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PubMed1996

Ultrasonic assessment of human and bovine trabecular bone: a comparison study.

A comparison study is reported on the ultrasonic assessment of human trabecular and bovine trabecular bone samples. Both ultrasonic velocity and ultrasonic attenuation were evaluated through a transmission insertion technique and correlated with bone mineral density as determined with single photon absorptiometry. For a 1-MHz ultrasonic transducer pair and the human cancellous bone samples the correlations were 0.91 and 0.89 between density and velocity and attenuation, respectively. For a 500-kHz ultrasonic transducer pair the correlations were 0.89 and 0.81 between density and velocity and attenuation, respectively. For the bovine bone samples, the correlations were 0.90 and -0.31 for the velocity and attenuation, respectively, for the 1 MHz transducer pair. For the 500-kHz transducers, the correlations were 0.85 and -0.17 for the velocity and attenuation, respectively. By combining both velocity and attenuation in a multivariate regression, an improvement was achieved in the estimation of bone density in the human samples for both the 500-kHz and 1-MHz transducer pairs. No significant improvement was achieved in the multivariate regressions for the bovine bone samples. In conclusion, the results indicate that ultrasonic measurements are in general highly correlated with bone mineral density in trabecular bone samples. This correlation is more consistent and strong in relatively low density human samples compared with the higher density bovine samples.

Adult↗
PubMed2002

Experimental and simulated ultrasonic characterization of complex damage in fused silica.

The growth of a laser-induced, surface damage site in a fused silica window was monitored by the ultrasonic pulse-echo technique. The laser damage was grown using 12-ns pulses of 1.053-microm wavelength light at a fluence of approximately 27 J/cm2. The ultrasonic data were acquired after each pulse of the laser beam for 19 pulses. In addition, optical images of the surface and subsurface damage shape were recorded after each pulse of the laser. The ultrasonic signal amplitude exhibited variations with the damage size, which were attributed to the subsurface morphology of the damage site. A mechanism for the observed ultrasonic data based on the interaction of the ultrasound with cracks radiating from the damage site was tested using two-dimensional numerical simulations. The simulated results exhibit qualitatively similar characteristics to the experimental data and demonstrate the usefulness of numerical simulation as an aid for ultrasonic signal interpretation. The observed sensitivity to subsurface morphology makes the ultrasonic methodology a promising tool for monitoring laser damage in large aperture laser optics used in fusion energy research.

Journal Article↗
PubMed2004

Comparison of corneal thickness measurements using Orbscan II, non-contact specular microscopy, and ultrasonic pachymetry in eyes after laser in situ keratomileusis.

AIMS: To compare central corneal thickness measurements of three pachymetry devices in eyes after laser in situ keratomileusis (LASIK). METHODS: Central corneal thickness was measured in 203 eyes after myopic LASIK. Orbscan II scanning slit topography (Bausch & Lomb), SP-2000P non-contact specular microscopy (Topcon), and ultrasonic pachymetry (Tomey) were used in this sequence. RESULTS: Three devices gave significantly different corneal thickness readings (p<0.0001, repeated measure analysis of variance). The measurements of Orbscan II (445.6 (SD 60.0) microm) were significantly smaller than those of noncontact specular microscopy (467.9 (SD 40.2) micro m; p<0.0001, Tukey multiple comparison) and ultrasonic pachymetry (478.8 (SD 41.9) microm; p<0.0001). The value obtained with SP-2000P non-contact specular microscopy was significantly smaller than that taken with ultrasonic pachymetry (p<0.001). There were significant linear correlations between scanning slit topography and non-contact specular microscopy (Pearson's correlation coefficient r = 0.912, p<0.0001), non-contact specular microscopy and ultrasonic pachymetry (r = 0.968, p<0.0001), and ultrasonic pachymetry and scanning slit topography (r = 0.933, p<0.0001). CONCLUSION: In post-LASIK eyes, Orbscan II scanning slit topography significantly underestimated corneal thickness. Non-contact specular microscopy gave smaller thickness readings than ultrasonic pachymetry, but these two units showed an excellent linear correlation.

