ABSTRACT
PURPOSE: To characterize the surgically-induced-astigmatism (SIA) associated with spherical LASIK. METHODS: Refractive outcomes in 70 eyes that underwent primary myopic LASIK with purely spherical ablation were analyzed. The Summit Apex Plus excimer laser was used. The Bausch & Lomb Hansatome with the 180-microm plate was used to produce superiorly hinged flaps. The relationship between refractive astigmatism and corneal topographic astigmatism was analyzed using linear regression and vector analysis. RESULTS: There was a statistically significant negative correlation (slope = -0.21) between refractive surgically-induced astigmatism and preoperative topographic cylinder. A 0.24-D with-the-rule shift was also found. Surgically-induced astigmatism was not correlated with the magnitude of laser ablation. CONCLUSION: The lamellar keratotomy portion of LASIK reduces pre-existing corneal astigmatism and produces a relative steepening of the hinge meridian.
Subject(s)
Astigmatism/etiology , Cornea/pathology , Keratomileusis, Laser In Situ/adverse effects , Myopia/surgery , Adult , Astigmatism/diagnosis , Cornea/surgery , Diagnostic Techniques, Ophthalmological , Female , Humans , Male , Middle AgedABSTRACT
We report a case of tuberculum sellae meningioma with optic tract edema. Contrary to a prior report on this topic, edema along the optic tract is not only seen in craniopharyngiomas but may be seen (although rarely) in other common parasellar tumors, as in our case of a tuberculum sellae meningioma. The pathogenesis of this edema in meningioma is controversial.
