Average visual improvement was 17.96% (95% CI, 16.39 to 19.53%) with 61.8% of eyes improving and 23.5% remaining stable with no adverse events occurring.Retinal implants are in the early stages of development and their use could be of benefit to many people with Visual impairment though implanting and maintaining an electrical device within the eye that interfaces with the optic nerve presents many challenges. An example of a device is made by Argus retinal prosthesis, the camera is an external device held on spectacles, the camera signal is processed and then fed via wires into the retina to terminate in some electrodes that interface with the optic nerve. References
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These methods have drawbacks, but give invasive estimations of the cardiac output, which can be used to make clinical decisions (e.g., cardiogenic shock, heart failure) to improve the persons condition.Cardiac catheterization can be used as part of a therapeutic regimen to improve outcomes for survivors of out-of-hospital cardiac arrest.Cardiac catheterization often requires the use of fluoroscopy to visualize the path of the catheter as it enters the heart or as it enters the coronary arteries. The coronary arteries are known as "epicardial vessels" as they are located in the epicardium, the outermost layer of the heart. The use of fluoroscopy requires radiopaque contrast, which in rare cases can lead to contrast-induced kidney injury (see Contrast-induced nephropathy). People are constantly exposed to low doses of ionizing radiation during procedures. Ideal table positioning between the x-ray source and receiver, and radiation monitoring via thermoluminescent dosimetry, are two main ways of reducing a persons exposure to radiation. People with certain comorbidities (people who have more than one condition at the same time) have a higher risk of adverse events during the cardiac catheterization procedure. These comorbidity conditions include aortic aneurysm, aortic stenosis, extensive three-vessel coronary artery disease, diabetes, uncontrolled hypertension, obesity, chronic kidney disease, and unstable angina. Left heart catheterization
Left heart catheterization (LHC) is an ambiguous term and sometime clarification is required:
LHC can mean measuring the pressures of the left side of the heart.