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Biomedical subjects

L Valanne

Publications and source records attributed to L Valanne.

At least 37 records · Page 2Linked to original sources
PubMed1998

Muscle-eye-brain disease: clinical features, visual evoked potentials and brain imaging in 20 patients.

Clinical features, magnetic resonance imaging and visual evoked potentials were analysed and correlated in 20 Finnish patients with muscle-eye-brain disease. Significantly enhanced visual evoked potentials were found in 15 patients (giant in 14 of them). Magnetic resonance images were available in 17 cases. The images of 12 patients with giant visual evoked potentials showed typical brain malformation pachygyria with a nodular cortical surface i.e. cobblestone cortex, midline defect and hypoplastic pons but no significant abnormalities in the grey-white matter. One male had typical structural changes but flat visual evoked potentials. His extreme hydrocephalus with optic nerve compression may explain the findings. No structural changes on magnetic resonance images were found in the remaining four patients; however, in two of them marked alterations in the white matter were found. Three of these patients showed normal and one flat visual evoked potentials. Only one patient with giant visual evoked potentials and typical structural findings on magnetic resonance imaging had changes in a large area in the white matter (several attacks of status epilepticus might have caused the alterations in the white matter). Thus, the combination of giant visual evoked potentials and typical structural changes on magnetic resonance imaging with normal intensities of white matter and deep grey matter seems to be a good marker for patients with muscle-eye-brain disease.

Abnormalities, Multiple↗
PubMed1998

Neuroradiologic findings in children with mitochondrial disorders.

PURPOSE: We report the neuroradiologic findings in 25 children with various mitochondrial diseases. METHODS: Twenty-two children with a mitochondrial disorder had MR imaging of the brain and three children had CT studies. In all cases, the diagnosis was based on examination of muscle morphology, analysis of oxygen consumption and respiratory chain enzyme activity in isolated muscle mitochondria, and analysis of rearrangements of the mitochondrial DNA. RESULTS: Fifteen patients were found to have the classical syndromes of mitochondrial diseases. Four children had Kearns-Sayre syndrome, but only one had the typical neuroradiologic findings of basal ganglia and brain stem lesions, T2 hyperintensity of the cerebral white matter, and cerebellar atrophy; the others had nonspecific or normal findings. Eight patients had Leigh syndrome, and all showed changes in the putamina. Involvement of the caudate nuclei, globus pallidi, thalami, and brain stem was common, and diffuse supratentorial white matter T2 hyperintensity was seen in two of these patients. Three patients had mitochondrial encephalopathy with lactic acidosis and strokelike episodes (MELAS), with infarctlike lesions that did not correspond to the vascular territories. Ten children with complex I or IV deficiencies and abnormal muscle morphology had nonspecific imaging findings, such as atrophy and abnormal or delayed myelination. One patient with combined complex I and IV deficiency had extensive white matter changes. None of the patients with clinical encephalopathy had normal findings. CONCLUSION: MR imaging is helpful in the diagnosis of the classical mitochondrial diseases; however, nonspecific findings are common.

Adolescent↗
PubMed1997

Radiological signs in newborns exposed to primary Toxoplasma infection in utero.

A total of 44 181 serum samples from 16 733 pregnant women were analyzed for findings suggesting primary Toxoplasma infection. Thirty-seven newborns exposed to maternal primary Toxoplasma infection in utero were studied prospectively with ultrasound, CT, and MRI for signs of intrauterine infection. Their mothers had been treated during pregnancy, and all infants were treated. The children were assigned to three groups according to their mothers' serological status, and the radiological results were compared with the clinical outcome. Although radiological signs were scarce, ultrasound findings combined with maternal serology were found to be significantly related to clinical outcome.

Abdomen↗
PubMed1997

Subcortical type cognitive impairment in herpes zoster encephalitis.

Nine immunocompetent patients with acute herpes zoster encephalitis (HZE) were studied with the help of neurological investigations. All patients were treated with acyclovir. Neuropsychological performance was compared with that of a group of 16 healthy controls. Computed tomography of the head showed infarct-like hypodense lesions in two patients, involving the internal capsule in one case and the temporoparietal cortex and white matter in another. Hypoperfusion shown by single photon emission computed tomography, mostly involving the frontal areas bilaterally, was seen in six of the seven patients examined. Hyperperfusion as seen in herpes simplex encephalitis was not encountered. One patient remained mildly demented, but all the other patients recovered relatively well. Neuropsychological examination after acyclovir treatment showed a decline in memory and speed of cognitive processes, without circumscribed neuropsychological deficits. Six of the nine patients showed behavioural disinhibition, and mood changes were also observed. Memory impairment in HZE was not as global or as severe as is described after encephalitis due to herpes simplex virus. In HZE both the brain perfusion pattern and the neuropsychological test profile showed features compatible with subcortical dysfunction.

