Technical aspect of CT angiography of lower extremities.

Objective: To assess the less invasive technique of CT angiography for evaluation of lower extremity arteries with nonionic water soluble iodinated contrast medium. Methods: One hundred thirty patients underwent a CT angiography of lower extremity using smart prep technique above the iliac creast 1 inch. and the following parameters: Helical, Rotation time : 0.8 seconds, Rotation length : full, Detector configuration : 16X1.25 mm, Helical thickness : 1.25, Pitch : 1.375:1, Speed : 27.50 mm/rotation, Beam collimation : 20 mm, Image interval : 1.0 mm, Gantry tilt : 0.0, SFOV : large, X-ray energy 140 kV, 260 mA. Results: The data of CT Acquisition and Contrast Medium Parameters were Scanning coverage (mm): 1040 ฑ 88, Scanning duration (sec): 33+ 5, Number of transverse sections: 1063+ 348 iodine dose (g): 89.8+ 5.3, Concentration of contrast medium(mg/ml): 356.7+ 24.4, Volume of contrast medium (ml): 120+ 0, Contrast medium injector rate (ml/sec): 4+ 0, Injection duration (sec): 30+ 0, Scanning -to-injection duration ratio: 1.08+ 0.2, Delay between contrast medium initiation and scanning (sec): 26+ 5.3. Conclusion: The conventional study for lower extremity arteries is conventional angiography which is invasive method. This method required admission and absolute bed rest at least 8-12 hours after procedure. The CT angiography takes advantage over conventional angiography, including 3D volumetric analysis, minimally invasive vascular opacification and depiction of mural calcium. The fastest and more slices of current generation of 16 slices multidetector CT scanner is possible to study entire length of lower extremities.

Childhood onset myasthenia gravis.

The authors share experiences in taking care of 27 cases of childhood onset myasthenia gravis (MGS). In all cases, the diagnosis was confirmed by a combination of clinical examination and Neostigmine test. The majority (92%) had localized ocular myasthenia with median onset of symptoms at 33 months of age. About 24 per cent of them progressed to generalized MGS. A few (8%) presented with respiratory failure that required ventilatory support with onset of symptoms at about 22 months. Thymectomy was performed in 10 cases. Complete and partial remissions were achieved in about 70 per cent and 26 per cent of cases respectively with the combination of an immunosuppressant (azathioprine) and a Cholinesterase inhibitor (pyridostigmine). None experienced a myasthenic crisis with proper management and good follow-up using the above combinations.

Prevalence of migraine and headache among school children in Bangkok.

To determine the prevalence and risk factors of migraine and headache among school children in Bangkok. Methods: We carried out a community-based questionnaire survey, using the IHS diagnostic criteria, in 10 schools in Bangkok. The sensitivity and specificity of the questionnaire used in this study were 47.05% and 94.12% respectively. Two groups of school children, first and seventh grade students, were selected in order to determine the influence of age on the prevalence of migraine. The questionnaire also contained questions regarding risk factors such as family history of migraine, travelling time between school and home, mode of communication, school hours, and sleep duration at night. Results: The response rates were 23.48% for the first grade students, and 100% for the seventh grade students. The prevalence of migraine in the 821 first grade students that responded was 0.37%, with 0.6% in boys and 0.3% in girls. From the total of 3,547 seventh grade students that were studied, there were 169 children (4.77%) who met the criteria of migraine by IHS, 58 males (3.11%) and 111 females (6.6%). Risk factors that increased the occurrence migraine were a positive family history of migraine, female sex, stress due to travelling time to school of more than 2 hours, and less sleeping time. Conclusion: The prevalence of migraine of both age groups in this study was lower than studies from western countries. This could be due to a racial difference as well as the low sensitivity of the questionnaire. Besides the positive family history of migraine and less sleep duration at night, stress due to long hours of travelling between school and home was also an important triggering factor of migraine of school children in Bangkok.