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Dive into the research topics where Juhani Pyhtinen is active.

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Featured researches published by Juhani Pyhtinen.


Journal of Trauma-injury Infection and Critical Care | 2004

Effects of Head and Extracranial Injuries on Serum Protein S100b Levels in Trauma Patients

Olli Savola; Juhani Pyhtinen; Tuomo K. Leino; Simo Siitonen; Onni Niemelä; Matti Hillbom

BACKGROUND Serum protein S100B determinations have been recently suggested as markers of traumatic brain injury. However, little is known about the effects of extracranial injuries on S100B levels in trauma patients. METHODS We studied 224 patients with head trauma (54 of whom also had extracranial injuries), 155 patients with various types of extracranial injuries, and 8 healthy pilots exposed to high Gz forces. The head trauma patients had either no brain injury (n = 35), mild brain injury (n = 165), or moderate to severe brain injury (n = 24). The extracranial injuries were divided into small and large injuries. Serum protein S100B levels were determined from samples taken within 6 hours after the trauma event. RESULTS The head trauma patients had a significantly higher median S100B (0.17 microg/L) than the patients with extracranial injuries (0.07 microg/L) (p < 0.001). Serum S100B levels also correlated with the severity of brain injury (p < 0.001), the highest values occurring in the patients with moderate to severe brain injury (1.27 microg/L). However, large extracranial injuries also elevated S100B levels (0.35 microg/L), whereas small extracranial injuries in the absence of head trauma did not significantly affect S100B levels (0.07 microg/L). Above the cutoff level of 0.13 microg/L, there were 61% of the head trauma patients and 26% of those with extracranial injuries (Pearson chi test, p < 0.001). However, only 4% of the patients with purely extracranial injuries had a concentration of S100B above the cutoff level of 0.50 microg/L, whereas the head trauma patients with moderate to severe brain injury exceeded this cutoff in 67% of the cases. Exposure to high Gz forces did not influence serum S100B levels in healthy individuals. CONCLUSION We conclude that serum S100B is a sensitive marker of brain injury, which correlates with the severity of the injury. Large extracranial injuries also elevate S100B levels. However, S100B has a high negative predictive power, and the finding of a normal S100B value shortly after trauma should thus exclude significant brain injury with a high accuracy.


Stroke | 2006

Regular Aspirin-Use Preceding the Onset of Primary Intracerebral Hemorrhage is an Independent Predictor for Death

Pertti Saloheimo; Mikko Ahonen; Seppo Juvela; Juhani Pyhtinen; Eeva-Riitta Savolainen; Matti Hillbom

Background and Purpose— Hematoma volume and impaired level of consciousness are the most potent predictors of outcome after spontaneous intracerebral hemorrhage (ICH). The effect of preceding aspirin-use on outcome after ICH is poorly investigated. We investigated short-term mortality and hematoma enlargement in subjects with ICH to find the predictors for these outcomes. Methods— This population-based study included all subjects with ICH during a period of 33 months in the population of Northern Ostrobothnia, Finland. The subjects were identified, and their clinical characteristics and outcomes were checked from hospital records or death records. Results— Three-month mortality of the 208 identified subjects with ICH was 33%. The independent risk factors for death were regular aspirin-use at the onset of ICH (relative risks [RR], 2.5; 95% CI, 1.3 to 4.6; P=0.004), warfarin-use at the onset of ICH (RR, 3.2; 95% CI, 1.6 to 6.1; P=0.001), and ICH score higher than 2 on admission (RR, 13.8; 95% CI, 6.0 to 31.4; P<0.001). Regular aspirin-use preceding the onset of ICH associated significantly with hematoma enlargement during the first week after ICH (P=0.006). Conclusions— We observed poor short-term outcomes and increased mortality, probably attributable to rapid enlargement of hematomas, in the subjects with ICH who had been taking regularly moderate doses of aspirin (median 250 mg) immediately before the onset of the stroke.


Pediatrics | 1998

Psychological findings in preterm children related to neurologic status and magnetic resonance imaging.

Päivi Olsén; Leena Vainionpää; Eija Pääkkö; Marit Korkman; Juhani Pyhtinen; Marjo-Riitta Järvelin

Objective. Preterm children experience learning disabilities more often than full-term children, but detailed information on their neuropsychological and neurologic determinants is lacking. We therefore examined these problems more closely and also studied if clinical neurologic examination and/or magnetic resonance imaging (MRI) can be used as tools to screen the preterm children at risk for these problems. Methods. In a population-based study, the psychological performance of 42 preterm children with a birth weight <1750 g and of their matched controls was assessed at 8 years of age and the findings were then related to clinical neurologic examination and MRI. Learning disabilities of these children, reported by the teachers, were also studied. Results. The cognitive ability of the preterm children, although in the normal range, was significantly lower than that of the control children. They performed particularly poorly in tasks requiring spatial and visuoperceptual abilities, which were associated with the finding of periventricular leukomalacia in MRI, especially with posterior ventricular enlargement. The preterm children with minor neurodevelopmental dysfunction (MND) had the most problems in neuropsychological tests, whereas the clinically healthy preterm children and those with cerebral palsy had fewer problems. The problems of MND children emerged in the domain of attention. They also experienced the most problems at school. Conclusions. Visuospatial problems were associated with periventricular leukomalacia in MRI, but learning disabilities were most frequent among the preterm children with minor neurologic abnormalities. We recommend closer follow-up of preterm children with MND.