Adult↗
PubMedDate not supplied

The use of ultrasonication to study remineralisation of eroded enamel.

The aim of this study was to use ultrasonication and profilometry as methods to study de- and remineralisation of citric acid-eroded enamel at different pH values. Seventy-eight polished human enamel samples were divided into three test and three control groups of 13 specimens each. Three specimens of each group were chosen for SEM examination. The samples were exposed to 0.3% citric acid at pH 2.54, 3.2 or 4.5 for 2 h. The depths of the resulting lesions were measured by profilometry. The test groups were placed in artificial saliva and the control groups were stored in saline (0.9% NaCl) for 24 h and new profiles recorded. Finally all specimens were ultrasonicated in water for 5, 30, 120, 240 and 480 s with profilometric measurements at each time point. Ultrasonication of the test groups after remineralisation showed little effect on the lesion depth, whereas the control groups had an enamel loss of 2.1 microm at pH 2.54, 2.9 microm at pH 3.2 and 0.4 microm at pH 4.5 after 30-second ultrasonication. These differences from respective test groups were statistically significant at pH 2.54 and 3.2 but not at pH 4.5. Ultrasonication of control pH 2.54 and 3.2 specimens removed an amorphous covering layer to reveal a flattened surface with prisms outlined by prism boundaries. It can be concluded that remineralisation in artificial saliva stabilises the surface softened enamel against ultrasonication.

Analysis of Variance↗
PubMed1995

Alterations in ultrasonic backscatter during exercise-induced myocardial ischemia in humans.

BACKGROUND: Experimentally induced myocardial ischemia in animals causes tissue modifications that alter characteristics of the ultrasonic beam backscattered from the myocardial muscle. Alterations of backscatter parameters have been evidenced in human subjects with acute or remote myocardial infarction and during ischemia induced by angioplasty balloon occlusion or pharmacological stimuli. The effects of transient effort ischemia in humans have not been reported. The purpose of this study is to assess ultrasonic backscatter parameter changes induced by transient effort myocardial ischemia in human subjects. METHODS AND RESULTS: Nineteen patients with single left anterior descending coronary stenosis and 15 healthy subjects underwent ultrasonic backscatter analysis (parasternal long-axis view) at rest, immediately after a supine stress test, and 30 minutes later. Two windows were selected in each ultrasonic study: one encompassing the septum; the other, the posterior wall. Integrated backscatter was computed throughout the cardiac cycle, yielding a power curve relative to the midmyocardial region of the myocardial wall (excluding pericardial and endocardial borders). Five parameters were computed from the backscatter power curve: the maximum-minimum difference, amplitude and phase of the first harmonic Fourier fitting, phase-weighted amplitude, and time-averaged integrated backscatter difference from rest (an index of overall myocardial reflectivity). This protocol allowed comparison of the backscatter data from a region at risk of ischemia (the septum) with that from a region normally perfused (posterior wall) and a comparison with the same regions of the control group during the three ultrasonic studies. All backscatter indexes in the septum were altered significantly by exercise compared with rest values, whereas no changes were found in the normally perfused posterior wall or in the septum of the control group. All modified parameters returned to baseline values at the time of the recovery study. CONCLUSIONS: These data indicate that transient, exercise-induced ischemia is associated with reduction of the cardiac cycle-dependent variation of the integrated backscatter power curve, a temporal shift in the nadir of the power curve with respect to the R wave (phase increase), and a small but detectable increase of myocardial reflectivity. These changes may be detected noninvasively in humans with ultrasonic backscatter analysis.

Adult↗
PubMed2001

Ultrasonic examination: an alternative to chest radiography after central venous catheter insertion?

