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Abstract Keratoconus is a bilateral, progressive, non-inflammatory disease of the cornea which often leads to high myopia and astigmatism with an estimated prevalence of approximately 1 in 2000. In the general population, the incidence of keratoconus is estimated to be between 50 and 230 per 100,000. It seems to be a multifactorial disease with an unknown exact etiology which impairs the quantity and quality of vision secondary to thinning in and protrusion of the cornea. This results in an irregular astigmatism with or without myopia. Despite the fact that only one eye may be affected initially, keratoconus ultimately affects both eyes. The conservative management of keratoconus in early stages consists of spectacle correction or rigid contact lenses. In more advanced stages with severe corneal irregular astigmatism and stromal opacities, surgical treatment with deep lamellar keratoplasty and penetrating keratoplasty (PK) should be considered. ICRSs were designed with the goal of delaying or avoiding corneal grafts in keratoconus patients. It represents a prominent evolution in the management of keratoconus via flattening the central corneal curvature to achieve a refractive adjustment due to the removable and tissue saving nature of the technique. The high efficiency of Intacs in correcting keratoconic eyes has been reported by several authors. ICRS implantation in post-Lasik ectasia appears to be safe and effective in decreasing myopia, corneal steepness, and decentration of the corneal apex and offers potential improvement of UCVA and BSCVA in keratoconus patients. Summary 85 The high accuracy cuts to the corneal tissue demonstrated by femtosecond lasers in refractive surgery have generated new inquiry on their application into tunnel creation for precision ICRS insertion. The advantages of femtosecond channel creation over mechanical approaches are the following: a more uniform dissection is created; the results and ICRS placement are more consistent; and because it is minimally invasive, there is less patient discomfort and quicker recovery. Information about corneal curvature can be obtained with a variety of instruments that reflect the images of multiple concentric circles from the corneal surface. These devices allow analysis of corneal curvature in zones both central and peripheral to those measured by keratometry. In general, on steeper parts of the cornea, the reflected mires appear closer together and thinner and the axis of the central mire is shorter. Conversely, along the flat axis, the mires are farther apart and thicker, and the central mire is longer. The handheld Placido disk is a keratoscope with a flat target. Collimating keratoscopes use rings inside a column or a curve to maximize the area of the ocular surface that can reflect the target mires. Photokeratoscopy preserves the virtual image of concentric circles on film, and videokeratoscopy stores the images on video. We aimed in this study to evaluate the use of manual keratoscope intraoperative to improve the outcome of intracorneal ring segment implantation in patients with keratoconus. This was a prospective, consecutive, interventional comparative case study which included 40 patients with keratoconus. The participants were randomly divided into two subgroups according to Summary 86 the use of manual keraoscope intraoperative. group A: 20 patients were operated by non-aided implantation of ICRS without keratoscope while group B: 20 patients were operated with keratoscope assisted ICRS implantation. Results of the current study can be summarized in the following points: Regarding refraction sphere (pre-operative and post-operative), refraction cylinder sphere (pre-operative and post-operative), and BSCVA (pre-operative), there was a statistically non-significant difference between groups. While regarding BSCVA (Postoperative), there was a statistically a significant difference between groups (p=0.049). group B showed a higher BSCVA than group A (3.611 vs. 3.601). Twenty patients ranged in age between 17.0 – 35.0 years with a mean age of 26.75 ± 4.97 years for group A and 20 patients ranged in age between 16.0 – 40.0 years with a mean age 28.25 ± 7.08 years for group B. Regarding refraction SE (Pre-operative and Post-operative), there was a statistically non-significant difference between groups. While regarding SE (Pre-operative and Post-operative) within each group, there was a statistically significant difference (p<0.001, p= 0.012 in groups A and B respectively). Both Groups showed a decrease in SE. Regarding K1 (Post-operative) (p=0.004), K2 (Post-operative) (p=0.006), K max (Post-operative) (p=0.005), Max elevation (Front) (Post-operative) (p=0.001), there was a statistically significant difference between groups. Summary 87 Regarding K1 (Post-operative), K2 (Post-operative), K max (Postoperative), group B showed a lower K1 (42.40 vs 44.70), K2 (45 vs 48.50), and K max than group A (50.2 vs 55.10). While regarding Max elevation (Front) (Post-operative), group B showed a higher Max elevation (Front) than group A (28.10 ± 9.88 vs 18.53 ± 6.17).While Within each group, there was a statistically significant difference Post-operative (p<0.05). Regarding ACD (Pre-operative and Post-operative), there was a statistically non-significant difference between groups. While Within each group, there was a statistically a significant difference Post-operative (p=0.010 and p<0.001 in group A and B respectively). Regarding corneal volume (Pre-operative and Post-operative), that there was a statistically non-significant difference between groups. As well as within each group, there was a statistically nonsignificant difference. |