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J Kurmanavicius

Publications and source records attributed to J Kurmanavicius.

12 recordsLinked to original sources
PubMed2001

Reference values of fetal peak systolic blood flow velocity in the middle cerebral artery at 19-40 weeks of gestation.

OBJECTIVES: The objectives of this prospective study were (i) to establish new reference values of peak systolic blood flow velocity measurement in the fetal middle cerebral artery (MCA-PSV) following validated methodological guidelines and (ii) to develop a method to calculate Z-scores of MCA-PSV. PATIENTS AND METHODS: Cross-sectional data were obtained from 331 pregnant women between 19 and 40 weeks' gestation. Reference ranges for MCA-PSV were constructed and for each measurement linear regression models were fitted separately to the mean and standard deviations (SD) as a function of gestational age. An application to calculate Z-scores was developed. A comparison was made between the reference ranges produced in our study and those of a previous one. RESULTS: A new chart, table of centiles and regression equations of MCA-PSV are presented. Comparison of our reference ranges with ones produced in a previous study showed similar 5th centile values. However, the values for the 50th and 95th centiles between 19 and 28 gestational weeks were lower in our study. CONCLUSIONS: We have constructed reference ranges for MCA-PSV which, because they are derived from a larger number of examinations in the 15-20-week period and because the methodological flaws of the previously published study have been eliminated, we consider to be more accurate and therefore more useful for clinical practice.

Blood Flow Velocity↗
PubMed2000

Dandy-walker malformation: prenatal diagnosis and outcome.

Prenatal ultrasound identified Dandy-Walker malformation (DWM) in ten singleton pregnancies with concurrent central nervous system (CNS) anomalies and extra-CNS anomalies in eight cases. DWM was confirmed by postnatal magnetic resonance imaging (MRI) or pathological examination in nine cases. Karyotypes were normal in the seven infants tested. Postnatal neurological and developmental testing in the five survivors showed a spectrum of clinical outcome from minor defects to severe handicap. Postnatal investigation also disclosed additional CNS and extra-CNS findings not detected on ultrasound, as did autopsy in the other five infants. However, ultrasound diagnosis of DWM is accurate and is an indication for exhaustive screening for concurrent anomalies both within and outside the CNS and in chromosome structure and number, as the prognosis is heavily dependent on associated malformations and karyotype.

Adult↗
PubMed1999

Use of 3D ultrasound as a new approach to assess obstetrical trauma to the pelvic floor.

OBJECTIVE: To determine whether 3D ultrasound examination of pelvic floor anatomy after vaginal delivery allows detection of childbirth trauma. STUDY DESIGN: Pelvic floor anatomy was examined in 16 women during the puerperium with a 3D transrectal ultrasound probe. Images were acquired via the vaginal route for the assessment of anal morphology and the transrectal route to determine paravaginal fixation. Images of the anterior pelvic floor were calculated from the information stored in the volume block. Paravaginal defect is defined as a descent of the lateral vaginal wall below the suburethral vagina, whereas sphincter defects are characterised as thinning, or as gap formation of the anterior part of the internal anal sphincter. RESULTS: This new approach allowed the examination of a horizontal plane through the urethra and the periurethral tissue which is inaccessible with 2D ultrasound techniques. Morphology of the normal and traumatised anal sphincter could be demonstrated using reference planes perpendicular to the anal canal. CONCLUSIONS: Whereas in the past, defects of the vaginal attachment to the pelvic side wall could not be examined sonographically, 3D ultrasound can now be used to examine pelvic floor anatomy and to detect changes associated with trauma to the pelvic floor following vaginal delivery.

Fecal Incontinence↗
PubMed1999

Fetal ultrasound biometry: 1. Head reference values.

