Modification of the hand-held Vscan ultrasound and verification of its performance for transvaginal applications.

PURPOSE: The purpose of this work was to validate a new clinical obstetrics and gynecology (OB-GYN) application for a hand-held ultrasound (US) device. We modified the smallest hand-held device on the market and tested the system for transvaginal (TV) use. This device was originally conceived for abdominal scanning only. METHODS: The validation involved 80 successive patients examined by the same operator: 25 obstetric and 55 gynecologic cases. US examination was performed transvaginally with two US systems: the hand-held Vscan (General Electrics; GE Vingmed Ultrasound; Norway) for which an intravaginal gadget TTGP-2010® (Troyano transvaginal gadget probe) was designed, and the Voluson 730 Expert (multifrequency transvaginal ultrasound of 3-9MHz; GE Healthcare, Milwaukee, WI, USA). We performed the same measurements with both US systems in order to confirm whether or not their diagnostic capability was similar. Quantitative difference in measurements between the systems was assessed, as well as the overall diagnostic detection rate and suitability for telemedicine. RESULTS: Regarding lesion visibility with Vscan, optimal distance was 8-16cm depending on the examination type, and the total detection rate was 98.7%. The exception was an ovarian endometrioma, diagnosed as a follicular cyst using the hand-held device. Assessment of reproducibility in 180 measurements showed that the measurements obtained with Vscan were 0.3-0.4cm lower than those obtained with the high resolution US device (Voluson 730 Expert). Nevertheless, Pearson's correlation coefficient was high for biparietal diameter (0.72) and gynecological (GYN) (0.99) measurements, and for overall correlation (0.997). Image transport on USB and SD-flash cards proved convenient for telemedicine. CONCLUSIONS: A novel TV application of a hand-held US device is demonstrated for OB-GYN. Heart, abdominal and obstetrics presets of the Vscan together with color-Doppler enable a detection capability comparable to that of a high-definition US device. The lower values of the measurements obtained by the hand-held device (by 0.3-0.4cm) must be taken into account, although they have no effect on its diagnostic capability.

Anomalías del sistema urinario / Anomalies of the urinary system

Se realiza una descripción de las principales malformaciones del sistema nefrourológico: Agenesia renal, Ectopia renal, Riñón en herradura, Displasia renales, Hidronefrosis y Anomalías dilatadas con sus características de diagnóstico intraútero. (AU)

Valor de la ecografía en el manejo de la miomatosis uterina / Value of ultrasonography in the management of uterine myomatosis

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The influence of maternal erythrocyte deformability on fetal growth, gestational age and birthweight.

The increase in blood viscosity during pregnancy reduces maternal-fetal blood flow, which can lead to fetal hypoxia and acidosis. These factors have been related to a reduction in fetal growth and to premature births. We carried out a longitudinal study of 36 normal-term gestations at different stages of the pregnancy. We analyzed the erythocyte deformability, the intraerythocyte viscosity and the plasma viscosity in the mother, as well as the relation of these parameters to fetal growth (biparietral diameter (BPD) and length of the femur), birthweight, gestational age at birth and the Agpar score. The results obtained were as follows: from weeks 25 to 36 of pregnancy (30.9 (SD 2 weeks)) there occurs a significant increase in maternal erythocyte rigidity (p < 0.05) (despite the compensatory decrease in intracellular viscosity). This increase is very significantly related to the fetal biparietral diameter (r = -0.50, p < 0.01), the length of the fetal femur (r = -0.48, p < 0.02), gestational age at birth (r = -0.73, p < 0.0001, birthweight (r = -0.63, p < 0.001) and the Agpar score 5 minutes after birth (r = 0.67, p < 0.001). Our conclusions are that the reduction in erythocyte deformability (which we attribute to alterations in the fluidity or elasticity of its membrane) and the factors that increase the aggregation capacity of the red cells (modulators of blood viscosity and of blood flow in the placental intervillous space) are risk factors for reduced fetal growth, lower birthweight and lower gestational age at birth. By avoiding maternal hematocrit levels higher than 36% we could improve uteroplacental perfusion, fetal growth and perinatal results.