The latest medical research on Radiology

The research magnet gathers the latest research from around the web, based on your specialty area. Below you will find a sample of some of the most recent articles from reputable medical journals about radiology gathered by our medical AI research bot.

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Twin reversed arterial perfusion (TRAP): first-trimester intervention.

Ultrasound in Obstetrics and Gynecology

The aim of this study is to report the outcome of monochorionic twins with TRAP after interstitial laser therapy in the first trimester.

This is a retrospective cohort study of all consecutive cases of TRAP that underwent interstitial laser ≤ 14 + 3 weeks. Interstitial laser treatment was performed with Nd-YAG laser under sonographic control. Hospital records were reviewed to ascertain perinatal survival and morbidity.

Twelve monochorionic twin pregnancies underwent interstitial laser of the umbilical artery at a median age of 13+5 (IQR, 13+4-14+0) weeks. In all cases, we succeeded to interrupt the TRAP. There were no procedure related complications during or within 48 h after the procedure. One (8.3%) case was followed by intrauterine death of the pump twin two weeks after the intervention. All other cases (91.7%) resulted in live births at a median gestational age of 39+6 (IQR, 37+1-41+2) weeks and a median birth weight of 3370 (IQR, 2980-3480)g. There was no neonatal mortality or serious morbidity.

Our results support first-trimester interstitial laser therapy resulting in 92% live births. The results of a randomized controlled trial are yet to be awaited. This article is protected by copyright. All rights reserved.

Impact of Hypertension and Preeclampsia Intervention Trial At Near Term-I (HYPITAT-I) on obstetric management and outcome in The Netherlands.

Ultrasound in Obstetrics and Gynecology

The Hypertension and Preeclampsia Intervention Trial At near Term-I (HYPITAT-I) randomized controlled trial showed that, in women with gestational hypertension or mild pre-eclampsia at term, induction of labor, compared with expectant management, was associated with improved maternal outcome without compromising neonatal outcome. The aim of the current study was to evaluate the impact of these findings on obstetric management and maternal and perinatal outcomes in The Netherlands.

We retrieved data for the period 2000-2014 from the Dutch National Perinatal Registry, including 143 749 women with gestational hypertension or pre-eclampsia and a singleton fetus in cephalic presentation, delivered between 36 + 0 and 40 + 6 weeks of gestation (hypertensive disorder of pregnancy (HDP) group). Pregnant women without HDP were used as the reference group (n = 1 649 510). The HYPITAT-I trial was conducted between 2005 and 2008. To study the impact of HYPITAT-I, we compared rate of induction of labor, mode of delivery and maternal and perinatal outcomes in the periods before (2000-2005) and after (2008-2014) the trial. We also differentiated between hospitals that participated in HYPITAT-I and those that did not.

In the HDP group, the rate of induction of labor increased from 51.1% before the HYPITAT-I trial to 64.2% after it (relative risk (RR), 1.26; 95% CI, 1.24-1.27). Maternal mortality decreased from 0.022% before the trial to 0.004% after it (RR, 0.20; 95% CI, 0.06-0.70) and perinatal death decreased from 0.49% to 0.27% (RR, 0.54; 95% CI, 0.45-0.65), which was attributable mostly to a decrease in fetal death. Both the increase in induction rate and the reduction in hypertensive complications were more pronounced in hospitals that participated in the HYPITAT-I trial than in those that did not. Following HYPITAT-I, the rate of induction of labor also increased (by 4.6 percentage points) in the reference group; however, the relative increase in the HDP group (13.1 percentage points) was significantly greater (P < 0.001 for the interaction). The reduction in maternal and perinatal deaths did not differ significantly between the HDP and reference groups. There was a decreased incidence of placental abruption in both HDP and reference groups, which was significantly greater in the HDP than in the reference group (P < 0.001 for the interaction). There was also an increased incidence of emergency Cesarean section in both HDP and reference groups; however, this change was significantly greater in the reference than in the HDP group (P < 0.001 for the interaction).

Following the HYPITAT-I trial, there was a higher rate of induction of labor and improved obstetric outcome in term pregnancies complicated by HDP in The Netherlands. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Intracervical lakes as a sonographic marker of placenta accreta spectrum (PAS) in patients with previa and low-lying placenta.

