Evaluation of keratoconus progression and visual improvement after intrastromal corneal ring segments implantation: A retrospective study

2021 ◽  
pp. 112067212110006
Author(s):  
Bernardo Kaplan Moscovici ◽  
Pablo Felipe Rodrigues ◽  
Renan Albert Mendonça Rodrigues ◽  
Livia Cristina Rios ◽  
Rosangela Simoncelli ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Final Visit ◽  
Ocular Surgery ◽  
Post Surgery ◽  
Intrastromal Corneal Ring ◽  
Corrected Distance Visual Acuity ◽  
Ring Segment ◽  
Group 3

Objective: To investigate the role of ICRS in halting keratoconus progression in a large sample of patients. Methods: A retrospective, non-comparative, interventional study based on the review of medical records of patients diagnosed with keratoconus who underwent Ferrara corneal ring segment implantation. A retrospective chart analysis study of 123 operated eyes with follow-up ranging from 3 to 16 years (mean 5.3 ± 3.6 years) was performed. This study was carried out at Ocular Surgery Unit, São Paulo, Brazil. All topographic data were obtained from Pentacam (Oculus, Arlington, USA). The same surgeon performed all surgeries, and the Ferrara ICRS nomogram was used for ICRS selection in all cases. Results: Corrected distance visual acuity, keratometry, and topographic astigmatism improved in most cases, with statistical significance. In 42 eyes (53.8%), there was an increase in K1 or K2, and in 36 (46.2%), there was a reduction or maintenance in K1. Considering a difference higher than 1 D, between 3-month post-surgery and final visit (group 3), 32 eyes (41%) showed an increase, and 46 eyes (59%) ended equal or below this value. Conclusion: The implantation of ICRS showed improvement in visual and keratometric indexes. The majority of patients did not increase more than one diopter in keratometric values after ICRS implantation. ICRS may be effective for slowing disease progression, especially in older patients.

Outcomes of a 320-degree intrastromal corneal ring segment implantation for keratoconus: Results of a 6-month follow-up

2018 ◽  
Vol 30 (1) ◽  
pp. 139-146 ◽  
Author(s):  
Guilherme Andrade do Nascimento Rocha ◽  
Paulo Ferrara de Almeida Cunha ◽  
Leonardo Torquetti Costa ◽  
Luciene Barbosa de Sousa
Keyword(s):  
Visual Acuity ◽  
Spherical Equivalent ◽  
Distance Visual Acuity ◽  
Uncorrected Distance Visual Acuity ◽  
Intrastromal Corneal Ring ◽  
Corrected Distance Visual Acuity ◽  
Ring Segment ◽  
The Mean ◽  
Corneal Tomography

Importance: This study shows that a newer long-arc length intrastromal corneal ring segment is efficient and safe for keratoconus treatment. Background: To evaluate visual, tomographic results and complications of a 320-degree intrastromal corneal ring segment implantation with the femtosecond laser for keratoconus treatment. Design: A prospective, nonrandomized, and interventional study. Participants: A total of 34 eyes of 31 patients diagnosed with keratoconus were enrolled. Methods: Patients were divided into two groups based on the strategy used for 320-degree intrastromal corneal ring segment thickness selection. In one group, this selection was based on spherical equivalent (SE group) and in the other on the mean asphericity (Q group). The uncorrected and corrected distance visual acuities, spherical equivalent, K1, K2, Km, Kmax, and mean asphericity ( Q) on corneal tomography were evaluated preoperatively and at 3 and 6 months postoperatively. For astigmatism improvement, we analyzed the corneal tomographic vectorial astigmatism change preoperatively and at 6 months postoperatively. The mean follow-up period was 6.63 ± 0.96 months. Results: The mean uncorrected distance visual acuity and corrected distance visual acuity improved with a significant spherical equivalent improvement ( p < 0.05), with no differences between the 320-degree intrastromal corneal ring segment groups. All corneal tomographic parameters improved significantly ( p < 0.05) between the preoperative and postoperative intervals, with a significant better performance when we used spherical equivalent for the 320-degree intrastromal corneal ring segment thickness selection. Finally, the mean vectorial corneal tomographic astigmatism significantly improved after 6 months, again with no differences between groups. Conclusion: This study suggests that implanting a 320-degree intrastromal corneal ring segment is a safe and effective procedure for treating patients with keratoconus. It also suggests that for thickness selection spherical equivalent is the better strategy.

