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PubMed1986

Correlation of the ultrasonic appearance of the ovaries in polycystic ovarian disease and the clinical, hormonal, and laparoscopic findings.

The ovarian ultrasonic appearance in 20 patients with polycystic ovarian disease was studied and correlated to the clinical, hormonal, and laparoscopic findings. Ultrasound studies showed that both ovaries were enlarged in 15 patients (15.46 +/- 2.5 cm3). Maximum ovarian surface area was 9.75 +/- 3.38 cm2. Three ultrasonic patterns were detected: (1) isoechoic, with no discernible cysts (four patients); (2) hypoechoic, with multiple small cysts of less than 1 cm (11 patients); (3) hypoechoic, with single cyst of greater than 1 cm (five patients). Ultrasonic estimation of ovarian size was superior to clinical assessment and equal to that of laparoscopic examination. Subtle differences existed between the ultrasonic appearance of the ovaries in hyperprolactinemic subgroups of polycystic ovarian disease compared to normoprolactinemic ones. However, no significant relationship was found between the ovarian size and any of the hormones studied. Obesity, amenorrhea, hirsutism, hyperprolactinemia, and elevated testosterone and dehydroepiandrosterone sulfate levels were more common in the group with enlarged ovaries, whereas oligomenorrhea, elevated luteinizing hormone/follicle-stimulating hormone ratio, and elevated androstenedione and estrone levels occurred more frequently in the group with normal-sized ovaries. The value of ultrasound studies in the management of polycystic ovarian disease is emphasized.

Adolescent↗

PubMed1994

Ultrasonic assessment of internal thoracic artery graft flow in the revascularized heart.

We investigated the clinical applicability of the transit-time ultrasound technique for quantitation of internal thoracic artery (ITA) graft flow in coronary artery bypass grafting. Intraoperative measurements of arterial and venous coronary graft flow were performed in 63 patients using an ultrasonic flowmeter. Native ITA blood flow was determined using a skeletonized segment of the ITA and a flexible perivascular flow probe. Simultaneous measures of ultrasonic blood flow from the proximal part of the ITA and free flow from the distal cut end of the ITA validated reliability. After coronary grafting, separate perivascular flow probes over the saphenous vein and ITA grafts were positioned to measure flows during cardiopulmonary bypass and immediately before the sternal closure. Mean native ITA flow was 7 +/- 0.8 mL/min and ITA graft flow was 35 +/- 4 mL/min, a fivefold increase after grafting to the coronary artery (p < 0.001). Mean saphenous vein graft blood flow of 38 +/- 4 mL/min was not significantly different from the mean ITA graft flow (p = 0.37). Coronary blood flow via saphenous vein and ITA conduits was unaffected by the cardiopulmonary bypass (p = 0.73). No complications were directly caused by the flow measurements. Flow impedance resulting from pedicle twist at the distal anastomosis was easily detected in 2 patients using the ultrasonic flowmeter. We conclude that ITA graft flow can be quantitated intraoperatively by the transit-time ultrasound technique. Ultrasonic assessment of ITA graft flow in the revascularized heart may be a useful means of detecting immediate coronary graft failure caused by technical errors.

Coronary Artery Bypass↗

PubMed1995

Comparison of optical, needle probe and ultrasonic techniques for the measurement of articular cartilage thickness.

Analysis of the mechanical properties of articular cartilage necessitates determination of thickness of the tested tissue. To evaluate the suitability of different methods for thickness measurements, the thickness of bovine and canine knee articular cartilage was determined with optical (stereomicroscopic), needle probe and ultrasonic techniques. The results obtained with the stereomicroscope and the needle probe showed high, linear correlations (r = 0.97, n = 80). The mean thickness obtained with the needle was slightly higher than the optical thickness (0.88 +/- 0.36 mm vs 0.85 +/- 0.34 mm, mean +/- S.D., n = 80, p < 0.01, matched-pairs Student t-test) or the ultrasonic thickness (0.93 +/- 0.42 mm vs 0.87 +/- 0.36 mm, n = 45, p < 0.05). The high scatter between optical and ultrasonic thickness, considered to be due to complex measurement geometry of canine knee articular cartilage, invalidated the use of the A-mode, 10 MHz-ultrasonic device for thickness measurements. Based on the results of uncertainty analysis it is concluded that optical and needle probe methods can be used interchangeably when determining shear modulus of articular cartilage with indentation tests. However, if high area-aspect ratios (indenter radius-to-cartilage thickness ratios) are used in the indentation measurements uncertainty in shear modulus may be markedly increased due to possible errors in the measurement of cartilage thickness.