We evaluated ultrasonic examination as a diagnostic tool for catheter misplacement and pneumothorax after central venous catheter insertion. Physicians in the intensive care unit (ICU) performed the ultrasonic examinations, and the results were compared with those of chest radiography. Eighty-five central venous catheters (70 subclavian and 15 internal jugular) were inserted into 81 patients; 10 misplacements and one pneumothorax occurred. Ultrasonic examination feasibility was 99.6%. The only pneumothorax and all misplacements except one were diagnosed by ultrasound. Taking into consideration misplacements and pneumothorax research, ultrasonic examination did not give any false positive results. The mean time of the entire ultrasonic examination was 6.8 +/- 3.5 min, whereas 80.3 +/- 66.7 min were needed for the radiography (p < 0.0001). This study has suggested that ultrasonic diagnosis of catheter misplacement and pneumothorax related to central venous catheterization is a rapid and accurate method that can be easily performed by ICU physicians.

Adult↗
PubMed2006

Ultrasonic backscatter and attenuation (11-27 MHz) variation with collagen fiber distribution in ex vivo human dermis.

This ex vivo study explores the relationship of ultrasonic attenuation and backscatter to dermal microarchitecture by comparing ultrasonic measurements of these parameters (11-27 MHz) to a microscopic analysis of three parameters describing the collagen distribution (mean thickness and spacing of collagen bundles along the insonification direction and the percent area occupied by collagen). Skin samples (N= 31) were obtained from patients undergoing breast or abdominal reduction surgery. Radio-frequency (rf) signals were acquired in a B-scan format using an ultrasound system developed for skin imaging (Ultrasons Technologies, Tours, France). Ultrasonic data were analyzed to calculate average integrated backscatter (IBS in dB) and frequency dependence of backscatter (n, dimensionless) of each specimen at depths centered approximately 370,620 and 880 microm beneath the skin surface. Average integrated attenuation coefficient (IA in dB.cm(-1)) and frequency dependence of attenuation coefficient (beta in dB.cm(-1).MHz(-1)) were estimated across the depth between 240 and 1,000 microm. The three collagen distribution parameters were estimated using digitized microcopic fields from matched regions of histological sections stained with hematoxylin-eosin-saffron. No significant correlation was identified between collagen distribution parameters and IA or beta. For the most superficial depth studied in abdominal skin, n was inversely correlated to collagen bundle thickness (r = -0.67,p = 0.002) and percent area (r = -0.65,p = 0.003). At the same depth, IBS was inversely correlated to percent area of collagen (r = -0.51,p = 0.03). The rather high collagen packing (48 to 82% area) measured in histological sections and the inverse relationship observed between IBS and percent area of collagen suggest that a packing factor should be included in models relating skin collagen distribution to ultrasound spectral parameters. A better understanding of the relationship between ultrasound parameters and the microarchitecture of the dermis should help to interpret changes in ultrasonic parameters observed during in vivo ultrasonic skin examinations.

Abdomen↗
PubMed1998

Delivery of salbutamol to nonventilated preterm infants by metered-dose inhaler, jet nebulizer, and ultrasonic nebulizer.

To identify the most efficient device for the delivery of bronchodilator aerosol to nonventilated preterm infants with chronic lung disease, we compared the metered dose inhaler (MDI) used in conjunction with a non-valved spacer, an ultrasonic nebulizer with a small medication cup, and two jet nebulizers. The subjects were enrolled in two double-blind randomized crossover studies. In study A (n=10), each infant was given a nominal dose of 200 microg of salbutamol by a MDI (Ventolin) at 4 h intervals, and in random sequence via an Aerochamber (Neonatal Aerochamber) with its one-way valve removed, an ultrasonic nebulizer with a small cone-shaped medication cup (Siemens Electronics), and a jet nebulizer (Side-stream). Their functional residual capacity (FRC) and static respiratory system mechanics were measured before, and at 15, 30, 60, and 120 min after aerosol delivery. Study B (n=10) was carried out in an identical manner, but with a different jet nebulizer (Hudson). In both studies, administration of salbutamol aerosol via the MDI Aerochamber or ultrasonic nebulizer resulted in a significantly greater reduction in respiratory system resistance than via jet nebulizers. Furthermore, the use of MDI Aerochamber or ultrasonic nebulizer was associated with a greater degree of post-treatment tachycardia and improvement in FRC. The bronchodilating effect of salbutamol delivered via the ultrasonic nebulizer appeared to be slightly greater than that via the MDI-Aerochamber, receiving significance only in Study B. We conclude that both the metered-dose inhaler used with a nonvalved Aerochamber and the ultrasonic nebulizer with a small medication cup are both more efficient than the jet nebulizers in preterm infants.

