[Abdominal and cranial ultrasound screenings in our Neonatal Intensive Care Unit]. / Hasi és agyi ultrahang-szurovizsgálatok Neonatális Intenzív Centrumunkban.

INTRODUCTION: Previously, all admitted neonates to our tertiary Neonatal Unit, University of Szeged, had a cranial and abdominal ultrasound performed as part of their care. OBJECTIVE: To analyze the findings and to evaluate the effectiveness of the universal ultrasound screening. METHOD: Results of cranial and abdominal ultrasound imaging performed in our Unit between 1st January 2014 and 31st December 2015 were analyzed retrospectively. Abnormalities found during the screening scans were studied further and assessed until discharge and during the first 2 years. All imagings were performed by a radiologist. RESULTS: During the examined 2 years, 579 neonates were admitted (gestational age mean 34.2 weeks [23-41, SD ± 4.04]), abdominal ultrasound was performed in 562 (97%) and cranial ultrasound in 560 (97%) babies, on the 3.6th day of life at an average (0-18, SD ± 2.24). Of all abdominal ultrasound scans, 87% (n = 488) was carried out as screening, and the found abnormalities in 140 (29%) of the cases: renal pelvic dilatation (n = 67 [47.9%]), free abdominal fluid (n = 17 [12.1%]), echogenic kidneys (n = 13 [9.3%]), congenital abnormalities of the kidney and urinary tract (n = 9 [6.4%]), abnormalities of the liver, bile system, adrenal gland [n = 14 [10%]). The screening identified 4 (0.8%) neonates with renal abnormilaties requiring surgical correction. In regards of renal abnormalities, we observed male (p = 0.18) and left sided (p = 0.54) predominance. Screening cranial ultrasound was performed in 65% (n = 362) of all neonates, discovering 51 (14%) anomalies: plexus chorioideus cyst (n = 21 [41%]), plexus chorioideus hemorrhage (n = 9 [17.6%]), mild ventricular asymmetry (n = 8 [15.7%]), subependymal hemorrhage (n = 5 [9.8%]), abnormalities of the periventricular area (n = 4 [7.8%]), colpocephaly, hydrocephalus externus, echogenic meninx and thalamic nodule [n = 1-1 (1.9-1.9%)]. CONCLUSION: Abdominal ultrasound screening discovered renal abnormalities and umbilical line complications as clinically relevant findings. However, a small number of renal abnormalities identified by screening required surgical intervention. Further studies are needed to identify possible risk groups to develop more efficient screening strategy to decrease the number of screened babies for 1 relevant finding (number to screen). Cranial ultrasound screening did not identify any abnormalities that needed intervention. We can not recommend universal cranial ultrasound screening based on our results. Orv Hetil. 2023; 164(31): 1222-1230.

Ultrasound Technologies for Imaging and Modulating Neural Activity.

Visualizing and perturbing neural activity on a brain-wide scale in model animals and humans is a major goal of neuroscience technology development. Established electrical and optical techniques typically break down at this scale due to inherent physical limitations. In contrast, ultrasound readily permeates the brain, and in some cases the skull, and interacts with tissue with a fundamental resolution on the order of 100 µm and 1 ms. This basic ability has motivated major efforts to harness ultrasound as a modality for large-scale brain imaging and modulation. These efforts have resulted in already-useful neuroscience tools, including high-resolution hemodynamic functional imaging, focused ultrasound neuromodulation, and local drug delivery. Furthermore, recent breakthroughs promise to connect ultrasound to neurons at the genetic level for biomolecular imaging and sonogenetic control. In this article, we review the state of the art and ongoing developments in ultrasonic neurotechnology, building from fundamental principles to current utility, open questions, and future potential.

Preterm white matter injury: ultrasound diagnosis and classification.

White matter injury (WMI) is the most frequent form of preterm brain injury. Cranial ultrasound (CUS) remains the preferred modality for initial and sequential neuroimaging in preterm infants, and is reliable for the diagnosis of cystic periventricular leukomalacia. Although magnetic resonance imaging is superior to CUS in detecting the diffuse and more subtle forms of WMI that prevail in very premature infants surviving nowadays, recent improvement in the quality of neonatal CUS imaging has broadened the spectrum of preterm white matter abnormalities that can be detected with this technique. We propose a structured CUS assessment of WMI of prematurity that seeks to account for both cystic and non-cystic changes, as well as signs of white matter loss and impaired brain growth and maturation, at or near term equivalent age. This novel assessment system aims to improve disease description in both routine clinical practice and clinical research. Whether this systematic assessment will improve prediction of outcome in preterm infants with WMI still needs to be evaluated in prospective studies.

