accuracy of iolmaster 700 total keratometry (tk)

Conditions: Myopia; Hyperopia; Cataract

Summary: this is a multicenter study to compare the accuracy of iol calculations in post-laser vision corrected eyes that are about to undergo or have undergone cataract surgery.

this is a multicenter study to compare the accuracy of iol calculations using 4 different iol calculation methods (haigis tk, ascrs calculator, barrett true k with classic k, and barrett true k tk) performed using the preoperative biometry data from post-laser vision correct eyes that are about to undergo or have undergone cataract surgery.

Eligibility criteria:
inclusion criteria: 1. adults, 18 years of age or older at the time of cataract surgery. 2. patient has had lvc and iol cataract surgery within 3 years or is scheduled to undergo iol cataract surgery performed for the treatment of visually significant cataracts. note: the only iols permitted for use in this study are monofocal (zcboo, li61ao, sn60wf, sa60wf, mx60e) and toric lenses (tecnis 2 zcu, zct, sn6atx, sa6atx, mx60et). 3. best corrected distance visual acuity (bcdva) potential of 20/30 or better (as measured by retinal acuity meter (ram) or potential acuity meter (pam). 4. patients who have a manifest refraction that is myopic or hyperopic after previous lvc. 5. patients that have biometric measurements (including axial length) for the iol cataract surgery that were performed preoperatively with the iolmaster700, including barrett true k /tk. 6. signed and received a copy of the signed written informed consent (pertain to the prospective subjects only). 7. for prospective patients, willingness and ability to comply with schedule for follow-up visits and postoperative evaluations. exclusion criteria: 1. patients with a history of any of the following: 1. corneal pathology - epithelial basement membrane dystrophy (embd), irregular astigmatism, decentered lasik/prk, radial keratotomy (rk), fuchs dystrophy 2. retinal pathology - visually significant epiretinal membrane (erm) with loss of foveal contour, large/ medium drusen, cystoid macular edema (cme), history of retinal detachment 3. optic neuropathy 4. advanced glaucoma 5. amblyopia 6. strabismus 7. relative afferent pupillary defect (rapd) indicating an optic neuropathy. 2. patients with a previous history of small incision lenticule extraction (smile) surgery and/or glaucoma filtering procedure (defined as tubes or trabeculectomy) other than photorefractive keratectomy (prk) or lasik. 3. patient who had to undergo a-scan measurement to retrieve axial length (al) values. 4. patient has had lvc and iol cataract surgery within 3 years or is scheduled to undergo iol cataract surgery performed for the treatment of visually significant cataracts with the presence or intention of implanting a multifocal, extended depth of focus, accommodating and light adjustable lens (such as, but not limited to, tfat / tfnt; dat / dft; icb00/dib/diu/dat; zxt; dfw; sn6ad1; at-50; rxsight). 5. patients in whom the study eye experiences any intraoperative surgical complications or complex cataract surgeries (vitrectomy, corneal suturing). 6. patients with previous lvc where one eye was treated for myopia and the other eye was treated for hyperopia. 7. patient is participating in another study.

Keywords: laser vision correction cataract surgery