Three-year follow-up of intrastromal corneal ring segment implantation in central keratoconus with regular astigmatism: ‘Bow-tie’ shape

2019 ◽  
Vol 30 (4) ◽  
pp. 643-649 ◽  
Author(s):  
Luis Fernández-Vega-Cueto ◽  
Carlos Lisa ◽  
Aranzazu Poo-López ◽  
José F Alfonso ◽  
David Madrid-Costa
Keyword(s):  
Visual Acuity ◽  
Postoperative Period ◽  
Spherical Equivalent ◽  
Distance Visual Acuity ◽  
Post Surgery ◽  
Uncorrected Distance Visual Acuity ◽  
Intrastromal Corneal Ring ◽  
Corrected Distance Visual Acuity ◽  
Bow Tie

Purpose: To assess the outcomes of implanting Ferrara-type intrastromal corneal ring segments in central ‘bow-tie’-shaped keratoconus over 3 years of follow-up. Methods: A total of 20 eyes with central ‘bow-tie’-shaped keratoconus were evaluated before and after implanting Ferrara-type intrastromal corneal ring segments (AJL Ophthalmic, Spain). LogMAR uncorrected distance visual acuity and best corrected distance visual acuity and residual refractive errors analysed using vector analysis were recorded preoperatively, at 6 months, 1 year, and 3 years postoperatively. Results: The mean uncorrected distance visual acuity (LogMAR scale) rose from a preoperative 0.75 ± 0.28 to a 6-month postoperative 0.38 ± 0.28 (p < 0.0001). The corrected distance visual acuity, in turn, improved from 0.07 ± 0.06 to 0.05 ± 0.06 (p = 0.0008). Both the uncorrected distance visual acuity and corrected distance visual acuity were stable over the postoperative period in both groups (p > 0.05). None of the eyes lost uncorrected distance visual acuity and corrected distance visual acuity lines over the postoperative follow-up period. The spherical equivalent and the refractive cylinder declined steeply after intrastromal corneal ring segments implantation (p < 0.0001). Both the spherical equivalent and refractive cylinder were stable over the postoperative period. None of the eyes had an increase in maximum or minimum keratometry greater than 0.75D over the postoperative period. Conclusion: The planning for intrastromal corneal ring segments insertion proposed in this study reduces the spherical equivalent and refractive cylinder in this type of keratoconus, while improving post-surgery uncorrected distance visual acuity and corrected distance visual acuity. These results remain stable over 3 years of follow-up. Therefore, this procedure could be considered as an effective therapeutic alternative in patients affected by this type of keratoconus.

Intrastromal corneal ring segment implantation in paracentral keratoconus with perpendicular topographic astigmatism and comatic axis

2020 ◽  
pp. 112067212095234
Author(s):  
Luis Fernández-Vega-Cueto ◽  
Carlos Lisa ◽  
Belén Alfonso-Bartolozzi ◽  
David Madrid-Costa ◽  
José F Alfonso
Keyword(s):  
Statistical Significance ◽  
Arc Length ◽  
Refractive Outcomes ◽  
Group I ◽  
Intrastromal Corneal Ring ◽  
Before And After ◽  
Ring Segment ◽  
Group Ii ◽  
Topographic Astigmatism

