Burak Sade

The natural history of intracranial meningiomas

OBJECT Despite the increased detection of incidental or small meningiomas, the lesions natural history is largely unknown. METHODS One year or longer of follow-up was conducted in 244 patients with 273 meningiomas managed conservatively by a single surgeon between 2003 and 2008. Data were stratified according to age, sex, tumor location, symptoms, initial tumor diameter, calcification, MR imaging intensity, and edema. Linear tumor growth was defined as a 2-mm or larger increase in the maximum diameter in any direction of the tumor. Volumetric analysis (ImageJ version 1.43) was also conducted in 154 of 273 meningiomas for which complete radiological data were available in the form of DICOM files throughout the follow-up period. A volume increase greater than 8.2% was regarded as significant because the preliminary volumetry based on 20 randomly selected meningiomas showed that the average SD was 4.1%. RESULTS Linear growth was observed in 120 tumors (44.0%) with a mean follow-up of 3.8 years. Factors related to tumor growth were age of 60 or younger (p = 0.0004), absence of calcification (p = 0.027), MR imaging T2 signal hyperintensity (p = 0.021), and edema (p = 0.018). Kaplan-Meier analysis and Cox proportional hazards regression analysis revealed that age 60 or younger (hazard ratio [HR] 1.54, 95% CI 1.05-2.30, p = 0.026), initial tumor diameter greater than 25 mm (HR 2.23, 95% CI 1.44-3.38, p = 0.0004), and the absence of calcification (HR 4.57, 95% CI 2.69-8.20, p < 0.0001) were factors associated with a short time to progression. Volumetric growth was seen in 74.0% of the cases. Factors associated with a higher annual growth rate were male sex (p = 0.0002), initial tumor diameter greater than 25 mm (p < 0.0001), MR imaging T2 signal hyperintensity (p = 0.0001), presence of symptoms (p = 0.037), and edema (p < 0.0001). CONCLUSIONS Although the authors could obtain variable results depending on the measurement method, the data demonstrate patients younger than 60 years of age and those with meningiomas characterized by hyperintensity on T2-weighted MR imaging, no calcification, diameter greater than 25 mm, and edema need to be observed more closely. Volumetry was more sensitive to detecting tumor growth than measuring the linear diameter.

World Health Organization Grades II and III meningiomas are rare in the cranial base and spine.

OBJECTIVEThis study was undertaken to assess a possible relationship between the tumor location and the incidence of World Health Organization (WHO) Grades II and III meningiomas. METHODSA retrospective review of 794 consecutive patients who underwent meningioma resection between January 1991 and March 2004 was conducted. Among these, 47 patients (5.9%) with WHO Grade II meningiomas and 16 patients (2%) with Grade III meningiomas were further analyzed. Tumor location was assessed using preoperative magnetic resonance imaging scans and/or operative reports. Histological grading was done according to the WHO 2000 Classification scheme. RESULTSWHO Grade II tumors were found in eight out of 289 (2.8%) cranial base meningiomas and in zero spinal meningiomas, compared with 39 out of 429 (9.1%) non-cranial base meningiomas. Grade III histology was encountered in two (0.7%) cranial base tumors and in one out of 76 (1.3%) spinal tumors, compared with 13 (3%) non-cranial base tumors. The combined incidence of Grades II and III meningiomas was significantly lower in the cranial base (3.5%) and spinal (1.3%) locations compared with non-cranial base locations (12.1%) (P < 0.001). CONCLUSIONWHO Grades II and III meningiomas occur far less frequently in the cranial base and spinal locations. Tumors arising from these locations may have different mechanisms of tumorigenesis and/or progression compared with meningiomas arising from other (non-cranial base) regions.

High incidence of optic canal involvement in tuberculum sellae meningiomas: rationale for aggressive skull base approach.

BACKGROUND Current literature on TSMs underemphasizes the significance of OCI by the tumor. In this study, we aimed to document the incidence of OCI, its management using a SBT, and its significance with relation to the visual outcome. METHODS Thirty-one patients with TSM were retrospectively analyzed. In 28 patients, SBT consisting of extradural anterior clinoidectomy with falciform ligament and optic nerve sheath opening was performed. Pre- and postoperative visual status was analyzed with respect to OCI. RESULTS The incidences of OCI and preoperative visual deficit (VD) were 77.4% and 83.8%, respectively. With regard to preoperative visual status, OCI incidence was 84.6% in 26 patients with VD compared to 40% in 5 patients without (P = .016). Among the 23 patients with VD and detailed postoperative neuroopthalmologic evaluation, 78.3% had visual improvement; and in 21.7%, vision was unchanged on the operated side. In one patient (3.2% in the whole series), vision deteriorated on the side contralateral to the side of surgery. In the presence of OCI in 20 patients, vision improved in 80% and remained unchanged in 20%, whereas 1 of the 3 patients without OCI improved and the other 2 remained unchanged. Simpson grade I or II resection was achieved in 83.8%. CONCLUSION Optic canal involvement is very common in TSM (77.4%), and it correlates well with preoperative visual status. With the use of SBT, without which the tumor in the optic canal could not have been removed completely and safely, visual improvement of 78.3% and stability of 21.7% were achieved on the operated side.

