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K Partanen

Publications and source records attributed to K Partanen.

At least 19 recordsLinked to original sources
PubMed1995

Hippocampal atrophy, acute THA treatment and memory in Alzheimer's disease.

We designed the present study to investigate the hypothesis that progression of hippocampal pathology may decrease the therapeutic effects of anti-cholinesterase drug, tetrahydroaminoacridine, on memory functioning in Alzheimer's disease (AD) patients. Memory, visuoconstructive, executive and vigilance functions were assessed after administration of placebo (p.o.; two placebo sessions) and tetrahydroaminoacridine (one session for 25 and 75 mg, p.o.). Eight patients performed better on list learning test during tetrahydroaminoacridine 75 mg than after placebo or tetrahydroaminoacridine 25 mg. The responders performed during baseline examination better than the non-responders in executive and some declarative memory functions, and had higher MMSE scores than the non-responders. The responders had larger left and right hippocampi than the non-responders. The hippocampal volume correlated with list learning performance. The results suggest that severe hippocampal atrophy may block memory improving effect of an anticholinesterase drug, tetrahydroaminoacridine.

Alzheimer Disease↗
PubMed1995

Volumes of hippocampus, amygdala and frontal lobes in the MRI-based diagnosis of early Alzheimer's disease: correlation with memory functions.

We studied the usefulness of measuring volumes of the hippocampus, amygdala and frontal lobes with coronal magnetic resonance imaging (MRI) scans in the diagnosis of early Alzheimer's disease (AD). We examined 32 patients diagnosed according to the NINCDS-ADRDA criteria of probable AD and 16 age-matched healthy cognitively normal controls. The AD patients had mild dementia with a mean score of 22.8 in the Mini-Mental Status Examination (MMSE). We used a 1.5 T magnetic resonance imager and normalized the volumes for brain area. The AD patients had significantly smaller volumes of the right and the left hippocampus (-38%) (ANOVA, p < 0.0001) and the left frontal lobe (-16%, p < 0.05) compared to controls. The reductions in volumes of the right frontal lobe (-13%), the right amygdala (-14%) or the left amygdala (-18%) were not statistically significant. In the discriminant function analysis which included the volumes of the hippocampus, amygdala, and the frontal lobes and age, the volumes of the left and right hippocampus, the left and right frontal lobe, and the right amygdala entered the model and we could correctly classify 92% of the subjects into AD and control groups (Chi-square 42.6, df 5, p < 0.001). By using the volumes of the hippocampus, the frontal lobes or the amygdala on their alone, the correct classification was achieved in 88%, 65% and 58% of the subjects, respectively. In addition, in AD patients the volumes of the left hippocampus correlated significantly with the MMSE score and with immediate and delayed verbal memory; the smaller the volume the more impaired was their performance. Our data indicate that measurements of volumes of the hippocampus might be useful in diagnosis of early AD.

Aged↗
PubMed1995

Habituation of auditory N100 correlates with amygdaloid volumes and frontal functions in age-associated memory impairment.

We studied the habituation of auditory N100 responses in subjects with age-associated memory impairment (AAMI) and in healthy age-matched volunteers. The findings were correlated with volumes of the amygdala, hippocampus, and frontal lobe measured by magnetic resonance imaging (MRI), as well as with subjects' performance on tests assessing frontal lobe functions and memory. Habituation of N100 did not differ across AAMI subjects and controls. However, in AAMI subjects there was a significant correlation between habituation of N100 and volumes of the amygdala; the more reduced habituation, the smaller volume. In addition, decline in habituation of N100 correlated with impaired performance on a visual memory test (Heaton Visual memory test (Heaton Visual Retention Test; r = 0.77; p < 0.001) and impairment on tests assessing frontal functions (Verbal Fluency, Trail Making Test, and Stroop). Habituation of N100 was not related to age or sex. To our knowledge this is the first study to demonstrate a relationship between habituation of evoked responses, MRI volumetric measures, and performance on psychometric tests. The results suggest that impaired memory and frontal lobe functions in AAMI subjects may be associated with poor habituation of N100. Since habituation reflects focusing of attention to relevant features of stimuli, impairment of this mechanism and subsequent defective memory trace formation may contribute to the observed deficits on memory tests.

