Reading performance correlates with white‐matter properties in preterm and term children

Aim We used diffusion tensor imaging to investigate the association between white‐matter integrity and reading ability in a cohort of 28 children. Nineteen preterm children (14 males, five females; mean age 11y 11mo [SD 1y 10mo], mean gestational age 30.5wks (SD 3.2), mean birthweight was 1455g [SD 625]); and nine term children (five males, four females; mean age 12y 8mo [SD 2y 5mo], mean gestational age 39.6wks (SD 1.2), and mean birthweight 3877g [SD 473]). Method We tested whether fractional anisotropy in a left hemisphere temporoparietal region and in the corpus callosum correlates with birthweight and scores on the following three subtests of the Woodcock‐Johnson III Tests of Achievement: word identification, word attack, and passage comprehension. Results Preterm children had lower reading scores than a comparison group for all reading subtests (p<0.05). We found significant correlations between birthweight and fractional anisotropy in the whole corpus callosum (p=0.001), and between fractional anisotropy and reading skill in the genu (p=0.001) and body (p=0.001) of the corpus callosum. The correlation between reading skill and fractional anisotropy in a left temporoparietal region previously associated with reading disability was not significant (p=0.095). Interpretation We conclude that perinatal white‐matter injury of the central corpus callosum may have long‐term developmental implications for reading performance.     

A Simple Electrocardiographic Algorithm for Detecting Ventricular Tachycardia

The purpose of this study wus to determine whether a simple ECG algorithm could be developed for predicting susceptibility to ventricular tachyarrhythmias (VT) as defined by sustained spontaneous or inducible VT. Two different QT dispersion algorithms were determined by the difference between the longest and shortest QT interval measured in three orthogonal leads (I, aVF, V1; QTD3), and at least 11 of 12 leads (QTDl2) from the 12-lead ECG. These QT dispersion algorithms were investigated (with and without the QRS duration from the 12-lead EGG) and compared to the signal-averaged ECG (SAEGG) in order to determine their sensitivity and specificity for detecting VT. Only patients who underwent SAECC and were referred for programmed electrical stimulation were included in this study. A positive SAECG was defined by filtered QRS duration > 114 ms, and/or low amplitude signal duration > 38 ms, and/or root mean square voltage in the last 40 ms of < 20 μV. Sixty patients were enrolled in this study with a mean age of 63 ± 2 years. Eifty-five percent of the patients had coronary artery disease. A simple ECG algorithm consisting of the sum of QTD3 plus the QBS duration had a sensitivity and specificity of 90% and 63%. respectively, whereas the SAECG had a sensitivity and specificity of 60% and 63%. respectively (P = 0.022). We conclude that a simple EGG algorithm is more sensitive than the SAEGG for predicting VT. This algorithm combines two easily measured variables obtained from the 12-lead EGG, and can easily be performed without expensive computer equipment.     

Cystoscopy in women with recurrent urinary tract infection

OBJECTIVE: To investigate if women with recurrent urinary tract infection (UTI) warrant cystoscopy to exclude an abnormality of the lower urinary tract. This is particularly relevant given that non-invasive imaging has often been performed to exclude abnormality. Our further aims were to correlate imaging and risk factors with cystoscopic findings to determine their predictive value in finding pathology. PATIENTS AND METHODS: A database of women undergoing cystoscopy with recurrent UTI has been maintained at our institution for 10 years. We retrospectively examined this and patient records for patient demographics, and investigative and operative data. RESULTS: A total of 118 patients (mean 55 years) having recurrent UTI (mean 4.7 infections/year) were available. There were nine patients (8%) with significant abnormalities at cystoscopy: urethral stricture (six), bladder calculus (one), bladder diverticulum (one) and colovesical fistula (one). The negative predictive value (NPV) of imaging was 99% and significant (P < 0.01). Women with no risk factors for UTI had a NPV of 93% for normal cystoscopy (P > 0.05). The positive predictive value was low for imaging and risk factors in predicting cystoscopy findings. CONCLUSIONS: In our study, 8% of women had significant abnormalities detected during cystoscopy with most over 50 years. Women without risk factors for recurrent UTI and with normal imaging could have a cystoscopy omitted. Younger women are less likely to have pathology and this must be factored into decisions to perform cystoscopy.     

