Neonatal brain injury: imaging [Short Oral Session]

A nice detail first: the chairs were a mentor–mentee pair from the society’s mentoring programme. The programme pairs established and early-career researchers to co-write papers and co-chair sessions, and it is always looking for new mentors.

This summary covers three abstracts.

1. Cerebral sinovenous thrombosis (CSVT) in preterm infants: risk factors and imaging patterns

Bregje van Oldenmark (Netherlands) – NEO-O-012, European multicentre case-control study

Why it matters: Preterm CSVT is probably more common than we think. In a German nationwide study, about one-third of neonatal CSVT cases were preterm. One single centre that routinely scans all infants born before 29 weeks found 4.4%. Despite this, preterm CSVT is poorly characterised. Earlier outcome studies could not separate the effect of CSVT from the effect of prematurity, because they had no matched controls.

The study: A matched case-control study run with European centres expert in cranial ultrasound (CUS). The presenter described it as the largest preterm CSVT cohort to date.

Findings:

• Who and when: Median gestational age around 30 weeks. Median day of diagnosis was after the second week of life.

• How it was found: More than half of cases were found on routine CUS, reflecting how many cases had no symptoms.

• Imaging: The transverse sinus was most often involved, and 60% of infants had more than one sinus affected. Periventricular white matter injury was a common accompanying finding.

• Risk factors: Perinatal and delivery-room factors did not differ between cases and controls; the differences were all postnatal. Cases more often had:

  • invasive ventilation or inotropic support

  • sepsis or meningitis

  • surgery

• After multivariable analysis, cardiorespiratory support and neonatal inflammation remained independent risk factors.

• Severe illness score: 64% of cases had at least one item in a composite “severe neonatal illness” score. Each additional item raised the odds about eightfold.

• Treatment: About two-thirds of infants received anticoagulation (LMWH). Treatment started a median of 1 day after diagnosis and lasted about 7 weeks. No haemorrhage progression or bleeding complications were seen after treatment, including in infants with pre-existing intracranial haemorrhage.

• Outcome:

  • Mortality was significantly higher in the CSVT group.

  • Among 15 survivors followed up, 4 had neurodevelopmental impairment (3 mild) and 1 developed epilepsy.

Two illustrative cases:

• Good outcome: An asymptomatic 29-weeker had a thrombus in the superior sagittal sinus found on routine CUS at day 14. The infant was treated with LMWH, the sinus had fully recanalised by term-equivalent age, and development was normal at follow-up.

• Poor outcome: A 26-weeker had sudden deterioration at 5 weeks, with apnoeas and motor agitation. Imaging showed extensive deep venous CSVT with bilateral IVH and white matter injury. Care was redirected.

Detection is improving: Case numbers rose in the second half of the study period, as did the share first detected on CUS. About 80% of cases came from only three centres. This suggests we are getting better at spotting CSVT, and that earlier cases were probably missed. A prospective, low-effort worldwide registry is being built to estimate the true incidence.

Q&A: Treatment practice varies between centres. Some anticoagulate infants below 3 weeks of age and some do not. Non-treatment was usually explained by very severe lesions or extreme prematurity.

Take-home: Preterm CSVT is mostly a disease of the sick preterm infant (ventilation, inotropes, inflammation, surgery). It is often silent. Look for the sinuses on routine CUS using the anterior fontanelle and mastoid windows with colour Doppler, and keep a “normal” reference image for each patient. Even without Doppler, a thrombus often stands out as an echogenic spot, but only if you have something to compare it with.

2. Brain injury and short-term outcomes after single fetal demise in monochorionic twins

Mathies Rondagh (Netherlands) – NEO-O-013, international multicentre retrospective study

Background: After the death of one monochorionic twin, the surviving co-twin can acutely exsanguinate into the low-pressure circulation of the dead twin. This happens through placental anastomoses, mainly arterio-arterial (AA) and veno-venous (VV). The result can be acute fetal anaemia, hypoperfusion and hypoxic-ischaemic brain injury.

The study:

• 13 fetal therapy centres, covering 2000–2025.

• 395 monochorionic pregnancies with single fetal demise (sIUFD) and available neuroimaging (fetal or neonatal ultrasound and MRI).

