Higher Peak Systolic Velocity Research Articles

Spermatogenesis and spectral echo-colour Doppler traces from the main testicular artery.

To assess whether the peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistive index (RI) of testicular arteries may be useful in distinguishing the various causes of dyspermia when compared with follicle-stimulating hormone (FSH) and testicular volume. The study included nine men with obstructive and 20 with unobstruc-tive azoospermia, 17 with oligoasthenospermia and clinical varicoceles, with male accessory glans inflammation (MAGI), 38 with undetermined oligoasthenospermia, 19 with MAGI, 11 with clinical varicoceles, 32 subjects with normal sperm analysis and recent paternity (fertile controls), and 15 with normal sperm analysis and a varicocele with recent paternity (fertile + varicoceles). Testicular volume, FSH, PSV, EDV and RI were compared among the dyspermic and/or control groups using analysis of variance. The PSV and RI were useful for identifying the different groups of patients, while EDV, FSH and testicular volume were not. Men with varicoceles, varicoceles + MAGI or fertile with varicoceles had the highest PSV and RI; fertile controls, those with obstructive azoospermia and MAGI had similar PSVs and RIs, those with unexplained oligoasthenospermia had a significantly lower PSV and RI, and men with unobstructive azoospermia had the lowest PSV and RI. The RI and PSV are reliable indicators for routine clinical use to identify infertile/dyspermic men, while EDV, FSH and testicular volume are not. The RI and especially PSV clearly differentiated obstructive from unobstructive azoospermia.

Role of uterine artery Doppler flow in fibroid embolization.

To determine whether Doppler flow measurements are useful in predicting variables associated with uterine fibroid embolization, including shrinkage of the uterus and myomas, adenomyosis, and uterine fibroid embolization failure. A group of 227 patients with menorrhagia or postmenopausal bleeding secondary to uterine myomas were evaluated with uterine artery Doppler flow sonography before uterine fibroid embolization. Doppler flow measurements were repeated 6 months after uterine fibroid embolization for 188 of the patients. Data were analyzed for correlations between peak systolic velocity and uterine fibroid embolization patient data, including size and shrinkage of the uterus and myomas, embolization particle size, adenomyosis, and uterine fibroid embolization failure. Initial peak systolic velocity was positively correlated with the size and shrinkage of myomas and uterine volume. Peak systolic velocity was positively correlated with the size and load of embolization particles and was significantly lower (mean, 33.2 cm/s) in patients with adenomyosis than those without adenomyosis (mean, 39.3 cm/s). High peak systolic velocity (>64 cm/s) was a significant predictor of failure. Postembolization peak systolic velocity (mean, 21.85 cm/s) was significantly lower than preembolization peak systolic velocity (mean, 40.33 cm/s) and was not correlated with uterine fibroid embolization variables. Doppler flow measurements can aid in predicting adenomyosis and uterine fibroid embolization failure. Postembolization peak systolic velocity did not show value.

Intratumoral Blood Flow Analysis in Endometrial Carcinoma: Correlation with Tumor Characteristics and Risk for Recurrence

Objective.The aim of this study was to correlate intratumoral blood flow as assessed by transvaginal color Doppler ultrasound with tumor histopathologic characteristics, tumoral stage, and risk for recurrence in endometrial carcinoma.Methods. Forty-five patients (mean age: 58.2 years, range: 30 to 83 years) with surgically treated endometrial carcinoma preoperatively evaluated with transvaginal color Doppler ultrasound were included in this retrospective study. The lowest arterial resistance index (RI) and highest peak systolic velocity (PSV) were used for intratumoral blood flow analysis. Individual tumor characteristics evaluated were tumor growth pattern, tumor size, histologic type, tumor grade, myometrial infiltration depth, cervical involvement, lymph node metastasis, and lymph–vascular space invasion (LVSI). Tumoral stage and risk for recurrence were also evaluated.Results. Significantly lower RI was found in tumors with the following characteristics: infiltrative growth pattern (P = 0,013), grade 3 (P = 0.001), infiltrating ≥50% of the myometrium (P = 0.006), cervical involvement (P = 0.009), LVSI (P = 0.008), lymph–node metastasis (P = 0.049), stage ≥Ic (P = 0.004), and high risk for recurrence (P = 0.001). Significantly higher PSV was found in tumors that were grade 3 (P = 0.034), infiltrating ≥50% of the myometrium (P = 0.029), stage ≥Ic (P = 0.015), and with a high risk for recurrence (P = 0.002).Conclusions. Our data indicate that a correlation between intratumoral blood flow features and histopathological characteristics, tumor stage, and risk for recurrence exists in endometrial cancer. Further prospective studies are needed to determine the clinical usefulness of preoperative assessment of tumor vascularization in these carcinomas.

