Low-field MRI in the evaluation of rheumatoid cervical spine. Comparison with neurological findings and routine plain radiography

The usefulness of a low-field magnetic resonance imaging (MRI) instrument in the evaluation of cervical spine abnormalities was studied in 20 patients with rheumatoid arthritis and known anterior atlantoaxial subluxation (AAS) (16 patients) or other cervical spine abnormalities (4 patients). The MRI results were compared with routine plain radiographs and with neurological findings. Three patients had a clinical suspicion of cervical spinal cord compression. This was confirmed by MRI, which additionally detected one more patient with compressive myelopathy. Anterior AAS in MR images was seen in 4 patients, but proper flexion images were not obtained. Atlantoaxial impaction was detected by a recent method of Sakaguchi-Kauppi in 16 patients as compared to 9 patients by the McGregor method and 4 patients by MRI. Most of the clinically important consequences of rheumatoid cervical spine are seen with a low-field MR imager, but detailed bony changes and precise measurements are better evaluated with plain X-rays.     

Brain magnetic resonance imaging abnormalities in patients with heart failure

BACKGROUND: Although heart failure (HF) is a common cardiovascular disorder, to date little research has been conducted into possible associations between HF and structural abnormalities of the brain. AIMS: To determine the frequency and pattern of magnetic resonance imaging (MRI) abnormalities in outpatients with chronic HF, and to identify any demographic and clinical correlates. METHODS: Brain MRI scans were compared between a sample of 58 HF patients, 48 controls diagnosed with cardiovascular disease uncomplicated by HF (cardiac controls) and 42 healthy controls. Deep, periventricular and total white matter hyperintensities (WMH), lacunar and cortical infarcts, global and medial temporal lobe atrophy (MTA) were investigated. RESULTS: Compared to cardiac and healthy controls, HF patients had significantly more WMH, lacunar infarcts and MTA, whereas cardiac controls only had more MTA, compared to healthy controls. Age and left ventricular ejection fraction (LVEF) were independently associated with total WMH. Age and systolic hypotension were associated with MTA in HF patients and cardiac controls. CONCLUSION: Our results suggest that cardiac dysfunction contributes independently to the development of cerebral MRI abnormalities in patients with HF. Age and low LVEF are the principal predictors of cerebral WMH in patients with HF and in cardiac controls.     

Asymptomatic cerebrovascular lesions detected by magnetic resonance imaging in patients with systemic lupus erythematosus lacking a history of neuropsychiatric events.

OBJECTIVE: To clarify the extent of asymptomatic cerebrovascular involvement in systemic lupus erythematosus (SLE). PATIENTS AND METHODS: Cerebral magnetic resonance imaging (MRI) findings and ultrasonography findings of 100 patients with SLE lacking present or past clinical neurologic deficits were compared with 66 age-matched volunteers to determine the combined intima-media thickness (IMT) of the common carotid artery, and tests for anti-cardiolipin antibodies (aCL). RESULTS: Thirty-eight patients, but only 2 controls, showed imaging abnormalities. Among 23 SLE patients with cerebrovascular lesions by MRI who underwent single-photon emission computed tomography (SPECT), 14 showed hypoperfusion of the lesion. The IMT value and prevalence of aCL did not differ between the 55 SLE patients tested and controls. SLE disease activity index (SLEDAI) as assessed by a quantitative clinical index was significantly greater in patients with brain lesions than in those without. CONCLUSION: The prevalence of asymptomatic brain lesions in SLE patients is highs and shows a relationship to disease activity.     

