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At least 181 records · Page 10Linked to original sources

PubMed2006

Radiofrequency surgery--novel techniques in the treatment of ano-rectal disease.

BACKGROUND: Radiofrequency surgery is a method of utilizing high frequency (3.8 to 4MHz) radio wave energy to incise, excise, or coagulate tissues. Radiofrequency (RF) is a relatively new modality that is being used for ano-rectal surgeries with increasing frequency. As the RF energy is applied, frictional heating of tissues results, with cell death occurring at temperatures between 60 and 100 degrees C. OBJECTIVE: This paper discusses author's clinical experience with radiofrequency for various ano-rectal pathologies namely hemorrhoids, anal fistula, anal polyps, sinuses and anal papillae. A Ellman dual frequency radiofrequency generator was used to carry out the procedures. This study is intended to be somewhat of a "how we do it" manual, explaining the principles of radiofrequency. CONCLUSION: Radiofrequency proctological procedures are simple to perform with many advantages over the more traditional techniques. The procedures take less operative time, the postoperative recovery is accelerated and the incidences of complications are negligible.

Anus Diseases↗

PubMed1997

Noninvasive blood glucose monitoring.

The concentration of glucose in the blood may soon be measured noninvasively, without puncturing the finger to obtain a drop of blood. Current prototype devices for this purpose require greater accuracy and miniaturization to be commercially viable. No such device has been approved for marketing by the U.S. Food and Drug Administration. The technology used for noninvasive blood glucose monitoring involves either radiation or fluid extraction. With radiation technology, an energy beam is 1) applied to the body, 2) modified proportionate to the concentration of glucose in the blood, and 3) measured. The blood glucose concentration is then calculated. With fluid extraction technology, a body fluid containing glucose in a concentration proportionate to the blood glucose concentration is extracted and measured. The blood glucose concentration is then calculated. The most promising technologies are 1) near-infrared light spectroscopy, 2) far-infrared radiation spectroscopy, 3) radio wave impedance, 4) optical rotation of polarized light, 5) fluid extraction from skin, and 6) interstitial fluid harvesting. Each method has features predictive of commercial viability, as well as technical problems to overcome.

Blood Glucose↗

PubMed1995

Utility of cerebral proton magnetic resonance spectroscopy in differential diagnosis of HIV-related dementia.

Opportunistic infections often coexist with human immunodeficiency virus (HIV) infection in brain. Making the correct diagnosis is often difficult despite recent advances in neuroimaging techniques. 1H magnetic resonance spectroscopy (1H MRS) is an emerging non-invasive examination for diagnosis and monitoring of brain disorders. 1H MRS measures a variety of organic compounds using magnetism and radio waves. Biochemical aberrations in brain, not shown by conventional tests, may be demonstrated by 1H MRS testing. A patient coinfected with HIV and hepatitis B (HBV) presented with progressive dementia. Clinical, neuroradiological and cerebrospinal fluid (CSF) examinations failed to provide a diagnosis in support of either HIV-1-associated cognitive/motor complex or HBV-induced hepatic encephalopathy (HE), 1H MRS was used in an attempt to discriminate between these diagnoses. Spectroscopy demonstrated increased glutamine and normal N-acetyl aspartate (NAA) levels, metabolic changes consistent with HE. These findings were later confirmed pathologically. Proton magnetic resonance spectroscopy is a non-invasive test with utility for the differential diagnosis of HIV-associated dementia.

AIDS Dementia Complex↗

PubMed1994

Blepharoplasty and ptosis.

Recent advances in local anesthetic techniques have led to suggestions that buffered solutions for infiltration increase patient comfort. The use of an eutectic mixture of local anesthetics cream has however proved to be disappointing. The use of monopolar electrocautery, carbon dioxide lasers, and high-frequency radio wave electrosection provide the surgeon with new modes of cutting and coagulation. Lower lid blepharoplasty via a conjunctival approach may avoid many of the complications of the anterior approach. Such complications may also be minimized by careful preoperative planning and frequently the inclusion of a lateral canthopexy in the surgical procedure. The lid height after anterior and posterior levator resection can now be set more accurately with adjustable suture techniques. A new technique combining a superior tarsectomy with levator resection is described. A range of materials for brow suspension are now available. Autogenous fascia lata remains the material of choice when available.