Animals↗

PubMed1994

A comparison of reflection and transmission ultrasonic techniques for measurement of cancellous bone elasticity.

A reflection ultrasonic technique, which offers several advantages over transmission ultrasonic techniques, has been described for elastic property measurement of bone. Ultrasonic velocities from specimens of cancellous bone were compared using a reflection ultrasound technique and the more traditional transmission ultrasonic technique. The two techniques were found to yield velocities which were reasonably well correlated (r2 = 0.74). However, a statistical difference was found between the line of identity and the regression between transmission and reflection velocities (due to an offset in the intercept). In spite of differences in intercept between velocities measured by the two techniques, significant correlation was found between the two methods, suggesting that the reflection technique can measure wave velocities meaningful to bone elasticity.

Animals↗

PubMed1986

Prenatal ultrasonic diagnosis of anterior abdominal wall defects.

Nine cases of different types of anterior abdominal wall defects were diagnosed prenatally by ultrasound: gastroschisis (one case), omphalocele (five cases), exstrophy of the cloaca (one case) and the extreme form of prune belly syndrome (two cases). The ultrasonic features of gastroschisis and omphalocele are well recognized by most experienced sonographists. The ultrasonic prenatal diagnosis of exstrophy of the cloaca has not been reported previously and it is a very rare entity. The anterior abdominal wall defect is larger than in omphalocene and is located infraumbilically. Fetal ascites and a lumbosacral myelomeningocele are present as well. The extreme form of prune belly syndrome is associated with the absence of the abdominal wall musculature and marked dilatation of the urinary tract, presented ultrasonically as multiple large cysts occupying the distended fetal abdominal cavity. The differential diagnosis of these entities and guidelines for their correct prenatal ultrasonic diagnosis will be discussed.

Abdominal Muscles↗

PubMed1975

Segmental ultrasonic test for the study of cholecystodyskinesia.

Ten patients of ages 35 to 61 years with 'cholecystopathy' received an injection of 20 ml, 40% biligrafin. X-rays of the gall-bladder area were taken before and at certain intervals after the injection. This was followed by ultrasonic stimulation (applied using the impulse technique) for ten to twenty minutes at frequencies of 3 MHz, effective intensity of 1.4-2.8 W cm-2 and with paraffin oil as a contact agent. The dorsal segments were subjected to ultrasonic stimulation of weaker intensity but longer duration than the ventral segment. The gall-bladder shadow was analysed planimetrically, and an approximate volumetric calculation was attempted. The results show that the gall-bladder responds to segmental ultrasonic stimulation by both contraction and dilatation, presumably through a cutaneous visceral reflex arch, a qualitatively and quantitatively different response to that of egg yolk. Segmental ultrasonic stimulation of the gall-bladder seems to be a suitable complement to fatty meal treatment, particularly where this 'contra-indicated'. In addition it offers the possibility of differentiating between hyper and hypokinetic forms of gall-bladder dyskinesia. Finally, it was observed that a more marked effect on the gall-bladder can be produced by dorsal-segmental stimulation than by stimulation over the ventral points.

Adult↗

PubMed1976

Possibilities and limitations of ultrasonic diagnosis of space occupying lesions in internal medicine.

Possibilities and limitations of ultrasonic tumour diagnosis in internal medicine (thyroid gland, liver, pancreas, kidney, malignant lymphomas) are discussed on the basis of a five years experience with about 4,000 examinations a year. A real time and gray-scale technique is used. The accuracy of the presented ultrasonic findings is proven by comparative studies. Besides the well known advantages of ultrasonography the independence from contrast medias must be stressed in comparison to diagnostic radiology. The main limitations of ultrasonography are the impossibility of diagnosing tumours smaller than 1.5-2 cm and the absence of an ultrasonic pattern typical of malignancy. To establish a morphobiological diagnosis, ultrasonically guided fine needle biopsy has proved to be a reliable method.

Acute Disease↗

PubMed1989

Ultrasonic non-destructive measurements of cortical bone thickness in human cadaver femur.

