Entrapment neuropathy of the ulnar nerve at the elbow, the so-called cubital tunnel syndrome, is the second most frequent focal mononeuropathy after carpal tunnel syndrome in adults. Currently, there is a pressing need to identify cost-effective biomarkers and procedures capable of accurately detecting alterations in ulnar nerve structural and functional integrity. Established electrophysiological techniques, such as motor and sensory nerve conduction studies, along with needle electromyography of specific muscles, represent the gold standard for ulnar nerve electrodiagnosis. Concurrently, the introduction of neuromuscular ultrasound and its integration into electromyographic laboratories has significantly impacted structural diagnosis and the precise localization of ulnar nerve pathology over the past two decades. In this review, our objective is to summarize the current knowledge on both classical and advanced diagnostic methods utilized in clinical neurophysiology laboratories. We aim to provide a synthesis of modern electrodiagnostic and neurosonographic techniques, with a particular emphasis on easily attainable, clinically relevant parameters.

The aim of this systematic review is to report the normal cortical development of different fetal cerebral fissures on ultrasound, describe associated anomalies in fetuses with cortical malformations, and evaluate the quality of published charts of cortical fissures. The inclusion criteria were studies reporting development, anomalies, and reference charts of fetal cortical structures on ultrasound. The outcomes observed were the timing of the appearance of different cortical fissures according to different gestational age windows, associated central nervous system (CNS) and extra-CNS anomalies detected at ultrasound in fetuses with cortical malformation, and rate of fetuses with isolated anomaly. Furthermore, we performed a critical evaluation of the published reference charts for cortical development on ultrasound. Random-effect meta-analyses of proportions were used to combine the data. Twenty-seven studies (6875 fetuses) were included. Sylvian fissure was visualized on ultrasound in 97.69% (95% CI 92.0-100) of cases at 18-19, 98.17% (95% CI 94.8-99.8) at 20-21, 98.94% (95% CI 97.0-99.9) at 22-23, and in all cases from 24 weeks of gestation. Parieto-occipital fissure was visualized in 81.56% (95% CI 48.4-99.3) of cases at 18-19, 96.59% (95% CI 83.2-99.8) at 20-21, 96.85% (95% CI 88.8-100) at 22-23, and in all cases from 24 weeks of gestation, while the corresponding figures for calcarine fissure were 37.27% (95% CI 0.5-89.6), 80.42% (95% CI 50.2-98.2), 89.18% (95% CI 74.0-98.2), and 96.02% (95% CI 96.9-100). Malformations of cortical development were diagnosed as an isolated finding at ultrasound in 6.21% (95% CI 2.9-10.9) of cases, while they were associated with additional CNS anomalies in 93.79% (95% CI 89.1-97.2) of cases. These findings highlight the need for large studies specifically looking at the timing of the appearance of the different brain sulci. Standardized algorithms for prenatal assessment of fetuses at high risk of malformations of cortical development are also warranted.

This review aims to explore the current application of Cranial Ultrasound Screening (CUS) in the diagnosis and treatment of brain diseases in extremely preterm infants. It also discusses the potential role of emerging ultrasound-derived technologies such as Super Microvascular Structure Imaging (SMI), Shear Wave Elastography (SWE), Ultrafast Doppler Ultrasound (UfD), and 3D ventricular volume assessment and automated segmentation techniques in clinical practice. A systematic search of medical databases was conducted using the keywords \"(preterm OR extremely preterm OR extremely low birth weight) AND (ultrasound OR ultrasound imaging) AND (neurodevelopment OR brain development OR brain diseases OR brain injury OR neuro*)\" to identify relevant literature. The titles, abstracts, and full texts of the identified articles were carefully reviewed to determine their relevance to the research topic. CUS offers unique advantages in early screening and monitoring of brain diseases in extremely preterm infants, as it can be performed at the bedside without the need for anesthesia or special monitoring. This technique facilitates early detection and intervention of conditions such as intraventricular hemorrhage, white matter injury, hydrocephalus, and hypoxic-ischemic injury in critically ill preterm infants. Continuous refinement of the screening and follow-up processes provides reliable clinical decision-making support for healthcare professionals and parents. Emerging ultrasound technologies, such as SWE, SMI, and UfD, are being explored to provide more accurate and in-depth understanding of brain diseases in extremely preterm infants. SWE has demonstrated its effectiveness in assessing the elasticity of neonatal brain tissue, aiding in the localization and quantification of potential brain injuries. SMI can successfully identify microvascular structures in the brain, offering a new perspective on neurologic diseases. UfD provides a high-sensitivity and quantitative imaging method for the prevention and treatment of neonatal brain diseases by detecting subtle changes in red blood cell movement and accurately assessing the status and progression of brain diseases. CUS and its emerging technologies have significant applications in the diagnosis and treatment of brain diseases in extremely preterm infants. Future research aims to address current technical challenges, optimize and enhance the clinical decision-making capabilities related to brain development, and improve the prevention and treatment outcomes of brain diseases in extremely preterm infants.