Color Doppler US in the Evaluation of Uterine Vascular Abnormalities

Uterine vascular lesions are rare but potentially life-threatening lesions that should be suspected in women of reproductive age with unexplained vaginal bleeding and in postmenopausal women in whom anechoic structures are detected at ultrasonography (US). This is especially true in patients with a history of infection, curettage, therapeutic abortion, pelvic surgery, endometrial carcinoma, or gestational trophoblastic disease. Color Doppler US is valuable in the detection and characterization of many uterine vascular lesions, including arteriovenous malformations (AVMs) (especially arteriovenous fistulas), true aneurysms, pseudoaneurysms, and chorioangioma of the placenta. Arteriovenous fistulas demonstrate a mosaic pattern representing turbulent flow. Spectral analysis of intralesional arterial flow demonstrates high-velocity flow with a low resistive index, and spectral analysis of intralesional venous flow shows high peak systolic velocities consistent with an arterial flow pattern. Spectral analysis of a true aneurysm demonstrates arterial signals, whereas a to-and-fro or swirling pattern of flow is seen at the neck of a pseudoaneurysm. Chorioangioma is a benign hypervascular lesion with arterial and venous flow that, like AVMs, contains numerous cystic spaces that produce color signals. Color Doppler US is useful in the early diagnosis and treatment of these potentially clinically significant disorders of the uterus and placenta. Response to treatment can also be assessed with this technique.

Nitric oxide synthase inhibition attenuates vasoactive response to spinal cord stimulation in an experimental cerebral vasospasm model.

The basic mechanism of delayed cerebral vasospasm following subarachnoid haemorrhage (SAH) has been intensively investigated. It is thought that nitric oxide (NO) is a basic mediator of the cerebral vasodilator mechanism. Previous clinical and experimental studies have shown a cerebral vasodilator effect of high cervical spinal cord stimulation (SCS) however, the mechanism of this effect is still controversial. We investigated the contribution of the vasodilator effect of NO to this mechanism in an experimental SAH model using rabbits. Four experimental groups, were designated: Group 1. Cerebral blood flow (CBF) was evaluated by transcranial Doppler ultrasonography (TDU) in 8 rabbits. Group 2. In 4 animals, intracisternal saline injection and cervical epidural electrode placement without SCS were performed before TDU. Group 3. TDU was performed before and after SCS on the fourth day of SAH in 8 rabbits. Group 4. In 8 animals, N-Nitro-L-Arginine Methyl Esther (L-NAME) was administered intracisternally on the fourth day of SAH, at a dose of 0.6 mg/kg, 45 minutes before SCS. CBF parameters, obtained via measurements or calculations from TDU data, were compared. The occurrence of vasospasm after SAH was demonstrated with significant changes in TDU parameters (high peak systolic velocity and positive values of the degree of stenosis). In all SAH animals, SCS resulted in significant vasodilation. Even after the injection of L-NAME, SCS still had a significant vasodilatory effect in SAH animals, but there was also a significant difference in CBF parameters in the SCS-only group when compared with the L-NAME treatment before SCS group. The mechanism of the cerebral vasodilatory effect of SCS remains controversial. Our results revealed the contribution of a neurohumoral effect which can be partially prevented by use of an NO synthase inhibitor.

