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Dink A Legemate

Publications and source records attributed to Dink A Legemate.

22 records · Page 2Linked to original sources
PubMed2002

Color-flow duplex scanning of the leg arteries by use of a new echo-enhancing agent.

OBJECTIVE: This was a dose-finding and effectiveness study of a newly developed contrast-enhancing agent, sulphur hexafluoride (SF(6)), in patients with peripheral arterial disease in whom the therapeutic policy could not be established on the basis of standard color-flow duplex scanning of the leg arteries. METHODS: In this open-label, randomized, dose-ranging, crossover design, 14 patients in whom the assessment of vessel patency was difficult because of poor visibility (low-flow state) or extensive wall calcifications were studied. Contrast-enhanced duplex scanning was performed on the upper leg (n = 4), lower leg (n = 6), or pedal (n = 4) arteries after intravenous injection of four different dosages of SF(6). The results were compared with those from selective angiography of the vessel of interest. Contrast duration and agreement about the diagnosis and the confidence in the diagnosis were obtained before and after administration of the contrast agent. RESULTS: No adverse effects of the contrast agent were seen. Overall agreement was reasonable with regard to vessel patency between contrast-enhanced duplex scanning and angiography (71%). Nine of 14 vessels (64%) appeared open when contrast was applied. In four cases this could not be confirmed by angiography; in two of these cases this was due to the presence of collateral vessels. All vessels that appeared occluded with the contrast agent were also occluded on the angiogram. The confidence in the diagnosis increased from 56% to 91% after contrast administration (P <.0001). CONCLUSION: SF(6)-enhanced color-flow duplex scanning is a safe method that may improve the assessment of the patency of leg arteries, particularly in low-flow states. The visualization of collateral vessles during (enhanced) duplex scanning may be misleading because they may be regarded as the vessel of interest.

Aged↗
PubMed2002

Improved assessment of the hemodynamic significance of borderline iliac stenoses with use of hyperemic duplex scanning.

OBJECTIVE: To improve the assessment of the hemodynamic significance of borderline iliac stenoses (stenosis with a peak systolic velocity [PSV] ratio between 1.5 and 3.5) by means of hyperemic duplex scanning. The duplex ultrasound parameter-absolute increase in PSV across the stenosis after exercise (Delta PSV(e))-was studied prospectively. PATIENTS AND METHODS: Fifty-eight legs in 53 consecutive patients with symptomatic arterial obstructive disease with borderline iliac stenosis were studied prospectively. Ultrasound velocity data collected after exercise on a bicycle ergometer at 2 W/kg during 2 minutes were judged against the assessment of the hemodynamic significance by means of intraarterial pressure measurement, before and after the administration of 50 mg papaverine. RESULTS: On the basis of receiver operating characteristic curves traced for 43 iliac stenoses in 39 patients who finished the exercise, Delta PSV(e) > or = 1.4 m/s had optimal sensitivity of 93% (95% confidence interval [CI],.77-.99), specificity of 87% (95% CI,.60-.98), positive predictive value of 93% (95% CI,.77-.99) and negative predictive value of 87% (95% CI,.60-.98). CONCLUSIONS: The results of this study show that Delta PSV(e) with a cutoff value of 1.4 m/s in combination with the PSV ratio improves the assessment of the hemodynamic significance of borderline iliac artery stenoses if the patient can accomplish the workload.

Adult↗
PubMedDate not supplied

The fate of unrevised stenoses in infrainguinal autologous vein grafts as detected by intraoperative duplex scanning.

Intraoperative infrainguinal autologous vein graft stenoses are common, and some authors advise revision of these stenoses. But the natural history of these lesions is not clear. This study was undertaken to determine the natural history of duplex-detected intraoperative stenoses with a nonrevision policy. Intraoperative duplex scanning was performed in 46 infrainguinal autologous vein bypasses. The surgeon was blinded for the results of the intraoperative duplex scan and no intraoperative graft revision or modification of the routine postoperative protocol was performed after the duplex scan. Intraoperative duplex parameters and patient and bypass characteristics were correlated with the occurrence of an early graft event (occlusion or revision of a patent graft within 6 weeks postoperatively), which was the study's primary endpoint. Early graft event rate was 37% (17/46). PSV ratio and PSV-max were the only parameters with a significant correlation with the occurrence of an early graft event. An intraoperatively measured PSV ratio of > or =3.0 was the best predictor of an early graft failure with a sensitivity of 71% (95% CI: 50-83%) and a specificity of 90% (95% CI: 78-97%). In 12 of the 15 (80%) grafts matching this criterion an early graft event occurred, while only 5 (16%) early graft events occurred in the remaining 31 grafts (ie, a negative predictive value of 84%). When a PSV ratio of > or =3.0 was used as a cutoff value to predict early postoperative graft events, the likelihood ratios for a positive and negative test result were respectively 6.82 (95% CI: 2.23-20.8) and 0.33 (95% CI: 0.16-0.69). Unrevised intraoperative duplex-detected stenoses in infrainguinal autologous vein graft stenoses are a serious threat to early graft patency. The presence of an intraoperatively detected graft stenosis with a PSV ratio > or =3.0 is a strong predictor of early graft failure.

Constriction, Pathologic↗