OBJECTIVE: to describe the normal features of the caudo-thalamic groove at antenatal brain ultrasound in a group of structurally normal fetuses at third trimester and to report a small series of cases with abnormal appearance of the caudothalamic groove at antenatal brain ultrasound.
METHODS: This was an observational study conducted at two referral Fetal Medicine units. A non-consecutive cohort of pregnant women with a singleton non anomalous pregnancy were prospectively recruited and underwent 3D ultrasound of the fetal brain at 28-32 weeks. At offline analysis the ultrasound volumes were adjusted in the multiplanar mode according to a standardized methodology, until the caudothalamic groove was visible on the parasagittal plane. To evaluate the inter-observer agreement, two operators were independently asked to indicate if the caudothalamic groove was visible unilaterally or bilaterally on each volume. The digital archives of the two Centres were also retrospectively searched to retrieve cases with abnormal findings at the level of the caudothalamic groove at antenatal brain ultrasound which were postnatally confirmed.
RESULTS: 180 non-consecutive cases fulfilling the inclusion criteria were prospectively included. At offline analysis of the 3D US volumes the caudo-thalamic groove was identified on the parasagittal plane by both operators at least unilaterally in 176 cases (97.8%) and bilaterally in 174 cases (96.6%). The K-coefficient for the agreement between the two independent operators in recognizing the caudo-thalamic groove was 0.89 and 0.83 on one and both hemispheres respectively. At the retrospective search of our archives 5 cases with abnormal appearance of the groove at antenatal brain ultrasound (2 haemorrhage and 3 cyst) were found.
CONCLUSIONS: Our study has demonstrated that the caudo-thalamic groove is consistently seen among normal fetuses at third trimester submitted to multiplanar neurosonography and that abnormal findings at this level may be antenatally detected. This article is protected by copyright. All rights reserved.

