Crawford AZ, Patel DV, McGhee CN Comparison and repeatability of keratometric and corneal power measurements obtained by Orbscan II, Pentacam, and Galilei corneal tomography systems. Am J Ophthalmol. 2013 Jul;156(1):53-60. doi: 10.1016/j.ajo.2013.01.029. Epub 2013 Mar 28.
Demir S, Sönmez B, Yeter V, Ortak H Comparison of normal and keratoconic corneas by Galilei Dual-Scheimpflug Analyzer. Cont Lens Anterior Eye. 2013 Oct;36(5):219-25. doi: 10.1016/j.clae.2013.04.001. Epub 2013 Apr 30.
Feizi S, Yaseri M, Kheiri B Predictive Ability of Galilei to Distinguish Subclinical Keratoconus and Keratoconus from Normal Corneas. J Ophthalmic Vis Res. 2016 Jan-Mar;11(1):8-16. doi: 10.4103/2008-322X.180707.
Güler E, Yagci R, Akyol M, Arslanyilmaz Z, Balci M, Hepsen IF Repeatability and reproducibility of Galilei measurements in normal keratoconic and postrefractive corneas. Cont Lens Anterior Eye. 2014 Oct;37(5):331-6. doi: 10.1016/j.clae.2014.04.004. Epub 2014 Jun 14.
Holladay JT Keratoconus detection using corneal topography. J Refract Surg. 2009 Oct;25(10 Suppl):S958-62. doi: 10.3928/1081597X-20090915-11.
Jahadi Hosseini HR, Katbab A, Khalili MR, Abtahi MB Comparison of corneal thickness measurements using Galilei, HR Pentacam, and ultrasound. Cornea. 2010 Oct;29(10):1091-5. doi: 10.1097/ICO.0b013e3181cf98e5.
Meyer JJ, Gokul A, Vellara HR, Prime Z, McGhee CN Repeatability and Agreement of Orbscan II, Pentacam HR, and Galilei Tomography Systems in Corneas With Keratoconus. Am J Ophthalmol. 2017 Mar;175:122-128. doi: 10.1016/j.ajo.2016.12.003. Epub 2016 Dec 18.
Park SH, Choi SK, Lee D, Jun EJ, Kim JH Corneal thickness measurement using Orbscan, Pentacam, Galilei, and ultrasound in normal and post-femtosecond laser in situ keratomileusis eyes. Cornea. 2012 Sep;31(9):978-82. doi: 10.1097/ICO.0b013e31823d03fc.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
