Evaluation of the INTERPRET decision-support system: can it improve the diagnostic value of magnetic resonance spectroscopy of the brain?

PURPOSE: We evaluated in a clinical setting the INTERPRET decision-support system (DSS), a software generated to aid in MRS analysis to achieve a specific diagnosis for brain lesions. METHODS: The material consisted of 100 examinations of focal intracranial lesions with confirmed diagnoses. MRS was obtained at 1.5 T using TE 20-30 ms. Data were processed with the LCModel for conventional analysis. The INTERPRET DSS 3.1. was used to obtain specific diagnoses. MRI and MRS were reviewed by one interpreter. DSS analysis was made by another interpreter, in 80 cases by two interpreters. The diagnoses were compared with the definitive diagnoses. For comparisons between DSS, conventional MRS analysis, and MRI, the diagnoses were categorised: high-grade tumour, low-grade tumour, non-neoplastic lesion. RESULTS: Interobserver agreement in choosing the diagnosis from the INTERPRET database was 75%. The diagnosis was correct in 38/100 cases, incorrect in 57 cases. No good match was found in 5/100 cases. The diagnostic category was correct with DSS/conventional MRS/MRI in 67/58/52 cases, indeterminate in 5/8/20 cases, incorrect in 28/34/28 cases. Results with DSS were not significantly better than with conventional MRS analysis. All definitive diagnoses did not exist in the INTERPRET database. In the 61 adult patients with the diagnosis included in the database, DSS/conventional MRS/MRI yielded a correct diagnosis category in 48/32/29 cases (DSS vs conventional MRS: p = 0.002, DSS vs MRI: p = 0.0004). CONCLUSION: Use of the INTERPRET DSS did not improve MRS categorisation of the lesions in the unselected clinical cases. In adult patients with lesions existing in the INTERPRET database, DSS improved the results, which indicates the potential of this software with an extended database.

Acute brain lesions on magnetic resonance imaging in relation to neurological outcome after cardiac arrest.

BACKGROUND: Magnetic resonance imaging (MRI) of the brain including diffusion-weighted imaging (DWI) is reported to have high prognostic accuracy in unconscious post-cardiac arrest (CA) patients. We documented acute MRI findings in the brain in both conscious and unconscious post-CA patients treated with target temperature management (TTM) at 32-34°C for 24 h as well as the relation to patients' neurological outcome after 6 months. METHODS: A prospective observational study with MRI was performed regardless of the level of consciousness in post-CA patients treated with TTM. Neurological outcome was assessed using the Cerebral Performance Categories scale and dichotomized into good and poor outcome. RESULTS: Forty-six patients underwent MRI at 3-5 days post-CA. Patients with good outcome had minor, mainly frontal and parietal, lesions. Acute hypoxic/ischemic lesions on MRI including DWI were more common in patients with poor outcome (P = 0.007). These lesions affected mostly gray matter (deep or cortical), with or without involvement of the underlying white matter. Lesions in the occipital and temporal lobes, deep gray matter and cerebellum showed strongest associations with poor outcome. Decreased apparent diffusion coefficient, was more common in patients with poor outcome. CONCLUSIONS: Extensive acute hypoxic/ischemic MRI lesions in the cortical regions, deep gray matter and cerebellum detected by visual analysis as well as low apparent diffusion coefficient values from quantitative measurements were associated with poor outcome. Patients with good outcome had minor hypoxic/ischemic changes, mainly in the frontal and parietal lobes.

Recombinant human growth hormone improves cognitive capacity in a pain patient exposed to chronic opioids.