Aged↗
PubMed1995

Volumes of hippocampus, amygdala and frontal lobe in Alzheimer patients with different apolipoprotein E genotypes.

An increased frequency of apolipoprotein E E4 allele has been reported in patients with late onset Alzheimer's disease. Apolipoprotein E participates in the transport of cholesterol and other lipids and interferes with the growth and regeneration of both peripheral and central nervous system tissues during development and after injury. Apolipoprotein E is also implicated in synaptogenesis. Apolipoprotein E isoforms differ in binding to amyloid-beta-protein and tau protein in vitro. Here, we wanted to study the effect of apolipoprotein E genotype on the magnitude of damage in the hippocampus, where a marked synapse loss exists in Alzheimer's disease. We measured by magnetic resonance imaging the volumes of the hippocampus, amygdala, and frontal lobes in the three Alzheimer subgroups: patients with 2, 1 or 0 E4 alleles. We also investigated the profile of deficits on tests assessing memory, language, visuospatial, executive, and praxic functions of these Alzheimer subgroups. All Alzheimer patients were at early stage of the disease. We found that Alzheimer patients with E4/4 genotype (N = 5) had smaller volumes of the hippocampus and the amygdala than those with E3/4 (N = 9) and those with E3/3 or E2/3 (N = 12). The difference was significant for the right hippocampus (-54% of control) and the right amygdala (-37% of control). The volumes of the frontal lobes were similar across the Alzheimer subgroups. The patients with E4/4 also showed lowest scores on delayed memory tests and differed from E3/3, 3/2 patients in the list learning test (< 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Abnormal regional benzodiazepine receptor uptake in the prefrontal cortex in patients with panic disorder.

The neuroanatomical networks involved in the initiation of panic attack and the maintenance of panic disorder are poorly understood. This study aimed to elucidate the possible abnormalities in benzodiazepine receptor uptake in the brain of patients with panic disorder. Seventeen unmedicated patients with panic disorder were investigated using 123I-iomazenil single photon emission tomography (SPET). Seventeen healthy age- and sex-matched volunteers served as controls. The SPET scan was taken 90 min after injection of tracer. Eleven of 17 patients (65%) showed an increased (> 2 S.D. higher than the mean of the controls) right-to-left ratio of benzodiazepine receptor uptake in the prefrontal cortex. Also, the mean right-to-left ratio of benzodiazepine receptor uptake in all 17 patients with panic disorder was higher than in the controls (P < 0.001). Our SPET study demonstrated focally altered benzodiazepine receptor uptake in the prefrontal cortices in patients with panic disorder. Magnetic resonance imaging indicated that the affected region was located in the right middle and inferior frontal gyri. The deterioration in information processing in the right prefrontal cortex may be implicated in the generation of panic disorder.

Female↗
PubMed1995

Hemodynamic effects of carotid endarterectomy by magnetic resonance flow quantification.

