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PubMed1986

Interlaboratory comparison of ultrasonic attenuation and speed measurements.

A set of test samples, all containing ultrasonically equivalent tissue-mimicking material, was produced and measurements of ultrasonic speed and ultrasonic attenuation coefficients were made at seven laboratories using various techniques. The ultrasonic speed values agree well with one another, having a spread of about 0.3 per cent; thus, speed values for tissue parenchyma appearing in the literature are likely to be accurate. Values of ultrasonic attenuation coefficients agree fairly well with one another, with differences between individual values and the group mean of generally less than 20 per cent of the group mean.

Humans↗
PubMedDate not supplied

[Surgical cryo-ultrasonic instrument].

With the YPCK-7H unit, serving as a base, a cryo-ultrasonic instrument for a combined use of cryogenic and ultrasonic methods has been constructed. A pipe for the passage of liquid nitrogen is mounted on an ultrasonic waveguide, this securing the cooling of the soft tissue subjected to the operation down to--135--80degreesC and separation of the tissues with the frequency of ultrasonic oscillations within a range of 20 to 45 kHz. The surgical cryoultrasonic instrument is apt to significantly increase the efficacy of hemostasis and helps achieve a still better neatness of the cut, this obviously being due to the cryogenic factor which adds advantage to the ultrasonic operative intervention.

Cryosurgery↗
PubMed1989

Ultrasonic cleaning in the hospital.

Ultrasonic cleaning can prolong the life of expensive instruments. In the past, many fine instruments were discarded due to stiffening hinges and box locks, or sticking plungers. Hand scrubbing and spray washing could not thoroughly clean these areas. Ultrasonic cleaners effectively remove dried and baked blood, serums and medications from these instruments. Also, hinged instruments and syringes operate more smoothly during use in surgery when cleaned using ultrasonics. In addition, the use of ultrasonics alleviates the necessity for hand scrubbing of contaminated surgical instruments and laboratory apparatus, a procedure which could lead to injury or infection. The superb cleaning powers of ultrasonic cleaners, their speed and simplicity of operation, and their ability to remove blood, tissue, bacteria and microorganisms within minutes, makes them a valuable addition to any operating room suite, central service department, or emergency room. Their cost-effectiveness is considerable for the small hospital, and compelling for the large hospital.

Central Supply, Hospital↗
PubMed1998

Effect of ultrasonic cleaning on microorganisms.

PURPOSE: To establish a method to measure microbial kill caused by ultrasonic cleaning. Secondarily, to estimate the escape of bacteria from the ultrasonic cleaning solutions during operation of the unit. MATERIALS AND METHODS: Three commercial enzymatic detergents and saline were used as cleaners. Depending on detergent, initial operational temperature was 21 degrees C, 37 degrees C or 60 degrees C. Streptococcus mutans ATCC 25175 (S. mutans suspensions) was adjusted to a final concentration of 1.0 x 10(3) cells/mL in saline. Suspensions (2000 mL) at the desired temperatures were added to the cleaner. Aliquots were removed, serially diluted in letheen broth and spread plated over mitis salivarius agar. Appropriate amounts of detergent solutions were added to S. mutans suspensions and the cleaner operated for 20 minutes. Aliquots were then removed and plated. The process was repeated twice. Plates were aerobically incubated at 37 degrees C for 7 days and the colonies counted. The procedure was repeated using three temperatures of S. mutans suspensions (21 degrees C, 37 degrees C or 60 degrees C), but without detergent or ultrasound. Also, detergents were added to 21 degrees C S. mutans suspensions and allowed to sit for 20 minutes without ultrasonic cleaning. Microbial sampling was done as previously described. RESULTS: Results when ultrasound was used indicated that little kill (5-15%) occurred in 21 degrees C or 37 degrees C detergent solutions. Greater kill (25-35%) was noted with 21 degrees C and 37 degrees C saline. Complete kill was accomplished with 60 degrees C saline or the 60 degrees C detergent solution. When ultrasound and detergent were not used, there was no kill in 21 degrees C and 37 degrees C saline, but complete kill in 60 degrees C saline. In the absence of ultrasound no kill was noted in 21 degrees C S. mutans suspensions to which detergent had been added. Total kill of S. mutans was observed in 60 degrees C saline or 60 degrees C detergent with ultrasound or after a 20-minute exposure in 60 degrees C saline without ultrasonic cleaning. Very few bacteria escaped from the ultrasonic cleaning solutions into the air during the cleaning process. Placement of the unit lid effectively reduced emissions to zero.