Purpose: To evaluate the outcomes of implanting intrastromal corneal ring segment (ICRS) using two different strategies in a specific paracentral keratoconus phenotype. Methods: Eighty-nine eyes with paracentral keratoconus with perpendicular topographic astigmatism and comatic axes were evaluated before and after implanting a 150° arc-length ICRS. Patients were divided into two groups according to the axis where the ICRS was implanted: Group I: comatic axis and Group II: flat topographic axis. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refractive errors, and root mean square (RMS) for coma-like aberration were recorded. The postoperative follow-up was 1 year. Results: Mean UDVA (logMAR) changed from 0.49 ± 0.37 preoperatively to 0.30 ± 0.32 6 months afterwards ( p < 0.001) in the group I and from 0.53 ± 0.34 to 0.37 ± 0.35 ( p < 0.001), in the group II. Mean CDVA in group I changed from 0.11 ± 0.18 preoperatively to 0.06 ± 0.14 6 months after surgery ( p < 0.001). In group II the improvement did not reach statistical significance (from 0.09 ± 0.10 to 0.07 ± 0.09; p = 0.06). No eyes lost lines of CDVA in group I. Eight eyes (15.7%) lost lines of CDVA in group II. The spherical equivalent decreased after surgery in both groups ( p < 0.001). The RMS for corneal coma-like aberration only decreased in the group I ( p < 0.001). Conclusion: Both strategies provided safe and effective visual and refractive outcomes in the specific keratoconus phenotype analyzed. The orthopedic strategy provided better visual outcomes than the refractive one.

scholarly journals Evaluation of a new nomogram for Ferrara ring segment implantation in keratoconus

2021 ◽  
Vol 14 (9) ◽  
pp. 1371-1383
Author(s):  
Joaquín Fernández ◽  
◽  
Antonio Pérez-Rueda ◽  
Sidi Mohamed Hamida Abdelkader ◽  
María José Roig-Revert ◽  
...  
Keyword(s):  
Short Term ◽  
Visual Rehabilitation ◽  
Corrected Distance Visual Acuity ◽  
Ring Segment ◽  
Mechanical Procedure ◽  
Corneal Asphericity ◽  
Refractive Change ◽  
Prospective Longitudinal ◽  
Coma Aberration

AIM: To evaluate the short-term clinical outcomes of Ferrara rings in keratoconus using an optimized nomogram developed after several years of research and retrospective analysis of clinical data. METHODS: This prospective longitudinal non-comparative clinical trial evaluated 88 eyes of 88 patients (age 18-62y) with keratoconus diagnosis from two Spanish centers. Ferrara ring segment (AJL Ophthalmic) implantation was performed in all cases, using the mechanical procedure in 25 eyes (28.4%) and a femtosecond laser-assisted procedure in 63 eyes (71.6%). The ring segments implanted in each case were selected using a new optimized nomogram that considered variables such as anterior corneal asphericity and astigmatism or the discrepancy among astigmatism and coma orientations. Visual, refractive, corneal topographic, aberrometric, and pachymetric changes after surgery were evaluated during a 3-month follow-up. RESULTS: The implants induced a significant refractive change as well as an improvement in uncorrected (UDVA) and corrected distance visual acuity (CDVA; P<0.001). Postoperative CDVA of 0.10 logMAR or better was achieved in 28.4% and 46.5% of eyes, respectively. Two eyes (2.3%) lost two or more lines of CDVA whereas a total of 53.5% of eyes gained lines of CDVA. A significant central anterior and posterior corneal flattening was induced (P≤0.003), with a significant reduction of anterior (P<0.001) and posterior corneal astigmatisms (P=0.048), and a change in anterior asphericity (P<0.001). Total primary coma (6 mm pupil) change was also statistically significant (preoperative 3.66±3.04 µm vs postoperative 2.33±2.26 µm, P<0.001). No significant differences were found in the effect of ring segments between cases implanted using the mechanical and femtosecond techniques (P≥0.101). CONCLUSION: The implantation of Ferrara rings based on the nomogram evaluated is safe and effective for promoting a visual rehabilitation in keratoconus, with a relevant control of primary coma aberration.

Role of ctDNA to predict risk of recurrence following potentially curative resection of biliary tract and pancreatic malignancies.

2021 ◽  
Vol 39 (3_suppl) ◽  
pp. 336-336
Author(s):  
Angela Lamarca ◽  
Mairead Geraldine McNamara ◽  
Richard Hubner ◽  
Juan W. Valle
Keyword(s):  
Relapse Rate ◽  
Curative Resection ◽  
Cox Regression ◽  
Statistical Significance ◽  
Molecular Profiling ◽  
P Value ◽  
Relapse Risk ◽  
Baseline Characteristics

