20 research outputs found
Biometry and Intraocular Lens Power Calculation by Combined Scheimpflug-Placido Disc versus Optical Interferometry Devices
Purpose: To compare the results of the current gold standard, laser interferometry, and keratometry by the IOL-Master, with a newly developed Galilei G6 using raytracing software Okulix for intraocular lens (IOL) power calculations.
Methods: For comparison of the IOL-power calculation of both devices, we analyzed the difference between the actual one-month postoperative subjective refraction and the theoretically calculated target refraction before cataract surgery. The IOL was selected according to the IOL Master recommendation aiming for emmetropia after surgery. We analyzed the differences of the measurements of the basic biometric data in 205 healthy eyes by each device.
Results: Our study included 205 healthy, unoperated eyes from 117 patients (61 women, 56 men) aged 20 to 75 years. Twenty-two eyes of cataract patients were also included in this retrospective study design. The mean difference between the prediction of the postoperative refraction and the refraction actually achieved was 0.03 D for the IOL Master and â0.23 D for the Galilei G6. The difference was not statistically significant (P = 0.059). The difference between the IOL power calculation of the IOL Master and the calculation of the G6 was not statistically significant (P = 0.064). The difference between the predicted refraction of the G6 and the refraction achieved after one month was also not statistically significant (P = 0.12) and neither was the difference between the predicted refraction of the IOL Master and the achieved refraction (P = 0.39). The mean axial length was calculated as 24.21 ± 0.80 mm using the IOL Master and 24.27 ± 0.82 mm using the Galilei G6 device. The mean value regarding anterior chamber depth (ACD) of the IOL master was 3.46 ± 0.23 mm and for the Galilei was G6 3.51 ± 0.25 mm. When comparing the white to white (WTW) values of the IOL master, it showed mean values of 12.32 ± 0.31 and Galilei showed mean values of G6 12.21 ± 0.28. All of these differences (between Galileo and IOL Master measurements) were statistically significant (P < 0.001).
Conclusion: Both the laser interferometry/keratometry performed by the IOL Master and the interferometry/raytracing biometry strategy performed by the Galilei G6 demonstrated equal results when executing the IOL power calculation before cataract surgery in eyes with no prior ocular surgery
Safety and Precision of Two Different Flap-morphologies Created During Low Energy Femtosecond Laser-assisted LASIK
Purpose: Currently, two major principles exist to create LASIK flaps: firstly, a strictly horizontal (2D) cut similar to the microkeratome-cut and secondly an angled cut with a âstep-likeâ edge (3D). The strictly horizontal (2D) cut method can be performed using apparatus such as the low-energy FEMTO LDV Z8 laser and its predecessors which are specific to this type. Alternatively, the low-energy FEMTO LDV Z8 laserâs 3D flap design creates an interlocking flap-interface surface which potentially contributes toward flap stability. In addition, the FEMTO LDV Z8 offers flap-position adjustments after docking (before flap-creation). The current study analyzed precision, safety, efficacy, as well as patient self-reported pain and comfort levels after applying two different types of LASIK flap morphologies which were created with a low-energy, high-frequency femtosecond (fs) laser device. Methods: A prospective, interventional, randomized, contralateral eye, single-center comparison study was conducted from November 2019 to March 2020 at the Hamburg vision clinic/ zentrumsehstĂ€rke, Hamburg, Germany. Eleven patients and 22 eyes received low-energy fs LASIK treatment for myopia or myopic astigmatism in both eyes. Before the treatment, the eyes were randomized (one eye was treated with the 2D, the other eye with the 3D method). Results: The mean central flap thickness one month after surgery was 110.7 ± 1.6 ÎŒm (2D) and 111.2 ± 1.7 ÎŒm (3D); P = 0.365 (2D vs 3D). Flap thickness measured at 13 different points resulted in no statistically significant differences between any of the measurement points within/between both groups; demonstrating good planarity of the flap was achieved using both methods. Despite not being statistically significant, the surgeons recognized an increase in the presence of an opaque bubble layer in the 3D flap eyes during surgery and some patients reported higher, yet not statistically significant, pain scores in the 3D flap eyes during the first hours after the treatment. Overall, safety- and efficacy indices were 1.03 and 1.03, respectively. Conclusion: In this prospective, randomized, contralateral eye study, the low-energy fs laser yielded predictable lamellar flap thicknesses and geometry at one-month followup. Based on these results, efficacy and safety of the corresponding laser application, that is, 2D vs 3D, are equivalen
Bilateral Crystalline Corneal Deposits as First Clinical Manifestation of Monoclonal Gammopathy: A Case Report
Aims: To report the clinical and diagnostic findings of a patient with bilateral corneal deposits caused by an underlying monoclonal gammopathy. Methods: Slit-lamp biomicroscopy, confocal microscopy and additional serological tests were performed on a 35-year-old man presenting with bilateral crystalline corneal deposits. Results: The patient was diagnosed as having monoclonal gammopathy based on elevated levels of serum immunoglobulin G. Confocal microscopy showed highly reflective (protein) deposits throughout the entire cornea, with the highest density in the epithelium and anterior stromal keratocytes. Conclusions: Monoclonal gammopathy, a potential sign of a life-threatening disease, can lead to dense, bilateral corneal deposits. As such changes can occur long before ocular or systemic discomforts appear, an early diagnosis is crucial. Ophthalmologists should be aware of corneal deposits as potential warning signs of monoclonal gammopathy
Corneal Biomechanical Changes after Crosslinking for Progressive Keratoconus with the Corneal Visualization Scheimpflug Technology
