Disease relevance of Astigmatism

• Clinically, each patient had essentially normal fundi, mildly reduced corrected visual acuity, and slight myopia or hyperopia with astigmatism [1].
• The prevalence of myopia, astigmatism, and anisometropia significantly increased with age (all P<0.01) [2].
• Significant amblyogenic conditions, such as hyperopic anisometropias of more than 1.0 diopter (D), high ametropias, or astigmatism and strabismus cases of 2 degrees to 3 degrees or more are detectable [3].
• An array of procedures to correct myopia, hyperopia, astigmatism, and presbyopia have been introduced over the past 25 years with varying degrees of success [4].
• CONCLUSIONS: Implantation of a single Intacs segment inferiorly appeared to improve progressive myopia and regular and irregular astigmatism in eyes with corneal ectasia after LASIK [5].

High impact information on Astigmatism

• The progression rate of astigmatism was affected by the ethnicity, presence of myopia, axis, and subtype of astigmatism [6].
• Most aberration terms were similar, averaged across the 70 patients, before and after surgery (spherical aberration: pre, 0.32 +/- 0.12 microm, and post, 0.34 +/- 0.19 microm; astigmatism: pre, 0.9 +/- 0.8 D, and post, 1.1 +/- 1.0 D; coma: pre, 0.27 +/- 0.18 microm, and post, 0.32 +/- 0.33 microm) [7].
• The prevalence of WTR and ATR astigmatism significantly decreased (P < 0.001) and increased (P = 0.006) with age, respectively [8].
• The age and gender standardized prevalences of myopia (< -0.5 D), emmetropia, hyperopia (> +0.5 D), astigmatism (< -0.5 D of cylinder) and anisometropia (>1.0 D difference between eyes) were 17.2%, 49.9%, 32.9%, 40.9%, and 10.7%, respectively [9].
• In this Letter we provide what is believed to be the first experimental evidence of suppression of the number of filaments for high-intensity laser pulses propagating in air by beam astigmatism [10].

Chemical compound and disease context of Astigmatism

• CONCLUSIONS: PARK with the Summit Apex Plus excimer laser is effective at reducing compound myopic astigmatism [11].
• Correction of irregular astigmatism with excimer laser assisted by sodium hyaluronate [12].
• Myopia was common (14 of 28; 50%) in those exposed to valproate monotherapy and there were high frequencies of strabismus (20%), astigmatism (24%), and anisometropia (11%) in the group as a whole [13].
• RESULTS: Regular astigmatism in the PMMA group was greater than in the silicone and acrylic groups [14].
• A controlled study compared the effects of a topical steroid (1% prednisolone acetate) and a topical nonsteroidal anti-inflammatory agent (0.03% flurbiprofen) on postoperative changes in corneal astigmatism in a series of patients having phacoemulsification and posterior chamber lens implantation through a 6.5 mm scleral pocket incision [15].

Biological context of Astigmatism

• SETTING: Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. METHODS: Eighteen eyes had implantation of an iris-supported toric phakic IOL to correct myopia with astigmatism [16].
• Changes in intraocular pressure after laser in situ keratomileusis for myopia, hyperopia, and astigmatism [17].
• CONCLUSIONS: Interesting speculations are offered about the effects of myopia, astigmatism, presbyopia, and altered color vision on the works of such well-known artists as Monet, Holbein, Whistler, Gainsborough, and many others [18].
• An investigation has revealed a relationship between changes in astigmatism and an observable triad consisting of eye scan, head movement, and head posture [19].
• All patients showed oculopathy, mainly neuro-ophthalmological impairments such as: 1. optic neuropathy, 2. degeneration of the retina, 3. defective vertical smooth pursuit, 4. myopia; spasm or paresis of accommodation with or without corneal astigmatism "with the rule" and mild general neurological impairments [20].

Anatomical context of Astigmatism

• MAIN OUTCOME MEASURES: Preoperative and postoperative best spectacle-corrected visual acuity (BSCVA), manifest refraction astigmatism, TMS-1 topography, ultrasonic pachymetry, Orbscan topography, and endothelial cell density were evaluated [21].
• Clinical examination revealed blue sclera, limbus-to-limbus corneal thinning, myopia, and astigmatism [22].
• CONCLUSION: Scanning slit laser treatment after precise removal of the epithelium with a rotary scrubber, prescrub, and postlaser cooling allowed rapid, accurate correction of myopia and astigmatism [23].
• Repeatability of the TMS-1 on normal corneas was found to be: (a) observer related, and (b) astigmatism related [24].
• Ocular signs are prevalent, including small palpebral fissure, microcornea, strabismus, myopia, astigmatism, and optic nerve hypoplasia [25].

Gene context of Astigmatism

• PARTICIPANTS: Forty-eight eyes of 14 men and 34 women (age range, 26-54; mean, 39.2 years) who underwent bilateral LASIK for myopia or myopic astigmatism [26].
• Lower field myopia is not an artifact of oblique astigmatism, nor of an aberration symmetrical about the optical axis [27].
• With-the-rule (WTR) astigmatism of at least 0.25 D was the most frequent form (45%) followed by against-the-rule (ATR; 40%) and oblique (15%) [28].
• The PVP ranged from 84% when a diagnosis of strabismus was suggested by the photoscreen reading to 41% for astigmatism [29].
• OBJECTIVE: To study the efficacy of photoastigmatic refractive keratectomy (PARK) by the MEL 60 (Aesculap-Meditec, Jana, Germany) scanning excimer laser for the treatment of myopic astigmatism, with follow-up of 18 months [30].

Analytical, diagnostic and therapeutic context of Astigmatism

• Laser in situ keratomileusis for myopia up to -11 diopters with up to -5 diopters of astigmatism with the summit autonomous LADARVision excimer laser system [31].
• PURPOSE: The purpose of the study is to evaluate the induced astigmatism after spherical photorefractive keratectomy on the Summit Omnimed (Summit Instruments, Waltham, MA) and the Nidek EC-5000 (Nidek Co. Ltd, Aichi, Japan) excimer lasers [32].
• LASIK is more effective in treating myopia than astigmatism after penetrating keratoplasty [33].
• Corneal sensitivity was tested in 76 eyes of 40 patients who underwent radial keratotomy for the correction of myopia, and radial keratotomy plus transverse incisions for the correction of myopia and astigmatism [34].
• Treatment of myopia and myopic astigmatism by customized laser in situ keratomileusis based on corneal topography [35].

References