Cerebral Magnetic Resonance Imaging Findings Research Articles

Magnetic Resonance Imaging in Uremic Encephalopathy: Identifying Key Imaging Patterns and Clinical Correlations.

Background/Objectives: Magnetic Resonance Imaging (MRI) is essential in diagnosing neurological conditions, offering detailed insights into brain pathology. Uremic encephalopathy (UE) is a severe neurological disorder resulting from renal failure, characterized by cognitive impairments and brain abnormalities due to the accumulation of uremic toxins (UTs). Despite extensive research on UTs, there is a significant gap in the detailed characterization of MRI findings in UE patients. This study aims to bridge this gap by conducting a comprehensive literature review of cerebral MRI findings in UE. We hypothesize that specific MRI patterns correlate with the severity and clinical manifestations of UE, thereby enhancing diagnostic accuracy and improving patient outcomes. Methods: A literature review was performed using PubMed, Cochrane Library, and Google Scholar. The search terms included "uremic encephalopathy MRI", "uremia and kidney failure MRI", and "toxic and metabolic or acquired encephalopathies MRI". The inclusion criteria were original articles on UE and MRI findings published in English. Results: Common MRI sequences include T1-weighted, T2-weighted, FLAIR, and DWI. Frequent MRI findings in UE are cytotoxic and vasogenic brain edema in regions such as the basal ganglia and periventricular white matter. Patterns like the "lentiform fork sign" and basal ganglia involvement are key indicators of UE. Conclusions: MRI plays a crucial role in diagnosing UE by identifying characteristic brain edema and specific patterns. A comprehensive diagnostic approach, incorporating clinical, laboratory, and imaging data, is essential for accurate diagnosis and management. The study calls for larger well-designed cohorts with long-term follow-up to improve the understanding and treatment of UE.

The Clinical Spectrum and Outcome of Uveomeningitis: A Comprehensive Analysis of 110 Cases

ABSTRACT Purpose: Uveitis can be associated with meningitis (uveomeningitis) and the inflammation shared with the central nervous system. We aimed to describe the characteristics and outcome of uveomeningitis. Methods: We retrospectively analyzed 110 consecutive adult patients with uveomeningitis. Results: The main causes of uveomeningitis were Vogt–Koyanagi–Harada (31%), syphilis (16%), sarcoidosis (12%), Behçet’s disease (7%), and multiple sclerosis (5%). Sixteen percent of uveomeningitis remained of undetermined origin. Compared to etiology-matched uveitis without meningitis, patients with uveomeningitis were younger, had more frequent neurological manifestations, and had more frequent abnormal cerebral magnetic resonance imaging findings. In contrast, no ocular feature upon examination was significantly associated with the presence of meningitis. Patients with uveomeningitis were more frequently treated with immunosuppressants but uveitis relapse and systemic complications did not differ between groups. Conclusion: Uveomeningitis is associated with a limited spectrum of diseases. Meningitis does not seem to impact ocular and extraocular outcomes. Therefore, lumbar puncture should be performed on an individual basis during the diagnostic workup of uveitis.

Pontocerebellar hypoplasia type 11: Does the genetic defect determine timing of cerebellar pathology?

Pontocerebellar hypoplasia (PCH) comprises a clinically and genetically heterogeneous group of disorders characterized by hypoplasia and degeneration of the cerebellum and ventral pons. To date at least 18 different clinical subtypes of PCH associated with pathogenic variants in 19 different genes have been described. Only recently, bi-allelic variants in TBC1D23 have been reported as the underlying molecular defect in seven index cases with a suspected non-degenerative form of PCH, PCH type 11 (PCH11). We used exome sequencing to investigate an individual with global developmental delay, ataxia, seizures, and progressive PCH. Brain volume was evaluated over a disease course of 14 years using volumetric magnetic resonance imaging (MRI). Volume alterations were compared to age-matched controls as well as data from children with PCH2. We identified a homozygous frameshift variant in exon 9 of 18 of TBC1D23 predicting a loss of protein function. Brain morphometry revealed a pattern of pontine, brain stem, and supratentorial volume loss similar to PCH2 patients although less pronounced. Intriguingly, cerebral MRI findings at the age of 1 and 15 years clearly showed progressive atrophy of the cerebellum, especially the hemispheres. In four of the cases reported in the literature cerebellar hemispheres could be evaluated on the MRIs displayed, they also showed atrophic foliae. While pontine hypoplasia and pronounced microcephaly are in line with previous reports on PCH11, our observations of clearly postnatal atrophy of the cerebellum argues for a different pathomechanism than in the other forms of PCH and supports the hypothesis that TBC1D23 deficiency predominantly interferes with postnatal rather than with prenatal cerebellar development.