State-of-the-art neonatal cerebral ultrasound: technique and reporting.

In the past three decades, cerebral ultrasound (CUS) has become a trusted technique to study the neonatal brain. It is a relatively cheap, non-invasive, bedside neuroimaging method available in nearly every hospital. Traditionally, CUS was used to detect major abnormalities, such as intraventricular hemorrhage (IVH), periventricular hemorrhagic infarction, post-hemorrhagic ventricular dilatation, and (cystic) periventricular leukomalacia (cPVL). The use of different acoustic windows, such as the mastoid and posterior fontanel, and ongoing technological developments, allows for recognizing other lesion patterns (e.g., cerebellar hemorrhage, perforator stroke, developmental venous anomaly). The CUS technique is still being improved with the use of higher transducer frequencies (7.5-18 MHz), 3D applications, advances in vascular imaging (e.g. ultrafast plane wave imaging), and improved B-mode image processing. Nevertheless, the helpfulness of CUS still highly depends on observer skills, knowledge, and experience. In this special article, we discuss how to perform a dedicated state-of-the-art neonatal CUS, and we provide suggestions for structured reporting and quality assessment.

Pediatric encephalic ultrasonography: the essentials.

Nowadays, cranial ultrasonography (US) of the newborn represents the first imaging method in brain damage study and its possible outcomes. This exam is performed using the natural fontanelles, especially the anterior one. It is fast, non-invasive and does not produce any side effect. Ultrasonographic examination is usually performed in cases of prematurity, especially in children with birth weight less than 1500 g, because important informations about the possible presence of pathologies such as cerebral hemorrhage and hypoxic-ischemic encephalopathy are given. This approach can be useful also in the study of pre- and post-natal infections, for example, type II Herpes Simplex virus or Cytomegalovirus infections, or pointing out vascular malformations such as vein of Galen aneurysm. Although less important than methods such as computed tomography (CT) and magnetic resonance imaging (MRI) in the evaluation of trauma and tumors, ultrasound can provide useful informations or be used in first instance in the suspicion of a brain mass.

The most useful cranial ultrasound predictor of neurodevelopmental outcome at 2 years for preterm infants.

AIM: To determine the most important cranial ultrasound predictors of abnormality associated with neurodevelopmental outcome at 2 years of age in preterm infants. MATERIALS AND METHODS: A total of 343 preterm infants born between 2005 and 2010 and cared for in KK Women's and Children's Hospital, a tertiary paediatric hospital, with birth weight ≤1,250 g were assessed in this retrospective study. Serial cranial ultrasound examinations were examined for intraventricular haemorrhage and cystic periventricular leukomalacia. Ventricular-brain ratio on term equivalent cranial ultrasound was measured. Neurodevelopmental outcome was assessed by the performance on Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III) at 2 years corrected age. Mental delay was defined as having a combined Bayley-III score (the average of cognitive and language scores) <80. RESULTS: The mean cognitive, language, and motor scores on Bayley-III in this cohort were 93±15, 83±18, and 92±15, respectively. Twenty-six percent of the preterm infants had mental delay and 4% had cerebral palsy. Ventricular-brain ratio >0.35 was the most significant factor associated with mental delay (odds ratio 5.28, 95% CI: 1.49-18.71, p=0.01). Other significant risk factors for mental delay were male gender, postnatal steroids, and necrotising enterocolitis, whereas maternal tertiary education was a protective factor against adverse outcome. CONCLUSION: Ventricular-brain ratio >0.35 on term-equivalent cranial ultrasound in preterm infants is the strongest predictor for mental delay on Bayley score at 2 years of age.

Early Prediction of Periventricular Leukomalacia Using Quantitative Texture Analysis of Serial Cranial Ultrasound Scans in Very Preterm Infants.

