The endoscopic intraventricular management of pineal cysts: a minimally invasive modus operandi

Defining Occult High-Risk Cysts of the Pineal Region: A Case Series

BACKGROUND

Absence of hydrocephalus on neuroimaging may impart a false sense of security for patients with pineal cysts. In this case series, we characterize a subset of patients with pineal cysts having an occult presentation. Unifying features of worsening paroxysmal headaches suggesting intermittent obstructive hydrocephalus and radiographic evidence of third ventricular invagination characterize these patients as high risk.

OBJECTIVE

To define features of occult, high-risk pineal cysts and outcomes of endoscopic cyst fenestration.

METHODS

Charts were retrospectively reviewed for patients with pineal cysts evaluated at our institution between 2018 and 2021 who underwent endoscopic cyst fenestration. To capture cysts presenting as occult, patients were excluded if hydrocephalus was noted at presentation. Relevant clinical history, imaging, operative data, and clinical outcomes were reviewed.

RESULTS

Of 50 pineal cyst patients, 4 satisfied inclusion criteria. All patients presented with worsening paroxysmal headaches. In addition, 75% (3/4) also experienced intermittent syncope. Patients exhibited no hydrocephalus (n = 3) or fluctuating ventricular size on longitudinal imaging (n = 1). In all cases, high-resolution sagittal 3-dimensional T2 magnetic resonance imaging demonstrated invagination of the cyst anteriorly into the posterior third ventricle. All patients underwent endoscopic cyst fenestration with complete symptom resolution (mean follow-up of 20.6 months; range 3.5-37.4 months).

CONCLUSION

The clinical history for occult, high-risk pineal cysts is notable for worsening paroxysmal headaches and episodic alterations of consciousness suggesting intermittent obstructive hydrocephalus. Because ventricular size can appear normal on standard imaging protocols, clinical suspicion should trigger workup with high-resolution magnetic resonance imaging designed to detect these cysts. Endoscopic cyst fenestration is a safe and efficacious management strategy.

Diagnosis and Management of Pineal Germinoma: From Eye to Brain

Pineal germinomas can be very complex in terms of presentation, diagnosis, and management. This review attempts to simplify this complexity in an organized manner, addressing the anatomic relationships that provide the basis for the uniqueness of pineal germinoma. Ocular findings and signs and symptoms of elevated intracranial pressure are the keys to suspecting the diagnosis and obtaining the necessary imaging and cerebrospinal fluid studies. Other symptoms can suggest spread beyond the pineal region. Surgery may only be needed to obtain tissue for a definitive diagnosis, as germinoma is highly responsive to chemotherapy and focused radiation therapy. Hydrocephalus, usually related to tumor obstruction of the cerebral aqueduct, may also need to be addressed. Outcome for pineal germinoma is usually excellent, but relapse can occur and may require additional intervention. These issues are detailed in this review.

Pineal cyst management: A single-institution experience spanning two decades

Background:

Pineal cysts (PCs) are benign lesions commonly found on intracranial imaging. Despite their high prevalence, there is no clear consensus on the most appropriate management of patients with PCs, especially those with symptomatic nonhydrocephalic cysts.

Methods:

A retrospective analysis was performed on 142 patients with PCs (103 surgical cases and 39 conservatively managed cases). Data were examined, including clinical presentation, imaging findings, ophthalmological status, natural course, postoperative outcomes, and complications.

Results:

Surgical group: the most common symptom was headache (92%), followed by signs of intracranial hypertension due to hydrocephalus (22%). New radiological feature of PCs was found in 11 patients. From 71 patients with long-term follow-up, headache completely resolved in 44 (62%) patients; marked improvement was observed in 20 (29%); in 7 (9%) – headache remained unchanged. The most common postoperative complication was neuro-ophthalmological disorders (23%), with a tendency for resolution in the long-term follow-up period. Neuro-ophthalmological symptoms at last follow-up included upward gaze palsy (6%) and skew deviation (5%), followed by convergence disorders (3%) and eyelid-retraction (2%). Natural course group: PC size remained stable in 34 (87%) patients during the follow-up period. The patient’s gender or age was not a significant predictor of cyst growth (P = 0.4, P = 0.56).