Magnetic resonance imaging and proton magnetic resonance spectroscopy in neuro-Behçet's disease

OBJECTIVE: Neuro-Behcet's disease (NBD) is one of the most serious complications of Behcet's disease (BD). Proton magnetic resonance spectroscopy (1H MRS) has been proved to be useful in detecting neuro-metabolic abnormalities in various diseases affecting the brain. In this study, we attempted to characterize the magnetic resonance imaging (MRI) findings in Korean patients with NBD and then examined the usefulness of 1HMRS in evaluating the MRI-negative brain area of NBD patients. METHODS: We performed brain MRI in 18 BD patients with neurologic symptoms and signs. Seven NBD patients without thalamic lesions and 8 healthy controls underwent brain 1H MRS, in which an 8 ml voxel was placed in the left thalamus and the N-acetylaspartate (NAA)/creatine (Cr) ratio was measured. RESULTS: Fourteen of 18 BD patients were diagnosed as having NBD and 12 NBD patients (86%) had brain lesions on MRI. Most lesions were of high signal intensity on T2-weighted images and located in the midbrain, pons, basal ganglia, and white matter. On 1H MRS, the thalamic area without gross abnormalities on MRI showed a significantly lower NAA/Cr ratio in NBD patients compared to healthy controls (1.07 +/- 0.08 versus 1.54 +/- 0.27, P < 0.01). In 2 NBD patients, the NAA/Cr ratios, monitored serially, were normalized along with clinical improvement 6 months after treatment with prednisolone and immune suppressive agents. CONCLUSION: MRI is a very sensitive diagnostic method for NBD, and 1H MRS may be useful for the early detection and follow-up of MRI-negative NBD.     

The case for utilizing more strict quantitative Doppler echocardiographic criterions for diagnosis of subclinical rheumatic carditis

AIM: Our aim was to perform a comparative, quantitative and qualitative, analysis of valvar echocardiographic findings in patients with acute rheumatic fever, with or without clinical manifestations of carditis, as compared to healthy controls. METHODS AND RESULTS: We analyzed cross-sectional Doppler echocardiographic images of 31 patients with acute rheumatic fever diagnosed according to the Jones criterions as modified in 1992. Of 31 patients, 22 presented with clinical carditis, while 9 had subclinical carditis. The patients, and a control group of 20 healthy individuals, underwent cardiac examination and echocardiographic assessment, assessing quantitative and qualitative findings of mitral and aortic valvar abnormalities. The leaflets of the mitral valve were statistically thicker in those with clinical and subclinical carditis when compared to controls (p less than 0.001). We observed a greater frequency of mitral variance, convergence of mitral flow, and aortic regurgitation for those with clinical and subclinical carditis when compared to controls (p less than 0.001, p less than 0.001 and p equal to 0.003, respectively). Patients with clinical and subclinical carditis had more quantitative and qualitative changes in the parameters than did the controls. CONCLUSION: Echocardiography is a sensitive method to detect valvar abnormalities in patients with acute rheumatic fever and carditis. Additionally, by using regular standardized criterions, abnormalities that lead to a diagnosis of subclinical carditis are found in those patients with acute rheumatic fever in the apparent absence of cardiac involvement.     

1H magnetic resonance spectroscopy in monocarboxylate transporter 8 gene deficiency

CONTEXT: In monocarboxylate transporter 8 (MCT8) gene deficiency, a syndrome combining thyroid and neurological abnormalities, the central nervous system has not yet been characterized by magnetic resonance (MR) spectroscopy. OBJECTIVE: We studied whether the degree of dysmyelinization in MCT8 gene deficiency according to MR imaging (MRI) is coupled with abnormalities in brain metabolism. DESIGN: MRI and MR spectroscopy of the brain were performed twice in two MCT8 gene deficiency patients, for the first time at age 8-10 months and for the second time at age 17-28 months. The results were compared with those obtained in controls of a similar age. RESULTS: Compared with controls, young children with MCT8 show choline and myoinositol level increases and N-acetyl aspartate decreases in supraventricular gray and white matter, phenomena associated with the degree of dysmyelinization according to MRI. CONCLUSION: MCT8 gene deficiency results in deviant myelinization and general atrophy, which is substantiated by the MR spectroscopy findings of increased choline and myoinositol levels and decreased N-acetyl aspartate. The observations suggest that different mutations in the MCT8 gene lead to differences in the severity of the clinical spectrum, dysmyelinization, and MR spectroscopy-detectable changes in brain metabolism.     

