Microsurgical Resection of a Pineal Cyst via a Paramedian Supracerebellar Infratentorial Approach.

Pineal cysts are typically detected in around 1.3% to 4.3% of patients during routine magnetic resonance imaging (MRI) scans.1,2 The vast majority of pineal cysts are benign, asymptomatic, and typically do not necessitate surgical intervention. Large pineal cysts are known to cause hydrocephalus with its associated symptoms and thus can require in rare cases surgical resection. Even in the absence of hydrocephalus, selected patients with large pineal cysts causing headaches and visual disturbances can find relief after surgical resection.3,4 The supracerebellar infratentorial (SCIT) approach is widely used and represents an extraparenchymatous approach through a natural corridor to the pineal region.5 Performing this approach in a semisitting position allows for an optimal retraction of the cerebellum by gravity. We employ a minimally invasive paramedian SCIT approach for the resection of pineal cysts. In our experience, the paramedian SCIT approach allows for a less steep operating angle and a smaller craniotomy compared with the midline SCIT approach. We present a 24-year-old female complaining of headache. The initial MRI was conducted 2 years before surgery. Following the initial evaluation, the patient experienced progressive headaches without neurologic deficits. A subsequent MRI revealed enlargement of the pineal cyst, leading to the indication for surgical resection. The surgery was performed mainly under the operating microscope with endoscopic visualization in suitable situations as our small approach restricts bimanual dissection with an endoscope. In our experience, this approach provides a versatile and minimally invasive access to the pineal region, making it optimally suitable for pineal cysts requiring surgical resection.

Papillary Tumors of Pineal Region: A Single-Center Experience in Management of 11 Cases.

BACKGROUND: Papillary tumors of pineal region (PTPR) comprise a very rare subset of pineal region tumors that have been recently described. Literature on the management and outcome of PTPR is scarce owing to the rarity of these tumors. To address this lacuna, we analyzed our experience in management of PTPR. METHODS: We retrospectively analyzed the outcome of 11 patients with histopathologically proven PTPR who underwent surgical excision at our center. RESULTS: Mean patient age was 33.3 years (range, 12-45 years), and male-to-female ratio was 1.75:1. Headache was the most common presentation followed by visual disturbances, altered sensorium, Perinaud syndrome, and seizures. Cerebrospinal fluid diversion was required in 6 patients. Krause approach was the most common approach used for tumor excision (9/11 cases). There was no perioperative mortality. Two patients were lost to follow-up. In the remaining 9 patients, the average follow-up period was 45 months (range, 12-79 months). On first postoperative magnetic resonance imaging, 8 patients showed no evidence of residual tumor (gross total resection), while 1 patient had small residual tumor (near-total resection) that remained stable during follow-up. Four patients underwent adjuvant chemoradiotherapy. None of the patients developed recurrence during follow-up. CONCLUSIONS: PTPR are a rare subgroup of pineal region tumors with distinct cells of origin but presentation similar to other pineal region tumors. Surgical resection constitutes the mainstay of management, and the extent of resection appears to be the most important determinant of prognosis. The role of adjuvant therapy still needs to be determined.

Microsurgical Treatment of Pineal Tumors: Anatomy and Techniques.

Pineal region tumors are challenging lesions in terms of surgical accessibility and removal.1 The complexity is compounded by the infrequency and heterogeneity of pineal neoplasms.2,3 In Video 1, we present the case of a 39-year-old woman who presented with progressive headaches and vision impairment. She underwent microsurgical resection for a pineal parenchymal tumor of intermediate differentiation. We discuss the rationale, risks, and benefits of treatment for this patient, as well as provide a detailed overview of the alternative approaches that may be considered. Additionally, we discuss the unique anatomic considerations for each approach and include a virtual reality-compatible 3-dimensional fly-through to highlight the relationship between the tumor and relevant venous anatomy. The patient tolerated the procedure well with excellent neurologic outcome, and her follow-up imaging showed no evidence of tumor recurrence.

An atypical location of pineoblastoma RB1 subgroup without pineal or retinal tumor.

PURPOSE: To describe the clinical and imaging features of a sellar-suprasellar pineoblastoma RB1 subgroup without pineal or retinal involvement. CASE REPORT: An 11-month-old girl presented to the emergency department with fever, rhinorrhea, vomiting, altered level of consciousness, and one seizure. Head CT and brain MRI demonstrated a large lobulated mass with calcifications and heterogeneous enhancement in the suprasellar region causing mass effect to the ventricular system and hydrocephalus. Histology revealed a CNS embryonal tumor not otherwise specified (NOS) with small round nuclei with mitotic activity and necrosis. DNA methylation analysis classified the tumor in the pineoblastoma RB1 subgroup. CONCLUSION: Pineoblastoma RB1 subgroup should be considered in the differential diagnosis of large sellar-suprasellar masses with calcifications and heterogeneous enhancement in children younger than 18 months even in cases of absent pineal or retinal involvement. Molecular analysis with DNA methylation profiling is critical for diagnosis and management.