Conclusion:

The majority of patients with a newly diagnosed PC remain clinically and radiologically stable. Patients with nonhydrocephalic PCs and intractable headaches experience significant relief in headache symptoms, but are at risk of mild to moderate neuro-ophthalmological disorders. The natural course of PCs and factors promoting their growth still remains poorly defined.

Diagnosis and Treatment of Pineal Region Tumors in Adults: A EURACAN Overview

Simple Summary

Pineal region tumors are rare intracranial tumors. A deeper knowledge of these tumors’ molecular mechanisms has been gained in recent years, which has led to a new classification and new potential systemic treatments. Surgery remains the mainstay of treatment, while radiotherapy and systemic therapy depend on histological, molecular, and clinical characteristics. This paper highlights recent developments in the diagnosis and treatment of these tumors.

Abstract

Pineal region tumors are rare intracranial tumors, accounting for less than 1% of all adult intracranial tumor lesions. These lesions represent a histologically heterogeneous group of tumors. Among these tumors, pineal parenchymal tumors and germ cell tumors (GCT) represent the most frequent types of lesions. According to the new WHO 2021 classification, pineal parenchymal tumors include five distinct histotypes: pineocytoma (PC), pineal parenchymal tumors of intermediate differentiation (PPTID), papillary tumor of the pineal region (PTPR), pinealoblastoma (PB), and desmoplastic myxoid tumor of the pineal region, SMARCB1-mutant; GCTs include germinoma, embryonal carcinoma, yolk sac tumor, choriocarcinoma, teratoma, mixed GCTs. Neuroradiological assessment has a pivotal role in the diagnostic work-up, surgical planning, and follow-up of patients with pineal masses. Surgery can represent the mainstay of treatment, ranging from biopsy to gross total resection, yet pineal region tumors associated with obstructive hydrocephalus may be surgically managed via ventricular internal shunt or endoscopic third ventriculostomy. Radiotherapy remains an essential component of the multidisciplinary treatment approach for most pineal region tumors; however, treatment volumes depend on the histological subtypes, grading, extent of disease, and the combination with chemotherapy. For localized germinoma, the current standard of care is chemotherapy followed by reduced-dose whole ventricular irradiation plus a boost to the primary tumor. For pinealoblastoma patients, postoperative radiation has been associated with higher overall survival. For the other pineal tumors, the role of radiotherapy remains poorly studied and it is usually reserved for aggressive (grade 3) or recurrent tumors. The use of systemic treatments mainly depends on histology and prognostic factors such as residual disease and metastases. For pinealoblastoma patients, chemotherapy protocols are based on various alkylating or platinum-based agents, vincristine, etoposide, cyclophosphamide and are used in association with radiotherapy. About GCTs, their chemosensitivity is well known and is based on cisplatin or carboplatin and may include etoposide, cyclophosphamide, or ifosfamide prior to irradiation. Similar regimens containing platinum derivatives are also used for non-germinomatous GCTs with very encouraging results. However, due to a greater understanding of the biology of the disease’s various molecular subtypes, new agents based on targeted therapy are expected in the future. On behalf of the EURACAN domain 10 group, we reviewed the most important and recent developments in histopathological characteristics, neuro-radiological assessments, and treatments for pineal region tumors.

Exclusively endoscopic management of complicated pineal cysts in young children: Definitive treatment through single burr-hole technique

Background:

The management of complicated symptomatic pineal cysts in the pediatric population is challenging and variable. Surgical management may include treatment of hydrocephalus alone, or direct treatment of the cyst with or without direct hydrocephalus management. This is typically done through craniotomy-based microsurgical approaches to the pineal region or an endoscopic transventricular approach.

Methods:

We present a stepwise minimally invasive technique to treat complicated pineal cysts in young children associated with an obstructive hydrocephalus in a single procedure through third ventriculostomy combined with an intraventricular marsupialization of the pineal cyst through a single burr-hole using stereotactic navigation.

Results:

Two young patients with over 2 years of follow-up have done well without complication using this technique. Other literature reports for complex pineal cysts in pediatric patients are reviewed and this technique is not previously described for this population.

Conclusion:

Endoscopic third ventriculostomy and cyst marsupialization using a single burr-hole and stereotactic navigation for symptomatic or enlarging pineal cysts in children allow for minimally invasive management, a rapid recovery, short hospital stay, and durable outcome owed to redundant CSF flow pathways.

