Prenatal Evaluation of Intracranial Hemorrhage on Fetal MRI: A Retrospective Review

Prenatal sonographic diagnosis and postnatal outcomes of fetal intracranial hemorrhage: Two case report

Intracranial hemorrhage (ICH) in pregnancy, estimated at 1 in 10,000 cases, presents significant diagnostic challenges prenatally despite advanced imaging techniques such as ultrasonography (US) and magnetic resonance imaging (MRI). Detecting ICH is crucial for pregnancy management and future treatment decisions aimed at improving fetal survival and reducing brain damage. This report presents the diagnosis and outcomes of 2 cases of prenatal ICH. The first case involves a 30-year-old pregnant woman with irregular prenatal care diagnosed with ICH at 32 weeks of gestation via US and MRI. She chose to continue the pregnancy, delivering a 3160 g male infant at 36 weeks via cesarean section. Following NICU care including resuscitation and ventriculoperitoneal shunt placement, the infant was discharged. Subsequent examinations showed a reduction in ventricle size. In the second case, a 27-year-old woman taking acenocoumarol for a mechanical heart valve developed fetal subdural hemorrhage detected by US and MRI. She opted to terminate the pregnancy, resulting in a stillborn male infant weighing 1530 g. Fetal ICH presents with varying severity and prognostic implications, diagnosed and graded using US. Fetal cranial MRI may help clarify the etiology. Management remains controversial, with termination of pregnancy potentially warranted in severe cases due to poor prognosis. Further research is needed to refine management and improve outcomes in fetal ICH.

Fully automated planning for anatomical fetal brain MRI on 0.55T

PURPOSE

Widening the availability of fetal MRI with fully automatic real-time planning of radiological brain planes on 0.55T MRI.

METHODS

Deep learning-based detection of key brain landmarks on a whole-uterus echo planar imaging scan enables the subsequent fully automatic planning of the radiological single-shot Turbo Spin Echo acquisitions. The landmark detection pipeline was trained on over 120 datasets from varying field strength, echo times, and resolutions and quantitatively evaluated. The entire automatic planning solution was tested prospectively in nine fetal subjects between 20 and 37 weeks. A comprehensive evaluation of all steps, the distance between manual and automatic landmarks, the planning quality, and the resulting image quality was conducted.

RESULTS

Prospective automatic planning was performed in real-time without latency in all subjects. The landmark detection accuracy was 4.2± $$ \pm $$ 2.6 mm for the fetal eyes and 6.5± $$ \pm $$ 3.2 for the cerebellum, planning quality was 2.4/3 (compared to 2.6/3 for manual planning) and diagnostic image quality was 2.2 compared to 2.1 for manual planning.

CONCLUSIONS

Real-time automatic planning of all three key fetal brain planes was successfully achieved and will pave the way toward simplifying the acquisition of fetal MRI thereby widening the availability of this modality in nonspecialist centers.

Fetal Intraparenchymal Hemorrhage Imaging Patterns, Etiology, and Outcomes: A Single Center Cohort Study

OBJECTIVE

This study examines associations among fetal brain magnetic resonance imaging (MRI) injury patterns, etiologies, and outcomes in fetal intraparenchymal hemorrhage (IPH).

METHODS

This is a retrospective, single-center cohort study of IPH diagnosed on fetal MRI (1996-2022). IPH and associated abnormalities were categorized by 2 pediatric neuroradiologists; electronic medical records were reviewed by 2 pediatric neurologists to classify etiology and outcomes including cerebral palsy, epilepsy, developmental delay, and death.

RESULTS

Forty-four fetuses with IPH were identified (34 singleton and 10 twin gestations) with MRI at median 24 weeks gestation (interquartile range [IQR] = 22-28 weeks). IPH was commonly supratentorial (84%) and focal (50%) or focal with diffuse injury (43%) and was often associated with germinal matrix hemorrhage (GMH; 75%) and/or intraventricular hemorrhage (IVH; 52%). An etiology was identified in 75%, including twin-twin transfusion syndrome (TTTS, n = 10), COL4A1/2 variants (n = 8), or other fetal/maternal conditions (n = 15). COL4A1/2 variants were associated with focal IPH and the presence of hemorrhagic porencephaly, and intrauterine transfusion was associated with infratentorial hemorrhage. Twenty-two fetuses were liveborn, and 18 pregnancies were terminated. Among those with follow-up ≥ 12 months (median = 7 years), 12 of 13 had cerebral palsy, 6 of 13 had developmental delay, and 5 of 13 had epilepsy.