Albuterol↗
PubMed1992

Evaluation of ultrasonic estimates of carcass fat thickness and longissimus muscle area in beef cattle.

Yearling crossbred feedlot steers (n = 495) and heifers (n = 151) were ultrasonically measured at the 12-13th rib interface 24 h before slaughter to evaluate the accuracy of ultrasonic measurements of fat thickness (BFU) and longissimus muscle area (LMAU) for prediction of actual carcass measures. Isonification was with an Aloka 210DX ultrasound unit equipped with a 12.5-cm, 3.0-MHz, linear array transducer by two technicians. Carcass fat thickness (BFC) and longissimus muscle area (LMAC) were measured 48 h postmortem. Differences between ultrasonic and actual carcass measures were expressed in actual (BFDIFF and LMADIFF) and in absolute (magnitude of BFDIFF and magnitude of LMADIFF) terms for backfat and longissimus muscle area, respectively. When expressed as percentages of the actual carcass measures, the average absolute differences indicated error rates of 20.6% for backfat and 9.4% for longissimus muscle area. Average actual differences (BFDIFF and LMADIFF) indicated that underprediction occurred more often than overprediction for both measures. The BFU was within .25 cm of BFC 70% of the time, and LMAU was within 6.5 cm2 of LMAC 53% of the time. Ultrasound measurements BFU and LMAU more accurately predicted BFC and LMAC in thinner and more lightly muscled cattle, respectively. Simple correlation coefficients between ultrasonic and carcass measures were .75 (P less than .01) for BF and .60 (P less than .01) for LMA. Analyses of variance of absolute differences between ultrasonic and carcass measures indicated no significant differences to exist between technicians. Predictive accuracy of ultrasonic measures did not change as the level of experience of technicians increased during the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1998

Evaluation of the accuracy of real-time ultrasonic measurements of backfat and loin muscle area in swine using multiple statistical analysis procedures.

Real-time ultrasonic measurements of 10th-rib backfat (BF10) and loin muscle area (LMA) were made by a single technician at four mean BW (67.4, 80.3, 93.4, and 104.9 kg) on live hogs to assess the accuracy of predicting carcass measurements before and at slaughter weight. Records were evaluated on 655 purebred barrows and 472 purebred gilts in two tests. Residual correlations-accounting for test, sex, and breed effects, among and between scans and carcass measurements--were moderate to high for BF10 (r=.69 to .82) and LMA (r=.57 to .68), with the largest correlations at 104.9 kg of live weight. Ultrasonic BF10 and LMA were within +/-4 mm and +/-6.45 cm2, respectively, of the corresponding carcass measurement 75.9 and 89.8% of the time. Sex differences for LMA bias were significant (P < .001); ultrasonic LMA was overestimated in barrows by .75 cm2 and underestimated in gilts by .91 cm2. Breed differences were significant (P < .001) for BF10 and LMA bias. Standard errors of prediction (SEP) for BF10 and LMA across the two tests were 3.46 mm and 4.04 cm2, respectively. The SEP for BF10 were 3.60 mm for barrows and 3.19 mm for gilts. The SEP for LMA were 3.77 cm2 for barrows and 4.22 cm2 for gilts. The SEP for BF10 within breeds ranged from 3.25 to 3.72 mm, and for LMA, ranged from 2.98 cm2 to 4.90 cm2. Ultrasound measurements overestimated the carcass measurement by .57 mm for carcasses measuring < 24.1 mm and underestimated by 2.81 mm carcasses with BF10 > 30.3 mm. Ultrasonic LMA overestimated the carcass by 2.35 cm2 in carcasses measuring < 32.5 cm2 and underestimated by 2.29 cm2 in carcasses measuring greater than 37.9 cm2. Results indicate that the magnitude of the carcass measurement affects bias and accuracy of prediction for real-time ultrasonic measurements of BF10 and LMA. The SEP statistic is more consistent in evaluating accuracy of ultrasonic measurement than bias, absolute deviations, and percentage of absolute deviation.