Renal duplex sonography: Main renal artery versus hilar analysis

Objective: The purpose of this study was to compare the accuracy of main renal artery Doppler scanning interrogation and hilar analysis to diagnose hemodynamically significant renal artery disease. Methods: From January 1998 to August 1999, 41 patients had renal duplex sonography with both main renal artery interrogation and hilar analysis followed by angiography. They form the basis of this review. The sample consisted of 24 men and 17 women, with a mean age of 68.9 ± 10.2 years, who provided 80 kidneys for comparative analysis. Significant renal artery disease revealed through angiography was defined as ≥ 60% diameter-reducing stenosis or occlusion. Peak systolic velocity (PSV) (in meters per second) and the presence of poststenotic turbulence (PST) were determined from main renal artery interrogation. Acceleration time (AT) (in milliseconds) was measured by means of hilar analysis. Significant renal artery stenosis was defined by a PSV of 2.0 m/s or more and a PST or an AT more than 100 ms. Sensitivity analyses of both PSV and AT were examined, and 95% CIs were computed. Receiver operating characteristic curves were used to estimate optimal values for PSV and AT. Results: Angiography revealed hemodynamically significant fibromuscular dysplasia in 5 kidneys (4 patients), atherosclerotic stenosis ≥ 60% in 48 kidneys (30 patients), and renal artery occlusion in 4 kidneys (4 patients). Kidneys with significant renal artery stenosis had a higher PSV (2.54 ± 0.11 vs 1.28 ± 0.08, P <.001) and AT (82.43 ± 7.2 vs 30.0 ± 2.8, P <.001) compared with those without stenosis. Compared with angiography, a PSV of 2.0 m/s or more and PST demonstrated a sensitivity of 91%, specificity of 96%, and overall accuracy of 92% for detection of significant renal artery stenosis. Two of five studies with false-negative results reflected diseased polar vessels. By contrast, AT of more than 100 ms had a sensitivity of 32%, specificity of 100%, and overall accuracy of 54%. Receiver operating characteristic curve analysis revealed a PSV of more than 1.8 m/s and an AT of 58 ms or greater as optimal values. With an AT of 58 ms or more, the sensitivity was 58%, and specificity was 96%, with an overall accuracy of 70%. There were no apparent associations between PSV or AT and type or location of renal artery lesion, serum creatinine level, or end-diastolic ratio. Conclusion: Main renal artery interrogation is an accurate screening test to detect significant stenosis or occlusion of the main renal artery. Hilar analysis alone does not provide sufficient sensitivity to be used as a sole screening study. Neither method detects the presence of renovascular disease associated with polar vessels. (J Vasc Surg 2000;32:462-71.)

Interocular difference in progression of glaucoma correlates with interocular differences in retrobulbar circulation

PURPOSE: To evaluate the correlation between interocular difference in progression of glaucomatous damage and interocular differences in retrobulbar blood flow. METHODS: On the basis of a retrospective analysis of visual fields, progressive damage was identified in 20 patients with primary open-angle glaucoma. As a parameter of interocular difference in progression of visual field damage, the angle (gamma) between the regression lines of the visual field index mean defect over time per eye was calculated for each subject. The relationship between the angle gamma and interocular differences in intraocular pressure and retrobulbar color Doppler imaging parameters was analyzed by a multiple linear regression analysis in a stepwise forward approach. RESULTS: With larger interocular differences in progression of glaucomatous damage, lower mean blood flow velocities in the ophthalmic artery (partial r = −.69; P < .0016), higher resistivity indices in the central retinal artery (partial r = .48; P < .0456), and higher peak systolic velocities in the ophthalmic artery (partial r = .52; P < .0285) were noted in the eyes with more marked progression of damage (multiple r = .71; P < .0099). Interocular differences in progression of visual field damage were not related to intraocular pressure or extent of visual field damage. CONCLUSION: Independent of the extent of the interocular difference in glaucomatous damage and intraocular pressure, interocular difference in progression of glaucomatous visual field damage correlates with interocular difference in retrobulbar hemodynamic parameters.

Asymptomatic internal carotid artery stenosis defined by ultrasound and the risk of subsequent stroke in the elderly. The Cardiovascular Health Study.