Purpose. To evaluate the effect of corneal crosslinking in progressive keratoconus by applying in vivo corneal visualization Scheimpflug technology. Design. Longitudinal retrospective study. Subjects and Controls. Seventeen eyes of patients treated with corneal crosslinking for progressive keratoconus. Methods. Corneal visualization Scheimpflug technology analyses (research software version 6.07r08) of subjects with progressive keratoconus before and 3 months after corneal crosslinking (CXL) were reviewed retrospectively. t-test (for normal distribution) and Wilcoxon matched-pairs test (if not normally distributed) were used to test for statistically significant differences between pre- and post-CXL analyses. Results. We demonstrated statistically significant differences for the intraocular pressure (median: +3âmmHg, P =0.004), the central corneal pachymetry (pachy; mean: â35â”m, P<0.001), the timespan between the air impulse release and the first applanation of the cornea (A1time; median: +0.12âms, P<0.05), and the timespan between the air impulse release and the second applanation of the cornea (A2time; median: â37âms, P<0.05). Conclusions. With the A1time and the A2time, we identified two parameters that demonstrated a statistically significant improvement of the biomechanical properties of the cornea after CXL. Despite the known initial decrease of the pachymetry after CXL, none of the analyzed parameters indicated a progression of the keratoconus
Laser in situ keratomileusis for astigmatismââ€â0.75 Diopter combined with low myopia: a retrospective data analysis
Exploring the Potential of ChatGPT-4 in Predicting Refractive Surgery Categorizations: Comparative Study
BackgroundRefractive surgery research aims to optimally precategorize patients by their suitability for various types of surgery. Recent advances have led to the development of artificial intelligenceâpowered algorithms, including machine learning approaches, to assess risks and enhance workflow. Large language models (LLMs) like ChatGPT-4 (OpenAI LP) have emerged as potential general artificial intelligence tools that can assist across various disciplines, possibly including refractive surgery decision-making. However, their actual capabilities in precategorizing refractive surgery patients based on real-world parameters remain unexplored.
ObjectiveThis exploratory study aimed to validate ChatGPT-4âs capabilities in precategorizing refractive surgery patients based on commonly used clinical parameters. The goal was to assess whether ChatGPT-4âs performance when categorizing batch inputs is comparable to those made by a refractive surgeon. A simple binary set of categories (patient suitable for laser refractive surgery or not) as well as a more detailed set were compared.
MethodsData from 100 consecutive patients from a refractive clinic were anonymized and analyzed. Parameters included age, sex, manifest refraction, visual acuity, and various corneal measurements and indices from Scheimpflug imaging. This study compared ChatGPT-4âs performance with a clinicianâs categorizations using Cohen Îș coefficient, a chi-square test, a confusion matrix, accuracy, precision, recall, F1-score, and receiver operating characteristic area under the curve.
ResultsA statistically significant noncoincidental accordance was found between ChatGPT-4 and the clinicianâs categorizations with a Cohen Îș coefficient of 0.399 for 6 categories (95% CI 0.256-0.537) and 0.610 for binary categorization (95% CI 0.372-0.792). The model showed temporal instability and response variability, however. The chi-square test on 6 categories indicated an association between the 2 ratersâ distributions (ÏÂČ5=94.7, P<.001). Here, the accuracy was 0.68, precision 0.75, recall 0.68, and F1-score 0.70. For 2 categories, the accuracy was 0.88, precision 0.88, recall 0.88, F1-score 0.88, and area under the curve 0.79.
ConclusionsThis study revealed that ChatGPT-4 exhibits potential as a precategorization tool in refractive surgery, showing promising agreement with clinician categorizations. However, its main limitations include, among others, dependency on solely one human rater, small sample size, the instability and variability of ChatGPTâs (OpenAI LP) output between iterations and nontransparency of the underlying models. The results encourage further exploration into the application of LLMs like ChatGPT-4 in health care, particularly in decision-making processes that require understanding vast clinical data. Future research should focus on defining the modelâs accuracy with prompt and vignette standardization, detecting confounding factors, and comparing to other versions of ChatGPT-4 and other LLMs to pave the way for larger-scale validation and real-world implementation
Pre- and postoperative angle kappa in MIOL patients after touch-up LASIK
Purpose To study the influence of angle kappa (Îș) on visual acuity after implantation of a multifocal intraocular lens (MIOL) and consecutive âtouch-upâ corneal refractive surgery with Laser-in-situ-Keratomileusis (LASIK). Methods This retrospective multicenter study included patients who underwent MIOL surgery and consecutive LASIK (= Bioptics) in the period from 2016 to 2020 at Care Vision Refractive Centers in Germany. Our study was approved by the local ethics committee at the University in Duesseldorf (approval date: 23.04.2021) and conducted according to the tenets of the Declaration of Helsinki and Good Clinical Practices Guidelines. The pre- and post-operative Îș of 548 eyes were measured using a Scheimpflug-based imaging system. Corrected distance visual acuity (CDVA) and the safety index (SI) were analyzed in relation with Îș. For a more detailed analysis, the cohort was divided into pre-operative hyperopic and myopic patients to show group-specific differences. Results There was a significant decrease (pConclusion A large Îș is not a significant risk factor for poor visual acuity. Therefore, it is not a suitable clinical predictor of postoperative outcomes after a Bioptic procedure
Pre- and postoperative angle kappa in MIOL patients after touch-up LASIK.
