Potentialities of magnetic resonance imaging in the complex of prenatal radiation diagnosis of fetal malformations

The purpose of the study was to investigate the potentialities of magnetic resonance imaging (MRI) in the complex of prenatal radiation diagnosis of fetal malformations. Twenty-eight female patients with suspected fetal malformations were examined. Ultrasound study was supplemented by MRI according to a specially developed protocol. Various fetal CNS malformations were diagnosed. These included the Arnold-Chiari syndrome, the Dandy-Walker syndrome, occlusive hydrocephaly, lobular holoprosencephaly, porencephaly, diaphragmatic hernias, anomalies of the abdomen and retroperitoneal space, as well as anomalies of facial structures, including median clefts, and dacryocystocele. The use of MRI in the complex prenatal radiation diagnosis makes it possible to visualize fetal malformation more clearly, contributes to the more adequate prediction of the outcome of pregnancy and to the choice of a management policy for a female patient.     

Secretor state and renal scarring in girls with recurrent pyelonephritis

The non-secretor phenotype was significantly associated with the occurrence of renal scarring among patients with recurrent pyelonephritis. Girls (n = 77) with recurrent pyelonephritis were followed from the first known episode of infection for up to twelve years with repeated radiological investigations. They were divided into two categories: those with renal scars (n = 35) and those who did not develop scars (n = 42). There was a significant over-representation of non-secretors among the patients with scarring, (14/35, 40%) compared to the healthy controls (21.8%, P less than 0.05). The frequency of non-secretors among the girls who did not develop scars in spite of repeated episodes of acute pyelonephritis was not significantly different from the healthy controls (9/42, 21% n.s.). This study provides a basis for analysis of the influence of secretor state on host-parasite interaction in the urinary tract.     

Secretor state and renal scarring in girls with recurrent pyelonephritis

Abstract The non-secretor phenotype was significantly associated with the occurrence of renal scarring among patients with recurrent pyelonephritis. Girls ( n = 77) with recurrent pyelonephritis were followed from the first known episode of infection for up to twelve years with repeated radiological investigations. They were divided into two categories: those with renal scars ( n = 35) and those who did not develop scars ( n = 42). There was a significant over-representation of non-secretors among the patients with scarring, (14/35, 40%) compared to the healthy controls (21.8%, P < 0.05). The frequency of non-secretors among the girls who did not develop scars in spite of repeated episodes of acute pyelonephritis was not significantly different from the healthy controls (9/42, 21%, n.s.). This study provides a basis for analysis of the influence of secretor state on host-parasite interaction in the urinary tract.     

The role of magnetic resonance imaging in the management of vascular malformations of the trunk and extremities

Vascular malformations can usually be diagnosed on clinical grounds. They have a well-defined appearance on magnetic resonance imaging, which can effectively determine their tissue and flow characteristics. However, the role of cross-sectional imaging in the management of vascular malformations is not well defined. Most reviews suggest that magnetic resonance imaging should be reserved for cases in which the extent of the lesion cannot be estimated on physical examination. However, to date no group has compared the accuracy of physical examination alone to that of magnetic resonance imaging in determining this extent. A review was performed of all the patients evaluated for vascular malformations at the New York University Trunk and Extremity Vascular Anomalies Conference between July of 1994 and August of 1999. Patients who underwent magnetic resonance evaluation at other institutions and whose images were not available for review were excluded. All study patients either underwent magnetic resonance imaging examination at New York University Medical Center or had outside films reviewed at the center. The physical examination findings were compared with the magnetic resonance findings and the surgeon and radiologist made a joint decision about whether there was a correlation between the magnetic resonance and physical examination findings. Fifty-eight patients met the study criteria, 44 (76 percent) of whom were found to have more extensive disease on magnetic resonance examination than appreciated on physical examination. Of the 51 patients with low-flow vascular malformations (venous vascular malformations, lymphatic malformations, and capillary malformations), 39 (76 percent) had more extensive disease on magnetic resonance examination than on physical examination. Of the seven patients with high-flow arteriovenous malformations, five had more extensive disease on magnetic resonance. In all of the 44 patients whose magnetic resonance imaging findings did not correlate with those of the physical examination, therapeutic decision making was affected. Contrary to the conventional wisdom of published reviews, physical examination findings significantly underestimated the extent of vascular malformations in the majority of cases. Magnetic resonance imaging should be performed in all patients with vascular malformations of the trunk and extremities before therapy is planned. In an age when physicians are asked to justify their decisions, especially where the use of expensive diagnostic modalities is concerned, the situations in which these tests are indispensable must be clearly defined or else patients will be denied access to them.     

