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Surgical Implantation (surgical + implantation)
Selected AbstractsPercutaneous stent-mounted valve for treatment of aortic or pulmonary valve diseaseCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 1 2004John G. Webb MD Abstract The objective of this study was to develop a prosthetic cardiac valve designed for percutaneous transcatheter implantation. Percutaneous catheter-based therapies play a limited role in the management of cardiac valve disease. Surgical implantation of prosthetic valves usually requires thoracotomy and cardiopulmonary bypass. The stent-valve is constructed of a rolled sheet of heat-treated nitinol. Although malleable when cooled, once released from a restraining sheath at body temperature the stent unrolls, becomes rigid, and assumes its predetermined cylindrical conformation. A ratcheting lock-out mechanism prevents recoil and external protrusions facilitate anchoring. Valve leaflets are constructed of bovine pericardium. The feasibility of catheter implantation, prosthetic valve function, and survival were investigated in an animal model. In vitro and pulse duplicator testing documented valve durability. Endovascular delivery of the prototype stent-valve to the aortic or pulmonary position was feasible. Accurate positioning was required to ensure exclusion of the native valve leaflets and, in the case of the aortic valve, to avoid compromise of the coronary ostia or mitral apparatus. Oversizing of the stent in relation to the valve annulus was desirable to facilitate anchoring and prevent paravalvular insufficiency. Stent-valve implantation proved feasible and compatible with survival in an animal model. Transcatheter implantation of prosthetic valves is possible. Further evolution of this technology will involve lower-profile devices with design features that facilitate vascular delivery, visualization, positioning, deployment, and valvular function. Catheter Cardiovasc Interv 2004;63:89,93. © 2004 Wiley-Liss, Inc. [source] rhBMP-2/,BSM® Induces Significant Vertical Alveolar Ridge Augmentation and Dental Implant OsseointegrationCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2002Ulf M.E. Wikesjö DDS ABSTRACT Background: Recombinant human bone morphogenetic protein 2 (rhBMP-2) in a carrier has been shown to induce significant bone formation. Several candidate carriers, however, lack structural integrity to offset compressive forces that may compromise rhBMP-2 bone induction, in particular, for challenging onlay indications such as alveolar ridge augmentation. Purpose: The objective of this study was to evaluate rhBMP-2 in a calcium-phosphate cement carrier, ,BSM, for vertical alveolar ridge augmentation and immediate dental implant Osseointegration. Materials and Methods: Six adult Hound Labrador mongrels with 5 mm critical size supra-alveolar peri-implant defects were used. Three animals received rhBMP-2/,BSM (rhBMP-2 at 0.40 and 0.75 mg/mL) in contralateral jaw quadrants (total implant volume/defect , 1.5 mL). Three animals received ,BSM without rhBMP-2 (control group). The animals were euthanized at 16 weeks post surgery, and block biopsies were processed for histologie and histometric analysis. Results: rhBMP-2/,BSM induced substantial augmentation of the alveolar ridge. Control sites exhibited limited new bone formation. Vertical bone augmentation averaged (SD) 4.9 ± 1.0 mm (rhBMP-2 at 0.40 mg/mL), 5.3 ± 0.3 mm (rhBMP-2 at 0.75 mg/mL), and 0.4 ± 0.4 mm (control); new bone area 8.5 ± 4.2 mm 2, 9.0 ± 1.9 mm 2, and 0.5 ± 0.4 mm 2; new bone density 55.1 ± 6.4%, 61.1 ± 6.0%, and 67.7 ± 9.5%; and new bone-implant contact 26.9 ± 17.5%, 28.5 ± 1.4%, and 24.6 ± 16.1%, respectively. Residual ,BSM comprised 1% of the new bone. Bone density for the contiguous resident bone ranged from 65 to 71%, and bone-implant contact ranged from 49 to 64%. Conclusions: Surgical implantation of rhBMP-2/,BSM appears an effective protocol for vertical alveolar ridge augmentation procedures and immediate dental implant Osseointegration and for onlay indications of lesser complexity. [source] Elution kinetics, antimicrobial efficacy, and degradation and microvasculature of a new gentamicin-loaded collagen fleeceJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2009Olaf Kilian Abstract Management of bone and soft tissue infections generally includes surgical procedures as well as attendant treatment and prevention with gentamicin-loaded fleeces. Conventional gentamicin-containing collagen fleeces currently in use are strongly acidic and exhibit limited biocompatibility thereby adversely affecting wound healing. To improve the antibiotic delivery system, a new phosphate-buffered, gentamicin-loaded fleece with pH,neutral properties has been developed (Jason G®). This study aimed at comparing the elution kinetics of gentamicin release and the antimicrobial efficacy of conventional fleeces with the newly developed fleece in vitro. In addition, degradation and microvasculature of implanted fleeces were examined in a rat model and assessed using histology, as well as detection of ED-1 and PECAM-expression using immunohistochemistry. We show that the phosphate-buffered fleeces have reduced release (p < 0.05) of the integrated gentamicin. However, all of the fleeces tested had a significant antimicrobial effect on the growth of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa strains (p < 0.01). Among the fleeces tested, the new Jason G® fleece had the weakest but nevertheless sufficient antimicrobial effectiveness. Evaluation of the antibiotic effect in the prevention of an infection showed no differences between the applied fleeces. Following surgical implantation of fleece in the backs of Wistar rats we observed, on day 5 after implantation, an increase in cell infiltration and microvascularization with the phosphate-buffered fleece as compared with conventional fleeces, which show necrotic cells on their surface. Unlike the acidic fleeces, on day 15 after implantation the pH,neutral fleece was resorbed widely. Here, we show that the new, pH,neutral, gentamicin-containing fleece Jason G® exhibits good overall antimicrobial effectiveness against both gram-positive and gram-negative bacteria in vitro with improved degradation properties and microvasculature formation in vivo. