Is an excretory urogram mandatory in patients with small to medium-sized renal and ureteric stones treated by extra corporeal shock wave lithotripsy?

BACKGROUND

An intravenous urogram (IVU) has traditionally been considered mandatory before treating renal and ureteric stones by extracorporeal shock wave lithotripsy (ESWL). This study was designed to see whether there is a difference in complications and the need for ancillary procedures in patients managed by ESWL for renal and ureteric calculi, according to preoperative imaging technique.

METHODS

This retrospective study compared 133 patients undergoing ESWL from January 2001 to July 2002. Patients were divided into three groups according to the preoperative imaging technique used: i) IVU; ii) non-contrast enhanced helical computed tomography (UHCT); and iii) ultrasound (US) + X-ray kidney, ureter and bladder (KUB). The groups were matched in terms of age and gender, as well as location, side and size of stones.

RESULTS

There was no statistically significantly difference for number of ESWL sessions, number of shock waves and use of ancillary procedures between the three groups. The stone-free rate was 98% for the IVU and UHCT groups, and 97% for the US + X-ray KUB group.

CONCLUSIONS

The complication rate and need for ancillary procedures was comparable across the three groups. Patients imaged by UHCT or US + X-ray KUB prior to ESWL for uncomplicated renal and ureteric stones do not require IVU.

The potential for thermal damage posed by microbubble ultrasound contrast agents

The development of coated microbubble ultrasound contrast agents for use in imaging applications and as carriers in drug and gene delivery applications has intensified the need for a clear understanding of their behaviour and potential bioeffects. Previous studies have focused on the risks posed by unencapsulated bubbles as representing the "worst case scenario". They have concluded that the risk of thermal damage should be minimal provided the threshold for inertial cavitation is not exceeded. However, these treatments have ignored the heating effects due to viscous dissipation in the coatings of contrast agent particles. Simulations indicate that the temperature rise due to this process may be sufficient to generate harmful bioeffects even under conventionally "safe" insonation conditions. The implications of these findings and strategies for addressing the risks posed by contrast agents are discussed.

Threshold estimates and superthreshold behavior of ultrasound-induced lung hemorrhage in adult rats: role of pulse duration

The study objective was to estimate the pressure threshold (ED(05), effective dose, or in situ peak rarefactional pressure associated with 5% probability of lesions) of ultrasound (US)-induced lung hemorrhage as a function of pulse duration (PD) in adult rats. A total of 220 10- to 11-week-old 250-g female Sprague-Dawley rats (Harlan) were randomly divided into 20 ultrasonic exposure groups (10 rats/group) and one sham group (20 rats). The 20 ultrasonic exposure groups (2.8-MHz; 10-s exposure duration; 1-kHz PRF; -6-dB pulse-echo focal beam width of 470 microm) were divided into four PD groups (1.3, 4.4, 8.2 and 11.6 micros) and, for each PD group, there were five in situ peak rarefactional pressures (range between 4 and 9 MPa). Rats were weighed, anesthetized, depilated, exposed, and euthanized under anesthesia. The left lung was removed and scored for the occurrence of hemorrhage. If hemorrhage was present, the lesion surface area and depth were measured. Individuals involved in animal handling, exposure and lesion scoring were "blinded" to the exposure conditions. Logistic regression analysis was used to examine the dependence of the lesion occurrences, and Gaussian tobit regression analysis was used to examine the dependence of the lesion surface areas and depths on in situ peak rarefactional pressure and PD. Threshold results are reported in terms of ED(05). For PDs of 1.3, 4.4, 8.2 and 11.6 micros, respectively, lesion occurrence ED(05)s were 3.1, 2.8, 2.3 and 2.0 MPa with standard errors around 0.6 MPa. Lesion size ED(05)s showed similar values. A mechanical index (MI) of 1.9, the US Food and Drug Administration (FDA) regulatory limit of diagnostic US equipment, is equivalent to the adult rat's in situ peak rarefactional pressure of 4.0 MPa. PDs of 8.2 and 11.6 micros had ED(05)s more than 2 standard errors below 4.0 MPa, indicating that the ED(05)s of these two PDs are statistically significantly different from 4.0 MPa. The ED(05) threshold levels for a PD of 1.3 micros are consistent with previous US-induced lung hemorrhage studies. As the PD increases, the ED(05) levels decrease, suggesting greater likelihood of lung damage as the PD increases. All of the ED(05)s are less than the FDA limit.