Brain abnormalities in infantile esotropia as predictor for consecutive exotropia

ABSTRACT Cerebral palsy, neurological abnormalities, prematurity or periventricular lesions may affect motor and sensory fusion mechanisms that favorably control eye alignment. White matter damage of immaturity (WMDI) is a form of white matter brain injury characterized by the necrosis of white matter near the lateral ventricles. In these cases, it is difficult to establish fusion after strabismus surgery and consecutive deviations may be seen more frequently especially in association with WMDI. The aim of this study is to evaluate and compare the cerebral magnetic resonance imaging (MRI) findings in operated infantile esotropia cases with and without consecutive exotropia and to relate them to the occurance of consecutive exotropia. Seventeen patients that had consecutive exotropia after bilateral medial rectus recession surgery for infantile esotropia were included in this study (group 1) and patients that were operated with the same diagnosis with a successful surgical outcome (≤10 PD of deviation) were recruited as group 2. Age, sex, consanguinity, associated systemic and neurological diseases, prematurity, visual acuity, angle of deviations at first visit, at last and follow-up visit and after surgery, cycloplegic retinoscopy, fundus and cerebral MRI findings were recorded. Demographic and clinical findings of patients in two groups and MRI findings were evaluated and compared. The mean age at the time of first examination was 8.21 ± 6.62 and 7.45 ± 4.94 months in infantile esotropia patients with (group 1) and without consecutive exotropia (group 2), respectively. The mean cycloplegic refractive errors (+1.92 ± 1.57 D vs. +2.30 ± 1.10 D), the mean preoperative angle of deviation (46.33 ± 18.8 PD vs. 34.8 ± 12.5 PD), sex, percentage of consanguinity, percentage of prematurity, presence of latent nystagmus, dissociated vertical deviation and amblyopia and fundus findings were similar in both groups. Patients with consecutive exotropia had a mean deviation angle of 37.5 ± 9.48 PD postoperatively. Cerebral MRI findings were consistent with WMDI (three patients), myelinization delay (one patient), septooptic dysplasia (one patient) and periventricular cysts (one patient) in group 1. Cerebellar hemispheres and vermis hypoplasia (one patient), myelinization delay (one patient), cerebellar atrophy (one patient) were the MRI findings of patients in group 2. White matter damage of immaturity was only present in the consecutive exotropia group. This finding may suggest that WMDI can be a risk factor for consecutive deviation in infantile esotropia patients.

Magnetic Resonance Imaging Findings Related to Stroke Risk in Japanese Patients With Fabry Disease.

Background and Purpose- Stroke is the most frequent severe clinical event in patients with Fabry disease. We aimed to evaluate the cerebral magnetic resonance imaging findings of patients with Fabry disease and assess their association with future stroke risk after enzyme replacement therapy (ERT) induction. Methods- We retrospectively reviewed the magnetic resonance imaging findings of 25 patients with Fabry disease. Of these, 12 adult patients without prior stroke or ERT were enrolled to evaluate the association between baseline magnetic resonance imaging findings and stroke occurrence after ERT initiation. We assessed white matter hyperintensities, periventricular hyperintensities, and basilar artery diameter as neuroimaging markers. Results- The mean age of participants was 38.8±16.8 years. Fourteen patients (56.0%) were women. White matter hyperintensities and periventricular hyperintensities were observed in 15 and 13 cases, respectively. The mean basilar artery diameter was 3.2±0.55 mm. Two patients demonstrated old infarct lesions. Three of 12 patients in whom ERT was initiated had symptomatic stroke after baseline magnetic resonance imaging. Of these, 2 developed stroke within 6-month post-ERT initiation. The baseline basilar artery diameter was larger in patients who developed stroke than in those who did not (4.0±0.40 versus 2.9±0.49 mm, P=0.02). Conclusions- Basilar artery diameter may be associated with stroke risk after ERT initiation among Japanese patients with Fabry disease.

