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A practical method for analyzing the biological effects of nontherapeutic ultrasound was applied to the data of 21 different principal investigators. The data were compiled so that individual investigators could develop tentative guidelines of their own regarding the hazards of diagnostic ultrasound in human beings. One set of guidelines developed suggested that exposures of minimal hazard lie below a log/log line connecting 100 ?s of 100 W/cm 2 ultrasound with 200 s of 100 mW/cm 2 ultrasound. An ultrasonic intensity of 100 mW/cm 2 or less was of little or no hazard for at least 10 000 s. These guidelines applied to both continuous- and pulsed-wave ultrasound doses that were described by average intensity multiplied by total exposure time. The proposed schedule was valid for 0.5-15 MHz and for all anatomic sites except the eyes.

Isolated dextrocardia or isolated levocardia almost invariably indicates the presence of a complex cardiac anomaly. An accurate anatomic diagnosis in patients with these malformations requires knowledge of the atrial position, the relative position of the ventricles (atrioventricular concordancy or discordancy) and the presence or absence of a ventricular septum. Fifteen patients were studied to demonstrate that diagnostic ultrasound, in conjunction with the plain chest roentgenogram, provides a noninvasive method for accurately assessing atrioventricular relations and arrangement of the great vessels, in the presence of isolated discordancy of the cardiac apex. The patients studied were aged 10 months to 17 years; seven had isolated dextrocardia, five had situs inversus totalis, two had isolated levocardia and one had levocardia with abdominal heterotaxy. Thirteen of the 15 patients evaluated by echocardiography underwent cardiac catheterization and angiography. The correct diagnosis was made from the echograms and plain chest roentgenograms alone in 11 of the 13 patients. We conclude that with echocardiography and the knowledge of atrial situs, it is possible to define accurately important anatomic relations before cardiac catheterization in patients with cardiac malposition.

Because diagnostic ultrasound is becoming widely recognized as a valuable diagnostic aid, its potential for producing toxicity must be considered. The current modes of usage are considered with regard to their dosage parameters and to the physical and biological effects of such dosages. The reported bio-effects involved in future applications are briefly presented and the necessity for a proper epidemiological survey is stressed.

Two cases of anterolateral ventricular aneurysm are presented; results of pre- and postoperative echocardiography were shown to correlate well with other diagnostic methods in demonstrating the lesion. Diagnostic ultrasound is a potentially valuable technique in the management of patients with ventricular aneurysm.

This paper describes techniques employing diagnostic ultrasound for monitoring various physiological parameters within the head and neck during speech production. The theoretical principles underlying these techniques are discussed together with basic instrumentation systems that have direct application to studies in speech physiology. Examples of A-scope measurement of pharyngeal wall depth, B-scans of the trachea, time-motion displays of the moving lateral pharyngeal wall, and Doppler monitoring of vocal-fold velocity are included. It is concluded that diagnostic ultrasound can be a useful tool in speech research.

The use of diagnostic ultrasound in the evaluation of suspected cases of molar pregnancy is described and other accepted diagnostic procedures in this disorder, i.e., amniography and pelvic angiography, are reviewed. The possible risks of these procedures are considered. Wider use of ultrasound might well serve to reduce the morbidity and mortality of molar pregnancy, as well as other associated conditions of early pregnancy.

The results of ultrasonic findings of patients are discussed who, after a clinical histological and X-ray exanimation, revealed a tumor in the region of the paranasal sinus. Ultrasound diagnostic was

In recent years increasing interest has developed in the use of diagnostic ultrasound in the investigation of lesions of the urinary tract. (Damascelli, Lattuada, Musumeci and Severini, 1968; Holmes, Wright, Meyer, Posatony and Howry, 1965; Holmes, 1966; 1967; Ostrum, Goldberg and Isard, 1967; Howry, 1965; Goldberg, Ostrum and Isard, 1968; West, 1967; Leopold, 1970; Schreck and Holmes, 1970). The present paper records our experience with diagnostic ultrasound in the investigation of the urinary tract with particular reference to space-occupying lesions. Initially, a number of patients without urinary tract lesions were scanned to standardize the technique of examination and to establish the ultrasonic appearances of the normal kidney and bladder. Subsequently a study was made of a series of 40 patients with a space-occupying lesion associated with the upper urinary tract, and a further 17 patients with a bladder tumour, 16 of which ultimately proved to be malignant. In addition, with reference to the diff...