Side effects and complications of sonohysterosalpingography

OBJECTIVE

To evaluate the side effects and complications of, difficulties with, and possible solutions to the problems associated with sonohysterosalpingography.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

One thousand, one hundred fifty-three patients who underwent sonohysterosalpingography to investigate abnormal uterine bleeding, infertility, thick endometrium at transvaginal ultrasonography, müllerian abnormalities, or the Asherman syndrome.

MAIN OUTCOME MEASURE(S)

Side effects and complications of and difficulties related to the procedure. Tolerance was assessed by using a pain-rating scale.

RESULT(S)

Ninety-three percent (1,074 of 1,153) procedures were performed correctly. Investigation was not completed in 79 (7%) women; a second attempt was successful in 60 of these patients. Side effects, such as moderate or severe pelvic pain, vasovagal symptoms, nausea, and vomiting, occurred in 102 (8.8%) women. Such complications as fever and peritonitis occurred in 0.95% of patients.

CONCLUSION(S)

Sonohysterosalpingography is a simple, safe, and well-tolerated technique that has a low rate of side effects and rare complications.

Live scanning at ultrasound scientific conferences and the need for prudent policy

The practice of using live models to demonstrate ultrasonographic imaging equipment at scientific meetings has gained popularity in recent years. However, different medical conferences organisers take different positions, possibly due to differences in interpretation of the safety issue and their definition of medically relevant use of diagnostic ultrasound (US). Some offer little, or no, restriction and other US societies have produced policy that is subject to various interpretations. For example, some justify the practice of scanning live models on the basis of an assumed "educational" benefit, but this is virtually impossible to measure in an objective sense. One issue that seems to have largely universal agreement is that nonmedical use of diagnostic US should be discouraged. The AIUM has published a statement that this is "contrary to responsible medical practice." However, the definition of "nonmedical" application is somewhat less certain. The scanning of live models to display equipment on exhibit areas may be considered "nonmedical." In fact, the BMUS has published guidelines with quite restrictive output limits to be applied for various "nondiagnostic" purposes. Although this safety issue remains debatable, the ASUM maintains a conservative unambiguous policy that prohibits scanning of live models in the exhibition area at scientific meetings. Issues such as biosafety, ethics and medicolegal implications require careful consideration by US organizations and professional conference organisers.

Influence of contrast ultrasonography with perflutren lipid microspheres on microvessel injury

Microbubbles have been reported to enhance ultrasound (US)-related side effects in animal systems. The present study investigated the influence of contrast ultrasonography (US) with perflutren lipid microspheres, a recently developed second-generation contrast agent, on microvessels. Rat mesentery was exposed to 1.8-MHz pulsed US with intravenous injection of perflutren (0.1 or 1.0 ml/kg) or Levovist (300 mg/kg), and the microvessel bleeding and endothelial cell injury was examined. Impaired endothelial cells were identified by the fluorescence of propidium iodide. Microvessel bleeding was examined also in the rat myocardium. The interaction between 0.1 ml/kg of perflutren and US exposure did not cause microvessel bleeding, and did not increase endothelial cell injury compared with the sham operation, unless frequent, strong US exposure occurred. When the dose was increased to 1.0 ml/kg, the combination of perflutren and US exposure resulted in capillary bleeding and increased endothelial cell injury in capillaries and venules (p<0.01). However, the incidence of microvessel bleeding and endothelial cell injury did not exceed that with Levovist microbubbles. In the myocardium, microvessel bleeding was not observed under any conditions. In conclusion, perflutren lipid microspheres enhanced US-related microvessel injury as with other contrast agents at the dose of 1.0 ml/kg, but not with 0.1 ml/kg and the appropriate US setting.

Usefulness of sonographic guidance during percutaneous biopsy of mesenteric masses

OBJECTIVE

The objective of our study was to determine the usefulness of sonographic guidance for biopsy of mesenteric masses.

MATERIALS AND METHODS

Twenty-five sonographically guided percutaneous biopsies of mesenteric masses were performed in 23 patients. Biopsies were performed with an 18-, 20-, or 22-gauge self-aspirating needle or core biopsy device. Final pathology results and patient medical records were reviewed for biopsy accuracy and complications. A biopsy was considered successful if a specific benign or malignant diagnosis was rendered by the pathologist or if surgical-pathologic confirmation was obtained.