Syndrome of renal, genital and feet malformations.

We report a 2 months old girl affected by renal hypoplasia, genital abnormalities, syndactyly and a pattern of minor anomalies. Although the pattern of malformations overlaps the Townwes-Brock syndrome and that reported by Green et al in 1996, differential diagnosis was made with other several syndromes including acral and renal anomalies.     

Use of magnetic resonance imaging for the evaluation of vascular malformations of the lower extremity

Vascular malformations are anatomically subdivided according to the predominant channel anomaly into either capillary, arterial, venous, lymphatic, or combinations. They can be further subdivided into high- or low-flow malformations. Any lesion that has an arterial component is considered a high-flow malformation. Once the diagnosis of a vascular malformation is made, it is of paramount importance to define not only the flow characteristics but also the full range of extension, because the prognosis and appropriate treatment vary substantially for each type of anomaly. The two most useful noninvasive imaging techniques for assessing vascular malformations are magnetic resonance imaging (MRI) and ultrasonography. The aim of this review is to give surgeons involved in treating patients with vascular malformations an opportunity to gain some background on MRI scans when assessing vascular malformations. Although MRI is a powerful modality for assessing vascular malformations, we will also discuss some of the limitations of MRI. We further suggest a diagnostic flow chart developed on the basis of MRI features designed to help determine the composition of a vascular birthmark when intervention is anticipated.     

Contribution of magnetic resonance imaging to the knowledge of CNS malformations related to chromosomal aberrations

Summary Twelve patients presenting with various clinicopathological syndromes related to chromosomal diseases have been evaluated using magnetic resonance imaging. They include patients with trisomy 21, trisomy 18, trisomy 13, 4p-syndrome, 5p-syndrome, and 7p-syndrome. In all these patients karyotype studies were performed demonstrating the chromosomal aberrations. All patients were examined using magnetic resonance imaging to evaluate the head and neck malformations which may be specifically associated with their chromosomal anomaly. We were particularly interested in brain abnormalities and the morphological findings correlated with some pathologic anatomical findings. A review of the literature on neuropathological data is reported and compared with the in vivo anatomical results obtained using this highly anatomical non-ionising and non-invasive investigative procedure. Particular interest is paid to trisomy 21 in which all recognizable stereotyped morphological skull and brain malformations are depicted with magnetic resonance and some other malformations demonstrated such as the excessive forward bending and ascension of the brainstem which correlated well with a simian cephalic organization.     

Visualizing myeloarchitecture with magnetic resonance imaging in primates

The pattern of myelination over the cerebral cortex, termed myeloarchitecture, is an established and often-used feature to visualize cortical organization with histology in a variety of primate species. In this paper, we use in vivo magnetic resonance imaging (MRI) and advanced image processing using surface rendering to visualize and characterize myeloarchitecture in a small nonhuman primate, the common marmoset (Callithrix jacchus). Through images made in four female adult marmosets, we produce a representative 3D map of marmoset myeloarchitecture and flatten and annotate this map to show the location and extent of a variety of major areas of the cortex, including the primary visual, auditory, and somatosensory areas. By treating our MRI data as a surface, we can measure the surface area of cortical areas, and we present these measurements here to summarize cortical organization in the marmoset.     

Role of magnetic resonance imaging in the detection of chondral and osteochondral lesions in chronic juvenile arthritis

Chronic juvenile arthritis (CJA) is the most common inflammatory disease of joints in children. There are numerous studies showing the limited informative value of X-ray in the evaluation of CJA progression. Contrast-enhanced magnetic resonance imaging (MRI) using intravenous gadolinium is currently in the foreground in diagnosing arthritis in children, in infants in particular. Knee joints are most frequently afflicted in CJA, showing significant manifestations of the disease. The purpose of the study was to describe the patterns of changes in the nonossified epiphyseal and articular cartilages in the distal epiphyses of femurs in the knee joints of patients with manifestations of chronic juvenile arthritis and to define the role of contrast-enhanced MRI in evaluating the epiphyseal changes in this disease. Sixty-nine patients aged 1.5-14 years who have clinical laboratory and ultrasound signs of CJA lasting 6 months to 5 years underwent contrast-enhanced MRI for the evaluation of changes in the articular and nonossified epiphyseal cartilages. Intravenous contrast enhancement identified several specific features and patterns of epiphyseal changes: subchondral hyperemia of epiphyses and recorded thickened epiphyseal chondral vascular channels, chondral and osteochondral erosions as manifestations of changes in the growing epiphyseal cartilage and articular one in children with chronic arthritis. Thus, contrast-enhanced MRI allows differentiation of different patterns of epiphyseal changes in CJA.     

