Meningiomas Originated at the Falcotentorial Region: Analysis of Topographic and Diagnostic Features Guiding an Optimal Surgical Planning

et al. 2020

BMC Neurol

Background: A series of patients harboring pineal region meningiomas were respectively analyzed to explore the origin of these tumors and the true meaning of the term "velum interpositum (VI) meningiomas". Methods: 21 patients with pineal meningiomas underwent operation in Nanfang Hospital of Southern Medical University from January 2005 to December 2016 were retrospectively included to analyze the clinical features, imaging findings and surgical video data of these patients. According to the method of literature, the data of this group were also divided into falcotentorial (FT) meningiomas and VI meningiomas, and the differences between the two types of tumors were compared. Results: Among the 21 cases of tumor, there were 12 cases of FT meningiomas, including 4 cases originating from cerebral falx, 4 cases from tentorium of cerebellum and 4 cases from straight sinus; there were 9 cases of VI meningiomas, 7 of which originated from the arachnoid sleeve of the Galen vein, 1 from the posterior part of the internal cerebral vein and 1 from the posterior surface of the pineal gland. Postoperative pathological examination showed meningiomas in all the 21 patients, including 16 cases of total resection and 5 cases of subtotal resection. Postoperatively limitation of binocular vertical motion was found in 3 cases, homotropic hemianopia in 7 cases, hemiplegia in 1 case and death in 1 case. Conclusions: This study suggests that pineal meningiomas are more suitable to be described by FT meningioma and meningiomas of the arachnoid of the pineal region by analyzing the origin of tumors. The term "VI meningiomas" can only reflect a part of meningiomas of the arachnoid of the pineal region. Before the removal of pineal meningiomas, more attention should be paid to the effects of the two types of tumors on the Galen vein and the straight sinus, and the establishment of venous collateral circulation.

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Reinvestigation of the origins of pineal meningiomas based on its related veins and arachnoid membranes

et al. 2020

BMC Neurol

“…Meningiomas in pineal region are rare, accounting for 0.3%-1.0% of intracranial meningiomas and 2%-8% of pineal region tumors [6,7]. At present, the classification of pineal meningiomas into FT meningiomas and VI meningiomas is generally accepted.…”

Section: Discussionmentioning

confidence: 99%

“…It had been reported that there were two spatial relationships between tumors and veins, either in the anterior 9 superior part of the ICVs and the GV, or in the posterior inferior part of these veins [10]. However, Blasco proposed dividing FT meningiomas into 4 subtypes according to the Bassiouni classification and its relationship with the deep venous system: (A) FTM type I with inferior venous displacement, (B) FTM type II with superior venous displacement, (C) FTM type III with contralateral venous displacement, and (D) FTM type IV with growth over the straight sinus and superolateral venous displacement [7,14]. In addition to the above spatial relationships the veins could be encapsulated totally by the tumor in the present group of patients (Fig.…”

Section: Discussionmentioning

confidence: 99%

Reinvestigation of the origins of pineal meningiomas based on its related veins and arachnoid membranes

et al. 2020

Preprint

Background : A series of patients harboring pineal region meningiomas were respectively analyzed to explore the origin of these tumors and the true meaning of the term "velum interpositum (VI) meningiomas". Methods: 21 patients with pineal meningiomas underwent operation in Nanfang Hospital of Southern Medical University from January 2005 to December 2016 were retrospectively included to analyze the clinical features, imaging findings and surgical video data of these patients. According to the method of literature, the data of this group were also divided into falcotentorial (FT) meningiomas and VI meningiomas, and the differences between the two types of tumors were compared. Results: Among the 21 cases of tumor, there were 12 cases of FT meningiomas, including 4 cases originating from cerebral falx, 4 cases from tentorium of cerebellum and 4 cases from straight sinus; there were 9 cases of VI meningiomas, 7 of which originated from the arachnoid sleeve of the Galen vein, 1 from the posterior part of the internal cerebral vein and 1 from the posterior surface of the pineal gland. Postoperative pathological examination showed meningiomas in all the 21 patients, including 16 cases of total resection and 5 cases of subtotal resection. Postoperatively limitation of binocular vertical motion was found in 3 cases, homotropic hemianopia in 7 cases, hemiplegia in 1 case and death in 1 case. Conclusions : This study suggests that pineal meningiomas are more suitable to be described by FT meningioma and meningiomas of the arachnoid of the pineal region by analyzing the origin of tumors. The term "VI meningiomas" can only reflect a part of meningiomas of the arachnoid of the pineal region. Before the removal of pineal meningiomas, more attention should be paid to the effects of the two types of tumors on the Galen vein and the straight sinus, and the establishment of venous collateral circulation.

“…It had been reported that there were two spatial relationships between tumors and veins, either in the anterior superior part of the ICVs and the GV, or in the posterior inferior part of these veins [11]. However, Blasco proposed dividing FT meningiomas into 4 subtypes according to the Bassiouni classification and its relationship with the deep venous system: (A) FTM type I with inferior venous displacement, (B) FTM type II with superior venous displacement, (C) FTM type III with contralateral venous displacement, and (D) FTM type IV with growth over the straight sinus and superolateral venous displacement [7,14]. In addition to the above spatial relationships the veins could be encapsulated totally by the tumor in the present group of patients.…”

Section: Discussionmentioning

confidence: 99%

Reinvestigation of the origins of pineal meningiomas based on its related veins and arachnoid membranes

et al. 2019

Preprint

Background: A series of patients harboring pineal region meningiomas were respectively analyzed to explore the origin of these tumors and the true meaning of the term "velum interpositum (VI) meningiomas".Methods: 21 patients with pineal meningiomas underwent operation in Nanfang Hospital of Southern Medical University from January 2005 to December 2016 were retrospectively included to analyze the clinical features, imaging findings and surgical video data of these patients. According to the method of literature, the data of this group were also divided into falcotentorial (FT) meningiomas and VI meningiomas, and the differences between the two types of tumors were compared.Results: Among the 21 cases of tumor, there were 12 cases of FT meningiomas, including 4 cases originating from cerebral falx, 4 cases from tentorium of cerebellum and 4 cases from straight sinus; there were 9 cases of VI meningiomas, 7 of which originated from the arachnoid sleeve of the Galen vein, 1 from the posterior part of the internal cerebral vein and 1 from the posterior surface of the pineal gland. Postoperative pathological examination showed meningiomas in all the 21 patients, including 16 cases of total resection and 5 cases of subtotal resection. Postoperatively limitation of binocular vertical motion was found in 3 cases, homotropic hemianopia in 7 cases, hemiplegia in 1 case and death in 1 case.Conclusions: This study suggests that pineal meningiomas are more suitable to be described by FT meningioma and primary pineal meningiomas by analyzing the origin of tumors. The term "VI meningiomas" can not accurately reflect the origin of pineal meningiomas. Before the removal of pineal meningiomas, more attention should be paid to the effects of the two types of tumors on the Galen vein and the straight sinus, and the establishment of venous collateral circulation.