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PubMed1997

Ultrasonic tonsillectomy: rationale and technique.

Dissection using ultrasonic aspiration is characterized by its unique tendency to spare fibrous and vascular structures during removal of parenchymal lesions. This preliminary study was undertaken to evaluate the feasibility and efficiency of tonsillectomy using the ultrasonic aspirator. Tonsillectomy was performed on 23 patients using the ultrasonic aspirator. Pericapsular removal of the tonsil was easily accomplished with complete preservation of the tonsillar pillars and minimal peritonsillar trauma. The ability to identify significant vasculature before transection, and the constant aspiration integrated into the ultrasonic aspirator allowed excellent visualization of the operative field at all times. No postoperative complications were noted and recovery was typical for tonsillectomy patients. The ultrasonic aspirator may increase the efficiency and margin of safety of tonsillectomy.

Adolescent↗
PubMedDate not supplied

Ultrasonically induced cell damage enhanced by photofrin II: mechanism of sonodynamic activation.

UNLABELLED: Ultrasonically induced cell damage and active oxygen generation with photofrin II (PF) were compared in the same in vitro insonation setup. MATERIALS AND METHODS: Sarcoma 180 cells suspended in air-saturated PBS were exposed to ultrasound for up to 60 seconds in the presence and absence of PF. The viability was determined by the Trypan Blue exclusion test. Ultrasonically induced active oxygen generation in the presence and absence of PF in air-saturated aqueous solutions of 50 mM 2,2,6,6-tetramethyl-4-piperidone was detected by electron spin resonance (ESR) spectrum. RESULTS: Significant enhancement of the rates of both ultrasonically induced cell damage and nitroxide generation was demonstrated with 20-80 micrograms/ml PF. Both rates correlated very well. The enhancement of both rates with PF was suppressed by 10 mM histidine. CONCLUSION: These results may suggest that ultrasonically generated active oxygen plays a primary role in ultrasonically induced cell damage in the presence of PF.

Animals↗
PubMed2006

[Scanning electron microscopic study on the use of traditional Chinese medical irrigant in ultrasonic root canal instrumentation].

PURPOSE: To evaluate the cleaning ability of traditional Chinese medicine Jieeryin used as ultrasonic root canal irrigant. METHODS: A total of 20 extracted human single-rooted teeth were divided into 4 groups: normal saline, 3.33% Jieeryin, 30% Jieeryin and 2.5% sodium hypochlorite. After ultrasonic root canal preparation a 15#-K type ultrasonic file was inserted into the root canal without contacting the root canal wall and the ultrasonic irrigation was kept for 10 seconds. The cleaning of the cervical, middle and apical thirds of the root canal walls was evaluated by scanning electron microscope. The data were analyzed statistically by ANOVA and Bonferroni test. RESULTS: The cleaning ability of 30% Jieeryin was similar to that of 2.5% NaClO (P>0.05) in the cervical third, and it was significantly better than 3.33% Jieeryin (P<0.01) and normal saline (P<0.05). There was significant difference between the cervical third and the middle or apical thirds (P<0.01) of 30% Jieeryin. There was no significant difference between the four groups in the middle third (P>0.05). In the apical third, 2.5% NaClO was significantly better than normal saline (P>0.05). No significant difference was found between 3.33% Jieeryin and saline in all thirds. CONCLUSION: Cleaning by 30% Jieeryin or 2.5% NaClO with ultrasonic technique was superior compared to the cleaning by 3.33% Jieeryin or normal saline in the cervical third.

Dental Pulp Cavity↗
PubMed2005

Ultrasonic glossectomy--simple and bloodless.

BACKGROUND: The aim of the study was the evaluation of the feasibility of glossectomy using an ultrasonic-activated surgical instrument. METHODS: This was a prospective study of 13 consecutive patients who underwent glossectomy (12 partial and one total) for carcinoma of tongue with the use of ultrasonic scissors. RESULTS: All 13 patients had glossectomy, with median blood loss of 0 mL. The glossectomies were done with an ultrasonic dissector alone. None of the glossectomies required diathermy, ligature, plication, or other methods for hemostasis. The lingual artery and veins of all 13 patients were controlled by use of the ultrasonic scissors alone. No operative complications occurred, including bleeding or wound healing problems. CONCLUSIONS: The excellent combination of coagulation and the cutting effect of ultrasonic scissors has made glossectomy a simple and bloodless procedure. It is a recommended surgical technique in our surgical armamentarium.

Adult↗
PubMed1978

Television synchronization of a real time ultrasonic sector scanner.

