Reliability of Doppler ultrasound in follow-up studies.

PURPOSE: To evaluate the reliability of repeat Doppler US measurements. MATERIAL AND METHODS: Nine radiologists conducted two sets of Doppler US measurements on a healthy volunteer, with a time interval of 9 months. Peak systolic velocity (PSV), resistance index (RI), and pulsatility index (PI) were measured 10 times in 4 arteries. RESULTS: There was considerable intra- and inter-observer variation both at baseline and 9 months later. The PSV values from the carotid artery varied from 0.27 m/s to 1.95 m/s in February and from 0.22 m/s to 1.38 m/s in November. The RI values from the renal artery ranged from 0.44 to 0.71 in February and from 0.41 to 0.67 in November. The results of the 9-month follow-up varied markedly too. Best reproducibility was achieved by highly experienced radiologists both at baseline and 9 months later. CONCLUSION: The short-term and long-term reliability of Doppler US was poor when the measurements were performed by a heterogeneous group of radiologists. The RI and PI measurements were somewhat more reliable than the PSV measurements and are recommended for use in follow-up studies.

Peak systolic velocity, resistance index and pulsatility index. Variations in measuring a pre-recorded videotape.

PURPOSE: To study variation in the process of measuring Doppler ultrasound (US) wave forms. MATERIAL AND METHODS: Eleven radiologists measured peak systolic velocity (PSV), resistance index (RI), and pulsatility index (PI) from a pre-recorded videotape. The wave forms were taken from the carotid, brachial, celiac, and renal interlobar arteries in a healthy volunteer. Each radiologist obtained measurements 10 times from a freely chosen wave form of 10 wave forms (10-beat series) and then a further set of measurements also 10 times from a specific wave form (1-beat series). RESULTS: There was a significant variation in all the PSV, RI and PI values measured, both in the 1-beat series and in the 10-beat series. The greatest variation was seen in the PI values: up to 5.1-fold. Both intraobserver and interobserver reproducibilities were poor. CONCLUSION: The process of obtaining measurements from an identified wave form is a major source of error in Doppler US studies. Special attention should be paid to this final phase of an examination. We recommend that measurements be obtained from more than one heart beat.

Reproducibility of Doppler ultrasound measurements.

PURPOSES: The reproducibility of Doppler ultrasound measurements was studied in a group of radiologists with different experience of such measurements. MATERIAL AND METHODS: The 12 participating radiologists measured peak systolic velocity (PSV), resistance index (RI), and pulsatility index (PI) from 3 arteries and PSV alone in one artery of a healthy person under standardized circumstances. Each participant repeated the measurements 10 times. RESULTS: Significant (p < 0.005) interobserver variation was seen in all of the variables, with an up to 14-fold difference in the PSV values measured and most variation resulting from differences between observers. The reproducibility of RI was better, most variation being within observers. Experience improved the reproducibility of the Doppler US measurements. Significant difference (p < 0.05) in Doppler US measurements was seen between the 3 experience groups. The difference was marked between the highly experienced and the medium experienced group when the variances of the measured values of PSV, RI, and PI from all 4 arteries were combined. CONCLUSION: The reproducibility of Doppler ultrasound measurements is poor. The value of the method is questionable.

Imaging of soft-tissue sarcomas with indium-111-labeled monoclonal antimyosin Fab fragments.

Some soft-tissue sarcomas contain intracellular myosin. We therefore studied the possibility of localizing various soft-tissue sarcomas with 111In-labeled monoclonal antibody Fab fragments binding specifically to myosin, assuming that damage to the cell membrane could expose intracellular myosin. Nineteen patients with different types of soft-tissue sarcomas were studied. Eighteen patients were found to have abnormal antibody uptakes. Antibody uptake was not observed in an additional patient operated for a benign tumor (gastric leiomyoma). The immunoscintigraphy results were generally in good agreement with those of other radiologic findings (computed tomography, ultrasound, magnetic resonance imaging). Surprisingly, the immunohistochemistry results showed that tumors not stainable for myosin can also be imaged with antimyosin. Thus, the mechanism of antibody uptake does not seem to be related entirely to specific antigen recognition. Irrespective of the exact mechanism for the uptake of labeled antibody this method appears to be useful for localizing soft-tissue sarcomas.

Accelerated tissue expansion with the "overfilling" technique.

Temporary overexpansion of the tissues at each filling session increased the actual inflation volume by about 59 percent. This shortened the process of tissue expansion considerably. "Overexpansion" means that the pressure in the expander is increased to a point where the dermal capillary flow is zero or the patient experiences so much discomfort that inflation cannot be carried out any further. The pressure in the expander is thereafter gradually decreased by taking out saline until both the capillary refill and all other clinical criteria are sufficient for safe dermal circulation. Comparison of the expander volume at the final pressure to the initial filling volume at the same pressure before the "overfilling" confirmed an average gain of about 59 percent in 14 patients.

Tissue expander injection dome leakage.

Injection dome leakage was found to be the cause for partial disappearance of the saline solution injected into some tissue expanders. When the injection domes of 22 consecutively removed tissue expanders were checked, we found that the average leakage pressure of these was 32 mmHg, with a range of 8 to 110 mmHg. When the patients were lying on their expanders, the weight of the corresponding body part caused intraluminal pressures of up to 90 mmHg in their expanders. Following removal of the expanders, the total leakage was calculated quantitatively and found to be maximally over 50 percent of the injected volume in some instances. The leakage flow through the injection dome in seven consecutively removed expanders was checked at pressures of 25, 50, and 75 mmHg over 30 minutes and was found to be slow. The possibility of injection dome leakage should be kept in mind, however, as a potential complication under unfavorable conditions. At the same time, we want to emphasize that in most instances tissue expanders function quite well and in predictable ways.

Validity of laser Doppler flowmetry for measuring the effect of the tissue expander pressure on skin circulation. Simultaneous measurement of tissue pressure and laser Doppler flowmetry.

Intermittent Laser Doppler Flowmetry (LDF) was used in five patients to measure changes in the dermal blood flow when changing intraluminal pressures in tissue expanders (TE). In another patient, continuous monitoring of the intraluminal pressure in the TE and simultaneous LDF was used. Our finding is that LDF is a suitable method for the registration of reactions in dermal circulation, caused by TE pressure changes. A statistically significant association between the changes of the LDF values and the intraluminal pressure in the TE was observed.