scholarly journals Biometric changes after vitrectomy with silicone oil tamponade

2021 ◽  
Vol 2 (2) ◽  
pp. 56-62
Author(s):  
Simin Hosseini ◽  
Amir Faramarzi ◽  
Siamak Moradian ◽  
Mehdi Yaseri

Background: The Lenstar LS 900 (Haag-Streit AG, Koeniz, Switzerland) is an optical biometer, and its measurements are highly repeatable and precise in cataractous eyes. This study investigated changes in biometric parameters, including axial length (AL), anterior chamber depth (ACD), lens thickness (LT), vitreous cavity depth (VD), and central corneal thickness (CCT) before and after three-port 23-Gauge pars plana vitrectomy with silicone oil tamponade. Methods: This was a prospective follow-up study. Patients who were scheduled for surgery underwent a detailed slit-lamp examination and objective cycloplegic refraction preoperatively. In eligible cases, the Lenstar LS 900 was used to measure biometric parameters. At the 1-month postoperative follow-up, we repeated the same assessments for the silicone oil (SO)-filled eyes. Data were analyzed to assess the significance of changes and to test the possible correlation of values between the two time points. Results: Twenty-three patients with a mean ± SD age of 60 ± 12 years completed the study. Postoperatively, we found a significant increase in AL and a decrease in ACD and CCT (all P < 0.05), with no significant changes in LT and VD. A significant correlation was found for ACD, CCT, and cylinder values between the two time points (all P < 0.05). Postoperatively, the spherical and cylindrical components of refraction demonstrated a hyperopic shift, but did not change statistically significantly. Conclusions: The Lenstar LS 900 underestimated the ACD and overestimated the AL in SO-filled eyes when comparing pre- and postoperative values, in phakic as well as pseudophakic eyes. In planning for cataract surgery in this group of patients, it is more reasonable to calculate IOL power based on the biometric data of the fellow eye, although this may not eliminate possible errors. Further studies with a larger sample size, longer follow-up, and robust study design are necessary to confirm our preliminary results.

2020 ◽  
Author(s):  
Seyed Javad Hashemian ◽  
Acieh Es'haghi ◽  
Hossein Aghaei ◽  
Leila Ghiasian ◽  
Mohammad Ebrahim Jafari ◽  
...  

Abstract BACKGROUND: To assess long-term Visual and refractive stability and ocular biometric changes in low to moderate myopic subjects treated by customized LASEK. METHODS: Seventy eyes of 35 patients were treated by customized LASEK for correction of less than 6 diopter myopia in this cohort study. Uncorrected visual acuities (UCVA) and distance corrected visual acuities (DCVA), keratometry values and ocular biometric data by Lenstar LS900 including anterior chamber depth (ACD), aqueous depth, central corneal thickness(CCT),lens thickness(LT) and axial length(AL) were evaluated pre and 8 years postoperatively. RESULTS: Mean pre-operative spherical equivalent was -3.99 ±1.38 diopter (D) that improved to 0.01 ±0.27 D and -0.10 ±0.31 D, 6 months and 8 years postoperative respectively. Mean pachymetry, flat, steep and mean keratometry values increased significantly from 6 months to 8 years postoperative. Although, these changes had no significant effect on visual outcomes and subjective refraction. ACD decreased and LT increased significantly over 8 years follow-up in comparison with preoperative values. The change in AL was not significant at 8 years follow up.CONCLUSIONS: The long-term visual and refractive outcomes of customized LASEK in correction of low to moderate myopia were stable and predictable, although changes in ocular biometric parameters have occurred.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Junjie Wang ◽  
Bernardo T. Lopes ◽  
Hechen Li ◽  
Riccardo Vinciguerra ◽  
Si Cao ◽  
...  