Ultrasound in Obstetrics and Gynecology

Prenatal diagnosis of Placenta Accreta Spectrum (PAS) has been associated with reduced maternal morbidity. The introduction of new imaging signs is crucial in identifying women affected by this condition. The aim of our study is to evaluate the diagnostic accuracy of a new ultrasound sign, which it has been named "intracervical lakes", in predicting presence and outcome of PAS disorders.

retrospective multicentric study conducted in three Italian tertiary units from January 2015 to September 2018 including all women with placenta previa. The primary aim was to explore the diagnostic accuracy of intracervical lakes in detecting the presence and the depth of PAS disorders. The secondary aim was to explore the accuracy of this sign in predicting the following clinical outcomes: total estimated blood loss; antepartum bleeding; post-partum haemorrhage at the time of Caesarean Section; need for Caesarean hysterectomy. Diagnostic accuracy was assessed computing summary estimates of sensitivity, specificity, positive and negative predictive values (PPV and NPV), positive and negative likelihood ratios (LR+ and LR-), and diagnostic odds ratios (DOR).

332 women were included in the analysis with a median maternal age of 33.0 (29.0-27.0). Intracervical lakes were noted in 15.1% of overall patients with placenta previa. At logistic regression analysis, intracervical lakes were independently associated with major post-partum haemorrhage (OR 3.3; 95% CI 1.6-6.5; p<.001), hysterectomy (OR 7.0; 95% CI 2.1-23.9; p<.001), placenta percreta (OR 2.8; 95%CI 1.3-5.8; p<.01). Compared to the group with placenta previa without ultrasound signs of accretism, the association of at least one "typical" sign and intracervical lakes had an OR of 217.2 (95% CI 27.7-1703.4; p<.001) for placenta percreta and of 687.4 (95% CI 121.4-3893.0; p<.001) for Caesarean hysterectomy.

Intracervical lakes may represent a marker of deep villus invasiveness in women with suspected PAS at antenatal sonography and anticipate the occurrence of severe maternal morbidity. This article is protected by copyright. All rights reserved.

Early delivery in fetal gastroschisis: a randomized controlled trial of elective 34-week delivery vs routine obstetrical care.

Ultrasound in Obstetrics and Gynecology

We compared outcomes of elective late preterm delivery at 34 weeks (ED) with routine obstetric care (RC) in babies with gastroschisis.

Between May 2013 and September 2015, all women with a sonographically diagnosed gastroschisis referred to a single tertiary center before 34 weeks gestation were invited to participate in this study. Eligible patients were randomized to ED versus RC. The primary outcome measure was duration on total parenteral nutrition (TPN). Secondary outcomes were time to closure and length of stay. Outcome variables were compared using appropriate statistical methods. Analysis was based on intention-to-treat.

Eighty-four percent (21/25; 95% CI 63.9-95.5%) of eligible women were randomized; 10 to elective late preterm delivery and 11 to routine obstetric care. The trial was stopped at the first interim analysis after 21 of 86 planned patients were enrolled (24.4%, 95% CI 15.8-34.9%) for both patient safety concerns and for futility. The median gestational age at delivery was 34.3 weeks [34, 36] in the ED group and 36.7 [27, 38] in the RC group. Neonates of women who underwent elective preterm delivery had no difference in the primary outcome of duration on TPN and secondary outcomes of time to closure of gastroschisis and length of stay, but were significantly more likely to experience late-onset sepsis (Duration on TPN: ED 54 [17, 248], RC: 21 [9, 465], P = 0.08; Time to Closure: ED 7 [0, 15], RC 5 [0, 8] days, P = 0.28; Length of Stay: ED 70.5 [22, 137], RC: 31 [19, 186], P = 0.15; Neonatal Sepsis: ED 40%; 95% CI 12.2-73.8%, RC: 0%, P = 0.03) CONCLUSION: This study demonstrates no benefit of elective late preterm delivery of fetuses with gastroschisis when postnatal gastroschisis management is similar to that used in routine care. Rather, the data suggest that elective preterm delivery is detrimental to infants with gastroschisis. This article is protected by copyright. All rights reserved.

Impact of the new definition of pre-eclampsia on the incidence and performance of first-trimester screening for the disease.