We compared texture parameters of serial cranial ultrasound (cUS) images of periventricular leukomalacia (PVL) and normal periventricular echogenicity (PVE) in very preterm infants and evaluated the early predictive values of texture analysis (TA) for PVL. Ten individuals with PVL and 10 control individuals with PVE assessed with an initial cUS within 1 wk of birth and follow-up cUS at 2-3 and 4-6 wk of life were included. TA was performed on the region of interest of PVE at the parieto-occipital area on serial cUS. Opposite changes in variance were obtained between the first two cUS sessions in both groups (p = 0.017 in PVL and p = 0.005 in PVE). The variance-to-mean ratio (VMR) between the second and first cUS sessions differed (p = 0.016) and reliably stratified the groups (area under the receiver operating characteristic curve: 0.820, 95% confidence interval: 0.587-1.000, sensitivity: 100%, specificity: 60%). TA of serial cUS helps to predict PVL within 3 wk of life.

Brain Volumes of very Low Birth Weight Infants Measured by Two-dimensional Cranial Ultrasonography: A Prospective Cohort Study.

BACKGROUND: Cranial ultrasonography is the main neuroimaging technique for very low birth weight infants. Low brain volume is associated with poor neurologic outcome. This study aimed to calculate brain volumes of preterm infants with two-dimensional measurements of cranial ultrasonography. METHODS: Intracranial height, anteroposterior diameter, bi-parietal diamater, ventricular height, thalamo-occipital distance and ventricular index were measured with routine cranial ultrasonographic scanning. Brain considered a spheric, ellipsoid model and estimated brain volume (EBV) was calculated by subtracting two lateral ventricular volumes from the total brain volume. RESULTS: One hundred and twenty-one preterm infants under a birth weight of 1500 g and 32 weeks of gestational age were included in this study. The mean gestational age of study population was 27.7 weeks, and mean birthweight was 1057 grams. Twenty-two of 121 infants had dilated ventricle, in this group, EBV was lower than normal group (202 ± 58 cm3 vs 250 ± 53 cm3, respectively, p<0.01). Advanced resuscitation, bronchopulmonary dysplasia and late-onset sepsis were found to be independent risk factors for low brain volume in our data. CONCLUSION: Estimated brain volume can be calculated by two-dimensional measurements with cranial ultrasonography.

Neurosonography: Assessing the Premature Infant.

Neurosonography has proven to be helpful in neonatal brain diagnosis. Premature infants are at great risk for intraventricular hemorrhage and periventricular leukomalacia, key abnormalities affecting developmental outcome. Here we discuss technique, anatomy, variants and key points for diagnosis.

Ultrasonography During Surgery to Approach Cerebral Metastases: Effect on Karnofsky Index Scores and Tumor Volume.

BACKGROUND: The goals of treating a cerebral metastasis (CM) are to achieve local control of the disease and to improve patient quality of life. The aim of this study was to analyze the effect of conventional surgery supported by intraoperative ultrasound (IOUS) to approach a CM. To perform this analysis, we determined the postoperative Karnofsky Performance Status Scale (KPS) scores and tumor resection grades. METHODS: Patients with a CM diagnosis were included in this study. Surgical treatment was either supported or not by IOUS. Pre- and postoperative KPS scores were determined by the oncology team, and cerebral tumor volume was estimated through pre- and postoperative magnetic resonance imaging. The surgical team determined whether it was possible to perform a total CM resection. RESULTS: There were 78 patients treated using surgical management (35 with and 43 without IOUS). In the IOUS group, the postoperative KPS scores were higher (80 vs. 70, respectively; P = 0.045) and the KPS evolution was superior (P = 0.036), especially in the following subgroups: difficulty of tumor resection ranking score <4 (P = 0.037), tumor in an eloquent area (P = 0.043), tumor not associated with vessels or nerves (P = 0.007), and solitary lesions (P = 0.038). The residual tumor volume was lower in the IOUS group (9.5% and 1.6 mm3 vs. 30.8% and 9 mm3, respectively; P = 0.05). In patients with a KPS score ≥70, 62% of them had <10% residual tumors (76% in the IOUS group and 45% in the non-IOUS group; P = 0.032; odds ratio, 3.8). CONCLUSIONS: IOUS may improve postoperative KPS scores and decrease residual tumor volumes in CM surgeries. These findings should be confirmed in future studies.

Risk factors for periventricular echodensities and outcomes in preterm infants.

