Juha E. Jääskeläinen

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Out of 936 primary intracranial meningiomas, 94.3% were histologically benign (grade I), 4.7% atypical (grade II), and 1.0% anaplastic (grade III); one recurrence was sarcomatous (grade IV). Meningiomas with histologic anaplasia (grades II-IV) occurred in 12% of the men, but only 4% of the women. Only 26% of atypical or anaplastic meningiomas appeared(More)
OBJECTIVE To compare carbon 11-labeled Pittsburgh Compound B ([11C]PiB) positron emission tomography (PET) findings in patients with and without Alzheimer disease lesions in frontal cortical biopsy specimens. DESIGN Cross-sectional study of [11C]PiB PET findings in patients with or without beta-amyloid (Abeta) aggregates in frontal cortical biopsy(More)
PURPOSE To prospectively evaluate magnetoencephalography (MEG) and functional magnetic resonance (MR) imaging, as compared with intraoperative cortical mapping, for identification of the central sulcus. MATERIALS AND METHODS Fifteen patients (six men, nine women; age range, 25-58 years) with a lesion near the primary sensorimotor cortex (13 gliomas, one(More)
We studied 12 patients with brain tumors in the vicinity of the sensorimotor region to provide a preoperative three-dimensional visualization of the functional anatomy of the rolandic cortex. We also evaluated the role of cortex-muscle coherence analysis and anatomical landmarks in identifying the sensorimotor cortex. The functional landmarks were based on(More)
BACKGROUND Anterior communicating artery complex is the most frequent site of intracranial aneurysms in most reported series. Anterior communicating artery aneurysms are the most complex aneurysms of the anterior circulation due to the angioarchitecture and flow dynamics of the ACoA region, frequent anatomical variations, deep interhemispheric location, and(More)
BACKGROUND AND PURPOSE Common variants have been identified using genome-wide association studies which contribute to intracranial aneurysms (IA) susceptibility. However, it is clear that the variants identified to date do not account for the estimated genetic contribution to disease risk. METHODS Initial analysis was performed in a discovery sample of(More)
The growth rate of intracranial meningiomas was studied in 43 patients against a histologic grading based on the degree of anaplasia. The mean time for doubling of the tumor volume was 415 days (138-1045) in grade I (benign), 178 days (34-551) in grade II (atypical), and 205 days (30-472) in grade III (anaplastic). The difference between grade I and the(More)
At operation, 21 meningeal intracranial hemangiopericytomas resembled meningiomas, but differed histologically. They were frequently attached to sinuses, occipitally located, bled profusely at operation, and had a higher risk of recurrence and metastasis. Specific preoperative diagnosis is possible: computed tomography scan showed a meningiomalike tumor,(More)
BACKGROUND Of the MCA aneurysms, those located at the main bifurcation of the MCA (MbifA) are by far the most frequent. The purpose of this article is to review the practical anatomy, preoperative planning, and avoidance of complications in the microsurgical dissection and clipping of MbifAs. METHODS This review, and the whole series on intracranial(More)
BACKGROUND Distal middle cerebral artery aneurysms originate from branches of MCA distal to its main bifurcation or the peripheral branches. Distal middle cerebral artery aneurysms are the least frequently seen among the middle cerebral artery aneurysms. The purpose of this article is to review the practical anatomy, preoperative planning, and avoidance of(More)