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A Laser-induced Mouse Model of Chronic Ocular Hypertension to Characterize Visual Defects
Published on: August 14, 2013
Intraocular pressure and ocular rigidity after LASIK.
Sebastião Cronemberger1, Cláudia Savassi Guimarães, Nassim Calixto
1Department of Ophthalmology, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil. cronem@medicina.ufmg.br
Arquivos Brasileiros De Oftalmologia
|October 13, 2009
Summary
LASIK surgery lowers intraocular pressure (IOP) readings measured by Goldmann applanation tonometry but not Schiotz tonometry. Ocular rigidity also decreases after LASIK, with measurements stabilizing by six months post-surgery.
Area of Science:
- Ophthalmology
- Refractive Surgery
- Ocular Biomechanics
Background:
- Laser-Assisted In Situ Keratomileusis (LASIK) is a common refractive surgery.
- Accurate intraocular pressure (IOP) measurement is crucial for diagnosing and monitoring glaucoma.
- Ocular rigidity (E) influences IOP readings, and its changes after refractive surgery require investigation.
Purpose of the Study:
- To evaluate the impact of LASIK on intraocular pressure (IOP) and ocular rigidity (E).
- To assess IOP and E at multiple time points (1, 3, 6, 24 months) after LASIK.
- To compare IOP measurements obtained by Goldmann applanation tonometer (GAT) and Schiotz tonometer (ST) post-LASIK.
Main Methods:
- Prospective study involving 23 eyes undergoing LASIK.
- IOP measured using Goldmann applanation tonometer (GAT) and Schiotz tonometer (ST) with 5.5 and 10 gm weights.
- Ocular rigidity (E) assessed by differential tonometry using ST weights.
- Corneal indentation volume (Vc) and tonometric pressure (Pt) were also evaluated.
Main Results:
- LASIK resulted in lower average IOP (GAT) at 6 and 24 months compared to earlier time points.
- A statistically significant decrease in ocular rigidity (E) was observed at all postoperative follow-ups.
- Reduced central corneal thickness post-LASIK led to increased Vc and decreased Pt, influencing GAT and E measurements.
Conclusions:
- LASIK reduces IOP readings obtained by GAT, but not by ST (differential tonometry).
- LASIK diminishes ocular rigidity (E), with stabilization of Vc, Pt, and E parameters by 6 months.
- ST-based IOP evaluation is considered more accurate than GAT post-LASIK.
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