Identification of predictors of cerebrovascular infarcts in patients with tuberculous meningitis.

Background: Tuberculous meningitis (TBM) remains common in developing countries. Cerebrovascular infarct (CI) in TBM occurs in 15%-57% of patients. Literature regarding the predictors of central nervous system (CNS) infarct in patients with TBM is scanty, and the outcome of these events is unknown. The aim of this study is to evaluate the predictors of CI among patients with TBM at a tertiary care center in South India and to compare the impact of CI on the prognosis and outcomes in terms of mortality and morbidity. Methods: All patients who were confirmed to have TBM and CNS infarcts/stroke were included in this study retrospectively. Forty-six patients had appropriate imaging, and they were enrolled in the study as cases. Patients without infarct were matched with age and sex as controls. Details of the course of the disease, the extent of CNS involvement, and treatment were compared between the two arms. Results: The mean age of patients with and without infarct was similar. The presence of basal meningeal inflammation, hydrocephalus, focal neurological deficit, and cranial nerve palsy, was higher in patients with infarct. Independent predictors of infarcts in a patient with TBM were Medical Research Council (MRC) staging of II or more, presence of focal neurological deficit, cranial nerve palsy, and presence of hydrocephalus, meningeal enhancement on neuroimaging. Presences of infarcts were independently associated with a higher odds ratio of 2.58 for poor outcome, 4.48 for a longer duration of hospital stay, and odds ratio of 8.85 for the requirement of multiple hospitalizations. Conclusion: CI involvement in TBM has higher morbidity, with longer stay, recurrent admission.

Cerebrovascular injury in cryptococcal meningitis.

Background Cryptococcal meningitis continues to be one of the common causes of chronic central nervous system infection worldwide. Individuals with cryptococcal meningitis can occasionally present with small vessel vasculitis causing infarcts primarily in the basal ganglia, internal capsule, and thalamus. Literature regarding patterns of cerebrovascular injury among patients with cryptococcal meningitis is scanty, and outcome following these vascular involvements is unknown. Aim To study the clinical profile, imaging findings, and details of vascular territory involved among patients admitted with cryptococcal meningitis and central nervous system infarct in a tertiary care center from India. And to compare the outcomes of patients of cryptococcal meningitis with or without central nervous system infarcts in terms of mortality and morbidity, Methodology A total of 151 patients with microbiologically proven cryptococcal meningitis over a time span of 11 years were retrospectively enrolled into the study. Of these, 66 patients met the inclusion criteria of having appropriate imaging of the brain. The presence of infarct in the imaging was analyzed by two independent radiologists. Patterns of central nervous system involvement and types of vascular injury were ascertained based on radiological parameters. Clinical parameters and outcomes of patients with and without infarcts were compared. Results Twenty (13%) of these patients had evidence of central nervous system infarcts on imaging. The mean age of patients with and without infarcts was 41 years and 38 years, respectively. Male predominance was present among both the groups. The presence of fever, neck stiffness, positive blood culture, and hydrocephalus in central nervous system imaging was similar among patients with or without infarct. Longer duration of illness, low sensorium at the time of presentation, low Glasgow Coma Scale score, presence of meningeal inflammation, cryptococcomas, and basal exudates in imaging were higher in patients with infarct. All the infarcts were of the lacunar type. Sixty percent of the cerebrovascular infarcts were acute in nature, 50% of these being multiple. Unilateral infarcts were seen in 70% of the patients. The most common site of infarct was the basal ganglia, others being distributed over the thalamus, frontal, temporal, parieto-occipital regions in the descending order. The presence of neurovascular involvement in the form of infarcts to the risk of morbidity and mortality had an odds ratio of 9.1 and 2.6, respectively. Conclusion Neurovascular involvement in chronic cryptococcal meningitis is a rare entity. These tend to present as multiple lacunar infarcts. Mortality and morbidity associated with these patients is higher when compared to patients who do not have infarcts. This result suggests that vascular injury plays a role in predicting outcome of patients with cryptococcal meningitis. Future studies are needed to understand the mechanism by which vascular events (infarcts) occur and result in poor outcome.

Sensory input from the moving hand influences saccadic eye movements during reading.

Reading involves saccadic eye movements. Measured reading time and the number of mistakes made while reading reflect the speed and accuracy of the saccades in target localization, if all other factors influencing these parameters are kept constant. The observed phenomenon that reading a book is easier when it is held in an individual's hand than when it is not, especially when movement of the reading text occurs while travelling in a vehicle, raises the question of the role of sensory input from the moving arms in guiding saccades in the direction in which the text is moved. To address this question, 12 healthy subjects (6 males and 6 females), aged 19-21 years took part in this study where reading time and the number of mistakes made while reading a non-moving standardized printed text was noted. Similar printed texts were read by the subjects while mechanically moving them at different fixed speeds in the horizontal plane, with and without the subject's arms moving with the text. At each speed, the reading time recorded when the subject's arms moved with the text was significantly lesser than when they did not (P<0.05). The number of mistakes made were significantly more when not moving the arms than when moving them with the text, at higher speed of text movement (P<0.05). The results indicate that sensory input from the passively moving arms guided saccades in the direction of movement of the text during reading.