Ultrasound in Obstetrics and Gynecology

The traditional definition of preeclampsia (PE) is based on the development of hypertension and proteinuria. This has recently been revised to include cases without proteinuria but with evidence of renal, hepatic or hematological dysfunction.

To examine the impact of the new definition of PE on first, the incidence and severity of the disease, and second, the performance of the competing risks model for first-trimester assessment of risk for PE.

This was a retrospective study of 66,964 singleton pregnancies that were classified as PE, gestational hypertension (GH) or no PE or GH according to the traditional criteria of the International Society for the Study of Hypertension in Pregnancy (ISSHP), which defines PE by the presence of both hypertension and proteinuria. We reviewed the records of GH and those cases with high creatinine or liver enzymes or low platelet count were reclassified as PE according to the new criteria of ISSHP (ISSHP-new) and the new criteria of the American College of Obstetricians and Gynecologists (ACOG). The groups of PE according to traditional criteria and new criteria were compared for first, the gestational age at delivery, birthweight percentile and incidence of SGA neonates with birthweight <10th percentile and perinatal death, and second, the predictive performance for preterm-PE of the competing risks model based on a combination of maternal risk factors, uterine artery pulsatility index (UtA-PI), mean arterial pressure (MAP) and serum placental growth factor (PLGF) at 11-13 weeks' gestation (triple test).

According to ISSHP-old 1,870 (2.8%) cases had PE, 2,182 (3.3%) had GH and 62,912 (94.0%) had no PE or GH. The incidence of PE according to ACOG was 3.0% (2,029 / 66,964) and ISSHP-new was 3.4% (2,301 / 66,964). The median gestational age at delivery for PE according to ISSHP-old (38.4 weeks) was lower than in the extra cases of PE according to AJOG (difference 1.3 weeks, 95% CI 0.71-1.71) and extra cases of PE according to ISSHP-new (difference 1.5 weeks, 95% CI 1.29-1.71). The incidence of SGA neonates in the cases of PE according to ISSHP-old (33.34%) was higher than in the extra cases of PE according to AJOG (relative risk 0.57%, 95% CI 0.42- 0.79) and extra cases of PE according to ISSHP-new (relative risk 0.52%, 95% CI 0.42- 0.65). In first-trimester screening for preterm-PE by the triple test, the detection rate, at 10% false positive rate, was 75.9%, (95% CI 70.8-80.6) for PE ISSHP-old, 74.3% (69.2-79.0) for PE AJOG and 74.0% (68.9-78.6) for PE ISSHP-new.

The new definitions of PE resulted in first, an increase of pregnancies classified as PE but the additional cases had milder disease, and second, a non-significant decrease in the performance of first-trimester screening for PE. This article is protected by copyright. All rights reserved.

From first-trimester screening to risk stratification of evolving pre-eclampsia in the second and third trimesters of pregnancy: a comprehensive approach.

Ultrasound in Obstetrics and Gynecology

Preeclampsia and associated hypertensive disorders of pregnancy represent a leading cause of global maternal and neonatal morbidity and mortality. ...

Sex-specific reference ranges of cerebroplacental and umbilicocerebral ratios: A longitudinal study.

Ultrasound in Obstetrics and Gynecology

The ratio of middle cerebral artery (MCA) pulsatility index (PI) to umbilical artery (UA) PI, i.e. cerebro-placental ratio (CPR), has been suggested as a measure of fetal "brain sparing" phenomenon reflecting redistribution of fetal cardiac output as a response to placental insufficiency. Observational studies have shown that low CPR values predict increased risk of adverse perinatal outcomes although evidence from randomized clinical trials is lacking. The inverse ratio, i.e. umbilico-cerebral ratio (UCR), is preferred by some as it increases with increasing degree of fetal compromise. Monitoring fetal wellbeing requires serial assessment, and for this purpose, appropriate reference values should be based on data from longitudinal studies. However, longitudinal reference ranges for the UCR have not been established. Furthermore, the sex of the fetus influences its growth velocity, cord properties, in utero circadian rhythm, behavioral states and placental function, but whether gestational age-dependent changes in CPR or UCR differ between male and female fetuses has not been studied. Thus, our objective was to investigate sex-specific, gestational age-associated serial changes in CPR and UCR during the second half of pregnancy and establish longitudinal reference ranges.

