|Year : 2022 | Volume
| Issue : 2 | Page : 110-112
Case series of cranial and spinal dysraphism
Gayathri Pandurangam1, D Nagajyothi2, Seethamsetty Saritha3, Asra Anjum4
1 Assistant Professor, Department of Respiratory Care, College of Applied Medical Sciences in Jubail, Imam Abdulrahman Bin Faisal University, Saudi Arabia
2 Assistant Professor, Department of Anatomy, Government Medical College, Nalgonda, Telangana, India
3 Professor and Head, Department of Anatomy, Kamineni Academy of Medical Sciences and Research Centre, Hyderabad, Telangana, India
4 Tutor, Department of Anatomy, Mamata Academy of Medical Sciences, Hyderabad, Telangana, India
|Date of Submission||05-Sep-2021|
|Date of Decision||06-Apr-2022|
|Date of Acceptance||19-Apr-2022|
|Date of Web Publication||26-May-2022|
Assistant Professor, Department of Respiratory Care, College of Applied Medical Sciences in Jubail, Imam Abdulrahman Bin Faisal University
Source of Support: None, Conflict of Interest: None
Neural tube defects (NTDs) are the second most common cause of congenital anomaly worldwide (cardiac anomalies is the first). The 3rd and 4th week of gestation is the critical period for neural tube development. Multiple genetic and environmental factors are known to cause the NTDs in a developing embryo. We report here four cases of cranial and spinal dysraphism or craniorachischisis, the most severe and rare type of NTD with brief maternal history. In all these cases, the neural tissue is exposed in the region of brain as well as in the region of spinal cord to various extents. In this case series, the external features of craniorachischisis in four female fetuses (including monozygotic twins) are reported. One of the affected fetuses had associated omphalocele.
Keywords: Anencephaly, craniorachischisis, dysraphism, neural tube defect, neurulation
|How to cite this article:|
Pandurangam G, Nagajyothi D, Saritha S, Anjum A. Case series of cranial and spinal dysraphism. Natl J Clin Anat 2022;11:110-2
| Introduction|| |
Although prenatal diagnosis and screening are much advanced, congenital anomalies especially cardiac system and central nervous system (CNS) malformations amount to majority of pediatric conditions. Neural tube defect (NTD) is one of the most common types of congenital malformation. The term NTD refers to a wide spectrum of CNS malformation that results due to defects in the closure of neural tube such as myelomeningocele, anencephaly, encephalocele, craniorachischisis, and spina bifida. Anencephaly is the most severe form of NTD. The process of bending of neural plate and fusion to form the neural tube that later differentiates to brain and spinal cord is known as neurulation. Neurulation takes place at first in the cervical region at the fourth somite around 20th day and extends both cranially and caudally until anterior and posterior neuropore appears. NTDs result due to failure in this rolling and sealing process of neural tube., When posterior neural ectoderm and cutaneous ectoderm continues persistently, it is called dysraphism. The defect is limiting to the cranium known as cranial dysraphism, and this includes anencephaly and encephaloceles. In craniorachischisis, the cranial dysraphism is continuous below associated with fissure in spine (spinal dysraphism), resulting in exposed neural tissue in the region of spine. The spinal dysraphism can be seen extending until cervical, thoracic, or lumbar region depending on the severity. When the spinal defect extends throughout the vertebral column, it is known as craniorachischisis totalis.
Conceptus with anencephaly usually does not survive, and those associated with lesser degree of NTD may be associated with multiple CNS abnormalities –lack of functioning cerebrum and rudimentary brainstem, which in turn result in blindness and deafness. The objective of this evaluation was to describe the cases available with NTDs having cranial and spinal dysraphism.
| Materials and Methods|| |
Study design and conceptus
A descriptive, retrospective study by reviewing 100 stillborn fetuses and abortuses over a period of 2 years available from the Obstetrics Department of Kamineni Academy of Medical Sciences and Research Centre, Hyderabad. Only those specimens where proper gestational history, prenatal diagnosis, and termination of pregnancy history are known were included.
Demographic characteristics, obstetric history, symptoms, prenatal scan details, folic acid supplementation details, and any genetic tests done were noted. External morphology of each fetus affected with cranial and spinal dysmorphism were also studied. All fetuses were formalin fixed and mounted. No attempts were made to dissect and delineate the internal malformations. Each fetus is photographed in the anterior and posterior view, and morphological features are presented.
The study was reviewed by the institutional review board and approved by the ethical committee, with the registration number ECR/58/Inst/AP/2013/RR-16.