During recent decades, the increasing use of opioids for chronic non-cancer pain has raised concerns regarding tolerance, addiction, and importantly cognitive dysfunction. Current research suggests that the somatotrophic axis could play an important role in cognitive function. Administration of growth hormone (GH) to GH-deficient humans and experimental animals has been shown to result in significant improvements in cognitive capacity. In this report, a patient with cognitive disabilities resulting from chronic treatment with opioids for neuropathic pain received recombinant human growth hormone (rhGH) replacement therapy. A 61-year-old man presented with severe cognitive dysfunction after long-term methadone treatment for intercostal neuralgia and was diagnosed with GH insufficiency by GH releasing hormone-arginine testing. The effect of rhGH replacement therapy on his cognitive capacity and quality of life was investigated. The hippocampal volume was measured using magnetic resonance imaging, and the ratios of the major metabolites were calculated using proton magnetic resonance spectroscopy. Cognitive testing revealed significant improvements in visuospatial cognitive function after rhGH. The hippocampal volume remained unchanged. In the right hippocampus, the N-acetylaspartate/creatine ratio (reflecting nerve cell function) was initially low but increased significantly during rhGH treatment, as did subjective cognitive, physical and emotional functioning. This case report indicates that rhGH replacement therapy could improve cognitive behaviour and well-being, as well as hippocampal metabolism and functioning in opioid-treated patients with chronic pain. The idea that GH could affect brain function and repair disabilities induced by long-term exposure to opioid analgesia is supported.

Assessing tissue damage in multiple sclerosis: a biomarker approach.

OBJECTIVES: Magnetic resonance imaging (MRI) of the brain and spinal cord is the gold standard for assessing disease activity in multiple sclerosis (MS). MRI is an excellent instrument for determination of accumulated damage to the brain and spinal cord, but tells us little about ongoing tissue damage. In this study, biomarkers of oligodendrocyte, axonal and astrocyte injury were related to MRI and clinical findings and used to assess tissue damage in MS. MATERIALS AND METHODS: Cerebrospinal fluid from 44 patients with relapsing-remitting MS, 20 with secondary progressive MS and 15 controls were investigated with ELISA to determine levels of myelin basic protein (MBP), neurofilament light (NFL) and glial fibrillary acidic protein (GFAp). Patients underwent MRI of the brain and spinal cord, and gadolinium enhancing lesions, T1 lesions and T2 lesions were counted. RESULTS: Patients in clinical relapse and patients with nonsymptomatic gadolinium enhancing lesions had high levels of MBP and NFL, indicating ongoing damage to oligodendrocytes and axons. The level of MBP dropped quickly within a week from the onset of a relapse, whereas NFL remained elevated for several weeks and GFAp slowly rose during the course of a relapse. Relapsing-remitting MS patients without gadolinium enhancing lesions had values of MBP, NFL and GFAp similar to controls, while patients with secondary progressive disease had moderately increased values of all biomarkers. CONCLUSIONS: Analysis of MBP, NFL and GFAp provides direct means to measure tissue damage and is a useful addition to our methods for evaluation of MS.

¹H-MR spectroscopy of adult-onset autosomal dominant leukodystrophy with autonomic symptoms.

INTRODUCTION: Adult-onset ADLD with autonomic symptoms is a rare disease with a clinical course somewhat similar to chronic progressive MS but with different imaging findings consisting of extensive white matter changes in the cerebrum and cerebellar peduncles. Patients usually present in the fourth to sixth decade with autonomic symptoms, manifesting later symptoms from the pyramidal tracts and ataxia. Here, we present magnetic resonance spectroscopy (MRS) findings in this disease. METHODS: Fourteen subjects, from two non-related families, with genetic linkage to the disease were studied with magnetic resonance imaging and single-voxel MRS. Clinically, they ranged from asymptomatic to wheelchair-using. Their results were compared to those of age- and sex-matched healthy controls. RESULTS: One MRS was excluded due to suboptimal quality. The remaining 13 subjects manifested characteristic evidence of pathology on MRI, 11 of them exhibited extensive changes. The metabolite concentrations of total Cr, total Cho, and total NAA measured in millimolars, using internal water as a reference, were significantly lower in these 11 subjects compared to controls, and we found linear correlations between all these metabolite levels. When total Cr was used as a reference, we found no difference between subjects and controls. No lactate was detected. CONCLUSION: The decreased metabolite concentrations measured using internal water as a reference are most likely due to increased water content in the tissues, diluting all metabolites to a similar degree. This is also in agreement with the high signal intensity exhibited in the white matter on T2-weighted MR images and with the reported histopathological findings of vacuolated myelin.

Asymmetric development of the hippocampal region is common: a fetal MR imaging study.

