Superficial- and deep-tissue temperature increases in anesthetized dogs during exposure to high specific absorption rates in a 1.5-T MR imager

Superficial- and deep-tissue heating was measured in five dogs during high-specific-absorption-rate radiofrequency (RF) irradiation to see whether significant temperature changes could be produced by a 1.5-T clinical magnetic resonance imager. The RF power output employed was 6.3 times that required for routine imaging. Temperature probes were placed in both deep and superficial tissues, and temperatures were recorded before, during, and after exposure. In each dog, there was a linear temperature increase of several degrees during RF exposure; the maximal average change was 4.6 degrees C in the urinary bladder. The temperature increase was slightly greater in deep tissues than in superficial tissues. The calculated specific absorption rate, based on the temperature change, averaged 7.9 W/kg for all five dogs. These findings argue for continued caution in the design and operation of imagers capable of high specific absorption rates, particularly when they are used for imaging infants or patients with altered thermoregulatory capability.     

Aicardi syndrome: epilepsy surgery as a palliative treatment option for selected patients and pathological findings

The optimal treatment for medically refractory epilepsy in Aicardi syndrome (AS) is still unclear. Palliative surgical treatment, including vagus nerve stimulation and corpus callosotomy, has therefore been used. There is limited data on the role of resective epilepsy surgery as a treatment choice in patients with AS. Here, we describe the seizures, anatomo‐pathological findings, and neurodevelopmental outcome of palliative epilepsy surgery in two children with AS who had resective epilepsy surgery at the Cleveland Clinic. The related literature is also reviewed. Case 1 had a left functional hemispherectomy and was free of seizures and hypsarrhythmia for six months after surgery. Her gross motor skills improved after surgery. Outcome at 43 months was 1–3 isolated spasms per day. Case 2 had a right fronto‐parietal lobectomy. Her seizures improved in frequency and severity, but remained daily after epilepsy surgery. Neurodevelopment changes included improved alertness and recognition of caregivers. This patient died 21 months after epilepsy surgery of unclear causes. Surgical pathology in both cases showed focal cortical dysplasia associated with other findings, such as nodular heterotopia and polymicrogyria. Epilepsy surgery could be an alternative palliative treatment choice in selective cases of AS, but studies on a larger patient cohort are needed to identify the possible role of surgery in children with AS. The complexity of the pathological findings may offer an explanation for the severity of seizures in AS.     

Circadian patterns of generalized tonic-clonic evolutions in pediatric epilepsy patients

ObjectiveTo investigate the sleep/wake, day/night, and 24-h periodicity of pediatric evolution to generalized tonic–clonic seizures (GTC).MethodsCharts of 407 consecutive patients aged 0–21 years undergoing continuous video-EEG monitoring for epilepsy were reviewed for the presence of GTC evolution. Seizures were characterized according to 2001 ILAE terminology. Charts were reviewed for EEG seizure localization, MRI lesion, and for seizure occurrence in 3-h time blocks, out of sleep or wakefulness, and during the day (6 AM–6 PM) or night. Analysis was done with binomial testing. Regression models were fitted using generalized estimating equations with patients as the cluster level variable.Results71 patients (32 girls, mean age 12.63 ± 5.3 years) had 223 seizures with GTC evolution. Sleep/wake seizure distribution predicted tonic–clonic evolution better than time of day, with more occurring during sleep (p < 0.001). Tonic–clonic evolution occurred most frequently between 12–3 AM and 6–9 AM (p < 0.05). Patients with generalized EEG onset had more tonic–clonic evolution between 9 AM and 12 PM (p < 0.05). Patients with extratemporal focal seizures were more likely to evolve during sleep (p < 0.001); this pattern was not found in patients with temporal or generalized seizure onset on EEG. Patients without MRI lesions were more likely to evolve between 12 AM and 3 AM (p < 0.05), in the sleeping state (p < 0.001), and at night (p < 0.05). Logistic regression revealed that sleep and older patient age were the most important predictors of GTC evolution.ConclusionGTC evolution occurs most frequently out of sleep and in older patients. Our results may assist in seizure prediction, individualized treatment patterns, and potentially complication and SUDEP prevention.     