Adipose Tissue↗
PubMed2000

Cheese maturity assessment using ultrasonics.

The relationship between Mahon cheese maturity and ultrasonic velocity was examined. Moisture and textural properties were used as maturity indicators. The ultrasonic velocity of the cheese varied between 1630 and 1740 m/s, increasing with the curing time mainly because of loss of water, which also produced an increase of the textural properties. Because of the nature of low-intensity ultrasonics, velocity was better related to those textural parameters that involved small displacements. Ultrasonic velocity decreased with increasing temperature because of the negative temperature coefficient of the ultrasonic velocity of fat and the melting of fat. These results highlight the potential use of ultrasonic velocity measurements to rapidly and nondestructively assess cheese maturity.

Cheese↗
PubMed2003

Evaluation of adhesive defects using an ultrasonic pulse-reflection technique.

The purpose of this study was to examine the application of an ultrasonic pulse-reflection technique for the evaluation of adhesive defects. First, the sonic velocities in the enamel and dentin of human molars and bovine incisors were measured with a pulsar receiver attached to an ultrasonic transducer. The identification of the dentino-enamel junction and pulp-dentin interface using the ultrasonic method based on intrinsic sonic velocities showed good agreement with the actual measured thicknesses. Next, a cemented restoration with artificial faults was prepared. Half of the Au-Ag-Pd alloy plate area was cemented to the dentin slab using luting resin cement. The adhesive interface was evaluated with a high-resolution ultrasonic imaging system. Clear internal faults were evident from the ultrasonic tomogram. The findings of this study suggest that the ultrasonic pulse-reflection technique may be useful for inspecting and imaging structural defects of adhesive interfaces.

Animals↗
PubMed1993

Effect of serotonergic drugs on footshock-induced ultrasonic vocalization in adult male rats.

Modulation of ultrasonic vocalization (20-30kHz) emitted by adult rats under stressful conditions such as unavoidable foot-shock has been evaluated as a model of anxiety. The effects of 5-HT(1A) receptor agonists with different intrinsic activities and the role of other 5-HT(1) receptor subtypes, and of 5-HT(2) and 5-HT(3) receptors, in mediation of ultrasonic vocalization were studied, as were the effects of increasing serotonergic activity by administration of the 5-HT releaser fenfluramine or the 5-HT precursor 1-5 HTP. The time spent vocalizing 1-6min after four increascapable (1.0mA) footshocks was recorded. Drugs with affinity for 5-HT(1A) receptors (i.e. 8-OHDPAT, flesinoxan, ipsapirone, buspirone, gepirone, NAN-190) abolished the vocalization irrespective of their efficacy. The mixed 5-HT(1) receptor and beta-adrenoceptor antagonists (-)-alprenolol and pindolol inhibited foot-shock-induced ultrasonic vocalization, whereas (-) penbutolol was ineffective. The beta(1)-adrenoceptor antagonist metoprolol and the beta(2)-adrenoceptor antagonist ICI 118.551 were without effect. This suggests that (-)-alprenolol and pindolol act as partial 5-HT(1) agonists in the test model. The non-selective 5-HT(1) receptor agonists eltoprazine, m-CPP and 5-MeODMT and the 5-HT(2) receptor agonists DO1 and d-LSD also abolished the vocalization, whereas the 5-HT(2) receptor antagonist ritanserin and the 5-HT(3) receptor antagonists ondansetron, ICS 205-930 and zacopride were without effect. (-)-Penbutolol reversed 8-OHDPAT-induced inhibition. Ritanserin reversed DOI-induced inhibition of ultrasonic vocalization, but not 8-OHDPAT-induced inhibition. This suggests that there is no functional interaction between 5-HT(1A) and 5-HT(2) receptors in this model. Fenfluramine and 1-5-HTP dose-dependently inhibited footshock-induced ultrasonic vocalization. These findings indicate that the effect most likely is mediated by postsynaptic 5-HT receptors, although contribution by presynaptic 5-HT receptors cannot be excluded. In conclusion, this study indicates that 5-HT(1A) receptors and 5-HT(2) receptors are involved in mediation of ultrasonic vocalization.

