1.
Gudmundsson, Saemundur, et al.
(författare)
Factors affecting color Doppler energy ultrasound recordings in an in-vitro model
1998
Ingår i: Ultrasound in Medicine and Biology. - 0301-5629. ; 24:6, s. 899-902
Tidskriftsartikel (refereegranskat) abstract
Compared to conventional color Doppler ultrasound imaging, the new color Doppler modality "color Doppler energy" (CDE) has improved the possibility of visualizing blood vessels having low blood-flow velocities, but appears to be influenced by the settings of the ultrasound instrument and motion artefacts. The aim of this methodological study was to evaluate the effects of the different factors on the CDE signal. The CDE mode of a commercially available ultrasound system (Acuson 128 XP) was tested in an in vitro study. The effect of depth, angle of insonation, flow velocity, instrument power output, gain and other instrument settings were evaluated. The CDE signals obtained were stored on videotape and subsequently subjected to off-line computer analysis. The CDE signal intensity was found to be influenced mainly by fluid flow velocity, but was also affected by depth and instrument settings. Gain and power had, however, limited influence in this setting. Thus, the intensity of the CDE signal is influenced by several factors. Our results emphasize the need for optimum fixed preinstalled instrument settings when attempting to quantify organ perfusion by use of this new technique.
2.
Sladkevicius, Povilas, et al.
(författare)
Interobserver agreement in the results of Doppler examinations of extrauterine pelvic tumors
1995
Ingår i: Ultrasound in Obstetrics & Gynecology. - : Wiley. - 1469-0705 .- 0960-7692. ; 6:2, s. 91-96
Tidskriftsartikel (refereegranskat) abstract
The aim of this study was to evaluate interobserver agreement in the results of Doppler measurements of peak systolic velocity (PSV), time-averaged maximum velocity (TAMXV) and the color content of tumor scans in extrauterine pelvic tumors. The results of transvaginal color and spectral Doppler examinations of 66 extrauterine pelvic masses obtained by two observers experienced in ultrasonography were compared. Each observer aimed to obtain the highest possible Doppler shift from arteries in the wall, septa and solid parts of each tumor. Tumor vascularization was assessed in terms of the 'tumor color score', i.e. the color content of the Doppler scan as rated for the tumor as a whole by each observer on a visual analog scale. The tumors were classified according to arbitrarily chosen cut-off limits for the tumor color score, the highest tumor TAMXV and the highest tumor PSV. Inter-class correlation coefficient values for TAMXV and PSV were < or = 0.75, whereas that for tumor color score was 0.89. Interobserver agreement was complete for the detection of color in tumors (Kappa value 1.0), excellent for the recording of arterial Doppler shift spectra from tumors (Kappa value 0.82), and moderate or good for classifying tumors based on cut-off limits for TAMXV, PSV (Kappa values ranging from 0.44 to 0.67) and tumor color score (Kappa values ranging from 0.59 to 0.66).(ABSTRACT TRUNCATED AT 250 WORDS)
3.
Sladkevicius, Povilas, et al.
(författare)
Reproducibility of Doppler measurements of blood flow velocity in the uterine and ovarian arteries in premenopausal women
1995
Ingår i: Ultrasound in Medicine and Biology. - 0301-5629. ; 21:3, s. 313-319
Tidskriftsartikel (refereegranskat) abstract
Intra- and interobserver reproducibility of Doppler measurements of the pulsatility index (PI) and time-averaged maximum velocity (TAMXV) in the uterine and ovarian arteries were evaluated in examinations of healthy premenopausal women. Each woman underwent reproducibility measurements once in the late follicular phase and once in the midluteal phase. Intraobserver repeatability was assessed in examinations of 12 women, three replicate Doppler measurements being made by one observer in the same vessel. Interobserver agreement was assessed by comparing the results of Doppler measurements made by two investigators in 11 women. The intraclass correlation coefficient (Intra-CC) was 0.78 for the TAMXV in the dominant uterine artery in the follicular phase and 0.82 for the PI in the wall of the dominant follicle. For all other measurements the Intra-CC was < 0.75, indicating poor reproducibility. The interclass correlation coefficient (Inter-CC) was > 0.75 (0.79 to 0.88) for the PI and TAMXV in the dominant uterine artery in the follicular phase and for the PI of both uterine arteries in the luteal phase. For all other measurements the Inter-CC was < 0.75.