BACKGROUND AND PURPOSE: Blood flow can be evaluated non-invasively using magnetic resonance phase-contrast flow quantification. The purpose of this prospective study was to assess the feasibility of this method and to evaluate the hemodynamic effects of carotid endarterectomy. METHODS: Volumetric flow rates and peak systolic velocities of the internal and common carotid and the vertebral arteries were measured by magnetic resonance flow quantification. Sixteen patients undergoing 18 endarterectomies had complete flow data recorded preoperatively and 3 days after surgery. RESULTS: The inverse correlation between the angiographic stenosis degree and the preoperative flow rate in the corresponding internal carotid artery was highly significant (r = -.69, P < .001). After endarterectomy, the mean flow in the ipsilateral internal carotid artery improved from 143 to 233 mL/min (P < .001). The mean peak systolic velocity increased from 23 to 37 cm/s (P < .001). No significant changes were seen in the contralateral carotid or the vertebral arteries. The mean total blood flow improved by 81 mL/min (P = .08). In the severely stenosed bifurcations (70% to 99%, n = 11), the flow rate improved by 106 mL/min and in the moderately (30% to 69%, n = 4) or mildly (< 30%, n = 3) stenosed bifurcations by 63 mL/min. If the contralateral carotid artery was occluded or severely stenosed, the improvement was 164 mL/min. CONCLUSIONS: Magnetic resonance flow quantification provides a useful tool for the follow-up of the hemodynamic effects of carotid endarterectomy. Our results indicate that surgery is followed by a significant increase of blood flow in the ipsilateral carotid artery and that there appear to be differences in flow increase between subgroups of patients with different degrees of stenosis.

Aged↗
PubMed1995

The interuncal distance in Alzheimer disease and age-associated memory impairment.

PURPOSE: To examine the value of measurement of the interuncal distance in the diagnosis of mild to moderate Alzheimer disease. METHODS: We measured interuncal distance from coronal MR scans acquired on a 1.5-T imager. We estimated interuncal distance from a total of 141 subjects: 54 patients diagnosed according to the National Institute of Neurological and Communicative Disorders and the Alzheimer's Disease and Related Disorders Association criteria of probable Alzheimer disease, 40 subjects fulfilling the National Institute of Mental Health criteria of age-associated memory impairment, 27 healthy cognitively normal older control subjects, and 20 control subjects younger than 50 years of age. For comparison we normalized interuncal distance for a horizontal line drawn through the inner cranium at the level of the uncus (interuncal distance/intracranial width ratio), for the brain area (interuncal distance/brain area) and for the intracranial area (interuncal distance/intracranial area). RESULTS: The standard interuncal distance and the interuncal distance/intracranial width differed between the young control subjects and the other groups, but did not differ among the control, age-associated memory impairment, and Alzheimer disease groups. The Alzheimer disease group had significantly greater interuncal distance/intracranial area and interuncal distance/brain area compared with age-matched controls. A considerable overlap was found, however, in the values of patients with Alzheimer disease and control subjects. The cutoff point of 30 mm for interuncal distance yielded 37% sensitivity and 72% specificity to distinguish patients with Alzheimer disease from nondemented elderly subjects. Interuncal distance was not significantly related to the clinical severity of Alzheimer disease as assessed by Clinical Dementia Rating Scale and Mini-Mental Status Examination. Instead, there was a strong correlation between standard and normalized interuncal distance and age in the whole study population and in nondemented subjects. CONCLUSIONS: Our results showed that in a series of 54 patients with mild to moderate Alzheimer disease, interuncal distance was not a reliable diagnostic tool. The study also confirmed the strong age dependence for interuncal distance.

Adult↗
PubMed1995

Defecography.

Defecography, a dynamic imaging modality, plays an important role in the diagnosis of functional and morphologic abnormalities of the anorectal region. We have here summarized the principle and techniques as well as observations of defecography, with special emphasis on morphologic measurements, clinical relevance, and limitations. The application of MR imaging in examination of anorectal function has also been addressed.

Barium Sulfate↗
PubMed1994

Do seizures cause neuronal damage? A MRI study in newly diagnosed and chronic epilepsy.