Brain injury and poor neurodevelopment have been consistently reported in infants and adults born before term. These changes occur, at least in part, prenatally and are associated with intra-amniotic inflammation. The pattern of brain changes has been partially documented by magnetic resonance imaging but not by neurosonography along with amniotic fluid brain injury biomarkers.
This study aimed to evaluate the prenatal features of brain remodeling and injury in fetuses from patients with preterm labor with intact membranes or preterm premature rupture of membranes and to investigate the potential influence of intra-amniotic inflammation as a risk mediator.
In this prospective cohort study, fetal brain remodeling and injury were evaluated using neurosonography and amniocentesis in singleton pregnant patients with preterm labor with intact membranes or preterm premature rupture of membranes between 24.0 and 34.0 weeks of gestation, with (n=41) and without (n=54) intra-amniotic inflammation. The controls for neurosonography were outpatient pregnant patients without preterm labor or preterm premature rupture of membranes matched 2:1 by gestational age at ultrasound. Amniotic fluid controls were patients with an amniocentesis performed for indications other than preterm labor or preterm premature rupture of membranes without brain or genetic defects whose amniotic fluid was collected in our biobank for research purposes matched by gestational age at amniocentesis. The group with intra-amniotic inflammation included those with intra-amniotic infection (microbial invasion of the amniotic cavity and intra-amniotic inflammation) and those with sterile inflammation. Microbial invasion of the amniotic cavity was defined as a positive amniotic fluid culture and/or positive 16S ribosomal RNA gene. Inflammation was defined by amniotic fluid interleukin 6 concentrations of >13.4 ng/mL in preterm labor and >1.43 ng/mL in preterm premature rupture of membranes. Neurosonography included the evaluation of brain structure biometric parameters and cortical development. Neuron-specific enolase, protein S100B, and glial fibrillary acidic protein were selected as amniotic fluid brain injury biomarkers. Data were adjusted for cephalic biometrics, fetal growth percentile, fetal sex, noncephalic presentation, and preterm premature rupture of membranes at admission.
Fetuses from mothers with preterm labor with intact membranes or preterm premature rupture of membranes showed signs of brain remodeling and injury. First, they had a smaller cerebellum. Thus, in the intra-amniotic inflammation, non-intra-amniotic inflammation, and control groups, the transcerebellar diameter measurements were 32.7 mm (interquartile range, 29.8-37.6), 35.3 mm (interquartile range, 31.2-39.6), and 35.0 mm (interquartile range, 31.3-38.3), respectively (P=.019), and the vermian height measurements were 16.9 mm (interquartile range, 15.5-19.6), 17.2 mm (interquartile range, 16.0-18.9), and 17.1 mm (interquartile range, 15.7-19.0), respectively (P=.041). Second, they presented a lower corpus callosum area (0.72 mm2 [interquartile range, 0.59-0.81], 0.71 mm2 [interquartile range, 0.63-0.82], and 0.78 mm2 [interquartile range, 0.71-0.91], respectively; P=.006). Third, they showed delayed cortical maturation (the Sylvian fissure depth-to-biparietal diameter ratios were 0.14 [interquartile range, 0.12-0.16], 0.14 [interquartile range, 0.13-0.16], and 0.16 [interquartile range, 0.15-0.17], respectively [P<.001], and the right parieto-occipital sulci depth ratios were 0.09 [interquartile range, 0.07-0.12], 0.11 [interquartile range, 0.09-0.14], and 0.11 [interquartile range, 0.09-0.14], respectively [P=.012]). Finally, regarding amniotic fluid brain injury biomarkers, fetuses from mothers with preterm labor with intact membranes or preterm premature rupture of membranes had higher concentrations of neuron-specific enolase (11,804.6 pg/mL [interquartile range, 6213.4-21,098.8], 8397.7 pg/mL [interquartile range, 3682.1-17,398.3], and 2393.7 pg/mL [interquartile range, 1717.1-3209.3], respectively; P<.001), protein S100B (2030.6 pg/mL [interquartile range, 993.0-4883.5], 1070.3 pg/mL [interquartile range, 365.1-1463.2], and 74.8 pg/mL [interquartile range, 44.7-93.7], respectively; P<.001), and glial fibrillary acidic protein (1.01 ng/mL [interquartile range, 0.54-3.88], 0.965 ng/mL [interquartile range, 0.59-2.07], and 0.24 mg/mL [interquartile range, 0.20-0.28], respectively; P=.002).
Fetuses with preterm labor with intact membranes or preterm premature rupture of membranes had prenatal signs of brain remodeling and injury at the time of clinical presentation. These changes were more pronounced in fetuses with intra-amniotic inflammation.

