What are neuromuscular tube defects?
Neural Tube Defects (NTDs) arise secondary to abnormal embryonic development of the future central nervous system. The two most common types of NTDs are spina bifida and anencephaly, affecting different levels of the brain and spine, normally reflecting alterations of the embryonic processes that form these structures.
What is ventriculomegaly and what causes it?
Ventriculomegaly is a condition in which the brain ventricles, or fluid-filled cavities, are enlarged due to build up of cerebrospinal fluid (CSF). CSF is a fluid that protects the brain and spinal cord. The severity of ventriculomegaly depends on how enlarged the brain is.
What is the severity of ventriculomegaly?
The severity of ventriculomegaly depends on how enlarged the brain is. In some cases, fluid keeps building up, and the ventricles grow larger over time. This condition is known as hydrocephalus. Ventriculomegaly is the most common fetal brain abnormality, occurring in up to 1.5 per 1,000 pregnancies.
What is the pathogenesis of neural tube defects (NTDs)?
Neural tube defects (NTDs) are the second most common congenital malformations in humans affecting the development of the central nervous system. Although NTD pathogenesis has not yet been fully elucidated, many risk factors, both genetic and environmental, have been extensively reported.
Is ventriculomegaly a birth defect?
The severity of ventriculomegaly depends on how enlarged the brain is. In some cases, fluid keeps building up, and the ventricles grow larger over time. This condition is known as hydrocephalus. Ventriculomegaly is the most common fetal brain abnormality, occurring in up to 1.5 per 1,000 pregnancies.
What is ventriculomegaly associated with?
Ventriculomegaly is defined as a width of 10 mm or greater of the lateral ventricles at the level of the atria (Fig. 151.4). It is associated with an increased risk of aneuploidy, including Down syndrome.
Should I worry about mild ventriculomegaly?
After a complete evaluation, if the ventriculomegaly is mild and isolated, the outcome is most commonly normal. With isolated moderate ventriculomegaly of 13–15 mm, after a complete evaluation, the outcome is likely to be favorable, but there is an increased risk of neurodevelopmental disabilities.
Does ventriculomegaly cause brain damage?
This condition occurs in approximately one in 1,000 infants. Typically, ventriculomegaly only requires treatment if it causes hydrocephalus. Since the excessive pressure caused by the buildup of cerebrospinal fluid in hydrocephalus can lead to serious, long-term neurological damage, prompt treatment is a must.
Can babies with mild ventriculomegaly go away?
If your child has mildly enlarged brain ventricles or ventriculomegaly without other complications, the condition may resolve on its own. When hydrocephalus is more severe or progresses, timely treatment is important.
What causes ventriculomegaly in fetus?
The most common structural causes of fetal ventriculomegaly include aqueductal stenosis, Chiari malformation type II, dysgenesis of the corpus callosum, and abnormalities of the posterior fossa [13,14].
Can mild ventriculomegaly get worse?
Ventriculomegaly will significantly worsen in approximately 2-5% of cases. In many fetuses, particularly those with borderline ventriculomegaly, the condition will resolve spontaneously resulting in a normal outcome. The major factor that influences prognosis is the presence of associated abnormalities.
How often does ventriculomegaly resolve?
In approximately 30% of cases, the ventriculomegaly will improve as pregnancy progresses. In the other 50% of cases, the ventriculomegaly will remain stable. In the remaining 15% of cases, the ventriculomegaly will worsen.
How is ventriculomegaly treated in fetus?
There is no treatment before birth for fetuses with ventriculomegaly. Treatment after birth involves managing the child's symptoms. It is important during your pregnancy to get a detailed diagnosis (via detailed ultrasound, amniocentesis, and MRI) in order to determine if there are any additional problems.
How quickly does ventriculomegaly progress?
Progression of severe ventriculomegaly was significantly higher at a mean rate of 3.26 (SD 2.92) mm/week (p = 0.007). Conclusions: The majority of fetuses with mild ventriculomegaly normalized, whereas the majority of moderate cases remained stable. The rate of progression of ventriculomegaly increased with severity.