The interaction of the scan rates of ultrasonic scanning and television recording systems often causes portions of the resultant television image to be either over- or under-scanned. This results in objectionable bright and dark sectors within the ultrasonic image on a television monitor during single-frame playback. The usual method for dealing with this problem is to exchange time resolution for image quality when preparing pictures for analysis or presentation. Time resolution can be preserved by operating the ultrasonic scanner at a scan rate one-half of the television frame rate and phase locking the ultrasonic scanner to the television system so that each angular scan of the ultrasonic system is initiated coincident with the beginning of each television frame.

Humans↗
PubMedDate not supplied

Ultrasonic characterization of blood during coagulation.

Recently ultrasound has been found to be extremely useful in detecting intracardiac thrombi as well as intracranial hemorrhages in neonates. The principal criterion used for clinical diagnosis of thrombus has been an increase in the echogenicity of clotted blood. However, echogenicity is a rather nonspecific and qualitative description of tissue ultrasonic properties. A rise in echogenicity could be the result of an increase in ultrasonic backscatter, or a decrease in attenuation, or a combination of both. In order to ascertain the mechanism responsible for the clinically observed increase in echogenicity and thus put the technique on a firm foundation, we have measured serially the ultrasonic velocity, attenuation and backscatter in human blood up to 24 hours following the onset of coagulation. Preliminary results show that all three ultrasonic properties increase during this time period. At 24 hours following clotting, the mean rises in velocity, attenuation and backscatter are 3.36 +/- 0.35 X 10(3) cm/sec, 2.3 +/- 0.22 db/cm and 18.5 +/- 1.2 dB per unit volume of blood (at 7.5 MHz and a temperature of 23 degrees C), respectively. These results indicate that the increase in echogenicity of a thrombus is due to a substantial increase in ultrasonic backscatter, which is moderated to a certain extent by the accompanied increase in attenuation.

Acoustics↗
PubMed1981

Haloperidol and clonidine increase, and apomorphine decreases ultrasonic vocalizations by gerbils.

Ten psychotropic drugs that have putative effects on central brain neurotransmitters were assessed for influences on ultrasonic signaling relative to general activity in male Mongolian gerbils. Haloperidol (1 mg/kg IP), a dopamine antagonist, and clonidine (0.1 mg/kg IP), a norepinephrine agonist, increased ultrasonic signaling, and apomorphine (5 mg/kg IP), a dopamine agonist, decreased ultrasonic signaling. Catecholamines may modulate ultrasonic signaling in the gerbil. Body temperature changes were positively with ultrasonic emission in tests after saline, haloperidol, apomorphine, and 5-hydroxytryptophan (30 mg/kg IP).

5-Hydroxytryptophan↗
PubMed2002

Laparoscopic cholecystectomy by ultrasonic dissection without cystic duct and artery ligature.

BACKGROUND: Laparoscopic cholecystectomy (LC) is the gold standard treatment of gallstones. Nevertheless, there are some pitfalls due to the limits of current technology and the use of inappropriate ligature material, with a relevant risk of injuries and postoperative, mainly biliary, complications. Ultrasonically activated scissors may divide both vessels and cystic duct, with no need of further ligature, and possibly reduce the risk of thermal injuries. METHODS: A prospective nonrandomized clinical trial was started in 1999 to test harmonic shears (Ultracision, Ethicon Endo-Surgery, Cincinnati, OH, USA) in 461 consecutive patients undergoing LC in order to evaluate the theoretical benefits of ultrasonic dissection and the possible reduction in intraoperative bile duct injuries (BDIs) and postoperative complications. Patients were divided in two groups: in group 1 (HS; 331 patients) the operation was performed by Ultracision (including coagulation-division of cystic duct and artery); in group 2 (LOOP; 130 patients) the cystic duct, after coagulation-division by harmonic scissors, was further secured with an endo-loop. Both groups were further divided into two subgroups: expert and surgeon-in-training. The following categories of data were collected and analyzed: individual patient data, indication for laparoscopic cholecystectomy, surgical procedure data (associated procedures, intraoperative cholangiography, intraoperative complications, length of surgery, and conversion to open), and postoperative course data (postoperative morbidity, postoperative mortality, reinterventions, and postoperative hospital stay). Furthermore, biliary complications were analyzed as a single parameter comparing the incidence within groups and subgroups. Cumulative complications (intraoperative and postoperative) were also analyzed as a single parameter comparing their incidence in the series of each surgeon within the surgeon-in-training subgroup to the average results of the expert subgroup. Finally, length of surgery, postoperative complication rate, and length of postoperative hospital stay within subgroups were analyzed to evaluate the learning curve. RESULTS: Overall conversion rate was 0.87%. The mean operating time was 76.8 min (median, 70 min) in group 1 and 97.5 min (median 90 min) in group 2. BDI occurred in 1 case (0.32%) in the surgeon-in-training subgroup. Overall BDI rate was 0.22% (1/461). The overall incidence of postoperative bile leak was 2.7% (9 patients of subgroup 1 and 1 patient of subgroup 2). Clinical observation with spontaneous resolution occurred in 4 patients, and in 1 case the management consisted in an endoscopic biliary drainage; surgery was requested in the remaining cases. A laparoscopic approach was successfully attempted in all cases. Overall morbidity rate was 8.76% in group 1 and 13.84% in group 2. Rates of major complications, overall biliary complication, and postoperative bile leaks within the expert and surgeon-in-training subgroup differ significantly (p = 0.026, p = 0.03, and p = 0.049, respectively). There was 1 death (0.22%) due to sepsis that resulted from a small bowel injury by trocar insertion. Mean postoperative stay was 4.28 days for group 1 and 5.05 days for group 2. CONCLUSION: No significant difference was found in both patient groups regarding postoperative mortality and complications, biliary complications, and especially cystic duct leaks. A retrospective comparison of literature data showed that use of ultrasonic dissection during LC seems to reduce the risk of BDI. Nevertheless, a learning curve in the use of ultrasonic-activated devices is required: a significant differences in postoperative major complications and biliary complications between the expert and the surgeon-in-training subgroups was shown. Furthermore, ultrasonic scissors misuse may cause bowel injuries in patients with severe adhesions, and this could represent a possible limitation for surgical safety.

