29 results on '"Jääskeläinen, Juha"'
Search Results
2. Non-invasive preoperative localization of primary motor cortex in epilepsy surgery by navigated transcranial magnetic stimulation
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Säisänen, Laura, Könönen, Mervi, Julkunen, Petro, Määttä, Sara, Vanninen, Ritva, Immonen, Arto, Jutila, Leena, Kälviäinen, Reetta, Jääskeläinen, Juha E., and Mervaala, Esa
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- 2010
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3. Fabrication and testing of polyimide-based microelectrode arrays for cortical mapping of evoked potentials
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Myllymaa, Sami, Myllymaa, Katja, Korhonen, Hannu, Töyräs, Juha, Jääskeläinen, Juha E., Djupsund, Kaj, Tanila, Heikki, and Lappalainen, Reijo
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- 2009
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4. Clinical implementation of 4-dihydroxyborylphenylalanine synthesised by an asymmetric pathway
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Kulvik, Martti, Vähätalo, Jyrki, Buchar, Evzen, Färkkilä, Markus, Järviluoma, Eija, Jääskeläinen, Juha, Křiž, Otomar, Laakso, Juha, Rasilainen, Merja, Ruokonen, Inkeri, and Kallio, Merja
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- 2003
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5. Undifferentiated sinonasal carcinoma may respond to single-fraction boron neutron capture therapy
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Kouri, Mauri, Kankaanranta, Leena, Seppälä, Tiina, Tervo, Leena, Rasilainen, Merja, Minn, Heikki, Eskola, Olli, Vähätalo, Jyrki, Paetau, Anders, Savolainen, Sauli, Auterinen, Iiro, Jääskeläinen, Juha, and Joensuu, Heikki
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- 2004
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6. Imaging Classification and Treatment of Spontaneous Intracranial Fusiform and Dissecting Aneurysms.
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Rezai Jahromi, Behnam, Jääskeläinen, Juha E., and Niemelä, Mika
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INTRACRANIAL aneurysms , *DISSECTING aneurysms , *NEUROSURGERY , *ENDOVASCULAR surgery , *DISEASE susceptibility , *THERAPEUTICS - Published
- 2017
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7. Rate and Risk Factors for Shunt Revision in Pediatric Patients with Hydrocephalus—A Population-Based Study.
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Tervonen, Joona, Leinonen, Ville, Jääskeläinen, Juha E., Koponen, Susanna, and Huttunen, Terhi J.
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HYDROCEPHALUS , *INTRAVENTRICULAR hemorrhage , *CONGENITAL disorders , *SURGICAL complications , *JUVENILE diseases , *THERAPEUTICS - Abstract
Background Ventriculoperitoneal shunt (VPS) is a common treatment for patients with hydrocephalus (HC). VPS is associated with complications that may lead to shunt revisions. We studied the surgical outcome of pediatric patients with HC in a population-based setting. Methods The medical charts and imaging findings of 80 patients ≤16 years old who required VPS secondary to HC were studied. Results Mean age at time of initial shunt placement was 3.2 years (SD 4.5) and mean follow-up time was 3.3 years (SD 2.9); 57% of patients were male. Half of patients underwent shunt revision with mean time to first revision of 8 months. Patients ≤6 months old had a higher shunt revision rate compared with patients >6 months old ( P < 0.001). The most common causes of HC requiring VPS were tumors (27.5%), congenital defects (22.5%), and intraventricular hemorrhage (19%). Revision rates in the intraventricular hemorrhage and congenital defects groups were 67% ( P = 0.017) and 72% ( P = 0.016) compared with 32% in the tumor group. Programmable valves (56%) were more common than nonprogrammable valves, but there was no significant difference in shunt survival ( P = 0.632). The mean biparietal measurement change between preoperative and postoperative images was +0.9 mm in the no revision group and +6.6 mm in the revision group ( P = 0.003). Conclusions Half of patients with shunts required revision. Age ≤6 months and intraventricular hemorrhage and congenital defects etiologies of HC were associated with increased risk for shunt revision. Most revisions were done during the first year after the initial VPS. [ABSTRACT FROM AUTHOR]
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- 2017
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8. Hyperspectral Imaging in Brain Tumor Surgery—Evidence of Machine Learning-Based Performance.
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Puustinen, Sami, Vrzáková, Hana, Hyttinen, Joni, Rauramaa, Tuomas, Fält, Pauli, Hauta-Kasari, Markku, Bednarik, Roman, Koivisto, Timo, Rantala, Susanna, von und zu Fraunberg, Mikael, Jääskeläinen, Juha E., and Elomaa, Antti-Pekka
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BRAIN tumors , *MACHINE performance , *MEDICAL imaging systems , *BRAIN imaging , *BRAIN surgery ,TUMOR surgery - Abstract
Hyperspectral imaging (HSI) has the potential to enhance surgical tissue detection and diagnostics. Definite utilization of intraoperative HSI guidance demands validated machine learning and public datasets that currently do not exist. Moreover, current imaging conventions are dispersed, and evidence-based paradigms for neurosurgical HSI have not been declared. We presented the rationale and a detailed clinical paradigm for establishing microneurosurgical HSI guidance. In addition, a systematic literature review was conducted to summarize the current indications and performance of neurosurgical HSI systems, with an emphasis on machine learning-based methods. The published data comprised a few case series or case reports aiming to classify tissues during glioma operations. For a multitissue classification problem, the highest overall accuracy of 80% was obtained using deep learning. Our HSI system was capable of intraoperative data acquisition and visualization with minimal disturbance to glioma surgery. In a limited number of publications, neurosurgical HSI has demonstrated unique capabilities in contrast to the established imaging techniques. Multidisciplinary work is required to establish communicable HSI standards and clinical impact. Our HSI paradigm endorses systematic intraoperative HSI data collection, which aims to facilitate the related standards, medical device regulations, and value-based medical imaging systems. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Structure-function relationships in the ezrin family and the effect of tumor-associated point mutations in neurofibromatosis 2 protein
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Turunen, Ossi, Sainio, Markku, Jääskeläinen, Juha, Carpén, Olli, and Vaheri, Antti
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- 1998
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10. Analgesic Use after Aneurysmal Subarachnoid Hemorrhage: A Population-Based Case−Control Study of 1187 Patients.
