Brain Tumor Res Treat.  2013 Apr;1(1):28-31. 10.14791/btrt.2013.1.1.28.

Inflamed Symptomatic Sellar Arachnoid Cyst: Case Report

• Park KH
• Gwak HS
• Hong EK
• Lee SH

• KMID: 2165219
• DOI: http://doi.org/10.14791/btrt.2013.1.1.28

Abstract

Sellar arachnoid cysts are rare; an infected arachnoid cyst is extremely rare as only one case has been reported to date in the literature. Here, we report a patient with an infected or inflamed sellar arachnoid cyst that was successfully treated with transsphenoidal surgery (TSA). A 53-year-old female with a history of chronic sinusitis developed a headache 5 months ago, and one month before admission polyuria, polydipsia, and abnormal vaginal bleeding occurred. The magnetic resonance imaging (MRI) showed a sellar cystic mass with a thickened pituitary stalk. Preoperative hormonal study revealed normal pituitary hormone levels except for a moderate elevation of prolactin. She was diagnosed with diabetes insipidus of the central nervous system origin based on a water-deprivation test. TSA was performed under an impression of symptomatic Rathke's cleft cyst according to the MRI findings. Intraoperative findings showed confirmation of turbid intracystic contents, but micro-organisms were unidentified on microbial culture. Pathology of the cyst wall revealed inflamed meningoepithelial lining cells compatible with an arachnoid cyst.

Keyword

Arachnoid cyst; Infection; Inflammation; Sellar; Symptomatic

MeSH Terms

Arachnoid Cysts
Arachnoid*
Central Nervous System
Diabetes Insipidus
Female
Headache
Humans
Inflammation
Magnetic Resonance Imaging
Middle Aged
Pathology
Pituitary Gland
Polydipsia
Polyuria
Prolactin
Sinusitis
Uterine Hemorrhage
Prolactin

Figure

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  Fig. 1 Preoperative MR images. Axial T1 non-enhanced (A) and gadolinium enhanced (B) images show a well-defined intrasellar cystic lesion, and the wall is faintly enhanced. FLAIR image suggested the content of cyst was not CSF but high proteinous material, which was compatible with Rathke's cleft cyst (C). Enhanced sagittal image showed that the cyst was attached to the thickened pituitary stalk and displaced the pituitary gland inferiorly (D). MR: magnetic resonance, CSF: cerebrospinal fluid, FLAIR: fluid attenuated inversion recovery.

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  Fig. 2 Photomicrograph of the cyst. The inner layer of the cyst wall shows a single layer of flattened meningothelial cells and the outer layer is composed of collagenous tissue, slightly thickened by mononuclear inflammatory cell infiltration and edema (hematoxilin and eosin; A: ×100, B: ×200). The immunohistochemical stains of the lining cells of the cyst are positive for epithelial membrane antigen (C) and negative for glial fibrillar acidic protein (D), which is consistent with an arachnoid cyst. There is no glial tissue in the outer layer of the cyst (×200).

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  Fig. 3 MRI taken 3 months postoperatively showing disappearance of previous sellar cyst and preserved pituitary gland and stalk. MRI: magnetic resonance imaging.

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