After the technical data for our equipment were determined investigations were made for the chemical determination of diagnostic ultrasound intensities (Kretz pulse-echo equipment, series 7000, transd

Diagnostic ultrasound was used to record the movement of the anterior and posterior heart walls in 23 patients with proven pericardial effusion. Fifteen of these patients demonstrated heart-wall motion that could not be distinguished from the normal pattern. Two patients with acute cardiac tamponade exhibited markedly reduced cardiac motion. The ultrasoundcardiograms obtained from the remaining six patients indicated posterior displacement of the entire heart during systole. The extent of this cardiac displacement varied. Five of the six patients with excessive cardiac motion had malignant pericardial effusion, and four of the six had clinical evidence of cardiac tamponade. The two patients with the most marked excursions exhibited electrical alternation. The results of this study substantiate the theory that excessive cardiac motion may occur in some patients with pericardial effusion. Objective evidence is also provided in support of the positional etiology of electrical alternation associated with pericardial effusion. An attempt is made to identify some of the factors responsible for the observed abnormal cardiac motion, and some speculation is offered as to what role rotation might play in the cardiac displacement. This study also serves as an example of the type of cardiovascular investigation that can be performed with diagnostic ultrasound.

Diagnostic ultrasound provides the radiation therapist a very practical method of acquiring anatomical information for developing optimized radiation therapy plans. With ultrasound it is possible to record simultaneously the contour of the patient and the location and depth of tumors and normal structures. This information can easily be incorporated into current methods of computerized treatment planning. Ultrasound examination also assists in the accurate placement of treatment ports on the body surface, and allows adjustment of field size as tumors respond to treatment. It is predicted that diagnostic ultrasound examination will become a standard method of obtaining anatomical information for radiation therapy planning in all modern radiation treatment facilities.

The effect of diagnostic pulsed and continuous-wave ultrasound on maternal and fetal chromosomes was studied in patients admitted for hysterotomy for termination of pregnancy. Of the 35 patients who were insonated, 12 were exposed to pulsed ultrasound, 12 to continuous-wave ultrasound from a fetal-heart detector, and 11 to continuous wave ultrasound from a fetal-heart monitor. There was no increase in the number of chromosome aberrations in blood cultures from the mothers and fetuses who were insonated when compared with 11 mothers and fetuses who were not insonated.

Ultrasound examinations were carried out on 1114 apparently normal pregnant women cared for in three different centres, at various stages of pregnancy and with differing ultrasonic frequencies throughout. The incidence of fetal abnormality in the group was 2·7%. Neither the time in gestation of the first examination nor the number of examinations seemed to increase the risk of fetal abnormality.

The ultrasonic tissue visualization technique by means of the reflection method (Ultrasonotomography, Echography) has been utilized effectively for clinical diagnoses throughout the entire world. It has various kinds of advantages, and is also highly valued among many techniques in the application of diagnostic ultrasound. According to this trend, ultrasonotomography has been accepted as a new, routine, diagnostic tool, particularly in the fields of internal medicine, neurology, obstetrics and others. At the same time, this method has been discussed in its practical evaluation and limitation in comparison with other usual tissue visualization techniques such as X-ray, Scintigraphy and thermography. In this paper, the outline of the present state of diagnostic application of ultrasonotomography which has been carried out at the Research Center, as well as future prognosis, will be described from a clinical point of view.

Diagnostic ultrasound—a simple, noninvasive, non-traumatic, and apparently harmless technique—can potentially be used to screen all antenatal patients. Serial measurements of the fetal biparietal diameter is the most precise means of determining the fetal growth rate, and should be employed in high risk patients with complications or a poor obstetric history. Newer more dynamic tests such as assessing fetal urinary production may become useful in determining the optimal time for delivery once fetal growth retardation has been established.