Fetus 1: Female fetus 23–24 weeks with craniorachischisis totalis
A 24-year-old primigravida presented with a history of consanguineous marriage and poor socioeconomic status. She was an unbooked case with no history of intake of supplemental folic acid. Antenatal scan revealed conceptus with anencephaly, and pregnancy was terminated medically. The fetus was seen to have abnormally bulging eyes with absent neck. Defect in the scalp is seen extending up to the upper thoracic vertebrae. Brain tissue and spinal cord in the cervical and thoracic region were exposed (until lumbar region) with spinal nerve roots. Normal skin was seen covering the rest of the vertebral column [Figure 1].
|Figure 1: Craniorachischisis in fetus of 23–25 weeks. (a) Anterior view showing anencephaly, bulging eyes, and absent neck. (b) Posterior view showing skull defect, unfused vertebrae, and exposed spinal nerves|
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Fetus 2: Female fetus 18 weeks with craniorachischisis and associated omphalocele
A 25-year-old primigravida, nonconsanguineous marriage presented with a history of folic acid intake after the confirmation of pregnancy at 5 weeks of gestation. Ultrasound examination revealed anterior abdominal wall defect; hence, pregnancy was terminated. A female fetus of 18 weeks gestation with craniorachischisis associated with omphalocele was delivered. The intestinal loops were seen protruding through the abdominal defect in the sac observed outside the abdominal wall. Craniorachischisis extending up to the lumbar region was noted. Mother's blood sample was positive for methylenetetrahydrofolate reductase (MTHFR) C677T mutation [Figure 2].
|Figure 2: Craniorachischisis in female fetus of 18 weeks. (a) Anterior view showing omphalocele (Omp) containing liver and coils of small intestine. (b) Posterior view showing cranial defect and vertebral column defect until lumbar region|
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Fetuses 3 and 4: Monozygotic female twins 24 weeks with craniorachischisis
A 32-year-old women, with gestational score G2P1 L1 and consanguineous marriage, presented with no history of folic acid intake. First pregnancy was normal. Termination of pregnancy was done following the ultrasound findings of twin pregnancy with anencephaly. One of the conceptuses had craniorachischisis with anencephaly, bulging eyes, protruding tongue, webbed neck, and spinal defect extending until the lumbar region. Another conceptus had craniorachischisis with anencephaly, webbed neck, and spinal defect extending until the cervical region [Figure 3].
|Figure 3: Monozygotic twins of 24–26 weeks: (A) craniorachischisis extending up to the lumbar region, (B) craniorachischisis extending up to the cervical region|
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| Discussion|| |
The incidence of NTDs is 0.5–2/1000 live births worldwide. 60%–70% of affected children were females, with craniorachischisis involving cervicothoracic region of the spinal cord. Neural tube development and closure occurs during the 3rd and 4th gestational weeks, and closure of neural tube is completed 28 days postconception. Gene mutation of folic acid metabolism is one of the risk factors for NTDs, although dietary and environmental factors cannot be ruled out. Insult in the folate gene pathway usually results in midline developmental defects such as craniorachischisis with omphalocele as seen in the Fetus 2 of the present study. Other midline defects involving diaphragm, cleft palate, and cleft lip can also be seen.
Many epidemiological studies have suggested that folic acid supplementation is associated with lesser incidence of NTDs and also associated anomalies such as omphalocele., Other anomalies known to be associated with craniorachischisis are cardiovascular defects, caudal regression syndrome or syringomyelia, hypoplastic lung, and gastrointestinal atresia. In Case 2, NTD has occurred despite folic acid supplementation. Craniorachischisis was seen associated with a mediastinal bronchogenic cyst in a consanguineously married couple, in a case report by Prashant et al. Consanguinity has been implicated in increased cases of NTDs in several countries. Consanguinity was present in Case 1 and Case 2 of monozygotic twins in the present study.
Among genetic factors, processes regulating one-carbon folate metabolism and planar cell polarity are strongly considered to cause NTDs., MTHFR gene mutations C677T and A1298C are well known to be associated with increased risk for NTDs in humans. A case–control study in the Netherlands by van der Put et al. reported a mutation in C677T in 15% of spina bifida patients and also in the parents of NTD patients. The C677T mutation/polymorphism of the MTHFR gene affects the homocysteine levels in the serum by altering the functional activity of the MTHFR enzyme. The concomitant occurrence of NTDs with omphalocele was also associated with C677T mutation of MTHFR gene. In the present study, the molecular analysis report of the mother in Fetus 2 showed mutation of the MTHFR C677T gene. In the present study, the affected Fetuses 3 and 4 reported were monozygotic twins. According to a study by Padmanabhan, twinning is a significant factor for the development of NTDs, since more cases of NTDs are seen in families with twins. Monozygotic twins are more prone to congenital anomalies than dizygotic twins.
Prenatal counseling, antenatal care and perinatal folic acid supplementation, and fortification coupled with early screening are some of the effective preventive measures. Over the past three decades, a significant decline in NTD births has been recognized.
| Conclusion|| |
In this case series, the external features of craniorachischisis in four female fetuses (including monozygotic twins) are reported. One of the affected fetuses had associated omphalocele.
The authors sincerely thank those who donated their bodies to science so that anatomical research could be performed. Results from such research can potentially increase humankind's overall knowledge that can then improve patient care. Therefore, these donors and their families deserve our highest gratitude.
Authors also thank the Department of Obstetrics and Gynecology, for providing the fetuses for our study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]