Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed,...Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed, developed and made applicable. This paper introduces a three dimensional opt ical measurement method based on digital fringe projection technique in RE to im prove the technique through its application. A practical example is presented an d the result demonstrates the applicability and feasibility of the measurement s ystem as well as the reliability and validity of relevant methods and algorithms .展开更多
Objective To reconstruct the human optic canal and its inner structures, and to provide detailed knowledge of this region for optic nerve decompression for further understanding on the pathologic mechanisms of indire...Objective To reconstruct the human optic canal and its inner structures, and to provide detailed knowledge of this region for optic nerve decompression for further understanding on the pathologic mechanisms of indirect optic nerve injury Methods Six optic canals and their inner structures were reconstructed using a computer aided 3 dimensional reconstruction system Quantitative measurement of the canal wall thickness, bony canal transverse area, optic nerve transverse area, dural sheath transverse area, subarachnoid space transverse area, and subarachnoid space volume were done by means of the computer morphometric analysis system The detailed spatial relationship among intracanalicular structures were also carefully identified on the 3 D models Results The thinnest portion of the canal was the middle part of the medial wall (0 45±0 35?mm) and the narrowest space was in the middle part of the optic canal (the transverse area was 18 21±2 50?mm 2) The volume of subarachnoid space which can be considered the compensatory space for distention incurred by the hemorrhage, optic nerve edema, or hematoma was 21 16±4 31?mm 3 At the cranial opening ,the middle part and orbital opening, its transverse area was 4 45±1 12?mm 2, 2 68±1 32?mm 2 and 1 23±0 83?mm 2, respectively Conclusions Since the compensatory space was limited, even a tiny amount of blood or swelling of the nerve may cause optic nerve compression Because the narrowest space was in the middle part of the optic canal and the compensatory space for distention gradually decreases from cranial end to orbital end, the middle part and the anterior part of the optic canal and dural sheath are critical in optic nerve decompression展开更多
基金Project supported by the Science Foundation of Shanghai Munici pal Commission of Science and Technology ( Grant No.011461059)
文摘Acquisition of physical data with high precision is a key step in reverse engineering (RE). It is an important stimulative for the progress of reverse engineering with which various digitizing devices are invent ed, developed and made applicable. This paper introduces a three dimensional opt ical measurement method based on digital fringe projection technique in RE to im prove the technique through its application. A practical example is presented an d the result demonstrates the applicability and feasibility of the measurement s ystem as well as the reliability and validity of relevant methods and algorithms .
基金ThisresearchwassupportedbyMilitaryMedicalandHygienic"95Project"ResearchGrantPLA China (No 96Z0 5 7)
文摘Objective To reconstruct the human optic canal and its inner structures, and to provide detailed knowledge of this region for optic nerve decompression for further understanding on the pathologic mechanisms of indirect optic nerve injury Methods Six optic canals and their inner structures were reconstructed using a computer aided 3 dimensional reconstruction system Quantitative measurement of the canal wall thickness, bony canal transverse area, optic nerve transverse area, dural sheath transverse area, subarachnoid space transverse area, and subarachnoid space volume were done by means of the computer morphometric analysis system The detailed spatial relationship among intracanalicular structures were also carefully identified on the 3 D models Results The thinnest portion of the canal was the middle part of the medial wall (0 45±0 35?mm) and the narrowest space was in the middle part of the optic canal (the transverse area was 18 21±2 50?mm 2) The volume of subarachnoid space which can be considered the compensatory space for distention incurred by the hemorrhage, optic nerve edema, or hematoma was 21 16±4 31?mm 3 At the cranial opening ,the middle part and orbital opening, its transverse area was 4 45±1 12?mm 2, 2 68±1 32?mm 2 and 1 23±0 83?mm 2, respectively Conclusions Since the compensatory space was limited, even a tiny amount of blood or swelling of the nerve may cause optic nerve compression Because the narrowest space was in the middle part of the optic canal and the compensatory space for distention gradually decreases from cranial end to orbital end, the middle part and the anterior part of the optic canal and dural sheath are critical in optic nerve decompression