Pineal cysts in children: a paediatric series treated over the last twenty years in Lyon.

BACKGROUND: Pineal cysts are a rare lesion of the pineal gland. Pineal cysts are benign lesions, generally asymptomatic, and are usually an incidental discovery on MRI performed for other problems. The management of pineal cysts in children remains a matter for debate. Here, we report our own retrospective paediatric cases that have been surgically treated and review the paediatric literature on this topic. METHODS: This is a retrospective monocentric study. All patients operated by the senior author (CM) for a benign pineal cyst from 2000 to 2021 were included. All other pineal region cystic lesions were excluded. Medical and surgical data were extracted from the hospital medical database. RESULTS: Twelve patients were included. The clinical symptomatology was characterized by headaches in seven patients, visual troubles in two patients, precocious puberty in one patient, signs of intracranial hypertension in two patients, seizures associated with headache in one patient, and headaches associated with behavioural troubles in another patient. No major post-operative complications were observed in this series. It is to noted that surgery was performed because a suspicion of a true pineal parenchymal tumour has been made. Histopathological study came back with the diagnosis of pineal cyst. CONCLUSIONS: Pineal cyst is rare. If the radiological diagnosis is clear, no surgery is advocated except in cases associated with hydrocephalus and rapid growth. In case of a suspicion of a true pineal parenchymal tumour, a surgery may be needed to confirm the diagnosis. Lastly, we stress that only cystic lesions of the pineal gland itself should be considered as pineal cyst.

The surgical intervention for pineal region tumors.

Histological and molecular characterization is essential for the diagnosis of pediatric brain tumors. In the pineal region tumors, it is necessary to remove a sufficient tumor volume to make a diagnosis. However, surgery in this region is challenging due to its deep anatomical location and surrounded by critical structures and complex venous system. Knowledge of the anatomy and function of the pineal region and tumor histological types is imperative for the successful management of pineal region tumors. This article describes surgical approaches to pineal tumors, focusing on the occipital transtentorial approach and adding the author's experience to what has been known in the literature. Recent innovations have made this approach more popular and can be applied to occipital fossa lesions.

Paediatric pineal region cysts: enigma or impaired neurofluid system?

PURPOSE: Pineal region cysts (PCs) may affect the tectum and aqueduct and cause deep central vein congestion. Beside headaches, PC often causes a broad range of symptoms, leading to prolonged diagnosis and therapy. The aims of this study are to reveal parameters that might explain the ambiguity of the symptoms and to identify factors in association with the respiration-driven neurofluid system. METHODS: This retrospective study included 28 paediatric patients (mean age 11.6 years) who received surgical treatment and 18 patients (mean age 11.3 years) who were followed conservatively. Symptoms, time to diagnosis, cyst size, ventricular indices, head circumference and postoperative outcome, were analysed. Four patients were investigated for CSF dynamics with real-time MRI. The mean follow-up time was 1.6 years. RESULTS: The most common early onset symptoms were headaches (92%), blurred vision (42.8%), sleep disturbances (39.3%) and vertigo (32.1%). Tectum contact was observed in 82% of patients, and MRI examinations revealed that imaging flow void signals were absent in 32.1% of patients. The maximal cyst diameters were 13.7 × 15.6 mm (mean). Together with a postoperative flow void signal, 4 patients recovered their respiration-driven CSF aqueductal upward flow, which was not detectable preoperatively. After surgery the main symptoms improved. CONCLUSION: Despite proximity to the aqueduct with frequently absent flow void signals, hydrocephalus was never detected. Data from real-time MRI depicted a reduced preoperative filling of the ventricular CSF compartments, indicating a diminished fluid preload, which recovered postoperatively.

Accuracy of apparent diffusion coefficient values for distinguishing between pineal germ cell tumour and pineoblastoma.

