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At least 1,027 records · Page 57Linked to original sources
PubMed1999

Early diagnosis of the frontal variant of frontotemporal dementia: how sensitive are standard neuroimaging and neuropsychologic tests?

OBJECTIVE: To examine the role of structural (magnetic resonance imaging [MRI]) and functional (single photon emission computed tomography [SPECT]) imaging and neuropsychologic evaluation in the early diagnosis of frontal variant frontotemporal dementia (fvFTD). BACKGROUND: Current criteria for FTD stress the need for neuropsychologic and functional neuroimaging abnormalities, yet caregivers report lengthy histories of behavioral change. It is not known when, in the course of the disease, these investigations become abnormal, because few longitudinal studies have been reported. METHOD: Longitudinal study of two patients with serial neuropsychologic evaluation and MRI and HMPAO-SPECT scanning. RESULTS: Both patients, men aged 49 and 50, had major changes in personality, behavior, and social conduct that progressed over 5 to 6 years in a way that conformed to the clinical picture of fvFTD. There was remarkably little abnormality on neuropsychologic testing, and MRI and HMPAO-SPECT findings initially were normal. Over time, however, abnormalities on SPECT, frontal atrophy on MRI, or a neuropsychologic profile more typical of fvFTD developed in both patients. CONCLUSIONS: Standard neuropsychologic tests and conventional brain imaging techniques (MRI and SPECT) may not be sensitive to the early changes in fvFTD that occur in the ventromedial frontal cortex, and better methods of accurate early detection are required. These findings are relevant to the diagnostic criteria for FTD.

Atrophy↗
PubMed1999

Spinal cord ultrasonography in children with myelomeningocele.

Secondary tethering of the spinal cord in people with myelomeningocele (MMC) is almost universal but there is a relatively low incidence of the secondary tethered cord syndrome (S-TCS). In view of this, we wish to explore the notion that cord pulsation, as demonstrated by ultrasound of the spinal cord, can become an independent measure for increased tension of the spinal cord in patients with MMC. One-hundred and six patients with MMC underwent ultrasonographic examination of their back, a thorough physical examination, and a careful review of their clinical history. Of these patients, 53 had MRI of their back. Cord pulsation was graded and the statistical relation between pulsation and various clinical and MRI findings was analysed. Age and arm span were not correlated with grades of cord pulsation. The absence of cord pulsation correlated with the presence of symptoms but this relation may be explained by MRI findings of certain structural cord malformations and not by tethering per se. Assuming that cord pulsation is a reliable marker for the tension within the spinal cord, the results of our study suggest that overstretching of the cord is not the main cause for the development of the S-TCS.

Adolescent↗
PubMedDate not supplied

[Cognitive function in the obsessive-compulsive disorder associated with cerebral lesions].

INTRODUCTION: Although obsessive-compulsive symptoms are uncommon among patients with neurological diseases, structural neuroimaging (CAT or MRI) disclose focal brain lesions in some patients. However, little is know about the clinical phenomenology of obsessive-compulsive symptoms and the cognitive deficits that occur in neurological conditions. OBJECTIVE: To review the cognitive functioning of patients who develop an obsessive-compulsive disorder (OCD) in association with focal brain lesions. DEVELOPMENT: In the present study, the author review recent studies which suggest that OCD associated with brain lesions is relatively similar to idiopathic or 'functional' OCD (i.e., OCD unassociated with gross brain damage). Idiopathic and acquired forms of OCD are clinically heterogeneous. The content of obsessions and compulsions in acquired OCD depends, at least in part, of the causative lesion, whereas the pattern of cognitive deficits is more homogeneous affecting attention, general intelligence, verbal and visuospatial memory, and executive function. CONCLUSION: It is suggested that the study of different subgroups of patients with acquired OCD would detect differences in the phenomenology of obsessions and compulsions as well as in the pattern of cognitive deficits. Moreover, this approach can improve our understanding about the pathophysiological mechanisms underlying idiopathic OCD.

Brain Diseases↗
PubMedDate not supplied

Distal extremity swelling with pitting edema in psoriatic arthritis: a case-control study.