BACKGROUND AND PURPOSE: Hippocampal development is poorly understood. This study evaluated the normal development of the hippocampal region during the fetal period by using MR imaging. MATERIALS AND METHODS: MR images of 63 fetuses without intracranial pathology were reviewed independently by 2 radiologists with no knowledge of the fetal GA. Three MR images were performed postmortem and 60 in vivo. The progress of hippocampal inversion was analyzed in coronal sections, and the left and right sides of the hippocampal region were compared in every case. RESULTS: The fetuses in the postmortem examinations were at GWs 17-18 and in the in vivo examinations, at GWs 19-36. The hippocampal sulcus was open, bi- or unilaterally, in 39 fetuses. The oldest was at GW 32. The sulcus was closed at GW 21 at the earliest, unilaterally. In 26/63 fetuses (41%), the deepening or closure of the hippocampal sulcus or hippocampal inversion was asymmetric; in 23 fetuses, the right side developed faster. A shallow collateral sulcus was found earliest at GW 17. A deep collateral sulcus was visible earliest at GW 26 unilaterally, but in all fetuses from GW 31 onward, it was seen bilaterally. The orientation of the collateral sulcus was not related to the GA. CONCLUSIONS: There are wide individual temporal variations in the development and the inversion process of the hippocampal sulcus as well as in the formation of the collateral sulcus. Asymmetric development is common, and in most of the asymmetric cases, the right hippocampus develops faster.

Re-evaluation of the dysequilibrium syndrome.

OBJECTIVES: To re-evaluate middle-aged Swedish patients diagnosed with dysequilibrium syndrome (DES) in childhood and to compare their clinical and neuroimaging features to DES with VLDLR gene mutations (DES-VLDR). MATERIALS AND METHODS: Six patients from five families underwent neurological examination and magnetic resonance imaging (MRI) of the brain. Blood samples from the patients were screened for serum carbohydrate-deficient transferrin (s-CDT; disialotransferrin). The very-low-density lipoprotein receptor (VLDLR) gene was sequenced. RESULTS: Five patients had non-progressive cerebellar ataxia (NPCA), dysarthria and short stature. Mental retardation and strabismus, characteristic for DES-VLDLR, were inconsistent among our patients. None of our patients had VLDLR mutations or MRI findings characteristic of DES-VLDLR. MRI findings were variable from a normal cerebellum to marked cerebellar hypoplasia or atrophy and signal intensity changes. One patient was diagnosed with congenital disorder of glycosylation type 1a (CDG-1a). CONCLUSIONS: DES was originally coined on mainly clinical grounds before MRI and specific genetic tests were available, both of which should be used to arrive at an appropriate diagnosis.

Bilateral and recurrent optic neuritis in multiple sclerosis.

OBJECTIVE: To assess the frequency of bilateral and recurrent optic neuritis (ON) in multiple sclerosis (MS) and to compare these results with epidemiological data of ON in neuromyelitis optica (NMO) and recurrent ON without other signs of disease. METHODS: We identified 472 patients with diagnosis of MS from the Swedish Multiple Sclerosis Register. These patients were evaluated for the presence of ON and whether the ON was the presenting symptom of MS; unilateral or bilateral; monophasic or recurrent. RESULTS: Twenty-one percent presented with ON as their first manifestation of MS. The proportion of patients developing a second attack of ON before demonstration of other manifestations of MS was 5.5% and the frequency of recurrent bilateral ON as the presenting symptom was 3.8%. Only two patients presented with simultaneously appearing bilateral ON corresponding to 0.42%. CONCLUSION: Recurrent ON, whether unilateral or bilateral, is a common presentation of MS. As MS is a much more common disease than NMO, care must be taken when evaluating the work-up of patients with recurrent ON. In some cases repeated MRI and lumbar punctures are warranted to improve diagnostic accuracy, even in the presence of the serological marker NMO-IgG.

Development of the hippocampal region demonstrated by fetal MRI. A preliminary report.