We sought in this study to relate carotid ultrasound findings in asymptomatic older adults to the 5-year risk of various cerebrovascular outcomes used in the Asymptomatic Carotid Atherosclerosis Study (ACAS). The Cardiovascular Health Study (CHS) is a longitudinal study of people 65 years and older. Analyses of internal carotid artery stenosis defined by multiple different cutoffs of peak systolic velocity, rather than one particular cutoff, were performed in the 5441 participants who underwent carotid ultrasound and lacked a history of transient ischemic attack or stroke. The 5-year risks of 7 cerebrovascular disease outcomes used in ACAS were estimated for each cutoff. Associations with the 5-year risk of outcomes were substantially elevated only at cutoffs with high peak systolic velocities. In this population, the number of people with such high velocities was small. For example, with a cutoff of approximately 2.5 m/s, suggesting a stenosis of >70%, the 5-year risk of an ipsilateral fatal or nonfatal stroke was 5%, and only 0.5% of the group had velocities at least this high. In a group of older adults likely to participate in a screening program, as evidenced by willingness to participate in CHS, high peak systolic velocities consistent with high-grade carotid stenosis were uncommon and risk of subsequent cerebrovascular disease outcomes was relatively low. These findings do not suggest that similar populations of older adults would benefit from a program using ultrasound to screen for asymptomatic carotid stenosis.

Diagnosis of pulmonary arteriovenous malformations by colour Doppler ultrasound and amplitude ultrasound angiography

BACKGROUNDThe clinical value of colour Doppler ultrasound and amplitude ultrasound angiography in the diagnosis and follow up of pulmonary arteriovenous malformations (PAVM) was investigated.METHODSSix consecutive patients suspected by clinical appearance...

Preovulatory Changes of Blood Flow in Different Regions of the Human Follicle

Objective: To assess regional changes in ultrasound-derived indices of blood flow in the dominant human follicle after the plasma LH surge. Design: A cross-sectional, prospective study. Setting: Reproductive medicine unit at a university. Patient(s): Women attending an assisted conception clinic to determine the appropriate time to transfer previously frozen embryos during a natural cycle. Intervention(s): Transvaginal ultrasonography with color Doppler imaging and pulsed Doppler spectral analysis was used to obtain indices of blood flow and velocity from vessels in the base, lateral part, and apex of the dominant follicle on days 10–12 (from day 1 of menses) and after the LH surge, but before rupture. Immunoassays were used to measure the blood concentrations of LH twice daily (at 8–10 a. m. and 4–6 p. m.) from cycle day 10. Main Outcome Measure(s): The pulsatility index (PI), resistance index (RI), peak systolic velocity (PSV), and time-averaged maximum velocity (TAMXV) in the uterine arteries and three regions of the dominant follicle (apical, lateral, and basal parts); follicular volume; the day and time of the onset of the LH surge (defined as first concentration of LH >22 U/L) and the times of each scan. Result(s): Twenty-two women (aged 28–39 years) were studied and seven were scanned on days 10–12. A retrospective examination of the data from the remainder showed that eight were scanned <20 hours after onset of the LH surge and seven were scanned >20 hours after the onset of the LH surge. There was a significant increase in follicular volume after the LH surge. The PI was similar in vessels from the base (0.86 ± 0.11; mean ± SEM), lateral part (0.72 ± 0.51) and apex (0.67 ± 0.09) at cycle days 10–12 and then gradually decreased in the apex. There were similar changes in the RI. The PSV (mean ± SEM; cm/s) was similar in vessels from the base (10.1 ± 1.64), lateral side (8.2 ± 1.43), and apex (9.2 ± 1.91) in follicles of days 10–12. Within 20 hours of the onset of the LH surge, the PSV had increased in basal vessels (23.4 ± 4.10), remained similar in lateral vessels (11.64 ± 3.18), and was undetectable in apex vessels from six of eight follicles. Twenty hours after the LH surge, there was no pulsatile blood flow observed in the apical part of the follicle, but there was a sustained high PSV in the base (15.73 ± 3.42) and lateral side (9.02 ± 1.5). There were corresponding changes in the TAMXV. Conclusion(s): During the ovulatory process there are prominent changes in the regional blood flow of the follicle with a marked increase of the flow to the base of the follicle and a concomitant decrease of blood flow to the apex. These changes may be essential for the release of a mature oocyte.