Coenzymes↗
PubMed1975

[Ultrasonic diagnosis of liver metastases (author's transl)].

166 patients suspected to harbor metastases in the liver were examined by ultrasonics. The results of this examination could be evaluated in 113 cases, yielding a correct diagnosis in 92%; in 53 cases with uncharacteristic changes of the liver the presence of metastases could be neither proven nor excluded, thus the overall yield of correct results was 72%. In 124 patients ultrasonic findings could be compared with scintigraphic findings (99m-Tc-sulfur colloid): A false diagnosis was made on the basis of ultrasonic findings in 5 cases, on the basis of scintigraphic findings in 18 cases; no conclusive diagnosis could be made by ultrasonic procedures in 34 cases, by isotope scanning in 48 cases. The ultrasonic diagnostics has the advantage of low cost and no risk and allows to differentiate between solid and cystic lesions.

Humans↗
PubMed2002

A novel strategy for cyanobacterial bloom control by ultrasonic irradiation.

The application of ultrasonic irradiation to control cyanobacterial blooms was evaluated in actual eutrophic lake water. Ten prototype units of the Ultrasonic Irradiation System (USIS) were installed in the 32 ha Lake Senba, and the water and sediment quality were monitored for 2 years. By incorporating the ultrasonication process with the on-going strategy, particularly flushing with induction water, cyanobacterial blooms can be controlled effectively. In addition, a significant improvement in the conditions of the lake in terms of chlorophyll-a, COD and T-P was attained. Moreover, the feasibility of ultrasonic irradiation and bacterial assisted control of cyanobacterial blooms was also evaluated in laboratory conditions. The destruction of gas vacuoles brought about by ultrasonic irradiation promoted close contact between cyanobacteria and their lysing Myxobacter leading to immediate and accelerated destruction of the cells.

Cyanobacteria↗
PubMedDate not supplied

The ultrasonic trocar provides an easy, sharp, bloodless, and repeatable approach to the abdominal cavity.

Reusable trocars have the advantage of being more cost-effective than disposable trocars. However, the reusable trocar does lose its sharpness on insertion with repetitive insertion. Nonreusable trocars are expensive, but the sharpness of the knife facilitates insertion. Nonreusable trocars have a safety shield system designed to decrease abdominal organ injury, though the potential problem of bleeding from the abdominal wall port site has yet to be resolved. We therefore developed a novel ultrasonic vibrating trocar that does not lose its sharpness even with repetitive insertion. This trocar prevents bleeding by means of an ultrasonic cavitation effect. The ultrasonic vibrating trocar has the advantage of ease of insertion, and the force required for new reusable trocar insertion was only 34% of the force required for insertion of commercially available nonreusable trocars. The force required for multiply used conventional reusable ultrasonic vibrating trocar insertion, ie, 900 insertions, was maintained at less than 46% of the force required by the corresponding nonreusable trocars. Bleeding from the abdominal wall was prevented by an ultrasonic cavitation effect.

Abdominal Wall↗
PubMed2003

Laparoscopically assisted modified radical vaginal hysterectomy (type II) with pelvic lymphadenectomy: ultrasonic operative technique.

OBJECTIVE: The aim of this study was to incorporate an ultrasonic operative laparoscopic technique to complete a type II laparoscopically-assisted modified radical vaginal hysterectomy (LARVH) and pelvic lymph node dissection (PLND) in early cervical cancer. METHODS AND MATERIALS: LARVH type II and PLND using a laparoscopic ultrasonic operative technique and conventional vaginal surgery were indicated in five cases of early cervical cancer (IA2). RESULTS: Complete pelvic lymphadenectomy and the laparoscopic phase of modified radical vaginal hysterectomy were successfully performed using ultrasonic instruments in all women. Uterine artery and ureteral dissection with resection of the cervicovesical fascia, cardinal and uterosacral ligaments were successful with ultrasonically activated instruments only. CONCLUSION: Our initial experience with laparoscopically assisted radical vaginal hysterectomy type II confirmed that the use of a minimally invasive ultrasonic technique is feasible. Further investigations into the indications of disease where laparoscopic surgery is appropriate in the management of early cervical carcinoma are required.