神经精神狼疮患者局部脑血流灌注显像的临床研究

目的 观察神经精神狼疮患者脑血流改变,探讨神经精神狼疮患者局部脑血流灌注(rCBF)显像的临床意义.方法 20例神经精神狼疮患者(NPSLE组)、20例无神经精神表现的狼疮患者(SLE组)和20名年龄相当的健康志愿者(健康组)行单光子发射计算机断层(SPECT)rCBF显像,并划取感兴趣区作半定量分析得半定量(HQ)值.比较各组SPECT rCBF显像结果,并对HQ结果进行分析.同时20例神经精神狼疮患者行CT/磁共振成像(MRI)显像并与rCBF显像进行对比.结果 NPSLE组患者rCBF显像均阳性100%,其中19例局部脑血流降低,1例局部脑血流增加;20例患者CT/MRI头部显像阳性4例(20%),同rCBF显像相比差异有统计学意义(P＜0.01).SLE组患者rCBF显像阳性1例(5%),表现为局部脑血流降低.20名健康志愿者rCBF显像未见异常.NPSLE组患者rCBF显像病灶主要分布在颞叶(36%)、额叶(18%).其颞叶、额叶HQ值与SLE对照组和健康对照组比较,差异有统计学意义(P＜0.01和P＜0.05). 结论 rCBF显像灵敏度高,对早期诊断和治疗神经精神狼疮有重要意义.神经精神狼疮患者rCBF显像多表现为局部脑血流降低,好发部位为大脑中动脉供血区,以颞叶、额叶多见.     

Inflammatory changes of hip synovial structures in polymyalgia rheumatica

OBJECTIVE: To investigate the hip inflammatory lesions and to evaluate the accuracy of clinical examination compared to magnetic resonance imaging (MRI) in patients with polymyalgia rheumatica (PMR) with pelvic girdle symptoms. Secondary end-point was to evaluate the sensitivity and specificity of ultrasonography (US) compared to MRI in the assessment of hip lesions. METHODS: Case-control study of 20 consecutive PMR patients and 40 controls with different rheumatic conditions. Both groups were clinically assessed for the presence of hip synovitis, trochanteric, iliopsoas and ischiogluteal bursitis. Hip MRI was performed in all case-patients and in 10 controls. Both groups were examined by US. An additional group of 10 healthy controls was examined by hip US. RESULTS: Both MRI and US detected trochanteric bursitis in 100% of PMR patients, bilateral in 18/20 (90%), and in 12/40 (30%) controls (p < 0.001). Hip synovitis was detected in 17/20 (85%) by MRI and in 9/20 (45%) by US (p < 0.02) in case-patients and in 18/40 (45%) controls. In PMR, MRI and US showed iliopsoas bursitis in 10/20 (50%) and 6/20 (30%) and ischiogluteal bursitis in 5/20 (25%) and 4/20 (20%) with no differences compared to controls. Clinical examination showed a good accuracy for hip synovitis, trochanteric and ischiogluteal bursitis, while it overestimated the presence of iliopsoas bursitis. US was less sensitive than MRI for the detection of hip synovitis and iliopsoas bursitis (53% and 60%). CONCLUSION: Trochanteric bursitis represents the most frequent hip lesion in PMR. A careful physical examination allows to detect all inflammatory lesions excluding iliopsoas bursitis. US is less sensitive than MRI in the assessment of hip synovitis and iliopsoas bursitis.     

