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Tethered cord syndrome, usually discovered in childhood, is a developmental abnormality impairing the longitudinal movement of the spinal cord that can be combined with various forms of spinal dysraphism. Adult onset tethered cord syndrome (ATCS) seems not as rare as once thought, however, low susceptibility in adulthood commonly leads to a delay in diagnosis and therapy. We conducted a meticulous literature research to evaluate the clinical presentation, associated malformations, prognostic factors, as well as the benefits and risks of surgical treatment in ATCS patients. The age of patients at onset of symptoms ranged from 18 to 76 years with a mean of 36.5 years, including 184 males and 202 females. In contrast to the pediatric clientele, pain is the predominant symptom in adults, and elicitating mechanisms like trauma, excessive physical training, or degenerative spinal canal stenosis are reported more often. Surgical untethering aims the restoration of craniocaudal mobility of the spinal cord in order to prevent the further progression of symptoms, to restore neurological function, and to improve pain. In our evaluation of literature, pain was the most responsive symptom after surgical untethering (307 of 368 patients). Sensory and motor symptoms also seem to benefit from the surgery, especially if less than 6 months standing and mild. Improvement could be achieved in 43% (144 of 335 patients) for sensory deficits and 58.6% (191 of 326 patients) for motor deficits. Sphincter troubles are less responsive; they show an improvement in 45.6% (141 of 309 patients). Factors reported to be associated with the postoperative deterioration and/or bad outcome are the split cord malformation, lipomyelomeningocele, previous surgery, rapid motor function worsening experienced shortly before the operation, and long delay in diagnosis. The rate of secondary decline and retethering could not be established in our literature research. We report on an additional case of ATCS with the late onset of symptoms at the age of 49; she underwent surgical untethering with neuronavigational guidance. Performing neuronavigational guidance on the basis of multimodal images (computed tomography and magnetic resonance imaging fused with the intraoperative biplanar X-ray) in our patient showed substantial benefit in the surgical orientation within a complex skeletal and neuronal anomaly. [ABSTRACT FROM AUTHOR]

The anterior optic pathways are rarely affected by vascular malformations. In a meticulous literature review, 42 published cases of patients with vascular malformations within optic nerves, chiasma and/or optic tract were found, 30 of them being diagnosed as cavernous haemangiomas. All of them suffered from visual disturbances; in 38.1% previous symptoms had occurred. Surgical treatment resulted in major improvement in most patients. We include a further patient with a cavernous haemangioma of the optic chiasma and left optic tract who presented with an acute defect of the right visual field and severe retro-orbital pain. We succeeded in total excision of the malformation via a neuronavigationally guided approach. In the postoperative course, vision of our patient improved immediately and was found to be completely normal three months after the surgical intervention. Considering our patient and the published cases in the literature, we are of the opinion that microsurgical excision is a safe and efficient treatment for these rare pathologies. [ABSTRACT FROM AUTHOR]

Signal shortening of the motor cortex in T2-weighted MR images is a frequent finding in patients with amyotrophic lateral sclerosis (ALS). The cause of signal shortening in ALS is unknown, although iron deposits have been suggested. To test this hypothesis, we acquired T2*-weighted gradient-echo (GRE) MR images in addition to T2-weighted turbo spin-echo in 69 patients with ALS. Signal shortening in T2-weighted images was found in 31 patients. In T2*-weighted GRE images, only three patients had signal shortening. One patient with additional bifrontal haemorrhage had frontal but no motor cortex signal shortening. Iron deposits do not cause cortical signal shortening in patients with ALS predominantly. Other factors are presumably more important in the generation of cortical T2 shortening in ALS. [ABSTRACT FROM AUTHOR]