Magnetic resonance imaging and magnetic resonance venography features in heat stroke: a case report

BackgroundHeat stroke (HS) is a critical illness that can cause multiple organ dysfunction, including damage to the central nervous system (CNS), which can be life-threatening in severe cases. Brain lesions in patients with HS who present with CNS damage have been rarely reported before, and they usually vary in different cases, hence, patients with such lesions may present a clinical challenge in terms of diagnosis and management. Cerebral venous thrombosis (CVT) is a rare cause of stroke that mostly affects young individuals and children. The pathogenesis of brain damage caused by HS is complex, and CVT may be involved in the pathogenesis of HS with CNS damage. In this manuscript, we have reported a case of a patient with HS having CVT with symmetrical lesions in the bilateral putamen, posterior limb of the internal capsule, external capsule, insular lobe, and subcortical white matter in the brain.Case presentationWe encountered a 48-year-old man who presented with HS in the summer season. During admission, he had a high body temperature and was in coma and shock. Then, he developed rhabdomyolysis syndrome, acute kidney and liver damage, electrolyte imbalance, and acid–base balance disorders, and his D-dimer level was elevated. After several days of anti-shock treatment, the patient’s level of consciousness improved. However, he experienced a decline in vision. Cerebral magnetic resonance imaging (MRI) showed symmetrical lesions in the bilateral posterior limb of the internal capsule, putamen, external capsule, insula, and subcortical white matter, and cerebral magnetic resonance venography (MRV) showed the development of CVT. Therefore, anti-coagulation treatment was provided. After timely clinical intervention, the symptoms of the patient gradually improved.ConclusionsThis case showed that HS can cause CVT. Therefore, cerebral MRI findings in HS must be assessed; in addition, early MRV can help in the diagnosis of the disease, which can effectively improve prognosis.

Clinical Diagnosis, Biochemical Findings, Genetics and Incidence of Zellweger Syndrome

Objectives: To analyze the clinical and laboratory data of neonates diagnosed with Zellweger syndrome and to estimate the incidence of the syndrome. Methods: The databases of four institutions that admitted newborns diagnosed with Zellweger syndrome to intensive care units between January 2013 and December 2016 were examined. Results: A total of 105,887 live babies were born in the four centers during the study period. Seven were diagnosed with Zellweger syndrome; the incidence was thus 1/15,126. Birth weights were 2,200 - 3,300 g. Six cases were born to consanguineous parents. Dysmorphic findings, respiratory failure, and hypotonia were evident in all patients. Hepatomegaly was apparent in four cases, congenital cardiac defects in four, characteristic cerebral magnetic resonance imaging findings in four, renal cysts in five, hepatic cysts in three, and splenomegaly in one. PEX1 mutations were identified in three patients, and one mutation was novel. Conclusions: The incidences of Zellweger syndrome and cardiac disease were higher than reported previously, being (to the best of our knowledge) among the highest reported worldwide. This is the first time that such incidences have been calculated in Turkey. The syndrome is more common in regions where consanguineous marriage rates are higher.

Placental Pathology in Full-Term Infants with Hypoxic-Ischemic Neonatal Encephalopathy and Association with Magnetic Resonance Imaging Pattern of Brain Injury

