Rare case of anterior fontanelle epidermoid/dermoid.

Anterior fontanelle cysts are rare in occurrence in the area of anterior fontanelle. Most of them are dermoid cysts. Epidermoid cysts are even rarer to be seen. Authors are reporting a rare case of epidermoid cyst located in anterior fontanelle along with two cases of dermoid in this area. Magnetic resonance imaging revealed that a cystic swelling was present in the anterior fontanelle area. Few cases have been reported in the literature. Present case of epidermoid is analysed and available literature is reviewed.

Introduction

Anterior fontanelle inclusion cysts are rare in occurrence, and account for 0.1–0.2% of all skull tumors.[123] These inclusion cysts present in 1st year of life and gradually increase in size. Most common age of presentation is 3–6 months as a gradually increasing cystic swelling.[124567] Dermoid cysts (congenital dermoid inclusion cyst [CDIC]) are more commonly seen than epidermoid.[8] On reviewing the available literature only few cases have been reported of an epidermoid cyst in anterior fontanel area.[8] Authors are reporting a case of epidermoid cyst (congenital epidermoid inclusion cyst [CEDIC]) and available literature about epidermoid and dermoid cyst is being reviewed.

Usual presentation of CEDIC is same as CDIC as a swelling on the top of the head which may be pulsatile and which may become prominent on crying.[13] Usually swelling show transmitted pulsations. Other swellings in this area which are rarely seen are cephalhaematoma, encephalocoele, lymphangioma, haemangioma, lipoma or sebaceous cyst.[7] Till June 2003 only 226 cases were reported of dermoid cyst, however, only two cases were reported of epidermoid cyst world over up to 2006 in world literature.[9] Two more cases were reported in 2009.[7] These two subgroups were further analyzed and literature was searched and cases were further added in the dermoid group and new cases were searched in epidermoid group.[910]

Case Reports

In 25 years of neurosurgical practice in a teaching institution three cases of swelling in the anterior fontanelle area were encountered by the neurosurgeon.

Case 1

This 6-month-old male child presented with a swelling in the area of anterior fontanelle since birth [Figure 1]. Swelling was fluctuant in nature and trans illumination test was not positive. This was becoming more prominent on crying. Transmitted pulsations were present. This was the first child of the family. There was no history of any congenital abnormalities in the family. The child was evaluated for any other focal or systemic abnormality including cardiovascular system. Patient was evaluated by magnetic resonance imaging (MRI). MRI showed a well-defined cystic swelling over the top of head in the anterior fontanelle which was not apparently communicating with the cranial cavity [Figure 2]. Venography and evaluation of sinuses showed that there was no apparent communication of swelling with the cranial cavity or the superior saggital sinus. The space between the superior saggital sinus and the cyst wall was very little and MRI in coronal showed that there was possible communication of cyst with brain parenchyma.

Figure 1

Preoperative photo of patient

Figure 2

Magnetic resounace imaging brain showing demarcation of cyst from brain

Case 2

Four months old male child presented with swelling in the anterior fontanelle area present since birth. This was gradually increasing in size and was having transmitted pulsations. Patient was evaluated by MRI which showed that a cystic mass was present in the area of anterior fontanelle and it was not having any communication with superior saggital sinus or brain. No family history of any congenital abnormalities was available.

Case 3

Six months old child presented with a soft cystic swelling over the head in the area of anterior fontanelle which again was becoming tense on crying and was nontransilluminant on transillumination. Swelling was gradually increasing in size. Patient was evaluated by a computed tomography (CT) scan test and then referred to this centre. CT scan showed that there was a cystic swelling which was apparently not communicating with the cranial cavity or the superior saggital sinus but the relation was not clear and MRI was then done which showed the clear line of demarcation between cyst and the sinus.

All the three cases were operated in similar method. The child was placed in supine position and swelling was propped up as to make the swelling in the most prominent position and transverse incision was made. Cyst was gradually dissected out. Dissection in the base was carried in the last. In all three cases there was a very thin dura and blue superior saggital sinus could be seen [Figure 3]. Postoperative period was uneventful in all the three cases. Histopathology revealed cyst to be epidermoid cyst in first case and dermoid in case number two and three.

Figure 3

Intraoperative photograph

Discussion

Swellings in the anterior fontanelle area are rare and in a busy neurosurgeon's life two to three such cases are encountered [Table 1]. It is mandatory to investigate the swelling by MRI or at least by a good quality CT scan. Possibility of vascular malformation, meningo-encephalocoele or a lymphangioma or a sebaceous cyst should be always kept in mind. It is also must to evaluate for relationship of swelling with superior saggital sinus and communication with cranial cavity should be kept in mind. Adequate arrangements for repair of superior saggital sinus and replacement of blood should be made before surgery. Generous coronal incision should be given and dissection from periphery to mid line should be carried out and attachment on the superior saggital sinus should be dissected in the last. If there is tear in the superior saggital sinus or in the dura it should be repaired by muscle patch or any other patch as needed. Postoperative care is done in usual fashion. There is no role of starting antiepileptic drugs prior to or after surgery.

Table 1

Reveiw of literature

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.