336 Background: The potential role of ctDNA to identify residual disease after potentially curative resection has been suggested in some malignancies; its role in resected pancreatico(P)-biliary(B) malignancies is unknown. Methods: Patients diagnosed with PB malignancies underwent molecular profiling (ctDNA) using FoundationMedicine Liquid (72 cancer-related genes) following potentially curative resection. Baseline patient characteristics and molecular profiling outcomes, including mutant allele frequency (MAF) for pathological alterations were extracted. Primary objective: prevalence of ctDNA identification and its correlation with recurrence (relapse-free survival (RFS) and relapse rate). Results: Total of 11 individuals had ctDNA analysed following potentially curative resection for PB malignancies: 8 B (4 extra-hepatic cholangiocarcinoma (eCCA), 2 ampulla, 1 intrahepatic cholangiocarcinoma (iCCA), 1 gallbladder cancer (GBC)) and 3 P. Baseline characteristics: 6 female (54.55%), median age 71.59 years (range 39.98-81.19). Most were pT2 (45.45%), pN0 (54.55%) and R0 (63.64%). Following surgery, 6 patients were started on adjuvant chemotherapy; at the end of follow-up (data cut-off 25/6/2020; median follow-up 11.15 months (range 5.45-13.52); 5 relapsed (45.45%) and 2 died (18.18%). Estimated median RFS was 11.43 months (95% CI 2.28-not reached); median overall survival was not reached. No sample failed ctDNA analysis; presence of ctDNA was identified in 3/11 (27.27%) of the samples; 2 and 1 samples had 2 and 1 pathological alterations identified, respectively: ALK fusion (1 sample; GBC), TP53 mutation (2 samples; eCCA and GBC), CHEK2 mutation (1 sample; pancreas), IDH2 mutation (1 sample; eCCA). Mean maximum MAF was 1.47 (2 in biliary; 0.43 in pancreas). Variants of unknown significance were identified in 72.73% of the samples (87.5% in B; 33.33% in P; p-value 0.152). None of the baseline characteristics explored correlated with presence of ctDNA. There was a trend towards increased relapse risk in the patients with ctDNA present following potentially curative surgery; Cox regression for RFS [HR 2.64 (95% CI 0.36-19.31); median RFS 11.44 months (95% CI 2.28-not reached) vs 10.87 (95% CI 2.21-not reached)]; relapse rate 37.5% (ctDNA absent) vs 66.67% (ctDNA present); statistical significance was not reached (p-value 0.340 and p-value 0.545, respectively). Conclusions: This pilot study demonstrates the feasibility of testing for ctDNA following potentially curative resection in PB malignancies. Presence of ctDNA may be associated with increased relapse risk; further studies are required to increase sample size and assess clinical implications.

scholarly journals 1129. Targeted Voriconazole Prophylaxis in Heart Transplantation Recipients

2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S338-S338
Author(s):  
Michael Lin ◽  
Ignacio Echenique ◽  
Michael Angarone ◽  
Allen Anderson ◽  
Valentina Stosor
Keyword(s):  
Heart Transplantation ◽  
Fungal Infections ◽  
Single Case ◽  
Statistical Significance ◽  
Antifungal Prophylaxis ◽  
Observational Cohort Study ◽  
Observational Cohort ◽  
Univariate Analyses

Abstract Background The use of antifungal prophylaxis, targeted or universal, remains controversial and unstudied. The goal of this study is to determine the role of targeted voriconazole prophylaxis (VORI) in prevention of invasive fungal infections (IFI) after heart transplantation (HT). Methods We conducted a single-center, prospective, observational cohort study of 276 HT recipients from June 2005 to April 2017 to characterize the incidence and outcome of IFI following targeted VORI. Starting in June 2013, HT recipients with thymoglobulin (ATG) treatment received VORI for 3 months. Probable/proven IFI were defined by EORTC/MSG criteria. Descriptive frequencies and univariate analyses were performed. Results Mean duration of follow-up post-HT was 1,165 days (0–3,152 days). 149 (54%) and 70 (25%) received basiliximab and thymoglobulin induction, respectively. Thirty-one (11%) received VORI, following use of ATG in the setting of induction (68%) or rejection (32%). VORI was started at median of 6 days (0–1,008 days) post-HT for a mean duration of 97 days (5–251 days). Overall, 23 IFIs occurred in 23 recipients (8%) at mean 283 days post-HT (range 2–1,579 days), including seven Aspergillus (one occurring after VORI completion), seven invasive Candida (five with candidemia), two Rhizopus, one Cunninghamella, two histoplasma, two blastomyces, one Cryptococcus, and one multifocal cutaneous Alternaria. Conclusion Targeted VORI resulted in reduced incidences of both early and overall IFI after HT although this did not reach statistical significance. Since instituting this strategy, we have observed a single case of aspergillosis following VORI discontinuation. Overall and 1-year mortality were not impacted. The use of antifungal prophylaxis following HT requires continued investigation both to determine efficacy and toxicity in this patient population. Disclosures All authors: No reported disclosures.