Diagnostic ultrasound offers a new dimension in pregnancy evaluation heretofore unaccomplished by other methods, specifically in the area of fetal and placental develpoment and estimation of fetal size and maturity. Ultrasound offers a new and accurate method of placental localization eliminating exposure of the infant and mother to x‐ray irradiation. By the use of serial examinations from 1 to 3 days apart, the diagnosis of fetal death in utero can be made usually within one week. The early diagnosis of hydatidiform mole is now possible before the tumor products are expelled, thereby allowing for early evacuation of the tumor before the develpoment of serious toxic effects.

B-scan ultrasound can be a useful adjunct in the accurate placement of radiation therapy treatment ports in selected cases. In addition to providing information of value in the determination of field size and shape, the display of a lesion’s contour in cross section can be of use in the selection of multiple ports for optimal distribution of radiation. In addition, the rate of regression of a neoplasm during and after therapy may be documented.The technique, however, is limited by the horizontal resolution of the transducer, the presence of good acoustic interfaces at the tumor margin, and the blocking effect of gas within superimposed hollow viscera. Therefore, in many instances little useful information is obtained. However, because pulsed diagnostic ultrasound is innocuous,6 painless, and easily applied, its continued application and development is justified.

The basic principles of diagnostic ultrasound or sonar are given, together with the special technique required for scanning newborn infants and small children for kidney abnormalities. Illustrative examples of the potential of this procedure, both in diagnosis and in monitoring changes include a normal neonatal and preadolescent kidney, unilateral renal agenesis, duplex kidney, renal cyst, polycystic disease, nephroblastoma, and examples of mild and severe hydronephrosis.

Reflected ultrasound offers the clinician another diagnostic aid in the evaluation of patients with possible pericardial effusion. With its ability to detect interfaces between liquid and solid, this ultrasound technic makes it possible to demonstrate pericardial fluid both anterior and posterior to the heart. As with almost all diagnostic procedures, there are some limitations and potential difficulties. Sound waves travel poorly through air; therefore, the hyperinflated lung tissue associated with pulmonary emphysema seriously interferes with recording ultrasound echoes from the heart. In addition, although few in number, both false positive and false negative results have been obtained. Despite these problems, the clinical experience with this technic thus far has been very good. With a little experience the accuracy and reliability of this procedure is as good as, if not better than, any of the currently used radiographic methods of diagnosing pericardial effusion. Furthermore, the simplicity and safety of the commercially available ultrasound equipment reduce the examination to a simple bedside procedure that can be done in a matter of minutes. Thus, diagnostic ultrasound provides a quick, safe and fairly reliable method of detecting or excluding pericardial effusion.

Summary Ultrasound has proved to be a useful and practical additional tool in the routine examination of patients with renal masses or unilateral absence of renal function. In our hands it has been 87% accurate and by combining it with cyst puncture, we have avoided arteriography, general anaesthesia and surgical exploration in the majority of our cases with cystic lesions. We feel that it has no place as an isolated investigation for an instant and infallible diagnosis, but must be followed by a further diagnostic procedure whether it be a cyst puncture, arteriogram or a surgical exploration.

In this study the diagnostic value of ultrasound scanning of the thyroid is evaluated. Eighty-six patients with various thyroid disorders and 5 normal persons were investigated. In all patients and normal persons a 99mTc or 131I scintigram and an ultrasonic tomogram of the thyroid were made. Thyroid function also was assessed by a number of other laboratory methods. In 30 patients surgically removed thyroid specimens were examined pathologically. In addition to palpation and the scintigram, the ultrasonic tomogram gave good information about the size of the thyroid lobes and of thyroid nodules. Differentiation between a solid thyroid tumor and a cystic lesion was possible with this method. The value of diagnostic ultrasound in clinical thyroid investigation is discussed and several indications for its use are mentioned.

Ultrasound scanning can be a valuable aid in radiation treatment planning. It provides an easy and accurate method of obtaining body outlines and cross-sections of the treatment fields. In many cases, ultrasound scanning can delineate the borders of a soft tissue tumor which cannot easily be delineated by other methods. Thus, the changes during and following irradiation therapy can be followed.Certain limitations in the technique of obtaining cross-sections, that must be pointed out, are the presence of good acoustic interfaces at the tumor margin, the blocking effect of gas filled structures and bone, and the presence of skin incisions. However, in all cases an accurate body outline can be obtained.It should also be pointed out that pulsed diagnostic ultrasound is painless, innocuous to underlying tissues, and easily applied; thus, ultrasound procedures may be repeated as often as needed.

