Tentorial meningiomas: surgical options, clinical feature and management experience in 43 patients

Catastrophic Outcome Following Apparently Trivial Nondominant Transverse Sinus Injury During Resection of a Tentorial Meningioma: Case Report

A 52-year-old man was admitted to our hospital with symptoms of raised intracranial pressure and cerebellar dysfunction caused by a medium-sized (4 cm in diameter) tentorial meningioma with an infratentorial extension. Preoperative magnetic resonance imaging showed that the tumor indented and possibly partially invaded the adjacent junction of the nondominant transverse and sigmoid sinuses. The contralateral dominant transverse sinus was fully patent. Total surgical removal of the lesion was done through the left retrosigmoid approach. During dissection of the meningioma, some bleeding from the venous sinus was noted, which was easily controlled by packing with hemostatic materials. The initial postoperative period was unremarkable, but approximately 48 h after surgery, acute clinical deterioration caused by hemorrhagic venous infarction of the left cerebellar hemisphere and brain stem developed and necessitated urgent reoperation for the evacuation of hematoma and brain decompression. Thereafter, the patient remained in a prolonged coma with a severe neurological deficit. After several years of extensive neurorehabilitation, he was able to walk with support but had a tracheostomy, required a feeding tube, and voided with a urinary catheter. Such a catastrophic outcome after an apparently trivial nondominant transverse sinus injury during resection of a tentorial meningioma raises the question whether reconstruction of the sinus wall with preservation of its patency might have prevented this complication in our patient.

Surgical management of tentorial meningiomas: case series

Background

There are several surgical strategies involved in the treatment of patients with tentorial meningioma, and choosing the most appropriate one is not straight forward. Our study aims to illustrate our experience in the management of tentorial meningiomata at our center.

Results

This study included 32 patients with tentorial meningiomas, operated upon, with assessment of the extent of resection and the Glasgow outcome score (GOS). The mean age at the time of surgery for the studied group was 48.4 years ranging from 20 to 70 years. Total removal was considered as Simpson grade I or II and was achieved in 26 cases (81.25%). Subtotal removal was considered as Simpson grade III or IV and was achieved in 6 cases (18.75%). The final Glasgow outcome score (GOS) for all cases was GOS 1 in 4 cases (12.5%), GOS 4 in 9 cases (28.2%), and GOS 5 in 19 cases (59.3%).

Conclusion

Tentorial meningiomas can be very challenging during surgery due to their proximity to vital structures. Subtotal resection should be considered when total removal can be hazardous to the patient or result in severe morbidity.

Surgical Management of Tentorial Notch Meningioma Guided by Further Classification: A Consecutive Study of 53 Clinical Cases

Background

Management of tentorial notch meningiomas (TNM) remains a challenge for neurosurgeons. We demonstrate the clinical characteristics and surgical experiences of TNM based on our cases according to a proposed further classification.

Methods

We retrospectively analyzed clinical and follow-up data in a consecutive series of 53 TNM patients who underwent microsurgical operation from 2011 to 2019 in our institution. The operations were performed using various approaches. Clinical history, preoperative and postoperative neurofunction, imaging results, and surgical outcomes were collected for further classification of TNM.

Results

All TNM cases were divided into anterior (T1), middle (T2), and posterior notch (T3). According to the direction of tumor extension and correlation with the neurovascular structures, detailed subtypes of anterior TNMs were identified as the central (T1a), posterior (T1b), and medial type (T1c). The middle TNMs were divided into the infratentorial (T2a), supratentorial (T2b), and supra-infratentorial type (T2c). The posterior TNMs were divided into superior (T3a), inferior (T3b), lateral (T3c), and straight sinus type (T3d) in reference to Bassiouni’s classification. Total removal of the tumor was achieved in 46 cases, with five cases of subtotal and two cases of partial removal without any recorded deaths in our series. In total, five subtotal resected cases underwent gamma-knife treatment and achieved stable disease. Postoperative aggravation or new onset cranial nerve dysfunction occurred in some individual cases, with incidences ranging from 3.77 to 15.10% and improved preoperative neurological deficits ranging from 0 to 100%.