RESULTS

Open surgical biopsy was performed after sonographically guided biopsy in 13 patients and led to 12 concordant diagnoses (nine true-positives and three true-negatives) and one discordant diagnosis (false-negative). Specific pathologic diagnosis was rendered for the 10 percutaneous biopsies that were not confirmed by surgical biopsy: five biopsies matched known primary malignancies, consistent with metastases; four biopsies revealed primary tumors, and one biopsy revealed chronic inflammation (nine true-positives and one true-negative). Two biopsies were nondiagnostic because of insufficient material (n = 1) and necrotic tumor (n = 1). In the biopsies with diagnostic tissue specimens, sonographically guided biopsy achieved a sensitivity of 95% (18/19) and specificity of 100% (4/4) for allowing neoplastic tissue to be distinguished from nonneoplastic tissue. Complications included a mesenteric hematoma and abdominal wall cellulitis.

CONCLUSION

Percutaneous biopsy of mesenteric masses is a useful and safe procedure.

Etiology of cecal and hepatic lesions in mice after administration of gas-carrier contrast agents used in ultrasound imaging

The aim of the study was to investigate the etiology of cecal and hepatic lesions in mice and rats after intravenous administration of gas-carrier contrast agents (GCAs). A modified fluorescein flowmetry technique and 24 h necropsy were used in mice (conventional and germ free), rats, and guinea pigs after GCA administration. Different diets and oral nonabsorbable antibiotics were used. Nonfluorescence, edema, congestion, hemorrhage, and mucosal erosion in cecum and colon and nonfluorescent areas in the liver were observed from 16 min after GCA administration in conventional mice on standard diet. Numerous gas bubbles (>50 microm) were observed in the vasculature around the nonfluorescent areas of cecum and colon and in mesenteric vessels draining to the portal vein. Acute inflammation, edema, hemorrhage, and ulceration of the cecum and colon and liver necrosis were seen 24 h after GCA administration in conventional mice on standard diet. When mice were maintained on either a diet with glucose as the only carbohydrate source or on a standard diet supplemented with antibiotics, uniform fluorescence and no organ lesions were observed after GCA administration. Uniform fluorescence and no organ lesions were observed in germ-free mice, rats, and guinea pigs dosed with GCAs and in control animals (mice, rats, and guinea pigs) dosed with sucrose. The results indicate that intravascular growth of GCA microbubbles occurs in the cecal and colonic wall of mice, leading to occlusive ischemia and necrosis in these intestinal segments and secondary gas embolisation in the liver. Transmural gas supersaturation in the cecal wall may explain the intravascular bubble growth in mice.

Intestinal and hepatic lesions in mice, rats, and other laboratory animals after intravenous administration of gas-carrier contrast agents used in ultrasound imaging

Single intravenous administration of three different gas-carrier contrast agents used in ultrasound imaging to mice caused inflammation, necrosis, and ulceration of cecum and proximal colon (cecocolonic area) and focal necrosis in the liver. Similar intestinal lesions were also found in rats after treatment with a single iv administration of a gas-carrier contrast agent. Strain differences in the incidences of these lesions were found in both rats and mice. HsdHan:NMRI mice were among the most sensitive of the strains of mice studied. Even at the lowest dose of Sonazoid technically possible to inject in HsdHan:NMRI mice, lesions were found and a no-effect dose could not be determined. In a time-course experiment in HsdHan:NMRI mice, it was found that the lesions began to develop in the cecum and colon within 15 to 30 min after dosing. Lesions in the liver were first observed 120-240 min after dosing. Diet played a role in the etiology of the lesions, as HsdHan:NMRI mice given a diet with reduced amounts of cellulose and starch had reduced incidences of lesions, and when glucose was the only carbohydrate source, no lesions were observed. No intestinal or hepatic lesions were found in guinea pigs or rabbits after repeated intravenous administrations of Sonazoid. In dogs, minimal to mild granulocytic inflammation of the cecum and/or colon was found after daily repeated intravenous injections for 28 days, but not after daily repeated administration for 14 days nor after a single administration. It is proposed that the intestinal and hepatic lesions in rats and mice after a single intravenous injection of gas-carrier contrast agents are caused by a common mechanism: intravascular growth of gas-carrier agents in tissues with gas supersaturation, as occurs in the cecal wall of rats and mice. In this particular environment the growing gas bubbles cause ischemia and necrosis in the cecal and colonic wall and liver. This proposed mechanism of action is consistent with the absence of clinical reports indicative of intestinal and/or hepatic lesions in humans after administration of gas-carrier contrast agents.

