domingo, 14 de febrero de 2010

The Role of Engineering Principles in the Medical Utilization of Electromagnetic Energies from kHz to Visible Light



The Role of Engineering Principles in the Medical
Utilization of Electromagnetic Energies from kHz
to Visible Light


The use of RF/microwaves in medicine has increased dramatically over the last 
ten years. RF and microwave therapies for the treatment of cancer in humans are well 
documented, and are presently used in many cancer centers.



RF treatment for supra 
ventricular arrhythmias, and more recently for the treatment of ventricular tachycardia, are 
currently employed by major hospitals. RF/microwave are also used in human subjects 
for the treatment of benign prostatic hyperplasia (BPH). In the last few years, several 
otolaryngological centers have been utilizing RF to treat upper airway obstruction and to 
alleviate sleep apnea.













Many centers also utilize RF for the treatment of gastro-esophageal 
disease (GERD), for pain management, and for endometrial ablation. Balloon microwave
catheters for ablating solid tumors, then forming cavities in those tumors for the local 
delivery of therapeutic agents, are currently being investigated.



















New modalities are being 
studied, such as RF/microwave for the enhancement of drug absorption and microwave 
septic wound treatment, microwave imaging for the detection of breast cancer, epidemiological 
studies on the effects of rats' exposure to microwave, as well as tissue regeneration using 
electromagnetic fields. In addition, technology is presently being developed that allows for
permanent implantation of microwave wireless sensors in humans. A permanently implantable 
intra-cranial pressure monitor is one such application of the latter technology. Many more areas 
of research are currently being investigated, a partial list of which is summarized here.



































Research on the utilization of electromagnetic energy for therapeutic purposes, and on 
















health management through information technology is expanding continually, like
















 the use of RF/Microwaves for the treatment of cardiac
















dysfunction, and more recently, through the study of imbedded sensors, and of blue and 
















red LEDs in light therapy. The following list includes some of the many research areas in 
















which microwave techniques have been employed and in which the authors have played a
role:
1. RF and Microwaves in Therapeutic Medicine:
Microwave Balloon Angioplasty
RF/Microwave Cardiac Ablation

















Microwaves in Surgery
Microwave Assisted Liposuction
 Microwave Endometrial Ablation
RF/Microwaves in Pain Management
2. Wireless Microwave Sensing in-vitro, and embedded in-vivo:
Advances in communications have led to increasing developments in telemedicine systems, with 
















the goal of increasing professional care givers' accessibility to a critical patient's-information.
Based on Wireless Communications
Based on Radar Principles
A microwave wireless intracranial pressure sensor (ICPS) for subdural monitoring of 
















pressure in adults and in hydrocephalic children.
3. Thermography: Radiometric Sensing
Microwave Imaging, including MRI
RF/Microwaves for tissue regeneration:

6. Safety Issues of RF/Microwaves
7. The use of Blue Light (475 nm) for jaundice therapy
8. The use of Red Light (650 nm) in photodynamic therapy (PDT)
In researching phototherapy, we investigated the possible therapeutic gains in introducing 
















the optical source adjacent to the target tissue. In the case of PDT, we inserted semiconductor 
















RED Lasers (635 nm) into a balloon catheter for the treatment of Barrett's Esophagus.



































9. The use 700–800 nm LEDs for oxygenation measurements.
& 800 nm LEDs/detectors systems to measure changes in cerebral oxygen levels as a 
















function of hearing. The technique will also be used to investigate pain monitoring and 
















management in neonates.













































































































































































Endoscopic light source for PDT























































Photodynamic therapy (PDT) is a treatment modality using light of an appropriate 





































































































wavelength to activate a photosensitizer in the presence of oxygen, resulting in localized 





































































































tissue necrosis. The depth of light penetration, and consequently of tissue necrosis, is a 





































































































function of light wavelength. Barrett's Esophagus (BE) is one such lesion that is an ideal 

















































































































































































































































































































target for PDT
 . 





































































































It is a lesion of the superficial lining of the esophagus, characterized by the
replacement of the normal stratified squamous epithelium by a metaplastic columnar
epithelium





















































































































































































































































































































A Wireless embedded intracranial pressure monitoring device - implantable
at bed-side

Increased Intracranial Pressure (ICP) caused by brain diseases or head injury is usually the final common cause of permanent disability and death. A major focus is thus required for Fig. 4 (a) Flexible probe used for optode-scalp coupling. (b) Propagation of photons between source and
detector. J Infrared Milli Terahz Waves (2009) 30:1374–1386 1381 measurement and control of ICP for optimum care of both acutely and chronically ill
patients. According to the 2006 Center for Disease Control report, at least 1.4 million people sustain a Traumatic Brain Injury (TBI) every year. Of these, 50,000 die, 235,000 are
hospitalized, 1.1 million are treated and discharged from Emergency Rooms (ER) and about 80,000–90,000 are rendered permanently disabled from their injury. Approximately,
475,000 TBI's occur in children in the age group of 0–14 years. On average, each year, hydrocephalus accounts for over 50,000 hospital admissions, 10,000 people are diagnosed
with brain tumors, and 100,000 have hemorrhagic strokes. The measurement of ICP is critical in the management of such neurosurgical patients. 












































































































The ICP system being developed presently will eliminate the drawbacks encountered by the ICP monitoring techniques used heretofore. A small wireless sensor, operating at 












































































































microwave frequencies, has been implanted in animals just below the scalp. The implantation procedure is considered to be benign enough that it can be performed at 












































































































bedside, rather than requiring an operating room environment. The sensor is located in the subdural space, i.e. between the protective covering surrounding the brain, which also 












































































































contains cerebral spinal fluid. The sensor is completely implantable, small, rugged, likely to survive many non-fatal injuries, and compatible with modern imaging techniques such as 












































































































MRI, CT and the like. Since the monitoring system is not restricted to patients in a hospital setting, ICP could potentially be monitored in ambulatory conditions, where the patient is 












































































































being evacuated from the site of injury to the medical clinic or hospital. Moreover, once the sensor is implanted, ICP can be monitored non-invasively.
In the case of hydrocephalus, the capability to easily, periodically monitor ICP will also facilitate the efficient management of these patients as well. The core technology that will
be accelerated in the proposed system rests primarily with an accurate, reliable, and noninvasive method (once implanted) for monitoring ICP, even if the patient is several feet
away from the measurement receiver. The receiver system could be connected to a computer to track the ICP measurement, recording and transmitting the results to the clinician.
Ultimately, the patient might be able to keep a receiver in his or her bedroom, record data, and periodically send it for review by a clinician, all without leaving home










































































































































































































































































































































http://www.springerlink.com/content/f234560074m64168/fulltext.pdf
Christian Argenis Umaña Zambrano 17678077

Publicado por en
Etiquetas:

1 comentario:

Suscribirse a: Enviar comentarios (Atom)