Obstetrics and GynecologyPrenatal screening, fetometry, gynecological ultrasound according to international standards.
Scar niche (isthmocele) is assessed by ultrasound with mandatory measurement of residual myometrium — the thickness of tissue between the defect and bladder wall. Available fragments …
Read →Retained products of conception (RPOC) are identified on ultrasound as an intra-cavitary mass within the uterus following delivery or abortion; the combination of grayscale imaging and …
Read →Decidualized endometrioma is an important diagnostic pitfall during pregnancy: under the influence of gestational hormones, papillary projections with vascularization develop within the endometrioma, mimicking malignancy and …
Read →According to the IDEA protocol, sliding sign is a dynamic transvaginal technique for assessing the mobility of the posterior uterine wall/cervix relative to the rectum. A …
Read →According to IOTA, endometrioma is a uni- or weakly multilocular cyst with homogeneous low-level echosignals ('ground-glass'), smooth wall, and no vascularized solid tissue on Doppler. Hemorrhagic …
Read →Hydrosalpinx on ultrasound is visualized as an elongated fluid-filled tubular structure with incomplete septa. Characteristic findings include the 'cogwheel sign' (small bulges <3 mm along the …
Read →For standardized ultrasound description of uterine fibroids, the FIGO classification (2011, PALM-COEIN) is used for node localization (types 0–8) and MUSA terminology (consensus, 2015) for describing …
Read →Endometrial polyp is often visualized as a localized echogenic or mixed-echogenicity lesion within the uterine cavity, sometimes with a feeding vessel. Submucosal leiomyoma, conversely, deforms the …
Read →Abdominal wall defects (AWD) complicate approximately 6–7 cases per 10,000 deliveries in the USA and are most commonly represented by gastroschisis or omphalocele (Ultrasound Obstet Gynecol, …
Read →Non-immune fetal hydrops (NIHF) is diagnosed on ultrasound when fluid accumulates in two or more fetal serous cavities, including skin edema, ascites, pleural and/or pericardial effusion. …
Read →For standardized assessment of fetal urinary tract dilation, a multidisciplinary UTD consensus (Nguyen HT et al., 2014) is applied, referenced in current ISUOG, ACR–ACOG–AIUM–SMFM–SRU guidelines. It …
Read →According to the updated ISUOG 2023 guidelines for ultrasound performance at 11–14 weeks, first trimester screening allows assessment of basic fetal anatomy, determination of gestational age …
Read →The diagnosis of cesarean scar pregnancy (CSP) is justified when four ultrasound criteria (ISUOG, 2024) are fulfilled: empty uterine cavity and cervical canal without gestational sac; …
Read →MCA-PSV is the primary non-invasive method for detecting fetal anemia: according to SMFM, it has replaced routine assessment of amniotic fluid bilirubin. A threshold value of …
Read →First trimester preeclampsia screening using the Fetal Medicine Foundation (FMF) algorithm is performed at 11–13 weeks and combines maternal factors, mean arterial pressure (MAP), uterine artery …
Read →Fetal ventriculomegaly is diagnosed when the transverse measurement of the lateral ventricle atrium is >10 mm. Measurement is performed at the level of the glomus of …
Read →Differential ultrasound diagnosis of cystic anomalies of the posterior fossa (Dandywalker malformation, Blake's pouch cyst) relies on assessment of the cerebellar vermis, position of the choroid …
Read →The 'lemon sign' and 'banana sign' are intracranial ultrasound markers of open spina bifida assessed during routine screening. Their diagnostic value was demonstrated in the landmark …
Read →Soft markers of aneuploidy are ultrasound findings in the second trimester associated with chromosomal pathology. In the era of NIPT, their independent role is being reconsidered: …
Read →When assessing placental location, the shortest distance from the lower edge of the placenta to the internal cervical os is measured. According to ISUOG (2024), at …
Read →TAPS in monochorionic twin pregnancy is diagnosed when donor MCA-PSV >1.5 MoM and recipient MCA-PSV <1.0 MoM, or when the inter-twin difference (delta) >0.5 MoM. Doppler …
Read →The Gratacos classification divides selective FGR in monochorionic twin pregnancy into three types based on umbilical artery blood flow patterns in the smaller fetus. It was …
Read →According to ISUOG recommendations (2024), amniotic fluid volume is assessed subjectively ('normal'/'decreased'/'increased') or semi-quantitatively. AFI is preferable for polyhydramnios assessment, whereas maximum vertical pocket (DVP/SDP) is …
Read →In dichorionic diamniotic (DCDA) twin pregnancy, the fetuses are separated by a thick layer of fused chorionic membranes with two thin amniotic layers—forming a "complete lambda" …
Read →Twin-to-twin transfusion syndrome (TTTS) in monochorionic pregnancy is staged according to the Quintero system based on ultrasound findings: diagnosis is established when the maximum vertical pocket …
Read →Key sonographic markers of the placenta accreta spectrum (PAS) include low anterior placenta or placenta previa overlying a cesarean scar, multiple irregular placental lacunae with architectural …
Read →Vasa previa is diagnosed on transvaginal ultrasound with color Doppler imaging: unprotected fetal vessels crossing the membranes over the internal cervical os or within <20 mm …
Read →According to the ISUOG/IDEA 2024 consensus, expert transvaginal ultrasound (TV-US) is the first-line method for non-invasive diagnosis and preoperative mapping of pelvic deep endometriosis. MRI is …
Read →The IOTA 2026 update is the first major revision of terms for describing adnexal masses since 2000. In the practical protocol, key elements remain the measurement …
Read →In O-RADS US v2022, the risk of malignancy is coded as follows: O-RADS 2 — less than 1%, O-RADS 3 — from 1% to less than …