Molecular Psychiatry | 1999

Dopamine transporters increase in human brain after alcohol withdrawal.

T P J Laine; A Ahonen; P Torniainen; J Heikkilä; Juhani Pyhtinen; P Räsänen; O Niemelä; M Hillbom

Dopaminergic transmission has been suggested to be a main mechanism mediating reinforcement, withdrawal and craving associated with alcohol addiction. We measured here striatal dopamine (DA) transporter binding from 27 alcoholics within 4 days after cessation of prolonged heavy drinking and after a 4-week period of abstinence with single photon emission computed tomography (SPECT) using a cocaine analogue, iodine-123-β-CIT. Controls were 29 healthy volunteers. Blind quantitative analyses of the SPECT data revealed markedly lower DA transporter binding in alcoholics on admission for detoxification than in the non-alcoholic controls. After a 4-week period of abstinence DA transporter binding increased significantly in the alcoholics (P < 0.0001) reaching the levels of the healthy controls. the most substantial recovery in da transporter binding occurred during the first 4 days of abstinence. the data indicate that prolonged heavy drinking decreases da transporter binding and distrubs synaptic dopamine transport. this may sensitize alcoholics to dopaminergic transmission, which may lead to early relapse after ethanol withdrawal.


Medical and Pediatric Oncology | 2000

White matter changes on MRI during treatment in children with acute lymphoblastic leukemia: Correlation with neuropsychological findings

Eija Pääkkö; Arja Harila‐Saari; Leena Vanionpää; Sinikka Himanen; Juhani Pyhtinen; Marjatta Lanning

BACKGROUND Treatment of childhood acute lymphoblastic leukemia (ALL) may cause structural and functional brain damage. To find out the incidence of white matter changes during therapy, a prospective MRI study was designed, and the findings were correlated with neuropsychological evaluation. PROCEDURE Thirty-three children with ALL underwent serial cranial MRI before, during, and after therapy. Twenty-eight of these children underwent also neuropsychological assessment at the end of treatment. They all received intravenous and intrathecal methotrexate for central nervous system (CNS) therapy, 15 patients received cranial irradiation in addition. RESULTS Transient high-intensity white matter changes were observed by MRI in three children 9% (95% CI, 2-24%) who received chemotherapy only. The high-intensity changes were most prominent in the frontal lobes in two of these children. The children with white matter changes were significantly younger than those with normal MRI (2.8 vs. 7.4 years; mean). There was no correlation between neuropsychological tests and white matter changes, except in attention and in tests referring to the frontal areas in general. CONCLUSIONS White matter changes are occasionally observed during therapy with the current Nordic protocols. Young children may be more susceptible to developing white matter changes after repeated intravenous methotrexate injections. There is no systematic correlation between neuropsychological deficits and MRI findings.


Journal of Neurosurgery | 2009

Hypertension and diabetes as predictors of early death after spontaneous intracerebral hemorrhage

Sami Tetri; Seppo Juvela; Pertti Saloheimo; Juhani Pyhtinen; Matti Hillbom

OBJECT Previous investigators have suggested that a high mean arterial blood pressure (MABP) and an elevated plasma glucose level at admission are associated with a poor outcome after hemorrhagic stroke. It remains unclear, however, whether hypertension and diabetes are responsible for this effect. High admission MABP and plasma glucose levels may also be markers of other factors such as stroke severity. METHODS The authors retrospectively investigated the role of a high admission MABP and plasma glucose level together with other predictors of early death among 379 nonsurgical patients with spontaneous intracerebral hemorrhages (ICHs) who were admitted to the stroke unit of Oulu University Hospital. RESULTS The 3-month mortality rate was 28%. The patients who died within 3 months of ICH had significantly higher plasma glucose levels and MABPs at admission (p < 0.001). After adjustments for patient sex, age, size and location of hematoma, Glasgow Coma Scale score at admission, presence of intraventricular hemorrhage, history of cardiac disease, and previous use of warfarin, history of diabetes (relative risk 1.61, 95% CI 1.03-2.53, p < 0.05) and high MABP at admission (relative risk 1.01 per mm Hg, 95% CI 1.00-1.02, p < 0.05) remained independent predictors of death 3 months after ICH. A high admission plasma glucose level and history of hypertension were not independent predictors of death. CONCLUSIONS A high MABP at admission was found to be an independent predictor of early death in patients with ICH. History of hypertension was not responsible for the effect. Admission hyperglycemia appeared to be a stress response to the severity of the bleeding, whereas diabetes predicted early death.