The knowledge of the cortical bone thickness profile in human bone has a two-fold clinical significance: to study the stress occurring in a loaded bone structure to optimize the design of prostheses; and to predict the onset of advanced bone disease such as osteoporosis. In this study, the cortical bone thickness in three embalmed human cadaver femora were measured non-destructively using an ultrasonic technique. These thickness measurements were also made using a computed tomographic (CT) scanning method. Subsequently bones were sectioned and the actual bone thicknesses in the same regions were measured using a micrometer. The correlation coefficient between the actual thickness and the ultrasonically measured thickness was 0.95 and with the CT was 0.62. Thus, these results show that, under present experimental conditions, ultrasonic thickness measurements compare well with the micrometer actual thickness results. This technique, when fully developed, can be used as a non-destructive tool for quantitative cortical bone thickness measurements. Moreover, the ultrasonic technique does not use ionizing radiation.

Bone and Bones↗

PubMed1996

An ultrasonic-operated kinematic measurement system for assessment of stance balance in the clinic.

This study describes the application of a kinematic measurement system based on ultrasonic technology to enable the assessment of stance balance in the clinic. The system is composed of 1-8 ultrasonic transducer markers which transmit ultrasonic waves, and three ultrasonic receivers. The spatial position of each marker is monitored by calculation of the time interval between transmission and reception of the wave. Sway data from the waist of 44 healthy subjects and 15 hemiparetic patients were collected during quiet stance. The results distinguished between data collected with and without vision, between patients and controls, and between the two sides of the body. The findings were found to be valid and reliable in repeated measurements. RELEVANCE:--Assessment of stance balance in the clinic is a requisite for quantifying disability and measuring improvement in patients with postural control deficits. Due to high costs and complexity of operation, the use of prevailing equipment for these purposes is mainly confined to research facilities. This paper describes a unique kinematic measurement system whose low price and ease of operation make it feasible for clinical use.

Journal Article↗

PubMed1992

Dependence of ultrasonic attenuation of liver on pathologic fat and fibrosis: examination with experimental fatty liver and liver fibrosis models.

To clarify the effect of the pathological state of the liver on ultrasonic attenuation, we produced two experimental rabbit models. The influence of fat on ultrasonic attenuation was examined using a fatty liver model without liver fibrosis, and that of fibrosis on attenuation using a liver fibrosis model without fatty infiltration. Ultrasonic data were obtained in vivo directly from the liver, and an acoustic attenuation coefficient slope was obtained by the spectral difference method. Tissue components of the liver, namely the total lipid, hydroxyproline and water contents, were measured precisely by quantitative methods. We revealed that ultrasonic attenuation depends mainly on fatty infiltration of the liver and to a lesser extent on fibrosis, but not on the water content.

Adipose Tissue↗

PubMed1993

Effect of perfusion and blood content on ultrasonic backscattering of liver tissue.

The purpose of this study was to determine the effect of blood flow perfusion and red cell content on ultrasonic scattering by liver tissue. Data acquisition for ultrasonic tissue characterization (UTC) employing analysis of the backscattered echoes from the power spectrum was obtained from the same region of pig liver tissue under four conditions: 1) normal perfusion in situ, 2) ischemia in situ in the living pig, 3) ischemia in situ immediately postmortem, and 4) immediately after excision of the liver. Discriminant function analysis was used to evaluate differences in the two basic parameters from the normalized power spectrum: slope and intercept. Normal perfused liver had significantly higher intercept values and lower slope values than liver under the other three conditions. Excised liver showed the lowest intercept and highest slope values (p < 0.01). These experiments indicate that differences in perfusion produce significant differences in ultrasonic scattering by liver tissue (ischemia caused a 3 dB drop in intercept amplitude). Normal or ischemic in vivo and in vitro liver tissue is associated with different patterns of ultrasonic scattering, and scattering data under these various circumstances are not equivalent.

Animals↗

PubMed1986

Inhibition of shock-elicited ultrasonic vocalization by opioid peptides in the rat: a psychotropic effect.

Following three series of electric footshocks (10 shocks/day), one out of three rats in most cages were brought to emit ultrasonic vocalization for several minutes after a single shock. The characteristics of shock-elicited ultrasound were pure tone pulses of a frequency between 22 and 28 kHz, with duration longer than 300 msec. The same type of ultrasound is produced by subordinate male rats during agonistic behavior. The intracerebroventricular injection of beta-endorphin, dynorphin, methionine-enkephalin or leucine-enkephalin attenuated the shock-elicited ultrasonic vocalization. Psychotropic drugs such as diazepam and chlorpromazine also attenuated the shock-elicited ultrasonic vocalization. A test utilizing ultrasonic vocalization in rodents can provide useful data for studying the psychotropic properties of neuropeptides.

Animals↗

PubMed1993

Ultrasonic backscatter system for automated on-line endocardial boundary detection: evaluation by ultrafast computed tomography.