Adolescent↗
PubMed1991

Ultrasonic surgical aspirator for lung resection.

The ultrasonic surgical aspirator was originally developed for neurosurgical procedures and hepatic resections. Ultrasonic vibration at the tip of the instrument results in lysis of the parenchymal cells, leaving more resistant fibrous tissue such as blood vessels and bronchi intact and, thus, minimizing blood loss. We have studied the feasibility of applying the ultrasonic surgical aspirator for segmental and subsegmental lung resection for primary and metastatic neoplasms of the lung. Over the past 5 years, 27 patients underwent segmental or limited lung resection using the ultrasonic surgical aspirator. Except for prolonged air leak in 6 patients postoperatively, no other serious morbidity was noted. We observed several advantages: (1) the ultrasonic surgical aspirator dissects out the pulmonary vessels and bronchi, allowing the surgeon to perform segmental and subsegmental resections with minimal blood loss, (2) it permits lung-sparing operation for centrally located tumors that would otherwise have required lobectomy, and (3) it allows direct visualization of lung parenchyma during dissection, thus assuring grossly adequate margins.

Adolescent↗
PubMed1991

Microimplants of estradiol in the sexually dimorphic area of the hypothalamus activate ultrasonic vocal behavior in male Mongolian gerbils.

The hormonal control of ultrasonic vocal behavior in the male Mongolian gerbil was examined by comparing the behavioral effects of androgen with those of estrogen administered to the preoptic-anterior hypothalamic area (POA-AH) in castrates. By measuring radioactivity released from solid "floating" POA-AH microimplants (mean diameter, 141 microns) of testosterone (3H-T, mean weight, 880 ng) in Experiment 1, we found that the steroid had a concentration gradient which fell rapidly from the edge of the microimplant, suggesting restricted diffusion. Using floating microimplants in Experiment 2, we studied the effects of testosterone propionate (TP, 650 ng), estradiol-17 beta benzoate (EB, 439 ng), or cholesterol (C, 478 ng) on rates of a frequency modulated ultrasonic vocalization emitted during sexual interactions. The effects on the upsweep call were compared with those on sexual mounting. The upsweep rate remained significantly below precastration levels in C implanted males. EB reinstated upsweep calling within 5 days, 3 days earlier than TP microimplants. Mounting in EB implanted males was maintained at precastration levels, whereas TP implantation restored mounting to precastration levels only after 5 days. EB was effective in inducing ultrasonic vocalizations when placed in, or near, the sexually dimorphic area (SDA) in the medial preoptic area (POM). Our results indicate that brain mechanisms underlying both ultrasonic vocalizations and mounting are directly sensitive to estradiol (E2) in the male gerbil. We conclude that E2 affects mechanisms in the SDA associated with ultrasonic calling and suggest that T is likely to act via aromatization products in the brain.

Animals↗
PubMed1989

The emission and elicitation of mouse ultrasonic vocalizations: the effects of age, sex and gonadal status.

