Fetal neurosurgery: current state of the art

Prenatal politics: fetal surgery, abortion and disability rights in the United States

While fetal surgery-and pregnancy termination as a possible therapeutic alternative-have been examined in a number of studies, very few have addressed the issues and tensions that arise when prenatal surgery is considered from the standpoint of Disability Studies. This article will expose these concerns by tracing the medical development of fetal surgery; the arguments for and against prenatal surgery; and the connections between fetal surgery, abortion, and disability rights. Like other dimensions of the life cycle that involve reproduction, prenatal surgery has become highly politicized in the United States which has, to a certain extent, stalled critical discussion. However, the skepticism with which many disability rights advocates and policymakers approach prenatal medical intervention in general has opened a new space for active debate concerning fetal surgery in terms of how it medicalizes pregnancy, pathologizes diversity, contributes to the valuation of life, and emphasizes 'perfect babies' at any cost.

Use of Fetal Magnetic Resonance Image Analysis and Machine Learning to Predict the Need for Postnatal Cerebrospinal Fluid Diversion in Fetal Ventriculomegaly

IMPORTANCE

Which children with fetal ventriculomegaly, or enlargement of the cerebral ventricles in utero, will develop hydrocephalus requiring treatment after birth is unclear.

OBJECTIVE

To determine whether extraction of multiple imaging features from fetal magnetic resonance imaging (MRI) and integration using machine learning techniques can predict which patients require postnatal cerebrospinal fluid (CSF) diversion after birth.

DESIGN, SETTING, AND PATIENTS

This retrospective case-control study used an institutional database of 253 patients with fetal ventriculomegaly from January 1, 2008, through December 31, 2014, to generate a predictive model. Data were analyzed from January 1, 2008, through December 31, 2015. All 25 patients who required postnatal CSF diversion were selected and matched by gestational age with 25 patients with fetal ventriculomegaly who did not require CSF diversion (discovery cohort). The model was applied to a sample of 24 consecutive patients with fetal ventriculomegaly who underwent evaluation at a separate institution (replication cohort) from January 1, 1998, through December 31, 2007. Data were analyzed from January 1, 1998, through December 31, 2009.

EXPOSURES

To generate the model, linear measurements, area, volume, and morphologic features were extracted from the fetal MRI, and a machine learning algorithm analyzed multiple features simultaneously to find the combination that was most predictive of the need for postnatal CSF diversion.

MAIN OUTCOMES AND MEASURES

Accuracy, sensitivity, and specificity of the model in correctly classifying patients requiring postnatal CSF diversion.

RESULTS

A total of 74 patients (41 girls [55%] and 33 boys [45%]; mean [SD] gestational age, 27.0 [5.6] months) were included from both cohorts. In the discovery cohort, median time to CSF diversion was 6 days (interquartile range [IQR], 2-51 days), and patients with fetal ventriculomegaly who did not develop symptoms were followed up for a median of 29 months (IQR, 9-46 months). The model correctly classified patients who required CSF diversion with 82% accuracy, 80% sensitivity, and 84% specificity. In the replication cohort, the model achieved 91% accuracy, 75% sensitivity, and 95% specificity.

CONCLUSION AND RELEVANCE

Image analysis and machine learning can be applied to fetal MRI findings to predict the need for postnatal CSF diversion. The model provides prognostic information that may guide clinical management and select candidates for potential fetal surgical intervention.

Fetal ventriculomegaly: Diagnosis, treatment, and future directions

Fetal ventriculomegaly (VM) refers to the enlargement of the cerebral ventricles in utero. It is associated with the postnatal diagnosis of hydrocephalus. VM is clinically diagnosed on ultrasound and is defined as an atrial diameter greater than 10 mm. Because of the anatomic detailed seen with advanced imaging, VM is often further characterized by fetal magnetic resonance imaging (MRI). Fetal VM is a heterogeneous condition with various etiologies and a wide range of neurodevelopmental outcomes. These outcomes are heavily dependent on the presence or absence of associated anomalies and the direct cause of the ventriculomegaly rather than on the absolute degree of VM. In this review article, we discuss diagnosis, work-up, counseling, and management strategies as they relate to fetal VM. We then describe imaging-based research efforts aimed at using prenatal data to predict postnatal outcome. Finally, we review the early experience with fetal therapy such as in utero shunting, as well as the advances in prenatal diagnosis and fetal surgery that may begin to address the limitations of previous therapeutic efforts.

Fetal Therapy for Isolated Aqueductal Stenosis

Aqueductal stenosis (AS) is a form of noncommunicating hydrocephalus, which causes increased intracranial pressure secondary to obstruction of the aqueduct of Sylvius. Relief of intracranial pressure in the fetus by ventriculoamniotic shunting may diminish or even prevent permanent neurologic injury. Shunting was attempted in the 1980s but was abandoned due to technical difficulties. Given the advances in prenatal diagnosis and fetal intervention over the last 3 decades, we believe that an evidence-based reevaluation of the option is timely and appropriate. The aim of this review article is to discuss the clinical significance of the diagnosis of AS, current management strategies, current diagnostic capabilities, new shunt technology, and barriers to progress. Finally, we will advance a research agenda that will provide evidence-based management recommendations.

Early gestation chorionic villi-derived stromal cells for fetal tissue engineering

AIM: To investigate the potential for early gestation placenta-derived mesenchymal stromal cells (PMSCs) for fetal tissue engineering.