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Lindlöf, Minna, Lindgren, Antti, Paavola, Juho, Väntti, Nelli, von und zu Fraunberg, Mikael, Koivisto, Timo, Jääskeläinen, Juha E., Kämäräinen, Olli-Pekka, and Huttunen, Jukka
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CEREBRAL vasospasm , *INTRACEREBRAL hematoma , *SUBARACHNOID hemorrhage , *INTRACRANIAL aneurysm ruptures , *CASE-control method , *INTRACRANIAL aneurysms , *MEDICAL care - Abstract
The purpose of this population-based case−control study was to evaluate analgesic use after subarachnoid hemorrhage (SAH) caused by rupture of a saccular intracranial aneurysm (sIA). The study consisted of 1187 patients alive 12 months after an sIA-SAH who were admitted to Kuopio University Hospital (KUH) between 1995 and 2014. Three controls, matched with age, sex, and birthplace, were included for each patient. Data on ruptured sIA cases admitted to KUH from a defined catchment population in Eastern Finland were obtained from the KUH intracranial aneurysm database. Analgesics were classified according to the Anatomical Therapeutic Chemical Classification system. Data on analgesic medication were retrieved from the Finnish national registry of prescribed medicines of the Social Insurance Institution of Finland. Among 1187 patients with sIA-SAH who were alive 12 months after admission, 83 (7.0%) commenced analgesics use within 12 months after the sIA-SAH versus 53 (1.5%) of the 3561 population controls. The results revealed significantly greater initiation rate of analgesic use among patients with sIA-SAH within a year after sIA-SAH as compared with that of matched population controls (odds ratio 5.0; 95% confidence interval 3.5–7.0; P < 0.001). Analgesic use commencement within 12 months of an sIA-SAH was independently associated with the presence of an intracerebral hematoma. Among patients, commencing analgesic use increased 11% when we compared a year before and a year after sIA-SAH. Our results indicate that patients with sIA-SAH had an increased risk for new pain after sIA-SAH as compared with that of matched control population. [ABSTRACT FROM AUTHOR]
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- 2019
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11. Why Does the Health-Related Quality of Life in Idiopathic Normal-Pressure Hydrocephalus Fail to Improve Despite the Favorable Clinical Outcome?
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Junkkari, Antti, Roine, Risto P., Luikku, Antti, Rauramaa, Tuomas, Sintonen, Harri, Nerg, Ossi, Koivisto, Anne M., Häyrinen, Antti, Viinamäki, Heimo, Soininen, Hilkka, Jääskeläinen, Juha E., and Leinonen, Ville
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QUALITY of life , *CEREBROSPINAL fluid shunts , *HYDROCEPHALUS , *LOGISTIC regression analysis , *CEREBROSPINAL fluid - Abstract
Objective Occasionally, a favorable clinical disease-specific outcome does not reflect into improved generic health-related quality of life (HRQoL) in patients with idiopathic normal-pressure hydrocephalus (iNPH) at 1 year after the installation of a cerebrospinal fluid shunt. Our aim was to identify factors causing this discrepancy. Methods The 1-year HRQoL outcomes of 141 patients with iNPH were evaluated with the generic 15D instrument, in which the minimum clinically important change/difference on the 0–1 scale has been estimated to be ±0.015. A 12-point iNPH grading scale (iNPHGS) was used as a clinical disease-specific outcome measure, in which a 1-point decrease is considered to be clinically important. We identified 29 (21%) patients with iNPH from our prospective study whose HRQoL deteriorated or remained the same despite of a favorable iNPHGS outcome. We analyzed this discrepancy using patients' clinical variables and characteristics. Results Multivariate binary logistic regression analysis indicated that a greater (worse) iNPHGS score at baseline (adjusted odds ratio [OR], 1.7; 95% confidence interval [CI] 1.3–2.3; P < 0.001), comorbid chronic pulmonary disease (40% vs. 20%; adjusted OR 17.8; 95% CI 3.6–89.9; P < 0.001), and any comorbid nonmetastatic tumor (62% vs. 17%; adjusted OR 11.5; 95% CI 1.5–85.3; P = 0.017) predicted discrepancy between iNPHGS and 15D outcomes. Conclusions Frail patients suffering from certain pre-existing comorbidities may not experience improvement in generic HRQoL despite of a favorable clinical disease-specific response. Acknowledging the comorbidity burden of the patient may help clinicians and the patients to understand the conflict between patient-reported and clinical outcomes. [ABSTRACT FROM AUTHOR]
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- 2017
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12. Posterior Cerebral Artery Aneurysms: Treatment and Outcome Analysis in 121 Patients.
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Goehre, Felix, Jahromi, Behnam Rezai, Lehecka, Martin, Lehto, Hanna, Kivisaari, Riku, Andrade-Barazarte, Hugo, Ibrahim, Tarik F., Párraga, Richard Gonzalo, Ludtka, Christopher, Meisel, Hans Jörg, Koivisto, Timo, von und zu Fraunberg, Mikael, Niemelä, Mika, Jääskeläinen, Juha E., and Hernesniemi, Juha A.
