ABSTRACT
BACKGROUND: Implantation of biodegradable bone scaffold is regarded as a promising way to repair bone defects, and the coupling process of scaffold degradation and bone formation is influenced by the physical-exercise-induced mechanical stimulus. METHODS: The scaffold degradation was modeled by a mechanical-stress-regulated degradation algorithm, and the bone formation was modeled by a strain-energy-density-based formation algorithm. Then, the two models were coupled together by considering the transformation of three material states. Employing the finite element method, the effect of the mechanical stimulus represented by exercise duration (ED) and exercise intensity (EI) on the coupling scaffold degradation and bone formation was numerically studied. RESULTS: Both the final and minimum bone volume fraction and Young's modulus of the coupling scaffold-bone system were generally increased with improved EDs and EIs. The bone volume fractions of the formed bone in all cases were comparable to selected natural cancellous bones, but the Young's moduli were greater than the natural cancellous bones. CONCLUSIONS: This work sheds light on the regulation of mechanical stimulus on the coupling process of the scaffold degradation and bone formation, and provides a potential in silico way to pre-evaluate the performance of degradable scaffold for bone repair.
Subject(s)
Bone and Bones , Osteogenesis , Biomechanical Phenomena , Computer Simulation , Elastic Modulus , Stress, MechanicalABSTRACT
Objective:The aim of this study is to investigate the application of 3D simulation temporal-bone-system for temporal bone anatomy training.Method:3D simulation temporal-bone-system in the anatomy workshop was introduced in Beijing Children's Hospital from 2014 to 2015.Each participant was trained by cadaver dissection and 3D simulation temporal-bone-anatomy,and they also completed the questionnaires and evaluated the procedure.Then the difference was analyzed.Result:â In stage of mastoid outline,the damage of structure in 3D systemis higher than that in cadaver dissection(33.3%>22.2%),but there were no significant difference between them in the proportion of exposure.On the opening of attic,facial recess,facial nerve,the damage and the proportion of the non-exposed of cadaver dissection is higher.â¡There were no significant difference between them in the anatomical structures,levels of pollution,taste,cost and reproducibility(P>0.05),but in the aspect of time,relevance of CT with temporal bone,the similarity,and the force feedback,they had significant differences(P<0.01).Conclusion:3D simulation temporal-bone-system had better training effect in specialized otolaryngologist.It not only to help clinicians better understanding the temporal bone and surrounding structures,but also to emphasize the knowledge of the anatomy in temporal bone.
ABSTRACT
La medicina nuclear es la especialidad médica que se ocupa del diagnóstico, tratamiento e investigación médica mediante el uso de radioisótopos como fuentes abiertas. A menudo, las personas presentan diferentes condiciones patológicas óseas como la osteoporosis, el cáncer de hueso primario, las metástasis óseas, la artrosis y la artritis. Como objetivo de esta revisión se presentaron estadísticas internacionales y nacionales, y se evaluó la incidencia de esas afecciones. Además, se identificaron los radiofármacos más empleados en la actualidad para el diagnóstico y tratamiento de las enfermedades óseas, así como el uso combinado con las técnicas de imagen más utilizadas mediante la revisión de diferentes estudios clínicos. Se expuso la utilidad de la gammagrafía ósea para el diagnóstico y la confirmación de las afecciones estudiadas. Igualmente, se presentó el empleo de nuevas técnicas como las tomografías por emisión de fotón único o por emisión de positrones. Se observó que el radioisótopo más empleado para el diagnóstico de enfermedades del sistema óseo es el 99mTc por sus características físicas y químicas, mientras que para terapia se emplean 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, 117mSn, según el tipo, ubicación y magnitud de las lesiones y la disponibilidad del radioisótopo. En la actualidad, el desarrollo de los radiofármacos se ha centrado en la combinación de estos radioisótopos con diferentes biomoléculas para mejorar sus propiedades y ampliar su campo de aplicaciones(AU)
Nuclear medicine is the medical specialty that deals with clinical diagnosis, treatment and research through the use of isotopes as open sources. Bone diseases such as osteoporosis, primary bone cancer, bone metastases, arthrosis and arthritis are common among the population. The objective of this review was to present international and national statistics, and evaluate the incidence of these disorders. Additionally, a review was conducted of various clinical studies to identify the radiopharmaceuticals most frequently used to diagnose and treat bone disease, and their combination with the most common imaging techniques. A presentation was made of the usefulness of bone gammagraphy and the confirmation of the disorders studied. Reference was also made to the use of new techniques such as single photon emission tomography or positron emission tomography. It was found that the radioisotope most commonly used to diagnose diseases of the bone system was 99mTc, due to its physical and chemical characteristics, whereas 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, 117mSn are used for therapeutic purposes, depending on the type, location and magnitude of the lesions and the availability of the radioisotope. At present, radiopharmaceutical development centers on combining these radioisotopes with various biomolecules to improve their properties and broaden their field of application(A)
