Implantable medical devices characterization

Li, D. Guo, G. Fan, R. Liang, J. Deng, X. Luo, F. Qian, Z. PLA/F68/Dexamethasone implants prepared by hot-melt extrusion for controlled release of anti-inflammatory drug to implantable medical devices I. Preparation, characterization and hydrolytic degradation study. Int. J. Pharm. 2013,447(1-2), 365-372. 

Bulk characterization yields information on the macroscopic properties of the biomaterial such as thermal, mechanical, solubility, optical, and dielectric properties. Surface characterization yields morphological information that is critical for interfacing the implant or drug delivery device with the host tissue. This could be achieved by microscopic and spectfoscopic methods. Next in the hierarchy is the characterization of processes such as biodegradation mechanism and kinetics under biomimetic in vitro conditions. Cases of implanted device failure need to be assessed by systematic interrogation of explanted medical devices. After knowing the basic characteristics of the biomaterial, real-time investigation of in vivo processes plays a major role in the successful journey of an implant. 

Biocompatibility as defined in Section 2.5 is a main prerequisite for the proper and safe use of medical devices consisting of a single material or material composition. In Section 4.5.1, it was demonstrated that the biophysical characterization of material surfaces only draws attention to some aspects of their response to biological systems. In order to assess biocompatibility for a device or a material, it is necessary to do a battery of tests depending on its intended use, with body contact ranging from transient skin contact to contact with blood to permanent implantation. Biocompatibihty is usually examined with three types of biological tests in vitro tests, animal experiments (in vivo tests), and clinical tests. 

Type I collagen is used in a number of medical devices including hemostats, eye shields and cosmetic implants and has extensive potential in the growth of ti.ssues in cell culture. Therefore, it is essential to understand the purification, characterization and usage of t pe I collagen. ... 

ISO/TR 37137 2014 Cardiovascular biological evaluation of medical devices—guidance for absorbable implants ASTM F215(y Standard guide for characterization and testing of biomaterial scaffolds used in tissue-engineered medical products... 

This book. Implantable Neural Prostheses 2 Techniques and Engineering Approaches, is part two of a two-volume sequence that describes state-of-the-art advances in techniques associated with implantable neural prosthetic devices. The techniques covered include biocompatibility and biostability, hermetic packaging, electrochemical techniques for neural stimulation applications, novel electrode materials and testing, thin-film flexible microelectrode arrays, in situ characterization of microelectrode arrays, chip-size thin-film device encapsulation, microchip-embedded capacitors and microelectronics for recording, stimulation, and wireless telemetry. The design process in the development of medical devices is also discussed. 

Recent studies demonstrate that cardiac resynchronization therapy (CRT) offers a promising approach to selected patients with chronic heart failure. Delayed electrical activation of the left ventricle, characterized on the ECG by a QRS duration that exceeds 120 ms, occurs in approximately one-third of patients with moderate to severe systolic heart failure. Since the left and right ventricles normally activate simultaneously, this delay results in asynchronous contraction of the left and right ventricles, which contributes to the hemodynamic abnormalities of this disorder. Implantation of a speciahzed biventricular pacemaker to restore synchronous activation of the ventricles can improve ventricular contraction and hemodynamics. Recent trials show improvements in exercise capacity, NYHA classification, quality of life, hemodynamic function, and hospitalizations. A device that combined CRT with an implantable cardioverter-defibrillator (ICD) improved survival in addition to functional status. CRT is currently indicated only in NYHA class ni-IV patients receiving optimal medical therapy (ACE inhibitors, diuretics, -blockers, and digoxin) and... 

Since USM mills can be used on these multipurpose milling machines, the micro milling process is considered a flexible manufacturing process. In addition, the process is characterized by low setup costs, unlimited part materials, and a high material removal rate (Ozel et al. 2011). It is, for example, used to machine small features in molds used for mass production (e.g., microfluidic devices), to structure medical implants for better biocompatibility, to generate deep x-ray lithography masks, and to manufacture prototypes rapidly as well as efficiently (Aurich et al. 2012). 

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