4.
Sladkevicius, Povilas, et al.
(författare)
Transvaginal Doppler examination for the differential diagnosis of solid pelvic tumors
1995
Ingår i: Journal of Ultrasound in Medicine. - 1550-9613. ; 14:5, s. 377-5380
Tidskriftsartikel (refereegranskat) abstract
To evaluate the ability of transvaginal Doppler examination to discriminate between different types of solid pelvic tumors, 55 women scheduled for laparotomy because of a solid pelvic mass underwent transvaginal sonographic examination, including color and spectral Doppler techniques. Arteries in the wall and core of each mass were examined. The histological diagnoses were as follows: uterine myoma (n = 28), malignant ovarian tumor (n = 19), and benign ovarian tumor (n = 8). Pulsatility index values tended to be highest in the malignant ovarian tumors, albeit with considerable overlap with respect to the other tumor types. The respective median pulsatility index values for arteries in the wall and core of the malignant ovarian tumors were 0.93 and 0.87, versus 0.65 and 0.51 in the benign ovarian tumors and 0.80 and 0.67 in the myomas. Time-averaged maximum velocity did not differ significantly among the three types of tumor. We conclude that Doppler measurement of blood flow velocity in tumor arteries does not add substantial information to the differential diagnosis between myomas and benign or malignant solid ovarian tumors.
5.
Sladkevicius, Povilas, et al.
(författare)
Transvaginal gray-scale and Doppler ultrasound examinations of the uterus and ovaries in healthy postmenopausal women
1995
Ingår i: Ultrasound in Obstetrics & Gynecology. - : Wiley. - 1469-0705 .- 0960-7692. ; 6:2, s. 81-90
Tidskriftsartikel (refereegranskat) abstract
The aim of this study was to elicit reference data representative of normal findings at transvaginal gray-scale and Doppler ultrasound examination of the uterus and ovaries in postmenopausal women. A total of 144 asymptomatic postmenopausal women with normal findings at clinical gynecological examination were included in the study. They underwent transvaginal sonography including Doppler measurements of blood flow velocity in the uterine and ovarian arteries. Ninety-eight (68%) women had a normal uterus and normal or non-visible ovaries at ultrasound examination, 23 (16%) had small uterine myomas but normal or non-visible adnexa, 19 (13%) had small adnexal cysts but a normal uterus, and four (3%) had both small myomas and small adnexal cysts. The median time-averaged maximum velocity (TAMXV) and pulsatility index (PI) values for the right and left uterine artery of normal uteri (n = 117) were 10.4 cm/s (range 2.2-43.0) and 10.6 cm/s (2.9-30.8), and 2.33 (0.97-5.13) and 2.35 (0.98-4.58), respectively. Median volumes of the normal right (n = 93) and left ovaries (n = 90) were 1.3 cm3 (0.4-3.7) and 1.2 cm3 (0.4-3.0), respectively, and median TAMXV and PI values for the stromal arteries in the normal right (n = 53) and left ovaries (n = 54) were 2.1 cm/s (1.3-4.6) and 2.3 cm/s (1.1-7.3), and 1.31 (0.65-2.61) and 1.26 (0.63-1.85), respectively. Our results provide a basis for gray-scale and Doppler ultrasound studies of pathological conditions in the female pelvis after the menopause.
6.
7.