It is a matter of dispute whether or not recurrent epileptic seizures cause neuronal damage in the human brain. We approached this question by measuring the volumes of the amygdala, hippocampus and parahippocampal gyrus with magnetic resonance imaging in 15 controls, 13 unmedicated patients with newly diagnosed epilepsy and 16 patients with chronic drug-refractory epilepsy. In all patients, the seizure origin was in the temporal lobe region and the seizure aetiology was unknown. Newly diagnosed epilepsy patients with seizure lateralization on the left had increased hippocampal right-left difference (p < 0.01) and right/left ratio (p < 0.05) compared with controls. Patients with chronic epilepsy and lateralization on the left had increased hippocampal right-left difference (p < 0.05) and right/left ratio (p < 0.05) compared with controls. In this patient group, the volume of the left hippocampus was 16% smaller than in controls (p < 0.01). The rostral portion of the parahippocampal gyrus was 12% smaller than in controls (p < 0.01). In chronic epilepsy patients with lateralization on the right, we found a statistically non-significant decrease (13%) in the right hippocampal volume compared with controls. In this patient group, the amygdaloid right-left difference (p < 0.05) and right/left ratio (p < 0.05) were decreased compared with controls. The present cross-sectional study provides evidence that mild hippocampal damage is already present in the early stages of epilepsy. Hippocampal damage is more severe in patients with a long history of recurrent generalized seizures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Reduced N-acetylaspartate concentration in temporal lobe epilepsy by quantitative 1H MRS in vivo.

We used proton magnetic resonance spectroscopy (1H MRS) to determine concentrations of N-acetylaspartate (NAA), creatine and choline in vivo (63 MHz) and in vitro (400 MHz) in seven patients undergoing surgical treatment of intractable temporal lobe epilepsy (TLE). Nine healthy volunteers were used as controls for in vivo MRS. NAA concentrations in vivo on the ipsilateral and contralateral sides were 6.5 +/- 1.3 (s.d.) and 7.9 (+/- 2.1) mmol l-1, respectively and 8.6 (+/- 0.8) mmol l-1 in the volunteers. NAA concentration in vitro was 3.2 (+/- 0.9) mumol g-1 wet weight (ww) and the corresponding concentration from the macroscopically intact brain tissue was 4.7 (+/- 1.0) mumol g-1 ww. Thus, in vivo quantitative 1H MRS identified the size of seizure focus in patients with temporal lobe epilepsy.

Adolescent↗
PubMed1994

Increase in cerebral blood flow of right prefrontal cortex in man during orgasm.

The functional anatomy of human emotional responses has remained poorly understood, mainly because invasive experiments in humans are unacceptable due to ethical reasons. The new functional imaging techniques such as positron emission tomography and single photon emission computed tomography have made it possible to study the neurophysiology of living humans noninvasively. We studied the regional cerebral blood flow with semi-quantitative 99mTc-HMPAO single photon emission computed tomography in eight healthy right-handed heterosexual males during organism. The results showed decrease of cerebral blood flow during orgasm in all other cortical areas except in right prefrontal cortex, where the cerebral blood flow increased significantly (P < 0.005).

Adult↗
PubMed1994

Tumour-associated trypsin inhibitor in the diagnosis of pancreatic carcinoma.

The serum values of tumour-associated trypsin inhibitor (TATI) were measured in a prospective series of 97 patients with jaundice, 36 patients with unjaundiced cholestasis and 21 patients with suspicion of chronic pancreatitis or a pancreatic tumour, to assess its value in diagnosing pancreatic cancer. There were altogether 15 patients with cancer of the pancreas and 2 patients with cancer of the papilla of Vater. The highest serum TATI values were noticed in patients with choledocholithiasis, and raised values were also seen in patients with malignant disease of the liver or bile ducts. In the patients with pancreatic cancer, chronic pancreatitis or benign liver disease, the serum TATI values showed lower levels. The sensitivity of TATI in diagnosing pancreatic cancer was 41.1% with a specificity of 63.5% and an efficiency of 61.0%. In comparison to carcinoembryonic antigen (CEA), carbohydrate antigens CA 50, CA 242, tissue polypeptide antigen and tissue polypeptide-specific antigen, TATI showed a lower diagnostic value. When TATI was analysed in combination with the other markers (two tests positive), the combination of CEA with TATI reached the highest specificity (95.6%), efficiency (89.6%) and positive likelihood ratio (9.3). The results suggest that the diagnostic value of TATI is inferior to that of the established markers, but because of its different nature, it may be of help when used in combination as a complementary serum tumour marker in the diagnosis of pancreatic cancer.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1994

Late onset foot-drop muscular dystrophy with rimmed vacuoles.

