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Precision of umbilical artery Doppler studies. Intraobserver, interobserver, and biologic variability of fetal Doppler velocimetry.

The use of Doppler ultrasound to study fetal blood flow has become commonplace, despite the lack of detailed evaluation of the testing tool for precision. In evaluation of 25 patients, no significant intraobserver differences were found between readings on an individual waveform, nor were there significant differences between different observers on individual waveforms. Temporally separated waveforms within a 30-minute window gave the greatest variation. A multi-way analysis of variance noted significant differences in this category only. This study confirmed the precision of measurements by a single observer and between observers. Only biological alterations over time displayed significant variability.

Analysis of Variance↗

[Diagnostic and prognostic value of the echo-Doppler and transcranial Doppler methods in the acute phase of ischemic ictus].

The ischaemic ictuses are a frequent pathology. For their annulling potentiality a quick etiopathogenetic diagnosis is necessary to institute a suitable therapy that limiting the extension of the cerebral damage. In this respect, it is fundamental the use of the duplex methods in real time together with doppler valuation of the neck vessels (carotid and vertebral) and of the intracranial big arteries. The direct observation of the endoluminal surface in the extracranial vessels and the valuation of the circulatory condition in the individual arterial districts explored give as important of haemodynamic information which, added to that obtained through a computerized axial tomography and the clinic, allows a correct diagnostic valuation with important effects on the therapy as well as a reliable prognostic formulation. Description of two clinical cases.

Acute Disease↗

Association of left ventricular filling parameters assessed by pulsed wave Doppler and color M-mode Doppler echocardiography with left ventricular pathology, pulmonary congestion, and left ventricular end-diastolic pressure.

Among 90 consecutive patients with various degrees of left ventricular (LV) dysfunction (normal patients, LV hypertrophy, LV ejection fraction <50%, and <30%), the mitral valve pulse-wave E/A ratio showed a characteristic U-shaped curve with increasing severity of LV dysfunction. In contrast, there was a significant progressive decrease in flow propagation velocity of the E-wave (Vp) and a significant increase in E/Vp values with increasing severity of LV dysfunction. The E/Vp ratio was the best predictor of pulmonary congestion, and in a subgroup of patients who underwent cardiac catheterization, it was the only significant predictor of LV end-diastolic pressure.

Adolescent↗

Power Doppler versus color Doppler imaging in renal allograft evaluation.

The purpose of this study was to evaluate the impact of PDS compared to conventional CDI in the followup of 72 renal allograft patients. Renal allograft vascularization, assessed by PDS and CDI, was scored from 0 to 4, where 0 was the cortical "blush" and 4 was residual central perfusion. These scores were correlated with the resistive index, serum creatinine levels, hematocrit, and, in 35 cases, biopsy results. PDS scores of renal perfusion were one grade lower than CDI scores in 59 of 72 patients and two grades lower in two of 72 patients. A statistically significant correlation was found between PDS scores and the RI (r2 = 0.6, P < 0.05). However, no significant correlation was found between PDS scores and creatinine levels or hematocrit values. PDS scores are not related to histologic findings in renal allograft dysfunction. Overall, five biopsy-related arteriovenous fistulas were detected, two of which were missed on the initial PDS examination. In conclusion, PDS provides more complete visualization of the renal allograft vessel tree than CDI. However, biopsy-related arteriovenous fistulas are better seen by CDI.

Biopsy↗

Effect of sample volume location on Doppler-derived transmitral inflow velocity values in 288 normal subjects 20 to 80 years old: an echocardiographic, two-dimensional color Doppler cooperative study.

The aims of the study were to evaluate in a population of 288 normal subjects 20 to 80 years old (1) the normal values of the indexes of the mitral flow velocity pattern measured either at the tips of the mitral leaflets or at the annulus; (2) whether there was a significant difference between the values obtained at the tips compared with those measured at the mitral annulus; (3) the correlation with aging between the indexes measured in the two different positions; and (4) whether certain physiological variables have different effects on diastolic function measured in the two different positions. The highest values were always measured at the tips of the mitral leaflets (p < 0.05); only atrial filling fraction, E acceleration time, and E deceleration velocity had higher values when measured at the level of the annulus (p < 0.05). The A-wave peak velocity had the same mean value when measured at both the tips and at the annulus. A significant difference in the correlation between parameters measured at the tips of the mitral leaflets with age and at the annulus (with age) was observed for the following parameters: (1) peak E velocity, E integral, total integral and E acceleration showed better correlation with age when measured at the annulus (p < 0.02); (2) peak A velocity and A integral showed better correlation with age when measured at the tips of the mitral leaflets (p < 0.001). Multivariate analysis showed that age was the variable that had the most influence on diastolic function parameters; heart rate had less influence on the diastolic function indexes.

Adult↗