Benign symptomatic lesions of the pineal gland. Report of seven cases treated surgically

Pineal cysts without hydrocephalus: microsurgical resection via an infratentorial-supracerebellar approach-surgical strategies, complications, and their avoidance

Indications for surgery of pineal cysts without ventriculomegaly are still under debate. In view of the limited data for pineal cyst resection in the absence of hydrocephalus, and the potential risk of this approach, we have analyzed our patient cohort focusing on strategies to avoid complications according to our experience in a series of 73 pineal cyst patients. From 2003 to 2015, we reviewed our database retrospectively for all patients operated on a pineal cyst. Furthermore, we prospectively collected patients from 2016 to 2020. In summary, 73 patients with a pineal cyst were treated surgically between 2003 and 2020. All patients were operated on via a microscopic supracerebellar-infratentorial (SCIT) approach. The mean follow-up period was 26.6 months (range: 6-139 months). Seventy-three patients underwent surgery for a pineal cyst. An absence of enlarged ventricles was documented in 62 patients (51 female, 11 male, mean age 28.1 (range 4-59) years). Main presenting symptoms included headache, visual disturbances, dizziness/vertigo, nausea/emesis, and sleep disturbances. Complete cyst resection was achieved in 59/62 patients. Fifty-five of 62 (89%) patients improved after surgery with good or even excellent results according to the Chicago Chiari Outcome Scale, with complete or partial resolution of the leading symptoms. Pineal cysts resection might be an indication in certain patients for surgery even in the absence of ventriculomegaly. The high percentage of postoperative resolution of quality-of-life impairing symptoms in our series seems to justify surgery. Preoperatively, other causes of the leading symptoms have to be excluded.

Spontaneous Resolution of Dorsal Midbrain Syndrome Caused by a Pineal Cyst

BACKGROUND

Pineal lesions are common causes of dorsal midbrain syndrome and typically require surgical intervention in symptomatic patients. We describe a unique case of spontaneous resolution of dorsal midbrain syndrome resulting from a pineal gland cyst.

CASE DESCRIPTION

A 23-year-old woman developed a supranuclear upgaze palsy, convergence-retraction nystagmus, and light-near dissociation from a pineal gland cyst (1.0 × 1.3 × 1.2 cm) with mild mass effect on the posterior surface of the tectum. Seven days after symptom onset, she had complete, spontaneous resolution of her symptoms, and examination returned to normal. Repeat magnetic resonance imaging demonstrated an unchanged pineal cyst with new T2/fluid attenuated inversion recovery hyperintensity along the mesial surface of the left thalamus.

CONCLUSIONS

Dorsal midbrain syndrome resulting from a pineal cyst may spontaneously improve even without a significant change in lesion size. This suggests that observation may be an appropriate initial management strategy.

Systematic review of pineal cysts surgery in pediatric patients

INTRODUCTION

We present a consecutive case series and a systematic review of surgically treated pediatric PCs. We hypothesized that the symptomatic PC is a progressive disease with hydrocephalus at its last stage. We also propose that PC microsurgery is associated with better postoperative outcomes compared to other treatments.

METHODS

The systematic review was conducted in PubMed and Scopus. No clinical study on pediatric PC patients was available. We performed a comprehensive evaluation of the available individual patient data of 43 (22 case reports and 21 observational series) articles.

RESULTS

The review included 109 patients (72% females). Ten-year-old or younger patients harbored smaller PC sizes compared to older patients (p < 0.01). The pediatric PCs operated on appeared to represent a progressive disease, which started with unspecific symptoms with a mean cyst diameter of 14.5 mm, and progressed to visual impairment with a mean cyst diameter of 17.8 mm, and hydrocephalus with a mean cyst diameter of 23.5 mm in the final stages of disease (p < 0.001). Additionally, 96% of patients saw an improvement in their symptoms or became asymptomatic after surgery. PC microsurgery linked with superior gross total resection compared to endoscopic and stereotactic procedures (p < 0.001).

CONCLUSIONS

Surgically treated pediatric PCs appear to behave as a progressive disease, which starts with cyst diameters of approximately 15 mm and develops with acute or progressive hydrocephalus at the final stage. PC microneurosurgery appears to be associated with a more complete surgical resection compared to other procedures.