Adult↗
PubMed2003

[Studies on ultrasonic wave extracting method determining konjac glucomannanin konjac refined powder].

OBJECTIVE: To investigate the effect of ultrasonic wave on extracting Konjac Glucomannan(KGM) in Konjac refined powder. METHOD: Free reduced sugar in Konjac refined powder was removed and Konjac refined powder in the aqueous solution was processed by ultrasonic wave and KGM content was measured by spectrophotometry. RESULT: KGM content in the Konjac refined powder aqueous solution by ultrasonic process at fixed 40 kHz, 100 W, 30-45 min was equal to that by routine method at 4 h; whereas, by 1 h of ultrasonic process, KGM content was significantly enhanced than that by 4 h of routine method(P < 0.01), enhancement rate was 6.5%. Linearity of standard glucose was good (r = 0.9996) in range of 0.2-1.6 mg. The average recovery was 97.8%, RSD of repeatability was 1.27%. CONCLUSION: Ultrasonic extraction in aqueous solution is a reliable and rapid method that can enhance extraction efficiency of KGM in Konjac refined powder.

Amorphophallus↗
PubMed2004

[Total cyst excision with ultrasonic scalpel under the laparoscope for choledochal cyst].

OBJECTIVE: To discuss the technique and its advantage on application of ultrasonic scalpel in laproscopic cyst excision with Roux-en-Y hepatoenterostomy. METHODS: Forty-five cases were undergone laparoscopic cyst excision with Roux-en-Y hepatoenterostomy by ultrasonic scalpel. After intraoperative cholangiogram, the gallbladder and the dilated bile duct were completely excised by ultrasonic scalpel. Roux-en-Y hepatoenterostomy was performed extracorporeally through umbilical incision, then an end-to-side anastomosis was carried out intracorporeally. RESULTS: All 45 cases were completely accomplished under laparoscope combined with ultrasonic scalpel. Median duration of operation was 4.2 h (3.5-6.0 h). Intraoperative bleeding was between 10-50 ml (median 15 ml). No complication were found during operation. All children were discharged in 3-9 d (median 5.5 d) after operation. Thirty-eight cases were followed up 1-18 months. No stenosis or ileus occurred. Liver functions were in normal level. CONCLUSIONS: Total cyst excision with Roux-en-Y hepatoenterostomy by ultrasonic scalpel under the laparoscope was effective and safe for choledochal cyst. The most excellence was that clearly viewing during operation, less bleeding and injury, free of pain postoperation, microincision and scar.

Anastomosis, Roux-en-Y↗
PubMed2004

Dentinal crack incidence following ultrasonic vibration to intra-radicular posts.

OBJECTIVE: To determine the incidence of dentinal cracks on the root-face of extracted teeth containing intra-radicular posts subjected to prolonged ultrasonic vibration. Design & Setting This in-vitro experiment, conducted at the University of Manchester, UK, used post type and ultrasonic vibration as dependent variables. MATERIALS AND METHODS: Forty canine teeth were decoronated and root-filled with gutta-percha and sealer. A parallel shaped post-space of 1.4 mm diameter and 10 mm depth was prepared in each root. The teeth were grouped into morphologically similar pairs, and for each pair one tooth was randomly allocated to receive a zirconium ceramic post, the other a stainless steel post. The pairs of teeth were randomly assigned to a control or to a test group. The root-face was examined for dentine cracks or fractures with direct vision and at 20x magnification with transillumination. Samples were then stored in sterile water for one week. Ultrasonic vibration was applied continuously for 30 minutes to the top of the posts in the test groups. All samples were then re-examined for dentine cracks or fractures. RESULTS: Following storage, no new cracks were evident for the control groups. Seven new cracks occurred in the test groups (following application of ultrasonic vibration), six of which were on the root-face of samples with ceramic posts. The difference in crack distribution between the two groups was significant (Fisher's Exact Test, p=0.029). CONCLUSION: Prolonged application of ultrasonic vibration to ceramic posts increased the incidence of root-face cracks.

Ceramics↗
PubMed2004

[Clotting induction in the mesenterium and erosive stomach mucosa in wistar rats as the result of a catenoidal ultrasonic transducer].

