Heterotopic Brain in the Pterygopalatine Fossa

Abstract

Summary: Heterotopic brain outside the cranial vault is uncommon. lt occurs most frequently in the nasal region, although rests elsewhere in the aerodigestive tract have been reported. We describe a case of heterotopic brain in the pterygopalatine fossa.

Heterotopic Neuroglial Tissue Causing Airway Obstruction in the Newborn

“…Magnetic resonance characteristics of heterotopic neuroglial tissue resemble normal brain tissue in all pulse sequences. 1 Cystic elements might be present and represent cerebrospinal fluid-like fluid-filled spaces. A CT cisternogram might give additional information regarding connection with the subarachnoid space.…”

Glial Heterotopia in ENT—Two Case Reports and Review of Literature

“…They are composed of nests of neural tissue without mitosis, embedded within varying amounts of fibrovascular stroma [17]. Heterotopias of the tongue described earlier have been found to include ependymal lined structures, choroid plexus and pigmented cells of retinal differentiation apart from the dominant component of astrocytes, neurons and oligodendrocytes [17,19]. Grossly the tissue is relatively avascular, solid, firm, poorly encapsulated and adherent to the surrounding soft tissues [20].…”

“…These include an encephalocele that loses its intracranial connection resulting in heterotopic neuroglial tissue [17,18]. Another mechanism is displacement of neuroectodermal cells during early embryogenesis, which later develops into mature glial tissue [18,19]. Glial cells migrating from the olfactory bulb is yet another mechanism [17].…”

Glial heterotopia in head and neck, single center experience of 5 cases

“…4 One commonly accepted theory is that heterotopic neural tissue is a variant of encephalocele in which the central nervous system connection has been absorbed or become vestigial. 1,5 These lesions may be classified based on their location and possible pathogenic mechanisms as follows: a) intraparenchymal CNS lesions; b) dural and lepto-meningeal lesions; c) intracranial extra-cerebral lesions; d) distal lesions thought to result from a previous pregnancy; e) midline "nasal gliomas," thought to originate as encephaloceles; and f) non-midline lesions of the head and neck. 1 Nasal Glial Heterotopias (NGH) are congenital tumours of the midline frontonasal space arising from a normal neuroectodermal tissue entrapped during the closure of the anterior neuropore.…”