). CONCLUSION: Both standing DR and supine MR whole spine imaging can provide high-quality images. The CL, TK, LL, SS, and SVA measured on supine MR whole spine images are correlated with those on standing DR images but differ obviously. Supine MR imaging can not substitute standing DR examinations, and comprehensive assessment of degenerative spinal disease needs the combination of the two imaging techniques.

Establishing a disc degeneration model using computed tomography-guided percutaneous puncture technique in the rabbit.

BACKGROUND: Various animal models have been developed to investigate the complex mechanisms leading to intervertebral disc disorders and to evaluate the different therapeutic options. The needle puncture technique is commonly used to induce intervertebral degeneration in animal models. The present study aimed to establish a rabbit model of intervertebral disc degeneration using a simple, minimally invasive procedure. METHODS AND MATERIALS: The animal model was created in the rabbit using computed tomography-guided percutaneous puncture technology. An 18-gauge needle was used to induce a disc injury with a 5-mm puncture depth. Radiographic, histologic, and biochemical analyses and magnetic resonance imaging were performed to assess the consequent disc degeneration. RESULTS: Significant disc space narrowing was observed as early as 4 wk, and osteophytes were formed at 12 wk after puncture. The magnetic resonance imaging assessment demonstrated a progressive loss of T2-weighted signal intensity at the stabbed discs throughout the 12-wk period. The histologic analysis showed a progressive loss of the normal architecture from 4 wk to the end point. The biochemical assays suggested that the expression of proteoglycan decreased progressively with increasing time. CONCLUSIONS: A simple, but minimally invasive, intervertebral disc degeneration model was established successfully using computed tomography-guided percutaneous puncture technology in the rabbit. The puncture procedure can be performed with minimal damage and handling of the other structures, ensuring a uniform reproducible disc degeneration model.

[Establishment of a rabbit model of lumbar intervertebral disc degeneration via the paraspinal approach].

OBJECTIVE: To establish a rabbit model of intervertebral disc degeneration by puncturing the anulus fibrosus through an approach between the longissimus dorsi muscle and obliquus externus abdominis. METHODS: The L(4/5) and L(5/6) intervetebral discs of 6 New Zealand white rabbits were punctured by an 18-gauge pin in the anterolateral annular fibrosus through an approach between the longissimus dorsi muscle and the obliquus externus abdominis with the right transverse processes of L(5) and L(6) resected; the L(2/3) discs were used as the control without exposure or needle stab, and the L(3/4) discs were subjected to sham operation with the discs exposed but not punctured after resecting the right transverse process of L(4). X-ray and magnetic resonance imaging (MRI) were performed preoperatively and at the 4th week after puncture. At 4 weeks after the operation, histological and immunohistochemical analyses of the discs were carried out. RESULTS: X-ray of the punctured discs at 4 weeks after the operation presented a significant decrease of disc height, osteophytosis formation, and end-plate stiffness; an obvious decrease of signal intensity on T(2)-weighted images was found in the puncture group but not in the control or sham-operated groups. Gross morphological inspection showed atrophy of the nucleus pulposus, which became loose, soft, and fragile with a light yellow color. Histological and immunohistochemical analyses showed a significant decrease of notochordal cells and type II collagen in the nucleus pulposus in the puncture group as compared to the control and sham-operated groups. CONCLUSION: Puncture through the approach between the longissimus dorsi muscle and the obliquus externus abdominis allows the establishment of a reliable animal model for studying intervertebral disc degeneration.