OBJECTIVE: To evaluate corpus callosum (CC) size in fetuses with malformations of cortical development (MCD) and to explore the diagnostic value of three CC length (CCL) ratios in identifying cortical abnormalities.
METHODS: This is a single-center retrospective study in singleton fetuses at 20-37 weeks of gestation between April 2017 and August 2022. The midsagittal plane of the fetal brain was obtained and evaluated for the following variables: length, height, area of the corpus callosum, and relevant markers, including the ratios of corpus callosum length to internal cranial occipitofrontal dimension (CCL/ICOFD), corpus callosum length to femur length (CCL/FL), and corpus callosum length to cerebellar vermian diameter (CCL/VD). Intra-class correlation coefficient (ICC) was used to evaluate measurement consistency. The accuracy of biometric measurements in prediction of MCD was assessed using the area under the receiver-operating-characteristics curves (AUC).
RESULTS: Fetuses with MCD had a significantly decreased CCL, height (genu and splenium), and area as compared with those of normal fetuses (P < .05), but there was no significant difference in body height (P = .326). The CCL/ICOFD, CCL/FL, and CCL/VD ratios were significantly decreased in fetuses with MCD when compared with controls (P < .05). The CCL/ICOFD ratio offered the highest predictive accuracy for MCD, yielding an AUC of 0.856 (95% CI: 0.774-0.938, P < .001), followed by CCL/FL ratio (AUC, 0.780 (95% CI: 0.657-0.904), P < .001), CCL/VD ratio (AUC, 0.677 (95% CI: 0.559-0.795), P < .01).
CONCLUSIONS: The corpus callosum biometric parameters in fetuses with MCD are reduced. The CCL/ICOFD ratio derived from sonographic measurements is considered a promising tool for the prenatal detection of cortical malformations. External validation of these findings and prospective studies are warranted.

BACKGROUND: Growth-restricted fetuses may have changes in their neuroanatomical structures that can be detected in prenatal imaging. We aim to compare corpus callosal length (CCL) and cerebellar vermian height (CVH) measurements between fetal growth restriction (FGR) and control fetuses and to correlate them with cerebral Doppler velocimetry in growth-restricted fetuses.
METHODS: This was a prospective cohort of FGR after 20 weeks of gestation with ultrasound measurements of CCL and CVH. Control cohort was assembled from fetuses without FGR who had growth ultrasound after 20 weeks of gestation. We compared differences of CCL or CVH between FGR and controls. We also tested for the correlations of CCL and CVH with middle cerebral artery (MCA) pulsatility index (PI) and vertebral artery (VA) PI in the FGR group. CCL and CVH measurements were adjusted by head circumference (HC).
RESULTS: CCL and CVH were obtained in 68 and 55 fetuses, respectively. CCL/HC was smaller in FGR fetuses when compared to control fetuses (difference = 0.03, 95% CI: [0.02, 0.04], p < 0.001). CVH/HC was larger in FGR fetuses compared to NG fetuses (difference = 0.1, 95% CI: [-0.01, 0.02], p = < 0.001). VA PI multiples of the median were inversely correlated with CVH/HC (rho = -0.53, p = 0.007), while CCL/HC was not correlated with VA PI. Neither CCL/HC nor CVH/HC was correlated with MCA PI.
CONCLUSIONS: CCL/HC and CVH/HC measurements show differences in growth-restricted fetuses compared to a control cohort. We also found an inverse relationship between VA PI and CVH/HC. The potential use of neurosonography assessment in FGR assessment requires continued explorations.

UNASSIGNED: Ultrasonographic examination is the first-tier test to detect abnormal development of central nervous system (CNS). In optimal conditions, neurosonography can detect all important hallmarks of CNS development. It is, however, not known how the performance of this modality is in a routine setting. We aimed to evaluate the feasibility of neurosonography in a time-limited routine setting.
UNASSIGNED: We have performed a prospective study in which we have included a group of pregnant women carrying a fetus with an isolated congenital heart defect (CHD), and a control group of fetuses without structural anomalies. We have performed basic neurosonography examination according to the guideline \'how to perform a basic screening examination of the CNS\', published by the international society of ultrasound in obstetrics and gynecology in both groups. In all these examinations, 9 brain structures were scored in 3 different planes, by researchers that were blinded for group allocation. A sufficient neurosonogram was performed when 7 or more out of 9 CNS structures were clearly visible during the off-line scoring of the examination.
UNASSIGNED: A total of 574 neurosonographic examinations were performed in 151 fetuses, 90 in the CHD-group and 61 in the control group. A sufficient neurosonogram could be performed in 79% (234/294) of cases in a clinical setting (CHD cases) and in 90% (253/280) of control pregnancies. Higher maternal BMI (>30), maternal age, fetal cephalic position, fetal gender and placental position did not significantly influence neurosonography scores.
UNASSIGNED: In clinical setting, basic fetal neurosonography can be sufficiently performed in the majority of cases. This was not significantly influenced by maternal or fetal factors. The optimal gestational age for neurosonography is between 22 and 34 weeks.