Association of thymidine phosphorylase concentration with ultrasound-derived indices of blood flow in ovarian masses.

The aim of this study was to determine the relationship between the concentration of thymidine phosphorylase (a known angiogenic factor) and indices of blood flow in physiologic ovarian tissues and overt (benign and malignant) tumors. The ovaries of all patients were examined by transvaginal ultrasonography, with color Doppler imaging and pulsed Doppler spectral analysis, within the 24 hours preceding laparotomy. Ovaries removed at surgery were dissected into their main components (follicles, corpus luteum, and tumor) and, where possible, into areas of high blood velocity according to the results of color Doppler imaging. The concentration of thymidine phosphorylase was measured by an enzyme-linked immunosorbent assay. Thirty-eight tissue aliquots (16 from normal ovaries and 22 from ovarian tumors) were obtained from 33 patients. Twenty-nine tissue samples (76%) came from areas of measurable (high) blood velocity. The concentration of thymidine phosphorylase was significantly higher in tissue associated with high blood velocity (median 17.9, range 1.8-78.3 units per mg of protein vs. median 6.8, range 1.3-24.7 units per mg of protein, respectively; P < 0.05, Mann-Whitney U test). All of 8 corpora lutea, 12 of 14 benign tumors, and 7 of 7 malignant tumors had measurable blood velocity. There was a significant correlation between the concentration of thymidine phosphorylase and the peak systolic velocity in benign tumors (correlation coefficient [r] = 0.79, P < 0.01) and malignant tumors (r = 0.87, P < 0.05). High intratumoral peak systolic velocity as determined by transvaginal color Doppler imaging and spectral analysis reflects high production of thymidine phosphorylase. This finding may aid the development of antivascular therapy for patients with ovarian carcinoma.

Expression of thymidine phosphorylase in uterine sarcoma and uterine leiomyoma: association with microvessel density and Doppler blood flow analysis.

The aim of this study was to determine whether the expression of thymidine phosphorylase (TP) by uterine sarcoma and leiomyoma cells is associated with the density of microvessels within the tumor, and with Doppler ultrasound-derived peak systolic velocity (PSV) of blood flow. Sections of tissue from four uterine sarcomas and 41 uterine leiomyomas which had been used in a previous study to determine intratumoral peak systolic velocity were analyzed for the cellular expression of TP and the intratumoral density of microvessels by immunohistochemistry, using monoclonal antibody to TP and factor VIII-related antigen, respectively. The main outcome measures were whether or not the tumor cells were TP-positive or TP-negative, and the microvessel count within each tumor type. Uterine sarcomata were classified as TP-positive and uterine leiomyomata as TP-negative. The microvessel count in uterine sarcomas was significantly higher than that in uterine leiomyomas (p = 0.002, Mann-Whitney U test). We concluded that the expression of TP by uterine sarcoma cells is associated with an increase in microvessel density and with a higher peak systolic velocity.

Transplanted renal artery: detection of stenosis with color Doppler US.

To evaluate the influence of various parameters on peak systolic velocity in the transplanted renal artery and to define the normal range of peak systolic velocity. Color Doppler ultrasonographic (US) findings in 105 patients were reviewed. There were no clinical or biologic findings suggestive of a stenosis in the transplanted renal artery in these patients. The peak systolic velocity in the transplanted renal and external iliac arteries and the renal resistive index were measured. A large range of peak systolic velocities was noted in the transplanted renal artery. Peak systolic velocity in the renal artery was statistically significantly correlated with that in the external iliac artery when there was no pronounced vessel curvature. There was no relationship between peak systolic velocity and resistive index or time between transplantation and US. High peak systolic velocity was associated with a pronounced vessel curvature. The normal range of peak systolic velocity in the transplanted renal artery has considerable variability. Because of the strong correlation, the ratio of velocity in the renal artery to that in the external iliac artery may be useful in detection of stenosis.