To investigate the relationship between placental pathology and pattern of brain injury in full-term infants with neonatal encephalopathy after a presumed hypoxic-ischemic insult. The study group comprised full-term infants with neonatal encephalopathy subsequent to presumed hypoxia-ischemia with available placenta for analysis who underwent cerebral magnetic resonance imaging (MRI) within the first 15 days after birth. Macroscopic and microscopic characteristics of the placenta were assessed. The infants were classified according to the predominant pattern of brain injury detected on MRI: no injury, predominant white matter/watershed injury, predominant basal ganglia and thalami (BGT) injury, or white matter/watershed injury with BGT involvement. Maternal and perinatal clinical factors were recorded. Placental tissue was available for analysis in 95 of 171 infants evaluated (56%). Among these 95 infants, 34 had no cerebral abnormalities on MRI, 27 had white matter/watershed injury, 18 had BGT injury, and 16 had white matter/watershed injury with BGT involvement. Chorioamnionitis was a common placental finding in both the infants without injury (59%) and those with white matter/BGT injury (56%). On multinomial logistic regression analysis, white matter/watershed injury with and without BGT involvement was associated with decreased placental maturation. Hypoglycemia was associated with an increased risk of the white matter/BGT injury pattern (OR,5.4; 95% CI, 1.4-21.4). The BGT injury pattern was associated with chronic villitis (OR, 12.7; 95% CI, 2.4-68.7). A placental weight <10th percentile appeared to be protective against brain injury, especially for the BGT pattern (OR, 0.1; 95% CI, 0.01-0.7). Placental weight <10th percentile was mainly associated with normal cerebral MRI findings. Decreased placental maturation and hypoglycemia <2.0 mmol/L were associated with increased risk of white matter/watershed injury with or without BGT involvement. Chronic villitis was associated with BGT injury irrespective of white matter injury.

Cerebral Magnetic Resonance Imaging Findings in Children Born Extremely Preterm, Very Preterm, and at Term

The aim of this study was to compare findings on cerebral MRI scans of infants born extremely preterm (i.e., gestation < 28 weeks, very preterm; gestation 28-31 weeks) and at term. MRI scans obtained in a cohort of 29 extremely preterm children at 11 years, 51 very preterm young adults at 19 years, and respective term-born controls were scored according to presence and degree of MRI pathology. MRI pathology was found in 76% of the extremely preterm children vs 31% of their controls (odds ratio 4.3; 95% confidence interval, 1.5-137.5) and in 55% of the very preterm group vs 19% of their controls (odds ratio 5.2; 95% confidence interval, 2.5-10.9). The distribution of moderate and severe pathology did not differ among the groups. The extremely preterm, very preterm, and term subjects shared the same morphological pathology, revealing no specific preterm MRI pattern, but both premature cohorts had higher frequencies. Differences were mainly limited to mild pathology. Whether MRI lesions were more common in the extremely preterm than in the very preterm group is uncertain as the difference in frequency was similar in the two control groups, suggesting a lack of objective criteria for differentiating mild pathology from normality or that MRI scans normally differ at 11 and 19 years of age.

Cerebral Magnetic Resonance Imaging Findings in Adults with Haemolytic Uraemic Syndrome Following an Infection with Escherichia coli, Subtype O104:H4

Infections with Enterohaemorrhagic Escherichia coli typically occur in children causing haemolytic uraemic syndrome (HUS) and neurological symptoms in 20-50 %. Little information is available on the morphology of brain manifestations in adults. The purpose of this study was to identify a characteristic magnetic resonance imaging (MRI) pattern during the outbreak of a novel mutation of Escherichia coli O104:H4. Patients were recruited from two hospitals between May and July 2011. The MRI protocol included standard anatomical, diffusion-weighted, and susceptibility-sensitive sequences. A total of 104 MRIs of 57 (32 female, 25 male) patients (mean 45.5 ± 18.4 years) showed abnormal signal intensity on 51 MRIs (49 %). Bilateral thalamus (39 %), bilateral pons (35 %), centrum semiovale and splenium of corpus callosum (33 %) were most often involved. Acute lesions were reversible in 81 % of cases. There was no statistically significant association between symptom onset and the MRI findings (P = 0.2). Neuroimaging findings in this adult patient cohort were non-specific and similar to previous findings in children. A characteristic neuroimaging pattern of an infection with Escherichia coli O104:H4 was not identified. However, bilateral symmetric T2 hyperintense lesions of the thalami and dorsal pons characterized by restricted diffusion suggest a metabolic toxic effect of the disease on the brain.

Early-onset or rapidly progressive scoliosis in children: Check the eyes!

Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare autosomal recessive disorder characterized by the absence of conjugate horizontal eye movements, and progressive scoliosis developing in childhood and adolescence, caused by mutations in the ROBO3 gene which has an important role in axonal guidance and neuronal migration. We describe two female children aged 12 years and 18 months, with progressive scoliosis, in whom the neurological examination showed absent conjugate horizontal eye movements, but preserved vertical gaze and convergence. Cerebral Magnetic resonance imaging findings included pontine hypoplasia, absent facial colliculi, butterfly configuration of the medulla and a deep midline pontine cleft, while Diffusion tensor imaging (DTI) maps showed the absence of decussating ponto-cerebellar fibers and superior cerebellar peduncles. Somatosensory and motor evoked potential studies demonstrated ipsilateral sensory and motor responses. The diagnosis was confirmed by the identification of bi-allelic mutations in the ROBO3 gene.

Infective Endocarditis with Symptomatic Cerebral Complications: Contribution of Cerebral Magnetic Resonance Imaging

Background: Cerebral complications are well-identified causes of morbidity and mortality in patients with infective endocarditis (IE). Few studies have analysed the impact of brain magnetic resonance imaging (MRI) in IE patients with neurological manifestations. Objectives: The aims of this study were to assess the MRI contribution to the management of patients with IE neurological manifestations and to compare cerebral CT and MRI findings. Material and Methods: Patients with definite or probable IE and neurological manifestations were prospectively enrolled from 2005 to 2008, in a university hospital (Bichat Claude Bernard Hospital, Paris). Clinical and radiological characteristics and echocardiographic findings were systematically recorded. Brain MRI with angiography was performed and compared to available CT scans. The contribution of MRI results to cerebral involvement staging and to therapeutic plans was evaluated. Results: Thirty patients, 37-89 years old, were included. Nineteen suffered from pre-existing heart disease. Blood cultures were positive in 29 cases and the main micro-organisms were streptococci (n = 14) and staphylococci (n = 13). The IE was mainly located on mitral (n = 15) and aortic valves (n = 13). Neurological events were strokes (n = 12), meningitis (n = 5), seizures (n = 1), impaired consciousness (n = 11) and severe headache (n = 1). MRI findings included ischaemic lesions (n = 25), haemorrhagic lesions (n = 2), subarachnoid haemorrhage (n = 5), brain abscess (n = 6), mycotic aneurysm (n = 7), vascular occlusion (n = 3) and cerebral microbleeds (n = 17). In 19/30 cases, neurological manifestations were observed before the diagnosis of IE. MRI was more sensitive than CT scan in detecting both clinically symptomatic cerebral lesions (100 and 81%, respectively) and additional asymptomatic lesions (50 and 23%, respectively). Therapeutic plans were modified according to MRI results in 27% of patients: antibiotherapy regimen modifications in 7% (switch for molecules with high cerebral diffusion) and surgical plan modifications in 20% (indication of valvular replacement due to the embolic nature of the vegetations revealed by MRI or postponement of surgery due to haemorrhagic lesions). None of the 16/30 (51%) operated-on patients experienced postoperative neurological worsening. In-hospital death occurred in 4 patients. Conclusion: In patients with IE neurological manifestations, MRI revealed a broader involvement of the brain (type and number of lesions) than indicated by clinical signs and/or CT scan. With a better disease staging of neurological manifestations, MRI brain imaging may help in patient management and the decision-making process especially for cardiac surgery indication and timing of valve replacement.

Quantitative MRI shows cerebral microstructural damage in hemolytic–uremic syndrome patients with severe neurological symptoms but no changes in conventional MRI

Severe neurological symptoms in Shiga toxin-producing Escherichia coli infection associated hemolytic-uremic syndrome (STEC-HUS) are often accompanied by none or only mild alterations of cerebral magnetic resonance imaging (MRI). This study aims to analyze if quantitative MRI is able to reveal cerebral pathological alterations invisible for conventional MRI. In nine patients with STEC-HUS associated severe neurological symptoms but inconspicuous cerebral MRI findings maps of the parameters T2 relaxation time, relative proton density (PD), apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were generated. Quantitative values of these parameters were measured at the basal ganglia, thalamus, and white matter of the frontal and parietal lobe and compared to those of nine age- and sex-matched controls. Significant T2 prolongation (p < 0.01) was found in the basal ganglia of all patients compared to controls. PD and ADC were not significantly altered. A significant reduction of FA in patients was seen at caput nuclei caudati (p < 0.01). Prolonged T2 relaxation time indicates cerebral microstructural damages in these patients despite their inconspicuous MRI findings. T2 relaxometry could be used as a complementary tool for the assessment of metabolic-toxic brain syndromes.

