Heterotopic neuroglial tissue (HNT) was first described by Reid in 1852 [
13]. Composed of differentiated neuroectodermal tissue, these lesions represent developmental heterotopia of neuroglial tissue rather than true neoplasms [
3,
10]. Unlike meningoencephaloceles, brain heterotopias lack connection with the subarachnoid space [
14,
15]. Patients are usually seen initially in the newborn period with airway obstruction, feeding difficulty, or a neck mass. The most common location of HNT is the nasal cavity, where it is traditionally but erroneously termed 'nasal glioma'. Less commonly, brain heterotopias have been reported in the scalp, tongue, pharynx, palate, orbit, and neck [
3]. The majority of patients with HNT are products of uncomplicated pregnancies. This anomaly seems to have a left side and female predominance in previously reported cases [
3‐
5], as in our case. Other associated developmental anomalies have been reported, such as cleft palate, Pierre-Robin syndrome, and congenital heart disease [
3‐
5]. The pathogenesis of heterotopic neuroglial tissue is unclear. Several mechanisms have been proposed. CT and MRI scans are complementary studies necessary in pre-operative planning to determine the extent and location of the mass and to exclude intra-cranial connection [
16]. Surgical excision is the treatment of choice, although the time it should be performed is controversial. Before surgery, it is difficult to differentiate the neuroglial heterotopia from lymphangioma, as in cases such as our patient. The only clue is a giant single locular (as in our case) rather than multiseptated cyst, which can be commonly seen in lymphangioma; however, heterotopic neuroglial tissue presenting as a giant single locular cyst has been reported on a few occasions. Another way to differentiate these two entities is laboratory study of the fluid.
The treatment for heterotopic brain tissue is complete surgical excision. Surgical intervention is necessary in patients with heterotopic parapharyngeal neuroglial tissue that causes airway distress, dysphagia, or failure to thrive. The timing of surgery is controversial. Proponents of delayed resection believe that resection might be safer in the older child, in whom vital neurovascular structures are more easily salvageable and blood volume is greater [
3‐
6]. Recurrence as a result of incomplete excision has been described [
5]. Although focal areas of immature cells have been reported [
17,
18], these masses lack invasive patterns and are not true neoplasms. Rigorous post-operative care includes attention to nutritional status and speech and swallowing therapy [
6].