The ultrasonic transducers and instruments used in surgery operate in the range of 1-10 MHz and release significant heat in the surroundings. They need additional cooling system which significantly raises the cost and impedes the equipment operation. Hemostasis can be successfully achieved by employing ultrasonic transducers that operate in the kilohertz range, avoiding the occurrence of inadmissible tissue overheat outside the area of the transducer performance. The paper presents results of the approbation of the effect of a periodical acoustic signal with frequency of 60 kHz over the erosive stomach mucosa and mesenterium of 28 rats, "Wistar" breed, and the period of tissue exposure is 1-10 min. A transducer-catenoidal semi-wave concentrator that provides maximum emitted power of the ultrasonic wave is used and thermal effects are avoided. It is proved that the use of a powerful and localized ultrasonic signal results in erythrocyte diapedesis and forms microhaemorrhagies together with an out-vessel coagulation in the rat stomach mucosa The tissue damages are strictly limited within the area of the emitter contact and they are subject to control during the ultrasonic performance.

Animals↗
PubMed1991

Comparison between cholinergically and naturally induced ultrasonic vocalization in the rat.

Ultrasonic vocalization in rats accompanying stressful situations or induced by direct brain stimulation may be used as a measure of emotionality and as a potential response model for testing anti-anxiety agents. The aim of the present study was to compare physical features of pharmacologically-induced ultrasonic vocalization with naturally triggered vocalization. Ultrasonic calls induced by hand touch, footshock, or by direct intracerebral injection of carbachol in adult rats were compared. Ultrasonic calls obtained in all these situations were described as '22 kHz' vocalization. Average frequencies of vocalization were 24.1 +/- 0.78 kHz, 26.0 +/- 2.64 kHz and 25.0 +/- 1.87 (SD) kHz for handled, footshocked and carbachol injected rats, respectively, and they did not differ significantly from each other. Histograms of single call duration showed similar distribution patterns for all groups with a predominance of long calls, although carbachol-induced calls were shorter than calls induced by touch or footshock. Histograms for inter-call intervals showed one major peak at 100-150 ms for all groups. Sonograms and power spectra showed similar characteristics both for calls induced by intracerebral carbachol and by hand touch or footshock. The results indicate that physical features of ultrasonic vocalization induced by intracerebral carbachol are comparable with those for naturally induced vocalization and fall into the category of '22 kHz' calls.

Animals↗
PubMed1978

[Removal of intravascular thrombi by means of ultrasonics. Experimental study with a new method and its clinical use].

A new method of destroying thrombi in blood vessels by ultrasound and simultaneously removing them is reported. Experiments were performed in 19 dogs with artificial thrombi in the iliac and the femoral arteries and veins. The length of the thrombi ranged from 4 to 5 cm and the age from 12 h to 9 days. The unit used consisted of a generator, a frequency counter, an ultrasonic transducer with the hollow waveguide, and a vacuum pump. For protection of the vessel wall the guide is surrounded by a plastic tube. The ultrasonic frequency is 26.5 kHz, the amplitude 25--30 micrometer. The time needed to destroy the thrombus by ultrasound and suck out the thrombotic material ranged from 2.5 to 5 min. To check side effects, experiments were performed in 48 dogs. No changes resulting from ultrasonic irradiation were seen in the circulating blood or in the microscopic structure of the vessel wall. Ultrasonic thrombolysis was performed in a 42 year old patient with a 2-day-old thrombosis of the femoral artery. After 4.5 minutes of intermittent ultrasonic irradiation the artery was patent.

Animals↗
PubMed1980

[Effects of ultrasonic irradiation on chromosomes, cell division and developing embryos (author's transl)].

These experiments were planned to acquire any informations about the possibilities of harmful effects of ultrasonics on the chromosomes, the cell division of cultured cells and the developing embryos of the ICR mice. 1. The effects of ultrasonics on the chromosomes. Lymphocytes of fetal blood, fibroblasts of fetal skin and fibroblasts from amniotic fluid were exposed to the continuous ultrasonics of 2MHz with the intensity of 2W/cm2, 1 hour. No significant increase of chromosomal aberrations was found in the exposed groups. 2. The effects on the growth of cultured cells. Fibroblasts of fetal skin were exposed to the continuous ultrasonics of 2MHz (max 2MHz, 2 hours). The cell growth was observed during 14 days, but no suppression on the cell division appeared in the exposed groups. 3. The effects on the ICR pregnant mice. In total, 125 ICR pregnant mice were exposed to the ultrasonics of 2MHz on 8th day of pregnancy (I; control group, II; buffered control group, III; 200 mw/cm2 and IV; 2000 mw/cm2, 5 min). The weight gain of maternal body was suppressed in group IV. The number of implantation sites in group IV was significantly higher than the other 3 groups. The external, skeletal and visceral abnormalities were examined for 1251 fetuses. Brain hernia, anencephaly, cleft palate and skeletal abnormalities were found in group IV and its incidence was significantly higher than the other 3 groups.

