Computed Tomography Angiography Quantification of Intracranial and Extracranial Vascular Narrowing in Ischemic Stroke: Differences Between Patients With and Without Illicit Drug Use.

OBJECTIVE: Previous studies have linked illicit drug consumption and stroke. The purpose of this study is to identify specific imaging findings depicted on computed tomography angiography on patients with illicit drug-associated stroke. METHODS: This is a retrospective case-control study that included ischemic stroke patients. Subjects who tested positive for cocaine or marijuana were considered as cases, while patients who tested negative were included as controls. Matching of the controls was carried out based on the presence of stroke risk factors. A previously validated scale was used to calculate narrowing scores through computed tomography angiography. Comparison between cases and matched controls was evaluated by paired t test for age and body mass index, and by Wilcoxon signed rank test for intracranial, extracranial, and total scores. RESULTS: One hundred seventy-four patients were included in the study, 87 subjects for each group. Because of matching, baseline status differed only on body mass index, with a greater proportion of obese subjects among controls ( P < 0.016). Subgroup analysis demonstrated that it is more likely to find any intracranial abnormality among cocaine consumers when compared with controls ( P = 0.041). CONCLUSIONS: By using computed tomography angiography, we found that stroke patients with history of cocaine consumption had a higher incidence of intracranial circulation narrowing compared with matched controls.

Magnetic resonance imaging-related programmable ventriculoperitoneal shunt valve setting changes occur often.

PURPOSE: Patients with programmable ventriculoperitoneal (VP) shunt valves undergo multiple skull radiographs to evaluate for setting changes resulting from MRI. Our purpose was to determine the rates of inadvertent, MRI-related, programmable VP shunt valve setting changes. MATERIALS AND METHODS: In this retrospective cohort with a study period of January 2015-December 2018, we reviewed the pre- and post-MRI skull radiographs of patients with programmable VP shunts and collected the following data: Demographics, commercial type of the valve used, magnetic field strength of the MRI device used, and whether a setting change occurred. We used the chi-square test to identify variables associated with valve setting change. RESULTS: We identified 210 MRI exposure events in 156 patients, and an MRI-related valve setting change rate of 56.7%. The setting change rate was significantly higher with higher magnetic field strength (p = 0.03), and with Medtronic Strata™ valves compared to Codman Hakim™ valves (p < 0.0001). CONCLUSION: Inadvertent, MRI-related shunt valve setting changes are frequent with valves that lack a locking mechanism. Therefore, we suggest that when feasible, the clinicians could opt to manually reprogram the valves after the MRI to the preferred setting without the need for pre- and post-MRI radiographs. We believe that this protocol modification could help reduce ionizing radiation exposure and cost. Manufacturers may consider incorporating locking mechanisms into the design of such devices in order to reduce the unintended setting change rates.

Non-contrast head CT-based thrombolysis for wake-up/unknown onset stroke is safe: A single-center study and meta-analysis.

BACKGROUND: Recent studies have shown that tPA can be safely administered past the standard 4.5 h window with good outcomes when selected with multi-model imaging, which is often lacking outside of comprehensive stroke centers. AIM: We aim to analyze the safety and outcomes of wake up/unknown onset (WUS/UNK) patients treated based on non-contrast head CT (NCCT) at our institution and in the literature. METHODS: Suspected stroke patients from January 2015 to December 2018 receiving tPA within 4.5 h (standard window-SW) and with WUS/UNK based on NCCT and clinical-imaging mismatch were identified. We compared baseline characteristics, tPA metrics, and outcome data, with primary outcome as symptomatic intracerebral hemorrhage (sICH). A meta-analysis was performed evaluating NCCT-based treatment of WUS/UNK patients. RESULTS: Of 1827 patients treated at our hub or through telestroke, 93 underwent WUS/UNK-based treatment. There was no statistical difference in sICH between WUS/UNK and SW: 1% vs. 4% (OR 0.3; 95% confidence interval 0.0-1.9). 90-day modified Rankin scale outcomes were similar between SW and WUS/UNK-treated patients. Seven studies encompassing 485 WUS/UNK patients were included in a pooled analysis with a 2.1% incidence of sICH. In our meta-analysis, three studies compared NCCT-based treated WUS/UNK patients with SW patients with no difference in rate of hemorrhage: 2.1% vs 3.4% (OR 1.01; 95% confidence interval 0.45-2.28). INTERPRETATION: Our single-center analysis and meta-analysis suggest that tPA can be safely administered based on NCCT with comparable rates of sICH for select WUS/UNK stroke patients.

Wisdom Tooth's Revenge: Retropharyngeal Abscess and Mediastinitis after Molar Tooth Extraction.

Retropharyngeal abscess is potentially associated with high morbidity and mortality as a result of its direct anatomical connection with the mediastinum. Therefore, knowledge of the relevant anatomy is essential for recognizing the presence and extent of disease in a timely manner. In this case report, we aim to review the pertinent anatomy and patterns of spread of infection from a full blown deep neck space infection to result in mediastinitis and empyema.

