Rajanandini Muralidharan

Neurological Injury in Adults Treated With Extracorporeal Membrane Oxygenation

BACKGROUND Extracorporeal membrane oxygenation (ECMO) may be urgently used as a last resort form of life support when all other treatment options for potentially reversible cardiopulmonary injury have failed. OBJECTIVE To examine the range and frequency of neurological injury in ECMO-treated adults. DESIGN Retrospective clinicopathological cohort study. SETTING Mayo Clinic, Rochester, Minnesota. PATIENTS A prospectively collected registry of all patients 15 years or older treated with ECMO for 12 or more hours from January 2002 to April 2010. INTERVENTION Patients were analyzed for potential risk factors for neurological events and death using logistic regression and Cox proportional hazards models. MAIN OUTCOME MEASURES Neurological diagnosis and/or death. RESULTS A total of 87 adults were treated (35 female [40%]; median age, 54 years [interquartile range, 31]; mean duration of ECMO, 91 hours [interquartile range, 100]; overall survival >7 days after ECMO, 52%). Neurological events occurred in 42 patients who received ECMO (50%; 95% confidence interval [CI], 39%-61%). Diagnoses included subarachnoid hemorrhage, ischemic watershed infarctions, hypoxic-ischemic encephalopathy, unexplained coma, and brain death. Death in patients who received ECMO who did not require antecedent cardiopulmonary resuscitation was associated with increased age (odds ratio, 1.24 per decade; 95% CI, 1.03-1.50; P = .02) and lower minimum arterial oxygen pressure (odds ratio, 0.79; 95% CI, 0.68-0.92; P = .03). Although stroke was rarely diagnosed clinically, 9 of 10 brains studied at autopsy demonstrated hypoxic-ischemic and hemorrhagic lesions of vascular origin. CONCLUSION Severe neurological sequelae occur frequently in adult ECMO-treated patients with otherwise reversible cardiopulmonary injury (conservative estimate, 50%) and include a range of potentially fatal neurological diagnoses that may be due to the precipitating event and/or ECMO treatment.

Progressive Multifocal Leukoencephalopathy in Transplant Recipients

Transplant recipients are at risk of developing progressive multifocal leukoencephalopathy (PML), a rare demyelinating disorder caused by oligodendrocyte destruction by JC virus.

The clinical and radiological presentation of spinal dural arteriovenous fistula

Study Design. Retrospective consecutive case series. Objective. To assess the symptoms, neurologic signs, and radiologic findings in a large series of patients with myelopathy due to spinal dural arteriovenous fistula (SDAVF). Summary of Background. The clinical diagnosis of SDAVF is difficult because presenting symptoms and signs can be similar to those seen with spinal canal stenosis or peripheral nerve or root disorders. Methods. We reviewed 153 consecutive patients with SDAVF treated surgically at our institution between 1985 and 2008. Before surgery, all patients had detailed neurologic examination, 147 patients had spinal magnetic resonance imaging (MRI) and all but one, had spinal angiography. We evaluated associations between symptoms, physical signs, spinal cord T2 signal abnormality on MRI, and fistula level on angiogram. Results. Mean age was 63.5 years and 119 (77.8%) were men. Weakness and sensory changes are usually symmetric and ascend from the lower extremities. Presenting symptoms included leg weakness (74 patients, 48.4%), leg sensory disturbances (41 patients, 26.8%), pain involving back or legs (31 patients, 20.3%), and sphincter disturbances (6 patients, 3.9%). Worsening weakness with exertion was present in 66 (43.1%) patients and correlated with thoracic fistula location (P=0.04). Pinprick level was identified in 57 (37.3%) patients; L1 level (22.8%) was the most common, followed by T10 (19.3%). Fistula level (±2 levels) corresponded to pinprick level in only 40% of these patients. T2 signal abnormality involved the conus in 95% of our patients. Highest cord level of T2 signal hyperintensity (±2 levels) corresponded to pinprick level in 25% of cases. Conclusion. Leg weakness exacerbated by exercise, likely due to worsening hypertension in the arterialized draining vein, is a common manifestation of thoracic SDAVF. Although a sensory level is often found, it cannot reliably guide the level of imaging. Thus, the entire spine should be examined with MRI when an SDAVF is suspected.

Susac syndrome: clinical characteristics and treatment in 29 new cases

Background and purpose:  There are few clinical studies on the attempted treatments and outcomes in patients with Susac syndrome (SS) (retinocochleocerebral vasculopathy).

Worldwide reported use of IV tissue plasminogen activator for acute ischemic stroke

Background and Purpose Intravenous tissue plasminogen activator is the most effective treatment for acute ischemic stroke, and its use may therefore serve as an indicator of the available level of acute stroke care. The greatest burden of stroke is in low- and middle-income countries, but the extent to which intravenous tissue plasminogen activator is used in these countries is unreported. Summary of Review A systematic review was performed searching each country name AND ‘stroke’ OR ‘tissue plasminogen activator’ OR ‘thrombolysis’ using PubMed, Embase, Global Health, African Index Medicus, and abstracts published in the International Journal of Stroke (Jan. 1, 1996–Oct. 1, 2012). The reported use of intravenous tissue plasminogen activator was then analyzed according to country-level income status, total expenditure on health per capita, and mortality and disability-adjusted life years due to stroke. There were 118 780 citations reviewed. Of 214 countries and independent territories, 64 (30%) reported use of intravenous tissue plasminogen activator for acute ischemic stroke in the medical literature: 3% (1/36) low-income, 19% (10/54) lower-middle-income, 33% (18/54) upper-middle-income, and 50% (35/70) high-income-countries (test for trend, P < 0·001). When considering country-level determinants of reported intravenous tissue plasminogen activator use for acute ischemic stroke, total healthcare expenditure per capita (odds ratio 3·3 per 1000 international dollar increase, 95% confidence interval 1·4–9·9, P = 0·02) and reported mortality rate from cerebrovascular disease (odds ratio 1·02, 95% confidence interval 0·99–1·06, P = 0·02) were significant, but reported disability-adjusted life years from cerebrovascular diseases and gross national income per capita were not (P > 0·05). Of the 10 countries with the highest disability-adjusted life years due to stroke, only one reported intravenous tissue plasminogen activator use. Conclusions By reported use, intravenous tissue plasminogen activator for acute ischemic stroke is available to some patients in approximately one-third of countries. Access to advanced acute stroke care is most limited where the greatest burden of cerebrovascular disease is reported.