Adult↗
PubMed1997

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency with the G1528C mutation: clinical presentation of thirteen patients.

Long-chain 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase is one of three enzyme activities of the mitochondrial trifunctional protein. We report the clinical findings of 13 patients with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency. At presentation the patients had had hypoglycemia, cardiomyopathy, muscle hypotonia, and hepatomegaly during the first 2 years of life. Seven patients had recurrent metabolic crises, and six patients had a steadily progressive course. Two patients had cholestatic liver disease, which is uncommon in beta-oxidation defects. One patient had peripheral neuropathy, and six patients had retinopathy with focal pigmentary aggregations or retinal hypopigmentation. All patients were homozygous for the common mutation G1528C. However, the enoyl-CoA hydratase and 3-ketoacyl-CoA thiolase activities of the mitochondrial trifunctional protein were variably decreased in skin fibroblasts. Dicarboxylic aciduria was detected in 9 of 10 patients, and most patients had lactic acidosis, increased serum creatine kinase activities, and low serum carnitine concentration. Neuroradiologically there was bilateral periventricular or focal cortical lesions in three patients, and brain atrophy in one. Only one patient, who has had dietary treatment for 9 years, is alive at the age of 14 years; all others died before they were 2 years of age. Recognition of the clinical features of long-chain 3-hydroxyacyl-CoA deficiency is important for the early institution of dietary management, which may alter the otherwise invariably poor prognosis.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1997

Autosomal dominant progressive external ophthalmoplegia with multiple deletions of mtDNA: clinical, biochemical, and molecular genetic features of the 10q-linked disease.

Autosomal dominant progressive external ophthalmoplegia (adPEO) is a mitochondrial disease characterized by accumulation of multiple large deletions of mtDNA in patients' tissues. We previously showed that the disease is genetically heterogeneous by assigning two nuclear loci predisposing to mtDNA deletions: one on chromosome 10q 23.3-24.3 in a Finnish family and one on 3p 14.1-21.2 in three Italian families. To reveal any locus-specific disease features, we report here the clinical, biochemical, and molecular genetic characteristics of the 10q-linked disease in the single family reported to date. All seven patients and four asymptomatic subjects had ragged-red fibers and multiple deletions of mtDNA in their muscle. Ptosis and external ophthalmoplegia were the major clinical findings, and depression or avoidant personality traits were frequently, but not consistently, present in the subjects carrying mutant mtDNA. In six of the subjects with mutant mtDNA, the activities of the respiratory chain complexes I or IV, or both, were below or within the low normal range. Two autopsy studies revealed the characteristic distribution of mutant mtDNA in these patients: highest proportion of mutant mtDNA is found in different parts of the brain, followed by the skeletal and ocular muscle, and the heart.

Adult↗
PubMed1997

Unilateral hyperfusion in brain-perfusion SPECT predicts poor prognosis in acute encephalitis.

We studied 88 patients with acute encephalitis using hexamethylpropyleneamine oxime and single photon emission computed tomography (SPECT). All patients had been initially treated with intravenous acyclovir. The etiology could be disclosed in 37 patients (42%), which included 15 patients with herpes simplex encephalitis, 7 with varicella-zoster encephalitis, and 29 with other encephalitides (Mycoplasma, adenovirus, influenza, rotavirus, rubella, Epstein-Barr, arbovirus, syphilis, and tuberculosis). Unilateral hyperperfusion in SPECT was an independent predictor of poor prognosis, whereas neither clinical outcome variables, such as seizures, state of consciousness, and focal neurologic findings, nor CSF or EEG findings were not. Focal unilateral hyperperfusion is an indicator of severe inflammation of the brain tissue and predicts a poor outcome as assessed in terms of activities of daily living after recovery.

Acute Disease↗
PubMed1996

Laminar cortical necrosis in MELAS syndrome: MR and neuropathological observations.

