Accuracy of 8 intraocular lens calculation formulas in relation to anterior chamber depth in patients with normal axial lengths

2018 ◽  
Vol 44 (3) ◽  
pp. 362-368 ◽  
Author(s):  
Sabite Emine Gökce ◽  
Ildamaris Montes De Oca ◽  
David L. Cooke ◽  
Li Wang ◽  
Douglas D. Koch ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Intraocular Lens ◽  
Anterior Chamber Depth ◽  
Intraocular Lens Calculation

scholarly journals Effect of anterior chamber depth on the choice of intraocular lens calculation formula in patients with normal axial length

2014 ◽  
Vol 21 (4) ◽  
pp. 307 ◽  
Author(s):  
Hassan Hashemi ◽  
Mehdi Khabazkhoob ◽  
Farhad Rezvan ◽  
Akbar Fotouhi ◽  
Soheila Asgari ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Intraocular Lens ◽  
Axial Length ◽  
Anterior Chamber Depth ◽  
Calculation Formula ◽  
Intraocular Lens Calculation

scholarly journals Progress in Modern Cataract Surgery – New Steps and Algorithms for Precise Measuring and Intraocular-lens Calculations

2017 ◽  
Vol 11 (02) ◽  
pp. 95
Author(s):  
Fritz H Hengerer ◽  
Gerd U Auffarth ◽  
Ina Conrad-Hengerer ◽  
◽  
◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Anterior Chamber ◽  
Intraocular Lens ◽  
Axial Length ◽  
Refractive Surgery ◽  
Anterior Chamber Depth ◽  
Corneal Surface ◽  
Intraocular Lens Calculations ◽  
Target Refraction ◽  
Intraocular Lens Calculation

In standard cataract surgery, one of the major goals is to reach target refraction. Based on keratometry measurements, axial length and anterior chamber depth, most of the intraocular lens calculation formulae are suitable to achieve this aim. Further evaluation of corneal refractive parameters like anterior and posterior corneal surface by Scheimpflug devices led to a significant enhancement of precision in astigmatic and post-refractive surgery cases.

Lenstar® LS 900 vs Pentacam®-AXL: Comparative study of ocular biometric measurements and intraocular lens power calculation

2018 ◽  
Vol 28 (6) ◽  
pp. 645-651 ◽  
Author(s):  
Joana Maria Mendes Pereira ◽  
Arminda Neves ◽  
Pedro Alfaiate ◽  
Mónica Santos ◽  
Henrique Aragão ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Intraocular Lens ◽  
Axial Length ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Anterior Chamber Depth ◽  
T Test ◽  
Biometric Measurements ◽  
Paired T Test ◽  
Intraocular Lens Calculation

Purpose: Comparison of biometric measurements and calculation of intraocular lens with a new biometer (Pentacam®-AXL, Oculus, Germany) and a reference biometer (Lenstar LS 900®, Haag-Streit AG, Switzerland), in order to assess the agreement between these two devices. Setting: Centro Hospitalar de Leiria, Portugal Materials and methods: Prospective, institutional study, in which measurements of axial length, anterior chamber depth from the corneal epithelium and endothelium to the anterior surface of the lens (anterior chamber depth ext and anterior chamber depth int), central corneal thickness and keratometry readings of the flattest and steepest meridians (K1 and K2) were obtained with the two systems. Intraocular lens calculation was also performed, using the Haigis, SRK/T and HofferQ formulas. Results: The study sample included 136 eyes of 79 patients. Of these, 42 were women and 37 were men. Statistically significant differences were found (p < 0.05, paired T test) in K1, K2 and central corneal thickness between the 2 biometers. Intraocular lens calculation with the Lenstar® and the Pentacam® with Haigis, SRK/T and HofferQ formulas showed statistically significant differences (p < 0.05 Paired T test). Conclusion: Axial length measurements obtained with the Pentacam® and Lenstar® appear to be interchangeable, while measurements of anterior chamber depth, K1 and K2, and central corneal thickness do not appear to be interchangeable between different devices. Statistically significant differences were found in the calculation of intraocular lenses in all formulas used.

scholarly journals Accuracy of intraocular lens calculation formulas in cataract patients with steep corneal curvature

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0241630
Author(s):  
Chenguang Zhang ◽  
Guangzheng Dai ◽  
Emmanuel Eric Pazo ◽  
Ling Xu ◽  
Xianwei Wu ◽  
...  
Keyword(s):  
Anterior Chamber ◽  
Intraocular Lens ◽  
Refractive Error ◽  
Anterior Chamber Depth ◽  
Covariance Analysis ◽  
Corneal Curvature ◽  
Refractive Power ◽  
Iol Power ◽  
Cataract Patients ◽  
Intraocular Lens Calculation