Anesthesia, Local↗

PubMed2000

NOAH--A mobile emergency care system.

Experiencing communication problems in our emergency services, we developed an innovative communication network and system the NOAH-system (NOAH, which stands for Notfall -, Organisations - und Arbeitshilfe or Emergency-Organisation Active Aide System). In contrast with the currently established emergency services communication in Germany by radio wave, data is transferred from the scene in the form of an electronic record on a mobile computer by means of the wireless data communication network Modacom (Mobile Data Communication), which is provided by German Telekom. It is received at the dispatch-centre in mentioned format and transferred to the admitting hospital without any loss of data. - In a prospective study, the technical and conceptual suitability of this system was investigated. It was shown that an admitting hospital was informed more than 20 minutes in advance about the admittance of a patient. To assure the quality of transferred data, information was ranked by different criteria. This further demonstrated that much more precise information about a patient's condition was already available upon admittance in the hospital.

Emergency Medical Services↗

PubMed1999

NOAH. A mobile emergency care system. Notfall-Organisations- und Arbeitshilfe.

Experiencing communication problems in our emergency services, we developed an innovative communication network and system (NOAH, which stands for Notfall-Organisations- und Arbeitshilfe, or Emergency-Organisation Active Aide System). In contrast with the currently established emergency services communication in Germany by radio wave, data is transferred from the scene in the form of an electronic record on a notepad-computer by means of the wireless data communication network Modacom (Mobile Data Communication), which is provided by German Telekom. It is received at the dispatch-centre in mentioned format and transferred to the admitting hospital without any loss of data. In a prospective study, the technical and conceptual suitability of this system was investigated. It was shown that an admitting hospital was informed more than 20 minutes in advance about the admittance of a patient. To assure the quality of transferred data, information was ranked by different criteria. This further demonstrated that much more precise information about a patient's condition was already available upon admittance to the hospital.

Emergency Medical Services↗

PubMed2000

Cold stress, near drowning and accidental hypothermia: a review.

This paper reviews literature on the topic of cold stress, near-drowning and hypothermia, written mainly since the last review of this type in this journal. The main effects of cold stress, especially in cold water immersion, include the "cold shock" response, local cooling causing decrements in physical and mental performance, and ultimately core cooling as hypothermia occurs. The section on cold-water submersion (near-drowning) includes discussion regarding the various mechanisms for brain and body cooling during submersion. The mechanisms for cold-induced protection of the anoxic brain are discussed with attention given to decreased brain temperature and the Q10 principle, the mammalian dive reflex and a newly considered mechanism; cold-induced changes in neurotransmitter release (i.e., glutamate and dopamine). The section on the post-cooling period includes the post-rescue collapse and subsequent rewarming strategies used in the field, during emergency transport or in medical facilities. Recent research on topics such as inhalation warming, body-to-body warming, radio wave therapy, warm water immersion, exercise, body cavity lavage, and cardiopulmonary bypass is reviewed. Information on new methods of warming, including arteriovenous anastomoses (AVA) warming (by application of heat- with or without negative pressure application-to distal extremities in an effort to increase AVA blood flow), forced-air warming, and peripheral vascular extracorporeal warming, are discussed.

Accidents↗

PubMed2001

[Radiochemotherapy plus hyperthermia in rectal carcinoma].