Valentin, Lil
(författare)
Pattern recognition of pelvic masses by gray-scale ultrasound imaging: the contribution of Doppler ultrasound
1999
Ingår i: Ultrasound in Obstetrics & Gynecology. - : Wiley. - 1469-0705 .- 0960-7692. ; 14:5, s. 338-347
Tidskriftsartikel (refereegranskat) abstract
OBJECTIVE: To determine the extent to which Doppler ultrasound examination contributes to a correct specific diagnosis of a pelvic mass when the preliminary diagnosis is based on subjective evaluation of the gray-scale ultrasound image (pattern recognition). METHODS: In 173 consecutive cases, women scheduled for surgery because of a pelvic mass judged clinically to be of adnexal origin underwent preoperative gray-scale and color Doppler ultrasound examination. On the basis of subjective evaluation of the gray-scale ultrasound image, the ultrasound examiner classified each tumor as probably benign or malignant. If possible, a specific diagnosis was made, e.g. 'endometriosis' or 'dermoid cyst'. The confidence with which the diagnosis was made was rated subjectively on a visual analog scale. The diagnosis based on gray-scale imaging was re-evaluated after color Doppler examination, the diagnostic confidence after Doppler examination also being rated on a visual analog scale. 'Malignancy' was not considered a specific diagnosis. RESULTS: Pattern recognition of the gray-scale ultrasound image resulted in no unequivocal specific diagnosis in 51% (88/173) of cases, a correct specific diagnosis in 42% (72/173) and an incorrect specific diagnosis in 7% (13/173). Doppler examination added to a correct specific diagnosis in only 5% (8/173) of cases, either by changing an incorrect specific diagnosis to a (more) correct one (five tumors), or by increasing the confidence with which a correct specific diagnosis was made (three tumors). Doppler examination was misleading in one tumor. CONCLUSION: By using pattern recognition of the gray-scale ultrasound image, a correct specific diagnosis can be made in almost half of adnexal tumors scheduled for surgery. Subjective assessment of the color content of the tumor scan contributed little to the specific diagnosis of pelvic tumors.
8.
Valentin, Lil
(författare)
Prospective cross-validation of Doppler ultrasound examination and gray-scale ultrasound imaging for discrimination of benign and malignant pelvic masses
1999
Ingår i: Ultrasound in Obstetrics & Gynecology. - : Wiley. - 1469-0705 .- 0960-7692. ; 14:4, s. 273-283
Tidskriftsartikel (refereegranskat) abstract
OBJECTIVE: To cross-validate, prospectively, the diagnostic performance of established ultrasound methods for discrimination of benign and malignant pelvic masses. METHODS: A total of 173 consecutive women with a pelvic mass judged clinically to be of adnexal origin underwent preoperative ultrasound examination including color and spectral Doppler techniques. A total of 149 tumors were benign, and 24 were malignant. The sensitivity and false-positive rate with regard to malignancy were calculated for the following methods, using cut-off values recommended in previous publications: Lerner score; ultrasound morphology, i.e. tumors without solid components being classified as benign and tumors with solid components as malignant; tumor color score; pulsatility index; resistance index; time-averaged maximum velocity; peak systolic velocity; the combined use of ultrasound morphology and tumor color score and the combined use of ultrasound morphology and peak systolic velocity. Sensitivity and false-positive rate were also calculated for subjective evaluation of the gray-scale ultrasound image and for subjective evaluation of the gray-scale ultrasound image supplemented with subjective evaluation of color Doppler ultrasound examination. The confidence with which the diagnosis was made, based on subjective evaluation, was rated on a visual analog scale. RESULTS: Subjective evaluation of the gray-scale ultrasound image was by far the best method for distinguishing benign from malignant tumors (sensitivity 88%, false-positive rate 4%), followed in descending order by subjective evaluation of the gray-scale ultrasound image supplemented with color Doppler examination, the Lerner score and the time-averaged maximum velocity. Adding Doppler examination to subjective evaluation of the gray-scale image did not increase the number of correct diagnoses, but it increased the confidence with which a correct diagnosis was made in 14% of tumors. In 11 tumors (6% of the series as a whole), the addition of Doppler examination changed the diagnosis based on subjective evaluation of the gray-scale ultrasound image from an incorrect (n = 1) or uncertain (n = 10) diagnosis to a correct and confident diagnosis. CONCLUSION: In experienced hands, subjective evaluation of the gray-scale ultrasound image is the best ultrasound method for discriminating between benign and malignant adnexal masses. The main advantage of adding Doppler examination to subjective evaluation of the gray-scale image is an increase in the confidence with which a correct diagnosis is made.