UNASSIGNED: To investigate midbrain growth, including corpus callusum (CC), cerebellar vermis (CV) and cortical development in late fetal growth restriction (FGR) depending on uterine artery (UtA) Pulsatility Index (PI) values.
UNASSIGNED: This was a prospective study including singleton fetuses with late FGR characterized by abnormal cerebral placental ratio (CPR). According to UtA PI values, the FGR fetuses were subdivided into normal ≤95th centile) and abnormal (>95th centile). Neurosonography was performed at 33-44 weeks of gestations to assess CC and CV lengths and the depth of Sylvian fissure (SF), parieto-occipital (POF) and calcarine fissures (CF). Neurosonographic variables were normalized for fetal head circumference size.
UNASSIGNED: The study cohort included 60 fetuses with late FGR, 39 with normal UtA PI and 21 with abnormal PI values. The latter group showed significant differences in CC (median (interquartile range) normal 35.9 (28.49-45.53) vs abnormal UtA PI 25.31(19.76-35.13) mm; p < 0.0022), CV (normal 25.78 (18.19-29.35) abnormal UtA PI 17.03 (14.07-24.16)mm; p = 0.0067); SF (normal 10.58 (8.99-11.97)vs abnormal UtA PI 7.44 (6.23-8.46) mm; p < 0.0001), POF (normal 6.85 (6.35-8.14) vs abnormal UtA PI 4.82 (3.46-7.75) mm; p < = 0.0184) and CF (normal 04.157 (2.85-5.41) vs abnormal UtA PI 2.33 (2.49-4.01)); p < 0.0382).
UNASSIGNED: Late onset FGR fetuses with abnormal UtA PI showed shorter CC and CV length and delayed cortical development compared to those with normal uterine PI. These findings support the existence of a link between abnormal brain development and changes in utero placental circulation.

OBJECTIVE: To investigate midbrain growth, including corpus callusum (CC) and cerebellar vermis (CV) and cortical development in late fetal growth restricted (FGR) subclassified according to the umbilical vein blood flow (UVBF) values.
METHODS: This was a prospective study on singleton fetuses late FGR with abnormal placental cerebral ratio (PCR). FGR fetuses were further subdivided into normal (≥fifth centile) and abnormal (neurosonography was performed at 33-34 weeks of gestation to assess CC and CV lengths and the depth of Sylvian fissure (SF), parieto-occipital (POF) and calcarine fissures (CF). Neurosonographic variables were normalized for fetal head circumference size.
RESULTS: The study cohort included 60 late FGR, 31 with normal UVBF/AC and 29 with abnormal UVBF/AC values. The latter group showed significant differences in CC (median (interquartile range (IQR) normal 0.96 (0.73-1.16) vs. abnormal UVBF/AC 0.60 (0.47-0.87); p<0.0001)), CV (normal 1.04 (0.75-1.26) vs. abnormal UVBF (AC 0.76 (0.62-1.18)); p=0.0319), SF (normal 0.83 (0.74-0.93) vs. abnormal UVBF/AC 0.56 (0.46-0.68); p<0.0001), POF (normal 0.80 (0.71-0.90) vs. abnormal UVBF/AC l 0.49 (0.39-0.90); p≤0.0072) and CF (normal 0.83 (0.56-1.01) vs. abnormal UVBF/AC 0.72 (0.53-0.80); p<0.029).
CONCLUSIONS: Late onset FGR fetuses with of reduced umbilical vein flow showed shorter CC and CV length and a delayed cortical development when compared to those with normal umbilical vein hemodynamics. These findings support the existence of a link between abnormal brain development and changes in umbilical vein circulation.