INTERPRETATION

An etiology for fetal IPH with or without GMH-IVH is identified in most cases in our cohort and is commonly TTTS, COL4A1/2 variants, or other maternal/fetal comorbidities. Pattern of fetal IPH on MRI is associated with etiology. Cerebral palsy and neurodevelopmental impairment were common in liveborn infants. Genetic studies should be considered in cases of fetal IPH without an otherwise apparent cause. ANN NEUROL 2024.

Isolated Fetal Ventriculomegaly: Diagnosis and Treatment in the Prenatal Period

Fetal ventriculomegaly (VM) is a defect of the central nervous system, typically diagnosed during the second-trimester ultrasound in fetuses with an atrial diameter (AD) of >10 mm. Non-isolated ventriculomegaly (NIVM) is heterogeneous in nature, coexisting with additional intracranial and/or extracranial malformations and genetic syndromes, resulting in an unfavorable prognosis for the further development of the child. Both the pregnancy management and counseling are dependent on the findings of combined ultrasound/MRI, genetic testing, and gestational age at diagnosis. The purpose of this review is to propose a hypothesis that diagnostic advancements allow to define the process of identification of the isolated forms of VM (IVM). Based on the evidence presented in the literature, we consider whether prenatal decompression for severe isolated VM (ISVM) is supported by the experimental trials and whether it might be implemented in clinical practice. Also, we describe the evolution of the diagnostic methods and expert opinions about the previously used prenatal decompression techniques for ISVM. In conclusion, we introduce the idea that fetal surgery centers have either reached or nearly reached the necessary level of expertise to perform such procedures. Endoscopic cystoventriculostomy (ETV) appears to be the most promising, as it is associated with minimal perinatal complications and favorable neurological outcomes in the neonatal period. Randomized trials with long-term neurodevelopmental follow-up of children who underwent prenatal decompression due to ISVM are necessary.

Imaging Fetal Spine Malformations in the Context of In Utero Surgery

This review covers the embryology, definition, and diagnosis of open spinal dysraphism with a focus on fetal ultrasound and MR imaging findings. Differentiating open versus closed spinal dysraphic defects on fetal imaging will also be discussed. Current fetal surgery practices and imaging findings in the context of fetal surgery are also reviewed.

Prenatal diagnosis and postnatal outcome of fetal intracranial hemorrhage: a single-center experience

OBJECTIVE

To assess prenatal ultrasonographic findings and postnatal outcomes in fetuses with intracranial hemorrhage (ICH).

METHODS

This retrospective study included fetuses prenatally diagnosed with ICH between December 2012 and August 2023. Maternal characteristics, prenatal ultrasonographic findings, and postnatal outcomes were reviewed.

RESULTS

Twenty-seven fetuses with ICH were reviewed. Intracranial hemorrhage was classified as grade 3 and 4 in 24 fetuses. Twenty-two fetuses had ICH, four had ICH with subdural hemorrhage, and one had ICH with subarachnoid hemorrhage. Ventriculomegaly was the most common ultrasonographic finding, and was observed in 22 of the 27 (81.5%) fetuses. Seven fetuses were lost to follow-up, and four intrauterine fetal deaths occurred. The remaining 16 fetuses were delivered at a median gestational age of 35+2 weeks. The infants were followed-up for 40.1 months (range, 4-88). Nine of the 16 infants underwent ventriculoperitoneal placement. One infant underwent brain surgery for severe epilepsy. Motor impairment, including cerebral palsy, was observed in 13 infants (81.2%). Neurologic impairment occurred in six infants (37.5%), developmental delay in nine (56.2%), and epilepsy in 11 (68.7%).

CONCLUSION

Fetal ICH is a rare complication diagnosed during pregnancy, which results in subsequent fetal neurological sequelae or death. This study demonstrated that the common ultrasonographic findings in fetal ICH were progressive ventriculomegaly and increased periventricular echogenicity. Fetuses diagnosed with prenatal ICH, especially those affected by higher-grade ICH, may be at an increased risk of long-term neurodevelopmental problems.

Prenatal diagnosis of cerebellar hemorrhage: A case report

We report the case of a fetus with a sonographic diagnosis of hyperechogenic cerebellum at 28 weeks' gestation, which was suspected to be of hemorrhagic origin on fetal ultrasound. As an adjunct to ultrasound, fetal MRI can confirm the hemorrhagic origin of hyperechogenic cerebellar lesions, particularly by showing a high signal on T1-weighted images. No etiological factors for fetal hemorrhage were found other than maternal hypertension and aspirin use. Postnatal MRI confirmed the prenatal diagnosis of cerebellar hemorrhage without underlying vascular anomaly.