This was a dual-center prospective longitudinal study of singleton low risk pregnancies. Doppler blood flow velocity waveforms were obtained serially from the UA and MCA during 19-41 weeks of gestation, and PIs were determined. CPR and UCR were calculated as the ratios, MCA PI/ UA PI and UA PI/ MCA PI, respectively. The course and outcome of pregnancies was recorded. Sex of the fetus was determined after delivery. Reference intervals were constructed using multilevel modelling and gestational age-specific Z-scores of male and female fetuses were compared.

Of a total of 299 pregnancies enrolled, 284 women and their fetuses (148 male and 136 female) were included in the final analysis, and 979 paired measurements of UA and MCA PIs were used to construct sex-specific longitudinal reference intervals. Both CPR and UCR had U-shaped curves of development during pregnancy, but with opposite directions. There was a small but significant (P=0.007) difference in z-scores of CPR and UCR between male and female fetuses throughout the second half of pregnancy.

We have established longitudinal reference ranges for CPR and UCR suitable for serial monitoring with possibilities to refine the assessment by fetal sex-specific ranges and the conditioning by a previous measurement. The clinical significance of such refinements needs further evaluation. This article is protected by copyright. All rights reserved.

The IDEAL study: MRI for suspected deep endometriosis assessment prior to laparoscopy is equally reliable as radiological imaging as a complement to transvaginal ultrasonography.

Ultrasound in Obstetrics and Gynecology

this prospective observational study compared the value of magnetic resonance imaging (MRI) complementary to transvaginal ultrasonography (TV-US) to our standard preoperative assessment of patients with endometriosis referred for surgery in a tertiary care academic center. Based on the extent to which endometriosis affects reproductive organs, bowel, ureters, bladder or other abdominal organs, the surgery will be carried out by gynecologists only or by a multidisciplinary team involving abdominal surgeons and/or urologists.

In 74 women with clinically suspected deep endometriosis (DE) the standard preoperative imaging, i.e. an expert transvaginal ultrasonography (TV-US), complemented by an intravenous urography (IVU) for the evaluation of the ureters, and a double contrast barium enema (DCBE) for the evaluation of the rectum, sigmoid and caecum was compared with an expert TV-US complemented by a 'one-stop' abdominal and pelvic magnetic resonance imaging (MRI). The findings of the laparoscopy were the reference standard to provide an answer to the question if a 'one-stop' abdominal/pelvic MRI is equally reliable as our standard radiological imaging as a complement to transvaginal ultrasonography for preoperative triaging of patients with suspected urological and intestinal involvement by DE in tertiary care centers.

The standard preoperative imaging as well as the combined findings of the TV-US and the MRI allowed a correct stratification for a monodisciplinary approach by gynecologists or a multidisciplinary approach in 90.5% of the patients. Both TV-US and DCBE underestimated the severity of the rectal involvement in 2.7%, whereas TV-US and/or DCBE overestimated it in 6.8% of the patients.

In conclusion, complementary to an expert transvaginal ultrasound (TV-US) a 'one-stop' magnetic resonance imaging (MRI) predicts the intra-operative findings equally well as the standard radiological imaging (IVU and DCBE) in patients referred for endometriosis surgery in a tertiary care academic center. This article is protected by copyright. All rights reserved.

The natural history of pregnancy-related enhanced myometrial vascularity following miscarriage.

Ultrasound in Obstetrics and Gynecology

Our primary aim was to report the incidence of enhanced myometrial vascularity (EMV) in consecutive women following first trimester miscarriage who attended our early pregnancy assessment unit. We further aimed to evaluate the clinical presentation, and complications associated with the condition.

A prospective cohort study conducted in a London teaching hospital between June 2015 and June 2018. Consecutive patients with an observation of EMV by transvaginal ultrasonography (TVS) were included. The diagnosis was made following the subjective identification of EMV using color Doppler ultrasonography and a peak systolic velocity (PSV) ≥20cm/sec within the collection of vessels. Women were followed up with repeat scans every 14 days. Management was expectant unless intervention was indicated because of excessive or prolonged bleeding, the persistent presence of retained tissue in the endometrial cavity or patient choice. The final clinical outcome was recorded. Time to resolution was defined as the date of EMV detection until resolution was observed. The time to cessation of symptoms was also documented.