La médecine nucléaire est la spécialité médicale s'occupant du diagnostic, du traitement et de la recherche médicale au moyen de radioisotopes comme sources ouvertes. Les personnes sont souvent touchées par différentes conditions pathologiques osseuses telles que l'ostéoporose, le cancer d'os primaire, les métastases osseuses, l'arthrose, et l'arthrite. Le but de cette révision est de présenter des statistiques internationales et nationales, et d'évaluer l'incidence de ces affections. Grâce à la révision de différentes études cliniques, on a également identifié les traceurs isotopiques les plus souvent utilisés de nos jours pour le diagnostic et le traitement des maladies osseuses, ainsi que l'emploi combiné des techniques par image les plus fréquentes. L'utilité de la gammagraphie osseuse pour le diagnostic et la confirmation des affections étudiées a été mise en évidence. De nouvelles technologies telles que les tomographies par émission de photon unique ou par émission de positons a été également présentées. On a trouvé que le radioisotope le plus souvent utilisé pour le diagnostic des maladies du système osseux est le 99mTc, dû à ses caractéristiques physiques et chimiques, tandis que pour la thérapie, les 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, et 117mSn sont utilisés selon le type, la localisation et la magnitude des lésions, et la disponibilité du radioisotope. Aujourd'hui, le développement des traceurs isotopiques est axé sur la combinaison de ces radioisotopes avec différentes biomolécules pour améliorer leurs propriétés et élargir leur champ d'applications(AU)
Subject(s)
Humans , Diagnostic Techniques, Radioisotope/instrumentation , Disease , Radiopharmaceuticals/therapeutic use , Musculoskeletal System/diagnostic imaging , Nuclear Medicine/methods , Osteoarthritis/etiology , Osteoporosis/epidemiology , Arthritis/etiology , Neoplasm MetastasisABSTRACT
La medicina nuclear es la especialidad médica que se ocupa del diagnóstico, tratamiento e investigación médica mediante el uso de radioisótopos como fuentes abiertas. A menudo, las personas presentan diferentes condiciones patológicas óseas como la osteoporosis, el cáncer de hueso primario, las metástasis óseas, la artrosis y la artritis. Como objetivo de esta revisión se presentaron estadísticas internacionales y nacionales, y se evaluó la incidencia de esas afecciones. Además, se identificaron los radiofármacos más empleados en la actualidad para el diagnóstico y tratamiento de las enfermedades óseas, así como el uso combinado con las técnicas de imagen más utilizadas mediante la revisión de diferentes estudios clínicos. Se expuso la utilidad de la gammagrafía ósea para el diagnóstico y la confirmación de las afecciones estudiadas. Igualmente, se presentó el empleo de nuevas técnicas como las tomografías por emisión de fotón único o por emisión de positrones. Se observó que el radioisótopo más empleado para el diagnóstico de enfermedades del sistema óseo es el 99mTc por sus características físicas y químicas, mientras que para terapia se emplean 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, 117mSn, según el tipo, ubicación y magnitud de las lesiones y la disponibilidad del radioisótopo. En la actualidad, el desarrollo de los radiofármacos se ha centrado en la combinación de estos radioisótopos con diferentes biomoléculas para mejorar sus propiedades y ampliar su campo de aplicaciones(AU)
Nuclear medicine is the medical specialty that deals with clinical diagnosis, treatment and research through the use of isotopes as open sources. Bone diseases such as osteoporosis, primary bone cancer, bone metastases, arthrosis and arthritis are common among the population. The objective of this review was to present international and national statistics, and evaluate the incidence of these disorders. Additionally, a review was conducted of various clinical studies to identify the radiopharmaceuticals most frequently used to diagnose and treat bone disease, and their combination with the most common imaging techniques. A presentation was made of the usefulness of bone gammagraphy and the confirmation of the disorders studied. Reference was also made to the use of new techniques such as single photon emission tomography or positron emission tomography. It was found that the radioisotope most commonly used to diagnose diseases of the bone system was 99mTc, due to its physical and chemical characteristics, whereas 186Re, 188Re, 153Sm, 177Lu, 32P, 89Sr, 85Sr, 117mSn are used for therapeutic purposes, depending on the type, location and magnitude of the lesions and the availability of the radioisotope. At present, radiopharmaceutical development centers on combining these radioisotopes with various biomolecules to improve their properties and broaden their field of application(AU)