METHODS: PMSCs were isolated from early gestation chorionic villus tissue by explant culture. Chorionic villus sampling (CVS)-size tissue samples (mean = 35.93 mg) were used to test the feasibility of obtaining large cell numbers from CVS within a clinically relevant timeframe. We characterized PMSCs isolated from 6 donor placentas by flow cytometry immunophenotyping, multipotency assays, and through immunofluorescent staining. Protein secretion from PMSCs was examined using two cytokine array assays capable of probing for over 70 factors in total. Delivery vehicle compatibility of PMSCs was determined using three common scaffold systems: fibrin glue, collagen hydrogel, and biodegradable nanofibrous scaffolds made from a combination of polylactic acid (PLA) and poly(lactic-co-glycolic acid) (PLGA). Viral transduction of PMSCs was performed using a Luciferase-GFP-containing lentiviral vector and efficiency of transduction was tested by fluorescent microscopy and flow cytometry analysis.

RESULTS: We determined that an average of 2.09 × 10⁶ (SD ± 8.59 × 10⁵) PMSCs could be obtained from CVS-size tissue samples within 30 d (mean = 27 d, SD ± 2.28), indicating that therapeutic numbers of cells can be rapidly expanded from very limited masses of tissue. Immunophenotyping by flow cytometry demonstrated that PMSCs were positive for MSC markers CD105, CD90, CD73, CD44, and CD29, and were negative for hematopoietic and endothelial markers CD45, CD34, and CD31. PMSCs displayed trilineage differentiation capability, and were found to express developmental transcription factors Sox10 and Sox17 as well as neural-related structural proteins NFM, Nestin, and S100β. Cytokine arrays revealed a robust and extensive profile of PMSC-secreted cytokines and growth factors, and detected 34 factors with spot density values exceeding 10³. Detected factors had widely diverse functions that include modulation of angiogenesis and immune response, cell chemotaxis, cell proliferation, blood vessel maturation and homeostasis, modulation of insulin-like growth factor activity, neuroprotection, extracellular matrix degradation and even blood coagulation. Importantly, PMSCs were also determined to be compatible with both biological and synthetic material-based delivery vehicles such as collagen and fibrin hydrogels, and biodegradable nanofiber scaffolds made from a combination of PLA and PLGA. Finally, we demonstrated that PMSCs can be efficiently transduced (> 95%) with a Luciferase-GFP-containing lentiviral vector for future in vivo cell tracking after transplantation.

CONCLUSION: Our findings indicate that PMSCs represent a unique source of cells that can be effectively utilized for in utero cell therapy and tissue engineering.

Attitude of expectant mothers on the use of ultrasound in pregnancy in a tertiary institution in South East of Nigeria

Background:

With the world-wide availability of ultrasound services even in the developing countries, routine ultrasonography in pregnancy remains a controversial issue. However, in this era of reproductive health right and evidence-based medicine, the views of women need to be ascertained.

Aims:

The aim is to assess the attitude of antenatal women toward sonography in pregnancy.

Subjects and Methods:

A descriptive self-administered questionnaire-based cross-sectional study using 208 women that booked for antenatal care from January 1, 2009 to June 30, 2009 at the University of Nigeria Teaching Hospital, Enugu.

Results:

The number of respondents who had ultrasonography in their previous pregnancies was 58.7% (122/208). Although many reasons were given for personal ultrasound requests, 19.7% (24/122) of the women who had obstetric scan in their previous pregnancies thought it was a normal booking test done for every pregnant woman. When compared with other booking investigations, 60.1% (125/208), mainly civil servants .expressed the views that ultrasound in pregnancy is costly, while 24.4% (59/208) felt it is cheap, 9.1% (19/208) said it is very costly, while the remaining 2.4% (5/208) thought it is not affordable. Apart from visualizing the images of their babies, 17.8% (37/208) of the cases wanted to know the sexes of their babies while 15.4% (32/208) was for determination of fetal position. Out of 110, 52.9% (110/208) were of the opinion that women can decide when to request for sonography.

Conclusion:

The attitude of Nigerian women to sonography is good. Majority of them request ultrasound for fetal observation and gender determination.

Alterations in maternal-fetal cellular trafficking after fetal surgery

BACKGROUND/PURPOSE

Bidirectional trafficking of cells between the mother and the fetus is routine in pregnancy and a component of maternal-fetal tolerance. Changes in fetal-to-maternal cellular trafficking have been reported in prenatal complications, but maternal-to-fetal trafficking has never been studied in the context of fetal intervention. We hypothesized that patients undergoing open fetal surgery would have altered maternal-fetal cellular trafficking.

METHODS

Cellular trafficking was analyzed in patients with myelomeningocele (MMC) who underwent open fetal surgical repair (n = 5), patients with MMC who had routine postnatal repair (n = 6), and healthy control healthy patients (n = 9). As an additional control for the fetal operation, trafficking was also analyzed in patients who were delivered by an ex utero intrapartum treatment procedure (n = 6). Microchimerism in maternal and cord blood was determined using quantitative real-time polymerase chain reaction for nonshared alleles.

RESULTS

Maternal-to-fetal trafficking was significantly increased in patients who underwent open fetal surgery for MMC compared with healthy controls, patients who underwent postnatal MMC repair, and patients who underwent ex utero intrapartum treatment. There were no differences in fetal-to-maternal cell trafficking among groups.

CONCLUSION

Patients undergoing open fetal surgery for MMC have elevated levels of maternal microchimerism. These results suggest altered trafficking and/or increased proliferation of maternal cells in fetal blood and may have important implications for preterm labor.