Forty patients were diagnosed with EMV during the study period following miscarriage and included in the study. There were 2627 first trimester losses in the department during this study period, hence the incidence of EMV following miscarriage was 1.52%. All cases were associated with ultrasound evidence of retained products of conception (RPOC) at presentation (mean dimensions 22x20x20mm). Thirty-one patients initially opted for expectant management, of which 18 were successful, five were lost to follow up and eight subsequently had surgical evacuation due to patient wishes. No expectantly managed case required emergency intervention. Nine patients chose surgical evacuation as primary treatment. No strong correlation was seen between PSV and blood loss at surgery (PSV range 20-148cm/sec, median 47 cm/sec). The estimated blood loss in all surgically managed cases ranged from 20-300mL. Products of conception were confirmed in all cases sent for histological analysis. For cases successfully managed expectantly, the mean time to resolution was 49 days (range, 21-84). The cases initially surgically managed had a mean time to resolution of 10.6 days (range, 3-29).

Our study suggests EMV is an uncommon finding following miscarriage and associated with the presence of retained products of conception (confirmed histologically in all cases surgically managed). Expectant management is a safe option in our cohort, with minimal bleeding, although associated with protracted time to resolution. When patients opt for surgery the maximum blood loss was 300mls, but no patient required a blood transfusion or embolization. This article is protected by copyright. All rights reserved.

Effect of sildenafil on maternal hemodynamics in pregnancies complicated by severe early-onset fetal growth restriction: planned subgroup analysis from a multicenter randomized placebo-controlled double-blind trial.

Ultrasound in Obstetrics and Gynecology

Fetal growth restriction (FGR) is associated with maternal cardiovascular changes. Sildenafil, a phosphodiesterase type 5 inhibitor, potentiates the actions of nitric oxide and has been proposed to alter maternal hemodynamics, potentially improving placental perfusion. Recently, the Dutch trial was stopped prematurely due to excess neonatal mortality secondary to pulmonary hypertension. The main aim of this study was to investigate the effect of sildenafil on maternal hemodynamics in pregnancies with severe early-onset FGR.

In this UK multicenter, placebo-controlled trial, we randomly assigned 135 women with singleton pregnancies and severe early-onset FGR (defined as a combination of estimated fetal weight or abdominal circumference below the 10th centile and absent/reversed end diastolic flow in the umbilical artery on Doppler velocimetry diagnosed between 22+0 -29+6 weeks' gestation), to receive either sildenafil 25mg three times daily or placebo until 32+0 weeks' gestation or delivery. The maternal blood pressure (BP), heart rate (HR), augmentation index, pulse wave velocity (PWV), cardiac output, stroke volume (SV) and total peripheral resistance were recorded before, 1-2 hours after, and 48-72 hours post-randomization, and 24-48 hours postnatally. For continuous data, the analysis was performed using repeated measures ANOVA methods including terms for time, treatment allocation and their interaction.

Sildenafil increased maternal HR by 4bpm when compared to placebo [5bpm (95%CI: 1, 12) vs 1 (-5, 8); P=0.004] and reduced systolic BP by 1mmHg more than placebo [-4mmHg (-9, 1) vs -3mmHg (-8, 5); P=0.048]. Even after adjusting for maternal BP, sildenafil reduced aortic PWV by 0.6 m/sec more than placebo did [-0.90m/sec (-1.31, -0.51) vs -0.26 (-0.75, 0.59); P=0.001]. Sildenafil was associated with a non-significant decrease in the SV index [-5.5m/m2 /beat (-11, -0.5) vs 0 (-0.5, 4); P=0.056].

Sildenafil in a dose of 25 mg three times daily increases HR, reduces BP and reduces arterial stiffness in pregnancies complicated by FGR. These changes are modest, consistent with the anticipated vasodilatory effect and their clinical impact on the mother and baby, in both the short- and long-term, remains uncertain. This article is protected by copyright. All rights reserved.

Early and late selective fetal growth restriction in monochorionic diamniotic twin pregnancies: natural history and diagnostic criteria.

Ultrasound in Obstetrics and Gynecology

The aim of this study was to evaluate the natural history and outcome of selective fetal growth restriction (sFGR) in monochorionic diamniotic (MCDA) twin pregnancies, according to the gestational age at onset and the various reported diagnostic criteria, and to quantify the risk of superimposed twin-to-twin transfusion syndrome (TTTS).

