Symptomatic glial cysts of the pineal gland

Abstract

Small asymptomatic cysts of the pineal gland represent a common incidental finding in adults undergoing computerized tomography or magnetic resonance (MR) imaging or at postmortem examination. In contrast, large symptomatic pineal cysts are rare, being limited to individual case reports or small series. The authors have reviewed 24 cases of large pineal cysts. The mean patient age at presentation was 28.7 years (range 15 to 46 years); 18 were female and six male. Presenting features in 20 symptomatic cases included: headache in 19; nausea and/or vomiting in seven; papilledema in five; visual disturbances in five (diplopia in three, "blurred vision" in two, and unilateral partial oculomotor nerve palsy in one); Parinaud's syndrome in two; hemiparesis in one; hemisensory aberration in one; and seizures in one. Four lesions were discovered incidentally. Magnetic resonance imaging typically demonstrated a 0.8- to 3.0-cm diameter mass (mean 1.7 cm) with homogeneous decreased signal intensity on T1-weighted images, increased signal intensity on T2-weighted images, and a distinct margin. Hydrocephalus was present in eight cases. The cysts were surgically excised via an infratentorial/supracerebellar approach (23 cases) or stereotactically biopsied (one case). Histological examination revealed a cyst wall 0.5 to 2.0 mm thick comprised of three layers: an outer fibrous layer, a middle layer of pineal parenchymal cells with variable calcification, and an inner layer of hypocellular glial tissue often exhibiting Rosenthal fibers and/or granular bodies. Evidence of prior hemorrhage, mild astrocytic degenerative atypia, and disorganization of pineal parenchyma were often present. Postoperative follow-up review in all 24 cases (range 3 months to 10 years) revealed no complications in 21, mild ocular movement deficit in one, gradually resolving Parinaud's syndrome in one, and radiographic evidence of a postoperative venous infarct of the superior cerebellum with ataxia of 1 week's duration in one. Of the patients referred for study, the cysts were most often initially misdiagnosed as a pineocytoma in eight and a pilocytic astrocytoma in three. Only two patients were correctly diagnosed as having pineal cysts. This stresses the importance of recognizing the histopathological spectrum of pineal cysts, as well as correlation with radiographic findings, if a correct diagnosis is to be attained.

Pineal cyst resection in the absence of ventriculomegaly or Parinaud's syndrome: clinical outcomes and implications for patient selection

“…5 Over the subsequent years, sporadic reports of large symptomatic pineal cysts causing headache, Parinaud's syndrome, long tract signs, and pineal apoplexy appeared in the literature. 10,11,17,19,20,25 Although rare cases of pineal cysts continued to be reported, in nearly all cases the determination of "symptomatic" relied on signs of ventriculomegaly or Parinaud's syndrome. Klein and Rubinstein reported that among a surgical series of 7 symptomatic pineal cysts ranging in size from 1.0 to 4.5 cm, 5 patients demonstrated improvement following surgery.…”

“…[1][2][3]6,8,22 In rare cases, large cysts may obstruct the cerebral aqueduct, causing ventriculomegaly or compress the tectum, causing Parinaud's syndrome. 7,10,11,15,18,26 In our practice we have treated 3 patients who presented with hydrocephalus caused by compression of the aqueduct by a pineal cyst. While these findings are well-accepted indications for surgery, the majority of patients with pineal cysts do not present with these signs, and indications for intervention in these patients is unclear.…”

A Hemorrhagic Pineal Cyst with a Bacterial Meningitis-like Manifestation and Benign Outcome

“…Although the majority of these cysts are benign and are usually asymptomatic, some are occasionally associated with headaches, hydrocephalus, extraocular movement abnormalities and Parinaud's syndrome (2,3). The hemorrhage of a pineal cyst, which is sometimes referred to as pineal apoplexy, is considered to be rare and is often associated with severe symptoms (4)(5)(6).…”

Incidental Findings on Brain and Spine Imaging in Children

“…123 Rarely, large pineal cysts have also been associated with gaze palsy and Parinaud syndrome. 106,108,118,122,124,125 Although large cysts may be symptomatic, this occurrence is rare. The vast majority of even large cysts may be expected to present incidentally and remain asymptomatic.…”