In locally advanced rectal cancer (uT3/uT4) resectability as well as local control is reduced. In the patients combined preoperative radiochemotherapy demonstrated an increase of resectability and a reduction of local recurrence. Radiotherapy was applied in standard blocks, 5 x 1.8 Gy up to 45 Gy. Chemotherapy consisted out of two cycles of 5-Fluorouracil (300-350 mg/m2/d) and Leucovorin (50 mg). Prior to radiotherapy additionally thermotherapy was carried out using the SIGMA 60 applicator BSD 2000 once a week. The hyperthermia method is based on heating up affected tissue compartments to temperature above 42 degrees Celsius without damaging surrounding tissue compartments. In regional hyperthermia tumors in the abdominal region are treated by emitting radio waves into the patient. 4-6 weeks after radiochemotherapy, surgery was performed. The therapeutic toxicity was acceptable and the resectability rate was up to 90%. Response rate to treatment was 60%. Our data with preoperative combined treatment in locally advanced rectal cancer revealed encouraging downstaging, local control, and survival rates.

Chemotherapy, Adjuvant↗

PubMed2000

Telehealth in the Pacific Islands: a perspective and update from the Fiji School of Medicine.

The Fiji School of Medicine (FSM) has increased participation with telehealth/telemedicine in general, and specifically with the Pacific Public Health Surveillance Network (PPHSN) and the Western Pacific HealthNet(WPHNet), through the establishment of a WPHNet Centralised Triaging Service (CTS). The FSM Telehealth/Telemedicine Unit (FSMTU) will oversee the development of the CTS which is being closely coordinated with existing clinical consultation services provided through Project Aamai and the Tripler Regional Medical Center (TRMC). While the WPHNet CTS will initially be concerned with distance clinical consultation, the FSM mission encompasses community health and professional health education in a wide range of disciplines. Currently, WPHNet only serves the jurisdictions of the US-associated Pacific islands but with WPHNet CTS there will be an opportunity to include new member jurisdictions that do not have political affiliation with the USA. (e.g. Cook Is, Kiribati, Niue, Samoa, Solomon Is, Tonga, Vanuatu etc). In addition, although Internet technology is expanding rapidly in the region, the capacity for outside communication throughout the Pacific is quite varied. Very remote areas may currently only be able to communicate by using short wave radio. Others have telephone and/or fax while some have E-mail but not full internet capacity. The FSMTU will implement mechanisms to field requests through any of these communication avenues and so the WPHNet CTS will serve as a proxy for regional healthcare providers that do not have internet access.

Fiji↗

PubMed2002

Functional electrical stimulation in tetraplegic patients to restore hand function.

The purpose of this collective review is to describe a new form of functional electrical stimulation called neuroprosthesis. This unique technology has been devised to produce lateral pinch and palmar grasp in persons with C5 and C6 motor level spinal cord injuries. This neuroprosthesis includes external as well as implanted components. First, a receiver is surgically implanted into the patient's chest above a pectoralis major muscle. The receiver stimulator is then connected to 8 surgically implanted epimysial or intramuscular electrodes. Restoration of upper extremity function can greatly improve the lives of people affected with tetraplegia. When contralateral shoulder movements trigger an external transmitting coil, it sends a radio wave impulse to the stimulator inducing contraction of the muscles. Many tetraplegics are regaining hand function using implanted functional electrical stimulation. One major limitation is that the key muscles to be stimulated may have lower motor neuron damage, but this obstacle has been successfully overcome using surgical modifications of the biomechanics of the hand.

Activities of Daily Living↗

PubMed2003

[Core body temperature monitoring using the telemetric pill].

Exposure to extreme weather or physical work conditions can lead to dangerous core temperature changes, and to the clinical syndromes accompanying them. Core temperature measurement is the main tool for diagnosing these syndromes. Recent technological advances particularly NASA's telemetry and miniaturizing technologies, have led to the development of a CorTemp Ingestible Temperature Sensor, or "pill". The pill is a small electronic device, which senses the body's temperature and transmits it through a radio wave signal to an external receiver. The advantage of the pill over other temperature measurement devices is that it is a simple device that enables core temperature measurement for many hours without the need of any wire connections or other cumbersome instruments. For this reason, the pill is an ideal tool for core temperature measurements in field locales or for continuous long duration temperature monitoring of ambulatory patients. The following study reviews available literature concerning the use of the pill and the validity of its measurements. A high correlation has been revealed between pill temperature measurements and rectal or esophageal measurements. Pill temperature values usually fall between the high rectal and the low esophageal measurements, considered the gold standard for core temperature measurement. A number of studies emphasizing the advantage of the pill are presented in this review.