Journal Article↗
PubMed1982

Evaluation of an ultrasonic amplitude depth analysis technique for pregnancy diagnosis in the cow.

Beef and dairy cows (n = 1,053) were tested for pregnancy on 7 farms by ultrasonic scanning. Accuracy was verified by comparison with rectal palpation. Rectal palpation was done 40 to 75 days after breeding and was considered 100% accurate for comparison purposes. Although diagnostic accuracy of the ultrasonic scanning technique was less than 100%, a confidence interval no larger than 2.3% indicated a high degree of precision for pregnant cows. The confidence interval in the nonpregnant category ranged from 9.2% to 11.8%, which was small in relation to the variation in ultrasonic scanning accuracy. However, considering the large number of cows and the experimental bias that was purposely introduced, the lower accuracy of the ultrasonic method was not unexpected. Cystic ovaries, partially involuted uteri, metritis, and high milk production prevalent at one location accounted for much of the variation observed and lowered the overall accuracy for all cows tested. The ultrasonic analyzer has potential in testing cows for pregnancy; however, technical improvements in machine configuration must be made and additional testing in controlled experiments and field trials must be conducted before an accurate analysis of this method can be made. At the present state of development, ultrasonic amplitude depth analysis cannot replace rectal palpation for diagnosis of pregnancy in cattle.

Animals↗
PubMed1980

Early pregnancy failure: study by ultrasonic and hormonal methods.

The value of ultrasonic and hormonal methods [plasma human chorionic gonadotropin (hCG), estradiol (E2), and progesterone (P)] was examined in 188 patients exhibiting different forms of early pregnancy failure. A negative ultrasonic result in the detection of fetal life signs after 9 weeks' gestation signified an unsuccessful outcome for the pregnancy in 100% of cases. On the other hand, the ultrasonic demonstration of fetal life predicted delivery in 90% of cases despite symptoms of threatened abortion. Pathologic levels of hCG or P signified a later miscarriage in 93% of cases, and their combination correlated with a 100% failure rate. In the diagnosis of ectopic pregnancy the combined application of ultrasound and plasma hCG levels seemed to be very useful; however it appears that the detection of blighted ovum should be based on the ultrasonic scanning only. The results of the present study indicate that ultrasonic examination can be regarded as the basic diagnostic method in the evaluation of early pregnancy failure. The determination of plasma trophoblastic hormones (especially hCG) seems to add valuable information to the ultrasonic findings in the actual diagnosis and evaluation of the later course of pregnancy only until 9 weeks' gestation.

Abortion, Spontaneous↗
PubMed1994

[Evaluating cervical ripening in late pregnancy by transvaginal B-ultrasonic scan].