Automatic Quantification of Normal Brain Gyrification Patterns and Changes in Fetuses with Polymicrogyria and Lissencephaly Based on MRI

BACKGROUND AND PURPOSE

The current imaging assessment of fetal brain gyrification is performed qualitatively and subjectively using sonography and MR imaging. A few previous studies have suggested methods for quantification of fetal gyrification based on 3D reconstructed MR imaging, which requires unique data and is time-consuming. In this study, we aimed to develop an automatic pipeline for gyrification assessment based on routinely acquired fetal 2D MR imaging data, to quantify normal changes with gestation, and to measure differences in fetuses with lissencephaly and polymicrogyria compared with controls.

MATERIALS AND METHODS

We included coronal T2-weighted MR imaging data of 162 fetuses retrospectively collected from 2 clinical sites: 134 controls, 12 with lissencephaly, 13 with polymicrogyria, and 3 with suspected lissencephaly based on sonography, yet with normal MR imaging diagnoses. Following brain segmentation, 5 gyrification parameters were calculated separately for each hemisphere on the basis of the area and ratio between the contours of the cerebrum and its convex hull. Seven machine learning classifiers were evaluated to differentiate control fetuses and fetuses with lissencephaly or polymicrogyria.

RESULTS

In control fetuses, all parameters changed significantly with gestational age (P < .05). Compared with controls, fetuses with lissencephaly showed significant reductions in all gyrification parameters (P ≤ .02). Similarly, significant reductions were detected for fetuses with polymicrogyria in several parameters (P ≤ .001). The 3 suspected fetuses showed normal gyrification values, supporting the MR imaging diagnosis. An XGBoost-linear algorithm achieved the best results for classification between fetuses with lissencephaly and control fetuses (n = 32), with an area under the curve of 0.90 and a recall of 0.83. Similarly, a random forest classifier showed the best performance for classification of fetuses with polymicrogyria and control fetuses (n = 33), with an area under the curve of 0.84 and a recall of 0.62.

CONCLUSIONS

This study presents a pipeline for automatic quantification of fetal brain gyrification and provides normal developmental curves from a large cohort. Our method significantly differentiated fetuses with lissencephaly and polymicrogyria, demonstrating lower gyrification values. The method can aid radiologic assessment, highlight fetuses at risk, and may improve early identification of fetuses with cortical malformations.

Pregnancy and Child Outcomes Following Fetal Intracranial Hemorrhage

BACKGROUND

The prenatal and early postnatal outcomes of fetal intracranial hemorrhage (ICH) prenatally diagnosed by fetal magnetic resonance imaging (MRI) have not been well described.

METHODS

A retrospective study of cases with fetal ICH diagnosed by fetal MRI at Children's National Hospital, Washington, DC, from 2012 to 2020 was conducted. Maternal characteristics, prenatal imaging, pregnancy outcome, and child developmental outcomes were recorded. Abnormal outcomes were categorized as mild for required physical/occupational therapy without other delays, moderate for intermediate multidomain developmental delays, and severe if nonambulatory, nonverbal, or intellectual disability.

RESULTS

Fifty-seven cases with fetal ICH were included. The mean (S.D.) maternal age was 31.1 (6.9) years, gestational age at fetal evaluation was 28.1 (5.3) weeks, and gestational age at birth was 38.2 (1.3) weeks. Pregnancy outcomes were 75% (n = 43) live birth, 14% (n = 8) termination of pregnancy, and 11% (n = 6) intrauterine demise (IUD). Live births decreased from 90% to 33% and IUD increased 10% to 22% when comparing unilateral intraventricular hemorrhage with more extensive hemorrhages. Among the 37 live-born infants with clinical follow-up to age 1.8 (1.6) years, neurodevelopmental outcome was normal in 57%, mildly abnormal in 24%, moderately abnormal in 14%, and severely abnormal in 5%. In five cases, an etiology was identified: two had placental pathologies, two had genetic findings (fetal neonatal alloimmune thrombocytopenia and COL4A1 mutation), and one had congenital cytomegalovirus infection.

CONCLUSION

Perinatal and early child outcomes following fetal ICH have a wide spectrum of outcomes. Fetal MRI description of ICH location may aid in pregnancy and postnatal outcome prediction.

Clinical Applications of Fetal MRI in the Brain

Fetal magnetic resonance imaging (MRI) has become a widely used tool in clinical practice, providing increased accuracy in prenatal diagnoses of congenital abnormalities of the brain, allowing for more accurate prenatal counseling, optimization of perinatal management, and in some cases fetal intervention. In this article, a brief description of how fetal ultrasound (US) and fetal MRI are used in clinical practice will be followed by an overview of the most common reasons for referral for fetal MRI of the brain, including ventriculomegaly, absence of the cavum septi pellucidi (CSP) and posterior fossa anomalies.