Control Of Refractive Error Through Ionically Driven Fluid Movements
Funder
National Health and Medical Research Council
Funding Amount
$208,600.00
Summary
Myopia affects about half the world's population with recent studies suggesting epidemic proportions among some Asian schoolchildren though we are not seeing this in Australia. Costs associated with detection, monitoring and optical correction of low and high myopia are huge. High myopes (15% with > 6D) also have a greatly increased risk of blindness between the ages of 30 and 50 years due to secondary disorders associated with impaired fluid balance (retinal and choroidal oedema, macula oede ....Myopia affects about half the world's population with recent studies suggesting epidemic proportions among some Asian schoolchildren though we are not seeing this in Australia. Costs associated with detection, monitoring and optical correction of low and high myopia are huge. High myopes (15% with > 6D) also have a greatly increased risk of blindness between the ages of 30 and 50 years due to secondary disorders associated with impaired fluid balance (retinal and choroidal oedema, macula oedema, retinal detachment and glaucoma). Currently there is no accepted pharmaceutical treatment for myopia though our studies in chick have provided the theoretical rationale and experimental data for a potential therapy and patent. This patent is now at the PCT stage and attests that changes in the abundance of the ions of the subretinal space control fluid movements across the retina to choroid and can be modulated therapeutically by diuretics to control fluid flow and hence axial growth and myopia. This application aims to take our current knowledge about fluid control in myopic chick into a mammalian model prior to preclinical trials in monkey. We anticipate it will take 1 year to establish the feasibility of diuretic control of experimentally induced myopic refractive errors in guinea pigs and the best drug and best the dosage range. These studies will contribute to the scientific understanding and bring the proposed pharmaceutical therapy for myopia in adults and children to a point of full commercialization. We believe that the results found in chick will have significance for early and late-onset myopia in humans as it is highly likely that the same mechanisms of ocular growth regulation operate throughout life.Read moreRead less
Assessment Of Bilateral Oedema By Bioelectrical Impedance Analysis
Funder
National Health and Medical Research Council
Funding Amount
$180,000.00
Summary
Swelling of tissue due to fluid accumulation, known as oedema, is one of the earliest signs of diseases such as kidney failure, burn injury or lymphedema. All of these are not uncommon conditions. Lymphedema, for example, is a common sequela of radiotherapy or surgery in the treatment of malignancies such as breast, uterine, and prostatic carcinoma. It is reported to occur in up to 40% of patients depending on the type of surgery and whether or not the patient received radiotherapy. It is estima ....Swelling of tissue due to fluid accumulation, known as oedema, is one of the earliest signs of diseases such as kidney failure, burn injury or lymphedema. All of these are not uncommon conditions. Lymphedema, for example, is a common sequela of radiotherapy or surgery in the treatment of malignancies such as breast, uterine, and prostatic carcinoma. It is reported to occur in up to 40% of patients depending on the type of surgery and whether or not the patient received radiotherapy. It is estimated that at any time 100000 women are suffering from post- mastectomy lymphedema in Australia alone. Treatment of breast cancer alone therefore, given the incidence of the disease, produces a large at-risk population. Add to this other causes of oedema and the magnitude of the problem becomes clearly apparent. The presence of chronic oedema is often a disfiguring and disabling disorder, usually accompanied by pain, recurrent infection, reduced mobility and impaired function. In acute oedema the problem often resolves with recovery from the underlying pathology. In chronic oedema, progression may be arrested by early intervention including complex physical therapy (exercise regimen, compression bandaging, and massage) which is effective in reducing limb volume, in improving the quality of life, function and body image of patients. Although the assessment of oedema is clearly of clinical importance, relatively few objective and accurate techniques for its measurement exist. Research conducted over the past decade by the applicants has pioneered the Use of Bioelectrical Impedance Analysis for the assessment of lymphedema. This study aims to translate this basic research into clinical practice. Sensitivity and specificity studies will establish normative and threshold values for impedance measurements that can be used as presumptive indicators of oedema. User friendly technology and equipment suitable for clinical use will be developed which should improve treatment therapies.Read moreRead less
Acoustic Blood Pressure Measurement On Implanted Biomedical Surfaces
Funder
National Health and Medical Research Council
Funding Amount
$184,687.00
Summary
Measurement of local blood pressure in is of great clinical importance. An application of particular interest is the pressure measurement in and around endoluminal stents grafts, which are used for the treatment of Abdominal Aortic Aneurysms (AAAs). These grafts are implanted by keyhole surgery and are used to reduce the pressure on the aneurysm walls so that the artery can revert to its more anatomically correct shape on a timescale of one to two years. If the seal between the graft and the art ....Measurement of local blood pressure in is of great clinical importance. An application of particular interest is the pressure measurement in and around endoluminal stents grafts, which are used for the treatment of Abdominal Aortic Aneurysms (AAAs). These grafts are implanted by keyhole surgery and are used to reduce the pressure on the aneurysm walls so that the artery can revert to its more anatomically correct shape on a timescale of one to two years. If the seal between the graft and the artery wall is not blood tight, then the aneurysm can become repressurised and may keep on expanding. Over time, an untreated, expanding AAA is likely to rupture with severe consequences for the patient. Thus a convenient, non-invasive means of measuring the pressure within the aneurysm and within the graft is highly desirable. In this proposal, we seek to produce a device that can be incorporated into the walls of the endoluminal graft, which can measure absolute pressure inside and outside the graft and where the pressure measurements can be obtained via standard acoustic or medical ultrasound equipment. To do this, we would use specially designed 'bubbles' which can be incorporated onto either side of the graft walls, where the resonant frequency of the bubbles provides a direct measurement of the pressure around the bubbles. Trials at the CSIRO have found that pressures can be measured to a resolution of better than 10 mmHg by using this technique on air bubbles in water. In this proposal, we wish to develop flexible, but semi-permanent bubbles that can be incorporated onto a biomedical implant surface. If such bubbles can be made, the researchers will use CSIRO-developed software and acoustic equipment such that local blood pressure can be measured in real time.Read moreRead less