The ripening of the uterine cervix was studied by using trans vaginal B-ultrasonic scanning against Bishop's scoring in 60 pregnancies in the 3rd trimester, yielding a conformity rate of 70%. All cases with a score > or = 6 by transvaginal B-ultrasound delivered naturally or shortly after induction. There were 22 cases shown immature by Bishop's scoring, of which, 18 found to be mature by B-ultrasonic scan. 5 of the 18 ended naturally and 13 following induction, while the 4 immature according to B-ultrasonic scan failed to come into labor. This proved that vaginal B-ultrasonic scanning is more accurate than Bishop's scoring. B-ultrasonic scanning on the perineum could display the internal cervical os but not the external, unless the body position was changed in different ways. Transabdominal B-ultrasound scanning did not clearly display the cervix and only one case revealed in the cervical canal, and the amniotic membrane. Thus, vaginal B-ultrasonic scanning has a higher rate of visualization and clearer pictures, being able to reflect correctly and objectively the cervical ripening, thereby providing a more reliable method for cervical ripening evaluation.

Adult↗
PubMedDate not supplied

[The design of a family of ultrasonic diagnostic units based on up-to-date computer technologies].

Small ultrasonic devices are now being used in medical practice. However, the vast majority of them represent designingly completed systems which cannot include additional soft- and hardwares to accumulate measurements and to set up databases, to make additional postprocessing, to transmit measurements along networks and telephone lines, etc. On the other hand, in our and foreign countries, work is under way in designing the systems of archiving and treating ultrasonic images, working places for a physician engaged in radiation diagnosis. But at the same time direct joining of ultrasonic equipment with standard computer facilities is impossible in many practical cases. To design ultrasonic devices by using Multimedia IBM PC technology which may integrate various informational media, such as display, sonic information, and textual data is one of the ways of solving this problem. With this, the hardwares of ultrasonic devices are realized in the construction of standard IBM PC modules. Sonomed ultrasonic devices may be considered to be alternatives of Multimedia IBM PC-based devices.

Diagnosis, Computer-Assisted↗
PubMed1998

Does the measurement of digital arterial pressure using the Doppler ultrasonic technique without testing for vasospasm to detect digital arterial occlusions make good sense?

BACKGROUND: An attempt was made to determine whether measurement of the systolic pressure with the Doppler ultrasonic technique can be used to detect occlusions of the digital arteries. PATIENTS AND METHODS: A total of 92 patients (44 women, 48 men) with an average age of 47.5 years (range: 19-82 years) were investigated. Of these, 17 were diagnosed with a primary Raynaud's syndrome, 45 with a secondary, and 5 patients with a suspected secondary Raynaud's syndrome; 25 patients had digital occlusions of varying genesis. In all patients, the Doppler ultrasonic technique was applied to measure the systolic pressure of the digital arteries of both hands at a room temperature of 21-24 degrees Celsius without any additional thermal (warm or cold) provocation or use of vasodilatory agents; the results obtained were compared with arteriographs of the hands. RESULTS: While the sensitivity of the Doppler ultrasonic technique was a very low 55%, the specificity was a very high 95%. With a prevalence of 68%, the positive predictive value was 96%, the negative predictive value 50%. In the case of angiographically patent digital arteries with no spastic narrowing, the Doppler ultrasonic-measured systolic pressure was up to 30 mmHg above, and up to 25 mmHg below, the systolic pressure measured in the ipsilateral brachial artery. A pressure gradient between upper arm and digital arteries of this order of magnitude therefore does not exclude pathological changes. Only angiography was able reliably to detect vascular stenoses and occlusions. CONCLUSION: Reliable exclusion of digital arterial occlusions using the Doppler ultrasonic technique without testing for vasospasm is not possible. Only occlusions of digital arteries together with simultaneous occlusions of hand arteries can be reliably detected. Owing to the considerable scatter of the systolic blood pressure gradient between brachial and digital arteries, the Doppler ultrasonic technique cannot be used to distinguish between patent and occluded digital arteries without the use of additional vasodilation.

Adult↗