Target Vertebrae Research Articles

Morphometric analysis using multiplanar reconstructed CT of the lumbar pedicle in patients with degenerative lumbar scoliosis characterized by a Cobb angle of 30° or greater

Although the anatomy of the thoracic pedicle in adolescent idiopathic scoliosis is well known, that of the lumbar pedicle in degenerative lumbar scoliosis is not. The morphometric differences between the pedicles on the concave and convex sides can result in an increased risk of malpositioned pedicle screws. The purpose of this study was to analyze the lumbar pedicle morphology in degenerative lumbar scoliosis using multiplanar reconstructed CT. The study group comprised 16 consecutive patients (1 man and 15 women, mean age 70.9 ± 4.5 years) with degenerative lumbar scoliosis characterized by a Cobb angle of at least 30° who underwent preoperative helical CT scans. The CT data in DICOM format were reconstructed, and the following parameters were measured for each pedicle inside the curves: the inner cortical transverse pedicle width (TPWi) and outer cortical transverse pedicle width (TPWo) and axial angle, all on an axial plane, and the inner cortical minimum pedicle diameter (MPDi) and outer cortical minimum pedicle diameter (MPDo) and cephalocaudal inclination of the pedicle, all on the plane perpendicular to the pedicle axis. The cortical thickness and cortical ratio of the pedicles on the axial plane and the plane perpendicular to the pedicle axis were calculated. Data were obtained for a total of 124 pedicles; L-1, 26 pedicles in 13 patients; L-2, 32 pedicles in 16 patients; L-3, 32 pedicles in 16 patients; L-4, 28 pedicles in 14 patients; and L-5, 6 pedicles in 3 patients. Among the target vertebrae, the TPWi, MPDi, and MPDo were significantly smaller and the axial angle was significantly larger on the concave side than on the convex side (TPWi, 6.37 vs 6.70 mm, p < 0.01; MPDi, 5.15 vs 5.67 mm, p < 0.01; MPDo, 7.91 vs 8.37 mm, p < 0.05; axial angle, 11.79° vs 10.56°, p < 0.01). The cortical ratio of the pedicles was larger on the concave side than on the convex side (on the axial plane, 0.29 vs 0.26, p < 0.05; on the plane perpendicular to the pedicle axis, 0.36 vs 0.32, p < 0.01). These differences were most evident at L-4. This study demonstrated lumbar pedicle asymmetry in degenerative lumbar scoliosis. The authors speculate that these asymmetrical changes were attributed to the remodeling caused by axial load imbalance and the limited space available for pedicles on the concave side. On the concave side, because of the narrower pedicle diameter and larger axial angle, surgeons should carefully determine screw size and direction when inserting pedicle screws to prevent possible pedicle wall breakage and neural damage.

Incidental finding of hiatal hernia on 99mTc-Sestamibi whole-body scan in thyroid cancer evaluation

We investigated the safety and feasibility of the combination of samarium-153-ethylenediamine tetramethylene phosphonate (153Sm-EDTMP)-incorporated bone cement (BC) with percutaneous vertebroplasty (PVP) in dogs.153Sm-EDTMP-incorporated BC was prepared by combining solid 153Sm-EDTMP and polymethylmethacrylate (PMMA) immediately before PVP. It was then injected into the vertebrae of four healthy mongrel dogs (two males and two females) by PVP under CT guidance. Each dog was subjected to five PVP sessions at a 153Sm-EDTMP dose of 30–70 mCi. The suppressive effect of local injection of 153Sm-EDTMP on the hematopoietic system was evaluated through counting of peripheral blood cells. Distribution of 153Sm-EDTMP-incorporated BC and the status of tissues adjacent to injected vertebrae were evaluated with SPECT, CT and MRI. Histopathology was carried out to assess the influence of PVP on the vertebra and adjacent tissues at the microscopic level.PVP was done successfully, and all dogs exhibited normal behavior and stable physical signs after procedures. 153Sm-EDTMP-incorporated BC was concentrated mainly in target vertebrae, and the peripheral blood cells remained within normal range. The spinal cord and tissues around BC did not exhibit signs of injury even when the dosage of 153Sm-EDTMP increased from 30 mCi to 70 mCi.A dose lower than 70 mCi of 153Sm is safe when it was injected into vertebrae. 153Sm-EDTMP-incorporated BC did not influence the effect of PVP. This means might strengthen anti-tumor activity locally for vertebra with osseous metastasis without damaging adjacent tissues.

Safety and feasibility of percutaneous vertebroplasty with radioactive 153Sm PMMA in an animal model

Purpose We investigated the safety and feasibility of the combination of samarium-153-ethylenediamine tetramethylene phosphonate ( 153Sm-EDTMP)-incorporated bone cement (BC) with percutaneous vertebroplasty (PVP) in dogs. Methods and materials 153Sm-EDTMP-incorporated BC was prepared by combining solid 153Sm-EDTMP and polymethylmethacrylate (PMMA) immediately before PVP. It was then injected into the vertebrae of four healthy mongrel dogs (two males and two females) by PVP under CT guidance. Each dog was subjected to five PVP sessions at a 153Sm-EDTMP dose of 30–70 mCi. The suppressive effect of local injection of 153Sm-EDTMP on the hematopoietic system was evaluated through counting of peripheral blood cells. Distribution of 153Sm-EDTMP-incorporated BC and the status of tissues adjacent to injected vertebrae were evaluated with SPECT, CT and MRI. Histopathology was carried out to assess the influence of PVP on the vertebra and adjacent tissues at the microscopic level. Results PVP was done successfully, and all dogs exhibited normal behavior and stable physical signs after procedures. 153Sm-EDTMP-incorporated BC was concentrated mainly in target vertebrae, and the peripheral blood cells remained within normal range. The spinal cord and tissues around BC did not exhibit signs of injury even when the dosage of 153Sm-EDTMP increased from 30 mCi to 70 mCi. Conclusion A dose lower than 70 mCi of 153Sm is safe when it was injected into vertebrae. 153Sm-EDTMP-incorporated BC did not influence the effect of PVP. This means might strengthen anti-tumor activity locally for vertebra with osseous metastasis without damaging adjacent tissues.