Potentialities of new radiation technologies (ultrasonography, computed tomography, magnetic resonance imaging) in the diagnosis of endocrine diseases

In the paper providing the data available in the literature and many years' experience gained by the Department of the Moscow Regional Clinical Research Institute, the authors describe the potentialities of the currently available radiation techniques in the diagnosis of surgical endocrine diseases. The incidence of various organ dysfunctions is presented. The authors also consider the introscopic symptoms of various endocrinopathies and outline the common specific features of the ultrasound, computed tomographic, and magnetic resonance imaging pattern of individual masses (including adipose tissue cysts and tumors). Emphasis is laid on the leading role of ultrasonography (USG) in the diagnosis of thyroid and parathyroid diseases and on the priorities of computed tomography (CT) and magnetic resonance imaging (MRI) in visualIzing the abnormal thymus, mediastinally ectopic glands, and pituitary tumors. The capacities of each technique in the diagnosis of endocrine space lesions of the pancreas and adrenals are defined. The increase in the frequency of endocrine abnormalities accidentally identified at USG, CT, and MRI, which is noted in the paper, fosters the development of new trends in endocrinology and points to the need for screening surveys (particularly patients who live in poor environmental areas).     

Combination of diffusion tensor and functional magnetic resonance imaging during recovery from the vegetative state

Background  

The rate of recovery from the vegetative state (VS) is low. Currently, little is known of the mechanisms and cerebral changes that accompany those relatively rare cases of good recovery. Here, we combined functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) to study the evolution of one VS patient at one month post-ictus and again twelve months later when he had recovered consciousness.     

Three-dimensional imaging of the mouse neurovasculature with magnetic resonance microscopy

Knowledge of the three-dimensional (3D) architecture of blood vessels in the brain is crucial because the progression of various neuropathologies ranging from Alzheimer's disease to brain tumors involves anomalous blood vessels. The challenges in obtaining such data from patients, in conjunction with development of mouse models of neuropathology, have made the murine brain indispensable for investigating disease induced neurovascular changes. Here we describe a novel method for whole brain 3D mapping of murine neurovasculature using magnetic resonance microscopy (μMRI). This approach preserves the vascular and white matter tract architecture, and can be combined with complementary MRI contrast mechanisms such as diffusion tensor imaging (DTI) to examine the interplay between the vasculature and white matter reorganization that often characterizes neuropathologies. Following validation with micro computed tomography (μCT) and optical microscopy, we demonstrate the utility of this method by: (i) combined 3D imaging of angiogenesis and white matter reorganization in both, invasive and non-invasive brain tumor models; (ii) characterizing the morphological heterogeneity of the vascular phenotype in the murine brain; and (iii) conducting multi-scale imaging of brain tumor angiogenesis, wherein we directly compared in vivo MRI blood volume measurements with ex vivo vasculature data.     

Comparative ultrasound and magnetic resonance diagnosis of fetal CNS malformations

The study was undertaken to optimize the diagnosis of fetal CNS and facial malformations, by using a complex of ultrasound (US) and magnetic resonance imaging (MRI) studies. A hundred and forty-four fetuses with suspected CNS and facial malformations were examined. The US study conducted by a specially developed protocol was supplemented by MRI (48 fetuses) also made by a specially developed protocol. Various fetal CNS malformations, such as neural tube defects, congenital endbrain malformations, cystic lesions, tumors, ventricular complex anomalies, defects of the face and eyes, multiple defects, including CNS and facial anomalies, were detected. With MRI, the diagnosis was changed in 33% of cases. The application of a complex of US and MRI studies enhances the efficiency of diagnosis of congenital CNS and facial malformations in the fetus. MRI in the diagnosis of fetal CNS and facial malformations has a number of advantages and should be used if there is some difficulty in establishing a diagnosis when an US study is performed.     