AbstractBackgroundCorneal refractive surgery has become reliable for correcting refractive errors, but it can induce unintended ocular changes that alter refractive outcomes. This study is to evaluate the unintended changes in ocular biometric parameters over a 6-month follow-up period after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE).Methods156 consecutive myopic patients scheduled for FS-LASIK and SMILE were included in this study. Central corneal thickness (CCT), mean curvature of the corneal posterior surface (Kpm), internal anterior chamber depth (IACD) and the length from corneal endothelium to retina (ER) were evaluated before and after surgery over a 6-month period.ResultsBoth the FS-LASIK and SMILE groups (closely matched at the pre-surgery stage) experienced flatter Kpm, shallower IACD and decreased ER 1 week post-surgery (P < 0.01), and these changes were larger in FS-LASIK than in SMILE group. During the 1 week to 6 months follow up period, Kpm, IACD and ER remained stable unlike CCT which increased significantly (P < 0.05), more in the FS-LASIK group.ConclusionsDuring the follow up, the posterior corneal surface became flatter and shifted posteriorly, the anterior chamber depth and the length from the corneal endothelium to retina decreased significantly compared with the pre-surgery stage. These unintended changes in ocular biometric parameters were greater in patients undergoing FS-LASIK than SMILE. The changes present clear challenges for IOL power calculations and should be considered to avoid affecting the outcome of cataract surgery.


2019 ◽  
Vol 1 (2) ◽  
pp. 114-125
Author(s):  
Raja nor farahiyah Raja othman

Introduction: Pars plana vitrectomy (PPV) without endotamponade should not induce significant change to the refractive status of the eye. However, several studies have reported minor refractive changes after plain vitrectomy. Purpose: To compare the changes in refraction following PPV and to examine the biometry parameters that may affect the refractive change.Materials and methods: In this prospective cohort study, patients who were listed for 23-gauge 3-port PPV without buckling or silicone oil tamponade were enrolled between December 2015 and September 2017. Autorefraction, keratometry, anterior chamber depth (ACD), and axial length (AL) were measured preoperatively and three months postoperatively.Results: This study involved 41 eyes from 38 patients. The mean spherical equivalent (SE) before PPV was -1.08 dioptres (D), (standard deviation (SD) 2.18), which changed to a mean of -1.88 D (SD 2.20) postoperatively. The mean SE change was -0.80 D (SD 1.61, 95% confidence interval (CI) -1.31 to 0.30 D, P = 0.003). The median astigmatism before PPV was 0.69 D (Interquartile range (IQR) 0.69 D) reduced to 0.66 D (IQR 0.60 D) after PPV (P = 0.882). Median ACD preoperatively was 3.55 mm (IQR 0.76 mm) and reduced postoperatively to 3.44 mm (IQR 0.67 mm), (P = 0.028). The median AL was 23.36 mm (IQR 1.42 mm) and 23.48 mm (IQR 1.56 mm) before and after PPV, respectively, (P = 0.029). No significant SE change was found between phakic and pseudophakic groups (P = 0.155).Conclusion: Patients experience myopic shift post plain PPV, possibly due to the reduction of ACD. The ACD tended to be shorter in the pseudophakic group, suggesting that the myopic shift in the phakic group may be a result of the development of nuclear sclerosis cataract.


2019 ◽  
Author(s):  
Noah C Simon ◽  
Asim V. Farooq ◽  
Michael H. Zhang ◽  
Kamran M. Riaz

Abstract Background/Aims To examine the effect of pharmacologic dilation on biometric parameters measured by the Lenstar LS 900, and whether these changes affect the power of the calculated intraocular lens (IOL) using multivariable formulas in an undilated versus pharmacologically dilated state. Methods Prospective study of 98 phakic eyes from 53 patients. Axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), and keratometry (K) readings were measured. The first set of measurements was taken prior to dilation. After dilation (pupil diameter ≥6.0mm), a second set of measurements was taken. The Barrett, Olsen, Hill-RBF, Haigis, SRK/T, and Holladay I formulas were used to calculate IOL power before and after dilation. Two calculation methods were used: Method A used a commonly available IOL targeted to achieve the lowest myopic spheroequivalent residual refraction (LMP); Method B calculated ideal IOL power for emmetropia (IPE). Results Statistically significant increases were seen in CCT (p<0.01), ACD (p<0.01), and AL (p<0.01) whereas a statistically significant decrease was seen in LT (p<0.01) post dilation. Using Method A, the percentage of eyes which would have received an IOL with 0.5 D or 1.0 D of higher power, if post-dilation measurements were used, were 25.5%, 30.6%, 20.4% and 23.5% for Barrett, Olsen, Hill-RBF and Haigis, respectively. Using Method B, only Haigis and Olsen had a statistically significant increase in ideal IOL power. Conclusions Pharmacologic dilation can be associated with an increase in non-custom IOL dioptric power when using multivariable formulas, which may lead to a myopic surprise.