Animals↗
PubMedDate not supplied

Ultrasonic dissection in combination with high-frequency surgery.

Ultrasonic surgery is a technique used for tissue-selective dissection. High-frequency surgery, on the other hand, is a technique which permits largely non-selective cutting of all tissue except bone. Whereas ultrasonic surgery has no haemostatic effect, high-frequency surgery is highly effective for haemostasis. The combined use of ultrasonic surgery and high-frequency surgery, particularly in endoscopic operations, can unite the advantages of both methods and thus improve surgical techniques or even permit applications which are difficult or impracticable with ultrasonic surgery or high-frequency surgery alone. Various possibilities for combining ultrasonic surgery and high-frequency surgery have not been exploited to date and therefore remain open for future development.

Dissection↗
PubMed1993

Microstructure and strength analysis of ultrasonically shaped ceramics.

In this study, the influence of a new ultrasonic shaping procedure on the surface quality, microstructure, bending strength and fatigue behaviour of a feldspathic porcelain was investigated. A total of 120 standardized (ISO 6872) autoglazed, ground, lapped and ultrasonically machined porcelain test bars were analyzed. Another 24 equiformat experimental alumina ceramics, which were ultrasonically machined, as well as 24 nontreated fload glass specimen served as controls. It could be shown that the porcelain removal process with diamond grinding wheels yielded a rough surface microrelief and lead to structural subsurface damage, decreasing bending strength and fatigue behaviour. In contrast, ultrasonic shaping resulted in a smoother surface and prevented damage to the subsurface layer of the machined brittle porcelain, although, the smoothest surfaces were achieved by lapping. Both bending strength and fatigue behaviour of the conventional dental porcelain were increased by ultrasonic machining. However, the fracture toughness of the experimental alumina was substantially higher and was not subjected to a decrease in fatigue.

Aluminum Oxide↗
PubMedDate not supplied

Effect of repeated sterilization and ultrasonic cleaning on curet blades.

PURPOSE: Instrument cleaning and sterilization are important steps in infection control. This study investigated the effect of repeated ultrasonic cleaning, cycles of autoclave or chemiclave, on the surface and cutting edge of stainless steel and carbon steel curets. METHODS: Eight carbon steel and six stainless steel Columbia #13/14 curets were cleaned or sterilized in a series of treatments by one of the following methods: ultrasonic cleaning, chemiclave sterilization, and autoclave sterilization. In addition, two carbon steel instruments were placed in an anticorrosive dip followed by autoclave. The blades of the curets were examined and photographed with the scanning electron microscope (SEM) at 200 X and 1000 X for baseline and after 2, 4, 8, 16, and 32 treatment cycles. Photographs were evaluated for visible change in surface appearance by four examiners independently. Photographs for each treatment time were compared to the baseline (pretreatment) photographs for the same instrument. They were scored as (1) no visible change; (2) slight change; or (3) moderate to major change. Changes observed were: surface pitting, corrosion products as additions to the surface, edge deterioration, or loss of structure. RESULTS: Stainless steel curets showed slight or no change after the three treatments. Carbon steel curets were affected by all treatments. The chemiclave produced slight change. The autoclave produced slight change after the fourth treatment cycle and moderate to major change after the eighth cycle. Those carbon steel instruments treated by anticorrosive dip followed by the autoclave showed pronounced change after 16 or 32 cycles. The most varied results were from the ultrasonic cleaner; one blade showed moderate to major change after only four cycles, the other showed slight change at that point and major change only after 32 cycles. CONCLUSION: With stainless steel curets, ultrasonic cleanings or sterilization with autoclave or chemiclave can be used without visibly affecting the cutting edge. With carbon steel instruments, chemiclave is the least damaging sterilization method followed by anticorrosive treatment before autoclaving. Use of the autoclave without the anticorrosive pretreatment or use of an ultrasonic cleaner negatively affects the integrity of the surface and cutting edge of these instruments.

Corrosion↗