ABSTRACT
Optical aberrations lead to defects in image-forming, the image obtained being imperfect and thereby decreasing the quality of vision. When an optic system is not perfect, as happens with the eye, the rays of light that pass through the system produce optical aberrations. The purpose of this review is to describe optical aberrations and their impact on vision and how refractive surgery outcomes are influenced by them. The main optical aberrations of the eye are as follows: spherical aberration, chromatic aberration, oblique astigmatism and high order aberrations. When the patient undergoes various types of surgeries (cataract surgery, corneal refractive surgery) the properties of the eye change and the eye doctor must take into account the correction of optical aberrations to improve vision quality. Abbreviations: LASIK (laser in situ keratomileusis), PRK (photorefractive keratectomy), UDVA (uncorrected distance visual acuity), SA (spherical aberrations), HOA (higher-order aberrations), RMS (root mean square).
ABSTRACT
UNLABELLED: Glaucoma is an important eye disease that, left untreated, causes irreversible blindness by affecting optic nerve threads. Decreasing intraocular pressure and maintaining it at a low level throughout the day is one of the objectives of antiglaucoma therapy. METHODS: This is a prospective study conducted on a sample of 80 patients who presented at "Emergency Eye Hospital" Bucharest between 1st of December 2013 30th of July 2014. Patients were divided into two groups: 40 patients with glaucoma and 40 patients without glaucoma (control group). THE OBJECTIVE OF THE STUDY: To determine changes in intraocular pressure that may occur depending on body posture and the correlations between changes in intraocular pressure and glaucoma, obesity, hypertension. These IOP changes may be important in the progression of glaucoma regarding that one third of our time is spent on supine position during night. RESULTS AND CONCLUZIONS: IOP varies from sitting down to supine position. IOP increases in supine in most patients (with or without glaucoma) with an average of 1.25 mmHg. The increase among patients with glaucoma is higher (1.67 mmHg) compared to those without glaucoma (0.82 mmHg). In patients with hypertension and glaucoma, IOP increased with 2.62 mmHg. In patients with hypertension and obesity IOP increased with 2.5 mmHg.