2021 ◽  
Vol 14 (3) ◽  
pp. 456-460
Author(s):  
Ling Bai ◽  
◽  
Yi-Dan He ◽  
Shu Zhang ◽  
Feng Wang ◽  
...  

AIM: To evaluate the effect of intracameral injection of conbercept for the treatment of advanced neovascular glaucoma (NVG) after vitrectomy with silicone oil tamponade. METHODS: Conbercept 0.5 mg/0.05 mL was injected into the anterior chamber of 5 eyes, which had developed advanced NVG after vitrectomy with silicone oil tamponade. Then, trabeculectomy with mitomycin C and pan-retinal photocoagulation (PRP) or extra-PRP were conducted within 2d. The follow-up time was 6mo. Best-corrected visual acuity (BCVA), intraocular pressure (IOP), neovascularization of iris (NVI) were recorded before and after treatment. RESULTS: Within 2d after injection, IOP control, and NVI regression were optimal for trabeculectomy. Hyphema occurred in one eye in the process of injection. But none of them present hyphema after trabeculectomy. At the end of follow-up time, all eyes had improved BCVA, well-controlled IOP, and completely regressed NVI. CONCLUSION: Intracameral injection of conbercept is safe and effective in the treatment of patients with advanced NVG after vitrectomy with silicone oil tamponade. Within 2d after injection is the optimal time window for trabeculectomy, which can maximally reduce the risk of perioperative hyphema.


2019 ◽  
Vol 2019 ◽  
pp. 1-5
Author(s):  
Jia Wang ◽  
Zhiwei Li ◽  
Huankai Zhang ◽  
Ning Gao ◽  
Guoying Mu

Purpose. To analyze the keratectasia area (KEA) shown in corneal topography before and after corneal cross-linking (CXL) in patients with progressive keratoconus (KC) and figure out whether KEA is appropriate for evaluating the effect of CXL. Methods. A retrospective analysis was conducted in 34 eyes from 24 progressive KC patients who have underwent CXL from 2015 to 2017. Area with K-value more than 47D shown in the corneal topography was marked and identified as KEA. Keratometry (K1, K2, and Kmax), KEA, thinnest corneal thickness (TCT), and endothelial cell density (ECD) were evaluated preoperatively or at months 3, 6, and 12 postoperatively. The changes of KEA before and after operation were evaluated. The relation of KEA and other parameters, including Kmax and TCT, was analyzed. Results. Linear regression model revealed the KEA, Kmax, K1, and K2 decreased after CXL in model y = 0.9622 -0.02408 x (P<0.05), y = 0.9982 -0.003469 x(P<0.05), y = 0.9977 + -0.001347 x(P<0.05), y = 0.9992 + -0.001779 x(P<0.05) (y represents KEA, Kmax, K1, or K2; x represents time (month)). The KEA is significantly decreased in early stage (before month 3) (P<0.05); however, the Kmax, K1, and K2 have no significant decrease in early stage (P= 0.09, 0.19, 0.32). Conclusions. The KEA is more sensitive than K-value in describing the morphological changes of cornea after CXL, especially in early stage after treatment.