OBJECTIVES: The purpose of this study was to evaluate the accuracy of the recently developed echocardiographic on-line endocardial border detection system using ultrafast computed tomography, an independent and proved tomographic imaging modality. BACKGROUND: The automated system for on-line endocardial border detection identifies the blood-tissue interface by acoustic quantification of the ultrasonic backscatter signal. METHODS: Eighteen subjects were screened by conventional echocardiography and acoustic quantification. Ten of these, with high quality echocardiographic images, were also examined by ultrafast computed tomography. Comparable image planes at the midpapillary level were analyzed. Measurements of left ventricular cavity area were compared at end-diastole and end-systole and time course analyses of cavity area during the cardiac cycle were performed. RESULTS: There was good correlation between values for left ventricular end-diastolic area (r = 0.99), end-systolic area (r = 0.93) and fractional area change (r = 0.91) using the two methods. The on-line backscatter system underestimated end-diastolic area (p < 0.001), but the negative bias was small (-1.6 cm2) and the 95% confidence intervals were narrow (-3.6 cm2 to +0.4 cm2). In contrast, the backscatter system overestimated end-systolic area (p < 0.02); the positive bias for this variable was also small (+2.6 cm2) but the confidence intervals were relatively wide (+7.9 to -2.8 cm2). The negative bias of backscatter values for cavity area was fairly constant during diastole and early systole (range -5% to -10%), but during the second half of systole, backscatter values increased progressively relative to computed tomographic values. Real time values for fractional area change measured by the backscatter system were 13% smaller than those determined by ultrafast computed tomography (p < 0.001), with wide confidence intervals (+3% to -30%). Absolute peak rates of area change during systole and diastole were lower by 39% (p < 0.001) and 41% (p < 0.01), respectively, using the on-line ultrasonic backscatter system. Time course analyses revealed the errors to be consistent with cardiac cycle-dependent alterations in gain sensitivity of the ultrasonic backscatter system. CONCLUSIONS: The ultrasonic backscatter system is associated with cyclic cavity area measurement errors that need to be addressed if its early promise for on-line assessment of ventricular function is to be fulfilled. Incorporation of an electrocardiographically triggered time-varying gain control may improve accuracy for on-line analysis of ventricular performance.

Echocardiography↗

PubMed2005

Relationship between density and ultrasonic velocity in Brazilian tropical woods.

In this study, the effect of density on the velocity of an ultrasonic wave in wood is investigated. The aim of the present study was to analyze the influence of density on the longitudinal velocity of an ultrasonic wave, propagated in the longitudinal direction. Experiments were conducted on 5cm x 5cm x 5cm wood specimens selected from the following species: pinus caribea (Pinus caribea var. caribea), eucalyptus citriodora (Eucalyptus citriodora), eucalyptus grandis (Eucalyptus grandis), cupiúba (Goupia glabra) and jatobá (Hymenaea sp.). The relationship between density and velocity was analyzed in two different manners: between and within species. The results obtained between species indicated that ultrasonic velocity tends to increase with increasing density. The results obtained within species also showed an increasing trend in ultrasonic velocity as density increased, but the relationship was not as significant as it was for between species.

Brazil↗

PubMed2006

Comparison of central corneal thickness measurements with a new optical device and a standard ultrasonic pachymeter.

PURPOSE: To compare central corneal thickness (CCT) values obtained with ultrasonic pachymetry and a new optical method using partial coherence interferometry (PCI). SETTING: Department of Ophthalmology, Medical Health and Science Center, University of Debrecen, Debrecen, Hungary. METHODS: The study comprised 136 eyes of 70 patients whose spherical refractive error was not greater than +/-6.0 diopters (D) and whose keratometric astigmatism was not greater than 2.0 D. Central corneal thickness was measured 5 times with a new optical device (ACMaster, Zeiss) and with an ultrasonic pachymeter (AL-2000, Tomey). All measurements were obtained by the same investigator. RESULTS: Mean CCT was 531.2 microm +/- 3.9 (SD) with PCI and 547.8 +/- 36.0 microm with the ultrasonic device. The difference between groups was significant (P = .001). There was no difference between CCT values measured in right and left eyes (P = .55) with ultrasonography and PCI (P = .67). The coefficient variation was 0.73% for PCI and 6.5% for ultrasonography. Correlation between the CCT measurements with both devices was strong and statistically significant (Spearman correlation = .91, P = .001). CONCLUSIONS: Mean CCT values measured by the PCI method were significantly smaller than those measured by the ultrasonic device. Central corneal thickness measured with PCI is more reproducible and seems to be more reliable than that measured by ultrasonography.

