What makes the problem more challenging is the difficulty of measuring the intraocular pressure accurately in an eye with a KPro. In the Boston KPro the stiff back plate prevents measurements based on indentation of the cornea, even in its periphery. Scleral tonometry or the use of any device acting through the lids has been highly unreliable due to often distorted or scarred tissue arrangement. Despite all of variances, finger palpation over the upper lid with the patient looking down has been shown to be the best approach to gross judgment of the IOP (Melki, Lopez and Dohlman, 2009).
The KPros are manufactured to match the refractive need of the individual patient and, therefore, a substantial inventory is required to rapidly supply a device of the desired dimensions. For the eye that is pseudophakic and approximately emmetropic, and where the IOL is left in place at surgery, a single standard power is chosen for the manufacture. For aphakic eyes of different axial lengths, devices with a varying degree of power are made in order to match a patient's needs as closely as possible. Therefore, the axial length of the individual aphakic patient is always ask for from the surgeon in order to allow the choice of a KPro that in theory best matches the dioptric requirement of the eye which is being operated on (Dohlman, Harissi-Dagher and Graney, 2007).
Indications that a patient is suitable for the Boston Keratoprosthesis include:
Two failed grafts, with poor prognosis for further grafting
Vision less than 20/400 in the affected eye
No end-stage glaucoma or retinal detachment.
The one-step that is performed in this surgery is much simpler than the procedure that is used in other Keratoprosthesis forms. Even though general anesthesia is recommended, the current trend is...
Night time implies very low levels of light and therefore darkness. In this period, the human eye relies fully on the rod physiology so it no longer searches for color and alters our interpretation of the external environment by reducing levels of detail. Some scientists have estimated that our visual acuity during scotopia is around a scale of 20/200. Modern inventions of artificial light have helped man speed the recovery
The idea that a healthy lawyer is a more worthy citizen than a sick alcoholic is inherently biased and unacceptable in our society. Often, as in the keratoplasty case, there are legitimate reasons for wanting to give a rare, valuable transplant to a healthy individual rather than to a sick one. The alcoholic would appear a waste of time in the eyes of the medical system if he is denied
S. (Levine, 2008). One of the paradoxes of modern medical science and technology is the blurring of the line between life and death, something that was never an issue before modern medicine (Griniezakis, 2007; Levine, 2008). That was the case even before the most recent revelations in 2009 that many patients previously diagnosed as being in long-term persistent vegetative states actually remained conscious throughout their ordeal and that several patients considered
Few hospitals offered both the expertise and the necessary facilities. Location of the donor and the recipient also impacted availability. Human organs cool and degenerate quickly when removed from the donor. Transportation in the 50s, 60s, and 70s was in the early stages of rapid jet aircraft travel and was too slow for the transportation of organs. The donor needed to be in close proximity to the recipient which was
Conjunctivitis The term conjunctivitis refers to any inflammatory condition of the membrane that lines the eyelids and covers the exposed surface of the sclera, and is the most common cause of "red eye" or "pink eye" (Abbott pp). Most often the etiology can be determined by a careful history and an ocular examination, however, culture is sometimes necessary to establish the diagnosis or to guide therapy (Abbott pp). The most common
Our semester plans gives you unlimited, unrestricted access to our entire library of resources —writing tools, guides, example essays, tutorials, class notes, and more.
Get Started Now