Stereotactic Internal Shunt Placement in Congenital Intracranial Cysts

INTRODUCTION

Treatment of symptomatic intracranial cysts remains a controversial issue. We present a risk/benefit profile of a minimally invasive, not yet described, stereotactic internal shunt implantation technique. The provided data might serve as a reference against which other treatment modalities could be compared.

METHODS

From our prospective database, we identified a consecutive series of patients with symptomatic, untreated cysts who had undergone internal shunting from 2009 to 2017. We estimated the rates of clinical symptom improvement (RCSI), cyst reduction, total complications, and long-term complications. A minimal follow-up of 6 months was required. The prognostic factors were obtained from logistic regression models. Cyst recurrence-free survival was calculated using the Kaplan-Meier method. The outcomes data were compared with those from reported alternative treatment strategies using χ² statistics.

RESULTS

We included 38 patients. The cyst locations differed greatly and included the cerebellum (n = 2), brainstem (n = 5), and pineal area (n = 4). Cyst-associated hydrocephalus (n = 6) resolved after treatment. The 2-year cyst recurrence-free survival rate was 97%. The RCSI and rate of cyst reduction, total complications, and long-term complications was 91%, 97%, 11%, and 2.6%, respectively. We did not find any risk factors associated with the rate of total complications. The RCSI and rate of total and long-term complications compared favorably (P < 0.01) with the corresponding estimates of alternative treatments (P < 0.01).

CONCLUSIONS

The described stereotactic internal shunt implantation technique is safe and can be successfully applied for treatment of cystic formations in any location in the brain.

Results of surgery in symptomatic non-hydrocephalic pineal cysts: role of magnetic resonance imaging biomarkers indicative of central venous hypertension

BACKGROUND

We have previously proposed that pineal cysts (PCs) may result in crowding of the pineal recess, causing symptoms due to compression of the internal cerebral veins and central venous hypertension. In the present study, we compared clinical outcome of different treatment modalities in symptomatic individuals with non-hydrocephalic PCs.

METHODS

The study included all patients managed surgically for non-hydrocephalic PCs in our Department of Neurosurgery over a 10-year period. We applied a questionnaire to determine occurrence of symptoms before and after surgery, which allowed the use of a grading scale for symptom severity. Magnetic resonance imaging (MRI) biomarkers indicative of central venous hypertension were assessed before and after surgery.

RESULTS

Relief of symptoms after surgery was most efficiently obtained by complete microsurgical cyst removal [n = 15; no (0/15), some (1/15) or marked (14/15) improvement], and to a lesser extent by microsurgical cyst fenestration [n = 6; no (2/6), some (4/6) or marked (0/6) improvement]. Shunt surgery was not successful [n = 6; no (5/6), some (1/6) or marked (0/6) improvement]. In all patients, the proposed MRI biomarkers gave evidence of central venous hypertension (PC grades 2-4).

CONCLUSIONS

Microsurgical cyst removal provided marked symptom relief in symptomatic individuals with non-hydrocephalic PCs and MRI biomarkers of central venous hypertension. The hypothesis that PC-induced crowding of the pineal recess may compromise venous run-off and induce a central venous hypertension syndrome deserves further study.

[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.

Interest and limits of endoscopic approaches for pineal region tumours

Endoscopy of pineal region tumours has been developed since the year 2000 either via a transventricular or extracerebral approach. The initial purpose of applying neuroendoscopy in the management of pineal region tumours was to resolve the obstructive hydrocephalus, and identify the pathological characteristics of the tumour. Based on this approach, a piecemeal resection of the tumour can be performed. The approaches, derived from the microsurgical pathway using an endoscope to expose the operative field, have been proposed either via an infratentorial supracerebellar approach or posterior transtentorial interhemispheric approach. Neuroendoscopic procedures can be considered as a therapeutic alternative to the microsurgical approach when CSF markers are negative. This procedure is considered mini-invasive for the approach along the surgical corridor access but extensive and in depth at the interface between the tumour and the surrounding neurological parenchyma. The limitations and complications are related to the type of procedure (mono- or bimanual) as well as the tumoral characteristics. Different approaches are presented in detail in order to avoid the occurrence of any surgical complications.