Time to threshold (TT), a safety parameter for heating by diagnostic ultrasound

Activities in the standardisation of medical ultrasonic imaging and monitoring devices have been undertaken to ensure the safe application and to provide the user with tools to perform risk-to-benefit analysis. Internationally, agreement has not been reached to implement a system based on a physical quantity such as temperature rise. Therefore, recently, the IEC Standard 60601-2-37 has adopted the thermal index (TI) as a safety parameter. TI indicates conditions that are more likely than others to produce thermal effects. The models used to calculate TI are based on the equilibrium temperature rise for a stationary transducer. Ultrasound (US) is often applied during a short time at one place. To characterise the situation before equilibrium is reached, this study proposes a new parameter: TT (time to threshold). TT indicates the time after which a threshold temperature rise is exceeded. TT is calculated for some tissue models to illustrate the meaning of TT. TT indicates how long one piece of tissue can be insonated safely, provided the safe threshold is known. Using TT, higher intensities can be applied safely during a limited time. This paper illustrates the effects of short insonation times and the influence of the beam diameter. Questions that are critical to the introduction of TT as a safety parameter are discussed.

Superthreshold behavior and threshold estimation of ultrasound-induced lung hemorrhage in pigs: role of age dependency

Age-dependent threshold and superthreshold behavior of ultrasound-induced lung hemorrhage were investigated with 116 2.1 +/- 0.3-kg neonate crossbred pigs (4.9 +/- 1.6 days old), 103 10 +/- 1.1-kg crossbred pigs (39 +/-5 days old), and 104 20+/-1.2-kg crossbred pigs (58 +/- 5 days old). Exposure conditions were: 3.1 MHz, 10-s exposure duration, 1-kHz pulse repetition frequency (PRF), and 1.2-micros pulse duration. The in situ (at the pleural surface) peak rarefactional pressure ranged between 2.2 and 10.4 MPa with either eight or nine acoustic pressure groups for each of the three pig ages (12 pigs/exposure group) plus sham exposed pigs. There were no lesions in the shams. Pigs were exposed bilaterally with the order of exposure (left then right lung, or right then left lung) and acoustic pressure both randomized. Pig age was not randomized. Individuals involved in animal handling, exposure, and lesion scoring were blinded to the exposure condition. Logistic regression analysis was used to examine the dependence of the lesion incidence rates on in situ peak rarefactional pressure, left versus right lung exposure, order of exposure (first versus second), and age in three age groups. Likewise, lesion depth and lesion root surface area were analyzed using Gaussian tobit regression analysis. A significant threshold effect on lesion occurrence was observed as a function of age; younger pigs were less susceptible to lung damage given equivalent in situ exposure. Overall, the oldest pigs had a significantly lower threshold (2.87 +/- 0.29 MPa) than middle-aged pigs (5.83 +/- 0.52 MPa). The oldest pigs also had a lower threshold than neonate pigs (3.60 +/- 0.44 MPa). Also, an unexpected result was observed. The ultrasound exposures were bilateral, and the threshold results reported above were based on the lung that was first exposed. After the first lung was exposed, the pig was turned over and the other lung was exposed to the same acoustic pressure. There was a significant decrease (greater than the confidence limits) in occurrence thresholds: 3.60 to 2.68, 5.83 to 2.97, and 2.87 to 1.16 MPa for neonates, middle-aged, and oldest pigs, respectively, in the second lung exposed. Thus, a subtle effect in lung physiology resulted in a major effect on lesion thresholds.

[Endobronchial ultrasonography]

Endobronchial ultrasonography is an imaging method which has been developed during the last decade. It can be performed by applying tools that are used today during conventional bronchofiberscopy. This method is recommended for identifying processes that affect the bronchial wall and the mediastinal lesions next to central airways as well as for localizing peripheral lung lesions. The authors present a compilation of publications and summarize their own experiences based on 44 cases of application of this method.

[Hysterosonography]

Hysterosonography, which consists in the injection of some cc of saline in the uterine cavity during sonography, allows an exploration of the uterine cavity and of the endometrium. Accuracy of hysterosonography is similar to that of office hysteroscopy. Hysterosonography distinguishes normal cavities from pathologic ones, endometrial atrophy from mucosal anomalies, polyps from myomas. Conversely, endometrial biopsy is still necessary for diagnosis of hyperplasia or cancer. Hysterosonography can also be proposed for first trimester bleedings, trophoblast retention or ectopic pregnancy. In the near future it could be applied to therapeutic goals such as sonographic section of polyps.