Administration, Oral↗

PubMed2003

[Radiofrequency ablation in patients with persistent atrial fibrillation undergoing mitral valve replacement].

The most frequent arrhythmia is an atrial fibrillation, which involves 10% of population over 70. The mortality in this group is 2 times higher than in general population. Moreover, if the atrial fibrillation co-exists with the rheumatic disease, the risk of the brain embolism is growing up 17 times. In the many European medical centers, intraoperative ablation is the obligatory procedure performed during mitral valve replacement/mitral valvuloplasty or coronary artery bypass grafting. Results of that procedure (in experienced centers) are evaluated on 75%. It reduces significantly the cost of the farther pharmacological treatment and improves the quality of life of the patients. In our Clinic ablation is performed in patients qualified to the mitral valve replacement or mitral valvuloplasty. All procedures are performed in extracorporeal circulation, in general and local hypothermia, with using crystal cardioplegine. Before the clumping of the aorta, on the beating heart ablation in the right atrium is performed. After that, the aorta is being clumped and the heart is being stopped. The left cardiac auricle is being cut off. Then the ablation around the ostia of the pulmonary veins is being done. After that, mitral valve replacement or mitral valvuloplasty procedure is being performed. Changes in the heart wall are transmural through the full wall. From the December 2001 till today 4 ablation procedures were done. Units Cobra (Boston Scientific) and Cardioblate Surgical Ablation System (Medtronic) were used. Both units are based on the unipolar energy with frequency similar to the radio-waves. After this procedure, regular rhythm came back in our 4 patients. Advantages of the intraoperative ablation are: simultaneous procedure with open heart operation, reduction of the price of the treatment, minimal risk of complication.

Aged↗

PubMed2005

Radiofrequency coagulation: a new option in early grades of bleeding hemorrhoids.

BACKGROUND: The treatment for hemorrhoids has undergone significant changes on introduction of new techniques in the last few years. Radiofrequency coagulation is a new approach for treating grades I and II of hemorrhoids. In this procedure, the hemorrhoidal tissue is coagulated by means of high-frequency radio wave. The author has described his own experience with this new technique. MATERIALS AND METHODS: The procedure was performed using an Ellman radiofrequency generator. Over a period of 18 months, patients with bleeding hemorrhoids were treated with this technique and a 16-month follow-up was carried out to assess relief in bleeding episodes, complications, and recurrence rate. RESULTS: While 13 % of patients had persistent or recurrent bleeding, 2 % of patients needed readmission for secondary hemorrhage. None had reported with any infective complication. The overall ratio of comfort, and patient's satisfaction due to relief of pain and bleeding were quite satisfactory. CONCLUSION: The treatment of bleeding hemorrhoids by using radiofrequency coagulation is technically simple, therapeutically effective and virtually complication-free. The equipment is portable, easy to handle, durable, and needs little maintenance. Long-term follow-up is necessary to justify the reliance on this method (Ref. 49).

Adult↗

PubMed2006

Radiofrequency coagulation: a new option for early grade bleeding hemorrhoids.

BACKGROUND: The treatment of hemorrhoids has undergone significant changes after introduction of new techniques during last years. Radiofrequency coagulation is a new approach for treating grade I and II hemorrhoids. In this procedure, the hemorrhoidal tissue is coagulated by a high frequency radio wave. The author describes his experience using this new technique. MATERIALS AND METHODS: The procedure was performed using an Ellman radiofrequency generator. Over a period of 18 months, patients with bleeding hemorrhoids were treated with this technique and a 16 months follow-up was carried out to assess a relief in bleeding episodes, complications, and recurrence rate. RESULTS: While 13% of patients experienced persistence or recurrence of bleeding, 2% of patients needed readmission for secondary hemorrhage. None has reported an infective complication. Overall ratio of comfort and patient contentment with pain and bleeding was satisfactory. CONCLUSION: The treatment of bleeding hemorrhoids using the radiofrequency coagulation is technically simple, therapeutically effective and virtually complication free. The equipment is portable, easy handling, long lasting, and needs only little maintenance. Long-term follow-up is necessary to justify reliability of this method (Ref. 49).