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ANEURYSMS , *DISEASE incidence , *ARTERIOVENOUS malformation , *MICROSURGERY , *VASCULAR diseases - Abstract
Objective Aneurysms of the posterior cerebral artery (PCA) are uncommon. Because of their low incidence, only 5 series with more than 30 patient cases have been reported. The treatment of PCA aneurysms is challenging because of the high frequency of fusiform aneurysms and closeness to important neuroanatomic structures. Methods A total of 121 patients with 135 PCA aneurysms were reviewed. The clinical and radiologic data, treatment strategies, and 1-year outcomes were analyzed. Patients with giant aneurysms, associated aneurysms, and aneurysms on arteriovenous malformation-feeding PCAs were considered as complex cases. Outcomes were categorized into 3 groups: good (modified Rankin Scale [mRS], score 0–1), moderate (mRS score, 2–4), and poor (mRS score, 5–6). Results There were 52 ruptured (39%) and 83 unruptured (61%) PCA aneurysms in 121 patients, with the following distribution: P1 ( n = 53), P1/2 ( n = 39), P2 ( n = 28), and P3 ( n = 15). The incidence of fusiform PCA aneurysms was high (24%). Microsurgical treatment was applied to 63 aneurysms and endovascular treatment to 19 aneurysms; 55 aneurysms were treated conservatively. The following treatment results were achieved: for patients with unruptured PCA aneurysms, n = 19; 12 good outcomes, 63%; 6 moderate, 31%; 1 poor, 1%; for patients with ruptured PCA aneurysms, n = 27; 10 good, 37%; 9 moderate, 33%; 8 poor, 30%; and for patients with complex neurovascular diseases and PCA aneurysms, n = 96; 42 good, 43%; 40 moderate, 42%; 14 poor, 15%. Conclusions Aneurysms of the PCA are infrequent and often associated with other vascular diseases. Microsurgery and endovascular treatment are effective for the occlusion of PCA aneurysms. The preservation or reconstruction of the parent vessel is crucial for favorable treatment outcomes. [ABSTRACT FROM AUTHOR]
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- 2016
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13. Transient Cardiac Arrest Induced by Adenosine: A Tool for Contralateral Clipping of Internal Carotid Artery-Ophthalmic Segment Aneurysms.
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Andrade-Barazarte, Hugo, Luostarinen, Teemu, Goehre, Felix, Kivelev, Juri, Jahromi, Behnam Rezai, Ludtka, Christopher, Lehto, Hanna, Raj, Rahul, Ibrahim, Tarik F., Niemela, Mika, Jääskeläinen, Juha E., and Hernesniemi, Juha A.
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CARDIAC arrest , *PHYSIOLOGICAL effects of adenosine , *CAROTID artery diseases , *OPHTHALMIC artery , *HEALTH outcome assessment , *ELECTROCARDIOGRAPHY - Abstract
Background The disadvantages of a contralateral approach (CA) include deep and narrow surgical corridors and inconsistent ability to achieve proximal control of the supraclinoid internal carotid artery (ICA). However, a CA remains as a microsurgical option for selected ICA-ophthalmic (opht) segment aneurysms. Objective To describe transient cardiac arrest induced by adenosine as an alternative tool to obtain proximal vascular control and soften the aneurysm sac in selected patients while performing a CA. Methods From January 1998 to December 2013, we retrospectively identified 30 patients with ICA-opht segment aneurysms treated through a CA. Of those, 8 patients received an intravenous bolus of adenosine to induce transient cardiac arrest for softening of the aneurysm sac. We reviewed preoperative clinical status, characteristics of the contralateral aneurysm, adenosine doses, asystole time, recovery of normal circulation, outcome, and complications. Results No preoperative cardiac or pulmonary pathologies were found in the study population. All contralateral ICA-opht segment aneurysms were unruptured, small, and saccular in shape. Transient cardiac arrest was induced because it was impossible to apply a temporary clip on the parent contralateral supraclinoid ICA. The median dose of adenosine was 22.5 mg (range, 5–50 mg) and the asystole time ranged from 20 to 40 seconds. All patients (n = 8) had good postoperative outcomes. No brain infarction or cardiac complications appeared postoperatively. Conclusions In selected patients, transient cardiac arrest induced by adenosine during a contralateral approach allows a brief flow arrest and softening of the aneurysm for safer exposure and clipping. [ABSTRACT FROM AUTHOR]
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- 2015
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14. Biodistribution of boron after intravenous 4-dihydroxyborylphenylalanine-fructose (BPA-F) infusion in meningioma and schwannoma patients: A feasibility study for boron neutron capture therapy.
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Kulvik, Martti, Kallio, Merja, Laakso, Juha, Vähätalo, Jyrki, Hermans, Raine, Järviluoma, Eija, Paetau, Anders, Rasilainen, Merja, Ruokonen, Inkeri, Seppälä, Matti, and Jääskeläinen, Juha
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BORON-neutron capture therapy , *INTRAVENOUS therapy , *MENINGIOMA , *SCHWANNOMAS , *FEASIBILITY studies , *PATIENTS , *THERAPEUTICS - Abstract
We studied the uptake of boron after 100 mg/kg BPA infusion in three meningioma and five schwannoma patients as a pre-BNCT feasibility study. With average tumour-to-whole blood boron concentrations of 2.5, we discuss why BNCT could, and probably should, be developed to treat severe forms of the studied tumours. However, analysing 72 tumour and 250 blood samples yielded another finding: the plasma-to-whole blood boron concentrations varied with time, suggesting that the assumed constant boron ratio of 1:1 between normal brain tissue and whole blood deserves re-assessment. [ABSTRACT FROM AUTHOR]
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- 2015
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15. Subtemporal Approach to Posterior Cerebral Artery Aneurysms.
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Goehre, Felix, Lehecka, Martin, Jahromi, Behnam Rezai, Lehto, Hanna, Kivisaari, Riku, Hijazy, Ferzat, Nayeb, Lamia, Sugimoto, Tetsuaki, Morishige, Masaki, Elsharkawy, Ahmed, von und zu Fraunberg, Mikael, Jääskeläinen, Juha E., and Hernesniemi, Juha A.
