Suprasellar arachnoid cyst with temporal extension or temporal cyst with suprasellar extension?

Abstract

A 4-year-old female child presented to an emergency hospital with headache and episodes of seizures. Computed tomography and magnetic resonance imaging of the skull (Figs. 1a, b and c) were performed; they showed large suprasellar cystic lesions with right temporal extension and mild hydrocephalus. Subsequently, an endoscopic ventriculocystocysternotomy was performed (Figs. 1d, e, and f), which showed good results. Suprasellar arachnoid cysts account for 9%–21% of the pediatric arachnoid cysts [1,2]. According to the morphology and characteristics, there are three types of suprasellar arachnoid cysts, as follows: 1. Diencephalic leaflet dilatation of the Liliequist membrane with the formation of purely suprasellar cysts, which presents with hydrocephalus; 2. The defect of the mesencephalic leaflet of the Liliequist membrane with dilatation of the interpeduncular cistern, which presents without hydrocephalus; 3. Asymmetrical form that extends to other subarachnoid spaces, which presents with macrocrania and mild or no hydrocephalus [1], similar to the present case. The expansion could be due to an osmotic gradient, a slit valve mechanism, tissue debris transudation from the choroid plexus, or ectopic glial cells [3]. The first treatment option for suprasellar arachnoid cysts should be endoscopic ventriculocystocysternotomy; ventriculoperitoneal shunt may be considered the second treatment option if endoscopic ventriculocystocysternotomy fails [2]. Figure Caption Magnetic resonance imaging of the brain: (a) T1 axial and (b) T2 axial showing a large suprasellar (black arrows) cyst with expansion to the right temporal pole, having a mass effect and mild ventricular dilatation(white arrows) without ependymal transudation; (c) Sagittal FIESTA-T2 with compressive effect on the brain stem(white arrow) and basilar artery(black arrow) displacement; Endoscopic view: (d) ventriculocystotomy; (e) the third ventricular floor with pituitary stalk(black arrow) and gland(white arrow), dorsum of the sella turcica(black curved arrow), posterior communicating artery(black arrowhead), and oculomotor nerve(white arrowhead); (f) cyststocisternotomy was conducted with visualization of the basilar artery((black arrow) and dorsum of the saddle.