Schizophrenia Research | 2005

Hippocampus and amygdala volumes in schizophrenia and other psychoses in the Northern Finland 1966 birth cohort

Päivikki Tanskanen; Juha Veijola; Ulla K. Piippo; Marianne Haapea; Jouko Miettunen; Juhani Pyhtinen; Edward T. Bullmore; Peter B. Jones; Matti Isohanni

Structural brain differences have been reported in many studies with schizophrenia, but few have involved a general population birth cohort. We investigated differences in volume, shape and laterality of hippocampus and amygdala in patients with schizophrenia, all psychoses and comparison subjects within a large general birth cohort sample, and explored effects of family history of psychosis, perinatal risk and age-at-onset of illness. All subjects with psychosis from the Northern Finland 1966 birth cohort were invited to a survey including MRI scan of the brain, conducted in 1999-2001. Comparison subjects not known to have psychosis were randomly selected from the same cohort. Volumes of hippocampus and amygdala were measured in 56 subjects with DSM-III-R schizophrenia, 26 patients with other psychoses and 104 comparison subjects. Small hippocampal volume reductions in schizophrenia (2%) and all psychoses (3%) were not significant when adjusted for total brain volume. The shape of hippocampus in schizophrenia did not differ significantly from comparison subjects. Right hippocampus and amygdala were significantly larger than the left in all groups. Mean amygdala volume in schizophrenia or all psychoses did not differ from comparison subjects. Patients with family history of psychosis had larger hippocampus than patients without. Neither perinatal risk nor age-at-onset of illness had any effect on hippocampal or amygdala volumes. Small hippocampal volume reduction in schizophrenia and all psychoses was not disproportionate to reduced whole brain volume in this population-based sample. Perinatal events that have been suggested as of etiological importance in structural pathology of psychosis had no effect.


Neuroradiology | 1994

Late cranial MRI after cranial irradiation in survivors of childhood cancer.

Eija Pääkkö; Kimmo Talvensaari; Juhani Pyhtinen; Marjatta Lanning

We carried out MRI on 43 survivors of childhood cancer after different treatment protocols with or without cranial radiotherapy. They were free of disease, therapy having been discontinued 2–20 years earlier. Treatment had been for various malignancies, excluding brain tumours; 27 had received cranial irradiation for acute lymphoblastic leukaemia (ALL) or lymphoma. Two asymptomatic young women treated for ALL had falx meningiomas. White matter changes, low intensity foci (representing calcification or old haemorrhage) and heterogeneous intensity focic old haemorrhages) were seen only in patients who had undergone radiotherapy. Because of the possibility of benign, potentially curable brain tumours occurring after cranial irradiation, it may be wise to carry out occasional cranial imaging in the follow-up of these patients. No routine imaging follow-up is needed after chemotherapy alone.


Neuroradiology | 1998

Intracranial arterial dissection

O. Pelkonen; T. Tikkakoski; S. Leinonen; Juhani Pyhtinen; K. A. Sotaniemi

Abstract We review the angiographic and CT findings, precipitating factors and clinical features in nine patients with ten intracranial arterial dissections. The internal carotid artery was involved in five cases, the vertebral artery in four and the posterior inferior cerebellar artery in one. Angiography revealed irregular stenosis in four cases, irregular stenosis and a pseudoaneurysm in two, irregular stenosis and irregular dilatation in one, arterial occlusion in two and a pseudoaneurysm in one. CT demonstrated an infarct in four cases, a dense middle cerebral artery in two and subarachnoid haemorrhage in one. A possible precipitating factor was identified in five cases. Six patients recovered well, while three had persisting neurological deficits.


Clinical Neurophysiology | 2004

Cardiovascular autonomic dysfunction correlates with brain MRI lesion load in MS

Anne Saari; Uolevi Tolonen; Eija Pääkkö; Kalervo Suominen; Juhani Pyhtinen; K. A. Sotaniemi; Vilho V. Myllylä

OBJECTIVE The aim of the present study was to investigate the cardiovascular autonomic control in clinically definite multiple sclerosis (MS) patients with a standardised battery of cardiovascular tests and to correlate these findings with the brain magnetic resonance imaging (MRI) lesion load. METHODS Fifty-one patients with MS and 50 healthy controls were studied. Brain MRI was performed in all patients showing typical MS lesions. The cardiovascular tests were carried out using a standardised battery. RESULTS Heart rate (HR) responses to deep breathing (P < 0.05) and tilt table testing (P < 0.001) were significantly decreased in MS patients when compared to those of the controls. Blood pressure (BP) responses in the tilt table test were also impaired in MS patients (diastolic P < 0.001, systolic P < 0.05). Of the different brain areas investigated the total volume of the midbrain MRI lesions (P < 0.05) was the one most clearly associated with the impaired BP responses. CONCLUSIONS MS results in both reduced HR variation and decreased BP reactions indicating disturbed cardiovascular regulation. In particular, the midbrain lesions found in MS are associated with cardiovascular dysfunction.

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Matti Hillbom

Oulu University Hospital

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