We studied a family with late-onset (fifth or sixth decade) or asymptomatic hereditary myopathy of the anterior tibial muscle. The occurrence of the disease in two successive generations pointed out an autosomal dominant pattern of inheritance. The initial symptom was uni- or bilateral foot drop resembling peroneal paresis. Surprisingly many of the diagnosed patients were asymptomatic and considered themselves healthy whether there was any foot drop or not. The anterior tibial muscles were atrophic in patients with foot drop but the long toe extensors were usually and the short ones were always spared. Apparently the toe extensors could relieve the foot drop symptom. As shown by computed tomography there was often an early uni- or bilateral involvement of the semimembranosus muscle in males. The proband showed also a late involvement of the femoral biceps and the minor gluteal muscles. The muscles of the upper extremity were spared. The anterior tibial muscles had a characteristic myopathic alteration with rimmed vacuoles in histopathological study. This picture was most evident in latent cases without atrophy of the anterior tibial muscle, but with distinctly abnormal EMG of that muscle. Non-affected muscles showed only slight non-specific histopathological changes. We suggest that this disease is a new mild variety of autosomal dominant distal myopathy with rimmed vacuoles.

Adult↗
PubMed1994

A prospective study of serum tumour markers carcinoembryonic antigen, carbohydrate antigens 50 and 242, tissue polypeptide antigen and tissue polypeptide specific antigen in the diagnosis of pancreatic cancer with special reference to multivariate diagnostic score.

The aim of this study was to assess by a stepwise multivariate discriminant analysis the value of four current serum tumour markers - carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 50 and CA 242 and tissue polypeptide antigen (TPA) - and a new serum tumour marker, tissue polypeptide specific antigen (TPS), in the diagnosis of pancreatic cancer. The serum values were measured in a prospective series of patients with jaundice, with unjaundiced cholestasis and with a suspicion of chronic pancreatitis or a pancreatic tumour (n = 193). There were 24 patients with a cancer of the pancreas and two patients with a cancer of the papilla of Vater in this series. Our results showed that CA 50 (P < 0.001) and TPA (P < 0.01) were the best marker tests in predicting pancreatic malignancy. Also, the TPS (P = 0.07) and CA 242 (P = 0.08) tests showed marginally significant independent discriminating power, while the CEA test did not (P = 0.12). In order to sum up the contributions of different markers, a diagnostic score (DSI) was developed. The discrimination function was: DS1 = CA 50 x 1.75 + TPA x 0.62 + TPS x (-0.37) + CA 242 x (-1.21). The sensitivity of DS1 in detecting pancreatic cancer was 36% with a specificity of 90% and an efficiency of 82%. When the combination of CA 50 and TPA was used as a test, the discrimination function (DS2) was: DS2 = CA 50 x 0.69 + TPA x 0.67. The sensitivity of DS2 was 44% with a 88% specificity and an efficiency of 82%. According to this analysis, the further advantage gained by a computer-aided scoring system seems to be limited, since despite the considerably high specificity and efficiency its sensitivity remained low. In the present analysis the best combination in diagnosing pancreatic cancer was the combination of CA 50 and TPA.

Adult↗
PubMed1994

Diagnostic value of tissue polypeptide specific antigen in patients with pancreatic carcinoma.

