*Lecturer (Researcher),Head of the Fetal Medicine unit , National Research Centre , Egypt , The senior fellow of Cairo fetal Medicine unit ,Egypt
**Head of the Cairo fetal medicine unit , Egypt
*** professor, Cairo fetal medicine unit ,Egypt
**** Assistant professor, Cairo university , Egypt
***** Fellow, Cairo fetal medicine unit ,Egypt


Case report 

A 31-year-old (G2P1) pregnant women was referred to our fetal medicine unit at 17 weeks gestation for routine second trimester ultrasound scan.

Our examination revealed a large frontal skull defect with anterior part of the brain (frontal horns of both hemispheres and meninges herniating through it). 3D and 4D ultrasonography were done and confirmed the previous findings and also demonstrated herniated anterior parts of the meninges with herniated frontal lobes and thalami.

The cerebellum and posterior fossa structures were in place , with mild ventriculomegaly (posterior horns of the lateral ventricles measuring 11 mm).

The diagnosis of fronto-ethmoidal encephalocele was established and the patient was counseled about the poor prognosis of this anomaly. After counseling and discussion, the patient decided to continue her pregnancy.

A new ultrasound evaluations were made at 26 weeks and at 34 weeks, and revealed increase in the degree of ventriculomegaly to moderate (lateral ventricles: 14 mm). A Cesarean section was made at 38 weeks and postnatal findings were confirmed.

Parents started pediatric neurosurgical consultation and corrective surgery was discussed to be planned when the girl reaches a suitable weight while a ventriculoperitoneal shunt was inserted to treat the ventriculomegaly.

Image 1: 2D image showing the lesion in the frontoethmoidal region.

 


Image 2: 2D image showing a transverse section in the skull demonstrating the skull defect.

 


Image 3: 2D image showing a transverse section in the skull demonstrating the skull defect in the frontoethmoidal region.

 


Image 4: 3D rendered image showing frontoethmoidal encephalomeningocele. 

Video 1: 2D video showing the skull defect with the encephalomeningocele.

Image 7: Postnatal image confirmed the prenatal diagnosis of frontoethmoidal encephalocele.

Introduction

Frontoethmoidal encephaloceles  are second only to occipital encephaloceles in terms of frequency, representing approximately 15% of all encephaloceles. They represent meninges or brain tissue herniating through cranial defect in the anterior cranial fossa and typically result in facial deformity. ¹Although the classification of encephaloceles is very variable, generally fronto ethmoidal encephaloceles are further divided into three subtypes on the basis of location of defect and path through facial structures into : naso-ethmoidal (most common) , naso-frontal and naso-orbial (least common). ^1,2,4

Epidemiology

The incidence of fronto-ethmoidal encephaloceles is between 0.8 and 4 per 10,000 births and there is no reported sex predominance. They are, however, more common in south-east Asian then Western countries ³.

Clinical presentation
Presentation depends on location and size of the defect and protrusion. If large the obvious facial deformity will be present with a mass of variable appearance (sessile or pedunculated; normal skin color or pigmentation, soft or firm, may have excessive hair/hypertrichosis) ². In addition to mass effect encephaloceles may also present with CSF leakage (rhinorrhea) or meningitis.

Treatment and prognosis
Surgical treatment of infant that survive the initial meningitis and shock may improve the short term outcome but few series describe the longer term outcome for the children as well as the ability to live independent life

References

1. David DJ. Cephaloceles: classification, pathology, and management-a review. J Craniofac Surg. 1994;4 (4): 192-202. Pubmed citation

2. Dhirawani RB, Gupta R, Pathak S et-al. Frontoethmoidal encephalocele: Case report and review on management. Ann Maxillofac Surg. 2014;4 (2): 195-7. doi:10.4103/2231-0746.147140 - Free text at pubmed - Pubmed citation

3. Bhattacharjee A, Chakraborty A, Purkaystha P. Frontoethmoidal encephalomeningocoele with colpocephaly: case report and clinical review. J Laryngol Otol. 2008;122 (03): 321-3. doi:10.1017/S0022215107000308 - Pubmed citation

4. Textbooks of Operative Neurosurgery ( 2 Vol.). B.I. Publications. (2005) ISBN:817225217X.