Effects of indomethacin on follicular structure, vascularity, and function over the periovulatory period in women

To assess the effect of indomethacin (taken at defined times) on follicular rupture, indexes of intrafollicular blood flow, and steroidogenesis.Six healthy volunteers awaiting treatment for infertility by IVF-ET during subsequent natural cycles.All women were examined (at least every 8 hours) by transvaginal ultrasonography with color Doppler imaging and had samples of blood taken for hormone analysis. A self-test for urinary LH was performed before each scan. Indomethacin was first taken (50 mg three times per day) according to the maximum follicular diameter (first four women) or when the LH dipstick gave a positive result; the drug was taken for > or = 3 days.Follicular rupture was delayed in five of six cases (by 2 to 12 days). There was a reduction in intrafollicular peak systolic velocity before and after the positive urinary LH test compared with historical controls. Three follicles (50% of women) with the highest peak systolic velocity had an hemorrhagic appearance and persisted longer. There was no significant effect on menstrual cycle length or the levels of circulating FSH, E2, LH, or P.Indomethacin administered at the time of a positive self-test for urinary LH can delay follicular rupture with an associated reduction in intrafollicular blood flow but with no apparent effects on hormonal or menstrual status.

Blood velocity wave form characteristics of superior mesenteric artery and anterior cerebral artery before and after ductus arteriosus closure

Objective: To investigate the blood supply to intestines and brain in the preterm newborn with hemodynamically important patent ductus arteriosus (PDA), and to assess its change after proven ductal closure using color Doppler imaging. Methods: Velocity wave forms of the anterior cerebral artery (ACA) and the superior mesenteric artery (SMA) were obtained before and 12 h after closure of PDA in 14 preterm infants. Results: During PDA, abnormal high peaksystolic blood flow velocities (PSFV) were found in the SMA but not in the ACA, with mostly negative or abnormally low end-diastolic flow velocities (EDFV) in both investigated arteries. In the six infants whose ductus eventually closed, PSFV and EDFV of the SMA normalized to reference values which was not the case in the eight infants whose ductus remained open. PSFV and EDFV values of the SMA were not different compared to pre-indomethacin levels. Temporal mean blood flow velocities of SMA and ACA, used as a relative measure of intestinal and cerebral blood flow, respectively, did not differ before and after ductus closure. Conclusion: These results suggest a compensatory increase of PSFV of SMA during PDA to maintain an adequate intestinal blood supply.

Correlation of uterine hemodynamics with chemotherapy response in gestational trophoblastic tumors.

To assess the uterine hemodynamics in gestational trophoblastic tumors and to correlate them with response to chemotherapy. Using transvaginal color Doppler ultrasound, we measured the peak systolic velocity and the resistance index (RI) of the uterine arteries in 23 women with gestational trophoblastic tumors before each course of chemotherapy. Fifty-five nonpregnant women and another 15 women who had uneventful molar evacuation were enrolled as controls. Two-tailed Student t test was used for statistical analysis. A hyperdynamic uterine circulation was noticed at diagnosis in all gestational trophoblastic tumors, manifested as higher peak systolic velocity (mean +/- standard deviation 57.5 +/- 20.4 cm/second) of the uterine arteries compared to nonpregnant (28.3 +/- 3.41 cm/second; P < .0001) and uneventful post-mole uteri (26.8 +/- 3.08 cm/second; P < .0001). The RI values of the uterine arteries in gestational trophoblastic tumors at diagnosis ranged from 0.21-0.80. However, the mean value (0.56 +/- 0.19) was lower than those of nonpregnant (0.80 +/- 0.05; P < .0001) and post-mole uteri (0.75 +/- 0.06; P < .0001). A higher pre-treatment uterine artery RI (mean 0.71 +/- 0.09) was noted in ten patients with gestational trophoblastic tumors requiring fewer than five courses of chemotherapy, compared with the mean in 13 patients requiring longer courses of treatment (0.47 +/- 0.14; P < .0001). There was a marked decrease of peak systolic velocity during the first three courses of treatment in the former group (54.2 to 23.6 cm/second; P < .001), in contrast to no change in the latter group (60.1 to 60.5 cm/second). Uterine hemodynamic characteristics assessed by color Doppler ultrasound might predict and monitor the response to chemotherapy in gestational trophoblastic tumors.

