Technical considerations to prevent postoperative endocrine dysfunction after the fenestration of suprasellar arachnoid cyst

Abstract

Objective: The endocrine dysfunction after the operation for suprasellar arachnoid cysts is not rare. The careful operation to prevent structures can prevent this complication, but it is not enough and effective to prevent it. Authors present technical surgical considerations to prevent this complication with a review of our suprasellar arachnoid cyst patients who had postoperative endocrine dysfunction.

Methods: From January 2002 to December 2009, eight patients who had suprasellar arachnoid cysts with visual impairment underwent surgery. The mean age was 57.1 years (range, 33-77). Preoperatively, their endocrine function was clinically normal, and laboratory hormonal levels were within normal ranges. Cyst fenestration was performed by craniotomy (n=6) or by a neuro-endoscopic procedure (n=2), and, simultaneously, along with a cyst wall biopsy.

Results: The surgery was uneventful in all eight patients, and there were no neurological morbidities. However, in four patients, endocrine dysfunction occurred postoperatively. We compared these four patients (group A) to the other 4 patients without endocrine dysfunction (group B) with intraoperative findings and with the histopathological findings of the cyst wall biopsy. The group A patients had more abundant vasculature on the cystic wall than the group B patients according to both the intraoperative findings and the histopathological findings.

Conclusion: When performing a surgical cyst wall fenestration, surgeons should try to minimize the destruction of the cystic wall vasculature and not to make the fenestration at a site that contains many vascular striae.

Keywords: Cyst fenestration; Endocrine dysfunction; Suprasellar arachnoid cyst.

Fig. 1

Preoperative radiological images illustrating the cystic lesions of one patient (Case 6). The patient is a 61-year-old female with decreased visual acuity and abnormal visual field. A : On computed tomography (CT), a cystic lesion on suprasellar area is seen. B (sagittal) and C (coronal) on T1WI with enhancement, D (axial) on T2WI : The cystic lesion is detected on brain MRI with enhancement. The suprasellar cystic lesion with enhanced wall compressed optic chiasm. T1WI : T1-weighted image, T2WI : T2-weighted image, MRI : magnetic resonance imaging.

Fig. 2

Photomicrographs illustrating the histopathological findings of patients. A : The cystic wall component is shown with other tissues, which may be pituitary-related structures, suspectively. B : Only the cystic wall component is shown without other tissue which may be pituitary related structures. The figure A is from patient with endocrine dysfunction (group A), and the figure B is from patient without postoperative endocrine dysfunction (group B).

Fig. 3

Intraoperative pictures illustrating cysts before fenestration of 2 patients (Two pictures were from each groups). The large arrow on each picture indicates each cystic wall. A : Illustrates a cystic wall with some vasculatures (group A). B : Illustrates a clean cystic wall with no or scanty vasculature (group B).

Fig. 4

Intraoperative pictures illustrating cysts after the fenestration (the views for cyst are the same as those in Fig. 3). A : The pituitary structure is not observed and the vasculature on the cystic wall was injured (group A). B : Pituitary structures including the stalk were observed (the large arrow indicates a pituitary stalk) (group B).

Fig. 5

Postoperative radiological images were conducted on the same patient as in Fig. 1. The MRI scan shows decreased size of the cyst. A : Sagittal image on T1WI. B : Coronal image on T2WI. C : Axial image on T2WI). MRI : magnetic resonance imaging, T1WI : T1-weighted image, T2WI : T2-weighted image.