Adult↗

PubMed1990

In vivo NMR spectroscopy: investigation of brain metabolism in neonates and infants.

Magnetic resonance imaging (MRI) is a noninvasive investigation technique that uses non ionizing radio waves of low quantum energy, rendering it suitable for application in children. Monitoring and anesthesia techniques allow MRL including immobilisation in a special incubator to be carried out in small infants. In vivo magnetic resonance spectroscopy (MRS) provides biochemical information on living organisms in a non-invasive manner. Such a technique has recently been used to study neonatal brain energy metabolism. High energy phosphate metabolism and phospholipid metabolism can be evaluated in this manner and available clinical correlations can be made regarding eg seizures or long term neurologic sequelae associated with a decreased phosphocreatine: orthophosphate ratio. Future trends in neonatal MRS will provide further information on morphologic and metabolic brain development.

Aging↗

PubMed1990

Field orientation effects during 5.6-GHz radiofrequency irradiation of rats.

Ketamine-anesthetized Sprague-Dawley rats were exposed in E and H orientations (long axis parallel to electric and magnetic fields, respectively) to far-field 5.6-GHz continuous-wave radio-frequency radiation (RFR). Power densities were used that resulted in equivalent whole-body average specific absorption rates of 14 W/kg in both orientations (90 mW/cm2 for E and 66 mW/cm2 for H). Irradiation was conducted to increase colonic temperature by 1 degree C (from 38.5 to 39.5 degrees C). During experimentation, arterial blood pressure and respiratory rate and colonic, tympanic, left and right subcutaneous (sides toward and away from RFR source), and tail temperatures were continuously recorded. Results showed no significant difference in the times required to cause a 1 degree C increase or to recover to the initial temperature when irradiation was stopped. Significant differences between E- and H-orientation exposure were seen in the patterns of localized heating. The tail and left subcutaneous temperature increases were significantly greater during E-orientation exposure, the tympanic site showed no difference, and the right subcutaneous temperature increase was significantly greater during H-orientation exposure. Under both exposure conditions, heart rate and mean arterial blood pressure significantly increased during irradiation; however, there were no significant differences between E and H orientation responses. These findings at 5.6 GHz are in contrast to the significant cardiovascular response differences between E- and H-orientation exposure noted during a previous study of irradiation at 2.45 GHz.

Animals↗

PubMed1989

[The value of a high-frequency bistoury in plastic surgery].

In contrast with the usual electric spark gap scalpels which burn and carbonise tissues, making them unsuitable for section or fine dissection, Surgitron, which uses high frequency radio waves, cuts and coagulates without excessive heating and without carbonisation. It possesses 4 types of current, all with adjustable power levels: section, section-coagulation, coagulation and fulguration. It can be used with ordinary scalpel blades or with the electrodes supplied with the apparatus. It can be used in all stages of the operation: skin incision, fine dissection, coagulation and allows an appreciable gain in time combined with great comfort for the user and for the patient with a reduction in postoperative oedema.

Electrosurgery↗

PubMed1989

A simple anaesthetic and monitoring system for magnetic resonance imaging.

Clinical magnetic resonance imaging (MRI) is a digital tomographic technique which utilizes radio waves emitted by hydrogen protons in a powerful magnetic field to form an image of soft-tissue structures and abnormalities within the body. Unfortunately, because of the relatively long scanning time required and the narrow deep confines of the MRI tunnel and Faraday cage, some patients cannot be examined without the use of heavy sedation or general anaesthesia. Due to poor access to the patient and the strong magnetic field, several problems arise in monitoring and administering anaesthesia during this procedure. In this presentation these problems and their solutions, as resolved by our institution, are discussed. Of particular interest is the anaesthesia circuit specifically adapted for use during MRI scanning.

Anesthesiology↗