A retrospective study on abnormalities of the renal tract as referred to the Department of Diagnostic Ultrasound, United Bristol Hospitals, over a period of two years is reported. The physical principles and methods of ultrasonic scanning are briefly outlined. The results of 42 scans are analysed. No clinical details were available to the radiologists who assessed the scans, and all means of patient identification were removed from the scans. By combining the best of two interpretations an accuracy of diagnosis of over 80 per cent was achieved. Possible sources of error are discussed as are the previous applications of ultrasound to the investigation of the renal tract. Three cases with marked dilatation of the upper urinary tract are described in detail. The relationship of signs at ultrasound renography to clinical pathology is reported. Useful applications of the method occur in pregnancy, the poorly functioning kidney, polycystic disease and in the differentiation between solid and cystic spa...

With the extensive and ever‐increasing use of ultrasound in clinical medicine and the development of progressively more sophisticated systems of tissue visualization, the importance and urgency of specifying the safety standards and the possible hazards of over‐exposure to adult and embryonic tissues cannot be overemphasized. The implications of the results of several pertinent interaction studies and epidemiological surveys to the problem of realistic risk assessment are discussed.

One of the limiting factors in the external beam abdominal irradiation is renal tolerance. Hence the exact localization of the kidneys either prior to or during the course of irradiation therapy is necessary. Moreover, during irradiation of pathologically involved kidneys (lymphoma, leukaemia, secondary kidney involvement from solid tumour and in bilateral Wilms' tumour) localization of the kidney is essential for proper treatment. Previous techniques have involved the use of excretion urograms and isotope scans (Covington and Buzzi, 1972) and have been rather inaccurate since it is difficult to define the precise depth of the kidneys in relation to the skin. Others have recommended the application of diagnostic ultrasound to radiotherapy planning (Eule, Bockenstedt, and Salzman, 1973; Smith and Holm, 1970) but have not described in detail its application to the localization of the kidneys. Ultrasonographic localization, which prevents unaffected parts of the genito-urinary tract from being irradiated, is...

A diagnostic ultrasound system generates an echogram of patient contour, tumour volume and other organs. A special attachment to the scanner arm and a split table allows one to draw the complete contours. The echogram is transmitted into one of two storage scan converters and is also displayed on the video screen for immediate visual verification. The echogram is analysed by an on-line dedicated computer and the contour, tumour volume and neighbouring artifacts are identified, digitized and stored in the second scan converter, and are also displayed on a video monitor superimposed on the echogram. Radiation parameters are chosen and the resulting dose distribution is computed by a truncated external-beam program. The isodose curves are stored in the second scan converter and displayed on the video monitor superimposed on the echogram.

Compiled and edited by a nuclear radiologist who also uses diagnostic ultrasound, this book is intended to bring diagnostic ultrasound to the attention of practicing physicians. It is anticipated that conditions such as tumor masses and others will now be investigated by this new diagnostic modality. Some of the more common applications of diagnostic ultrasound such as detection of pericardial fluid, differentiation of renal masses, and mid-line echo encephalography are dealt with by a combined nuclear radiology and ultrasound approach. It is the authors' belief that the dual diagnostic approach improves the results as compared to either method alone. These points are illustrated with nuclear images and ultrasonograms; the latter are of poor quality. The editor's goals might best be satisfied by those portions of the book which deal with scanning in upper abdominal disease, the determination of fetal head size, and placental localization. Considerable expertise is evident in

In his introduction to this book, Arthur A. Keeney, MD, points with justifiable pride to the international cooperation exhibited in its preparation. R. Goldberg, MD, and L. Sarin, MB, have chosen as their collaborators some of the foremost investigators from around the world who are working with ultrasound for evaluation of ocular structures. The resulting monograph is the first in this field to systematically deal with the history, basic principles, techniques, problems, and clinical utility of ultrasound with specific application to the eye. The book is organized into 11 chapters, two appendices, and an extensive bibliography that provides a natural transition from history and basic physics to clinical techniques and problems of diagnostic ultrasound. Each aspect of current clinical investigation is covered although not all are treated extensively. The writing is concise and well edited with little extraneous and redundant material. In general, the illustrations are excellent although the photographs