Outcomes of minimally invasive endoscopic resection of anterior skull base neoplasms.

The objective of this study was to review clinical outcomes of minimally invasive endoscopic resection (MIER) for anterior skull base (ASB) neoplasms.

A Surgical Technique for the Removal of Clinoidal Meningiomas

CLINOIDAL MENINGIOMAS, ALSO referred to as medial or inner sphenoid wing meningiomas, are often difficult and challenging to remove completely and safely, especially when they become large enough to encircle, compress, or displace the adjacent critical neurovascular structures such as the optic nerve, the internal carotid artery and its branches, and the oculomotor nerve. In this article, the authors describe the detailed surgical technique used in their practice in addition to subtle nuances learned from their experience of operating on more than 40 patients with clinoidal meningiomas over the past several years. The primary goals of surgery are to achieve aggressive tumor removal with avoidance of intraoperative morbidity and, in addition, for those with preoperative compromised vision, to provide improvement in their visual function after surgery.

New prospects for management and treatment of inoperable and recurrent skull base meningiomas

Skull base, including optic nerve, cavernous sinus, clival and foramen magnum tumors represent a major challenge for neurosurgeons and neuro-oncologists. Growth regulatory signaling pathways for these tumors are of increasing interest as potential targets for new chemotherapy. Those differentially activated in various grades of meningiomas are currently being identified as well. This article reviews some recent findings pathways that appear to regulate meningioma growth. Potential targets for novel therapies are also discussed.

Progression of terminal syrinx in occult spina bifida after untethering.

Abstract Object. The association of spinal dysraphism and terminal syringomyelia is a well-known entity, and untethering with or without syrinx drainage is usually the surgery of choice. However, progression of the previously existing syrinx after an untethering procedure is an uncommon course. The objective of this study was to discuss the diagnostic, surgical, and follow-up consequences of such an occurrence. Methods. Four children with occult spina bifida associated with terminal syrinx at the time of initial presentation are included in this study. After the primary releasing procedure, all developed enlargement of the syrinx. Two of them were operated on for placement of a syringo-subarachnoid shunt, while the other two were followed up conservatively. One of the shunted patients also had a second releasing procedure. Conclusion. Progression of the pre-existing terminal syrinx after the primary untethering procedure should be kept in mind even in the absence of overt neurological progression.

Depressed skull fracture and epidural haematoma: an unusual post-operative complication of pin headrest in an adult

SummaryDepressed skull fracture and epidural haematoma caused by pin headrest complicated the post-operative course in an adult, after removal of a parasagittal meningioma. The calvarial thickness was observed to be significantly reduced due to chronic high intracranial pressure. Potentially hazardous complications of pin headrests should not be underestimated in adults.

Neuromuscular hamartoma of the trigeminal nerve in an adult

SummaryA 36-year-old female presented with a long-standing history of headache. Computed tomography scan and magnetic resonance imaging revealed an enhancing lesion occupying the right Meckel’s cave, enlarging the trigeminal ganglion and extending through the foramen ovale into the infratemporal fossa. A right frontotemporal extradural approach to the cavernous sinus was performed and a firm, pinkish lesion intermingled with nerve fibers enlarging the trigeminal ganglion and V3 branch was identified. Frozen section was suggestive of a neuromuscular hamartoma. The lesion was sub-totally resected to avoid injury to the motor branch.Neuromuscular hamartoma should be included in the differential diagnosis of cavernous sinus and cranial nerve lesions in adults.

High incidence of optic canal involvement in clinoidal meningiomas: rationale for aggressive skull base approach

IntroductionLiterature specifically focusing on clinoidal meningiomas is scant, particularly with regards to the postoperative visual outcome. In this study, we aimed to document the incidence of optic canal involvement (OCI) by the tumor, its management using a skull base technique, and its significance with relation to the visual outcome.Materials and methodsFifty-two patients with clinoidal meningiomas were retrospectively analyzed. In 47 patients, skull base technique consisting of extradural anterior clinoidectomy with falciform ligament and optic nerve sheath opening was performed. Pre-operative visual status and post-operative outcome were analyzed with respect to OCI.ResultsThe incidences of OCI was present in 19 (36%) and pre-operative visual deficit (VD) in 24 (46%) patients. With regard to pre-operative visual status, OCI was seen in 14 (58%) of 24 patients with VD, as compared to five (18%) in 28 patients without (p = 0.004). Among the 22 patients with VD and detailed postoperative neuro-ophthalmological evaluation, 17 (77%) had visual improvement, and in five patients (23%), vision was unchanged. In the presence of OCI in 11 patients, vision improved in seven (64%), and remained unchanged in four patients (36%), whereas all but one of the 11 patients (91%) without OCI improved and in the remaining one (9%), remained unchanged. Simpson Grade I and II resection was achieved in 71%.ConclusionOCI is observed in 36% of clinoidal meningiomas, and it correlates well with pre-operative visual status. With the use of the skull base technique, without which the tumor in the optic canal could not have been removed completely and safely, visual improvement of 77% and stability of 23% was achieved.