Respective effects of early cerebral and abdominal magnetic resonance imaging on clinical decisions in infective endocarditis

Extracardiac complications of endocarditis influence diagnosis, therapeutic plans, and prognosis. The aim of this study was to assess how early combined cerebral and abdominal magnetic resonance imaging (MRI) affects the diagnosis and management of adults with endocarditis. In a single-centre prospective study, 58 patients with endocarditis underwent systematic cerebral and abdominal MRI within 7 days following admission. Diagnostic classification (Duke's modified criteria) and therapeutic plans were established by two experts just before and after MRI and then compared. Endocarditis was initially classified as definite in 29 patients, possible in 27, and excluded in 2. MRI detected cerebral lesions in 47 patients (81%) (ischaemic lesions in 25, microbleeds in 32, and silent aneurysms in 6), and abdominal lesions in 20 patients (34%). Based solely on MRI results without taking microbleeds into account, experts upgraded endocarditis diagnostic classification in 8 out of 29 (28%) non-definite endocarditis cases either to definite in 6 or to possible in 2. This upgrading was exclusively due to cerebral MRI in four patients and to cerebral and/or abdominal MRI in four patients. Experts modified endocarditis therapeutic plans in 11 (19%) out of the 58 patients, based solely on cerebral MRI, including modification of surgical plans in six (10%) patients. Overall, early MRI led experts to modify classification and/or therapeutic plans in 16 (28%) patients. MRI identified cerebral and/or abdominal asymptomatic lesions in many patients with endocarditis, but more frequently cerebral. Both cerebral and abdominal MRI findings affected diagnosis, but only cerebral MRI affected clinical management plans. CLINICALTRIALS.GOV IDENTIFICATION NUMBER: NCT 00144885. IRB AUTHORIZATION NUMBER: 0511114 (Comité Protection des Personnes Paris-Ile de France 1).

Clinical and Radiologic Manifestations of H1N1 Virus Infection Associated With Neurological Complications

Encephalitis complicating novel influenza A (H1N1) viral infection is rare and has only been reported in children. We present cerebral magnetic resonance imaging findings from a confirmed adult case with H1N1 infection who presented with acute encephalitis and subsequent respiratory failure. Cerebral magnetic resonance imaging showed hyperintense abnormalities in the bilateral globus pallidus in T1-weighted images, and multiple hyperintense abnormalities in the right insular cortex, right parahippocampus, and the pontine tegmentum in fluid-attenuated inversion recovery images.

Advances in Vascular Cognitive Impairment

Advances in Vascular Cognitive Impairment

Cerebral MRI findings in a cohort of ex‐preterm and control adolescents

Newborn infants were entered between 1988 and 1993 into a prospective, long-term, follow-up study. We aimed to investigate how the outcome of preterm-born individuals on cerebral magnetic resonance imaging (MRI) compared to that reported on similar cohorts internationally. The 74 ex-preterm (12.38-17.7 years, 51% girls) and 69 control participants (12.18-16.47 years, 53% girls) underwent a MRI examination on a 1.5T scanner. Two experienced neuroradiologists examined the T1- and T2-weighted images first independently and then in consensus without knowledge of group adherence. Only 21 (4 controls) of the 143 sets of scans showed any abnormalities. All but one of these were of mild extent. Among the ex-preterm adolescents two showed only incidental findings while the other 15 had either gliosis or white matter loss. Eleven subjects had white matter loss, seven of which had no other abnormalities. Four subjects had gliosis, three of which had no other abnormalities. The extent, severity or frequency of injury was not related to being born small for gestational age. Although the rate of structural abnormalities was higher in the group of adolescents born preterm, this rate was well below that reported from other centres around the world. We attribute this to the minimally invasive neonatal care and to different social structures in Sweden compared to that of other reports on similar cohorts.

