Dengue Fever-Associated Maculopathy and Panuveitis in Australia.

Purpose. To describe a case of dengue fever-associated maculopathy and panuveitis to raise awareness of these ophthalmic complications of dengue in Australia in the light of recent increasing numbers of outbreaks from equatorial through to tropical Australia. Case Report. A 37-year-old Caucasian Australian male returning from Cambodia presented with a bilateral dengue fever-associated maculopathy with left panuveitis diagnosed clinically and haematologically. Automated perimetry revealed bilateral paracentral scotomas while optical coherence tomography demonstrated the maculopathies to be of the diffuse retinal thickening type in the right eye and acute macular neuroretinopathy (AMN) type in the left eye. He was treated conservatively with only topical steroids and cycloplegia and made a full clinical visual recovery. Conclusion. Our case study underscores the importance of the awareness of the ophthalmic complications of dengue fever as despite their rarity they can be potentially sight threatening. The incidence of these complications is likely to rise in Australia with increased global warming and the distribution of Aedes aegypti into subtropical Australia.

Amplitude scaling relationships of Burian-Allen, gold foil and Dawson, Trick and Litzkow electrodes.

The bipolar Burian-Allen electrode represents the International Society for Clinical Electrophysiology of Vision standard for recording the electroretinogram. With prolonged recording there is a high risk of corneal abrasion from the electrode, while alternatives such as gold foil electrodes or fibers represent less risk. The standards require that alternative electrodes be demonstrated to give equivalent waveform and amplitudes. Electroretinograms were recorded with the bipolar Burian-Allen electrode and four alternative electrode configurations: a unipolar Burian-Allen electrode, a bipolar and monopolar gold foil electrode and a Dawson, Trick and Litzkow fiber electrode with all other recording conditions identical. The results represent a guide for comparisons of electroretinograms between studies using these electrodes. Recordings were made from two subjects for all five electrode configurations and six additional subjects with unipolar gold foil and bipolar gold foil electrodes alone. Flash stimuli over a range of intensities from full intensity to -1.5 log units were used. Recordings were repeated in the one session and on a subsequent session to provide test-retest reliabilities. Significant (p < 0.0001) differences in b-wave amplitude resulting from electrode type and intensity were demonstrated. The unipolar Burian-Allen and unipolar gold foil electrodes produced the greatest amplitude responses. The alternatives to the bipolar Burian-Allen electrode were equally or more reliable. The Dawson, Trick and Litzkow electrode produced lower-amplitude response than the bipolar Burian-Allen electrode but was the only one with significantly greater between-session reliability.

Electromyography of arrow release in archery.

An electronic arrow movement detector was used to accurately locate the muscle activity associated with release of the arrow during shooting in archery. Digital computer analysis of the electromyograms from thirty shots for two archers facilitated an examination of the relationship between the measured activity of the muscles and their function during release. Changes present in the direct and integrated electromyograms of muscles acting at the wrist and elbow joints of the bow arm and the shoulder of the draw arm tended to anticipate the moment of arrow release. These changes would produce muscular force to reduce unwanted movement at this critical phase of the shot in the bow arm and initiate release of the bow string by the fingers. This study provides a detailed quantitative analysis of the muscular action of the technique and identifies possibilities for prevention of injury by improving the understanding of muscle action in shooting.