OBJECTIVE: To create reliable reference ranges and calculate Z scores for fetal head ultrasound biometry using a large sample size which is evenly distributed from 12 to 42 weeks of pregnancy. DESIGN: A prospective, cross-sectional study. SETTING: Obstetric clinics (outpatient and delivery units) at the University Hospital of Zurich. SAMPLE: The study data were obtained from 6557 pregnant women. METHODS: Only the first ultrasound examination between 12 and 42 weeks of each fetus with exactly established gestational age was used for analysis. No exclusions were made on the grounds of small-for-date birthweight, prematurity or other events several weeks after the examination. Separate regression models were fitted to estimate the mean and standard deviation at each gestational age for each parameter. RESULTS: A total of 6217 fetal head biparietal diameters and 5510 occipito-frontal diameters were measured. Both head circumference and cephalic index were derived in 5462 cases where both biparietal diameter and occipito-frontal diameter could be measured on the same fetus. The centile charts, tables and regression formulae for biparietal and occipito-frontal diameters, head circumference and cephalic index are presented. An application to calculate Z scores was developed using Excel (Microsoft Corporation, USA) and macros are presented in detail in the Figure 8 footnote. The comparison of our charts with those of the two most recent studies revealed almost no differences in biparietal diameter centiles. In one publication, occipito-frontal diameter charts, and in another, head circumference charts were different from the current study. CONCLUSIONS: We have presented centile charts, tables and regression formulae for fetal head ultrasound biometry derived from a large and minimally selected sample size in a carefully designed cross-sectional study. Complete tables and regression formulae to calculate reference ranges and Z scores are presented for use in computer-aided evaluation of fetal ultrasound biometry.

Adult↗
PubMed1999

Fetal ultrasound biometry: 2. Abdomen and femur length reference values.

OBJECTIVE: To create reliable reference ranges and calculate Z scores for fetal abdomen and femur ultrasound biometry using a large sample size which is evenly distributed from 12 to 42 weeks of pregnancy. DESIGN: A prospective, cross-sectional study. SETTING: Obstetric clinics (outpatient and delivery units) at the University Hospital of Zurich. SAMPLE: The study data were obtained from 6557 pregnant women. METHODS: Only the first ultrasound examination between 12 and 42 weeks of each fetus with certainly established gestational age was used for analysis. No exclusions were made on the grounds of small-for-date birthweight, prematurity or other events several weeks after the examination. Separate regression models were fitted to estimate the mean and standard deviation at each gestational age for each parameter. RESULTS: A total of 5807 mean abdominal diameters and abdominal circumferences were derived from fetal transverse and anterio-posterior fetal abdominal diameter measurements. Fetal femur length was measured in 5860 instances. The charts, tables and regression formulae of the biometrical measurements are presented. A comparison of our charts with others showed no significant difference. Only Merz's centiles for abdominal biometry were lower and for femur length higher than ours. An application to calculate Z scores was developed using Excel (Microsoft Corporation, USA); the macros are presented in detail in the Figure 6 footnote. CONCLUSIONS: We have presented centile charts, tables and formulae for fetal abdominal diameter and circumference and femur length derived from a large and minimally selected sample size in a carefully designed cross-sectional study. Complete tables and regression formulae to calculate reference ranges and Z scores are presented to use in computer-aided evaluation of fetal ultrasound biometry.

Abdomen↗
PubMed1998

Pulsatility index in the fetal anterior tibial artery during the second half of normal pregnancy.

The objective of this prospective study was to establish reference values for the pulsatility index in the fetal anterior tibial artery during the second half of pregnancy. Pulsed Doppler waveform analysis of 203 fetuses at 23-42 weeks of pregnancy was performed, each fetus being examined just once. There were neither fetal nor maternal complications detectable at the time of the examination. In the first 14 fetuses from which recordings were taken, Doppler examination was performed on both fetal legs in order to evaluate systematic differences between the right and left legs. Intraobserver variability was analyzed by repetition of the measurements by the same examiner in the first 130 cases. There was no difference between right and left tibial circulation. The repeatability coefficient, defined as the 95% range for the difference in two repeat measurements, was 1.08. The pulsatility index of the anterior tibial artery (50th centile) increased slightly from 3.29 at 23 weeks of pregnancy to 4.09 at 42 weeks. The 5th and 95th centiles were calculated, as was the 95% confidence interval of the 5th and 95th centiles. Examination of the fetal peripheral circulation during the second half of pregnancy is possible with a high degree of precision. Whether there are changes in peripheral arterial circulation in compromised fetuses remains to be evaluated.

Female↗
PubMed1997

Successful treatment of fetal megavesica in the first half of pregnancy.