[Pineal cyst]

A pineal cyst (PC) is a benign neoplasm in the pineal region, or more precisely in the pineal body. Most cysts are incidental findings and are not associated with symptoms typical of patients seeking medical advice. Symptomatic cysts are discovered less often and, depending on the clinical picture, require different treatment approaches.

MATERIAL AND METHODS

We analyzed the literature data about the clinical picture, diagnosis, and treatment of PCs for more than a century (1914-2016).

CONCLUSION

To date, there is no single approach for managing PC patients. The indications for surgical treatment of symptomatic PCs are still not fully defined. It remains unclear which PC cases should be followed-up, and how often control examinations should be performed. More research of PCs is needed to develop new approaches to treatment of PC patients.

Incidental Pineal Cysts: Is Surveillance Necessary?

OBJECTIVE

The natural history of incidental pineal cysts is poorly understood. Neurosurgeons and neuroradiologists are more frequently faced with this disease in the advent of higher-resolution magnetic resonance imaging (MRI) scanning. We aim to suggest a suitable surveillance strategy for these patients.

METHODS

All patients who had MRI of the brain between June 2007 and January 2014 (n = 42,099) at The Walton Centre for Neurology and Neurosurgery were included. Radiologic reports containing the terms "pineal" and "cyst" were reviewed to identify patients.

RESULTS

A total of 281 patients were identified with pineal cysts. The principal indication for head MRI was headache (50.2%), although no symptoms were deemed attributable to pineal disease. A total of 178 patients (63.3%) were female, and the age at diagnosis ranged from 16 to 84 years. The median size of pineal cyst at diagnosis was 10 mm. A total of 181 patients had subsequent follow-up at a median time of 6 months (range, 1-68). Eleven pineal cysts (6%) changed size during the follow-up period. Four patients had a reduction in cyst size; the median change was 2.5 mm. A further 7 pineal cysts increased in cyst size; the median change was 2 mm. No patients developed complications.

CONCLUSIONS

Incidental pineal cysts typically show a benign course. In the adult population, they do not require long-term neurosurgical follow-up, because pineal cysts tend to remain a stable size. In asymptomatic patients, we recommend a single follow-up MRI scan at 12 months to confirm diagnosis. The patient should then be discharged if the cyst remains stable.

Magnetic resonance imaging biomarkers indicate a central venous hypertension syndrome in patients with symptomatic pineal cysts. J Neurol Sci. 2016;363:207-216. [PMID: 27000252 DOI: 10.1016/j.jns.2016.02.038]

BACKGROUND

While most pineal cysts (PCs) are asymptomatic, some PCs are accompanied with symptoms of variable severity. We suggested that symptom severity in symptomatic patients with non-hydrocephalic PCs relates to venous compression causing central venous hypertension. This study explored whether possible magnetic resonance imaging (MRI) biomarkers of central venous hypertension could differentiate the severity of symptoms in individuals with non-hydrocephalic PCs.

METHODS

The study included all individuals with PCs and MRI available for analysis followed conservatively within the department from 2003 to 2014. Severity of symptoms at follow-up were assessed from a questionnaire. Suggested MRI biomarkers indicative of central venous hypertension were explored, in addition to MRI measures of cyst size, aqueduct stenosis, and tectal compression.

RESULTS

The study included 66 patients. As compared to the 27/66 patients (41%) with "None-Moderate" symptoms at follow-up, the 39/66 patients (59%) with "Much-Severe" symptoms presented with significantly altered indices of central venous hypertension (tectum-splenium-cyst ratio and indices of thalamic and periventricular edema). PC grading based on MRI biomarkers of central venous hypertension differentiated the severity of symptoms.

CONCLUSION

The results indicate an association between severity of symptoms and MRI biomarkers of central venous hypertension in symptomatic individuals with non-hydrocephalic PCs.

