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At least 1,567 records · Page 87Linked to original sources
PubMed2005

Adrenal and renal metastases from follicular thyroid cancer.

Patients with differentiated thyroid cancer may have asymptomatic involvement of renal and/or adrenal gland, particularly if they are elderly and have associated metastases to other organs, which may remain undetected if these patients are not subjected to radioiodine treatment. Our experience also emphasises the role of routine post-radioiodine therapy whole body scan with high degree of clinical suspicion, which may reveal lesions otherwise not discernable in low dose whole body scan. All suspicious lesions should be subjected to structural imaging like ultrasound, CT or MRI for confirmation. In this setting, the role of radioiodine therapy is primarily aimed at palliation that might prolong their survival, probably reduce further spread and thus overall improve the quality of life.

Adenocarcinoma, Follicular↗
PubMed2005

[Neurocognitive assessment in alcohol abuse and dependence: implications for treatment].

The aim of the Neuropsychology applied to the Alcohol Dependence field is the comprehension of the effects of brain dysfunction on cognition and human behavior. It investigates neurocognitive impairments and associates them to structural and functional neuroimaging findings (CT, MRI, PET and SPECT). Acute use of alcohol impairs attention, memory, executive functions and visuospatial skills, while chronic abuse causes neurocognitive deficits in memory, learning, visuospatial functions, psychomotor speed processing, executive functions and decision-making, and may lead to persistent amnesic disorder and alcoholic dementia. Executive Dysfunction related to frontal lobe has direct implications on treatment, by the choosing of strategies and for prognostic evaluation. It is presented an easy tool to screen cognitive impairments, the Frontal Assessment Battery--FAB.15. Neuropsychological Assessment is useful for early detection of impairments and evaluation of their evolution and Cognitive Rehabilitation has a significant role on deficits recovery and psychosocial adjustment of these patients.

Alcoholism↗
PubMed1993

Present and future applications of lasers in neurosurgery.

The applications of laser in both adults and pediatric neurosurgery are being steadily refined today. For many routine tumor removals, contemporary lasers do not add to ultrasonic aspiration or suction resection. However, there are some tumors in which one CO2 laser is invaluable; brain stem astrocytomas, skull base tumors, and intraspinal tumors are examples. Similarly, in resections of spinal lipomas they are useful to vaporize lipomas from the roots. Laser welding of vessels is technically possible but has generally not been useful. Perhaps the most exciting application is a combination of laser energy transfer with stereotactic technology. The MRI can be used to visualize structural changes in cerebral tissue. We have used this technology in 40 rats with gliomas and have been able to demonstrate destruction.

Central Nervous System Neoplasms↗
PubMed1991

[Diagnostic imaging of the prostate].

Modalities for the diagnostic imaging of the prostate are surveyed. Transrectal sonography is thought to be the best method for the purpose, because of its non-invasive nature, fine picture quality, sufficient reproductivity and less expensive cost. Up-to-date utilizations of the method are described, such as diagnostic capability, staging, monitoring, screening and intervention. CT is less effective but MRI is promising to visualize internal structure inside the prostate. Two very new techniques, namely, ultrasonic Doppler color flow mapping and positron emission CT (PET), of which application to the prostate is being investigated originally in our laboratory, are introduced.

Humans↗
PubMed1999

Imaging of autoimmune diseases.

Autoimmune diseases represent a heterogeneous group of pathologies with a wide range of immunological changes and clinical presentations. The clinical onset of the disease commonly occurs when signs and symptoms of target tissue hypofunction appear; complications can also be present. The aim of an imaging diagnostic technique in this context is to correctly evaluate the disease extent and severity for appropriate treatment and to follow up the efficacy of therapy. In addition, identification of subjects at risk and the preclinical diagnosis may allow disease prevention. Ultrasound (US), conventional radiology and computed tomography (CT) are often used for a detailed morphological study of tissues involved; magnetic resonance (MRI) may also demonstrate biochemical and structural tissue changes. Nuclear medicine techniques are known for their sensitivity and specificity and in recent years an expanding field is represented by the development of radiolabelled receptor ligands. New radiopharmaceuticals able to bind in vivo to specific receptors have been introduced allowing the non invasive detection of changes in affected tissues. The relevant criteria to choose different diagnostic approaches in several autoimmune diseases are discussed in this review. In particular the role and contribution of nuclear medicine for the study of autoimmune diseases have been described.