Summary Background. Various supratentorial pathological conditions can mimic neoplastic cerebral lesions clinically as well as radiologically. Analysis of the neuroradiological findings, the clinical history, laboratory and other paraclinical data mostly help to narrow down the diagnosis of cerebral pathologies. Sometimes, however, histopathological analysis of the operative specimen after surgery reveals unexpected findings. Patients and findings. In a series of 197 operative procedures performed for glioma surgery between August 2000 and August 2002 we found six distinct cases mimicking supratentorial tumours. Clinicoradiological findings had suggested a neoplastic gliomatous process in all cases. But histopathological examination revealed that in reality one patient had been affected by a stroke, two by hypertensive encephalopathy, and one by radiation necrosis; multiple sclerosis was the underlying pathology in two patients. Interpretation. Conditions which show features similar to those of neoplastic cerebral lesions require advanced magnetic resonance imaging (MRI). The benefit of such sophisticated imaging in relation to the costs is an important issue in this context. Further research in the field of modern image modalities is necessary to evaluate these noninvasive techniques for specification of intracerebral lesions. [ABSTRACT FROM AUTHOR]

The aim of this study was presentation of a whole-body MRI technique with a moving table as a screening tool for bone metastases in patients with breast cancer. Twenty-two patients with breast carcinoma underwent both a planar whole-body bone scintigraphy and whole-body MRI at 1.5 T. The MRI images were acquired with a moving table at six different anatomical positions within a measurement time of 20 min. Coronal images were acquired using a short-tau inversion recovery sequence, accomplished by an axial T2-weighted turbo-spin-echo sequence through the head, and a T1-weighted opposed-phase sagittal 2D fast low-angle shot sequence covering the whole spine. The MRI findings indicating bone metastases were compared with findings from bone scintigraphy. Metastatic lesions were confirmed by follow-up examinations over 1 year. Twelve patients showed bone metastases. Whole-body MRI was superior to bone scintigraphy in predicting lesion origin with a sensitivity of 92% (bone scintigraphy 83%), a specificity of 90% (scintigraphy 80%) and an accuracy of 91% (scintigraphy 82%). The MRI showed additional findings such as metastases of the lung and liver. Whole-body MRI with moving table technique may be an effective method of total body screening for bone in selected patients with breast carcinoma and a high risk of distant metastases, although with the higher costs of MRI bone scintigraphy must still be considered as the first method for screening patients with breast cancer. [ABSTRACT FROM AUTHOR]

In this paper we introduce a phased-array coil dedicated for MRA of peripheral arteries which covers the upper and lower legs. The structure of this coil includes a solid cabinet with four flexible wings forming a "T." The flexibility of the wings allows adaptation to the individual leg size. There are eight circularly polarized channels, four on each side. This coil is compatible with other surface coils. For MRA of peripheral arteries, it is combined with the body phased-array coil and the spine array coil which cover the lower abdomen and the pelvis. We examined six patients using this coil combination. The image quality, the signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of these examinations were compared with that of peripheral MRA examinations obtained with the body resonator. Image quality with the array coil was considerably improved in comparison with the body resonator examinations. The SNR and CNR increased approximately 100%. The handling of this coil was very quick and simple, similar to the procedure with other surface coils. The use of dedicated phased-array coils for peripheral MRA may be an important step toward the establishment of MR digital subtraction angiography (DSA) as a non-invasive alternative to intra-arterial DSA in the visualization of peripheral arteries. Its potential has to be evaluated in future studies. [ABSTRACT FROM AUTHOR]

Our purpose was to evaluate a dedicated head and neck coil for demonstration of supra-aortic arteries with optimised magnetic resonance angiography techniques. We performed 47 examinations with a 1.5-T system. We used coronal 3D fast imaging with steady precession (FISP), axial 3D tilted optimised nonsaturating excitation (TONE) and 2D fast low-angle shot (FLASH) for the carotid bifurcation, axial 3D TONE with or without magnetisation transfer (MT) for intracranial arteries, and axial 3D FISP or TONE for the aortic arch. Evaluation included visual assessment of image quality and grading of stenoses near the carotid bifurcation; digital subtraction angiography was used as the reference method. Axial 3D TONE gave superior image quality at the carotid bifurcation, MT-TONE intracranially, and 3D FISP for the aortic arch vessels. Nevertheless, sensitivity and specificity for detection of significant stenoses were similar with coronal 3D FISP (96.3 %, 94.0 %), axial 3D TONE (92.6 %, 92.5 %) and axial 2D FLASH (96.3 %, 86.6 %). Image quality at the aortic arch needs further improvement. [ABSTRACT FROM AUTHOR]