AIM: To differentiate between pineal germ cell tumour and pineoblastoma using apparent diffusion coefficient (ADC) values due to their overlapping imaging findings on magnetic resonance imaging (MRI). MATERIALS AND METHODS: This retrospective study was conducted on 33 patients with pineal germ cell tumours and eight patients with pineoblastoma who underwent pretreatment MRI. Twenty-seven patients (21 with pineal germ cell tumour and six with pineoblastoma) were included for ADC measurement. The minimum and mean ADC values of the tumours were measured, with normalized tumour to control ADC ratios generated. The MRI characteristics of the tumours were evaluated. RESULTS: The mean and minimum ADC values, normalized mean and minimum ADC ratios of pineal germ cell tumours were significantly higher than those of pineoblastomas (all p<0.005). A cut-off value of 0.92 for the normalized mean ADC ratio was used to distinguish between pineal germ cell tumour and pineoblastoma and achieved an area under the curve of 0.95, sensitivity of 90.5%, specificity of 83.3%, and accuracy of 92.6%. An equal degree of contrast enhancement to the adjacent venous sinus was the only MRI characteristic that suggested the diagnosis of pineal germ cell tumour. CONCLUSION: The ADC values could help differentiate between pineal germ cell tumour and pineoblastoma, specifically when conventional MRI findings are indeterminate.

Exoscopic supracerebellar approach to the pineal region.

The advent of the 3D exoscope represents a significant technological breakthrough in contemporary surgical practice. While the operating microscope has long been the preferred surgical visualization tool, its limitations in accessibility and ergonomics have prompted the development of a more advanced, 3D version [1,2]. The 3D exoscope has been one such recent development aimed at addressing these limitations. By delivering intense illumination and magnification to the deepest parts of the surgical field, 3D exoscopes are high-definition digital camera systems that give surgeons high-magnification views of the operative field [2]. Additionally, the design of the 3D exoscope allows for improved surgeon ergonomics, decreasing overall fatigue while providing a similar view of the procedure for all personnel in the operating room [3,4]. In this article, we discuss the advantages and limitations of the 3D exoscope in neurosurgery and highlight its use in a patient case. This is a case of a 25-year old female who was noted to have an incidental 13 mm pineal cystic mass on imaging work up for a first time generalized seizure. We discuss the use of an exoscopic supracerebellar approach to the pineal gland for resection of the mass and highlight the various considerations for use of an exoscope in such a case.

Cross-sectional analysis of potential risk factors of the pineal gland calcification.

The Pineal gland (PG) is the site of production of melatonin as an important central hormone in the body. It is not known yet whether PG calcification (PGC) is an age-associated physiological process or a pathologic condition caused by lifestyle-factors and metabolic-dysregulations.Here, we performed a cross-sectional analysis on 586 patients referred to have Computed Tomographic (CT) scans (above 15 years old), in the Ali Ebne Abi Taleb hospital radiology center in 2017-2018. Based on the CT-scans of the brain, the presence of PGC was recorded and a score of scale 0 to 6 (PGC_score) was calculated for its intensity based on the volume and the Hounsfield units of the calcified pineal. Logistic and ordered logistic regression tests were employed to determine potential risk factor of PGC and higher PGC_score, respectively, testing the factors age, sex, history of cardiovascular and metabolic diseases, smoking and opioid use. We found male sex (OR: 2.30 (95% CI:1.39-3.82) and smoking cigarettes (OR: 4.47 (95% CI:1.01-19.78)) as the main potential risk factors for the pineal gland calcification. For PGC_score, we found age to be dose-dependently associated with PGC_score only in patients aged below 63 (p-trend < 0.001). Stratifying for age, in patients < 63 years old, we found age, male sex (positive association) and dyslipidemia (negative association) as the main significantly associated factors of PGC_score. On the contrary, in patients aged > = 63, cigarette smoking was the only significantly associated factor of higher PGC_score.In conclusion, our results indicate that at ages below 63, age, male sex and blood lipid are the main associated factors of higher PGC, but at ages above that, the lifestyle factor smoking is significantly associated with higher pineal gland calcification.

Beyond Visual Assessment of Basal Ganglia Uptake: Can Automated Method and Pineal Body Uptake Assessment Improve Identification of Nigrostriatal Dysfunction on 18F-DOPA PET/CT?