Adult↗

PubMed2006

The accuracy of ultrasonic indentation in detecting simulated bone displacement: a comparison of three techniques.

PURPOSE: Palpation is used most commonly to assess tissue stiffness despite its well-known deficiencies. As an improvement, a mechanical technique known as ultrasonic indentation has been proposed. The purpose of this study was to compare the accuracy of 3 ultrasonic indentation techniques in quantifying bone displacement in a specially constructed tissue simulator. METHODS: Three ultrasonic indentation techniques were tested for their accuracy: a rigid, laboratory-based method (rigid), a less rigid system actuated by hand (assisted), and a totally free-hand system (handheld). Each indentation technique was applied on a tissue simulator, which consisted of a deformable phantom overlying a displaceable piston to simulate soft tissue overlying bone. Measures of piston (ie, bone) displacement obtained by each indentation technique were compared with a gold standard of piston displacement to determine the accuracy of each technique. Statistical tests were used to determine if differences between experimental and reference measures of piston displacement were significant. RESULTS: When indented, phantom deformation preceded piston displacement because of unequal stiffness between the two. The rigid and assisted indentation techniques showed the best accuracy for measuring simulated bone displacement. Differences in accuracy between the rigid and assisted techniques were insignificant. The accuracy of the handheld technique was significantly less than the rigid and assisted techniques. CONCLUSIONS: The clinical utility of assisted ultrasonic indentation should be explored given its accuracy and the excessive size, cost, and complexity of the rigid technique. The large error magnitude of the handheld technique may exclude it from clinical use now.

Equipment Design↗

PubMed2005

M-mode color Doppler ultrasonic imaging of vertical tongue movement during articulatory movement.

To observe and estimate the movement of the tongue, ultrasonic investigation is the most harmless real-time monitoring procedure for analyzing articulatory movements. Color Doppler ultrasonic imaging is special in that it can only sample a moving target, and it can indicate the velocity and direction of the target by color and brightness in real time. This study assessed and demonstrated the validity of M-mode color Doppler ultrasonic imaging to observe the movements of the tongue during syllable repetition tasks performed by normal subjects and dysarthric patients, those affected by amyotrophic lateral sclerosis, cerebellar ataxia, Parkinsonism, and polymyopathy. When the transducer was set below the jaw, upward movement was indicated by a blue signal and downward movement was indicated by a red one on the screen of the ultrasound machine. We also measured the velocity of the tongue by contrast scale classified by 15 degrees. Thus, we could observe vertical tongue movement by a color-coded pattern after quantitative analysis. The Doppler signal patterns of normal subjects were verified by simultaneous video x-ray fluorography recordings. The findings for dysarthric patients corresponded well with previously reported features analyzed by other methods. Therefore, color Doppler ultrasonic imaging of the tongue is a useful procedure to researchers for clinical speech and voice studies.

Dysarthria↗

PubMed2004

Three-dimensional reconstruction of biological objects' internal structure heterogeneity from the set of ultrasonic tomograms.

The paper presents the method of the three-dimensional reconstruction of biological objects' internal structure heterogeneity based on the ultrasonic examination of a woman's breast biopsy phantom. The phantom is made of quasi-homogeneous dense gel in which drops of lesions, characterized by fixed sizes and two different acoustic impedances, were dipped at random. For the purpose of this research a special measurement setup was elaborated, enabling a non-invasive in vitro imaging of biological objects' internal structure in cross-sections for fixed levels, by means of ultrasound transmission tomography (UTT) using the parallel-ray projection geometry of scanning. The two-dimensional images of the local values of ultrasonic wave's propagation velocity in the phantom's internal structure (ultrasonic tomograms) were reconstructed for fixed levels (by using the convolution and back-projection algorithm) from the measurements of average values of ultrasonic signals' runtime propagated from many directions around the object dipped in water. Analyzing the values of particular pixels and using an appropriate image processing technique, in effect the three-dimensional image of heterogeneity boundaries in the examined phantom's internal structure was computer-reconstructed. The obtained results are compatible with the specification provided by the phantom's producer in terms of sizes and acoustic parameters of lesions, which can simulate pathological changes and of the gel imitating the healthy tissue. It means that the method presented, after an appropriate modification and development of the measurement setup with an aim to accelerate the object scanning process and thus provide an opportunity for non-invasive in vivo examinations, could be applied for detecting and diagnosing tumors in women's breasts.

Breast Neoplasms↗