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

OBJECT

Surgical indications for patients with pineal cysts are controversial. While the majority of patients harboring a pineal cyst require no treatment, surgery is a well-accepted option for a subset of those patients with secondary hydrocephalus or Parinaud's syndrome. The majority of pineal cysts are identified incidentally during workup for other potential conditions, which may or may not be related to the presence of the cyst. In the absence of clear obstruction of CSF pathways, the treatment of presumed symptomatic pineal cysts is debatable. To clarify the role of surgery in these borderline cases, the authors reviewed their experience with resection of pineal cysts in the absence of ventriculomegaly or Parinaud's syndrome.

METHODS

The authors retrospectively reviewed medical records and imaging of all patients surgically treated between 2001 and 2014 with a pineal cyst in the absence of ventriculomegaly and Parinaud's syndrome. The presenting symptoms, preoperative cyst size, preoperative radiographic aqueductal compression, extent of resection, and radiographic and clinical follow-up were documented.

RESULTS

Eighteen patients (14 female and 4 male; mean age 24 years, range 4–47 years) underwent cyst resection in the absence of ventriculomegaly or Parinaud's syndrome. Presenting symptoms included headache (17 patients), visual disturbances (10 patients), gait instability (5 patients), dizziness (5 patients), episodic loss of consciousness (2 patients), and hypersomnolence (1 patient). The mean preoperative cyst diameter was 1.5 cm (range 0.9–2.2 cm). All patients had a complete resection. At a mean clinical follow-up of 19.1 months (range postoperative to 71 months), 17 (94%) patients had resolution or improvement of their presenting symptoms.

CONCLUSIONS

The authors' results suggest that ventriculomegaly and Parinaud's syndrome are not absolute requisites for a pineal cyst to be symptomatic. Analogous to colloid cysts of the third ventricle, intermittent occlusion of cerebrospinal fluid pathways may cause small pineal cysts to become intermittently symptomatic. A select cohort of patients with pineal cysts may benefit from surgery despite a lack of hydrocephalus or other obvious compressive pathology.

Update on the management of pineal cysts: Case series and a review of the literature. Neurochirurgie. 2015;61:201-207. [PMID: 24907165 DOI: 10.1016/j.neuchi.2013.08.010]

OBJECTIVE

The natural history of pineal cysts still remains unclear. Incidental pineal cysts have become more common which raises the question of their management. Symptomatic pineal cysts may require a surgical solution but therapeutic indications have not yet been clearly established.

METHOD

From 1986 to 2012, 26 patients with pineal cysts were identified. Their medical records were retrospectively assessed focusing on the initial symptoms, imaging characteristics of the cyst, management strategy, operative technique and their complications, as well as the latest follow-up. A systematic review of the literature is also presented.

RESULTS

Twenty-six patients with pineal cysts were identified. The mean age was 23.5 years ranging from 7 to 49 years. Symptoms included intracranial hypertension with obstructive hydrocephalus in 18 cases and oculomotor anomalies in 12 cases. Two adult cases presented with non-specific headaches and did not require surgery. Twenty patients were operated via a suboccipital transtentorial approach with total removal of the cyst in 70% of the cases, while the remaining 4 cases were treated with an intraventricular endoscopic marsupialization associating a third ventriculostomy. Four patients required a preoperative ventriculo-peritoneal shunt due to life-threatening obstructive hydrocephalus. Overall, peri-operative mortality was nil. In the two non-operated patients, the cyst remained stable and no recurrences were observed in all operated patients with a mean follow-up of 144 months.

CONCLUSION

In the majority of incidental pineal cysts, a clinical and imaging follow-up is sufficient but occasionally not required especially in adults as very rare cases of increase in size have been reported.

Pineal cysts in children: case-based update

PURPOSE

Pineal cysts (PC) are found in children as often asymptomatic and without change in their size over the time. However, there are some debatable issues about their evolution and management in the pediatric population. The aim of the present paper is to update the information regarding pathogenesis, clinical presentation, and management of these lesions.

METHODS

All the pertinent literature was reviewed, and a meta-analysis of operated on cases was carried out. An illustrative case regarding the clinical evolution of a 13-year-old girl is also presented.