Early Conventional MRI for Prediction of Neurodevelopmental Impairment in Extremely-Low-Birth-Weight Infants.

BACKGROUND: Extremely-low-birth-weight (ELBW; ≤1,000 g) infants are at high risk for neurodevelopmental impairments. Conventional brain MRI at term-equivalent age is increasingly used for prediction of outcomes. However, optimal prediction models remain to be determined, especially for cognitive outcomes. OBJECTIVE: The aim was to evaluate the accuracy of a data-driven MRI scoring system to predict neurodevelopmental impairments. METHODS: 122 ELBW infants had a brain MRI performed at term-equivalent age. Conventional MRI findings were scored with a standardized algorithm and tested using a multivariable regression model to predict neurodevelopmental impairment, defined as one or more of the following at 18-24 months' corrected age: cerebral palsy, bilateral blindness, bilateral deafness requiring amplification, and/or cognitive/language delay. Results were compared with a commonly cited scoring system. RESULTS: In multivariable analyses, only moderate-to-severe gyral maturational delay was a significant predictor of overall neurodevelopmental impairment (OR: 12.6, 95% CI: 2.6, 62.0; p < 0.001). Moderate-to-severe gyral maturational delay also predicted cognitive delay, cognitive delay/death, and neurodevelopmental impairment/death. Diffuse cystic abnormality was a significant predictor of cerebral palsy (OR: 33.6, 95% CI: 4.9, 229.7; p < 0.001). These predictors exhibited high specificity (range: 94-99%) but low sensitivity (30-67%) for the above outcomes. White or gray matter scores, determined using a commonly cited scoring system, did not show significant association with neurodevelopmental impairment. CONCLUSIONS: In our cohort, conventional MRI at term-equivalent age exhibited high specificity in predicting neurodevelopmental outcomes. However, sensitivity was suboptimal, suggesting additional clinical factors and biomarkers are needed to enable accurate prognostication.

Identification of HIBCH gene mutations causing autosomal recessive Leigh syndrome: a gene involved in valine metabolism.

BACKGROUND: Leigh syndrome is a progressive neurodegenerative disorder with usual onset of symptoms during the first year of life. The disorder has been associated with mutations in over 30 genes. This difficulty with genetic heterogeneity makes whole exome sequencing a more cost-effective approach for investigation of etiology. PATIENT AND RESULTS: We describe an individual with typical Leigh syndrome who was found to have compound heterozygous mutations in the gene HIBCH (3-hydroxyisobutyryl coenzyme A hydrolase), an enzyme involved in the catabolism of valine. She exhibited significant clinical improvement after a valine-restricted diet. CONCLUSIONS: A subset of patients with uncharacterized Leigh syndrome present with specific biochemical abnormalities. This report highpoints the challenges and restrictions of routine metabolic testing and features the recognition of inborn errors of metabolism as potential treatable causes of Leigh syndrome.

Automatically quantified diffuse excessive high signal intensity on MRI predicts cognitive development in preterm infants.

BACKGROUND: Cognitive and language impairments constitute the majority of disabilities observed in preterm infants. It remains unclear if diffuse excessive high signal intensity on magnetic resonance imaging at term represents delayed white matter maturation or pathology. METHODS: We hypothesized that diffusion tensor imaging-based objectively quantified diffuse excessive high signal intensity measures at term will be strong predictors of cognitive and language development at 2 years in a cohort of 41 extremely low birth weight (≤1000 g) infants. Using an automated probabilistic atlas, mean diffusivity maps were used to objectively segment and quantify diffuse excessive high signal intensity volume and mean, axial, and radial diffusivity measures. Standardized neurodevelopment was assessed at 2 years of age using the Bayley Scales of Infant Development, third edition. RESULTS: Thirty-six of the 41 infants (88%) had complete developmental data at follow-up. Objectively quantified diffuse excessive high signal intensity volume correlated significantly with cognitive and language scores at 2 years (P < 0.001 for both). The sum values of the three diffusivity measures in detected diffuse excessive high signal intensity regions also correlated significantly with the Bayley scores (r(2) 34.7%; P < 0.001 for each). Infants in the highest quartile for diffuse excessive high signal intensity volumes had scores between 19 and 24 points lower than infants in the lowest quartile (P < 0.01). When diagnosed subjectively by neuroradiologists however, Bayley scores were not significantly lower in infants with extensive diffuse excessive high signal intensity. CONCLUSIONS: These findings lend further evidence that diffuse excessive high signal intensity is pathologic and that objectively quantified diffusion-based diffuse excessive high signal intensity volume at term is associated with cognitive and language impairments. Our approach could be used for risk stratification and early intervention for such high-risk extremely preterm infants.