Is ventriculomegaly a disability?
Ventriculomegaly associated with abnormal findings and other structural malformations, often has an adverse prognosis, which ranges from disability (often mild) to death. However, in cases of mild isolated ventriculomegaly, there is around a 90% chance of a normal outcome.
What is considered severe ventriculomegaly?
Severe fetal ventriculomegaly (VM) is defined as an enlargement of the atria of the lateral cerebral ventricles (Vp) of greater than 15 mm.
What are the effects of enlarged ventricles in the brain?
The ventricles enlarge to handle the increased volume of CSF, thus compressing the brain from within and eventually damaging or destroying the brain tissue.
What infections can cause ventriculomegaly?
These are:Cytomegalovirus—an infection caused by a type of herpes virus.Toxoplasmosis—an infection linked to cat stool or infected food.Syphilis—a sexually transmitted infection (STI)Chickenpox.Lymphocytic choriomeningitis—a virus spread by mice (rare)
What is the difference between ventriculomegaly and hydrocephalus?
Ventriculomegaly is the term for enlarged brain ventricles, while hydrocephalus is the combination of ventriculomegaly and pressure on the brain. Because hydrocephalus and ventriculomegaly can be caused by many different things, it can be challenging to determine your baby's outcome.
What are the symptoms of ventriculomegaly in adults?
Demographics and Patient CharacteristicsCharacteristicValueHeadaches60 (76)Dysphagia2 (3)Fatigue13 (16)Vision21 (27)19 more rows•Feb 8, 2019
What are neural tube defects?
Neural Tube Defects (NTDs) arise secondary to abnormal embryonic development of the future central nervous system. The two most common types of NTDs are spina bifida and anencephaly, affecting different levels of the brain and spine, normally reflecting alterations of the embryonic processes that form these structures. Birth defects such as NTDs are relatively uncommon, with a global prevalence among live births in the US of 1 in 1200, and a worldwide prevalence ranging from 1 in 1,000 (in Europe and the Middle East) to 3–5 in 1,000 (in northern China as of 2014 with folate supplementation campaigns, bringing the prevalence down from 10 per 1,000 for years 2000–2004) ( Blencowe, Kancherla, Moorthie, Darlison, & Modell, 2018; Khoshnood et al., 2015; Liu et al., 2016; Salih, Murshid, & Seidahmed, 2014 ). Despite their public health significance, surprisingly little is known about the etiology of NTDs in humans.
When the primary defect involves failure to close just the cranial portion of the neural tube, the defect is refere?
When the primary defect involves failure to close just the cranial portion of the neural tube, the defect is refered to as exencephaly (anencephaly). The degeneration of the cerebral-neural tissues due to the destructive exposure of the brain to the intra-amniotic environment converts the exencephaly defect to anencephaly ( Golden & Harding, 2004; Timor-Tritsch, Greenebaum, & Monteagudo, 1996; Wilkins-Haug & Freedman, 1991)
What is the term for a defect that fails to fuse the posterior spinal cord?
In myelomeningocele, the developmental defect involves the failure to close the posterior spinal portion of the neural tube, more frequently the lumbar portion is the region which fails to fuse. In this defect, the meningeal sac herniates through a bony defect of the vertebral arch ( Figures 3 – 4 ). In some cases, a clear open defect that involves the spinal cord, but without a protruding meningeal sac, is defined as a myelocele. Therefore, a myelocele is an open defect without the cystic component ( Figure 3 – 4 ).
What are open defects in NTDs?