Does demographic entrapment challenge the two-child paradigm?

Local demographic entrapment has been discussed informally formany years, but is taboo to the UN agencies and to much of academia.There are also indications that the world as a whole may bedemographically trapped in that global per capita grain productionis falling. Arguments for and against recognizing entrapmentare discussed. Policy implications of entrapment are outlinedin the light of the 1994 International Conference on Populationand Development (ICPD). The case for a one-child world is argued.Carrying capacity, disentrapment, the two-child paradigm, abortion,Rwanda and North/South tensions are considered.     

Lidocaine's Effect on Defibrillation Threshold are Dependent on the Defibrillation Electrode System: Epicardial Versus Endocardial

Lidocaine's Effect on Defibrillation Depends on Lead System. Introduction: Epicardial and endocardial defibrillation electrode systems affect myocardial electrophysiology and sympathetic function differently. Thus, we postulate that antiarrhythmic drugs will interact with these electrode systems differently. Methods and Results: Defibrillation energy requirements (DER) at 20% (ED₂₀), 50% (ED₅₀), and 80% (ED₈₀), success were measured at baseline and during lidocaine (10 mg/kg per hour) or D5W treatment for epicardial and endocardial electrodes. Pigs were randomized to treatment (lidocaine or D5W) and electrode system, which resulted in four experimental groups: (1) epicardial electrode + D5W; (2) epicardial electrode + lidocaine; (3) endocardial electrode + D5W; and (4) endocardial electrode + lidocaine. ED₅₀ DER (mean ± SEM) values at baseline for groups 1–4 were 10.6 ± 1, 8.5 ± 1, 12.6 ± 1, and 12.3 ± 1 J, respectively. DER values for groups 1 and 3 during D5W were similar to baseline. Conversely, lidocaine increased ED₅₀ DER values from 8.5 ± 1 to 13.5 ± 2 J (P < 0.05) in group 2 animals (epicardial electrodes). When lidocaine was administered to group 4 animals (endocardial electrodes), however, ED₅₀ DER values remained similar to baseline values (12.3 ± 1 to 14.3 ± 2 J, P = NS). Lidocaine increased ED₅₀ DER values by 59% with the epicardial electrode system, which was significantly greater than the 16% increase with the endocardial electrode system (P < 0.05). Electrophysiologic response and electrode impedance were similar between electrode systems. Conclusion: Lidocaine increases DER values to a greater extent when using epicardial versus endocardial electrode system. Thus, drug-device interactions are dependent on the electrode system. These data suggest that the electrophysiologic milieu created by endocardial defibrillation mitigates the effects that lidocaine has on DER values.     

Our Approach to Minimize Risk of Epicardial Access: Standard Techniques with the Addition of Electroanatomic Mapping Guidance

Epicardial mapping and ablation is increasingly being performed for the treatment of complex arrhythmias. Right ventricular (RV) puncture remains the most common complication, with damage to surrounding non‐cardiac structures also a concern. We describe the standard techniques used in our lab essential for safe epicardial access, as well as a novel technique incorporating electroanatomic mapping (EAM) guidance. In a series of 8 patients referred for ventricular tachycardia ablation, an RV endocardial voltage map was created using EAM systems. EAM images were fused with preprocedure CT scans when available. A 17G Tuohy needle was integrated with the EAM system by attaching the needle to sterile electrode clamps. EAM location points were used in conjunction with standard access techniques until epicardial access was obtained. Epicardial access was successfully obtained in 8/8 (100%) patients. Successful access without RV puncture was achieved in 7/8 (88%) cases. This proof of concept study demonstrates that EAM systems can be used as an adjunct to standard access techniques to visualize and facilitate pericardial access.