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INTRACRANIAL aneurysms , *CEREBRAL arterial diseases , *POSTERIOR cerebral artery , *SUBARACHNOID hemorrhage , *MICROSURGERY - Abstract
Objective Aneurysms of the posterior cerebral artery (PCA) are rare, and therefore the individual and institutional experience of their microsurgical management is usually limited. In the present article, we describe our experience with the subtemporal approach to aneurysms arising from the PCA. Methods We reviewed 34 patients diagnosed with 37 PCA aneurysms, all microsurgically managed using the subtemporal approach between 1980 and 2012 at 2 Finnish neurosurgical centers (Helsinki and Kuopio). The following procedures were applied using the subtemporal approach: neck clipping (n = 24); proximal occlusion (n = 7); trapping (n = 2); wrapping (n = 1); aneurysmoraphy (n = 1); bypass bridging/trapping (n = 1); and a complex excimer laser-assisted nonocclusive anastomosis procedure (n = 1). Results Of these 34 patients, 16 presented with acute subarachnoid hemorrhage as a result of PCA aneurysm rupture, and 11 of the 16 had good outcome (modified Rankin scale 0–2) at 3 months The remaining 18 patients were treated microsurgically for incidentally diagnosed unruptured aneurysms, and 14 of the 18 had a good outcome. The most common serious complication in this series was an ipsilateral PCA infarction (12/34; 35%), mostly after proximal occlusion (n = 7) and/or trapping (n = 2). Conclusions The subtemporal approach is a suitable approach to aneurysms of the segments P1, P1–P2 junction, and P2, as well as the anterior P3 segment of the PCA. Using the subtemporal approach, the cerebrospinal fluid is released before retraction is necessary to prevent temporal lobe injury. The subtemporal approach can provide enough space for revascularization procedures. The most encountered complications were not related to the subtemporal approach but to the specific nature of PCA aneurysms. [ABSTRACT FROM AUTHOR]
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- 2015
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16. Microneurosurgical management of aneurysms at A4 and A5 segments and distal cortical branches of anterior cerebral artery
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Lehecka, Martin, Dashti, Reza, Hernesniemi, Juha, Niemelä, Mika, Koivisto, Timo, Ronkainen, Antti, Rinne, Jaakko, and Jääskeläinen, Juha
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CEREBRAL arteries , *VASCULAR diseases , *TOMOGRAPHY , *INTRACRANIAL aneurysms ,ANEURYSM treatment - Abstract
Abstract: Background: Aneurysms originating distal to the A3 segment of the ACA, located on the A4 and the A5 segments or the distal cortical branches of the ACA (AdistAs) are rare, forming about 0.5% of all IAs. There are only few reports on management of AdistAs. In this article, we review the practical anatomy, preoperative planning, and avoidance of complications in the microsurgical dissection and clipping of AdistAs. Methods: This review, and the whole series on IAs, is mainly based on the personal microneurosurgical experience of the senior author (J. H.) in 2 Finnish centers (Helsinki and Kuopio), which serve without patient selection the catchment area in Southern and Eastern Finland. Results: These 2 centers have treated more than 10000 patients with IAs since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients and 4253 IAs, there were 26 patients carrying 26 AdistAs, forming 0.9% of all patients with IAs, 0.6% of all IAs, and 2% of all ACA aneurysms. A total of 10 (38%) patients presented with ruptured AdistAs, with ICH in 4 (40%) and IVH in 2 (20%); 16 patients (62%) had multiple aneurysms. Conclusions: AdistAs are small, even when ruptured, with relatively wide base, and they are frequently associated with ICHs. Our data suggest that AdistAs rupture at smaller size than IAs in general. The challenge is to locate the aneurysm inside the interhemispheric fissure and to clip the neck adequately without obstructing branching arteries at the base. Unruptured AdistAs also need microneurosurgical clipping even when they are small. [Copyright &y& Elsevier]
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- 2008
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17. Microneurosurgical management of aneurysms at the A2 segment of anterior cerebral artery (proximal pericallosal artery) and its frontobasal branches
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Lehecka, Martin, Dashti, Reza, Hernesniemi, Juha, Niemelä, Mika, Koivisto, Timo, Ronkainen, Antti, Rinne, Jaakko, and Jääskeläinen, Juha
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ANEURYSMS , *CEREBRAL arterial diseases , *SUBARACHNOID hemorrhage , *CEREBROSPINAL fluid - Abstract
Abstract: Background: Aneurysms originating from the A2 segment of ACA and its frontobasal branches are rare, forming less than 1% of all IAs. There are only few reports on management of A2As. In this article, we review the practical anatomy, preoperative planning, and avoidance of complications in the microsurgical dissection and clipping of A2As. Methods: This review, and the whole series on IAs, is mainly based on the personal microneurosurgical experience of the senior author (JH) in two Finnish centers (Helsinki and Kuopio), which serve, without patient selection, the catchment area in Southern and Eastern Finland. Results: These two centers have treated more than 10000 patients with IAs since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients and 4253 IAs, there were 35 patients carrying 35 A2As, forming 1% of all patients with IAs, 0.8% of all IAs, and 3% of all ACA aneurysms. Twenty-one (60%) patients presented with ruptured A2As with ICH in 11 (52%) and IVH in 7 (33%). Nineteen patients (54%) had multiple aneurysms. Conclusions: A2As are often small, even when ruptured, with relatively wide base, and they are frequently associated with ICHs of IVHs. Our data suggest that A2As rupture at smaller size than IAs in general. The challenge is to select appropriate approach, locate the aneurysm deep inside the interhemispheric fissure, and to clip the neck adequately without obstructing branching arteries at the base. Unruptured A2As also need microneurosurgical clipping even when they are small. [Copyright &y& Elsevier]
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- 2008
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18. Microneurosurgical management of aneurysms at A3 segment of anterior cerebral artery
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Lehecka, Martin, Dashti, Reza, Hernesniemi, Juha, Niemelä, Mika, Koivisto, Timo, Ronkainen, Antti, Rinne, Jaakko, and Jääskeläinen, Juha
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BLOOD vessels , *ARTERIES , *CEREBROSPINAL fluid , *HEMORRHAGE - Abstract