• Excluded:

  • demise after laser for TTTS, since the coagulated placenta carries no exsanguination risk

  • selective feticide

  • TAPS, which has only tiny anastomoses

  • major congenital anomalies

Findings:

• Median gestational age at sIUFD: 22.7 weeks.

• Severe brain injury in 18% (about one in five) of surviving co-twins.

• Co-twin demise occurred in 10% of pregnancies. Termination occurred in 9%, mostly because of severe brain injury.

• When MCA-PSV was measured, fetal anaemia was found in 43%, and 12% received intrauterine transfusion.

• The injury pattern was consistent with acute hypoxic-ischaemic injury after exsanguination. Non-cystic white matter injury was the most common finding, followed by ischaemic infarction and cystic PVL.

• Timing of injury: 82% antenatal, 5% perinatal, 10% postnatal, and 2 cases undetermined.

• Independent risk factors (multivariable):

  • each additional week of gestation at sIUFD

  • fetal anaemia within 2 weeks of sIUFD

  The proposed explanation is that AA and VV anastomoses grow with gestation, so a later demise allows a larger, faster transfusion into the dead twin.

• Interval from demise to birth: An interval under 4 weeks was associated with more neonatal death, severe brain injury and neonatal morbidity. Confounding by indication is likely. The median interval was 11.6 weeks, with large variation between centres.

Q&A: Injury was called “postnatal” when fetal MRI 4–6 weeks after the demise was normal and later imaging evolved accordingly. The authors propose a “triple hit” model:

1. the underlying monochorionic complication (sFGR or TTTS)

2. the acute exsanguination itself

3. prematurity

This makes causality hard to establish. Earlier fetal MRI looks promising for counselling and decision-making, and is a planned future study. For now, the authors support current guidance of fetal MRI 4–6 weeks after demise.

Take-home: About 1 in 5 surviving monochorionic co-twins has severe brain injury, and it is mostly antenatal. Image both antenatally and postnatally. Immediate delivery after sIUFD does not prevent brain injury, because the acute event has already happened, and it adds the risks of prematurity. In a clinically stable pregnancy, the advice is against immediate delivery, in line with obstetric society recommendations.

3. Validating the Kidokoro MRI score and a simplified version for predicting neurodevelopment in very preterm infants

Carmen Rodriguez Barrios (Spain) – NEO-O-014

Background: The Kidokoro score (2013) grades brain abnormality on term-equivalent MRI in very preterm infants. It covers four domains: cerebral white matter, cortical grey matter, deep grey matter and cerebellum. It is predictive, but many items make it cumbersome in routine practice.

The study:

• Single-centre cohort of very preterm infants with term-equivalent MRI.

• 260 had complete scores and 180 had Bayley assessment at 2 years corrected age.

• Mean gestational age about 29 weeks; mean birth weight about 1180 g.

• 24% had an adverse outcome, defined by a threshold on any Bayley domain.

Original score:

• Internal consistency was high (Cronbach’s α), and no single item improved α when removed.

• Exploratory factor analysis showed one dominant factor, supporting a single global severity construct.

• Discrimination per Bayley domain was moderate (AUC 0.68–0.79).

Simplified score: Selected by all-possible-subsets regression. It uses gestational age plus five MRI features. Items are weighted by prognostic importance; for example, cystic lesions score 0/2/4/6/8, while corpus callosum thinning scores 0/1/2.

• Outcome by category:

• Each additional point raised the odds of adverse outcome by about 23%, and higher scores were linked to worse scores in all three Bayley domains.

• Comparison with the original score:

None of these differences was significant, so simplifying the score did not cost discrimination.

• Validation: Internal (split-sample and 5-fold cross-validation). Inter-rater reliability was excellent.

• Next steps: Test–retest reliability and external multicentre validation.

Take-home: A five-item, weighted MRI score plus gestational age predicts 2-year outcome as well as the full Kidokoro score, and is much quicker to use at the bedside. It needs external validation before wide adoption.

Disclosure: This is an AI-assisted summary of the session, generated from a recording made by our team in attendance. We believe it is as accurate as our own notes would be, but please refer to the speakers’ original work before applying anything in clinical practice.