Worsened MRI Findings During the Early Period of Treatment with Penicillin in a Patient with General Paresis

A 52-year-old man was diagnosed with general paresis, whose HIV antibodies were negative. After initiation of treatment with penicillin on the first day, no obvious clinical Jarisch-Herxheimer reaction was found. However, 6 days after treatment, the patient was found more irritable and was unable to fall asleep at night. On the seventh day, worsened magnetic resonance imaging (MRI) abnormalities in the bilateral medial and anterior temporal lobes were unexpectedly discovered. These worsened MRI abnormalities improved quickly after the addition of dexamethasone treatment. We consider that these transient and slight mental symptoms may be associated with the transiently worsening phenomenon in cerebral MRI findings during the early period of treatment with penicillin. This indicates that some nonspecific inflammatory process has happened in the early stage of treatment, which necessitates the use of corticosteroids after the occurrence of systemic or mental symptoms.

Centropontine myelinolysis after correction of hyponatremia: role of associated hypokalemia

Patients with severe hyponatremia have a high risk for centropontine myelinolysis (CPM) during treatment, but the incidence rate and risk factors have not been well-assessed. This study was conducted in a medical intensive care unit (ICU) of a university teaching hospital. All patients with a serum sodium concentration < 120 mmol/l and a serum osmolality level < 250 mosmol/kg upon ICU admission were enrolled in this prospective study and were included if they underwent a baseline brain computerized tomography scan (CT scan) and a follow-up brain magnetic resonance imaging 1 month after admission. The diagnosis of CPM was based on cerebral magnetic resonance imaging findings, i.e. T1-weighted images with T2-weighted images showing hyperintense signal in the corresponding areas which were not apparent on the initial cerebral CT scan. RESULTS. Of the 22 patients included, 12 were considered as having acute hyponatremia and 8 were chronic alcoholics. In 12 patients, the increase in serum sodium level was < 12 mmol/I in any 24-hour period. CPM was diagnosed in 7/22 patients (31.8%) and was asymptomatic in 4 of them. CPM was present in 4 patients with acute hyponatremia and in 4 chronic alcoholics. It was associated with a lower baseline potassium level (p = 0.05) and NaCl administration during the first 24 hours (p = 0.005). However, non-acute hyponatremia, chronic alcoholism and rapid correction of serum sodium did not appear as risk factors. The incidence rate of CPM following severe hyponatremia is high and can develop even when there is a slow correction of serum sodium level. Hypokalemia is a predisposing factor.

Preoperative cerebral ischemic lesions predict physical health status after on-pump coronary artery bypass surgery

Risk assessment is integral to patient selection and counseling before coronary artery revascularization. We studied the predictive ability of cerebral magnetic resonance imaging of preoperative and postoperative cerebral ischemic injury on self-reported physical and mental health at 3 months after coronary artery bypass surgery with or without use of cardiopulmonary bypass. In a prospective clinical trial comparing on-pump and off-pump surgery, 120 patients responded to a questionnaire for self-report of angina (Canadian Cardiovascular Society scale) and physical and mental health status (Short Form 36) at baseline before preoperative cerebral magnetic resonance imaging. Preoperative sets of both magnetic resonance imaging and self-assessments were available for 103 (85.8%) patients. These patients were grouped according to classification of preoperative cerebral magnetic resonance imaging findings. Analysis of covariance determined the association of (1) preoperative magnetic resonance imaging status, (2) new postoperative cerebral lesions, and (3) actual use of cardiopulmonary bypass to physical and mental health. At 3 months after surgical intervention, 98 of 103 patients completed follow-up. The analysis revealed an interaction effect of preoperative cerebral ischemic injury and use of cardiopulmonary bypass on physical health (F = 9.07, P = .003) independent of age. No independent effects on health status were found of baseline magnetic resonance imaging or new cerebral lesions at 3 months. This study strongly suggests that the combination of preoperative cerebral ischemic injury and use of cardiopulmonary bypass can predict postoperative health status at 3 months. Cerebral magnetic resonance imaging might be a more specific indicator than age for preoperative assessment of vulnerability or resilience during rehabilitation after on-pump cardiac surgery.