Development and evaluation of the manufacture of a coronary stent for the South African market

dc.contributor.authorLehmann, Markusen_ZA
dc.date.accessioned2017-12-08T13:56:41Z
dc.date.available2017-12-08T13:56:41Z
dc.date.issued2000en_ZA
dc.description.abstractThe need for economic treatment of coronary heart disease in South Africa and the popularity of coronary stent implantation as an effective treatment increases. Stent implants have had to be imported to date with significant cost involved. The project in hand therefore deals with the evaluation of the possibilities of economical local manufacture of a coronary stent. The design of several coronary stents currently in use was carefully analysed and the results of clinical application described in the literature were reviewed. After evaluating the patent situation, a suitable design concept was chosen, based primarily on the availability of manufacturing equipment. The design concept of choice is the balloon expandable slotted tube variety. Stents of this most popular slotted tube design are usually laser cut out of a tube with good results. Since there was no suitable laser cutting equipment in use in South Africa, it was undertaken to manufacture stent prototypes by spark erosion to establish the general suitability of the method for stent manufacturing. The initial design was adjusted several times to the manufacturing process and suitable machine parameters were evaluated. For comparison a stent of a similar design was laser cut by an established European manufacturer. The geometry of the most favourable prototypes was analysed by computer simulation using finite element analysis, followed by simple physical tests of deployment and radial strength. The quality of manufacturing was evaluated with electron microscopy. The computational and mechanical test results of the design analysis yielded largely satisfactory results, but it was found that the manufacturing process of spark erosion is not suitable to manufacture products that would have to compete on the current sophisticated market. With the spark erosion equipment, neither a satisfying surface quality nor acceptable geometrical tolerances could be achieved. This was particularly obvious after comparison with the laser cut stent sample of the same design. An improvement in quality of the spark erosion process would require extensive fine-tuning and would increase the already very long manufacturing time and the cost significantly. Subcontracted laser cutting in Europe was found to be more reliable and economical.en_ZA
dc.identifier.apacitationLehmann, M. (2000). <i>Development and evaluation of the manufacture of a coronary stent for the South African market</i>. (Thesis). University of Cape Town ,Faculty of Health Sciences ,Division of Biomedical Engineering. Retrieved from http://hdl.handle.net/11427/26517en_ZA
dc.identifier.chicagocitationLehmann, Markus. <i>"Development and evaluation of the manufacture of a coronary stent for the South African market."</i> Thesis., University of Cape Town ,Faculty of Health Sciences ,Division of Biomedical Engineering, 2000. http://hdl.handle.net/11427/26517en_ZA
dc.identifier.citationLehmann, M. 2000. Development and evaluation of the manufacture of a coronary stent for the South African market. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Lehmann, Markus AB - The need for economic treatment of coronary heart disease in South Africa and the popularity of coronary stent implantation as an effective treatment increases. Stent implants have had to be imported to date with significant cost involved. The project in hand therefore deals with the evaluation of the possibilities of economical local manufacture of a coronary stent. The design of several coronary stents currently in use was carefully analysed and the results of clinical application described in the literature were reviewed. After evaluating the patent situation, a suitable design concept was chosen, based primarily on the availability of manufacturing equipment. The design concept of choice is the balloon expandable slotted tube variety. Stents of this most popular slotted tube design are usually laser cut out of a tube with good results. Since there was no suitable laser cutting equipment in use in South Africa, it was undertaken to manufacture stent prototypes by spark erosion to establish the general suitability of the method for stent manufacturing. The initial design was adjusted several times to the manufacturing process and suitable machine parameters were evaluated. For comparison a stent of a similar design was laser cut by an established European manufacturer. The geometry of the most favourable prototypes was analysed by computer simulation using finite element analysis, followed by simple physical tests of deployment and radial strength. The quality of manufacturing was evaluated with electron microscopy. The computational and mechanical test results of the design analysis yielded largely satisfactory results, but it was found that the manufacturing process of spark erosion is not suitable to manufacture products that would have to compete on the current sophisticated market. With the spark erosion equipment, neither a satisfying surface quality nor acceptable geometrical tolerances could be achieved. This was particularly obvious after comparison with the laser cut stent sample of the same design. An improvement in quality of the spark erosion process would require extensive fine-tuning and would increase the already very long manufacturing time and the cost significantly. Subcontracted laser cutting in Europe was found to be more reliable and economical. DA - 2000 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2000 T1 - Development and evaluation of the manufacture of a coronary stent for the South African market TI - Development and evaluation of the manufacture of a coronary stent for the South African market UR - http://hdl.handle.net/11427/26517 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/26517
dc.identifier.vancouvercitationLehmann M. Development and evaluation of the manufacture of a coronary stent for the South African market. [Thesis]. University of Cape Town ,Faculty of Health Sciences ,Division of Biomedical Engineering, 2000 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/26517en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDivision of Biomedical Engineeringen_ZA
dc.publisher.facultyFaculty of Health Sciencesen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherBiomedical Engineeringen_ZA
dc.titleDevelopment and evaluation of the manufacture of a coronary stent for the South African marketen_ZA
dc.typeMaster Thesis
dc.type.qualificationlevelMasters
dc.type.qualificationnameMSc (Med)en_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
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