Excretory urography in the emergency department: utility of teleradiology

To test the feasibility of teleradiology for use with excretory urograms obtained in the emergency department in cases for suspected renal colic, radiographs from 43 patients were digitized, transmitted via standard phone lines, and viewed on a video monitor 2 miles distant. Diagnostic interpretations of the video image and the original radiograph were reviewed for degree of concordance. The video and film images of the 27 examinations showing obstruction were interpreted with 100% correlation. Agreement as to the site of obstruction was present in 93% of cases. Only two-thirds of renal and ureteral calculi seen on the radiographs were discerned on the video images, however. Teleradiology proved as useful for ongoing monitoring and modification of these examinations as for initial interpretation.     

Osteoarthritis of the facet joints: accuracy of oblique radiographic assessment

Sensitivity and specificity of lumbar spine radiography in the assessment of facet joint osteoarthritis were evaluated, with computed tomography (CT) as the standard. Two independent radiologists used a four-point scale to blindly grade facet joint osteoarthritis on oblique radiographs and transaxial CT scans obtained within an 8-month period in 50 consecutive patients with pain in the lower back. The L-3 to L-4, L-4 to L-5, and L-5 to S-1 facet joints were evaluated, and 68% appeared abnormal on CT scans, with 28% exhibiting moderate or severe disease. Interobserver agreement was high for conventional radiography (perfect agreement in 57% and agreement to within one grade in 39%) and still higher for CT (perfect in 63% and to within one grade in 35%). Receiver operating characteristic curve analysis indicated that oblique radiography was most accurate (55% sensitivity, 69% specificity) in distinguishing the presence from the absence of disease; in distinguishing absent or mild from moderate or severe disease, the specificity of oblique radiography was higher, at 94%, but its sensitivity was much lower, at 23%. Conventional radiography is a useful technique in screening for facet joint osteoarthritis but is insensitive compared with CT.     

Detection of colonic polyps on single-contrast barium enema study: emphasis on the elderly

A systems approach was employed to improve results of the single-contrast barium enema examination for detection of colonic polyps. Improvements were made in each of the following areas: radiographic-fluoroscopic equipment, fluoroscopic-television images, screen-film combinations, barium suspensions, examination techniques, imaging sequences, and quality controls. Radiologic-endoscopic correlation was undertaken for 137 colonic polyps seen endoscopically in 91 patients. The average age of the patients was 69 years. The sensitivity of the single-contrast examination for detection of all polyps was 80%. Polyps 5-9 mm in size were detected with 66% sensitivity, while 94% of polyps 10 mm or larger were detected. The results indicate that the sensitivity of a suitably performed single-contrast barium enema examination may approach that of the double-contrast study for the detection of colonic polyps, even in an elderly and infirm patient population.     

Qualitative analysis by interviews and video recordings to establish the components of a skilled low-cavity non-rotational vacuum delivery

Objectives  The objectives of this study were to define the components of a skilled low-cavity non-rotational vacuum delivery (occiput anterior, vertex at station +2 or below and less than 45-degree rotation from midline) and to facilitate the transfer of skills from expert to trainee obstetricians.
Design  Qualitative study using interviews and video recordings.
Setting  Two university teaching hospitals (St Michael's Hospital, Bristol, and Ninewell's Hospital, Dundee).
Participants  Ten obstetricians and eight midwives identified as experts in conducting or supporting operative vaginal deliveries.
Methods  Semi-structured interviews were carried out using routine clinical scenarios. The experts were also video recorded conducting low-cavity vacuum deliveries in a simulation setting. The interviews and video recordings were transcribed verbatim and analysed using thematic coding. The anonymised data were independently coded by three researchers and compared for consistency of interpretation. The experts reviewed the coded interviews and video data for respondent validation and clarification. The themes that emerged following the final coding were used to formulate a list of skills.
Main outcome measures  Key technical skills of a low-cavity non-rotational delivery.
Results  The final list included detailed technical skills required for conducting a low-cavity vacuum delivery. The combination of semi-structured interviews and simulation videos allowed the formulation of a comprehensive skills tool for future evaluation.
Conclusion  This explicitly defined skills list could aid trainees understanding of the technique of low-cavity vacuum delivery. This is an important first step in evaluating clinical competence in intrapartum procedures.