Subject' mice of varying gonadal status (castrate males; intact or neonatally gonadectomized females and males) were paired for 3-min with intact 'stimulus' females and ultrasonic vocalizations were monitored. Vocalization patterns from home cages differed from the test pairings. The results suggested that the age, experience and gonadal status of the subject influenced the vocalizations from the pair. As the source of ultrasonic calls from these vocally intact pairs could not be individually identified, the 'subjects' were paired with a range of ultrasonically silent (inferior laryngeal nerve-transected) stimulus animals. Vocalizations were detected from all combinations of animals. Gonadally intact females were most effective in eliciting ultrasonic vocalizations from the subjects and gonadally intact males were least effective. The responses of castrate males were lower than from intact males. Anesthetized adults of either sex elicited only poor vocalization responses from other adults. Ultrasonic calls have often previously been studied using vocally intact 'subject' and 'stimulus' animals: the present results confirm the difficulty of establishing who is who in such situations.

Aging↗
PubMed1992

Vomeronasal and/or olfactory mediation of ultrasonic calling and scent marking by female golden hamsters.

The role of the olfactory and vomeronasal systems in mediating odor-stimulated ultrasonic calling, flank marking, and vaginal marking by female hamsters was investigated by selective lesions of either system. Removal of the vomeronasal organ resulted in reduced frequencies of ultrasonic calling by estrous and nonestrous females in response to conspecific odors but it had no influence on either scent marking behavior during the same tests. When tested immediately after separation from a male, ultrasonic calling was not reduced by vomeronasal removal, indicating that such surgery does not cause deficits in calling ability and that the vomeronasal organ specifically mediates odor-stimulated calling. Zinc sulfate treatment of the olfactory mucosa led to reduction in the frequency of ultrasonic calling, flank marking, and vaginal marking in response to conspecific odors. Females' ability to discover buried food was also impaired by this treatment. Thus, the stimulation of both scent marking behaviors due to the perception of conspecific odors appears to be mediated primarily by the olfactory system, whereas stimulation of ultrasonic calling is mediated by both olfactory and vomeronasal systems.

Animals↗
PubMed2006

Ultrasonic endarterectomy for long superficial femoral artery atherosclerotic occlusive disease.

OBJECTIVE: To report the long term results of ultrasonic superficial femoral artery endarterectomy (USFAE). DESIGN: Retrospective study. PATIENTS AND METHODS: From January 1998 to June 2004 218 USFAE were performed in 202 selected patients (178 males, 192 procedures) with a median age of 65 years (46-87 years). Indications for operation were disabling intermittent claudication in 137 procedures (68%), rest pain in 24 procedures (12%), and limb salvage in 41 procedures (20%). The new medical technology of ultrasonic endarterectomy is based on the application of the mechanical vibrations in the range of low frequency ultrasound. The ultrasonic device consists of the ultrasonic generator, acoustic unit and the flexible wave concentrators with special working tips in the shape of a ring. Follow up consisted of clinical evaluation, ankle-brachial index measurements and duplex scanning. RESULTS: The mean follow-up time was 30.1 months. The mean length of the endarterectomised SFAs was 29 cm (range, 15-43 cm). The five year cumulative primary patency rate by means of life table analysis was 45.8 +/- 4.4% (SE). Percutaneous transluminal balloon angioplasty and surgical re-interventions were performed in thirty three and five patients respectively resulting in a primary assisted patency rate of 57.5 +/- 4.1%. The five year secondary patency rate was 65.6 +/- 3.8%. Limb salvage was achieved in 35 of the 41 patients with gangrene. CONCLUSIONS: The long term results of ultrasonic SFA endarterectomy suggest this is an effective technique.

Aged↗
PubMed2005

Antimicrobial activity of ultrasonic cleaners.

This study assessed the antimicrobial activity of two cleaning solutions and tap water after varying periods of use in one ultrasonic cleaner. Testing involved filling the cleaner's tank and a centred glass beaker with the same test solution. An aluminium foil strip test first determined that no significant differences in cavitational activity existed inside the beaker compared with outside. Standardized solutions of Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella choleraesuis were left at room temperature for 10 min. Aliquots were exposed to both cleaning solution and ultrasonic action. Unused test solution was removed from the tank, filter-sterilized, mixed with bacterial suspension and placed into a sterile beaker. Cleaning was allowed for 10 min. The beaker was removed and its contents examined. The tank was allowed to cool for 30 min and the process was repeated four times. The entire experimental set was repeated once. Exposure to test solution alone in all but one case produced reductions in bacterial numbers from initial >/=2 x 10(9) by 19.9-52.6%. Application of both chemical exposure and ultrasonic cleaning produced greater bacterial kill (46.4-99.7% reductions). However, kill became less effective on repeated use of a commercial cleaning solution. Reduction was highest when fresh ultrasonic cleaning solutions were used. In no case did complete sterilization occur. As well as removing adherent material, ultrasonic cleaning may also markedly reduce the number of viable organisms present.