Our aim was to evaluate the diagnostic reliability of turbo spin-echo (TSE) sequences compared to a conventional dual-echo spin-echo (SE) sequence in routine brain MRI at 1.0 T. The following demands were made on TSE sequences: acquisition time-reduction of at least 50% and true proton density (PD) contrast (lowsignal cerebrospinal fluid). A conventional spin-echo and two single-echo TSE sequences were used in 150 patients, a dual-echo TSE sequence in addition in 50 patients. Demonstration of most anatomical structures and disorders was equivalent with TSE and SE sequences. Advantages of TSE were reduced flow artefacts on T2-weighted images, better lesion contrast on PD-weighted TSE images (especially in the dual-echosequence) and acquisition time reduction to about 5 min (single-echo TSE) and 3∶35 min (dual-echo TSE). Disadvantages of TSE were: reduced contrast of tron-containing substances such as heamosiderin and of areas of calcification. By virtue of the shorter acquisition time and diagnostic reliability dual-echo TSE proved the best sequence. If it is used with only one acquisition-whereby image quality but not diagnostic reliability is slightly decreased - acquisition time can be further reduced to 1∶48 min. Application of a susceptibility-sensitive gradient-echo sequence, such as FLASH, compensates for the disadvantages mentioned above. [ABSTRACT FROM AUTHOR]

Insulin-dependent diabetes mellitus (IDDM) is associated with autoantibodies to several pancreatic islet antigens. We have described an assay in which autoantibodies displace a radiolabelled monoclonal anti-islet antibody. Sera from 87 % of 429 children at time of diagnosis of IDDM were positive, while sera from control groups had much lower prevalences (1.3-19 %). Sera from 41.9 % of diabetic subjects remained positive after 20 years duration of IDDM. Sera from 23.6 % of parents and 37.9 % of non-diabetic siblings were positive. Twenty relatives who subsequently developed IDDM had the same prevalence of the antibodies (85 %) as did the patients at time of diagnosis. These findings confirm that the autoantibodies detected by monoclonal antibody (mAb) 1A2 are common at the onset of IDDM and their presence prior to the onset of hyperglycaemia suggests that this method may be useful in screening non-diabetic populations. The high prevalence of antibodies in relatives reduces the efficacy for diabetes prediction, but suggests either that generation of these antibodies is an autosomal dominant trait, or that the antigen detected by these antibodies is cross-reactive with a common environmental antigen. Differentiation between these hypotheses will await the identification of the specific islet-cell antigen detected by mAb 1A2. [Diabetologia (1996) 39: 1365-1371] [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a frequent transient or rare permanent complication of pregnancy. The role of autoimmune phenomena in this gestational form of diabetes is incompletely understood. We have examined sera from 312 pregnant women who had abnormal glucose tolerance (based on a screening examination during the second trimester) for the presence of islet cell surface antibodies or insulin autoantibodies. Fifty-eight of these women were lost to follow-up. Of the remaining subjects, 144 (57.1%) had gestational diabetes diagnosed by formal glucose tolerance testing and the others (42.9%) were normal. Sixty percent of the women with gestational diabetes eventually required insulin to control their blood glucose during pregnancy. One serum from the non-diabetic women was positive for insulin antibodies (0.9%);8 of the sera from the patients with gestational diabetes were positive (5.6%). Subsequent analysis revealed that all nine of the women whose sera were positive for insulin autoantibodies had been treated with insulin previously. Islet cell surface antibodies were strongly correlated with gestational diabetes. Forty-five of 144 gestational diabetic sera were positive (31.3%) whereas only 9 of 108 suspect control sera (8.3%) and 7 of 60 unknown sera (11.7%) were positive. These data suggest that a high percentage of pregnant women who screen positive for glucose intolerance have serological evidence of an autoimmune response against the pancreatic islets, in spite of the state of relative immune tolerance during pregnancy. These data suggest that autoimmune phenomena may play a role in gestational diabetes and that the presence of islet cell antibodies can predict insulin-requiring gestational diabetes. [ABSTRACT FROM AUTHOR]