RESULTS AND CONCLUSIONS

PC are often asymptomatic and do not evolve over the time. However, since there is a certain risk of clinical and/or radiological progression, or even sudden and severe clinical onset (apoplexy), both a clinical and radiological follow-up is recommended in the pediatric age. The surgical excision is usually limited to symptomatic patients or to cases with clear radiological evolution.

Prevalence and natural history of pineal cysts in adults

OBJECT

We reviewed our experience with pineal cysts to define the natural history and clinical relevance of this common intracranial finding.

METHODS

The study population consisted of 48,417 consecutive patients who underwent brain MR imaging at a single institution over a 12-year interval and who were over 18 years of age at the time of imaging. Patient characteristics, including demographic data and other intracranial diagnoses, were collected from cases involving patients with a pineal cyst. We then identified all patients with pineal cysts who had been clinically evaluated at our institution and who had at least 6 months of clinical and imaging follow-up. All inclusion criteria for the natural history analysis were met in 151 patients.

RESULTS

Pineal cysts measuring 5 mm or larger in greatest dimension were found in 478 patients (1.0%). Of these, 162 patients were male and 316 were female. On follow-up MR imaging of 151 patients with pineal cyst at a mean interval of 3.4 years from the initial study, 124 pineal cysts remained stable, 4 increased in size, and 23 decreased in size. Cysts that were larger at the time of initial diagnosis were more likely to decrease in size over the follow-up interval (p = 0.004). Patient sex, patient age at diagnosis, and the presence of septations within the cyst were not significantly associated with cyst change on follow-up.

CONCLUSIONS

Follow-up imaging and neurosurgical evaluation are not mandatory for adults with asymptomatic pineal cysts.

Histopathology of tumors of the pineal region

Pineal region tumors are heterogeneous lesions and include mainly pineal parenchymal tumors (PPTs), papillary tumors of the pineal region (PTPRs) and germ cell tumors (GCTs). This article describes the cystic pineal gland compared with normal tissue and histopathological features of the most frequent pineal region tumors. PPTs are subdivided into pineocytoma (grade I), pineoblastoma (grade IV) and tumors with intermediate differentiation (PPTIDs; grades II-III). A grading system based on the number of mitoses and neurofilament protein expression distinguishes low- from high-grade PPTID. PTPR is a new tumoral entity thought to originate from the subcommissural organ. GCTs include germinoma, embryonal carcinoma, teratoma, yolk sac tumor and choriocarcinoma and are often of mixed histologic composition. New histogenetic data for GCTs are presented.

The natural history of pineal cysts in children and young adults

OBJECT

The authors reviewed their experience with pediatric pineal cysts to define the natural history and clinical relevance of this common intracranial finding.

METHODS

The authors identified all patients with pineal cysts who had been clinically evaluated at their institution over an 11.5-year interval and were < 25 years of age at the time of diagnosis. All inclusion criteria were met in 106 patients, and included repeated MR imaging as well as repeated clinical evaluation over at least a 6-month interval.

RESULTS

The mean age at diagnosis was 11.7 +/- 7.2 years. Forty-two patients were male and 64 were female. On follow-up MR imaging evaluation at a mean interval of 3.0 years from the initial study, 98 pineal cysts had no increase in size and no change in imaging appearance. Six pineal cysts increased in size and 2 others had a change in imaging characteristics without associated growth. Younger age was associated with cyst change or growth on follow-up imaging (p = 0.02). The mean age of patients with cysts that changed or grew was 5.5 years, and the mean age of patients with stable pineal cysts was 12.2 years. Initial cyst size and appearance on MR imaging were not significant predictors of growth or change in imaging appearance at follow-up. Similarly, the patient's sex was not a significant predictor of growth or change in imaging characteristics.

CONCLUSIONS

Follow-up imaging and neurosurgical evaluation may be considered optional in older children with pineal cysts.

[Pineal cyst: usefulness of endoscopic treatment]

Glial cysts of the pineal gland are usually benign and asymptomatic. They develop from the pineal parenchyma and contain liquid. The diagnosis is made by magnetic resonance imaging. In contrast large cysts can be symptomatic due to compression of the aqueduct of Sylvius, compression of the midbrain tectum or mass effect in the posterior fossa. We report the case of a symptomatic cyst treated by an endoscopic procedure.