Antibodies, Monoclonal↗
PubMed1999

Distal extremity swelling with pitting edema in psoriatic arthritis: evidence of 2 pathological mechanisms.

Distal extremity swelling with pitting edema due to altered lymphatic drainage has been reported in some patients with psoriatic arthritis (PsA). The edema usually affected the upper limbs in an asymmetric pattern and was resistant to therapy. We describe 2 additional cases. The distal swelling and pitting edema responded promptly and completely to corticosteroids in the first patient but persisted in the second. Lymphoscintigraphy and magnetic resonance imaging (MRI) revealed a predominant tenosynovitis in the hand without lymphedema in the first patient, and impaired lymphatic drainage without tenosynovial sheath involvement in the second. We conclude that 2 different mechanisms, characterized by a different response to therapy, may be associated with the same clinical picture of distal swelling with pitting edema in patients with psoriatic arthritis. Lymphoscintigraphy and MRI are useful in defining the structures involved and in predicting the prognosis.

Adult↗
PubMed1999

Fat in the heart. A feature unique to the human species? Observational reflections on an unsolved problem.

Fat that is well demarcated from underlying muscle is found on the right ventricular free wall and around epicardial coronary vessels. Fat is not present in the left ventricle in normal subjects. In right ventricular dysplasia, fat and fibrosis may massively displace right ventricular myocardial tissue. It is frequently associated with some clusters of fat and fibrosis in the left ventricle. Adipocytes may be also found within fibrous tissue. In this situation it may be associated with inflammatory cellular infiltrates in both ventricles and this is called metaplastic fat. All these findings may be seen and sometimes are associated to a variable degree in the same myocardial specimen. However, fat may be interspersed with right ventricular myocardial fibres but without fibrosis or signs of inflammation. This situation is observed in more than half of the normal hearts and represents an over-looked pathologic condition only observed in the human species. The term "fat dissociation syndrome" is proposed to identify this condition. This new understanding of right ventricular myocardial structure which may be investigated by MRI may have important clinical consequences.

Adipose Tissue↗
PubMed2000

[Retrospective cephalometric analysis for surgically treated obstructive sleep apnea: therapeutic deductions].

PURPOSE OF THE STUDY: The goal of surgical treatment for severe sleep apnea syndrome is to alleviate the upper airway obstruction. The narrowing site must be precisely determined during the preoperative evaluation to ensure success. We suggest that cephalometric analysis using a lateral cephalic radiograph to evaluate bony structures combined with magnetic resonance imaging (MRI) to study soft tissues may achieve this goal. The purpose of this study was to determine the role of two different cephalometric analysis systems for determining surgical strategy and to underline factors predictive of success for different surgical procedures. MATERIALS AND METHOD: We prospectively studied 73 sleep apnea patients. The preoperative evaluation included MRI and two different cephalometric analyses on a lateral cephalic radiograph: Tweed's and Delaire's analyses. Three surgical techniques were performed: mandibular osteotomy and geni tubercule advancement, maxillo-mandibular advancement and tongue base reduction with hypoepiglottoplasty via a cervical approach. RESULTS: Tweed's analysis appeared to underestimate maxillo-mandibular deficiencies compared with Delaire's analysis; the later seemed to be more sensitive. MRI did not prove to be useful in predicting surgical outcome. MRI was non-contributive in our preoperative evaluation. DISCUSSION: We suggest a new surgical strategy using two procedures: maxillo-mandibular advancement and tongue base reduction. Indications are based on the results of two cephalometric analyses (Tweed and Delaire) and the measurement of the oropharyngeal surface.

Adult↗
PubMed2001

Epileptogenic networks: cerebral dysplasias and cerebral ectopias.

There are three areas in which functional imaging may be applied to malformations of cortical development (MCD) that give rise to epilepsy: the localization of epileptic activity; the identification of areas of functional abnormality; the mapping of normal cerebral functions, and how these may be displaced. Single photon emission computerized tomography (SPECT) commonly shows interictal hypoperfusion and ictal hyperperfusion. Positron emission tomography (PET), using (18)F-fluorodeoxyglucose, often shows glucose metabolism in ectopic grey matter and hypometabolism in MCD, compared with normal cortex. Cognitive activation tasks, using PET or fMRI, have shown that malformed cortex may participate in cerebral functions, but also widespread atypical cortical organization. Cognitive activation tasks using fMRI are useful when planning surgical resections close to eloquent cortex. Binding of (11)C-flumazenil to central benzodiazepine receptors (cBZR) is often abnormal in MCD, and in areas of cortex that appear normal on MRI, with increased and decreased binding. MR Spectroscopy also reveals abnormalities that are more extensive than the MRI visible lesion, implying more widespread structural and functional abnormalities. The recording of EEG during fMRI has allowed the latter to be used to localize cerebral areas involved in the generation of interictal epileptiform activity. Electroencephalograph source localization and magneto-encephalography may also prove to be useful in the localization of interictal epileptiform activity, particularly when fMRI data are used to constrain the solutions.