Disinfection↗
PubMed2004

An improved automated ultrasonic NDE system by wavelet and neuron networks.

Despite of the widespread and increasing use of digitized signals, the ultrasonic testing community has not realized yet the full potential of the electronic processing. The performance of an ultrasonic flaw detection method is evaluated by the success of distinguishing the flaw echoes from those scattered by microstructures. So, de-noising of ultrasonic signals is extremely important as to correctly identify smaller defects, because the probability of detection usually decreases as the defect size decreases, while the probability of false call does increase. In this paper, the wavelet transform has been successfully experimented to suppress noise and to enhance flaw location from ultrasonic signal, with a good defect localization. The obtained result is then directed to an automatic Artificial Neuronal Networks classification and learning algorithm of defects from A-scan data. Since there is some uncertainty connected with the testing technique, the system needs a numerical modelling. So, knowing the technical characteristics of the transducer, we can preview which are the defects that experimental inspection should find. Indeed, the system performs simulation of the ultrasonic wave propagation in the material, and gives a very helpful tool to get information and physical phenomena understanding, which can help to a suitable prediction of the service life of the component.

Materials Testing↗
PubMed2005

Ultrasonic techniques for nondestructive testing of standing trees.

The aim of this study is to assess wood quality of standing trees with ultrasonic velocity methods. The ultrasonic techniques currently used are: scattering based techniques that use travel time and other wave parameters for measuring the elastic constants of wood, and ultrasonic tomographic imaging techniques which seek to provide a high resolution picture of the defect. Scattering based techniques were firstly used as nondestructive techniques with increment cores of 5 mm diameter. On these specimens measurements with bulk waves--longitudinal and shear were used to detect the influence of sylvicultural treatment (pruning) on wood quality and also to detect defects (slope of grain, wavy figures). High resolution imaging techniques were developed for imaging abnormalities induced by biological attacks of fungi or insects in standing trees. In this case, ultrasonic tomography refers to cross-sectional imaging of trees from data collected by illuminating the tree from different directions. Ultrasonic images were reconstructed from the time of flight. The images were reconstructed from 120 measurements in situ and through the bark with direct transmission technique, using 1 MHz transducers. The resolution is 5 cm.

Animals↗
PubMed2005

Ultrasonic pre-irradiation effect upon aqueous enzymatic oil extraction from almond and apricot seeds.

The present work evaluates the benefit of using ultrasonic pre-irradiation before extracting oil from almond and apricot seeds by aqueous enzymatic oil extraction (AEOE) process. The use of a commercial preparation which is a mixture of three proteases in AEOE gave 75% w/w oil yield from almonds at pH 4.0 in 18 h at 40 degrees C. The ultrasonic pre-irradiation at 70 W for 2 min increased the yield to 95%, w/w and reduced the extraction time to 6 h. The effect of ultrasonic pre-irradiation on meal morphology could be visually seen by scanning electron micrographs. It indicates development of of microfractures and disruption of cell walls in almond powder. With apricot, also, ultrasonic pre-irradiation also marginally increased the oil yield obtained by AEOE to 77% w/w and reduced the extraction time to 6 h. Thus, ultrasonic pre-irradiation step may reduce time required to extract oil from edible oils from plant sources and hence can improve through put in commercial oil production process.

Hydrogen-Ion Concentration↗
PubMed2006

Physiochemical properties of digested sewage sludge with ultrasonic treatment.

We investigated the dewaterability and physiochemical properties of digested sludge after treatment with ultrasonic energy for the purpose of reducing sludge. The study involved laboratory experimentation under varying test conditions of treatment time, volume of sludge and ultrasonic energy, which combined can be denoted as specific supplied energy (E(v)). Results of the experiments show that particle size (dp(50), dp(10), U) of the ultrasonically treated sludge decreases due to the separation of sludge flocs. Capillary suction times (CSTs) decrease significantly, while turbidity, VDSs/VS and SCODs/TCOD increase with ultrasonic treatment. From these results, it was found that the ultrasonic treatment specified by the supplied energy (E(v)) can not only improve dewaterability but also reduce the volume and mass and change the chemical properties of sludge.

Sewage↗