NTDs have been classically divided into open defects such as craniorachischisis, exencephaly-anencephaly and myelomeningoceles, and closed defects, including encephalocele, meningocele and spina bifida occulta ( Copp & Greene, 2013; McComb, 2015 ). In general, open defects are characterized by the external protrusion and/or exposure of neural tissue. Closed defects have an epithelial covering (either full or partial skin thickness) without exposure of neural tissue ( McComb, 2015 ). Biochemically, during pregnancy open defects are detectable due to the high levels of amniotic fluid α-fetoprotein and amniotic fluid acetylcholinesterase, whereas closed defects do not deviate from normal levels of amniotic fluid α-fetoprotein or acetylcholinesterase. Clinically, open defects trend towards having worse functional neurological outcomes in children, compared to closed defects.
What is the most severe expression of an open NTD?
Craniorachischisis is a defect of NTC that involves both the cranial and spinal portions of the neural tube ( Golden & Harding, 2004 ). It is the most severe expression of an open NTD.
What is the cystic mass in myelomeningocele?
In myelomeningocele, a cystic mass protruding though a bony defect in the vertebral arches is detectable. The size and shape of the lesion can vary significantly and may include cerebrospinal fluid drainage. The neural tissues appears translucent through the protruded meningeal sac and the neural placode, a segment of flat, non-neurulated embryonic neural tissue, is externally shown and protrudes above skin surface ( Figure 4 ). In case of myelocele the cystic mass is absent and the neural tissue is clearly detectable though the vertebral cleft and the placode is flush with the surface of the skin ( Figure 4 ). The spinal cord above the defect may be distorted in position and shape, but it is not overtly malformed (John L. Emery & Lendon, 1973; Naik & Emery, 1968 ).
What is the cerebral tissue?
The residual cerebral tissue appears as an irregular mass containing vascular tissue, glia, and some neuroblasts or neurons surrounded by meninges ( Golden & Harding, 2004) although some authors failed to find neurons in the area cerebrovasculosa ( Ashwal et al., 1990 ). The overview shows a poorly structured mass consisting of blood vessels ( Figure 2) scattered with connective tissue and islets of nervous tissue including interspersed astroglial cells, nerve cells, and cavities surrounded by the epithelium ( Anand et al., 2015 ). The exposed cerebral area is covered by non-keratinising squamous epithelium that laterally is continuous with epidermis ( Figure 2) ( Golden & Harding, 2004 ). Interestingly, even though there is a severe rostral neural tube abnormality, the spinal cord in the anencephalic foetuses appears structurally normal ( Anand et al., 2015 ).
Objective
To determine if the evaluation of the fetal ventricular system and hindbrain herniation (HBH) is associated with motor outcome at birth in prenatally repaired open neural tube defect (NTD).
Methods
Retrospective cohort study of 47 patients with NTD who underwent prenatal repair (17 fetoscopic; 30 open-hysterotomy). At referral and 6 weeks postoperatively, the degree of HBH, ventricular atrial widths and ventricular volume were evaluated by MRI.
Results
26% (12/47) of the cases showed worse functional level than anatomical level at birth. Having a HBH below C1 at the time of referral was associated with a worse functional level than anatomical level at birth (OR = 9.7, CI95 [2.2–42.8], p < 0.01). None of the other brain parameters showed a significant association with motor outcomes at birth.
Conclusions
HBH below C1 before surgery was associated with a worse functional level than anatomical level at birth.
Objective
To determine if the evaluation of the fetal ventricular system and hindbrain herniation (HBH) is associated with motor outcome at birth in prenatally repaired open neural tube defect (NTD).
Methods
Retrospective cohort study of 47 patients with NTD who underwent prenatal repair (17 fetoscopic; 30 open-hysterotomy). At referral and 6 weeks postoperatively, the degree of HBH, ventricular atrial widths and ventricular volume were evaluated by MRI.
Results
26% (12/47) of the cases showed worse functional level than anatomical level at birth. Having a HBH below C1 at the time of referral was associated with a worse functional level than anatomical level at birth (OR = 9.7, CI95 [2.2–42.8], p < 0.01). None of the other brain parameters showed a significant association with motor outcomes at birth.
Conclusions
HBH below C1 before surgery was associated with a worse functional level than anatomical level at birth.