Cerebral Cortex↗
PubMed1992

[Neonatal tuberous sclerosis: report of a case studied by cranial MRI].

We reported longitudinal cranial MRI studies of a neonate with tuberous sclerosis who presented convulsive seizures on the first day after birth. Cortical tubers were not detected on MRI performed at the age of 1 month, but became evident at 18 months after birth. This finding might reflect the pathological difference between the amount of myelin around the cortical tuber and other white matter lesions, which increased with age. A heterotopic islet was shown as partially stratiform appearance on MRI. This result suggests that the structure of the heterotopic islet might be heterogeneous.

Brain↗
PubMed2001

An evaluation of a case of agenesis of the corpus callosum with Rourke's nonverbal learning disorder model.

This article evaluates the case of an 11-year-old male with congenital agenesis of the corpus callosum, against Rourke's NLD models. A comprehensive neuropsychological assessment was completed, and impairments with attention, movement, fine motor and sensory perception, visuo-spatial organization, and verbal memory were identified. Additionally, a volumetric analysis of the magnetic resonance image (MRI) was completed. Although no gross structural abnormalities, beyond agenesis, were present, the possibility of unobservable abnormalities was considered. Many predicted NLD deficits were clearly evidenced in this case, including associated behavioral problems. This study concludes that although Rourke's NLD model is descriptive of many aspects of white matter impairments, it may not account for the full range or severity of deficits that may be observed. In callosal agenesis, children may exhibit verbal learning, auditory attentional, and verbal expressive difficulties.

Clinical Conference↗
PubMed2004

[Neuroanatomy and neurophysiology in schizophrenia].

Advances in neuroimaging and neurophysiological techniques have enabled detailed investigations of the brain pathophysiology of schizophrenia. In this article, we first overviewed neuroanatomical and neurophysiological studies of the superior temporal gyrus and anterior cingulate cortex in patients with schizophrenia, using structural magnetic resonance imaging (s-MRI), MR spectroscopy (MRS), event-related potentials (ERPs) and magnetoencephalography (MEG). Next, we discussed several key points for future research in psychiatric neuroimaging, such as disease specificity, heterogeneity, utility as endophenotype markers, relationship to psychosocial outcome, and application to clinical purposes. Finally, we described important issues, in terms of the infrastructure and system, which need to be improved in clinical psychiatry research in Japan.

Brain↗
PubMed2005

Idiopathic mediastinal fibrosis presenting as mediastinal compression syndrome.

Mediastinal compression syndrome is a commonly seen entity. Mediastinal compression, mostly due to a space-occupying lesion, is distinct and different from mediastinitis/mediastinal fibrosis, which could also lead to superior vena cava syndrome. Idiopathic mediastinal fibrosis should also be considered as differential diagnosis of mediastinal structures with various radiological, CT and MRI and histological features if feasible. Medical therapy is disappointing while surgical cure has limitations. This interesting patient presented as mediastinal compression syndrome, which on investigation was postulated as idiopathic mediastinal fibrosis, as a diagnosis on exclusion of other causes, which is rare, hence is being reported.

Adult↗
PubMed2006

[Danish clinical guidelines for epilepsy].

Danish clinical guidelines provide evidence-based recommendations for the diagnosis, treatment and care of patients with epilepsy. Clinical problems are evaluated by conducting a systematic search for literature followed by critical reading and methodological assessment of the literature found. Recommendations are made based on the evidence. Some of the important recommendations are as follows: A detailed history taken from the individual and an eyewitness is the most important tool in the diagnosis of epilepsy. EEG should be performed to aid diagnosis and classification of suspected epilepsy. MRI should be used to identify structural abnormalities in focal epilepsy unless there is clear evidence of benign focal epilepsy. The choice of antiepileptic drug depends on the type of epilepsy and the tolerability profile of the drug. Newer antiepileptic drugs are in general better tolerated than older drugs, but not more effective. In the case of diagnostic uncertainty or uncontrolled seizures, the patient should be referred to a more specialised department in a timely manner. The specialist service should include a multidisciplinary team. Epilepsy surgery should be considered early in patients with refractory focal epilepsy.