Coronal slices of three fetal MRIs performed post mortem and 37 performed in utero, all without intracranial pathology, was assessed. Progress of the hippocampal inversion was analyzed, the left and right sides were compared and occurrence of the collateral sulcus was revealed. The fetuses in the post mortem examinations were at gestation weeks (GW) 17-18 and in the in utero examinations at GW 19-35. The symmetric development of the hippocampal sulcus was revealed in 26 subjects and asymmetric in 14. The non-ovoid hippocampal formation could be evaluated at GW 24 at earliest and an ovoid hippocampus at GW 29. The collateral sulcus could be recognized at GW 17 in post mortem and at GW 22 in in utero examinations. From GW 29 onwards it was seen in all fetuses and it was symmetric in all but one case. Evaluation of the hippocampi is difficult on fetal MRI, especially in in utero examinations. The hippocampal development is not fulfilled at GW 21 as presumed. There is a wide temporal variation in the development of the hippocampal region, and the developmental process does not progress simultaneously in the right and left side of the same individual.

Clinical, neuroimaging and neurophysiological features in addicts with manganese-ephedrone exposure.

OBJECTIVE: To identify biomarkers supporting the clinical diagnosis of manganism in patients several years after exposure to manganese (Mn). METHODS: Neurophysiological examinations, magnetic resonance imaging (MRI), single-photon emission computed tomography and fluorodeoxyglycose (FDG) positron emission tomography were performed in four former ephedrone addicts with extrapyramidal symptoms. RESULTS: Peripheral nervous system was not affected. No patients had reduced uptake of (123)I Ioflupane in the striatum. MRI signal intensities were slightly changed in the basal ganglia. All patients showed a widespread, but not uniform, pathological pattern of FDG uptake with changes mainly located to the central part of the brain including the basal ganglia and the surrounding white matter. CONCLUSIONS: Presynaptic neurons in the nigrostriatal pathway are intact in Mn-induced parkinsonism after prolonged abstinence from ephedrone. The diagnosis is principally based on clinical signs and the history of drug abuse.

Brain magnetic resonance imaging of siblings from families with two or more children with learning or intellectual disabilities and need for full-time special education.

BACKGROUND: Several factors are involved in determining a child's need for special education (SE). Thus, the value of brain magnetic resonance imaging (MRI) for subjects with learning and intellectual disabilities is uncertain. PURPOSE: To evaluate the usefulness of MRI in the diagnostic process of siblings with learning and intellectual disabilities and need for full-time SE. MATERIAL AND METHODS: Altogether, 119 siblings (mean age 11.9 years) from families in which two or more children attended/had previously attended full-time SE underwent prospective brain MRI. SE grouping included three levels, from specific learning disabilities (level 1) to global intellectual disabilities (level 3). Forty-three controls (level 0, mean age 12.0 years) attended mainstream education groups. Signal intensity and structural abnormalities were analyzed, and areas of the cerebrum, posterior fossa, corpus callosum, vermis and brain stem, and diameters of the corpus callosum were measured. In analyses, all area measurements were calculated in proportion to the total inner skull area. RESULTS: Abnormal finding in MRI was more common for siblings (n=62; 52%) in SE (58% for level 3; 49% for level 2; 35% for level 1) than for controls (n=13; 16%). The siblings showed enlarged supra- (P<0.001) and infratentorial (P=0.015) cerebrospinal fluid (CSF) spaces and mild corpus callosum abnormalities (P=0.003) compared to controls. Siblings in SE had smaller inner skull area than controls (P<0.001). Further, the relative area of the mesencephalon (P=0.027) and the diameter of the body of the corpus callosum (P=0.015) were significantly smaller than in controls. In binary logistic regression analysis, enlarged supratentorial CSF spaces increased the probability of SE (odds ratio 4.2; P=0.023). CONCLUSION: Subjects with learning and intellectual disabilities commonly have more MRI findings than controls. Enlarged supratentorial CSF spaces were a frequent finding in siblings in full-time SE.

MR imaging characteristics and neuropathology of the spinal cord in adult-onset autosomal dominant leukodystrophy with autonomic symptoms.