OBJECTIVE: Our goal was to assess fetal kidney function in fetuses with megavesica diagnosed during the first half of pregnancy before treatment. STUDY DESIGN: In a prospective interventional study 9 fetuses with megavesica diagnosed during the first half of pregnancy underwent vesicocentesis. Fetal urine biochemical markers (urine electrolytes, osmolarity, and beta 2-microglobulins) were determined after diagnostic vesicocentesis of the fetal megavesica. RESULTS: Surprisingly, in four fetuses who underwent sampling at 13 to 18 postmenstrual weeks, vesicocentesis proved both diagnostic and therapeutic. Pregnancy proceeded with normal amniotic fluid volume, a normal-sized urinary bladder with normal dynamics, and normal postnatal renal function. A fifth fetus had trisomy 18. In three of the remaining four fetuses in whom sampling was performed at 16 to 20 postmenstrual weeks, biochemical markers indicated a poor prognosis. In the remaining fetus marginal results of biochemical studies prompted intrauterine treatment, but death from respiratory problems ensued after premature delivery at 31 weeks. CONCLUSIONS: Fetal megavesica in the first half of pregnancy is an indication for an immediate diagnostic vesicocentesis. This is the first report emphasizing early diagnosis of fetal megavesica with subsequent fetal vesicocentesis and demonstrating that this minimally invasive procedure can be life-saving if performed in early pregnancy.

Abdominal Muscles↗
PubMed1997

Reference resistance indices of the umbilical, fetal middle cerebral and uterine arteries at 24-42 weeks of gestation.

The objective of this cross-sectional study was to construct new reference ranges for Doppler flow velocity waveform resistance indices for the fetal umbilical artery, middle cerebral artery, placental and non-placental uterine arteries and the placentocerebral ratio in a large and minimally selected population attending a single clinic. Study design and data analysis adhered to a number of stringent and validated methodological recommendations derived both from the recent literature and from a review of earlier publications in this field. The final database comprised initial routine Doppler velocimetry at 24-42 weeks' gestation in 1675 pregnancies. Separate regression models were fitted to estimate the mean and standard deviation at each gestational age for each vessel. New charts, centile tables and regression equations are presented for the resistance indices of the fetal umbilical artery, middle cerebral artery, placental and non-placental uterine arteries and the mean of both uterine arteries and for the placentocerebral ratio.

Adult↗
PubMed1994

[Lateral pathologic flow in the uterine artery in the 3rd trimester of pregnancy and the fetal status].

From a total of 2,312 Doppler examinations made in 1992 at the Gynaecological Department of the University Clinic in Zürich in 34 patients in the 3rd trimester of pregnancy a lateralized pathological blood flow in the uterine artery on the non-placental side was found. As a control group the authors selected a group of 34 patients comparable as to age, gestation period, time when the Doppler examination was made and the type of delivery. The results of the investigation are not statistically significant in view of the low percentage incidence of lateralized pathology, however, it may be stated that the finding may be the first symptom of incipient foetal hypoxia.

Apgar Score↗
PubMed1993

[Apple-Macintosh compatible software for documentation, management and evaluation of ultrasound findings in obstetrics].

The advantage of using a computer to automate routine calculations and print out charts of the obstetrical ultrasound examination is obvious. This report describes a software designed to simplify the documentation and analysis of ultrasound data in obstetrics. The system is easy to use, even for persons with little computer knowledge. The programme was written in FoxBase+/Mac (Fox Software, Inc., USA). FoxBase+/Mac takes full advantage of the easy-to-learn, easy-to-use Macintosh interface and is also very fast. Another advantage of this software is that it can be used in teaching. Non-experienced examinators can double-check the correctness of their scanning planes by observing the ultrasound pictures with the markers indicating the right measurement sites and the lists of standard values of biometrical parameters for the corresponding gestational age on the screen. In routine obstetrical ultrasound examinations it takes less than 5 min to enter the foetal biometry data and print out reports. These reports are informative and easy to interpret.

Female↗
PubMed1992

Umbilical artery blood flow velocity waveforms in twin pregnancies.

To detect discordant fetal growth in twin pregnancies and assess a possible role for Doppler ultrasound measurements of blood flow velocity waveforms in umbilical arteries in such cases, 32 twin pregnancies were examined on 125 occasions. The last examination was within 14 days of delivery. There was postpartum death of one pair of twins with the twin transfusion syndrome. Birthweight was appropriate for gestational age in 15 twin pairs, both infants were small for gestational age (SGA) in 5, and one of the infants was SGA in 12 twin pairs. The correlation coefficient of RI difference at the last examination and percentage birth weight difference in twin pairs was 0.68. Cutoff points for the delta RI and weight difference were established. The sensitivity of delta RI (0.1) was 77.8%; specificity, 95.8%; positive predictive value, 87.5%; and negative predictive value, 92.0%.

Blood Flow Velocity↗