Abstract: Background: Aneurysms originating from the A3 segment of anterior cerebral artery (A3A) form about 5% of all IAs. They are the most common among distal anterior cerebral artery aneurysms. There are relatively few reports on management of A3As. In this article, we review the practical anatomy, preoperative planning, and avoidance of complications in the microsurgical dissection and clipping of A3As. Methods: This review, and the whole series on IAs, is mainly based on the personal microneurosurgical experience of the senior author (JH) in 2 Finnish centers (Helsinki and Kuopio), which serve, without patient selection, the catchment area in Southern and Eastern Finland. Results: These 2 centers have treated more than 10000 patients with IAs since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients and 4253 IAs, there were 163 patients carrying 174 A3As, forming 5% of all patients with IAs, 4% of all IAs, and 15% of all ACA aneurysms. Ninety-seven (60%) patients presented with ruptured A3As with ICH in 27 (28%) and IVH in 26 (27%). Ninety-four (58%) patients had multiple aneurysms. Conclusions: Aneurysms of A3 segment of ACA are often small, even when ruptured, with relatively wide base, and they are frequently associated with ICHs of IVHs. Our data suggest that A3As rupture at smaller size than IAs in general. The challenge is to select appropriate approach, to locate the aneurysm deep inside the interhemispheric fissure, and to clip the neck adequately without obstructing branching arteries at the base. Unruptured A3As also need microneurosurgical clipping even when they are small. [Copyright &y& Elsevier]
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- 2008
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19. Microneurosurgical management of anterior communicating artery aneurysms
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Hernesniemi, Juha, Dashti, Reza, Lehecka, Martin, Niemelä, Mika, Rinne, Jaakko, Lehto, Hanna, Ronkainen, Antti, Koivisto, Timo, and Jääskeläinen, Juha E.
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ANEURYSMS , *MICROSURGERY , *CEREBROSPINAL fluid , *TOMOGRAPHY - Abstract
Abstract: 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 danger of severing the perforators with ensuing neurologic deficits. The authors review the practical microsurgical anatomy, importance of preoperative imaging in surgical planning, and microneurosurgical steps in dissection and clipping of ACoAAs. Methods: This review, and the whole series on intracranial aneurysms, are mainly based on the personal microneurosurgical experience of the senior author (JH) in 2 Finnish centers (Helsinki and Kuopio), which serve, without patient selection, the catchment area in Southern and Eastern Finland. Results: These 2 centers have treated more than 10000 patients with aneurysm since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients with 4253 aneurysms, 1145 patients (38%) had altogether 1179 ACA aneurysms; of them, 898 patients harbored 921 (78%) ACoAAs. In this series, 715 patients (80%) presented with ruptured ACoAAs with the median diameter of 7 mm. Giant ACoAAs were present in 15 (2%), whereas only 3 (0.3%) were classified as fusiform. Conclusions: Anterior communicating artery aneurysms present frequently with SAH at small size. Furthermore, unruptured ACoAAs may have increased risk of rupture regardless of size, also as an associated aneurysm, and require treatment. The aim in microneurosurgical management of an ACoAA is total occlusion of the aneurysm sac with preservation of flow in all branching and perforating arteries. This demanding task necessitates perfect surgical strategy based on review of the 3D angioarchitecture and abnormalities of the patient''s ACoA complex with its ACoAA and to orientate accordingly during the microsurgical dissection. The surgical trajectory should provide optimal visualization of the ACoA complex without massive brain retraction. Precise dissection in the 3D anatomy of the ACoA complex and perforators requires not only experience and skill but patience to work the dome and base under repeated protection of temporary clips and pilot clips. This is particularly important with the complex, large, and giant aneurysms. [Copyright &y& Elsevier]
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- 2008
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20. Microneurosurgical management of proximal anterior cerebral artery aneurysms
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Dashti, Reza, Hernesniemi, Juha, Lehto, Hanna, Niemelä, Mika, Lehecka, Martin, Rinne, Jaakko, Porras, Matti, Ronkainen, Antti, Phornsuwannapha, Surachest, Koivisto, Timo, and Jääskeläinen, Juha E.
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ANEURYSMS , *VASCULAR diseases , *AORTIC aneurysms , *INTRACRANIAL aneurysms - Abstract
Abstract: Background: Aneurysms originating from the proximal segment of anterior cerebral artery (A1As) are rare, forming less than 1% of all IAs. There are only few reports on microneurosurgical management of A1As. In this article, the authors review the practical anatomy, preoperative planning, and avoidance of complications in the microsurgical dissection and clipping of A1As. Methods: This review, and the whole series on IAs, is mainly based on the personal microneurosurgical experience of the senior author (JH) in 2 Finnish centers (Helsinki and Kuopio), which serve without patient selection the catchment area in Southern and Eastern Finland. Results: These 2 centers have treated more than 10000 patients with aneurysm since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients with 4253 aneurysms, there were 23 patients carrying 23 A1As, forming 0.8% of all patients with aneurysm, 0.5% of all aneurysms, and 2% of all ACA aneurysms. Twelve (52%) patients presented with ruptured A1As with ICH in 3 (25%) and IVH in 2 (17%). Seventy percent of patients had at least 1 associated aneurysm. Conclusions: Aneurysms arising from A1 are usually small, with a fragile wall. Our data suggest that A1As rupture at smaller size than IAs in general. Because of their small size and involvement of perforating arteries at their base, microneurosurgical clipping is the method of choice in treatment of ruptured A1As. Unruptured A1As also need microneurosurgical clipping even when they are small. [Copyright &y& Elsevier]
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- 2007
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21. Microneurosurgical management of distal middle cerebral artery aneurysms
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Dashti, Reza, Hernesniemi, Juha, Niemelä, Mika, Rinne, Jaakko, Lehecka, Martin, Shen, Hu, Lehto, Hanna, Albayrak, Baki S., Ronkainen, Antti, Koivisto, Timo, and Jääskeläinen, Juha E.
