1.Preliminary evaluation of an algorithm to minimize the power error selection of an aspheric intraocular lens by optimizing the estimation of the corneal power and the effective lens position
Piero DAVIDP ; Camps VICENTEJ ; Ramn, MARAL ; Soto-Negro ROBERTO
International Eye Science 2016;16(6):1001-1008
?AIM: To evaluate the refractive predictability achieved with an aspheric intraocular lens ( IOL ) and to develop a preliminary optimized algorithm for the calculation of its power ( PIOL ) .?METHODS:This study included 65 eyes implanted with the aspheric IOL LENTIS L-313 ( Oculentis GmbH ) that were divided into 2 groups:12 eyes (8 patients) with PIOL≥23. 0 D (group A), and 53 eyes (35 patients) with PIOL<23. 0 D ( group B ). The refractive predictability was evaluated at 3mo postoperatively. An adjusted IOL power ( PIOLadj ) was calculated considering a variable refractive index for corneal power estimation, the refractive outcome obtained, and an adjusted effective lens position ( ELPadj ) according to age and anatomical factors.?RESULTS: Postoperative spherical equivalent ranged from -0. 75 to +0. 75 D and from -1. 38 to +0. 75 D in groups A and B, respectively. No statistically significant differences were found in groups A (P=0. 64) and B (P=0. 82 ) between PIOLadj and the IOL power implanted ( PIOLReal ) . The Bland and Altman analysis showed ranges of agreement between PIOLadj and PIOLReal of +1. 11 to -0. 96 D and +1. 14 to -1. 18 D in groups A and B, respectively. Clinically and statistically significant differences were found between PIOLadj and PIOL obtained with Hoffer Q and Holladay I formulas (P<0. 01).?CONCLUSION: The refractive predictability of cataract surgery with implantation of an aspheric IOL can be optimized using paraxial optics combined with linear algorithms to minimize the error associated to the estimation of corneal power and ELP.
2.Twelve-Month Volume Reduction Ratio Predicts Regrowth and Time to Regrowth in Thyroid Nodules Submitted to Laser Ablation: A 5-Year Follow-Up Retrospective Study
Roberto NEGRO ; Gabriele GRECO ; Maurilio DEANDREA ; Matteo RUCCO ; Pierpaolo TRIMBOLI
Korean Journal of Radiology 2020;21(6):764-772
Objective:
Laser ablation is a therapeutic modality used to reduce the volume of large benign thyroid nodules. Unsatisfactory reduction and regrowth are observed in some treated nodules. The aim of the study was to evaluate the long-term outcomes of laser treatment for solid nodules during a 5-year follow-up period, the regrowth rate, and the predictive risk factors of nodule regrowth.
Materials and Methods:
We retrospectively evaluated patients with benign, solid, cold thyroid nodules who underwent laser ablation and were followed-up for 5 years. According to the selection criteria, 104 patients were included (median baseline nodule volume, 12.5 mL [25.0–75.0%, 8–18 mL]; median energy delivered, 481.5 J/mL [25.0–75.0%, 370–620 J/mL]). Nodule volume, thyroid function test results, and ultrasound were evaluated at baseline and then annually after the procedure.
Results:
Of 104 patients, 31 patients (29.8%) had a 12-month volume reduction ratio (VRR) < 50.0% and 39 (37.5%) experienced nodule regrowth. Of these 39 patients, 17 (43.6%) underwent surgery and 14 (35.9%) underwent a second laser treatment. The rate of nodule regrowth was inversely related to the 12-month VRR, i.e., the lower the 12-month VRR, the higher the risk of regrowth (p < 0.001). The mean time for nodule regrowth was 33.5 ± 16.6 months. The 12-month VRR was directly related to time to regrowth, i.e., the lower the 12-month VRR, the shorter the time to regrowth (p < 0.001; R2 = 0.3516). Non-spongiform composition increased the risk of regrowth with an odds ratio of 4.3 (95% confidence interval [CI] 1.8–10.2; p < 0.001); 12-month VRR < 50.0% increased the risk of regrowth with an odds ratio of 11.7 (95% CI 4.2–32.2; p < 0.001).
Conclusion
The VRR of thyroid nodules subjected to similar amounts of laser energy varies widely and depends on the nodule composition; non-spongiform nodules are reduced to a lesser extent and regrow more frequently than spongiform nodules. A 12-month VRR < 50.0% is a predictive risk factor for regrowth and correlates with the time to regrowth.