Showing 2 results for Dimension
Lotfinia I, Ghavami M, Haddadi K, Vahedi P,
Volume 68, Issue 2 (5-2010)
Abstract
Background: Pedicular screws are currently the gold standard of internal fixation of spinal column. Pedicular screws have their own complications, however the surgeon should be aware of morphometery of pedicles, as well as the anatomy of surrounding neural structures to minimize these risks. No national study has ever examined the physical characteristics of lumbar pedicles and this study is unique for this purpose.Methods: This study covers the patients undergoing lumbar spinal CT-scanning due to variable causes. 25 vertebrae were selected in either gender, 18 years or older and EFilm computer software was employed to measure different diameters of pedicle and the results were analyzed with p≤0.05 regarded as significant.Results: L5 pedicle was the widest (16.8 mm), while L1 was the narrowest (8.25 mm).this figure was 8.82, 10.48 and 12.86 mm for L2, L3, L4 respectively. Longitudinal depth of pedicle was 47.98, 48.68, 50.42, 48.32 and 47.8 mm for L1, L2, L3, L4, L5 respectively.Statistically significant differences were found between some dimensions detected in our study and similar studies.
Conclusions: The advantages of pedicular screws and rods to stabilize spinal column are well known. To avoid neurological complications, an understanding of anatomy and pedicle orientation is mandatory. The shape and diameters of pedicles are different base on races. Some differences were found in our study regarding pedicle dimensions.
Mahdi Aghili , Maryam Moshtaghi , Farhad Samiee , Ebrahim Esmati , Mahbod Esfahani , Hasan Ali Nedaee , Peiman Haddad ,
Volume 68, Issue 8 (11-2010)
Abstract
Background: The current standard of adjuvant management for gastric cancer after curative resection based on the results of intergroup 0116 is concurrent chemoradiation. Current guidelines for designing these challenging fields still include two-dimensional simulation with simple AP-PA parallel opposed design. However, the implementation of radiotherapy (RT) remains a concern. Our objective was to compare three-dimensional (3D) techniques to the more commonly used AP-PA technique.
Methods: A total of 24 patients with stages II-IV adenocarcinoma of the stomach were treated with adjuvant postoperative chemoradiation with simple AP-PA technique, using Cobalt-60. Total radiation dose was 50.4Gy. Landmark-based fields were simulated to assess PTV coverage. For each patient, three additional radiotherapy treatment plans were generated using three-dimensional (3D) technique. The four treatment plans were then compared for target volume coverage and dose to normal tissues (liver, spinal cord, kidneys) using dose volume histogram (DVH) analysis.
Results: The three-dimensional planning techniques provided 10% superior PTV coverage compared to conventional AP-PA fields (p<0.001). Comparative DVHs for the right kidney, left kidney and spinal cord demonstrate lower radiation doses using the 3D planning techniques (p<0.0001), the liver dose is higher (p=0.03), but is still well below liver tolerance.
Conclusion: Despite the department protocol using conventional planning, 3D radiotherapy provides 10% superior PTV coverage. It is associated with reduced radiation doses to the kidneys and spinal cord compared to AP-PA techniques with the potential to reduce treatment toxicity.