Role of duplex Doppler ultrasound in the assessment of patients with postprandial abdominal pain.

In 10 patients with postprandial abdominal pain thought likely to be the result of mesenteric ischaemia Doppler ultrasound examinations of the superior mesenteric and coeliac arteries were performed both after fasting and a standard meal of 800 kcal. Compared with control values Doppler waveform analysis suggested seven abnormal vessels. Two patients had abnormal fasting superior mesenteric artery waveforms manifested by very high peak systolic velocities together with spectral broadening (one also had evidence of coeliac artery stenosis), and one patient had normal velocities but an abnormal signal and evidence of proximal superior mesenteric stenosis was supported by colour Doppler imaging and confirmed by angiography. Postprandially, two patients showed very high peak systolic and end diastolic velocities in the superior mesenteric artery (one had had a normal fasting waveform signal) and one in the coeliac artery, suggestive of vascular stenosis, while one patient showed a fall in peak systolic velocity. The diagnosis of mesenteric ischaemia in two of these patients was supported by digital subtraction angiography and abdominal computed tomography. Doppler ultrasound may be a useful non-invasive investigation for patients with postprandial abdominal pain that helps to select patients for angiography. Patients with tight vascular stenosis may have abnormal fasting Doppler waveform patterns but in symptomatic patients further information may be obtained after the haemodynamic stress of feeding. Additional information to enhance the diagnostic sensitivity of the test may be obtained by colour Doppler imaging.

Lower-extremity vascular grafts placed for peripheral vascular disease: prospective evaluation with duplex Doppler sonography.

Eighty-five men with 92 vascular grafts placed for peripheral vascular disease of the lower extremity underwent a total of 264 examinations with duplex Doppler over a 2.5-year period. In 64 patients who underwent more than one examination, the total follow-up encompassed 740 months. In 220 native femoral arteries (96.0%) the peak systolic velocity (PSV) was higher than that in the graft. Arteriovenous shunting was associated with a normal PSV and a markedly elevated diastolic component at spectral analysis. Focal fluid collections were common initially near the graft and usually disappeared uneventfully. An average PSV of 32 cm/sec or less was always associated with impending occlusion. The sensitivity of an average PSV of 40 cm/sec or less to indicate impending graft occlusion by the next visit was only 33%; the specificity, 94%. At initial examination, stenoses were associated with high PSV focally in the graft or low PSV with absent diastolic flow.

A duplex criterion for aorto-iliac stenosis

Duplex scanning is a new non-invasive test, which enables direct evaluation of aorto-iliac stenoses. The usual duplex criterion for an arterial stenosis is local increase in peak systolic velocity. For haemodynamically significant aorto-iliac stenoses a threshold value for this increase has not yet been established. In order to define a duplex criterion for significant aorto-iliac disease. The whole segment was scanned to locate areas with high peak systolic velocities which were then compared to the velocities recorded immediately up and downstream. The value of the highest proportional velocity change was used as the criterion for duplex classification of the segment. Duplex results were compared to the outcome of invasive femoral artery pressure measurements combined with reactive hyperaemia (FAP test). For a range of threshold values of the duplex criterion the specificity and sensitivity was calculated using the FAP test as the gold standard (R.O.C. analysis). The combinations of the highest sensitivity and specificity were obtained in the range of 100-200% change in peak systolic velocity as duplex criteria for significant aorto-iliac stenosis. The highest accuracy (88%) was obtained at a 200% change in the peak systolic velocity.

Sonographic Findings of Uterine Leiomyosarcoma

We describe herein various sonographic features of uterine leiomyosarcoma. Transabdominal scanning (TAS) revealed an image indistinguishable from benign leiomyoma, with evidence of degeneration. Transvaginal scanning (TVS) clearly showed the thinness of the myometrium, and the possibility of deep myometrial invasion was suspected at intraoperative open direct ultrasonography (ODU). A very high peak systolic velocity and a slightly increased diastolic component at the periphery of the tumor were evident with pulsed Doppler ultrasound. Thus, TAS, TVS, ODU and Doppler ultrasound will yield useful information for the physician attempting to evaluate the extent and vascularity of uterine leiomyosarcoma.