Effect of experimental therapeutic ultrasound on the distal antebrachial growth plates in one-month-old rabbits

The effect of therapeutic ultrasound (US) on the growth plates of growing bone was determined through fluorescence labelling and histopathological evaluation in one-month-old rabbits. Mean growth rates and mean heights of the growth plates of the US exposed radius vs. control radius, and US exposed ulna vs. control ulna showed no statistically significant differences at all intensities and time intervals. Mean growth rates and heights of the growth plates of the US exposed radius for 0.2 W/cm(2) (SATA) US vs. 0.5 W/cm(2) US showed the same type of pattern compared to those of the control radius for 0.2 W/cm(2)vs. 0.5 W/cm(2) at days 10, 15 and 20. Similar results were also found for the ulna. Effects of 0.5 W/cm(2) US on the mean growth rates and mean heights of the growth plates were superior to those of 0.2 W/cm(2) US at day 10. The results at day 10 were reversed for the same comparisons at days 15 and 20. No cavitation effect of US was observed on growth plate cells. There was no evidence of partial or complete premature closure of the growth plates or of angular deformity of the carpal region.

Microbubbles induce renal hemorrhage when exposed to diagnostic ultrasound in anesthetized rats

The generation of ultrasound (US) bioeffects using a clinical imaging system is controversial. We tested the hypothesis that the presence of microbubbles in the US field of a medical imager induces biologic effects. Both kidneys of anesthetized rats were insonified for 5 min using a medical imaging system after the administration of microbubbles. One kidney was insonified using a continuous mode (30 Hz) and the opposite kidney was insonified using an intermittent (1 Hz) technique. The microbubbles were exposed to three different transducer frequencies and four transducer output powers. After insonification, the animals were euthanized, the kidneys were removed and their gross appearance scored under "blinded" conditions using a defined scale. After the administration of microbubbles, US imaging of the kidney caused hemorrhage in the renal tissue. The severity and area of hemorrhage increased with an increase in the transducer power and a decrease in the transducer frequency. Intermittent insonification in the presence of microbubbles produced a greater degree of renal hemorrhage than continuous imaging techniques.

Safety of medical diagnostic ultrasound

The exemplary safety record of diagnostic ultrasound (DUS) is probably an important reason that it has become so widely used. Advances in technology and procedures promise to make it even more valuable. At the same time, some of these advances bring with them new situations where harm can occur unless they are given appropriate attention. Maintaining patient safety along with increasing benefits requires (1) a vigorous continuing research program for determining optimum operating conditions and (2) effective means for communicating guidance to users. In this article, a standard developed in the USA for displaying safety information is discussed.

Spontaneous homogeneous nucleation, inertial cavitation and the safety of diagnostic ultrasound

Gas bubbles of sufficient size to serve as cavitation nuclei may form spontaneously in tissue in regions of very low interfacial tension. In the absence of an acoustic wave or other mechanical stress, such nuclei will quickly dissolve and disappear from the medium. Under the influence of an acoustic wave, however, these microbubbles may grow to many times their initial size and then collapse violently, a process known as inertial cavitation. In this work, the in vivo energetics and dynamics of the nucleation-cavitation process were modeled by treating tissue as a homogeneous fluid. The assumption of a viscosity of 10(-3) Pa s (i.e., that of water) resulted in the lowest acoustic rarefactional pressure threshold for nucleation-cavitation events, approximately 4.0 MPa, which was essentially frequency-independent over the range 1 to 15 MHz. The rarefactional pressure threshold for a viscosity of 5 x 10(-3) Pa s (that of blood) also was approximately 4.0 MPa at 1 MHz, but the threshold for this higher viscosity increased nearly linearly with frequency above approximately 5 MHz, never being more than approximately 0.2 MPa below the equivalent derated peak rarefactional pressure calculated assuming MI = 1.9, the current USFDA guideline.

