Duplexsonographie: Genauigkeit, Reproduzierbarkeit und Fehlermöglichkeiten: Überprüfung quantitativer Flußmessungen anhand eines Phantoms in vitro

Autor: A. Creutzig, F. Brassel, U. Roth, Alexander K, Hendrickx P, Ranke C
Rok vydání: 2008
Předmět:
Zdroj: DMW - Deutsche Medizinische Wochenschrift. 115:528-533
ISSN: 1439-4413
0012-0472
Popis: Using a pulsatile model of tubes, duplex-sonographic measurements of flow were compared with actual flow. The correlation coefficient between actual and duplex-sonographically obtained flow was 0.975, mean percentage deviation being -18.1% (P less than 0.0001). The obvious scatter (margin of error -69.2 to +50%) is to be explained by the simulation closely imitating a real situation: the transducer was hand-held and tubes were placed in muscle or fat tissue. Accuracy was increased by multiple measurements, especially when taking into account only the maximal value of any series of measurements. Vessel diameter was easy to measure accurately (mean error less than 0.01% [-18.7 to +9.4%]). Repeated measurements of flow velocity had only a small scatter (coefficient of variance 0.064). In muscle or fat the Doppler signal was attenuated and the error the greater the deeper the level at which measurements were made. Low flow (common in patients with obstructive vascular disease) can also cause faulty results.
Databáze: OpenAIRE