The interpretation of 18F-DOPA PET/CT performed for assessing nigrostriatal dysfunction (NSD) is usually based on visual assessment of the uptake in the basal ganglia (VA-BG). In the present study, we evaluate the diagnostic performance of an automated method that assesses BG uptake (AM-BG) and of methods that assess pineal body uptake, and examine whether these methods can enhance the diagnostic performance of VA-BG alone. We retrospectively included 112 scans performed in patients with clinically suspected NSD who also had a subsequent final clinical diagnosis provided by a movement disorder specialist (69 NSD and 43 non-NSD patients). All scans were categorized as positive or negative based on (1) VA-BG, (2) AM-BG, and (3) qualitative and semiquantitative assessment of pineal body uptake. VA-BG, AM-BG, assessment of pineal body 18F-DOPA uptake by VA (uptake > background), by SUVmax (≥0.72), and by pineal to occipital ratio (POR ≥ 1.57) could all significantly differentiate NSD from non-NSD patients (Pv < 0.01 for all five methods). Of these methods, VA-BG provided the highest sensitivity (88.4%) and accuracy (90.2%). Combining VA-BG with AM-BG did not improve diagnostic accuracy. An interpretation algorithm that combines VA-BG with pineal body uptake assessment by POR calculation increased sensitivity to 98.5%, at the expense of decreased specificity. In conclusion, an automated method that assesses 18F-DOPA uptake in the BG and assessment of pineal body 18F-DOPA uptake can significantly separate NSD from non-NSD patients, with apparent inferior diagnostic performance when applied alone compared with VA-BG. When VA-BG categorizes a scan as negative or equivocal, assessment of the 18F-DOPA uptake in the pineal body has the potential to minimize the rate of false negative reports. Further research is essential to validate this approach and to study the pathophysiologic relationship between 18F-DOPA uptake in the pineal body and nigrostriatal dysfunction.

Human Pineal Gland Involutionary Process: New Findings.

In this work, we report preliminary results about the involution of the human pineal gland involution. The detailed analysis of pineal structure was done on autopsy material of 77 persons in age 27-96 using x-ray phase-contrast tomography, histology, and immunohistochemistry. Our study suggests that the pineal gland alteration in older adults may be more profound than has been reported to date. We identified and described a new form of pineal gland involution that eventually led to the total degradation of the pineal gland. To our knowledge, this study is the first to report on the complete replacement of pineal gland parenchyma with connective tissue in older adults.

The Minimally Invasive Lateral Occipital Infracortical Supra-/Transtentorial Approach in Surgery of Lesions of the Pineal Region: A Possible Alternative to the Standard Approaches.

OBJECTIVE: The pineal region is an anatomical region that is difficult to access surgically, especially when it comes to removing neoplasms. Four main surgical approaches to this region are used as standards nowadays: infratentorial supracerebellar, occipital supra-/transtentorial, interhemispheric, and transventricular approaches. All methods have both advantages and disadvantages and are associated to any extent with intra- and postoperative risks. We have developed a lateral minimally invasive occipital infracortical supra-/transtentorial (OICST) approach, which retains the advantages of the standard occipital transtentorial approach while improving tumor exposure and minimizing its disadvantages. METHODS: We describe 7 consecutive cases of successful complete removals of pineal tumor formations of various quality and size (3 pineal cysts, 2 pineocytomas, 1 meningioma, 1 medulloblastoma) using the OICST approach developed by us. Preoperative 3-dimensional and virtual reality-modeling and the use of a special retractor also contributed to reducing the size of the surgical approach. RESULTS: All patients underwent surgery for removal of a lesion in the pineal region and suffered from no new and permanent neurological deficits postoperatively. The mean size of the craniotomies was 2.3 × 1.85 cm. The minimally invasive approach developed by us carries the advantages of the standard occipital transtentorial approach, but minimizes its disadvantages. The main disadvantage of the standard occipital approach is excessive retraction of the occipital lobe, which is frequently associated with visual neurological deficits. Also, with occipital approach, the Rosenthal vein lying along the surgical corridor is frequently not good visible since the tumor is approached from its tip rather than side which limits the overview of the surgical field and can pose a risk. Damage to this vein can cause infarction of the basal ganglia. By approaching the pineal region from more laterally the size of the craniotomy can significantly be reduced, excessive retraction of the occipital lobe can be avoided and the risk of damage to large deep veins can be minimized. The cosmetic outcome with a small skin incision of only about 3 cm is also a very good side effect of this minimally invasive technique. CONCLUSIONS: The minimally invasive lateral OICST approach described by us can be successfully used in the surgery of pineal neoplasms. Reducing the size of the craniotomy does not limit the possibility of complete removal of tumors of various sizes and tissue consistency, and also minimizes the risks of both intra- and postoperative complications.

Pure endoscopic resection of pineal region tumors through supracerebellar infratentorial approach with 'head-up' park-bench position.