BACKGROUND AND PURPOSE: MR imaging findings in adult-onset autosomal dominant leukodystrophy (ADLD) with autonomic symptoms have been described in the brain, but no descriptions of MR imaging findings in the spinal cord have been published. Here, we describe MR imaging findings in the spinal cord in adult-onset ADLD with autonomic symptoms and histopathologic investigations of the spinal cord. MATERIALS AND METHODS: Twelve subjects from 2 families with adult-onset ADLD with autonomic symptoms identified by clinical investigation underwent MR imaging examination of the spinal cord. Sagittal and transverse sections were obtained. MR imaging examination of the brain was performed in 11 patients. One of the patients underwent postmortem examination, and the spinal cord was subjected to histopathologic analysis. RESULTS: In all family members with adult-onset ADLD with autonomic symptoms, even in the asymptomatic person, the spinal cord was thin. All examined family members also had a slight general white matter signal intensity (SI) increase in the whole spinal cord, mainly visible in T2-weighted transverse images. The pathologic examination revealed a discrete demyelination in the spinal cord. Brain MR imaging also showed increased T2 SI in the white matter. CONCLUSIONS: The spinal cord is affected in adult-onset ADLD with autonomic symptoms. Findings consist of atrophy and a diffuse T2 SI increase in the white matter. Transverse images are needed to assess these findings. The typical SI changes of the spinal cord are also present in subjects without clinical symptoms of the disease and with very limited changes in the brain.

Statin-treated familial hypercholesterolemia patients with coronary heart disease and pronounced atherosclerosis do not have more brain lesions than healthy controls in later middle age.

BACKGROUND: Clinically silent brain lesions detected with magnetic resonance imaging (MRI) are associated with increased risk for stroke, while stroke risk is controversial in familial hypercholesterolemia (FH). PURPOSE: To determine whether the occurrence and size of clinically silent brain lesions in FH patients with coronary heart disease (CHD) is higher than in neurologically healthy controls without CHD. MATERIAL AND METHODS: Brain MRI (1.5T) was performed on 19 DNA-test-verified FH patients with CHD and on 29 cardiovascularly and neurologically healthy controls, all aged 48 to 64 years. All patients were on cardiovascular medication. Intracranial arteries were evaluated by MR angiography. Infarcts, including lacunas, and white matter T2 hyperintensities (WMHI), considered as signs of small vessel disease, were recorded. A venous blood sample was obtained for assessment of risk factors. Carotid and femoral intima-media thicknesses (IMT), assessed with ultrasound, were indicators of overall atherosclerosis. RESULTS: On intracranial MR angiography, three patients showed irregular walls or narrowed lumens in intracranial carotid arteries. No silent infarcts appeared, and no differences in numbers or sizes of WMHIs between groups were recorded. Patients had greater carotid and femoral IMTs, and a greater number of carotid and femoral plaques. Cholesterol-years score, level of low-density lipoprotein (LDL) cholesterol, and level of high-sensitivity C-reactive protein (hsCRP) of the FH-North Karelia patients were higher than those of the controls, while the level of high-density lipoprotein (HDL) cholesterol in controls was higher. CONCLUSION: FH patients with CHD and adequate cardiovascular risk-factor treatment showed no difference in the amount or size of clinically silent brain lesions compared to controls, despite patients' more severe atherosclerosis.

The earliest MR imaging and proton MR spectroscopy abnormalities in adult-onset Krabbe disease.

BACKGROUND: Adult-onset Krabbe disease is an uncommon form of leukodystrophy. Its magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) manifestations are not well documented. AIM OF THE STUDY: To describe early MR findings in adult-onset Krabbe disease. MATERIALS AND METHODS: A 28-year-old woman who had spastic paraparesis and a 5-year history of gait problems underwent MRI of the brain and cervical spine. Proton MRS was performed at 1.5 T using a short echo time. Metabolites were analyzed in the areas of MR signal abnormalities and normal-appearing brain. Six healthy volunteers were examined as controls. RESULTS: MRI revealed changes in the upper corticospinal tracts, splenium and, minimally, adjacent to the atria of the lateral ventricles. MRS showed decreased creatine, choline, N-acetylaspartate and glutamate and probably elevated lactate in the upper corticospinal tract but not in the normal-appearing frontal lobe. The spinal cord was thin. Laboratory tests verified Krabbe disease. CONCLUSIONS: These results indicate early involvement of the upper corticospinal tract in adult-onset Krabbe disease. The cases reported earlier had imaging changes indicating a more advanced disease or no MR findings. Thinning of the spinal cord is a new finding in Krabbe disease.