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [source] Monitoring surgical performance: an application to total hip replacementJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 3 2009David J. Biau MD Abstract Rationale, aims and objectives, Inadequate surgical implantation of a hip replacement may result in decreased patient satisfaction and reduced implant survival. The objective was to monitor surgical performance in hip replacement. Method, The study took place at a teaching centre. All primary total hip replacements were prospectively included in the series. For each hip replacement, intraoperative technical errors, cup and stem fixation and position, and postoperative complications were recorded. If all items rated were correct, the procedure was considered as correct. The Cumulative Sums (CUSUM) test was used to monitor the performance of the centre. A 90% proportion of successful procedures was considered as adequate performance and a 75% proportion of successful procedures was deemed as inadequate performance. Meetings were conducted to discuss the results of monitoring. Results, Eighty-three total hip replacements were monitored. Overall, 28 procedures (34%) were considered inadequate. The most potent reasons for inadequate performance were cup positioning and stem fixation. The CUSUM test signalled after the second procedure that performance was inadequate. After the first meeting, despite an improvement was seen, the CUSUM test raised an alarm indicating inadequate performance. The study was stopped after the second meeting because of funding reasons before it could be demonstrated that performance had reached the desired level. Conclusion, This study has demonstrated that implementing a dedicated system to monitor surgical performance in a teaching hospital improves the quality of implantation of total hip replacements. Nonetheless, the target of ninety percent of adequate primary total hip replacement could not be reached and efforts should be continued. [source] Improvement in a quantitative measure of bradykinesia after microelectrode recording in patients with Parkinson's disease during deep brain stimulation surgeryMOVEMENT DISORDERS, Issue 5 2006Mandy Miller Koop MS Abstract It is widely accepted that patients with Parkinson's disease experience immediate but temporary improvement in motor signs after surgical implantation of subthalamic nucleus (STN) deep brain stimulating electrodes before the electrodes are activated, although this has never been formally studied. Based on anecdotal observations that limb mobility improved just after microelectrode recording (MER) during deep brain stimulation (DBS) procedures, we designed a prospective study to measure upper extremity bradykinesia using a quantitative measure of angular velocity. Measurements were made pre- and post-MER and during intraoperative DBS. Analysis of 98 STN DBS procedures performed on 61 patients showed that MER did not create adverse clinical symptoms despite concerns that MER increases morbidity. Quantitative upper extremity bradykinesia improved after MER alone, and further improvement was seen during intraoperative DBS. Electrophysiological data from each case were then compared to the improvement in bradykinesia post-MER alone and a significant correlation was found between the improvement in arm bradykinesia, the number of passes through the STN with somatosensory driving, and also with the number of arm cells with somatosensory driving in the STN, but not with total number of passes, total number of passes through the STN, or total number of cells with somatosensory driving in the STN. This study demonstrates that there is a significant improvement in upper extremity bradykinesia just after MER, before inserting or activating the DBS electrode in patients with Parkinson's disease who undergo STN DBS. © 2006 Movement Disorder Society [source] Telemetric Intracavernosal and Intraspongiosal Pressure MonitoringTHE JOURNAL OF SEXUAL MEDICINE, Issue 10 2008Rany Shamloul MD ABSTRACT Introduction., Despite the major breakthroughs basic research in erectile physiology experienced in the last, most of the methods used for quantitative assessment of erectile function in longitudinal studies suffer many drawbacks. Objective., This review will focus on radiotelemetric assessment of intracavernosal (ICP) and intraspongiosal (ISP) regarding the technique, data collection, interpretation, and overall benefits. Results., Telemetric recording of ICP and ISP allows for qualitative and quantitative assessment of erectile responses in experimental animals, a characteristic that is not possible using other techniques. This technique has many advantages that can collectively lead to production of high quality data regarding erection. The system suffers two drawbacks, its high cost and the need for surgical implantation of the transmitter. Conclusion., The use of telemetric monitoring of ICP and ISP carries many advantages that will, hopefully, establish this technique as the gold standard method for assessment of erectile responses in the near future. Shamloul R. Telemetric intracavernosal and intraspongiosal pressure monitoring. J Sex Med 2008;5:2246,2252. [source] | ||||||||||