Prognostic value of clinical and radiological signs in the postoperative outcome of spinal dural arteriovenous fistula.

Study Design. Retrospective consecutive case series. Objective. To determine predictors of outcome in patients undergoing surgical treatment of spinal dural arteriovenous fistula (SDAVF). Summary of Background Data. Most previous studies assessing postoperative outcome in patients with SDAVF have been limited due to small population size, lack of sufficient information on presurgical variables, or short time of postoperative follow-up. Consequently, the most reliable predictors of functional outcome after treatment of SDAVF are not yet well established. Methods. Retrospective analysis of consecutive patients with SDAVF treated surgically between June 1985 and March 2008 in our institution. The Aminoff-Logue gait (G) and micturition (M) scores were used to stratify the degree of disability and the G + M score was used as the primary outcome measure. Demographics, clinical presentation, time to diagnosis, fistula level, presurgical motor and sphincter impairment, and magnetic resonance imaging findings were assessed as prognosticators for postoperative outcomes. Results. One hundred fifty-three patients were analyzed. Mean follow-up was 31 ± 36.2 months. Most patients were improved (44%) or stable (34%) upon the last follow-up. Among preoperative variables, worsening weakness with exertion was associated with a better G + M score at the last follow-up (P < 0.001) and presence of pinprick level was associated with a worse G + M score at the last follow-up (P = 0.020). On multivariable analysis, worsening weakness with exertion was associated with better outcome at the last follow-up, and higher G score at presentation and higher G + M score at discharge were associated with worse outcome at the last follow-up. Magnetic resonance images obtained postoperatively for 104 patients (mean, 19.1 ± 22.5 mo) showed complete resolution or improvement of the presurgical T2 signal abnormalities in 83.6% of cases. Changes in postoperative magnetic resonance image and fistula level did not correlate with functional outcomes. Conclusion. The degree of preoperative disability from SDAFV does not determine who will benefit most from surgery and even patients with severe deficits can improve after treatment. Patients with preoperative exertional claudication and without pinprick level on examination have greater chances of postsurgical improvement. Level of Evidence: 4

Studies on Structural, Spectral, and Optical Properties of Organic Nonlinear Optical Single Crystal: 2-Amino-4,6-dimethylpyrimidinium p-Hydroxybenzoate

2-Amino-4,6-dimethylpyrimidinium p-hydroxybenzoate (ADPHB), a novel organic material, was synthesized, and crystals were grown by slow evaporation solution growth method. The cell parameters and crystalline perfection of the grown crystal were studied by single crystal and powder X-ray diffraction analyses. The presence of various functional groups of the grown crystal was confirmed using Fourier Transform infrared spectral analysis. UV-Visible spectrum shows that ADPHB crystals have high transmittance in the range 305–900 nm. The refractive index and transient photoluminescence properties of the grown crystal were analyzed. The laser induced surface damage threshold, optical birefringence, and second harmonic generation efficiency of the grown crystal were studied.

Outcome of fulminant bacterial meningitis in adult patients

The objective of our study was to identify neurological factors associated with poor outcome in adult patients with fulminant bacterial meningitis.

Cervicomedullary Injury After Pneumococcal Meningitis With Brain Edema

OBJECTIVES To demonstrate a rare but potential mechanism of quadriplegia in a patient with fulminant pneumococcal meningitis complicated by severe intracranial hypertension. DESIGN Case report. SETTING Intensive care unit. PATIENT A 21-year-old man who presented with 3 days of headache, combativeness, and fever. INTERVENTION Antibiotics and steroids were initiated after lumbar puncture yielded purulent cerebrospinal fluid and streptococcus pneumoniae. RESULTS The patients course was complicated by severe cerebral edema necessitating intracranial pressure monitoring and intracranial pressure-targeted therapy. Within 5 days he developed quadriplegia and areflexia. Brain and cervical spine magnetic resonance imaging revealed patchy areas of T2 signal hyperintensity with associated gadolinium enhancement in the superior cervical spinal cord, cerebellar tonsils, and medulla. CONCLUSIONS Quadriplegia secondary to tonsillar herniation in fulminant meningitis is rare but should be considered in patients with acute quadriparesis after treatment of increased intracranial pressure. Magnetic resonance imaging signal changes and gadolinium enhancement may be demonstrated. Significant improvement of cord symptoms can be expected.

Posterior reversible encephalopathy syndrome is not associated with mutations in aquaporin-4

Posterior reversible encephalopathy syndrome (PRES) is characterized by acute reversible subcortical vasogenic edema that is typically bilateral and self-limiting. It preferentially affects posterior regions of the brain. Clinical manifestations include encephalopathy, seizures, headache, and cortical blindness. PRES may be precipitated by hypertensive crises such as eclampsia and by immunosuppressive agents. The pathophysiology of PRES is incompletely understood. Disordered cerebral autoregulation leading to protein and fluid extravasation is thought to be important.1 Other theories implicate endothelial dysfunction or vasospasm.2