Adult↗
PubMed1988

Positron emission tomography in the investigation of central nervous system disorders.

Positron emission tomography is a noninvasive tomographic technique for measuring regional tissue concentrations of labeled radionuclides in man. Detection of two photons emitted from the annihilation of a positron and an electron is used to reconstruct the distribution of a positron-emitting isotope within an organ. PET provides the capacity to measure quantitatively the local tissue distribution of a variety of radionuclides that are attached to compounds that distribute according to function. Commonly measured functions include local cerebral metabolism using 18F-fluorodeoxyglucose or 11C-deoxyglucose, cerebral blood flow, cerebral oxygen utilization, and cerebral blood volume. Clinical applications of PET are multiple, involving normal and disease states. By demonstrating the metabolic alterations, PET adds another dimension to our understanding of the brain, which up until recently has been based on the structural changes seen on CT and MRI.

Aging↗
PubMedDate not supplied

[Comparing computerized tomography and magnetic resonance in the study of articular pathology of the knee].

The authors present a comparison between the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in the articular pathologies of the knee. CT and MRI were performed in 30 patients who subsequently underwent surgery. CT and MRI results were compared on three bases: technique, definition of normal anatomy, and diagnostic accuracy. CT allowed a standardization of the technique, while MRI was superior in defining normal anatomy--especially in the study of capsulo-ligamentous structures. In all cases the use of both CT and MRI allowed a correct diagnosis, showing the site, extent and gravity of the lesion. CT proved to be superior to MRI in 4 cases, while MRI corrected CT diagnosis in 11 cases; in 15 patients both techniques had the same diagnostic accuracy. Meniscal tears were better identified by CT, while MRI was superior in the detection of ligamentous lesions and in the characterization of PVNS and tendinitis of the patellar tendon. In conclusion, MRI should be performed in selected cases only, or when CT cannot be trusted; on the other hand, it might also be used as a first-choice diagnostic procedure for synovial pathologies and acute lesions of the anterior cruciate ligament.

Adolescent↗
PubMed1995

[A case of basilar artery occlusion caused by vertebrobasilar artery dissection presenting with mild clinical symptoms].

We reported a first case of basilar artery occlusion caused by vertebrobasilar artery dissection presenting with mild clinical symptoms. A 45-year-old female was admitted to our department due to the abrupt onset of pain in her posterior neck and occipital head, and numbness in the right upper and lower extremities. She had no other neurological complaints. Computerized tomography and magnetic resonance imaging (MRI) disclosed no abnormalities in parenchyma, but MRI revealed a linear high intensity structure in front of the medulla oblongata on T1 and T2 weighted images. Cerebral angiogram showed the pearl and string sign from the left vertebral artery to the proximal basilar artery, and showed the basilar artery occlusion, but the basilar artery distal to the occlusion site was perfused sufficiently by the carotid via posterior communicating arteries. We diagnosed it as basilar artery occlusion caused by vertebrobasilar artery dissection, which was confirmed during the operation to prevent a hemorrhage from the aneurysmal dilatation. In this case, collateral good circulation was thought to have contributed to her good clinical course.

Aortic Dissection↗
PubMed1995

[Magnetic resonance of tibiotalar and subtalar joints. Normal anatomy].

Fifty-three ankles of 29 normal volunteers were examined with Magnetic Resonance Imaging (MRI) to improve the anatomical MR knowledge of tibiotalar and subtalar joints. The aim of our study was therefore to assess the visibility of articular cartilages, tendons and ligaments of the ankle and to define the best scan plane for their visualization. MR studies were performed with SE T1-weighted sequences on the sagittal, coronal and axial planes. The visibility of articular cartilages was 70.8% for the tibiotalar joint and 56.3% for the subtalar joint. All ankle tendons and four of the eight ankle ligaments considered in our study were assessed, at least on one of the sagittal, coronal or axial planes, with over 70% visibility. The deltoid ligament was detected in 95% of the cases on coronal images, the anterior and the posterior talofibular ligaments were seen respectively in 82% and in 75% of the cases on axial images, while the interosseous ligament was detected in 87.5% of the cases on sagittal images. Our study assessed both the capabilities and the limitations of MRI in the detection of anatomical structures of the tibiotalar and subtalar joints and defined the best scan plane for their visualization.

Achilles Tendon↗