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Compared with conventional duplex imaging, color-flow scanning facilitates the identification of veins (especially below the knee), decreases the need to assess Doppler flow patterns and venous compressibility, and allows veins to be surveyed longitudinally. These advantages translate into a less demanding and time-consuming examination. This study was designed to determine the accuracy of color-flow scanning for detecting acute deep venous thrombosis in patients in whom the diagnosis is clinically suspected and in asymptomatic patients at high risk for developing postoperative deep venous thrombosis. The diagnostic group included 77 limbs of 75 patients, and the surveillance group included 190 limbs of 99 patients undergoing total hip or knee replacement. All patients were prospectively examined with color-flow scanning and phlebography. In the diagnostic group, the incidence of thrombi in below-knee veins (47%) was approximately equal to that in above-knee veins (43%); but in the surveillance group, the incidence of thrombi in below-knee veins (41%) far exceeded that in veins above the-knee (3%). Nonocclusive clots and clots isolated to a single venous segment were more common in the surveillance group. In symptomatic patients, color-flow scanning was 100% sensitive and 98% specific above the knee and 94% sensitive and 75% specific below the knee. In the surveillance group, color-flow scanning was significantly (20 < 0.001) less sensitive (55%) for detecting thrombi, 93% of which were confined to the tibioperoneal veins. Negative predictive values were 100% and 88% for the diagnostic and surveillance limbs, respectively. Positive predictive values were 80% for the diagnostic limbs and 89°/o for the surveillance limbs. Color-flow scanning effectively excludes above-knee deep venous thrombosis in symptomatic patients and asymptomatic high-risk patients and predicts the presence of above-knee thrombi in patients in the diagnostic group with reasonable accuracy (97%). We conclude that color-flow scanning is as accurate as conventional duplex imaging and, because of its advantages, is the noninvasive method of choice for evaluating patients with suspected deep venous thrombosis. Its role in the surveillance of patients at high risk remains to be determined and awaits further clinical evaluation. (J VAsc SURG 1992;15:366-76.) Accurate diagnosis of lower extremity deep venous thrombosis (DVT) is critical to the care of patients with thromboembolic disease. It is estimated

The regeneration of connective tissue attachment is a major goal of clinical periodontics. Recent investigations on biochemically mediated periodontal regeneration have attempted to define the various biological response modifiers which may provide a mechanism for periodontal regeneration. Fibronectin and endothelial cell growth factor have been shown to selectively enhance periodontal ligament (PDL) cell adhesion, migration, and proliferation. In addition, dentin preconditioned with tetracycline HCl (TTC) or citric acid (CA) supports PDL cell adhesion, presumably by exposing collagen fibers. We have now extended these studies to include basic fibroblast growth factor (b-FGF) as a potential meditor of periodontal regeneration. Using AFSCM (assays for specific cell migration), b-FGF in concentrations as low as 10 ng per dentin block significantly stimulated PDL cell chemotaxis, while the antibody against b-FGF inhibited both the chemotactic and proliferative characteristics of the mitogen. We also found that 5 ng and above of b-FGF per dentin block significantly stimulated human endothelial cell migration and proliferation. Using 125I-b-FGF, we demonstrated that the factor binds to native dentin. This binding was increased when the dentin blocks were preconditioned by TTC or CA and reduced when the dentin was subsequently treated with collagenase. 125I-b-FGF also bound with moderate affinity to a type I collagen affinity column whereas the binding to a hydroxylapatite affinity column was negligible. The combination of FN and b-FGF was a marginally more potent chemo-attractant than b-FGF alone for PDL cells.(ABSTRACT TRUNCATED AT 250 WORDS)

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