OBJECTIVE: To evaluate the frequency and the clinical characteristics of distal extremity swelling with pitting edema in patients with psoriatic arthritis (PsA). METHODS: This was a case-control study of consecutive outpatients with PsA (old and new diagnosis) observed over a 3-month period in three secondary referral centers in Italy. As controls we used the two consecutive rheumatic outpatients, excluding those with spondylarthropathies, observed after a PsA patient. The demographic and clinical features were assessed by clinical examination and review of the medical records. RESULTS: A total of 183 patients with PsA and 366 controls were evaluated. Distal extremity swelling with pitting edema was recorded in 39/183 (21%) PsA patients and in 18/366 (4.9%) controls (p < 0.0001). In 8/39 (20%) patients this feature presented as a first, isolated manifestation of PsA, and in 8 others it was associated with other features of PsA at diagnosis. The upper and lower extremities were affected, predominantly asymmetrically, in 40% and 60% of the cases respectively. In patients with pitting edema compared to those without this feature, the frequency of Achilles enthesitis and plantar fasciitis, calculated together, was higher (p < 0.05) and the duration of arthritis was significantly lower (p = 0.02). In 7 patients the clinical evidence of a predominant involvement of tenosynovial structures was confirmed by MRI. CONCLUSION: Upper or lower distal extremity swelling with pitting edema due to tenosynovitis, usually unilateral, is a common feature in PsA patients and may represent the first, isolated manifestation of the disease.

Adult↗
PubMedDate not supplied

[Sportsman hindfoot pain: role of magnetic resonance imaging].

PURPOSE: To assess the outcome of Magnetic Resonance Imaging (MRI) in the diagnosis of sportsman hindfoot pain. MATERIALS AND METHODS: Fortythree professional athletes (31 men, 12 women, age range: 17-37 years) affected by hindfoot pain underwent MRI. Spin echo (SE) T1W, Gradient echo (GE) T2*W, and fat suppression (Short Time Inversion Recovery: STIR) images were acquired with a 0.5 T superconductive unit (Vectra, GE Medical System, Milwaukee, WI, USA). A dedicated extremities transmitter/receiver coil was used. The lesion site, the presence of anatomic variants (os trigonum, Haglund's deformity), and signal intensity changes were evaluated. RESULTS: In all cases MRI allowed the identification of the cause of the hindfoot pain, in relation to soft tissue (bursae, synovial or nervous structures), bone and articular diseases. Particularly, as regards soft tissue diseases, tendinous abnormalities and inflammatory bursal involvement were frequently found (77% of cases). Bone diseases (22% of cases with posterior talalgia alone), mostly involved the heel (60%), whereas cartilagineous diseases were present in 9% of cases. In 60% of cases an intra-articular osseous or cartilagineous displaced fragment coexisted, determinating joint locking during foot flexo-extension movements. In 38% of cases contemporary involvement of different articular structures was observed. DISCUSSION: Both MRI high contrast resolution and multiplanar capabilities allow the complete evaluation of hindfoot region. In our experience sagittal and axial planes were particularly well suited for the diagnosis and the assessment of disease extension. Furthermore, T2W (GET2*) and fat suppression (STIR) images allow high sensitivity even in early disease detection, when hyperemia or fluid collection occur. CONCLUSIONS: According to our results, it seems possible to state that nowadays MRI is the most reliable technique for identifying the causes of hindfoot pain, in order to provide a correct and effective pre-therapeutic planning.

Adolescent↗
PubMed2002

[A case of medial temporal lobe epilepsy associated with occult focal cortical dysplasia in the lateral temporal neocortex].

A 29-year-old male with medial temporal lobe epilepsy(MTLE) was revealed to have "occult" focal cortical dysplasia(FCD) in the lateral temporal neocortex. He had no history of febrile convulsion and developed complex partial seizure at the age of 14 year, which became intractable. Although MRI failed to reveal structural abnormality in the temporal lobe, even retrospectively, the findings of non-invasive preoperative examination, such as video-EEG monitoring and interictal ECD-SPECT and FDG-PET, were consistent with those of the left MTLE. Intraoperative electrocorticography(ECoG) demonstrated almost continuous paroxysmal activities on the anterior part of the inferior temporal gyrus(ITG). Anterior temporal lobectomy(ATL) with hippocampectomy was performed. Histological examination revealed FCD in the small area with 0.8 mm in diameter of the resected ITG. In the ATL without preoperative invasive examination such as chronic subdural electrode recording, intraoperative ECoG recording is mandatory.

Adult↗
PubMed2002

The lateral asymmetry of the human brain studied by volumetric magnetic resonance imaging.