Objective To compare the accuracy of five kinds of intraocular lens calculation formulas (SRK/T, Haigis, Hoffer Q, Holladay and Barrett Universal Ⅱ) in cataract patients with steep curvature cornea ≥ 46.0 diopters. Methods This is a retrospective study of cataract phacoemulsification combined with intraocular lens implantation in patients with steep curvature cornea (corneal curvature ≥ 46D). The refractive prediction errors of IOL power calculation formulas (SRK/T, Haigis, Holladay, Hoffer Q, and Barrett Universal II) using User Group for Laser Interference Biometry (ULIB) constants were evaluated and compared. Objective refraction results were assessed at one month postoperatively. According to axial length (AL), all patients were divided into three groups: short AL group (<22mm), normal AL group (>22 to ≤24.5mm) and long AL group (>24.5mm). Calculate the refractive error and absolute refractive error (AE) between the actual postoperative refractive power and the predicted postoperative refractive power. The covariance analysis was used for the comparison of five formulas in each group. The correlation between the absolute refractive error and AL from every formula were analyzed by Pearson correlation test, respectively. Result Total 112 eyes of 83 cataract patients with steep curvature cornea were collected. The anterior chamber depth (ACD) was a covariate in the short AL group in the covariance analysis of absolute refractive error (P<0.001). The SRK/T and Holladay formula had the lowest mean absolute error (MAE) (0.47D), there were statistically significant differences in MAE between the five formulas for short AL group (P = 0.024). The anterior chamber depth had no significant correlation in the five calculation formulas in the normal AL group and long AL group (P = 0.521, P = 0.609 respectively). In the normal AL group, there was no significant difference in MAE between the five calculation formulas (P = 0.609). In the long AL group, Barrett Universal II formula had the lowest MAE (0.35), and there were statistically significant differences in MAE between the five formulas (P = 0.012). Over the entire AL range, the Barrett Universal II formula had the lowest MAE and the highest percentage of eyes within ± 0.50 D, ± 1.00 D, and ± 1.50 D (69.6%, 93.8%, and 98.2% respectively). Conclusion Compared to SRK/T, Haigis, Hoffer Q, and Holladay, Barrett Universal Ⅱ formula is more accurate in predicting the IOL power in the cataract patients with steep curvature cornea ≥ 46.0 diopters.

scholarly journals A Case of Repeating Transient Increase in Intraocular Pressure by Instability of an Intraocular Lens Implanted in the Capsular Bag

2020 ◽  
Vol 11 (1) ◽  
pp. 60-67
Author(s):  
Yukihisa  Takada ◽  
Takayoshi Sumioka ◽  
Nobuyuki Ishikawa ◽  
Shingo Yasuda ◽  
Ryoko Komori ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Anterior Chamber ◽  
Intraocular Lens ◽  
Anterior Chamber Depth ◽  
Acute Angle ◽  
University Hospital ◽  
Angle Closure ◽  
Light Reaction ◽  
Narrow Angle ◽  
Medical University

We observed repeated episodes of rapid increases in intraocular pressure (IOP) considered to be caused by an in-the-bag intraocular lens (IOL) instability in a patient with an implanted IOL. As acute glaucoma attack-like increase in IOP was noted in the left eye on November 8, she was admitted to Wakayama Medical University Hospital. The findings at the first examination included an IOP of 62 mm Hg, instability of a PMMA one-piece IOL, shallow anterior chamber, narrow angle, moderate mydriasis, and loss of pupillary light reaction in the left avitreous eye. On November 15, a 6-mm Hg increase in IOP was observed during 60-min dark room prone provocative testing. After the first examination, the patient perceived pain and reduced visual acuity of the left eye and emergently consulted our hospital twice. Despite miosis, normalization of the anterior chamber depth and IOP with widening of the angle were achieved by resting in the supine position. These episodes were thought to be caused by instability and anterior shift of the IOL. On January 17, 2018, suture fixation of the in-the-bag IOL was performed. The IOL was fixed by transscleral suturing of the bilateral supporting parts to the sclera. Recurrence of sudden ophthalmalgia, instability of the in-the-bag IOL, and an increase in IOP have not been observed for 1 year after surgical treatment. Instability of an in-the-bag IOL caused repeated acute angle-closure glaucoma-like attacks. The situation was well treated by suturing and fixing the haptics of IOL to the sclera.

Sign in / Sign up

Export Citation Format

Share Document