OBJECTIVES: To determine the incidence, risk factors and outcomes associated with transient and/or persistent periventricular echodensities (PVED) among preterm infants. METHODS: Medical records of preterm infants born at ≤ 32 weeks gestational age (GA) with PVED and no other brain pathology were reviewed and compared to matched control infants in a case-controlled retrospective study. Neurodevelopmental outcomes at 8-24 months corrected age were documented. RESULTS: A 17.8% incidence of PVED was recorded, with the highest incidence of 30-40% recorded at 29-31 weeks GA. Study and control groups were similar for all maternal parameters and neonatal morbidities, except for a higher incidence of respiratory distress syndrome among the study group. PVED at one month of age was predicted by 5 min Apgar score < 7 [OR = 33.78 (CI 2.94-388.06, p = 0.005)]. PVED was not associated with long-term neurodevelopmental disability. CONCLUSIONS: No risk factors or specific associated morbidities were identified among preterm infants with transient PVED. PVED at one month of age was predicted by low 5 min Apgar scores, possibly suggesting different pathogenesis or timing between the groups. Long-term outcome studies are needed to determine PVED impact.

Structural Ultrasound of the Medial Temporal Lobe in Alzheimer's Disease.

Purpose One of the anatomical hallmarks of Alzheimer's disease (AD) is the atrophy of the medial temporal lobe (MTL), yet cost-effective and broadly available methodological alternatives to the current imaging tools for screening of this brain area are not currently available. Materials and Methods Using structural transcranial ultrasound (TCS), we attempted to visualize and measure the MTL, and compared the results of 32 AD patients and 84 healthy controls (HC). The MTL and the surrounding space were defined in the coronal plane on TCS. A ratio of the height of the MTL/height of the choroidal fissure (M/F) was calculated in order to obtain a regional proportion. Results An insufficient temporal bone window was identified in 22 % of the AD patients and 12 % of the HCs. The results showed that the ratio of M/F was significantly smaller in the AD group on both sides (p = 0.004 right, p = 0.007 left side). Furthermore, the M/F ratio made it possible to discriminate AD patients from HCs with a sensitivity of 83 % (right)/73 % (left) and a specificity of 76 % (right)/72 % (left) which is basically comparable to results published for magnetic resonance imaging. The measurements showed substantial intra/interrater reliability (ICC:0.79/0.69). Conclusion These results suggest that utilization of structural TCS may possibly constitute a cheap and easy-to-use supplement to other techniques for the diagnosis of AD. It may be especially useful as a screening tool in the large population of individuals with cognitive decline. Further studies are needed to validate this novel method.

Imaging of Neurologic Conditions in Pregnant Patients.

A number of physiologic, hormonal, immunologic, and hemodynamic changes take place in the maternal body during pregnancy. The majority of these changes are essential for maintaining the normal course of pregnancy. However, these changes may also cause acute or chronic conditions that affect various biologic systems in the mother. In addition, conditions of the central and peripheral nervous systems can cause a variety of neurologic symptoms and complications. Neurologic signs and symptoms in pregnant and postpartum women may be due to the exacerbation of a preexisting medical condition, the initial manifestation of a primary central nervous system-related problem, or a neurologic problem unique to pregnancy and the postpartum period. Because the symptoms of these conditions are either nonspecific or overlapping, it can be challenging to pinpoint the diagnosis clinically. These conditions can be classified into more commonly seen conditions such as headache, venous thrombosis, preeclampsia, subarachnoid hemorrhage, posterior reversible encephalopathy syndrome, and certain pituitary disorders; and less commonly seen entities such as aneurysm, arteriovenous malformation, primary or secondary neoplasm, Sheehan syndrome, and Wernicke encephalopathy. Imaging has an important role in the differentiation and exclusion of various neurologic conditions, and most of the time, imaging findings can point the clinician to a specific diagnosis. The imaging appearances of common and uncommon neurologic conditions that can occur during pregnancy and the early postpartum period are highlighted in this article. ©RSNA, 2016.

Intraoperative Ultrasound Technology in Neuro-Oncology Practice-Current Role and Future Applications.