Cardiac magnetic resonance imaging abnormalities in systemic lupus erythematosus: a preliminary report

The purpose of this prospective, pilot study was to determine whether differences in myocardial T2 relaxivity can be identified among active systemic lupus erythematosus (SLE) patients with clinically suspected SLE myocarditis, other active SLE patients, inactive SLE patients and age and gender matched controls. Eleven consecutive female patients (six with active SLE and five with inactive SLE), and five age, gender and race matched healthy controls underwent imaging with echocardiography and cardiac magnetic resonance imaging (MRI). Echocardiographic measurements included left ventricular end diastolic (LVEDV) and end systolic volumes (LVESV), and mass (LVM) (all indexed to body mass); ejection fraction and cardiac output. The cardiac MRI measurement was the T2 relaxation time (an index of soft tissue signal, with higher levels suggestive of increased tissue water content). Patients with active SLE had significantly higher LVEDV and LVM than inactive SLE patients and healthy controls, and significantly larger LVESV than healthy controls. Myocardial T2 relaxation times were significantly higher in patients with active SLE compared to those with inactive SLE and to healthy controls, and remained higher even after excluding the two active SLE patients who had clinical myocarditis. The four active SLE patients who underwent repeat cardiac imaging studies after clinical improvement showed normalization of these myocardial abnormalities. The conclusion was that active SLE patients demonstrate abnormalities in myocardial structure manifested by high myocardial T2 relaxation times that normalized after clinical improvement in disease activity. These findings suggest that T2 relaxation values are a sensitive indicator of myocardial disease in patients with SLE and that myocardial T2 relaxation abnormality frequently occur in patients with active SLE, even in the absence of myocardial involvement by clinical criteria.     

Ectopic posterior pituitary and stalk abnormality predicts severity and coexisting hormone deficiencies in patients with congenital growth hormone deficiency

Certain pituitary imaging abnormalities are a specific indicator of hypopituitarism. The objective of this study is to compare phenotypical features with radiological findings in patients with congenital growth hormone deficiency (GHD). Magnetic Resonance imaging (MRI) was performed in 103 patients [72 with Isolated GHD (IGHD) and 31 with Combined Pituitary Hormone Deficiency (CPHD)]. Images were assessed for the following abnormalities: (1) small/absent anterior pituitary, (2) thin or interrupted pituitary stalk (PSA), and (3) Ectopic posterior pituitary (EPP), and (4) others. Radiological findings were correlated with the clinical and biochemical parameters. MRI abnormalities were observed in 48.6% patients with IGHD, 93.5% with CPHD. Jaundice, hypoxia, hypoglycemia and breech deliveries were more common in EPP/PSA group. EPP/PSA was observed in 87.1% patients with severe GHD (peak GH?<?3???g/L) as compared to 12.9% with mild to moderate GHD (peak GH: 3?C10???g/L). Amongst CPHD, EPP/PSA was present in 80% of subjects with associated hypocortisolism?±?hypothyroidism as compared to 18.2% of subjects with hypogonadism. Over a mean follow up period of 4.5?years, 5.4% of subjects with IGHD and abnormal MRI progressed to CPHD while none of those with normal MRI progressed. This study emphasizes a significant clinico-radiological correlation in Asian Indian GHD patients. MRI abnormalities in the hypothalamic pituitary area, especially EPP/PSA are more common in patients with CPHD and severe GHD. Among CPHD, EPP/PSA predicts association with hypothyroidism or hypocortisolism. IGHD with MRI abnormality may evolve into CPHD.     

Magnetic resonance imaging findings in patients with Brugada syndrome

INTRODUCTION: Cardiac magnetic resonance imaging (CMR) is a powerful diagnostic tool for evaluating cardiac structure and function. Recently, right ventricular wall-motion abnormalities were described using electron beam tomography in patients with Brugada syndrome. In the present study, we prospectively evaluated CMR findings in patients with Brugada syndrome compared to matched controls. METHODS AND RESULTS: CMR was performed on 20 consecutive patients with proven Brugada syndrome. The imaging protocol included breath-hold dark blood prepared T1-weighted multislice turbo spin-echo and gradient-echo images. Ventricular volumes and dimensions were compared to age- and sex-matched normal volunteers. The right ventricular outflow tract area was significantly enlarged in patients with Brugada syndrome compared to controls (11 vs 9 cm2, P = 0.018). There was a trend to larger right ventricular end-diastolic and end-systolic volumes and lower right ventricular ejection fraction in patients with Brugada syndrome compared to controls. However, none of the differences reached significance (P = 0.3, P = 0.08, and P = 0.06, respectively). There was no statistically significant difference in the left ventricular parameters between patients and controls. High intramyocardial T1 signal similar to fat signal was observed in 4 (20%) of the 20 patients compared to none of the controls. CONCLUSION: The findings support the view that subtle structural changes, such as right ventricular outflow tract dilation may point to a localized arrhythmogenic substrate in patients with Brugada syndrome.     