2018 ◽  
Vol 2 (5) ◽  
pp. 297-301 ◽  
Author(s):  
Wajiha J. Kheir ◽  
Carl-Joe Mehanna ◽  
Mona Koaik ◽  
Ziad Bashshur

Purpose: Assess changes on spectral domain optical coherence tomography (OCT) before, during, and after removal of silicone oil (SO). Methods: Retrospective series of patients who underwent SO tamponade for macula-on rhegmatogenous retinal detachment. OCT scans of the affected eye were taken before, during, and 3 months after SO tamponade. Qualitative assessment of foveal contour and quantitative comparison of OCT parameters (central macular, cube, ganglion cell layer [GCL], and outer retinal thicknesses) were done between 3 time points. Results: Ten eyes of 9 patients were included. Flattening of the foveal contour during SO tamponade was completely reversed after SO removal. Average cube and GCL thicknesses decreased with SO tamponade and increased after SO removal ( P = .01 and P = .02, respectively). Outer retinal thicknesses did not vary among 3 time points ( P = .09). Conclusions: SO tamponade causes foveal flattening and thinning of the inner retinal layers, which is reversible on removal.


2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
YUKAKO OHYAMA ◽  
Hisateru Yamaguchi ◽  
Kazuki Nakajima ◽  
Daijo Inaguma ◽  
Midori Hasegawa ◽  
...  

Abstract Background and Aims Elevation of circulatory IgA1 with galactose-deficient (Gd) hinge-region (HR) O-glycans (Gd-IgA1) has been detected in most IgA nephropathy (IgAN) patients based on lectin ELISA. However, new approaches are needed for molecular-level characterization of IgA1 HR glycoform(s) in IgAN. We established a high-throughput method for analysis of IgA1 HR O-glycoforms using liquid chromatography-high-resolution mass spectrometry (LC-HRMS). To identify IgAN-associated IgA1 HR O-glycoforms and to assess their changes after therapy (with or without corticosteroids (CS)), we profiled IgA1 HR glycopeptides from sera collected at two time points (before and after therapy) from Japanese IgAN patients. Method Of the 10 Japanese IgAN patients recruited, 4 received CS treatment (CS group) and 6 have not (non-CS group). Japanese healthy volunteers (HC, n=10) were recruited as controls. Serum IgA1 was purified by affinity chromatography from HC and IgAN patients before and after therapy. After neuraminidase treatment and trypsin digestion, IgA1 HR glycosylation heterogeneity was analyzed by LC-HRMS. The relative abundance (RA, %) for each glycopeptide was calculated as percentage to the total IgA1 HR glycopeptide. The amount of each glycopeptide was then calculated by multiplying serum IgA concentration (mg/dL) by RA. Results Approximately 60% of IgA1 HR O-glycoforms in IgAN patients and HC were Gd O-glycoforms; these glycoforms contained one to three Gd-glycan(s), designated as 1 Gd-glycoform, 2 Gd-glycoform and 3 Gd-glycoform, respectively. In IgAN patients, the RA of non Gd-IgA1 glycoforms was elevated (P=0.002) and correlated with proteinuria (g/gCr) at renal biopsy (P=0.039, R=0.657). The amounts of non Gd- and 1Gd-glycoforms were higher in IgAN patients compared to HC (each P&lt;0.001). After several years of follow up (2.77 years (1.44-3.85)), the RA of non Gd-glycoforms decreased in CS group of IgAN patients (P=0.039) whereas it remained unchanged in the non-CS group (P=0.488). The amount of non Gd-glycoforms exhibited similar trends, i.e., decreased in CS group (P=0.068) whereas it remained unchanged in the non-CS group (P=0.943). Conclusion This study profiled serum IgA1 for IgAN-associated IgA1 HR O-glycoforms at the molecular level and assessed their changes in response to CS vs. non-CS therapy. IgA1 HR O-glycoforms altered by treatment may serve as a biomarker(s) for monitoring patients’ responses to therapy.


