PMC4855788_01
Preoperative MRI and CT images showing a cystic sellar lesion. A: Coronal T1 weighted MRI image, B: T2 weighted MRI image, C: Coronal Dynamic contrast enhanced T1 weighted MRI image, D: Sagittal dynamic contrast enhanced MRI image; E and F Coronal and sagittal contrast enhanced CT images.
gr1.jpg
PMC4855788_01_gr1.jpg
fig0005
The normal pituitary and pituitary stalk demonstrated a typical enhancement pattern, and were displaced laterally to the right by the lesion (Fig. 1). A computed tomography (CT) scan dedicated to the sellar region, with and without contrast, confirmed a cystic lesion, hypodense with no contrast enhancement (Fig. 1).
Postoperative Day 1 coronal MRI images showing cyst excised and the normal hypophysis. A: T1 weighted, B: T2 weighted and C: Dynamic contrast enhanced studies.
gr2.jpg
PMC4855788_01_gr2.jpg
fig0010
Histopathology and immunohistochemistry. A: Flattened arachnoid cells lined on thin basement membrane (H&E, x59.7). B: Basement membrane rich in reticulin fibers in cyst wall (Gomori's reticulum stain, x113.2). C: Cyst wall overlined by flattened arachnoidal cells reacting with EMA (arrow) (Biotinylated streptavidin complement, EMA, x127.5) D: Anterior pituitary cell cluster in close neighbourhood of cyst wall (Biotinylated streptavidin complement, Synaptophysin, x61.0).
gr3.jpg
PMC4855788_01_gr3.jpg
fig0015
On pathologic examination, monolayered and flattened meningothelial cap cells were observed in the fibrous cyst wall (Fig. 3A). The subepithelial stroma was composed of a thin, non-vascular connective tissue rich in reticulin fibers (Fig. 3B). Immunohistochemically overlying cells revealed, EMA positivity (Fig. 3C), while GFAP, Ki-67, synaptophysin, S-100 were negative. The anterior hypophyseal cells were observed Pan-ck (5/6/8/18) and synaptophysin (Fig. 3D) positive.