Referral of epileptic patients in North East Coast of West Malaysia an area with poor MRI coverage: an analysis

Advances in neuroimaging techniques, particularly Magnetic Resonance Imaging (MRI), have proved invaluable in detecting structural brain lesions in patients with epilepsy in developed countries. In Malaysia, a few electroencephalography facilities available in rural district hospitals run by trained physician assistants have Internet connections to a government neurological center in Kuala Lumpur. These facilities are more commonly available than MRI machines, which require radiological expertise and helium replacement, which may problematic in Southeast Asian countries where radiologists are found in mainly big cities or towns. We conducted a cross-sectional study over a two year period begining January 2001 on rural patients, correlating EEG reports and MRI images with a clinical diagnosis of epilepsy to set guidelines for which rural patients need to be referred to a hospital with MRI facilities. The patients referred by different hospitals without neurological services were classified as having generalized, partial or unclassified seizures based on the International Classification of Epileptic Seizures proposed by the International League Against Epilepsy (ILAE). The clinical parameters studied were seizure type, seizure frequency, status epilepticus and duration of seizure. EEG reports were reviewed for localized and generalized abnormalities and epileptiform changes. Statistical analysis was performed using logistic regression and area under the curve. The association between clinical and radiological abnormalities was evaluated for sensitivity and specificity. Twenty-six males and 18 females were evaluated. The mean age was 20.7 +/- 13.3 years. Nineteen (43.2%) had generalized seizures, 22 (50.0%) had partial seizures and 3 (6.8%) presented with unclassified seizures. The EEG was abnormal in 30 patients (20 with generalized abnormalities and 10 localized abnormalities). The MRI was abnormal in 17 patients (38.6%); the abnormalities observed were cerebral atrophy (5), hippocampal sclerosis (4), infarct/gliosis (3), cortical dysgenesis (2) and tumors (2). One patient had an arachnoid cyst in the right occipital region. Of the 17 patients with an abnormal MRI, 14 had an abnormal EEG, this difference was not statistically significant. There was no significant associaton between epileptographic changes and MRI findings (p = 0.078). EEG findings were associated with MRI findings (p = 0.004). The association between an abnormal EEG and an abnormal MRI had a specificity of 82.4%, while epileptogenic changes had a specificity of 64.7% in relation to abnormal MRI findings. This meants that those patients in rural hospitals with abnormal EEGs should be referred to a neurology center for further workup and an MRI to detect causes with an epileptic focus.     

Echocardiographic findings and the increased risk of stroke in nonvalvular atrial fibrillation.

We studied whether cardiac abnormalities contribute to the increased risk of stroke in patients with nonvalvular atrial fibrillation (NVAF). M-mode and 2D echocardiography were performed in four age- and gender-matched groups: 20 stroke patients with NVAF, 20 patients with NVAF who had not suffered a previous stroke, 20 stroke patients with sinus rhythm, and 40 healthy controls. Their mean age was 77 years. The two groups with atrial fibrillation differed from healthy controls in that they had more 2D-echocardiographic findings of severe left-ventricular-wall-motion abnormalities (p < 0.05) and tended more often to have enlarged left ventricles, and hypertrophic and congestive cardiomyopathy. Left atrial diameter was 47 mm compared to 41 and 39 mm in the two groups with sinus rhythm (p < 0.001). Intracardiac thrombi were only found in the two atrial-fibrillation groups (with stroke: 15% without stroke: 5%). Aortic sclerosis was common in all groups (30-60%), as was mitral annulus calcification (10-20%). The only significant difference between the two atrial-fibrillation groups was a higher frequency of earlier ischemic heart disease in the stroke group. Both atrial-fibrillation groups had cardiac abnormalities predisposing for embolic as well as thrombotic stroke.     