Use of magnetic resonance imaging in the study of goat mammary glands in vivo

A technique is described for the in-vivo determination of mammary gland size and gross composition in goats by using nuclear magnetic resonance imaging (MRI). The volume of test objects determined with MRI had an error of +0.4 +/- 1.6% of the actual volume. In lactating goats the in-vivo MRI estimate of mammary parenchymal volume was significantly greater than, but highly significantly correlated with, the weight of parenchyma determined post mortem (for the whole udder, r = 0.88, P less than 0.001; for individual glands, r = 0.85, P less than 0.001). MRI-determined estimates of the volume of fluid within the mammary gland were within 1.2% of the volume of milk removed from the udders after imaging. The spin-lattice (T1) relaxation time of the whole udder correlated closely with the volume of fluid within the udder. The T1 relaxation time of parenchymal tissue measured in vivo did not differ significantly from that determined immediately after post-mortem excision.     

Adipose tissue magnetic resonance imaging in the newborn

Infancy is a period of rapid adipose tissue accumulation, and influences during early development are plausible determinants of altered adiposity. The distribution, as well as the quantity of adipose tissue, is a marker of health and disease. Previous methods for the assessment of body composition in infants have been indirect and thus unable to determine adipose quantity reliably, nor assess adipose tissue distribution. Adipose tissue magnetic resonance imaging is direct, non-invasive, radiation free and suitable for serial examinations in infancy. Adipose tissue depots are quantified individually and summated to provide an accurate measure of depot-specific and total adiposity. We have adapted this technique for application to newborns and, to date, have imaged over 100 term and preterm infants.     

Application of magnetic resonance imaging in zoology

Magnetic resonance imaging (MRI) is a noninvasive imaging technique that today constitutes one of the main pillars of preclinical and clinical imaging. MRI’s capacity to depict soft tissue in whole specimens ex vivo as well as in vivo, achievable voxel resolutions well below (100 μm)³, and the absence of ionizing radiation have resulted in the broad application of this technique both in human diagnostics and studies involving small animal model organisms. Unfortunately, MRI systems are expensive devices and have so far only sporadically been used to resolve questions in zoology and in particular in zoomorphology. However, the results from two recent studies involving systematic scanning of representative species from a vertebrate group (fishes) as well as an invertebrate taxon (sea urchins) suggest that MRI could in fact be used more widely in zoology. Using novel image data derived from representative species of numerous higher metazoan clades in combination with a comprehensive literature survey, we review and evaluate the potential of MRI for systematic taxon scanning. According to our results, numerous animal groups are suitable for systematic MRI scanning, among them various cnidarian and arthropod taxa, brachiopods, various molluscan taxa, echinoderms, as well as all vertebrate clades. However, various phyla in their entirety cannot be considered suitable for this approach mainly due to their small size (e.g., Kinorhyncha) or their unfavorable shape (e.g., Nematomorpha), while other taxa are prone to produce artifacts associated either with their biology (e.g., Echiura) or their anatomy (e.g., Polyplacophora). In order to initiate further uses of MRI in zoology, we outline the principles underlying various applications of this technique such as the use of contrast agents, in vivo MRI, functional MRI, as well as magnetic resonance spectroscopy. Finally, we discuss how future technical developments might shape the use of MRI for the study of zoological specimens.     

Potentialities of low-field magnetic resonance tomography in the diagnosis and treatment of invasive cancer of cervix uteri

The aim of the study was to evaluate the efficiency of low-field (0.14 T) magnetic resonance imaging (MRI) in the diagnosis and treatment of cancer of the cervix uteri. MATERIALS AND METHODS: Low-field MRI was performed in 39 patients with cancer of the cervix uteri to define the stage of the tumor and to follow up the outcomes of their treatment. Particular emphasis was laid on the determination of the size of the tumor and the presence of parametral invasion and on metastatic lesions of lymph nodes. MRI data were compared with clinical, morphological, and surgical staging results. In detecting the stage of cancer of the cervix uteri, the accuracy of MRI was 72% whereas that of clinical study was 51%. In determining parametral invasion, the accuracy of clinical study and low-field MRI was 71 and 90%, respectively. The sensitivity and specificity of MRI were 83 and 92%, respectively. The anterioposterior tumor size was an important prognostic factor in following up the outcomes of treatment as there was its close association and the incidence of tumor recurrences. The present study has indicated that the high efficiency of low-field MRI in detecting the stage of invasive cancer of cervix uteri makes it the method of choice in planning treatment and monitoring the outcomes of combined radiation therapy.