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ANEURYSMS , *VASCULAR diseases , *ARTERIES , *INTRACRANIAL aneurysms - Abstract
Abstract: 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 complications in the microsurgical dissection and clipping of MdistAs. Methods: This review, and the whole series on intracranial aneurysms, are mainly based on the personal microneurosurgical experience of the senior author (JH) in 2 Finnish centers (Helsinki and Kuopio), which serve without patient selection the catchment area in Southern and Eastern Finland. Results: These 2 centers have treated more than 10000 aneurysm patients since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients with 4253 aneurysms, 69 patients carrying altogether 78 MdistAs formed 5% of all MCA aneurysms. Among the 18 patients with ruptured MdistAs (23%), an ICH occurred in 9 (50%). Conclusions: Distal middle cerebral artery aneurysms are rare. The microneurosurgical treatment of MdistAs is challenging. They are often difficult to localize during the operation, and lack of collateral circulation makes their occlusion more demanding. High rate of ICH and high tendency of rebleeding urge acute or emergency surgery in most of ruptured cases. Microneurosurgical clipping is the most effective treatment of MdistAs. [Copyright &y& Elsevier]
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- 2007
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22. Microneurosurgical management of middle cerebral artery bifurcation aneurysms
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Dashti, Reza, Hernesniemi, Juha, Niemelä, Mika, Rinne, Jaakko, Porras, Matti, Lehecka, Martin, Shen, Hu, Albayrak, Baki S., Lehto, Hanna, Koroknay-Pál, Päivi, de Oliveira, Rafael Sillero, Perra, Giancarlo, Ronkainen, Antti, Koivisto, Timo, and Jääskeläinen, Juha E.
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ANEURYSMS , *BRAIN blood-vessels , *ANGIOGRAPHY , *SURGERY , *CEREBROVASCULAR disease - Abstract
Abstract: 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 aneurysms, is mainly based on the personal microneurosurgical experience of the senior author (JH) in 2 Finnish centers (Helsinki and Kuopio), which serve without patient selection the catchment area in southern and eastern Finland. Results: These 2 centers have treated more than 10000 patients with intracranial aneurysm''s since 1951. In the Kuopio Cerebral Aneurysm Data Base of 3005 patients with 4253 aneurysms, MbifAs formed 30% of all ruptured aneurysms, 36% of all unruptured aneurysms, 35% of all giant aneurysms, and 89% of all MCA aneurysms. Importantly, in 45%, rupture of MbifA caused an ICH. Conclusions: Middle cerebral artery bifurcation aneurysms are often broad necked and may involve one or both branches of the bifurcation (M2s). The anatomical and hemodynamic features of MbifAs make them usually more favorable for microneurosurgical treatment. In population-based services, MbifAs are frequent targets of elective surgery (unruptured), acute surgery (ruptured), and emergency surgery (large ICH), even advanced approaches (giant). The challenge is to clip the neck adequately, without neck remnants, while preserving the bifurcational flow. [Copyright &y& Elsevier]
- Published
- 2007
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23. Association of Fatal Aneurysmal Subarachnoid Hemorrhage with Human Leukocyte Antigens in the Finnish Population
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Frösen, Juhana, Pitkäniemi, Janne, Tulamo, Riikka, Marjamaa, Johan, Isoniemi, Helena, Niemelä, Mika, Jääskeläinen, Juha, Lokki, Marja-Liisa, and Matinlauri, Irma
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HLA histocompatibility antigens , *ANTIGENS , *IMMUNOGLOBULINS , *BONE marrow - Abstract
Abstract: Human leukocyte antigens (HLA) have been reported to associate with the risk of aneurysmal subarachnoid hemorrhage (SAH) and poor outcome after SAH. Our aim was to identify HLA antigens that associate with the risk of fatal SAH in the Finnish population. Medical records of 600 cadaveric organ donors were reviewed to find organ donors that succumbed to SAH (n = 232) or brain trauma (n = 151). HLA antigen frequencies in these groups were compared with HLA frequenciens in a reference population of 10,000 bone marrow donors. Chi-Square test with Bonferroni correction and multiplicative logistic regression models were used and false positive result probabilities (FPRP) were calculated. Alpha-level was 0.01. HLA-A3 associated with fatal SAH (p = 0.0014, OR 1.3 and 95%CI 1.1–1.6) and HLA-DR7 inversely associated with fatal SAH (p = 0.0040, OR 0.3 and 95%CI 0.2–0.6). HLA-A3 but not HLA-DR7 showed also a positive trend in donors with brain trauma. FPRP was below 0.5 for HLA-A3, but clearly above 0.5 for HLA-DR7. HLA-A3 seems to associate with fatal SAH in the Finnish population. Further studies are needed to reveal the pathobiologic mechanisms for how HLA-A3 associates with the risk of fatal SAH in Finns. [Copyright &y& Elsevier]
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- 2007
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24. Microneurosurgical management of proximal middle cerebral artery aneurysms
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Dashti, Reza, Rinne, Jaakko, Hernesniemi, Juha, Niemelä, Mika, Kivipelto, Leena, Lehecka, Martin, Karatas, Ayse, Avci, Emel, Ishii, Keisuke, Shen, Hu, Peláez, José G., Albayrak, Baki S., Ronkainen, Antti, Koivisto, Timo, and Jääskeläinen, Juha E.