Laminar cortical necrosis has been described in many conditions of cellular energy depletion, such as hypoxia and hypoglycemia. In MELAS, a genetic defect in mitochondrial protein synthesis leads to impairment of oxidative phosphorylation, with subsequent insufficient energy production within the cell. Neurons are more vulnerable to energy depletion than glial cells and vascular elements, and among the layers of the cerebral cortex the lower laminae are more vulnerable than the superficial layers. We studied a child with severe MELAS syndrome two months before death with MR and compared the images to autopsy findings, including macroscopic specimens and light and electron microscopy. The MR images showed an excellent correlation with the neuropathological results and displayed the various degrees of damage to the brain tissue caused by deficient energy production. Acute laminar cortical necrosis was seen as swelling of the cortex with intracortical hyperintense bands in T2-weighted images. The subacute stage with focal cortical hemorrhage was displayed as hyperintensity of the gyral surface in T1-weighted and hypointensity in T2-weighted images, with T2-hyperintensity and swelling of the rest of the cortex and underlying white matter. Severe cortical atrophy represented the chronic stage.

Atrophy↗
PubMed1996

Cognitive impairment after acute encephalitis: comparison of herpes simplex and other aetiologies.

OBJECTIVE: To compare the cognitive defects after acute acyclovir treated herpes simplex encephalitis with those after other types of acute encephalitis. METHODS: Seventy seven consecutive patients between 1985 and 1995 and 29 normal controls were studied. Of the 77 patients without concomitant neurological conditions, 17 had herpes simplex, one virus encephalitis (HSVE group), 27 had some other identified aetiology (non-HSVE group), and in 33 patients the cause was unknown. Acyclovir treatment was started less than four days after the first mental symptoms in 12 of 17 patients with HSVE. A thorough neuropsychological assessment was carried out about one month after the onset. RESULTS: The HSVE group had deficits in verbal memory, verbal-semantic functions, and visuoperceptual functions more often than the non-HSVE group. The risk for cognitive defects was twofold to four-fold in the patients with HSVE compared with the non-HSVE patients. Two (12%) of the patients with HSVE and 12 (44%) of the non-HSVE patients were cognitively intact. Six patients with HSVE (46%) and 17 (89%) non-HSVE patients later returned to work. The lesions on CT or MRI were bilateral only in one patient with HSVE. The defects in the three patients with adenovirus infection were severe and resembled the amnesia after HSVE. Cognitive impairment, not previously reported, was found in encephalitis after rotavirus infection and epidemic nephropathy. CONCLUSION: The recovery in the HSVE group was better than expected based on the medical literature. On the other hand there were surprisingly severe cognitive defects in encephalitis after other viruses. With early acyclovir treatment patients with the least severe HSVE were equivalent to those with non-HSV encephalitis with good outcome whereas those with the most severe non-HSV encephalitis were equivalent to those with HSVE with poor outcome.

Acute Disease↗
PubMed1995

Isolated retrograde amnesia for autobiographical material associated with acute left temporal lobe encephalitis.

Retrograde amnesia for autobiographical material in the absence of anterograde amnesia or other memory disturbances was found in a patient with acute viral encephalitis. Memory loss showed a temporal gradient, but new learning was spared. Both brain perfusion imaging with 99mTc-HMPAO SPECT, and EEG localized the lesion in the left temporal lobe while CT and MRI were normal. This observation supports the anatomical differentiation between the different memory functions. The uncommon combination of isolated retrograde amnesia without other neuropsychological findings may raise the doubt of psychogenic aetiology, which in this case was refuted.

Adult↗
PubMed1995

Infantile-onset spinocerebellar ataxia: MR and CT findings.