PurposeTo study the influence of angle kappa (Îș) on visual acuity after implantation of a multifocal intraocular lens (MIOL) and consecutive "touch-up" corneal refractive surgery with Laser-in-situ-Keratomileusis (LASIK).MethodsThis retrospective multicenter study included patients who underwent MIOL surgery and consecutive LASIK (= Bioptics) in the period from 2016 to 2020 at Care Vision Refractive Centers in Germany. Our study was approved by the local ethics committee at the University in Duesseldorf (approval date: 23.04.2021) and conducted according to the tenets of the Declaration of Helsinki and Good Clinical Practices Guidelines. The pre- and post-operative Îș of 548 eyes were measured using a Scheimpflug-based imaging system. Corrected distance visual acuity (CDVA) and the safety index (SI) were analyzed in relation with Îș. For a more detailed analysis, the cohort was divided into pre-operative hyperopic and myopic patients to show group-specific differences.ResultsThere was a significant decrease (pConclusionA large Îș is not a significant risk factor for poor visual acuity. Therefore, it is not a suitable clinical predictor of postoperative outcomes after a Bioptic procedure
Influence of the patientâs age on the safety, efficacy, and prediction accuracy of the microkeratome in laser-assisted in situ keratomileusis
Abstract The purpose of this retrospective pseudonymised data analysis was to determine whether the patientâs age has an influence on the safety, efficacy, and prediction accuracy of laser in situ keratomileusis (LASIK) treatment of myopic and hyperopic eyes. This study was performed at CARE Vision GmbH (DĂŒsseldorf, Germany) and included two patient cohorts: an older group with patientsâ>â55 years old and a younger group with patients 30â40 years old. Each patient had a single LASIK treatment. The safety, efficacy, and prediction accuracy of the refractive results were analysed. In total, 682 patients were analysed, with 341 patients in each patient group (one eye per patient). There were 570 myopic eyes and 112 hyperopic eyes. In myopic eyes, the efficacy was significantly influenced by the patientâs age but only in myopic eyes (myopic: pââ€â0.05; hyperopic: pâ=â0.085), while safety was not significantly influenced by the patientâs age in hyperopic or myopic eyes (pâ=â0.204). We found that LASIK treatment at an older age (>â55 years) resulted in almost the same safety outcomes as a LASIK treatment at a younger age (30â40 years) but with a lower efficacy; the efficacy correlated with the patientâs age. If the patient was hyperopic, their age did not influence safety or efficacy
Diffractive trifocal lens implantation with or without excimer laser enhancement: is a touch-up procedure a negative predictor for refractive and subjective outcome?
Purpose!#!To investigate the refractive results of a LASIK enhancement and its impact on treatment safety, efficacy, predictability and patient reported outcome in eyes after clear lens extraction and diffractive trifocal lens implantation.!##!Methods!#!A retrospective cohort multicentre study of Care Vision Refractive Centres in Germany compared two groups of patients. Group 1 consisted of eyes that had non-toric MIOL surgery only, whereas group 2 had a consecutive laser enhancement after 3Â months follow-up. Refractive and subjective results of the two groups were compared. Patient reported outcome measurements were assessed by using a 30-item questionnaire with four subscales. (Spectacle Dependence, Eye Comfort, Freedom and Looking/Feeling Well). Refractive results were reported following standard reporting in refractive surgery.!##!Results!#!139 eyes of 79 patients were included in which either MIOL surgery or MIOL surgery plus LASIK enhancement had been performed between January and December 2017. UDVA reached 0.1logMAR (0.8; 20/25) in 94% in group 2 and 85% in group 1. Compared to preoperative CDVA no change in Snellen lines of CDVA was shown in 89% in group 1 and in 93% in group 2. Spectacle dependence (Pâ=â0.41), eye comfort (Pâ=â0.15), freedom (Pâ=â0.48) and looking/feeling well (Pâ=â0.45) showed no statistically significant difference between both the groups.!##!Conclusions!#!In patients with residual ametropia after MIOL implantation, LASIK provides a reliable, safe and efficient way to achieve the desired refractive outcome and patient satisfaction. We recommend performing Laser enhancement at 3Â months after MIOL implantation (Bioptics) in trifocal MIOL patients that benefit from improvement of residual ametropia