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MICROSURGERY , *INTRACRANIAL aneurysms , *CEREBRAL arteries , *NEUROSURGERY - Abstract
Abstract: Background: The M1As are located in the main trunk (M1) of the MCA, between the bifurcation of the ICA and the main bifurcation of M1. Proximal MCA aneurysms are often small and thin-walled, which makes their proper clipping tedious. There are few reports on their microsurgery. Methods: This review, and the whole series on intracranial aneurysms, is mainly based on the personal microneurosurgical experience of the senior author (JH) in 2 Finnish centers (Helsinki and Kuopio), which serve, without selection, the catchment area in the southern and eastern Finland. Results: These 2 centers have treated more than 10000 patients with aneurysm since 1953. We review the practical anatomy, preoperative planning, and avoidance of complications in the microsurgical dissection and clipping of M1As which form 7.4% of all intracranial and 14% of all MCA aneurysms in our patients. Conclusions: Proximal MCA aneurysms are often wide-necked and intimately connected to an M1 branch at its origin on M1, features that favor exosurgery rather than endosurgery. The direction and course of the parent and branching arteries and the orientation of the fundus are the most important factors affecting the efficacy and safety of clipping. [Copyright &y& Elsevier]
- Published
- 2007
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25. Water dissection technique of Toth for opening neurosurgical cleavage planes
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Nagy, Laszlo, Ishii, Keisuke, Karatas, Ayse, Shen, Hu, Vajda, Janos, Niemelä, Mika, Jääskeläinen, Juha, Hernesniemi, Juha, and Toth, Szabolcs
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NEUROSURGERY , *MENINGIOMA , *BRAIN blood-vessels , *MEDICAL microscopy - Abstract
Abstract: Background: The low-pressure water dissection technique of Toth, first reported in 1987, is a method to cautiously open neurosurgical cleavage planes such as the sylvian fissure or the interhemispheric space, and the interfaces between extraparenchymal masses and the adjacent brain. The aim of this technical report is to present our long-term experience with this simple and elegant asset of microneurosurgery and to promote its widespread use. Method: Water is injected under microscopic control by a handheld syringe with a blunt needle or by an irrigating balloon applying repeated injections of physiological saline into the cleavage plane to open it. Findings and Conclusion: The water dissection technique of Toth has been extensively used in Budapest and Helsinki in thousands of microsurgical cases, in removal of meningiomas and to open sylvian and interhemispheric fissure. In our experience, there have been no noticeable complications, and we recommend this technique for widespread use. It is a very inexpensive, simple, and effective method not requiring any expensive or complicated devices. [Copyright &y& Elsevier]
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- 2006
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26. Some collected principles of microneurosurgery: simple and fast, while preserving normal anatomy: A review
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Hernesniemi, Juha, Niemelä, Mika, Karatas, Ayse, Kivipelto, Leena, Ishii, Keisuke, Rinne, Jaakko, Ronkainen, Antti, Koivisto, Timo, Kivisaari, Riku, Shen, Hu, Lehecka, Martin, Frösen, Juhana, Piippo, Anna, and Jääskeläinen, Juha E.
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NEUROSURGERY , *CENTRAL nervous system , *NEUROLOGY , *MICROSCOPES - Abstract
Abstract: Microneurosurgical techniques introduced by Prof Yasargil in the 1960s have increased the neurosurgeon''s ability to operate in small and often very narrow and deep gaps. Microneurosurgical techniques—ensuring an almost bloodless field and mostly obviating need for transfusion—should be atraumatic and noninvasive to the already lesioned central nervous system tissues and structures. Instruments in microneurosurgery range from very short to very long and from sturdy to delicate, depending on the working depth, characteristics of tissues, and the microneurosurgical anatomy. However, to keep it simple and fast, and to appreciate normal anatomy, it is preferable to use only a limited array of instruments. Besides the use of instruments and the operating microscope, everything else in the neurosurgical arena should be optimized and professional, such as the positioning of the patient and the conduct of neuroanesthesia. This review of the very basics is distilled from the Helsinki and Kuopio neurosurgery practices in Finland and from the senior author''s (JH) experience of close to 10000 operations, and this is to encourage young neurosurgeons of the world—most of them working with limited resources—to continue to improve their microneurosurgical skills to serve their patients best. [Copyright &y& Elsevier]
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- 2005
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27. Recurrent DNA sequence copy losses on chromosomal arm 6q in capillary hemangioblastoma
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Lemeta, Sebsebe, Aalto, Yan, Niemelä, Mika, Jääskeläinen, Juha, Sainio, Markku, Kere, Juha, Knuutila, Sakari, and Böhling, Tom
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CHROMOSOME abnormalities , *COMPARATIVE genomic hybridization , *NUCLEOTIDE sequence ,CENTRAL nervous system tumors - Abstract
Capillary hemangioblastomas (CHB) of the central nervous system, the most common tumor in von Hippel-Lindau (VHL) disease, usually show mutations in the VHL tumor suppressor gene on chromosome 3p25∼p26. Because little is known concerning the cytogenetic changes in these tumors, we studied 22 cases through comparative genomic hybridization to screen for DNA copy number changes in both sporadic and VHL-associated CHB. Our analysis revealed that 6 of 22 samples (27%) contained DNA copy number losses, whereas no gains were observed. The most recurrent finding was loss of chromosomal arm 6q, seen in five cases. In two of these cases also loss of chromosome 3 was noted. The third aberration observed was loss of chromosome 8, seen in one case. No differences were noted between VHL-associated and sporadic tumors, nor did the cytogenetic aberrations correlate with the clinical outcome. The loss of 6q, seen in this study and previously in other VHL-associated tumors (renal cell carcinomas and pheochromocytomas) and other tumors, suggest that this chromosome area may contain tumor suppressor genes involved in the early steps of tumorigenesis. [Copyright &y& Elsevier]
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- 2002
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28. Incidence, Comorbidities, and Mortality in Idiopathic Normal Pressure Hydrocephalus.