Improvements in in vivo imaging methods have boosted research on brain asymmetry aimed at further establishing putative anatomical substrates for brain functional lateralization and particularly to explain left-hemisphere specialization for language. We analyzed volume asymmetries for major anatomical divisions of the lateral (perisylvian) brain region and their relative white matter content. A total of 100 healthy right-handed subjects were examined with 3D magnetic resonance imaging (MRI). The insular plane was used to limit the lateral brain, and the sylvian fissure and central sulcus to define frontal, parietal, temporal, and temporo-parieto-occipital regions. Results revealed a frontal region showing similar volumes in both hemispheres, a parietal region and a temporal region both larger in the left hemisphere, and a temporo-parieto-occipital region with predominantly right-sided asymmetry. Volume measurements of the parietal, temporal, and temporo-parieto-occipital regions complemented each other and accounted for 58% of planum temporale area variations. All study regions showed significant asymmetry for relative white matter content (percentage of white matter relative to region volume). White matter asymmetry, however, was particularly relevant for the frontal and temporal regions showing a highly frequent left-sided pattern (frontal region, 90%; temporal region, 91% of subjects). Leftward asymmetry in these two regions occurred in both genders, although hemisphere differences were significantly larger in men. Results from this MRI volume analysis of structural asymmetries in the lateral brain region complement data obtained by other methods and suggest a high occurrence of leftward asymmetry for relative white matter content in language-related regions.

Adult↗
PubMed2003

Role of in vivo proton MR spectroscopy in the evaluation of adult brain lesions: our preliminary experience.

CONTEXT: A definite diagnosis and characterization of intracranial mass lesions, based on structural Magnetic Resonance Imaging (MRI) alone may be difficult. In such cases Proton Magnetic Resonance Spectroscopy (1H-MRS) along with other non-invasive techniques represents an advance in the specificity of brain lesion diagnosis. AIMS: The primary aim of this study was to evaluate the extent of the utility of 1H-MRS in adult brain tumors and their differentiation from similar-appearing space-occupying lesions. MATERIAL AND METHODS: MRS studies were performed on 1.5 Tesla whole body MR system using standard imaging head coil. Sixty patients (aged 30-65 years), including 35 males (31-65 years) and 25 females (30-65 years) were studied, along with 25 age-matched healthy volunteers (30-64 years). The Student 't' test was used to statistically analyze the spectroscopic data for significant difference in the metabolite ratios of the lesions from normal brain tissue. RESULTS: The Cho/Cr ratio was significantly raised in low and high-grade glioma and meningioma patients (1.85 +/- 0.36, 3.50 +/- 1.00 and 6.65 +/- 2.83 respectively) (mean +/- standard deviation), as compared with the control group (1.16 +/- 0.18); and NAA/Cr and NAA/Cho ratios were found to be lower than normal values in our study (P<0.01). However, in the non-neoplastic lesions, the Cho/Cr ratios were not statistically significant. The tubercular lesions revealed an average Cho/Cr ratio of 1.24 +/- 0.18, while it was 1.14 +/- 0.07 for infarcts. CONCLUSION: MR Spectroscopy was useful to arrive at a more definitive diagnosis in doubtful intracranial space-occupying lesions with similar morphological imaging patterns.

Adult↗
PubMedDate not supplied

Uniform databases in early arthritis: specific measures to complement classification criteria and indices of clinical change.

Rheumatoid arthritis (RA) is not characterized by a single pathognomonic measure such as blood pressure in hypertension or cholesterol in hyperlipidemia, which can be used in the diagnosis, prognosis, and monitoring of patient status. Measures such as swollen joints and an elevated erythrocyte sedimentation rate are certainly valuable, but many individuals with abnormal values have conditions other than RA, and many people with RA may have favorable values for one or more of these measures. Therefore, the rheumatology community has developed indices of several measures, such as classification criteria, the disease activity score (DAS), and the ACR Core Data Set with 20%, 50% and 70% improvement (ACR 20, ACR 50, ACR 70) to classify and monitor patients with RA. While these indices have greatly advanced clinical research, databases for long-term observations, including those in early RA described in this Supplement, differ in 20-50% of included data, and the software platforms for these databases differ sufficiently to render it difficult to merge the data to compare one data set to another. It has been proposed that a uniform database for early arthritis clinical research could help advance clinical research in early arthritis. One example of such a database, termed a "standard protocol to evaluate rheumatoid arthritis" (SPERA), has been in use for almost two decades in one clinical site, and has proven valuable in a number of ways, including the demonstration of early radiographic damage, development of a 28-joint count, and documentation that patient questionnaire data are correlated significantly with laboratory, joint count and radiographic data, although questionnaire data are the strongest predictors of severe outcomes including work disability and premature mortality. The use of a uniform database in no way precludes the collection of additional data at particular centers including immunogenetic, serologic, or structural magnetic resonance imaging (MRI) data. However, the availability of an infrastructure of standard data in all RA databases would enhance clinical research in early RA.