BACKGROUND: Surgery for cranial and spinal tumors has evolved tremendously over the years. Not only have neuro-oncologists been able to better understand tumor biology and thereby improve multimodality therapy, but advances in surgical techniques have also directly equipped neurosurgeons with the armamentarium necessary to achieve more radical resections safely. Intraoperative imaging tools are one such adjunct. Though intraoperative magnetic resonance (MR) has emerged as the "gold standard" among these, logistical challenges make it difficult to implement across all centers. On the other hand, the use of ultrasound (US) intraoperatively predates the use of MR. Over the past 4 decades, technologic improvements have refined and expanded the scope and application of intraoperative US technology. Strategies to maximize its efficacy and overcome the various limitations have evolved. A large volume of clinical experience has accumulated with respect to its role as an adjunct specifically in tumor surgery. METHODS: We performed a literature review to evaluate the role of IOUS in tumor surgery. This review traces the evolution of intraoperative US over the years and reviews the current scope and applications with respect to neuro-oncologic surgery, as well as potential future applications. RESULTS: IOUS has evolved over the years since its introduction. Advances in technology have provided real-time navigated and 3-D techniques, which overcome many of the limitations of older IOUS techniques. This has shown to be very useful in not only localization of lesions, but also in improving resection rates as well as survival. CONCLUSIONS: IOUS is a powerful and versatile multipurpose intraoperative adjunct in tumor surgery, especially for resection control. The learning curve is relatively easy to climb and future improvements in technology are likely to widen the scope of its use.

Diagnostic imaging of posterior fossa anomalies in the fetus.

Ultrasound and magnetic resonance imaging are the two imaging modalities used in the assessment of the fetus. Ultrasound is the primary imaging modality, whereas magnetic resonance is used in cases of diagnostic uncertainty. Both techniques have advantages and disadvantages and therefore they are complementary. Standard axial ultrasound views of the posterior fossa are used for routine scanning for fetal anomalies, with additional orthogonal views directly and indirectly obtainable using three-dimensional ultrasound techniques. Magnetic resonance imaging allows not only direct orthogonal imaging planes, but also tissue characterization, for example to search for blood breakdown products. We review the nomenclature of several posterior fossa anomalies using standardized criteria, and we review cerebellar abnormalities based on an etiologic classification.

Feasibility of the Combined Application of Navigated Probabilistic Fiber Tracking and Navigated Ultrasonography in Brain Tumor Surgery.

BACKGROUND: Surgical resection of intra-axial tumors is a challenging procedure because of indistinct tumor margins, infiltration, and displacement of white matter tracts surrounding the lesion. Hence, gross total tumor resection without causing new neurologic deficits is demanding, especially in tumor sites adjoining eloquent structures. Feasibility of the combination of navigated probabilistic fiber tracking to identify eloquent fiber pathways and navigated ultrasonography to control brain shift was tested. METHODS: Eleven patients with lesions adjacent to eloquent white matter structures (pyramidal tract, optic radiation and arcuate fascicle) were preoperatively subjected to magnetic resonance imaging including diffusion-weighted imaging on a 3-T magnetic resonance system (Trio [Siemens, Erlangen, Germany]). Probabilistic fiber tracking was performed using the tools of the FMRIB Software Library (FSL). Results of probabilistic fiber tracking and high-resolution anatomic images were integrated into the neuronavigation system Stealth Station (Medtronic, Minneapolis, Minnesota, USA) together with the navigated ultrasonography (SonoNav [Medtronic]). RESULTS: FSL-based probabilistic fiber tracking depicted the pyramidal tract, the optic radiation, and arcuate fascicle anatomically plausibly. Integration of the probabilistic fiber tracking into neuronavigation was technically feasible and allowed visualization of the reconstructed fiber pathways. Navigated ultrasonography controlled brain shift. CONCLUSIONS: Integration of probabilistic fiber tracking and navigated ultrasonography into intraoperative neuronavigation facilitated anatomic orientation during glioma resection. FSL-based probabilistic fiber tracking integrated sophisticated fiber tracking algorithms, including modeling of crossing fibers. Combination with navigated ultrasonography provided a three-dimensional estimation of intraoperative brain shift and, therefore, improved the reliability of neuronavigation.

Intraoperative 3D contrast-enhanced ultrasound (CEUS): a prospective study of 50 patients with brain tumours.