Anti-B cell auto-immunity may play a role in the pathogenesis of diabetes in mice resulting from multiple subdiabetogenic doses of the pancreatic B cell toxin, streptozotocin. In the present study we have investigated the cytotoxic anti-B cell response in these mice. A major role for B lymphocytes, macrophages, or their products in the cytotoxic response originally detected in vitro was eliminated by passing splenocytes from the mice treated with multiple subdiabetogenic doses of streptozotocin over a nylon wool column. The removal of the adherent cells enhanced the cytotoxicity against a rat insulinoma cell line in vitro by that expected due to enrichment of T-lymphocytes by approximately twofold. The induction of diabetes after multiple subdiabetogenic doses of streptozotocin is strain dependent. Mice of five strains were immunized with rat insulinoma cells, but only splenocytes from the two strains susceptible to multiple subdiabetogenic doses of streptozotocin demonstrated a significant cytotoxic response against the rat insulinoma cells in vitro. Mice pre-immunized with either the rat insulinoma cells or with syngeneic islets labelled in vitro with the hapten trinitrophenol developed hyperglycaemia more rapidly than control mice after multiple subdiabetogenic doses of streptozotocin. In the latter experiment the control mice immunized with complete Freund's adjuvant alone also became hyperglycaemic after a modified multiple subdiabetogenic dose of streptozotocin that did not cause diabetes in non-immunized mice. In mice pre-treated with either adjuvant or cyclophosphamide and then given a modified multiple subdiabetogenic dose of streptozotocin (35 mg/kg × 5 rather than 40 mg/ kg) the degree of hyperglycaemia was reduced and there was no protective effect of cyclophosphamide. However, the mice pre-treated with adjuvant again developed hyperglycaemia more rapidly and to a much higher level than did the mice given multiple subdiabetogenic doses of streptozotocin only. These additional data further support the hypothesis that B-cell destruction after multiple subdiabetogenic doses of streptozotocin results from triggering of an immune response against these insulin-producing cells. [ABSTRACT FROM AUTHOR]

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The aim of this study was to determine whether low-field magnetic resonance (MR) imaging can safely and accurately depict inflammatory changes in patients with anal dynamic graciloplasty, in whom high-field MR imaging is contraindicated and ultrasonography and computed tomography are inadequate. A 0.2-T field-strength MR examination was performed in six patients with anal dynamic graciloplasty malfunction in whom reoperation was contemplated. The following sequences were applied: T 2-weighted turbo spinecho with fat saturation, T 1-weighted conventional spin-echo, and contrastenhanced T 1-weighted conventional spin-echo with fat saturation. Results indicated that none of the patients experienced relevant discomfort, pacemaker malfunction, or electrode dislocation with low-field MR imaging. Inflammatory pelvic changes were visualized in four patients and atrophy of the transposed gracilis muscle in another. Surgery was thus avoided in the four, who underwent conservative treatment for their pelvic inflammation. It was concluded that these prelininary results demonstrate the feasibility of MR imaging with a low field strength in patients with anal dynamic graciloplasty. In such patients, in whom diagnostic imaging had been problematic, the potential for safe and accurate visualization will be a boon to treatment planning. [ABSTRACT FROM AUTHOR]

An increased prevalence of Type 1 (insulin-dependent) diabetes has been reported in patients with congenital rubella. Rubella virus multiplies in the pancreas, and we have hypothesized that studies of children with congenital rubella would be of great importance in following the development of Type 1 diabetes in a defined, susceptible population. Two hundred and forty-one children with congenital rubella (mean age 17.4±0.3 years; 65% black and hispanic) have been evaluated, 30 of whom already have diabetes and 17 of whom have borderline glucose tolerance. In these latter two groups, HLA-DR3 is significantly increased and HLA-DR2 significantly decreased. Pancreatic islet cell cytotoxic surface antibodies are found in 20% of the total congenital rubella population, including in more than 50% in the time period before they develop diabetes and are not related to any specific HLA type. In addition, anti-microsomal and anti-thyroglobulin antibodies are found in 34% of this population. The data demonstrate that Type 1 diabetes developing in congenital rubella patients has the genetic and immunological features of classical Type 1 diabetes, namely the presence of HLA-DR3, the absence of HLA-DR2, islet cell surface antibodies before decompensation and an increased prevalence of anti-thyroid antibodies. Patients with non-diabetic congenital rubella represent an easily identifiable group in whom other immunological factors associated with Type 1 diabetes can be elucidated and possibly modified. [ABSTRACT FROM AUTHOR]