MR characteristics and neuropathology in adult-onset autosomal dominant leukodystrophy with autonomic symptoms.

BACKGROUND AND PURPOSE: Three families with adult-onset autosomal dominant leukodystrophy (ADLD) presenting autonomic dysfunction as the first symptom are reported. We describe detailed MR appearances of the brain in 2 new families and neuropathology in 2 patients and compare the findings with those in other adult-onset leukodystrophies. METHODS: Twenty subjects (12 women and 8 men; age range, 29-70 years) from 2 unrelated families with ADLD were examined with MR. Six subjects were asymptomatic. Fourteen had autonomic dysfunction. Eleven of them also had pyramidal signs and ataxia. The brains of 2 autopsied patients were examined histopathologically. RESULTS: Two subjects manifested no neurologic symptoms, signs, or MR pathology. Eighteen subjects displayed radiologic abnormalities ranging from subtle T2 high-signal-intensity changes in the upper corticospinal tract to extensive confluent white matter changes, predominantly in a frontoparietal distribution, along the corticospinal tracts down to the medulla oblongata and in the upper and middle cerebellar peduncles. Periventricular white matter was spared or less affected than the adjacent white matter. Histopathology revealed marked loss of cerebral and cerebellar myelin without signs of inflammation. Oligodendrocytes were relatively spared, the number of axons not markedly decreased, and reactive gliosis was modest. The number of Purkinje cells in the cerebellum was reduced. CONCLUSIONS: Two families with adult-onset ADLD with the disease entity originally reported by Eldridge et al. (N Engl J Med 1984;311:948-53) were described. We propose naming the disease "adult-onset ADLD with autonomic symptoms." The characteristic radiologic findings, combined with the clinical symptoms and mode of inheritance, enable the diagnosis.

Detection and appearance of intraparenchymal haematomas of the brain at 1.5 T with spin-echo, FLAIR and GE sequences: poor relationship to the age of the haematoma.

The specific appearance of blood related to time at T1- and T2-weighted spin-echo (SE) sequences is generally accepted; thus, these sequences are classically used for estimating the age of haematomas. Magnetic resonance imaging at 1.5 T, including T1- and T2-weighted SE fluid-attenuated inversion recovery (FLAIR) and T2*-weighted gradient-echo (GE) sequences, was performed on 82 intraparenchymal haematomas (IPHs) and 15 haemorrhagic infarcts (HIs) in order to analyse the appearance at different stages and with different sequences, and to investigate how reliably the age of hematomas can be estimated. The IPHs had been previously detected by CT, were spontaneous ( n=72) or traumatic ( n=10) in origin and were of different sizes (2 mm to 7 cm) and ages (from 7.5 h to 4 years after acute haemorrhagic event). The age of the lesion was calculated from the moment when clinical symptoms started or the traumatic event occurred. The 15 patients with HIs were patients with ischaemic stroke in whom there was either a suspicion of haemorrhagic transformation on CT, or haemorrhage was detected as an additional finding on MR performed for other indications. Patients with conditions that could affect the SI of blood, such as anticoagulant therapy or severe anaemia, were excluded. The signal intensity pattern of the lesions was analysed and related to their ages without prior knowledge of the clinical data. All lesions were detected with T2*-weighted GE. T1-weighted SE missed 13 haematomas and T2-weighted SE and FLAIR sequences missed five. Haemorrhagic transformation was missed in three infarcts by T1-, T2-weighted SE and FLAIR. The signal pattern on FLAIR was identical to that on T2-weighted SE. For all sequences, a wide variety of signal patterns, without a clear relationship to the age of the haematomas, was observed. There was a poor relationship between the real MR appearance of IPHs and the theoretical appearance on SE sequences. T2*-weighted GE was effective for detecting small bleedings but was not useful for estimating the age of a lesion. The FLAIR does not provide any more information than T2-weighted SE.