Adult↗
PubMed2004

[Preliminary study on the functional localization of auditory cortex in the healthy young subjects using magnetic source imaging].

OBJECTIVE: To evaluate the value of magnetic source imaging (MSI) in the functional localization of the primary auditory cortex. METHODS: The M100 waves of cortical auditory evoked magnetic fields (AEFs) evoked by 0.5, 1, 2, 4 and 8 kHz pure tones in 5 subjects and by 2 kHz pure tones in 25 healthy young subjects were measured respectively (16 males and 14 females, with the age from 20 to 32 years old) using a whole head 306 channel magnetoencephalography (MEG) system. The MSI obtained by superimposing functional MEG data on structural magnetic resonance image (MRI) was used to localize the M100 sources on the auditory cortex. RESULTS: The M100 waves of AEFs were clear and replicable in both hemispheres. The M100 sources were localized on the bilateral transverse temporal gyri in all 30 subjects. The localization of M100 on transverse temporal gyri varied with the changes of stimulus frequency. The localization of primary auditory cortex was asymmetrical between bilateral hemispheres, and the left hemisphere M100 dipoles were significantly posterior compared to the right M100 dipoles. The M100 responses appeared significantly earlier to the contralateral stimuli than that to the ipsilateral stimuli in both hemispheres. The dipole positions of M100 were independent of the side of the stimuli. CONCLUSIONS: The functional localization of the primary auditory cortex could be determined precisely by magnetic source imaging (MSI) with high spatiotemporal resolution. MSI would hold great promise as a noninvasive tool for the fundamental and clinical research in otology.

Adult↗
PubMed2004

Magnetic resonance imaging of the brain in epileptic pediatric patients: review of the experience in Ramathibodi Hospital.

OBJECTIVE: To review a series of epileptic children referred for MR imaging and correlate the structural abnormalities from the MRI findings with clinical data and EEG. MATERIAL AND METHOD: Retrospective review of MRI of the brain performed in children, aged less than 15 years with epilepsy at Ramathibodi Hospital from January 1999 to December 2002 was done. There were 100 children (57 girls, 43 boys) with epilepsy, age range from one month to 14 years, mean 7 years and 5 months. Diagnosis of seizure type and epilepsy were classified according to clinical presentation and EEG. RESULTS: There were 16 children with primary generalized seizure, 79 children with partial or complex partial seizures with or without secondary generalization. The remaining 5 children had a specific syndrome. The most common etiology of all patients was congenital disease, especially cortical dysplasia. Among children with partial with or without generalization, cortical dysplasia was the most common finding (31%). Mesial temporal sclerosis and combined cortical dysplasia with mesial temporal sclerosis were found in 24% and 13.9%, respectively. Most of the disease categories showed significant concordance of the EEG to the MRI findings, except infectious disease. CONCLUSION: The most common etiology of epilepsy in children under 15 years old was cortical dysplasia. For children with partial or complex partial seizure, cortical dysplasia was the most common etiology followed by mesial temporal sclerosis and combined cortical dysplasia with mesial temporal sclerosis, respectively. MRI provides precise etiologic classifications of epilepsy.

Adolescent↗
PubMedDate not supplied

Comprehensive assessment of left ventricular pseudo-aneurysms with magnetic resonance imaging.

In a small number of patients, myocardial infarction, trauma, infection or cardiac surgery are complicated by incomplete wall rupture and pseudo-aneurysm formation. We describe the advances made in the non-invasive assessment of this condition with the introduction of magnetic resonance imaging (MRI) and discuss the value of specific MRI techniques for comprehensive structural and functional cardiac assessment.

Aneurysm, False↗
PubMed2006

[Preliminary study on the functional localization of auditory cortex in auditory pathology patients using magnetoencephalography].

