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Diagnostic ultrasound was used in 103 patients with a clinically suspected fracture of the scaphoid bone in order to achieve an early diagnosis. There were 48 women and 55 men aged 10–75 years (mean 31.4 years) tested with ultrasound. Of the patients, 72 were tested within 3 days after injury the remainder between 4 and 42 days. Fracture was confirmed radiologically in 27. We found that the ultrasound test, applied with a frequency of 1 MHz and intensity of 0.5 W/cm2 and2.0 W/cm2 for 30s, had a sensitivity of 37 per cent and a specificity of 61 per cent. We thus conclude that ultrasound is not suitable for early diagnosis of scaphoid fracture.

During the manufacture of silicoferrochromium, fume is collected in electrostatic filters. The main reason is to prevent environmental pollution. A review of the literature shows that researchers have been conducted in order to investigate the economical usability of this fume for industrial purposes. Silicoferrochromium fume containing 85.5% SiO[sub 2] was investigated to determine whether it could be used as an admixture in concrete to increase its strength. The fume was added at the dosage rates of 0--5% by weight of cement, and a number of test specimens were prepared from this concrete mixture. The unit weight, ultrasound test, hardness, compressive strength of the concrete specimens were determined. The initial and final time of setting values of the mortar specimens were measured. The test results indicated that the properties of the concrete changed considerably with the addition of the silicoferrochromium fume. The compressive strength of the concrete was observed to be maximum at 2% fume content.

This paper aims to describe the macroscopic aspects of disease and radiological findings related to spina bifida in a newborn cat. A female cat was seen in labor at a veterinary clinic in Teresina-PI. By performing the ultrasound test it was possible detect the presence of three fetuses aged approximately 62 days and decreased heart rate. The patient underwent surgery immediately to cesarean section with ovariohysterectomy. One of the newborn cat showed changes consistent with spina bifida. The owner opted for the newborn cat euthanasia because is not known effective treatment for the case. There are insufficient researchs on the embryonic development aimed at prevention and treatment of these anomalies. These studies are necessary to ensure a good prognosis for patients.

Measurements of acoustic exposure made in water and then derated to account for the attenuation of tissue can be distorted by nonlinear effects. We have evaluated numerical indicators of such distortion in diagnostic ultrasound fields. We evaluate the indicators of the degree of nonlinearity in diagnostic ultrasound fields that could be used to guarantee `quasi-linearity' or to correct measurements made under nonlinear conditions. A new indicator, ?i, is introduced which can be calculated using measurements currently being made in ultrasound test labs.

A recent survey on ultrasound tissue equivalent test objects carried out by the Institute of Physical Sciences in Medicine clearly shows these objects to have limited useful lifetimes with deterioration setting in within 1 year of purchase.

Rod-shaped reflectors such as those used in the AIUM test object resonate at medical ultrasound frequencies, producing artifacts posterior to the reflector. Rods of various diameters and materials were examined to determine their resonant properties, and the effect of the Plexiglas scanning surface of the enclosure on image quality was studied. A theory predicting the resonant frequencies of rods is proposed, and methods of eliminating resonance artifacts are discussed.

A phantom consisting of a gel closely resembling human liver on B-mode scanning, and containing a rounded zone of decreased echogenicity, was used to create a series of B-mode ultrasonic images containing simulated "lesions" in random locations on the final recorded image. A homogeneous gel phantom was used to create a series of blank images. Images were recorded in three display formats: conventional white on black background, conventional black on white background, and black on a white background with luminance normalized to that of the conventional white on black image. Six subjects were presented with a randomized series of scans in the 3 display formats, and receiver operating characteristic analysis was used to assess the effect of display format on low-contrast detectability. Detectability of low-contrast "lesions" was lower in a high contrast image with black on white background compared to the medium contrast image in white on black format. Detectability with the black on white format having normalized luminance was generally intermediate between that observed for the two conventional formats.

Ethylene glycol-water mixtures have been found suitable for use in ultrasound test objects. A plot of the required percentage of ethylene glycol with room temperature for an acoustic velocity of 1540 m/sec is presented to aid the clinical user. The velocity measurements performed are shown to be dominated by near-field transient diffraction effects. A 30 percent ethylene glycol-water mixture has been found to have a constant acoustic velocity of 1638 +/- 3.5 m/sec over a wide temperature range (15.6 degrees C-38.4 degrees C). This mixture is suitable for a test object velocity standard. Proper use of the A.I.U.M. 100-mm test object is discussed.

The paper describes the details of an ultrasound test for carpal tunnel syndrome and compares the results of this with E.M.G. studies in a series of 19 patients. The equipment used was a standard therapeutic ultrasound unit and the tests were performed by a physiotherapist. The results were encouraging, with a 90% correlation with E.M.G. results.

A device (1) for ultrasound tests, comprising one or more transducers (4) for generating ultrasound beams with different powers and/or frequencies to be projected in direction of a plurality of targets (11), guaranteeing the separate control of the temperature both of the targets and of the transducers and it allows performing several tests contemporarily, by optimizing the functionality and the efficiency of the device, at the same time by guaranteeing results comparable therebetween for each test, and to this purpose it comprises: a first supporting structure (3) having at least a closed chamber (7; 23) receiving the body of said one or more transducers (4) and it is isolated from a propagation liquid medium, by leaving exposed each respective vibrating surface in contact with said liquid medium at a prefixed distance from the respective targets (11), the closed chamber containing a thermorefrigerating fluid in contact with the body of said one or more transducers; a second supporting structure (10) for said targets (11); means for refrigerating, through said thermorefrigerating fluid, the body of said one or more transducers (4); and means for keeping the liquid medium, which dampens said targets (11), at a predetermined temperature.