Cerebral imaging by magnetic resonance imaging and single photon emission computed tomography in systemic lupus erythematosus with central nervous system involvement

OBJECTIVE: To assess the significance of magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) abnormalities in patients with systemic lupus erythematosus (SLE). METHODS: Forty-four patients with SLE were retrospectively analysed. Patients were classified into three groups [1 and 2: patients with central nervous system (CNS) manifestations before and after starting high-dose steroid therapy, respectively; 3: patients without CNS manifestations. MRI was performed in all 44 patients and SPECT in 31. RESULTS: Abnormal findings in MRI were found in 19 patients. MRI abnormalities were significantly more frequent in patients with CNS manifestations than in those without [71 vs 17%, odds ratio (OR) 11.9, confidence interval (CI) 2.8-49.9, P=0.0003]. After the initiation of steroid therapy, patients with CNS manifestations also had an increased frequency of abnormal MRI. No correlation was found between SPECT findings and CNS manifestations. However, patients with CNS manifestations after starting steroids showed a markedly increased frequency of abnormal MRI and SPECT compared with those without CNS manifestations (80 vs 7%; OR 56, CI 4.4-719, P=0.0003). The positive predictive value of abnormality in both techniques in developing CNS manifestations after starting steroids was 89%. CONCLUSION: MRI findings correlated with CNS manifestations in SLE. Where there is a high suspicion of CNS involvement, the combination of MRI and SPECT may be useful in predicting CNS manifestations after starting steroid therapy.     

Cerebral MRI abnormalities and their association with neuropsychiatric manifestations in SLE: a population-based study

OBJECTIVE: To evaluate the volumetric brain magnetic resonance imaging (MRI) findings in a population-based sample of systemic lupus erythematosus (SLE) patients and to detect a possible relationship between cerebral MRI abnormalities and specific neuropsychiatric (NP) manifestations. METHODS: The study population consisted of patients with SLE (n = 43) in Pirkanmaa Health Care District, Finland and of a sex- and age-stratified reference group from the general population (n = 43). In addition to a clinical neurological investigation, all subjects received a detailed neuropsychological assessment and an MRI study. Volumetric measures of cerebral atrophy as well as T1- and T2-weighted lesions were obtained. SLE activity was assessed by the European Consensus Lupus Activity Measure (ECLAM) index, and accumulated NP abnormalities were measured by the Systemic Lupus International Collaborating Clinics (SLICC) damage index. A cumulative lifetime dose of glucocorticoids was determined from the patientrecords. RESULTS: Compared with controls, SLE patients had increased volumes of both T1- and T2-weighted lesions (p = 0.019 and p<0.0001, respectively) and increased cerebral atrophy (p<0.001). All the measured MRI parameters were statistically significantly higher in NPSLE than in non-NPSLE patients. In SLE patients, cerebral atrophy was associated with cognitive dysfunction, epileptic seizures, and cerebrovascular disease; T1-weighted lesions were associated with epileptic seizures and T2-weighted lesions with cognitive dysfunction. All MRI parameters correlated significantly with the SLICC index but not with the ECLAM index. A positive correlation was found between a cumulative dose of glucocorticoids and cerebral atrophy in SLE patients. CONCLUSION: MRI abnormalities, including brain atrophy and T1- and T2-weighted lesions, are significantly more common in patients with SLE than in the general population and they are related to specific NP manifestations. Our findings also provide support for the organic aetiology of cognitive dysfunction in SLE.     