Traitement endoscopique d’un volumineux kyste bénin symptomatique de la région pinéale responsable d’une hydrocéphalie obstructive

Asymptomatic non neoplastic cysts of the pineal region are common incidental findings in adults. On the contrary, voluminous and symptomatic cysts of the pineal region are rare and their management are not well defined. We present the case of a 32-year-old woman suffering who suffered from mild intracranial hypertension, gait disturbance and vertigo for one year. The neuroradiological workup showed a voluminous cyst of the pineal region responsible for an obstructive hydrocephalus. An endoscopic etiological treatment was decided. The operation consisted in a marsupialization of the cyst in the third ventricle with a stereotactic guidance system. A frozen section of the cyst wall failed to show tumoral cells. Immediate postoperative course was uneventful. Intracranial hypertension symptoms resolved in 24 hours. Clinical examination and neuropsychological testing were normal at two years postoperatively. The two years follow-up cerebral MRI demonstrated a remnant cystic cavity without mass effect and the patency of the aqueduct of Sylvius. Endoscopic treatment of symptomatic pineal cysts constitutes an interesting therapeutic alternative in the management of this pathology.

Neuroendoscopic surgery of intracranial cysts in adults

OBJECTS

The purpose of this study was to describe the indications, surgical techniques and postoperative outcome of neuroendoscopic interventions in a heterogeneous group of intracranial cystic pathologies.

PATIENTS AND METHODS

Between 1992 and 2003, 127 patients with symptomatic intracranial cysts and cystic tumours underwent neuroendoscopic treatment in our department. In 22 patients indication for surgery was colloid cysts, in 9 patients pineal cysts and in 3 patients cavum vergae cysts. Twelve arachnoid cysts, 10 cystic craniopharyngiomas, 2 Rathke's cleft cysts and 69 malignant cystic tumours were operated on. The patients' mean age was 45 years and their clinical presentations varied from typical signs of increased intracranial pressure to focal neurological deficits.

RESULTS

One hundred and twenty-seven patients with intracerebral cystic space-occupying lesions were operated on using stereotactic frameless or frame-based endoscopic techniques. There was no operative mortality. The operative morbidity was 3.1% including 1 memory deficit due to fornix injury, 1 hemiparesis due to postoperative haematoma after lesion biopsy, 1 aseptic meningitis and 1 subdural fluid collection.

CONCLUSIONS

Endoscopic interventions enable neurosurgeons to manage intracranial cystic lesions. Via the same approach, the obstructed CSF pathways may be restored and consequently the increased intracranial pressure diminishes. With the aid of stereotactic guidance or a neuronavigation system, access to the lesion can be gained rapidly and with high accuracy.

Intraventricular congenital lesions and colloid cysts

Intraventricular congenital lesions and colloid cysts comprise a rather large spectrum of different pathologic conditions. In most cases, treatment in not warranted unless there is progressive ventricular obstruction with hydrocephalus or growth of the lesion itself, making tissue biopsy and histopathologic diagnosis necessary. Accordingly, a precise neuroradiologic evaluation is of the utmost importance, because most lesions, if not symptomatic, only require clinical and radiologic follow-up.

Pineal apoplexy: is it a facilitator for the development of pineal cysts?

BACKGROUND

The radiographic identification of pineal cysts has increased dramatically within the last two decades due to the advent of magnetic resonance imaging. Pineal cysts are often found incidentally with only a minority of these lesions ever becoming symptomatic and requiring treatment. Many theories attempting to explain the pathogenesis of these cysts exist.

METHODS

We describe a case of a 12-year-old girl who presents with a pineal hemorrhage of unknown etiology with associated hydrocephalus.

RESULTS

Her hydrocephalus was initially treated with an external ventricular drain followed by a third ventriculostomy. She had no evidence of elevated beta human chorionic gonadotropin or alpha-fetoprotein within the serum or cerebrospinal fluid. Follow-up imaging at seven weeks revealed resolution of her hemorrhage, however, there was development of a progressive cystic lesion within the pineal region. In order to make a definitive tissue diagnosis, a supracerebellar infratentorial surgical approach with complete resection was performed. During the resection, brownish fluid was aspirated from the cyst and the cyst wall was removed. The pathological diagnosis was a pineal cyst.

