Profuse bleeding due to retinal tearing represents a common problem when working in the posterior chamber of the diabetic eye. If the traction and vibration associated with traditional vitrectomy tools could be eliminated, then many of their associated problems could also be removed. By investigating the tuning of laser energy in order to target the protein in the vitreous, rather than the bulk fluid, it is proposed that such a cutting device could be manufactured. A series of scans were performed on swine vitreous in order to determine its optical properties. A scanning spectrometer covering the region between 2.5 and 25 micrometers was used to scan both the vitreous and pure water samples. For each collagen scan, the water samples from either side were subtracted to give the absorption due to vitreous alone. It was found that there were several peaks of potential interest in the vitreous samples. As well as the water peak at around 3 micrometers, there was also a series of peaks between 6.2 and 6.5 micrometers. These latter bands represent absorption that is due to the proteins in the vitreous. Targeting these Amide bands could represent a possible method of targeting the laser energy without causing the collateral damage associated with high cutting or liquefaction rates. This could thus allow either higher aspiration rates while working in the center of the eye, or more precise removal of membranes in more delicate regions of the eye without any traction on the retina begin caused.
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