OBJECTIVE: To access the pathological changes of the functional localization of the primary auditory cortex in auditory neuropathy patients using magnetoencephalography (MEG). METHODS: The M100 waves of cortical evoked magnetic fields (AEF) evoked by 0.5, 1, 2, 4, 6, 8 kHz pure tones were measured respectively in 10 auditory neuropathy patients (20 ears) and 15 healthy young subjects (30 ears) using a whole head 306 channel magnetoencephalography (MEG) system. The auditory cortex magnetic source imaging obtained by superimposing functional MEG data on structural magnetic resonance image (MRI). RESULTS: The M100 sources were obtained in all 15 healthy young subjects in all frequency except for 8 kHz in 16 ears. But in auditory neuropathy patients, the ratio of M100 from 0.5 to 6 kHz were 27.5% (11/40), 22.5% (9/40), 7.5% (3/40), 5% (2/40), 5% (2/40) respectively and no any waves in 8 kHz. The evoked ratio of M100 in low frequency was high and that decreased gradually with increasing of evoked pure tone frequency. The M100 latentencies and amplitudes were longer and lower in patient group than that in control group (P < 0.01). CONCLUSIONS: Auditory neuropathy is an audiology disease with pathological lesions from the VIII cranial nerve to auditory cortex. MEG might become an important reference in decision making for therapies.

Adolescent↗
PubMed2006

[Electrode grids are available for the selection of patients with refractory epilepsy for epilepsy surgery].

In 60-85% of patients with refractory epilepsy, surgical excision of that part of the brain that is considered to be responsible for the development of epileptic seizures leads to the disappearance of the attacks. In the Netherlands, 60-70 patients undergo epilepsy surgery every year; this is a small number in comparison to the number of potential candidates. Patients with medically refractory epilepsy without structural damage on the MRI or with a lesion in or near specialised areas of the cortex could also be examined and then treated surgically. It is important that such patients be referred earlier for possible surgical treatment of their epilepsy.

Anticonvulsants↗
PubMed1990

[Two cases of thymic cyst].

We reported two cases of thymic cyst which were accidentally found by chest X ray. On CT, they showed near water low density masses with thin walls, situated in the prevascular space. In the case 2, the septum-like structure was found by MRI, however, it was not clear by CT.

Adult↗
PubMed1989

[Hepatocellular carcinoma--a comparative study of MR imaging and angiography].

We used magnetic resonance imaging (MRI) at 0.2 T and angiography to evaluate hepatocellular carcinoma (HCC) in 43 patients who had not received therapy. Tumor detection rate by MRI was 84%, T2-weighted spin echo imaging being the best detection method, though one case could only be detected by T1-weighted imaging (Inversion Recovery method). The signal intensity of the tumor relative to the surrounding liver parenchyma was studied using MRI, and tumor staining using angiography. Where there was a high signal intensity in the T2-weighted spin echo images there was a corresponding tendency for tumor staining to be marked. MRI demonstrated the inner structure--which resembles random high-intensity threads on a lower-intensity background--of hypervascular tumors. Tumors with capsules appeared with the capsule clearly delineated irrespective of the signal intensity of the tumor itself.

Adult↗
PubMed1995

[Functional anatomy and biomechanics of the ankle joint].

Functional anatomy is fundamental for understanding motion in the ankle joint. Biomechanical studies try to evaluate the forces and torque affecting biological tissue under various conditions and therefore the cause and effects of disorders of joint structures. Conclusions based on this research permit preventive arrangements to reduce force and risk of injury to the joints. Biomechanical models describe the function of joint movements. A knowledge of biomechanical models may affect therapy management of patients with joint disorders. For the radiologist the results of this basic research are of major importance. Knowledge of pathological joint movements allows more accurate diagnosis of complex disorders or injuries of the ankle joint and structural alterations in bony or soft tissue structures, as demonstrated by MRI. In this article, we summarize the results of functional anatomy and biomechanics of the ankle joint reported in the literature.

Ankle Injuries↗
PubMedDate not supplied

Occult dysraphism in adulthood. A series of 24 cases.

The results of a retrospective study of 24 adult patients with occult dysraphism are described. There were 15 males and 9 females, with an average age of 31.1 years. Specific circumstances precipitated symptomatic onset in 67% of patients. Pain, often referred to the anorectal region, was the most common presenting symptom. Bladder and bowel dysfunction were also common findings. The most common tethering lesions were intradural lipoma and a short thickened filum terminale. Myelography revealed the diagnosis of tethered conus in most cases, but the addition of CT and MRI images provided valuable structural details. The surgical outcome was gratifying in relation to pain and sensory-motor deficits but disappointing in the resolution of sphincter disorders. Our conclusion is that symptoms and/or signs of TCS with onset in adult life are not invariably irreversible.

Adult↗