It is now well established that clinically stable patients with relapsing-remitting multiple sclerosis have ongoing disease activity when evaluated by serial gadolinium-enhanced (Gd-DTPA) magnetic resonance imaging (MRI) scans. Despite this, the relationship between clinical disease and MRI lesions, though suspected, has not been extensively documented. The relationship between Gd-DTPA MRI lesions and clinical disease was examined in this study of 9 patients with mild relapsing-remitting multiple sclerosis (Expanded Disability Status Scale [EDSS] < 3.5) who had 24 to 37 monthly Gd-DTPA MRI scans, neurological examinations, and EDSS score assignments. The area and frequency of Gd-DTPA lesions were examined during months with and without clinical worsening as measured by EDSS. Forty-one episodes of clinical worsening were noted during the study. A significant association was observed between these periods of clinical worsening and MRI parameters, including increases in total number, number of new lesions, and the total area of enhancement. Logistic regression analysis showed a significant effect of the number and area of Gd-DTPA MRI lesions on both the onset and continuation of clinical worsening, confirming an important relationship between clinical disease and an increase in cerebral Gd-DTPA MRI activity. A relationship with long-term disability was suggested, but cannot be confirmed without longer follow-up of these patients.

Patients with severe acute chest syndrome (ACS) requiring endotracheal intubation and erythrocytopheresis are at increased risk for neurologic morbidity. This study examines patients with sickle cell disease who developed severe episodes of ACS, leading to endotracheal intubation, ventilatory support for respiratory failure, and erythrocytapheresis. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) studies, a neurologic examination by a pediatric neurologist, and cognitive testing were done in all patients. Five consecutive patients, aged 3 to 9 years, were identified with severe ACS. All patients developed neurologic complications resulting from ACS episodes, including seizures (n ‫؍‬ 2), silent cerebral infarcts (n ‫؍‬ 3), cerebral hemorrhage (n ‫؍‬ 2), and

Silent cerebral infarcts are brain lesions evident on magnetic resonance imaging (MRI) in individuals with an otherwise normal neurologic history and examination. 1,2 Silent cerebral infarcts are the most prevalent form of brain injury in children with sickle cell disease, with a rate of approximately 15% in children with hemoglobin SS by 12 years of age. 2,3 Silent cerebral lesions frequently appear as small lesions in the cortex, deep white matter, and basal ganglia. 4 When followed prospectively, children with sickle cell disease and silent cerebral infarcts are at a high risk for additional cerebral tissue damage. Silent cerebral infarcts are associated with approximately a 14-fold increase for subsequent overt stroke over a 5-year period. 5 In addition, the number and size of lesions have been noted to increase over time in children with silent infarcts who do not develop overt stroke. 6 By the age of 18 years, the rate of silent cerebral infarcts increases, with an estimated prevalence of 23%. 6 Both silent cerebral infarcts and overt stroke lead to decrements in cognitive functioning. 2,3,7-9 Overt stroke, however, is associated with worse cognitive functioning than silent cerebral infarcts. 2,3 Therefore, the additional occurrence of stroke in children with silent infarcts would be expected to have a significant impact on cognitive functioning. The effect of additional injury from progressive silent infarcts is less clear. It is possible that the initial injury associated with silent infarcts leads to decrements in cognitive functioning and that additional silent injuries have little added impact. Alternately, it is also possible that the location of silent infarcts is the predominant cause of cognitive deficits; thus, indices of lesion volume would not necessarily relate to cognitive outcome.Direct assessment of whether new silent cerebral infarcts are associated with greater cognitive impairment would require a longitudinal study of several hundred children receiving MRI surveillance and cognitive assessments. To provide a preliminary test of the hypothesis that the amount of tissue loss in silent cerebral infarcts relates to cognitive functioning, we evaluated the volume of cerebral lesions in children with silent cerebral infarcts secondary to sickle cell disease and related this to measures of cog- Original Article ABSTRACTThe effect of increased tissue injury in children with sickle cell disease and silent cerebral infarcts is not known. We determined the relationship between the extent of injury and IQ scores in children with silent cerebral infarcts. Participants were 27 children with sickle cell disease who had received magnetic resonance imaging. Children were divided into three groups: group 1, small lesion volume (n = 9, < 6.8 cm 3 ); group 2, large lesion volume (n = 9; > 6.8 cm 3 ); and group 3, no cerebral infarcts (n = 9). The Wechsler Full-Scale IQ was significantly lower for group 2 (mean = 76.1) when compared with group 1 (mean = 87.7) or group 3 (mean = 89.9). In children with silent c...

The primary objective of this study was to improve the educational success of children with sickle-cell disease (SCD) and cerebral infarcts. A prospective intervention trial was conducted; a multidisciplinary team was created to maximize educational resources for children with SCD and cerebral infarcts. Students were evaluated systematically before and after the intervention. A baseline evaluation was completed assessing the presence of an Individualized Education Plan (IEP), grade retention in school, and days absent from school in the year preceding the intervention. A postintervention assessment occurred 2 years later for these same measurements. At baseline, 74% (17 of 23) of the students were receiving IEPs. Two years later, 87% (20 of 23) students received IEPs (p = .34). Despite the intervention, the rate of children retained in their school grade increased from 0.6 per 100 years in school at baseline to 1.7 per 100 years, 95% CI (-3.86, 1.49). The school absenteeism rate did not significantly change after the intervention; the average days absent per student rose from 15.5 to 22.5, (p = .05). The multidisciplinary team effort alone was insufficient to decrease grade retention and absenteeism rate. Further support, from either the parents or school administration, is needed to increase education attainment of students with cerebral infarcts.