This is a cohort study of MCDA twin pregnancies that had their routine antenatal care from the first trimester at St George's Hospital, London. These pregnancies had ultrasound scans every 2 weeks at 16-24 weeks, and then every 2-3 weeks until delivery. The diagnostic criteria for sFGR were EFW <10th centile of one twin with inter-twin discordance of ≥25%. We also applied other diagnostic criteria reported in a recent Delphi consensus. Pregnancies where the diagnosis of TTTS was made before diagnosing sFGR were not included in this analysis. Gratacós classification was applied (Type 1, 2 or 3). Pregnancy outcomes included miscarriage, intrauterine demise (IUD), neonatal death (NND) and admission to the neonatal unit (NNU). Comparisons between groups were carried out using Mann-Whitney or Chi-Square (or Fisher's exact) test for categorical variables.

The analysis included 287 MCDA twin pregnancies. The incidence of early (<24 weeks) sFGR was 4.9%, while that of late sFGR was 3.8%, according to ISUOG diagnostic criteria. When applying the various diagnostic criteria, the incidence of early sFGR varied from 1.7% to 9.1% and late sFGR from 1.1% to 5.9%. In early sFGR, the incidence of type I was 80.8%, type II 15.4%, and type III 3.8%. The corresponding figures in late sFGR were 94.4%, 5.6% and 0%, respectively. The incidence of superimposed TTTS was 26.9% in cases affected by early-onset sFGR and 5.5% in late-onset sFGR. When managed expectantly, the incidence of PND was 8.0% in early sFGR and 5.6% in late sFGR (p=0.661). Admission to NNU occurred in 61.0% (early) and 52.9% (late sFGR) (p=0.484).

Compared to late-onset sFGR in monochorionic twin pregnancies, early-onset sFGR is slightly more common and associated with a worse perinatal outcome. The incidence of type II and III is more common in early sFGR. The incidence also varies according to the diagnostic criteria used, which supports the use of standardized international diagnostic criteria. Superimposed TTTS is more common in early than late sFGR. This article is protected by copyright. All rights reserved.

Cervical pessary vs vaginal progesterone for the prevention of preterm birth in women with twin pregnancies and a short cervix: an economic analysis alongside a randomized controlled trial.

Ultrasound in Obstetrics and Gynecology

To compare the costs and effects of cervical pessary versus vaginal progesterone in women with twin pregnancies and a short cervix.

We performed an economic analysis alongside a randomised controlled trial that compared cervical pessary to vaginal progesterone in women with twin pregnancy and a cervical length <38 mm. Main outcome measure was morbidity-free survival neonate. Data on pregnancy outcomes, maternal morbidity and neonatal complications were collected prospectively from medical files; other additional information was obtained via patient telephonic questionnaires. The incremental cost-effectiveness ratio (ICER) was calculated as the incremental cost to achieve one extra morbidity-free survival neonate in the pessary group compared to progesterone group. Probabilistic sensitivity analysis (PSA) and a cost-effectiveness acceptability curve (CEAC) were also performed.

Between March 4th 2016 and June 3rd 2017, we screened 1,113 women with twin pregnancies, of whom 300 women fulfilled the inclusion criteria and gave informed consent. These women were randomly assigned to cervical pessary (n=150) or vaginal progesterone (n=150). The rate of morbidity-free survival neonate was significantly higher in the pessary group than that in the progesterone group (241 [81.4%] versus 219 [73.5%], relative risk [RR] 1.11, 95% confidence interval [CI] 1.02 to 1.21, p=0.02, respectively). The mean total cost per woman was 3,148 EUR in the pessary group versus 3,571 EUR in the progesterone group (mean difference -423 EUR, 95% CI -841.8 to -3.3, p=0.048). The cost per morbidity-free survival neonate was significantly lower in the pessary group than that in the progesterone group (2,492 vs. 2,639 EUR, absolute difference -147, 95% CI, -284 to 10; p=0.035).

In women with twin pregnancies and a short cervix, cervical pessary significantly improves the rate of morbidity-free survival neonate while reducing costs as compared to vaginal progesterone. This article is protected by copyright. All rights reserved.