OBJECTIVE: Neuroendoscopic resection via supracerebellar infratentorial (SCIT) approach is adequate for some indicated pineal region tumors with the natural infratentorial corridor. We described this full endoscopic approach through a modified 'head-up' park-bench position to facilitate the procedure. METHODS: We reviewed the clinical and radiological data of four patients with pineal region lesions who underwent pure endoscopic tumor resection through the SCIT approach with this modified position. The related literature concerning fully endoscopic pineal region tumor resection was also reviewed. RESULTS: This cohort included four patients with pineal region tumors. External ventricular drainage (Ommaya reservoir) was performed in three patients with hydrocephalus in advance. The average tumor volume was 19.2 ± 17.2 cm3. Pathological examination confirmed two mixed germinomas, one glioblastoma multiforme, and one hemangioblastoma. Gross total resection (GTR) was achieved in all patients, and all patients recovered well without neurological deficits or surgical complications. Hydrocephalus was relieved among all patients. CONCLUSIONS: The pure endoscopic SCIT approach could enable safe and effective resection of pineal region tumors, even for relatively large lesions. The endoscope could provide a panoramic view and illumination of the deep-seated structures. Compared with the sitting position, this modified ergonomic position could be implemented easily.

Differentiation between germinoma and other pineal region tumors using diffusion-and susceptibility-weighted MRI.

PURPOSE: To evaluate the effectiveness of diffusion-weighted imaging (DWI) and susceptibility-weighted imaging (SWI) for differentiation between germinoma and other pineal region tumors. METHOD: This retrospective study consisted of 72 patients with pathologically proven pineal region tumors between January 2010 and August 2020. Tumors were classified as germinomas (40), non-germinomatous germ cell tumors (11) (NGGCT), pineal parenchymal tumors (10) (PPT), and other types of tumors (11). Visual scale score, ADC values and SWI intratumoral susceptibility signal (ITSS) score were analyzed and compared to histopathology data. RESULTS: The mean apparent diffusion coefficient (ADCmean) and minimum apparent diffusion coefficient (ADCmin) ratio of germinoma were significantly lower than NGGCT. ADCmean or ADCmin cut-off ratio of ≤ 1.48 or ≤ 1.32 allowed for discrimination between germinoma and NGGCT with sensitivity and specificity of 100 % and 63.6 %. An ADCmin cut-off ratio of ≥ 0.93 allowed for discrimination between germinoma and PPT with sensitivity and specificity of 60 % and 80.0 %. ADCmin cut-off ratio of ≤ 1.15 allowed for discrimination of germinoma from other types of tumors with sensitivity and specificity of 87.5 % and 54.5 %. CONCLUSIONS: ADC ratio can differentiate germinoma from other types of pineal region tumors. Our initial results suggest that ITSS score was not significantly correlated with specific histology subtype.

Extensive Drop Metastases From Pineal Gland Tumor: A Case Report.

ABSTRACT: Pineal gland tumors are an infrequent central nervous system manifestation. Their prevalence is only less than 1% of all central nervous system tumors. They generally involve children or young adults aged younger than 40 years. Extracranial or spinal drop metastases are very rare from pineal gland tumors. In this case, 18 FDG PET/CT demonstrates drops in metastases involving the entire length of the spinal as well as multiple other intracranial metastatic lesions.

Pediatric pineal region masses: a single-center experience over 25 years.

PURPOSE: Pineal region tumors (PRT) represent less than 1% of brain neoplasms. The rare and heterogeneous nature of these tumors is reflected in the variety of treatment modalities employed. METHODS: A single-center retrospective review of all pediatric patients with pineal region tumors between November 1996 and June 2021 was performed. Fifty-six cases of pineal tumors were reviewed for age and symptoms upon presentation, diagnostic methods, imaging characteristics, histological classification, treatment modalities, recurrence, and mortality rates. RESULTS: The average age at diagnosis was 11.3 years. The majority of patients were male (82.1%) and Caucasian (73.2%). The most common presenting symptoms were headache (n = 38, 67.9%) and visual problems (n = 34, 60.7%). Hydrocephalus was present in 49 patients (87.5%). Germinoma (n = 20, 35.7%) and non-germinomatous germ cell tumor (NGGCT) (n = 17, 30.4%) were the most common tumors. Chemotherapy was employed for 54 patients (96.4%), radiation for 49 (87.5%), and surgical resection for 14 (25.0%). The average duration of treatment was 5.9 months. Progression-free survival was 74.4% at 5 years and 72.0% at 10 years. Overall survival was 85.7% at 5 years and 77.1% at 10 years. CONCLUSION: Treatment of pineal region tumors must be targeted to each patient based on presentation, subtype, presence of hydrocephalus, and extent of disease. Upfront surgical resection is usually not indicated. As advances in oncological care proceed, treatment modalities may continue to improve in efficacy.