RetGen

Researchers from The University of Auckland are about to begin a study to find how to better help blind and vision-impaired people manage the chronic sleeping disorders many face.

Dr Guy Warman, a lecturer at the Department of Anaesthesiology in the Faculty of Medical and Health Sciences is leading the study. He says they will investigate the prevalence of disturbances in the circadian rhythms of blind people, and how the hormone melatonin is being used to treat this.

"Although the primary problem associated with blindness is loss of vision, a secondary problem which can have a major impact on the health and well-being of blind people is the disruption of their sleep-wake cycles. This problem results from the inability of light to adjust their internal biological clock to a period 24 hours. As a result they can have disrupted sleep at night".

The study is funded by a grant from the Health Research Council of New Zealand and is being carried out in association with the Royal New Zealand Foundation of the Blind (RNZFB).
'Study to investigate sleep disturbances in blind and vision-impaired' (University of Auckland media release at Scoop, 25 October 2005).

"Our experience is limited by the small number of patients and the very short follow-up, but a rapid biologic effect is observed," Dr. Avery said. "It seems to penetrate the retina sufficiently for these effects."

He added that prospective clinical trials are needed to assess the safety and efficacy of bevacizumab. He noted that the long-term safety of this agent is not known.
'Intravitreal Bevacizumab (Avastin) Holds Promise for Retinal Vascular Diseases: Presented at AAO' (Doctor's Guide, 26 October 2005).

The differences between the various studies and whether there is a connection between AMD and cataracts "needs to be explained," said Frederick Ferris III, MD, Clinical Director, Epidemiology and Clinical Research, National Eye Institute, Bethesda, Maryland, United States.
'AREDS Findings Suggest Cataract Surgery Not Associated with Progression to Neovascular AMD: Presented at the AAO'(Doctor's Guide, 26 October 2005).

The immediate effect of the procedure is to reduce the plasma viscosity by 15% to 18%, explained Dr. Ronald Danis, Professor of Ophthalmology, University of Wisconsin, Madison, Wisconsin, United States. It is also believed to remove serum oxidative species that could accumulate in the Bruch's membrane and cause progressive damage to the neurons and retinal pigmented epithelium.
'Blood Filtration System a Novel Approach to Treating Age-Related Macular Degeneration: Presented at AAO' (Doctor's Guide, 21 October 2005).

Dr. Rosenfeld and colleagues studied 40 patients who had severe AMD and who received a mean of 1.8 injections of Avastin each as salvage therapy.

Results show a mean decrease in retinal thickness of 104 microns, from 332 microns at baseline to 228 microns.

Patients also had an improvement in visual acuity, from a mean of 20/160 to 20/125, which corresponds to an increase of one line of visual acuity in 40% of subjects, Dr. Rosenfeld said.
'Controversial Study Uses Avastin (Bevacizumab) to Treat Age-related Macular Degeneration: Presented at AAO' (Doctor's Guide, 18 October 2005).

"One of the magical moments was when we first arrived in the jungle.

"It was about 5pm and it suddenly got dark and then for the first time we could hear all around us these insects and birds, the whole jungle came to life.

"I was completely in awe of nature, sleeping in hammocks with the air blowing around me."
'Crossing the jungle in a wheelchair' (BBC News Health, 8 October 2005).

Kobayashi said visually impaired people could excel at rock climbing because they can feel their way up the wall with their hands, moving as slow or fast as they like, but remain safe due to a lifeline.

"Free climbing doesn't need special rules for the handicapped," Kobayashi said. "Some people learn faster than those who are not handicapped."
'Visually impaired climber gives everyone lift' (The Daily Yomiuri, 10 October 2005).

Called TheraMac(TM), it delivers minute amounts of biocurrent to the retina through a probe that touches the skin around the eye. The total time for treating one eye is approximately 15 minutes. A series of clinical trials have been completed to date.
'Acuity Medical Focuses on Treatment for Age-Related Macular Degeneration' (Acuity Medical media release at Yahoo! Finance, 3 October 2005).