A pilot assessment of whether external coil MRI is useful to assess evacuatory disorders

This study assessed the value of common surface coil mag-netic resonance imaging (MRI) in patients with evacuatory disorders including fecal incontinence and constipation. These findings were then compared with those from other standard physiological examinations and/or surgical findings. From July 1996 to June 1997, 14 consecutive patients underwent surface coil MRI for evaluation of either fecal incontinence (n=5) or constipation (n=9). In patients with incontinence we compared the findings from endoanal ultrasound (EAUS), anal MRI, and surgery regarding morphopathological findings of the internal and external anal sphincter components. In constipated patients the findings of videoprography and dynamic pelvic MRI were compared regarding the presence of rectocele, rectoanal intussusception, and sigmoidocele as well as the measurements of anorectal angle and perineal descent. The five incontinent patients were all women, with a median age of 67 years (range 43–77). EAUS revealed an anterior sphincter defect in two patients, a posterior defect in one, and normal anal sphincter images in two. Surgical findings confirmed an anterior external anal sphincter scar in two patients, an internal anal sphincter defect in one, and an anatomically normal anal sphincter in two. In one patient, although anal MRI showed posterior external anal sphincter defect, EAUS and surgery revealed normal external anal sphincter appearance. The accuracy rate between EAUS and anal MRI was only 20%, that between surgery and anal MRI 40%, and that between surgery and EAUS 80%. Thus EAUS was more accurate than anal MRI in incontinent patients. The nine constipated patients were all women, with a mean age of 59 years (range 40–78). Videoproctography revealed an anterior rectocele in six patients, rectoanal intussusception in three, and sigmoidocele in five; no abnormalities were identified in two patients. On dynamic pelvic MRI anterior rectocele was seen in three patients and sigmoidocele in two, and five studies were interpreted as normal. One of the patients underwent sigmoidectomy for sigmoidocele, and five patients were treated by biofeedback. Thus the accuracy rate of dynamic pelvic MRI against videoproctography was 60% for anterior rectocele, 40% for sigmoidocele, and zero for rectoanal intussusception. In conclusion, neither MRI for the evaluation of patients with fecal incontinence nor for the evaluation of patients with constipation added any significant information that would warrant its continued use in these patient groups. Perhaps the more widespread availability of an endoanal coil will alter this conclusion; however, at the present time we cannot routinely endorse the expense, time, or inconvenience of these MRI investigations in patients with these diagnoses. Larger prospective comparative studies are required prior to endorsing the technique. Accepted: 21 February 2000     

Clinical and electrophysiological differences between patients with arrhythmogenic right ventricular dysplasia and right ventricular outflow tract tachycardia.

AIMS: Radiofrequency catheter ablation is considered first line treatment for symptomatic patients with right ventricular outflow tract tachycardia (RVOT). The role of ablation in arrhythmogenic right ventricular dysplasia (ARVD) is more limited. As such, differentiating between the two conditions is essential. METHODS AND RESULTS: This study compared non-invasive findings, magnetic resonance images (MRI), invasive electrophysiological characteristics, results of ablation and long-term outcome in 50 consecutive patients with RVOT (33) or ARVD (17). Structural abnormalities were uniform in the ARVD group; in addition 18 (54%) of the RVOT tachycardia group had MRI abnormalities. At electrophysiological study the tachycardia in the ARVD group displayed features of re-entry in over 80%, but behaved with a triggered automatic basis in 97% with RVOT. Ablation was complete or partial success in 12 (71%) patients with ARVD and ventricular tachycardia (VT) recurred in eight (48%). In the RVOT patients, ablation was a complete success in 97% with recurrent VT in 6%. Long-term success in the RVOT patients was 95% in both patients with and without MRI abnormalities. CONCLUSIONS: Electrophysiological characterization can differentiate ARVD from RVOT. The finding of abnormalities on MRI does not have any bearing on arrhythmia mechanism, acute or long-term success of RFA.     