Conclusion

Further, TNM classification based on the intracranial location, extension direction, relationship with brainstem, and neurovascular structures guides preoperative evaluation, rational surgical approach selection, and surgical strategy formulation. Taking microsurgery as the main body, a satisfactory outcome of TNM treatment can be achieved for complicated tumors by combining stereotactic radiotherapy. This study demonstrates the surgical outcomes and complications in detail. Further classification might be helpful for treatment decisions in the future.

Surgical Management of Anterolateral and Posteromedial Incisural Tentorial Meningioma

BACKGROUND

Tentorial meningiomas are a broad and consistent category of tumors but their definition is still unclear and their classification uncertain.

OBJECTIVE

To report the clinical and surgical characteristics of tentorial hiatus meningiomas based on a revised classification of tentorial meningiomas.

METHODS

We reviewed the records of 14 patients who had undergone microsurgical removal of incisural tentorial meningioma. Two tumor subgroups, anterolateral (AL) and posteromedial (PM), were distinguished according to their site of attachment: the middle third and the posterior third of the tentorial free margin, respectively. Clinical presentation, radiological findings, surgical approaches, extent of resection, and outcome were compared.

RESULTS

The 2 subgroups differed by tumor size (larger in PM), incidence of the direction of growth (infratentorial in PM), and hydrocephalus (only in PM), as well as by some clinical aspects. Surgical approach depended on tumor location: lateral (pterional, subtemporal, and retromastoid) for AL lesions; medial (occipital or supracerebellar infratentorial) for PM lesions. Total removal (Simpson grade I-II) was performed in 64% of cases and complications occurred in 14%. Stereotactic radiosurgery was performed in cases of incomplete resection. At a mean follow-up of 104.5 mo, clinical improvement with low recurrence (9%) was achieved.

CONCLUSION

Reallocation of tentorial edge meningiomas is the premise to compare treatment and further improve the approach case-by-case. In spite of their deep site, good outcomes can be achieved in both AL and PM tentorial meningiomas. Also of note is the indolent behavior of residual tumor.

Significance of the Tentorial Alignment in Protecting the Occipital Lobe with the Poppen Approach for Tentorial or Pineal Area Meningiomas

OBJECTIVE

We aimed to identify the factors that can predict the risk of occipital lobe damage preoperatively when resecting tumors located at the tentorial or pineal regions with the occipital-transtentorial approach (Poppen approach).

METHODS

In 27 consecutive patients who underwent tumor resection with the Poppen approach for tentorial or pineal region meningiomas, the following morphologic parameters were assessed on a preoperative magnetic resonance imaging: (1) tentorial angle, (2) tentorial length, and (3) the shortest distance from the confluence of the sinus to the tumor. These parameters, together with tumor size, texture, and resection extent, were correlated with occipital lobe damage by using the one-way analysis of variance, χ², or Fisher's exact tests.

RESULTS

The mean value was 55.3° ± 5.6° (range, 45°-66°) for the tentorial angle, which was significantly associated with the occipital lobe damage grades (P = 0.008), but this was not the case for the tentorial length (P = 0.802) and the shortest distance from the confluence of the sinus to the tumor (P = 0.695). Interestingly, age was also strongly associated with occipital lobe damage risk (P = 0.020). The patients in the subgroup with no occipital damage (grade 4) were the youngest (aged 47.3 years), compared with other grades, with age of 58.0 years for grade 1, 54.3 years for grade 2, and 58.6 years for grade 3. These 2 parameters were also significant after multivariate analysis. No correlation was observed between either tumor nature or the extent of resection and damage grades.

CONCLUSIONS

The risk of occipital lobe damage increases in the presence of a steep tentorial angle during the Poppen approach for tentorial or pineal area tumors. Awareness of such anatomic features preoperatively is important for minimizing operative complications.