We evaluated the clinical utility of a new tumor marker tissue polypeptide specific antigen (TPS) in the diagnosis of pancreatic carcinoma. Serum concentrations were determined in 113 patients with jaundice, in 18 patients with laboratory values suggesting cholestasis and in 60 patients with suspicion of chronic pancreatitis or pancreatic tumor. Twenty-four of these 191 patients had pancreatic carcinoma and 2 patients had carcinoma of the papilla of Vater. The highest median serum TPS value was detected in patients with malignant liver disease, but high median values were also measured in patients with pancreatic cancer, bile duct cancer or benign liver disease. The sensitivity of TPS was 50.0%, with a specificity of 73% and an efficiency of 70%. In comparison with carcinoembryonic antigen (CEA), CA 50 and CA 242, the TPS test showed lower sensitivity, but the differences in specificity and negative predictive value were considerably smaller. The utility of TPS as a complementary test was also analyzed. When TPS was combined with other marker tests, their specificities clearly improved, being highest in the combination of TPS and CA 242 (92.5%). In this combination, efficiency and positive likelihood ratio were also clearly better (85% and 5.6) than those of the marker tests alone. In conclusion, TPS seems less accurate than CEA, CA 50 or CA 242 in the diagnosis of pancreatic cancer, but because of its different nature it may be considered to be used as a complementary test.

Biomarkers, Tumor↗
PubMed1994

Volumetric MRI analysis of the amygdala and the hippocampus in subjects with age-associated memory impairment: correlation to visual and verbal memory.

Age-associated memory impairment (AAMI) is a common but disputed entity. It is unclear whether AAMI is a phenomenon of normal aging or an early sign of Alzheimer's disease. The present study aimed to identify possible structural abnormalities in the medial temporal lobe of AAMI subjects. We measured volumes of the hippocampus and amygdala by MRI in 16 AAMI subjects and in 16 age- and sex-matched controls and correlated the volumes with subjects' performance on two visual memory tasks (the Benton and the Heaton visual retention tests) and on a verbal memory task (the Buschke-Fuld Selective Reminding Test). The mean hippocampal and amygdaloid volumes normalized for brain size per se did not differ between the two study groups. In controls, but not in AAMI subjects, the right hippocampus was larger than the left. Accordingly, the volumetric asymmetry between the right and left hippocampi was smaller in AAMI subjects than in controls (Student's t test, p < 0.05). The volume of the right hippocampus (r = 0.37, n = 32, p < 0.05) and the magnitude of the asymmetry between the right and left hippocampi (r = 0.38, n = 32, p < 0.05) correlated with total score on the Benton test. We also found significant correlations between the amygdaloid volumes and the performance on visual memory tests but not with score on the verbal memory test.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Carotid stenosis by digital subtraction angiography: reproducibility of the European Carotid Surgery Trial and the North American Symptomatic Carotid Endarterectomy Trial measurement methods and visual interpretation.

PURPOSE: To evaluate different carotid stenosis estimation methods with digital subtraction angiography. METHODS: We assessed the intraobserver reproducibilty and interobserver variability of visual interpretation and the measurement methods used by the European Carotid Surgery Trial and the North American Symptomatic Carotid Endarterectomy Trial. Angiographic stenosis measurements according to both criteria were performed twice by a radiologist, a neurologist, and a vascular surgeon. Eighty bifurcations of consecutive symptomatic patients underwent 480 pairs of measurements. In addition, four radiologists estimated the stenoses visually. RESULTS: Intraobserver consistency was slightly better by the European (kappa, 0.86 to 0.94) than by the North American (kappa, 0.68 to 0.91) trial criteria or by visual interpretation (kappa, 0.79 to 0.81). No significant interobserver variability was found, except in the subgroup of mild stenoses by the North American Trial criteria. By kappa statistic, the interobserver agreement was excellent by the European trial method (kappa, 0.72 to 0.86), good by the North American trial method (kappa, 0.59 to 0.77), and good to excellent by visual evaluation (kappa, 0.68 to 0.88). The visual estimation agreed more closely with the European (kappa, 0.73 to 0.92) than with the North American trial (kappa, 0.55 to 0.74) criteria measurements. CONCLUSIONS: All three methods have good reproducibility in digital subtraction angiography. Interobserver differences become more important in the estimation of mild stenosis.

Adult↗