CONCLUSIONS

Although cases have been described of pineal apoplexy with an underlying cyst, this case describes the development of a progressive pineal cyst secondary to a hemorrhage. This case demonstrates that pineal hemorrhage may be a promotor for the development or progression of pineal cysts.

Neuroendoscopic management of pineal region tumours

The management of pineal tumours remains controversial. During 1994 we treated four consecutive adults (16-44 yrs) harbouring a pineal tumour with a neuroendoscopic procedure. All of them presented with hydrocephalus. Pre-operative workup included cranial computerized tomography (CT), craniospinal magnetic resonance imaging (MRI) and serum levels of biological tumour markers. The endoscopic procedure consisted of a third ventriculostomy followed by biopsy with a flexible, steerable neuroendoscope. Histological diagnosis was achieved in three patients who no longer required a shunt device. Recorded complications were: bleeding during ventriculostomy that prevented us from obtaining a good sample for biopsy, short-term memory loss that cleared over a two-week period, and transient increase of pre-operative hemiparesis. Complications and morbidity are emphasized so as to be avoided with further technical experience. Neuroendoscopy affords a minimally invasive way of reaching three objectives by one-step surgery in the management of pineal region lesions: 1) CSF sample for analysis of tumour markers. 2) Treatment of hydrocephalus by third ventriculostomy. 3) Several biopsy specimens can be obtained identifying tumours which will require further open surgery or adjuvant radiation and/or chemotherapy.

Stereotactic management of lesions of the pineal region

OBJECTIVE

The relevance of the computed tomography-guided stereotactic approach for the management of lesions of the pineal region is analyzed.

METHODS

In a retrospective analysis conducted between 1985 and 1993, the risk profile, the diagnostic accuracy, and the therapeutic relevance of the stereotactic approach in 106 patients was studied. Survival analysis was used to assess the reliability of the stereotactically obtained diagnosis in terms of follow-up observation.

RESULTS

A histological diagnosis was obtained in 103 of the 106 patients. In three patients, a conclusive diagnosis could not be established because of intraoperative complications. One lesion was misdiagnosed as a pineocytoma instead of a pineoblastoma. Two of the 106 patients died; 9 patients experienced perioperative morbidity. In 38 patients, the stereotactic approach was also useful for therapy. Cyst aspiration and/or internal drainage was performed in 18 patients with symptomatic cystic lesions, and radiosurgical treatment with use of interstitial 125iodine was performed in 16 patients with low-grade tumors and in 4 patients with solitary metastases. In 12 patients, the obtained tissue diagnosis was the basis for deferring additional therapy. In 43 patients with germ-cell tumors, pineoblastomas, or malignant gliomas, a stereotactic biopsy was the starting point for additional radiotherapy/chemotherapy. Open tumor resection played a minor role (five patients).

CONCLUSION

The stereotactic approach to the pineal region is a relatively safe procedure in experienced hands. The diagnosis obtained by computed tomography-guided stereotactic biopsy is a valid basis for treatment decisions. Long-term follow-up observation of the benign lesions is necessary for a definite confirmation of diagnostic accuracy.

Symptomatic glial cysts of the pineal gland

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.

Surgical management of symptomatic pineal cysts

The authors present a series of six patients with large symptomatic benign pineal cysts and review the 27 patients previously reported in the literature. Patients with symptomatic pineal cysts most often present with one of three syndromes: 1) paroxysmal headache with gaze paresis; 2) chronic headache, gaze paresis, papilledema, and hydrocephalus; or 3) pineal apoplexy with acute hydrocephalus. Surgical intervention with radical cyst removal is the treatment of choice for all symptomatic pineal cysts. Complete cyst removal is desirable; however, radical subtotal resection is appropriate if the cyst cannot be easily separated from the quadrigeminal plate. Ventricular shunting should be reserved for patients with persistent hydrocephalus after cyst resection.