2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
Nihat Polat ◽  
Abuzer Gunduz

Purpose.To obtain information about effect of cycloplegia on keratometry and biometry in keratoconus.Methods.48 keratoconus (Group 1) and 52 healthy subjects (Group 2) were included in the study. We measured the flat meridian of the anterior corneal surface (K1), steep meridian of the anterior corneal surface (K2), lens thickness (LT), anterior chamber depth (ACD), and axial length (AL) using the Lenstar LS 900 before and after cycloplegia.Results.The median K1 in Group 1 was 45.64 D before and 45.42 D after cycloplegia, and the difference was statistically significant (P<0.05). The median K2 in Group 1 was 50.96 D before and 50.17 D after cycloplegia, and the difference was significant (P<0.05). The median K1 and K2 in Group 2 were 42.84 and 44.49 D, respectively, before cycloplegia, and 42.84 and 44.56 D after cycloplegia, and the differences were not statistically significant (allP>0.05). There were significant differences in SE, LT, ACD, and RLP between before and after cycloplegia in either Group 1 (allP<0.05) or Group 2 (allP<0.05). There were not statistically significant differences in AL between before cycloplegia and after cycloplegia in either Group 1 (P=0.533) or group 2 (P=0.529).Conclusions.Flattened corneal curvature and increase in ACD following cycloplegia in keratoconus patients were detected.


2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Xi Feng ◽  
Yong Wang ◽  
Jianheng Liang ◽  
Yali Xu ◽  
Julio Ortega-Usobiaga ◽  
...  

Objective. This study aimed to analyze the distribution of lens thickness (LT) and its associations in age-related cataract patients based on swept-source optical coherence tomography (SS-OCT). Methods. This cross-sectional study included 59,726 Chinese age-related cataract patients. Only right-eye data were included in the study. Repeated measures of ocular parameters were performed using an IOL Master 700 device. The distributions of ocular biometric data including anterior chamber depth (ACD), LT, axial length (AL), central corneal thickness (CCT), white-to-white (WTW), and mean keratometry (MK) and their associations with age were assessed. The anterior segment (AS) was measured as the sum of CCT, ACD, and LT, while the vitreous chamber depth (VCD) was calculated as the difference between AL and AS. The values of LT : AL, AS : AL, and VCD : AL in different AL groups and their changes are the main outcome measures used to observe the proportion of the anterior and posterior segments of the eye. Results. Biometric data were available for 59,726 individuals. The mean age was 68.81 years (range = 40–100); 40.62% were male and 59.38% were female. Mean anterior chamber depth (ACD) was 3.02 ± 0.44 mm, mean LT was 4.51 ± 0.44 mm, mean axial length (AL) was 23.89 ± 1.92 mm, mean central corneal thickness (CCT) was 0.53 ± 0.03 mm, mean white-to-white (WTW) was 11.64 ± 0.44 mm, and mean keratometry (MK) was 44.27 ± 1.65 diopter. Female patients had shorter AL, shallower ACD, smaller CCT and WTW, decreased LT, and steeper corneas ( p  < 0.005). ACD revealed the strongest negative correlation ( p  ≤ 0.001, r = –0.682) with LT. Age ( p  ≤ 0.001, r = 0.348) showed a moderate positive correlation, whereas MK ( p  < 0.05, r = 0.011), CCT ( p  ≤ 0.001, r = 0.041) had a weak positive correlation and WTW ( p  ≤ 0.001, r = –0.034) had a weak negative correlation with LT. A nonlinear correlation was found between LT and AL. LT increased with age in both males and females. LT changed variably in eyes with AL less than 27 mm, LT decreased as AL increased, then LT gradually increased as AL increased in extremely long and extra-long eyes ( p  ≤ 0.001). LT : AL and AS : AL decreased as AL increased, VCD : AL gradually increased as AL increased in highly myopic eyes, and VCD : AL increased by about 0.01 for every 1 mm increase in AL. Conclusions. Among Chinese age-related cataract patients, we found LT to have the strongest relation with ACD. The lens was thicker in elderly patients and women. The correlation between LT and AL is not a simple negative correlation; with the increase of age, LT decreases first and then increases. The proportion of VCD is constantly rising with the elongation of AL.


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