PURPOSE: To report the MR and CT findings in a hereditary disease, infantile-onset spinocerebellar ataxia (IOSCA). METHODS: We studied the brains of 17 patients with infantile-onset spinocerebellar ataxia with CT and/or MR to determine the presence of cerebellar and brain stem atrophy and parenchymal lesions. RESULTS: Cerebellar cortical atrophy was seen in 13 patients. The degree of atrophy correlated with increasing age and clinical deterioration. Brain stem atrophy was seen in 8 patients. It was never severe, and the basis pontis was not flattened even in the most severe cases. Hyperintense lesions were noted within the white matter of cerebellum, in the dentate nuclei, and in the middle cerebellar peduncles in 3 patients. The upper cervical cord was seen in 9 patients and showed mild to moderate atrophy in 4. The basal ganglia and cerebral hemispheres were normal, except in 2 patients transient cortical and subcortical lesions developed during episodes of status epilepticus; mild cortical brain atrophy subsequently developed. CONCLUSION: The brain MR and CT findings of patients with infantile-onset spinocerebellar ataxia correspond to the neuropathologic entities of cerebellar cortical atrophy, olivopontocerebellar atrophy, and spinocerebellar atrophy. The appearance of the findings followed a uniform time sequence from cerebellar cortical atrophy in the early stage of the disease to olivopontocerebellar atrophy and spinocerebellar atrophy in the later stage. The severity of atrophy correlated with clinical deterioration.

Adolescent↗
PubMed1994

MRI of the brain in muscle-eye-brain (MEB) disease.

Muscle-eye-brain (MEB) disease belongs to the spectrum of rare congenital syndromes with migration disorders of the brain and muscular dystrophy, along with the Walker-Warburg syndrome and Fukuyama congenital muscular dystrophy. Their features overlap, and differential diagnosis presents some difficulties. We examined the brain of 10 patients with MEB using high-field MRI and found a uniform pattern consisting of a pachygyria-type cortical migration disorder, septal and corpus callosum defects and severe hypoplasia of the pons in 7 of them.

Adolescent↗
PubMed1993

Transient ischemic cerebral lesions during induction chemotherapy for acute lymphoblastic leukemia.

Ninety children were treated for acute lymphoblastic leukemia or non-Hodgkin lymphoma during 1986 through 1992 in the Children's Hospital, University of Helsinki, in Finland. During induction chemotherapy, nine of the children had visual hallucinations progressing to confusion and seizure. The symptoms were often preceded by severe constipation and significantly elevated blood pressure. Neuroradiologic examinations showed bilateral cortical or subcortical white matter lesions. Despite the stroke like manifestations, the lesions were reversible. The triangular shape and location of the lesions in the watershed areas between the major cerebral arteries suggest vascular ischemia as the cause.

Adolescent↗
PubMed1992

Radiological study of the brain at various stages of human immunodeficiency virus infection: early development of brain atrophy.

One hundred and one persons infected with human immunodeficiency virus (HIV-1), in whom other central nervous system infections or diseases were excluded, underwent brain CT and/or MRI at various stages of HIV-1 infection: 29 were asymptomatic (ASX), 35 had lymphadenopathy syndrome (LAS), 17 had AIDS-related complex (ARC), and 20 had AIDS. A control group of 32 HIV-1-seronegative healthy persons underwent brain MRI. The most common finding was brain atrophy, found in 9% of controls, and 31% of ASX cases, 29% of LAS, 59% of ARC and 70% of AIDS. Even the difference between the ASX or LAS groups and controls was significant. The changes were bilateral and symmetrical, and they were more severe at later stages of infection. Infratentorial atrophy was seen in the early stages; supratentorial atrophy became more pronounced at ARC, and generalized atrophy was typical of AIDS. Non-specific small hyperintense foci were found on MRI in 13% of controls and 6-15% of the infected groups. Larger, diffuse, bilateral white matter infiltrates were detected in 4 demented patients with AIDS. Four patients with AIDS and 1 with LAS had focal hyperintense lesions in the internal capsules, lentiform nuclei or thalamus, often bilateral on MRI. One patient with AIDS, examined with CT only, had low density in the lentiform nucleus. Loss of brain parenchyma can occur at an early stage of HIV-1 infection, and the atrophic process becomes more intense at later stages (ARC and AIDS). Parenchymal infiltration, seen as hyperintense areas on MRI, is most often associated with severe clinical symptoms, in the later stages of the disease.

Acquired Immunodeficiency Syndrome↗
PubMed1992

CNS in congenital muscular dystrophy without mental retardation.

We have evaluated the CNS findings of 30 patients with congenital muscular dystrophy and normal mental development. The intelligence was estimated by psychological testing or school performance. There were more children of above average intelligence than expected. Neuroradiological examination was done to 15/17 patients still alive. White matter changes were seen in five and cerebral atrophy in four patients. Three patients had epilepsy, two mild, one drug resistant. The EEG did not reveal any common pattern, though there were various abnormalities in several children.

Achievement↗