IFMSS 2019 Techincal & Educational Innovation

Aqueductal stenosis is associated with poor neurologic outcomes

In the 1980s fetal shunting for hydrocephalus was attempted but failed because accurate diagnosis of pressure hydrocephalus was not possible, leading to shunts being placed in babies with hydranencephaly, Dandy-Walker malformation, and other anomalies

When the 1980s shunting data are scrutinized, babies who had aqueductal stenosis on postnatal evaluation actually benefited from shunting

IFMSS put a moratorium on fetal shunting in 1986

Current management of fetal aqueductal stenosis is observation until near term (37 weeks) followed by assisted delivery, usually by cesarean section, sometimes classical cesarean with vertical skin incision due to large head size

The research team developed an animal model that reliably and reproducibly generates mid-trimester hydrocephalus and designed a shunt device from scratch that is near design freeze

Decompressing intracranial pressure with a shunt will allow the fetal brain to continue to develop normally and heal from injury that has already occurred

The research agenda presented in 2014 at IFMSS received phenomenal support from the investigators who instituted the 1986 moratorium, including Mike Harrison and Bill Kluwell

The hydrocephalus shunt is purpose-designed specifically for fetuses, which is very unique in fetal medicine where devices are usually borrowed from other applications

During in utero and postnatal spina bifida repair, it is very frequent not to have enough skin or dura for recovery of the lesions, requiring use of dural patches or substitutes

Many dural substitute materials exist on the market but none is demonstrated to be ideal for spina bifida repair

The Cincinnati team developed a patch using a blend of two FDA-cleared polymers (PEA-PCL) that is thin, can be coiled by body temperature, displays and uncoils automatically, is biodegradable, non-toxic, and spinal cord friendly

The PEA-PCL patch is an acellular synthetic patch that disappears around one year and does not need to be removed

The patch development timeline from concept to market readiness is approximately 5 years, starting with in vitro testing, then in vivo testing in rats, then in fetal lambs

During twin-twin transfusion syndrome laser ablation, the procedure is limited by a very limited field of view, making it hard for the surgeon to orient and navigate to find anastomoses

The Radboud team is creating a real-time panoramic view of the placental surface (a 'Google Maps for fetal surgery') to help surgeons make decisions and reduce complications associated with prolonged or incomplete surgery

The panoramic imaging algorithm uses only the visual information from the standard fetoscope without requiring extra hardware or sensors, similar to panoramic view on a phone camera

The panoramic imaging software could potentially work with any standard fetoscopy equipment and could be applied to other disciplines like bronchoscopy or laparoscopy

Fetoscopic spina bifida repair has many technical challenges in planning, preparation, and team training

The Johns Hopkins team developed a modular 3D printing system to create patient-matched models for practice before each individual spina bifida case

The 3D-printed models show very good visual correlation with the lesion at surgery and very high correlation with the number of sutures and how the repair actually goes

The modular 3D printing system is very cheap and efficient, suitable for rapid prototyping that anyone can easily incorporate into clinical practice

The workflow from ultrasound volume to 3D print takes a little over half an hour on a desktop printer, and surgical rehearsal is done with the core team within the week before surgery

The rapid print uses standard ABS filament (hard material) or Ninja Flex (soft and flexible material)

The team is close to completing standardization of the different components and has added features to the host model to make skin covering application easier and add the instability experienced in the OR