Models and regulatory considerations for transient temperature rise during diagnostic ultrasound pulses

A new diagnostic ultrasound (US) technique, sometimes called radiation force imaging, produces and detects motion in solid tissue or acoustic streaming in fluids via a high-intensity beam. Current models for estimating temperature rise during US exposure calculate the steady-state rise, using time-averaged acoustic output, as the worst case for safety consideration. Although valid for very short pulses, this analysis might not correspond to a worst-case scenario for the longer pulses or pulse bursts, up to hundreds of ms, used by this newer method. Models are presented to calculate the transient temperature rise from these pulse bursts for both the bone at focus and soft tissue situation. It is shown, based on accepted time-temperature dose criteria, that, for the bone at focus case and pulse lengths and intensities utilized by these methods, temperature may increase to levels that raise safety concerns. Also, regulatory aspects of this modality are analyzed in terms of the current FDA acoustic output limits for diagnostic US devices.

Temporal summation of pain from skin, muscle and joint following nociceptive ultrasonic stimulation in humans

This study investigated the phenomenon of temporal summation in response to repetitive focused ultrasound stimulation of skin, muscle and joint in human volunteers. Stimulation was carried out using a custom-designed, focused ultrasonic stimulator with a resonant frequency of 1.66 MHz. A series of stand-off attachments were used to ensure that the focal region of the ultrasound beam projected either cutaneously, within the distal interphalangeal joint of the index finger, or within the first dorsal interosseous muscle. Stimulation was carried out using single pulses and trains of five pulses of different pulse durations (25 ms, 50 ms, 75 ms, 100 ms), and using single pulses and trains of five pulses (50 ms duration) at different frequencies (0.5 Hz, 1 Hz, 2 Hz, 3 Hz, 4 Hz, 5 Hz). Tactile perception thresholds, pain thresholds and summation pain thresholds were recorded. Temporal summation of pain could be elicited by stimulation of both skin, joint and muscle, although the influence of temporal summation appeared to be more pronounced for muscle stimulation. Muscle stimulation also required greater ultrasound intensity compared with joint and skin stimulation. Temporal summation could not be elicited by tactile, low-intensity stimulation. Focused ultrasound is a potent, noninvasive technique with which to investigate temporal summation from somatic structures. A number of factors may account for the higher intensities required to elicit pain in muscle and the increased rate of temporal summation. It is clear, however, that if temporal summation is more pronounced in muscle than other tissues then this may be an important factor contributing to pain in musculoskeletal syndromes.

Lauriston S. Taylor Lecture: Assuring the safety of medical diagnostic ultrasound

In 1980, the NCRP formed Scientific Committee 66 with an assignment to address the subject of "biological effects of ultrasound and exposure criteria." It was recognized that the primary source of exposure to ultrasound was through medical applications and, especially, through procedures employing diagnostic ultrasound. While the risk to patients from these procedures was believed small, it was considered important for users to understand it, in view of the widespread use of diagnostic ultrasound. In proceeding with this assignment, much emphasis has been given to the mechanisms by which ultrasound can bring about changes in biological structures or processes. Thermal effects are possible; the local temperature can rise especially rapidly where ultrasound impinges on bone. From theory for heat production and transport, and by analysis of experimental results with mammals, information has been obtained for guiding users in avoiding harm from temperature elevation. Nonthermal effects, such as capillary rupture, can occur when ultrasound is incident on tissue that normally contains gas-filled cavities, as in adult lung or intestine, or on any tissue containing gaseous contrast agents. Theory from fluid dynamics, together with experimental findings, has led to quantitative guidance for avoiding damage from acoustically activated cavities. It is felt that good practice in applying diagnostic ultrasound is best assured by making it possible for users to be well informed on safety matters so that they can feel justifiably confident in making appropriate choices of operating conditions. A promising and useful approach is in the display of safety information on the diagnostic ultrasound screen, which is now a feature of United States standards.

[Users of ultrasound machines are often subjected to musculoskeletal could be preventive measures. Better work organization and equipment could be preventive measures]

Stress, musculoskeletal symptoms, and eye strain are common among users of ultrasound machines. The purpose of the study was to identify work situations that induce a psychosocial or physical load in work with ultrasound. 12 sonographers participated. Questionnaire and video-based interviewing methods were used. Effects of changes in work organisation and equipment that were introduced after the first study were followed up after 6 months (9 of the participants in the former study). The study confirmed that musculoskeletal symptoms were common. Work situations inducing physical and/or psychosocial loads were identified. Changes of the equipment and work organisation led to positive effects both in terms of the physical and the psychosocial load. Better work organisation and ergonomically designed equipment are measures that can prevent work-related disorders.