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Pyykkö, Okko T., Nerg, Ossi, Niskasaari, Hanna-Mari, Niskasaari, Timo, Koivisto, Anne M., Hiltunen, Mikko, Pihlajamäki, Jussi, Rauramaa, Tuomas, Kojoukhova, Maria, Alafuzoff, Irina, Soininen, Hilkka, Jääskeläinen, Juha E., and Leinonen, Ville
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HYDROCEPHALUS , *SURVIVAL behavior (Humans) , *PATIENTS ,CAUSE of death statistics - Abstract
Object To investigate the incidence, comorbidities, mortality, and causes of death in idiopathic normal pressure hydrocephalus (iNPH). Methods A cohort of 536 patients with possible NPH from a defined population with a median follow-up time of 5.1 years, (range 0.04–19.9 years) was included in the study. Patients were evaluated by brain imaging and intraventricular pressure monitoring, with a brain biopsy specimen immunostained against amyloid-β and hyperphosphorylated τ. Hospital records were reviewed for vascular diseases and type 2 diabetes mellitus (T2DM). Death certificates and yearly population of the catchment area were obtained from national registries. Results A total of 283 patients had a clinical diagnosis of iNPH, leading to a median annual incidence of 1.58 iNPH patients per 100,000 inhabitants (range, 0.8–4.5). Alzeimer disease–related brain biopsy findings were less frequent in iNPH patients than in non-iNPH patients ( P < 0.05). An overrepresentation of hypertension (52% vs. 33%, P < 0.001) and T2DM (23% vs. 13%, P = 0.002) was noted in iNPH patients. Age (hazard ratio [HR] 1.04/year, 95% confidence interval [CI] 1.03–1.06, P < 0.001) and T2DM (HR 1.63, 95% CI 1.23–2.16, P < 0.001) increased the risk of death in the iNPH patients and in the total population. iNPH was associated with decreased risk of death (HR 0.63, 95% CI 0.50–0.78, P < 0.001). The most frequent causes of death were cardiovascular and cerebrovascular disease. Dementia as a cause of death was more common in non-iNPH patients (27% vs. 10%, P < 0.001). Conclusions Hypertension and T2DM are common in iNPH and the latter causes excess mortality in the affected patients. [ABSTRACT FROM AUTHOR]
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- 2018
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29. Transcriptomics and mechanistic elucidation of Alzheimer's disease risk genes in the brain and in vitro models.
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Martiskainen, Henna, Viswanathan, Jayashree, Nykänen, Niko-Petteri, Kurki, Mitja, Helisalmi, Seppo, Natunen, Teemu, Sarajärvi, Timo, Kurkinen, Kaisa M.A., Pursiheimo, Juha-Pekka, Rauramaa, Tuomas, Alafuzoff, Irina, Jääskeläinen, Juha E., Leinonen, Ville, Soininen, Hilkka, Haapasalo, Annakaisa, Huttunen, Henri J., and Hiltunen, Mikko
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GENETIC transcription , *ALZHEIMER'S disease risk factors , *ALZHEIMER'S patients , *IN vitro studies , *GENE expression , *GENETIC engineering , *EXONS (Genetics) , *ALLELES - Abstract
In this study, we have assessed the expression and splicing status of genes involved in the pathogenesis or affecting the risk of Alzheimer's disease (AD) in the postmortem inferior temporal cortex samples obtained from 60 subjects with varying degree of AD-related neurofibrillary pathology. These subjects were grouped based on neurofibrillary pathology into 3 groups: Braak stages 0-II, Braak stages III-IV, and Braak stages V-VI. We also examined the right frontal cortical biopsies obtained during life from 22 patients with idiopathic shunt-responding normal pressure hydrocephalus, a disease that displays similar pathologic alterations as seen in AD. These 22 patients were categorized according to dichotomized amyloid-β positive or negative pathology in the biopsies. We observed that the expression of FRMD4A significantly decreased, and the expression of MS4A6A significantly increased in relation to increasing AD-related neurofibrillary pathology. Moreover, the expression of 2 exons in both CLU and TREM2 significantly increased with increase in AD-related neurofibrillary pathology. However, a similar trend toward increased expression in CLU and TREM2 was observed with most of the studied exons, suggesting a global change in the expression rather than altered splicing. Correlation of gene expression with well-established AD-related factors, such as α-, β-, and γ-secretase activities, brain amyloid-β42 levels, and cerebrospinal fluid biomarkers, revealed a positive correlation between β-secretase activity and the expression of TREM2 and BIN1 . In expression quantitative trait loci analysis, we did not detect significant effects of the risk alleles on gene expression or splicing. Analysis of the normal pressure hydrocephalus biopsies revealed no differences in the expression or splicing profiles of the studied genes between amyloid-β positive and negative patients. Using the protein-protein interaction-based in vitro pathway analysis tools, we found that downregulation of FRMD4A associated with increased APP-β-secretase interaction, increased amyloid-β40 secretion, and altered phosphorylation of tau. Taken together, our results suggest that the expression of FRMD4A , MS4A6A , CLU , and TREM2 is altered in relation to increasing AD-related neurofibrillary pathology, and that FRMD4A may play a role in amyloidogenic and tau-related pathways in AD. Therefore, investigation of gene expression changes in the brain and effects of the identified genes on disease-associated pathways in vitro may provide mechanistic insights on how alterations in these genes may contribute to AD pathogenesis. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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