Read →According to IETA/ISUOG 2026, the endometrium is measured in the mid-sagittal plane as the maximum anteroposterior dimension of the 'double layer' in mm; when intracavitary fluid …
Read →The revised MUSA 2022 definitions divide ultrasound signs of adenomyosis into direct and indirect. The key diagnostic rule: at least one direct sign is required for …
Read →The IDEA 2025 addendum standardizes for the first time the transvaginal sonographic assessment of superficial, or peritoneal, endometriosis; the document is published in Ultrasound in Obstetrics …
Read →According to ISUOG 2025, chorionicity and amnionicity should be established in the first trimester, optimally during the 11–13+6 week scan. Uncomplicated monochorionic twins are monitored with …
Read →According to ISUOG 2024, third-trimester ultrasound is performed from 28+0 weeks until delivery: the mandatory minimum includes fetal presentation, biometry with EFW calculation, placental localization, assessment …
Read →According to AIUM 2024, the first trimester ends at 13+6 weeks, the second lasts from 14+0 to 27+6 weeks, and the third begins at 28+0 weeks. …
Read →According to SMFM 2024, a short cervix in an asymptomatic patient with a singleton pregnancy and no history of spontaneous preterm birth is diagnosed with a …
Read →The FMF 2025 model for 19–24 weeks is based on a cohort of 134,443 singleton pregnancies and assesses the risk of preeclampsia with delivery before 28, …
Read →ISUOG has released its first specialized document on POCUS in obstetrics and gynecology: online — November 2025, publication in UOG — 2026;67:116-127. The main principle: bedside …
Read →The selection of an ultrasound diagnostic course in obstetrics and gynecology relies on the training structure (undergraduate and subsequent levels), simulation technologies (VR simulators), and skill …
Read →Ectopic pregnancy remains a key urgent situation in early imaging: the narrow diagnostic window and high clinical risks require precise classification. Pregnancy of unknown location (PUL) …
Read →The IOTA/ISUOG 2026 consensus updates the basic language for describing adnexal tumors: the mass should be measured in three mutually perpendicular dimensions, separately noting the largest …
Read →According to the updated ISUOG 2025 guidelines, chorionicity should be determined at 11+0–13+6 weeks, and monochorionic diamniotic twins should be monitored by ultrasound every 2 weeks …
Read →According to ISUOG 2025, selective IUGR in twins should be suspected with significant discordance in estimated fetal weight; the threshold requiring specialized assessment is ≥25%, calculated …
Read →According to ISUOG 2024, the third trimester begins at 28+0 weeks, and routine ultrasound should be standardized: viability, presentation, 4 basic biometrics, EFW calculation, amniotic fluid, …
Read →According to the ISUOG 2025 consensus, in hypertensive disorders of pregnancy and FGR, maternal hemodynamics should be described not only by blood pressure but by a …
Read →According to the ISUOG 2026 consensus, the endometrium is primarily assessed transvaginally in the mid-sagittal plane; thickness is the double layer of the endometrium in mm …
Read →For accurate O-RADS US, the protocol must provide the morphology of the lesion in three orthogonal dimensions and a reproducible assessment of blood flow with a …
Read →According to the <a href="https://www.isuog.org/clinical-resources/isuog-guidelines/practice-guidelines-english.html">ISUOG 2025</a>, gynecological PoCUS for acute pelvic pain should address a limited set of clinical questions at the patient's bedside: is there …
Read →Prenatal ultrasound screening is structured into three periods, corresponding to international ISUOG protocols: the 11–14 week scan, routine mid-trimester scan, and third-trimester scan. Specific regulatory parameters …
Read →The revised MUSA consensus (Harmsen et al., 2022) categorizes ultrasound signs of adenomyosis into direct (myometrial cysts, hyperechoic islands, echogenic subendometrial lines and 'buds') and indirect …
Read →IOTA recommends characterizing adnexal masses using benign descriptors, the ADNEX model, and a two-step strategy, which allows assigning an O-RADS category according to the ACR classification …
Read →Routine anatomical screening of the second trimester is performed according to a standardized protocol with a systematic review of fetal anatomy, biometry, assessment of the placenta, …
Read →According to ISUOG, fetal heart screening begins with the assessment of situs, cardiac axis, and rhythm. The structural review in routine screening should include the 4-chamber …
Read →Transvaginal cervicometry is the standard for measuring cervical length when assessing the risk of preterm birth. According to ISUOG, the method is highly operator-dependent, thus a …
Read →Fetal Growth Restriction (FGR) is diagnosed based on consensus Delphi criteria (Gordijn et al., 2016), which combine EFW, longitudinal growth assessment, and Doppler parameters (uterine arteries, …
Read →Dopplerometry in obstetrics includes the assessment of the PI of uterine arteries (UtA-PI), umbilical artery (UA-PI), and middle cerebral artery (MCA-PI), as well as the calculation …
Read →Ultrasound screening at 11–14 weeks combines maternal age, nuchal translucency thickness, and assessment of the ductus venosus/tricuspid regurgitation to detect trisomies 21, 18, and 13. Evaluation …
Read →Fetal biometry includes the measurement of biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL), followed by evaluation against percentile norms by …
Read →First trimester screening according to the updated ISUOG practice guidelines (performance of 11–14-week ultrasound scan, Ultrasound Obstet Gynecol 2023;61:127–143) is performed in the window of 11 …
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