BACKGROUND: Reliable intraoperative resection control during surgery of malignant brain tumours is associated with the longer overall survival of patients. B-mode ultrasound (BUS) is a familiar intraoperative imaging application in neurosurgical procedures and supplies excellent image quality. However, due to resection-induced artefacts, its ability to distinguish between tumour borders, oedema, surrounding tissue and tumour remnants is sometimes limited. In experienced hands, this "bright rim effect" could be reduced. However, it should be determined, if contrast-enhanced ultrasound can improve this situation by providing high-quality imaging during the resection. The aim of this clinical study was to examine contrast-enhanced and three-dimensional reconstructed ultrasound (3D CEUS) in brain tumour surgery regarding the uptake of contrast agent pre- and post-tumour resection, imaging quality and in comparison with postoperative magnetic resonance imaging in different tumour entities. METHODS: Fifty patients, suffering from various brain tumours intra-axial and extra-axial, who had all undergone surgery with the support of neuronavigation in our neurosurgical department, were included in the study. Their median age was 56 years (range, 28-79). Ultrasound imaging was performed before the Dura was opened and for resection control at the end of tumour resection as defined by the neurosurgeon. A high-end ultrasound (US) device (Toshiba Aplio XG®) with linear and sector probes for B-mode and CEUS was used. Navigation and 3D reconstruction were performed with a LOCALITE SonoNavigator® and the images were transferred digitally (DVI) to the navigation system. The contrast agent consists of echoic micro-bubbles showing tumour vascularisation. The ultrasound images were compared with the corresponding postoperative MR data in order to determine the accuracy and imaging quality of the tumours and tumour remnants after resection. RESULTS: Different types of tumours were investigated. High, dynamic contrast agent uptake was observed in 19 of 21 patients (90 %) suffering from glioblastoma, while in 2 patients uptake was low and insufficient. In 52.4 % of glioblastoma and grade III astrocytoma patients CEUS led to an improved delineation in comparison to BUS and showed a high-resolution imaging quality of the tumour margins and tumour boarders. Grade II and grade III astrocytoma (n = 6) as well as metastasis (n = 18) also showed high contrast agent uptake, which led in 50 % to an improved imaging quality. In 5 of these 17 patients, intraoperative CEUS for resection control showed tumour remnants, leading to further tumour resection. Patients treated with CEUS showed no increased neurological deficits after tumour resection. No pharmacological side-effects occurred. CONCLUSIONS: Three-dimensional CEUS is a reliable intraoperative imaging modality and could improve imaging quality. Ninety percent of the high-grade gliomas (HGG, glioblastoma and astrocytoma grade III) showed high contrast uptake with an improved imaging quality in more than 50 %. Gross total resection and incomplete resection of glioblastoma were adequately highlighted by 3D CEUS intraoperatively. The application of US contrast agent could be a helpful imaging tool, especially for resection control in glioblastoma surgery.

Routine Screening Ultrasound in Children With Cleft Palate and/or Lip: A Single Center Experience.

The aim of this study is to evaluate the incidence of associated congenital anomalies that is picked up by screening ultrasound of the heart, urinary system, and central nervous system (CNS) of children with cleft palate and/or lip deformities in a single regional center. A total of 225 children with cleft deformities were recruited in the study in 2009 to 2013, 91% of them underwent screening echocardiogram and of these, 98% of them were normal findings that do not require further follow-up ultrasound or treatment. Total 85% of the children underwent screening ultrasound of the urinary system and CNS, and of these, 99% were reported to have normal findings. Medium term follow-up of these children did not reveal any significant structural anomalies in the heart, brain, and urinary system that might have missed in the initial ultrasound screening. The authors suggest that in resource-limited settings, routine ultrasound screening of the heart, the CNS, and the urinary system may not be required in asymptomatic and nonsyndromic infants with cleft deformities and in those with "lip-only" cleft deformity.

Do normal head ultrasounds need repeating in infants less than 30 weeks gestation?

OBJECTIVE: Current head ultrasound (HUS) screening recommendations in preterm infants often include a repeat HUS, regardless of initial findings. The objective of this study is to determine the rate of subsequent severe intraventricular hemorrhage (IVH), ventriculomegaly (VM), or periventricular leukomalacia (PVL) among infants < 30 weeks gestation (EGA) with a normal HUS at day of life (DOL) 4-10. METHODS: Retrospectively collected data were analyzed for all infants < 30 weeks EGA cared for in one NICU from 1 January 2010 to 31 August 2014. Infants with severe congenital anomalies were excluded. We reviewed the first three HUSs and last documented HUS. Severe IVH was defined as > Papile grade 2 and significant interval HUS change was defined as development of severe IVH, PVL, or VM. RESULTS: Of the 383 infants who had an initial screening HUS between DOL 4 and 10, 258 (67%) were initially normal and repeat screening was performed in 228 of these. None developed severe IVH on follow-up HUS. One infant developed VM secondary to GBS meningitis, and one developed echogenicity concerning for PVL that later resolved. CONCLUSIONS: Among very preterm infants with a normal HUS between DOL 4 and 10, routine follow-up HUS is unlikely to identify a significant change.