Brain magnetic resonance imaging findings in young patients with hepatosplenic schistosomiasis mansoni without overt symptoms

The purpose of this study was to describe the brain magnetic resonance imaging (MRI) findings in young patients with hepatosplenic schistosomiasis mansoni without overt neurologic manifestations. This study included 34 young persons (age range = 9-25 years) with hepatosplenic schistosomiasis mansoni who had been previously treated. Patients were scanned on a 1.5-T system that included multiplanar pre-contrast and post-contrast sequences, and reports were completed by two radiologists after a consensus review. Twenty (58.8%) patients had MRI signal changes that were believed to be related to schistosomiasis mansoni. Twelve of the 20 patients had small focal hyperintensities on T2WI in the cerebral white matter, and eight patients had symmetric hyperintense basal ganglia on T1WI. There was a high frequency of brain MRI signal abnormalities in this series. Although not specific, these findings may be related to schistosomiasis.     

Magnetic resonance imaging findings in patients meeting task force criteria for arrhythmogenic right ventricular dysplasia

INTRODUCTION: Magnet resonance imaging (MRI) findings in patients meeting Task Force criteria for the diagnosis of arrhythmogenic right ventricular dysplasia (ARVD) have not been systematically described. We report qualitative and quantitative MRI findings in ARVD using state-of-the-art MRI. METHODS AND RESULTS: MRI was performed on 12 patients with ARVD who were prospectively diagnosed using the Task Force criteria. The imaging protocol included breath-hold double inversion recovery spin-echo and gradient-echo images. Ventricular volumes and dimensions were compared to 10 age- and sex-matched normal volunteers. High intramyocardial T1 signal similar to fat signal was observed in 9 (75%) of the 12 patients and in none of the controls. Right ventricular (RV) hypertrophy was seen in 5 (42%) patients, trabecular disarray in 7 (59%), and wall thinning in 3 (25%). Both the RV end-diastolic diameter and the outflow tract area were significantly higher in ARVD patients compared to controls (51.2 vs 43.2 mm, P < 0.01; and 14.5 vs 9.3 cm2, P < 0.01, respectively). ARVD patients had a higher RV end-diastolic volume index and lower RV ejection fraction compared with controls (127.4 vs 87.5, P < 0.01; and 41.6% vs 57%, P < 0.01, respectively). CONCLUSION: High intramyocardial T1 signal indicative of fat is seen in a high percentage (75%) of patients who meet the Task Force criteria for ARVD. Trabecular disarray is seen more frequently than wall thinning and aneurysms. RV dimensions and volumes differ significantly in ARVD compared to controls, indicating a role for quantitative evaluation in the diagnosis of ARVD.     

Ill-defined neurological syndromes with autoimmune background: a diagnostic challenge

OBJECTIVE: To define the diagnostic features of a cohort of patients presenting with autoimmune manifestations and atypical neurological features not fulfilling criteria for a well defined neurological or connective tissue disorder. METHODS: Twenty-nine such patients were referred to our institution for evaluation. Nine were excluded from this study since they were diagnosed with antiphospholipid syndrome. The remaining 20 patients underwent complete clinical and laboratory evaluation, spinal fluid analysis, minor salivary gland biopsy (if sicca features were present), and were tested for evoked potentials. Magnetic resonance imaging (MRI) scans of the brain were performed in all patients and of the spine in 7. RESULTS: Brain and/or spinal cord MRI abnormalities were found in all 20 patients. Based on morphologic criteria and distribution, these lesions were classified into 3 subsets: (1) multiple sclerosis (MS)-like (4 patients); (2) vasculitic (8 patients); and (3) nonspecific (8 patients). The most frequent underlying abnormality in patients with subgroups 1 and 2 were the presence of homozygous methylenetetrahydrofolate reductase (MTHFR) mutations (5 of 12, 41.6%). The most common findings among subgroup 3 were the presence of antithyroid antibodies (6 of 8 patients, 75%). CONCLUSION: Homozygous MTHFR mutations are frequently encountered in patients presenting with neurological features and MS-like or vasculitic type MRI abnormalities in a setting of autoimmune disease. Nonspecific MRI changes are frequently associated with antibodies against thyroid antigens.