scholarly journals P303 Role of parietal healing by ultrasound in the evolution of patients with Crohn’s disease

2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S304-S305
Author(s):  
P Mayor Delgado ◽  
C J Suarez Ferrer ◽  
J Poza Cordon ◽  
E Martin Arranz ◽  
J L Rueda Garcia ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Survival Analysis ◽  
Crohn's Disease ◽  
Median Survival ◽  
Statistical Significance ◽  
Inflammatory Activity ◽  
First Year ◽  
Ultrasound Findings

Abstract Background The objective of this study is to assess the degree of parietal involvement with ultrasound and see how they influence the prognosis according to the findings. Methods It was defined as ‘parietal healing’ the normalisation of ultrasound findings in a previously affected segment (parietal thickness less than 3 mm and absence of parietal hyperaemia). Therefore, patients with absence of ultrasound activity but without reaching parietal healing were considered to be those without significant inflammatory signs (parietal thickness &lt;4.5 mm and absence of hyperaemia or other inflammatory data) but who had not ‘normalised’ the previously affected segment. Results A total of 111 patients without ultrasound inflammatory activity were included. It was studied whether normalisation of parameters in a previously affected segment, i.e. parietal healing gave a better prognosis during follow-up. It was detected that 74 patients achieved ‘parietal healing’ and this subgroup of patients generally had a flare in 12% of cases (9/74 patients) compared with 27% of cases (10/37) among patients without parietal healing, these differences were statistically significant (p = 0.05). Similar, it was identified that among patients without ultrasound activity who had a subsequent outbreak during follow-up, the median survival was lower (1,09 years) in patients without parietal healing vs. those with parietal healing (1.4 years), the differences reaching statistical significance (p = 0.03). Likewise, during the follow-up, it was objectived, by means of survival analysis, that the evolution of patients without ultrasound activity was more favourable in those with ‘parietal healing’ with remission 95% vs. 90% at first year, 89% vs. 81% at 2 years and 85% vs. 66% at 3 years of follow-up. The results are outlined in Figure 1. Conclusion To conclude, detecting parietal healing by ultrasound improves prognosis by decreasing the number of outbreaks and increasing the median survival until outbreaks occur.

Tamoxifen (T) compared to placebo (P), after adjuvant chemotherapy (CT), in premenopausal women with early breast cancer (EBC): Interim results of NCIC-CTG MA.12

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 547-547 ◽  
Author(s):  
V. H. Bramwell ◽  
K. I. Pritchard ◽  
D. Tu ◽  
K. Tonkin ◽  
H. Vachhrajani ◽  
...  
Keyword(s):  
Meta Analysis ◽  
Disease Free Survival ◽  
Premenopausal Women ◽  
Free Survival ◽  
Post Surgery ◽  
Improved Outcomes ◽  
Stopping Treatment ◽  
Safety Monitoring Committee

547 Background: In the early 1990’s, the role of adjuvant T in premenopausal women with EBC had not been clearly established. The efficacy of adjuvant T in hormone receptor (H) negative EBC was unclear. Methods: Eligible premenopausal women with node (N) +ve/high risk N -ve EBC, any H status, post surgery, received standard adjuvant CT (AC ×4, CMF ×6, CEF x6) then were randomized to T (20 mg/day) or P for 5 yrs. Overall survival (OS), disease-free survival (DFS) and toxicity/compliance were evaluated. Original sample size was 800 pts but based on slow accrual was reduced to 660. Mortality rate is lower than anticipated, and Data Safety Monitoring Committee approved reporting results after second interim analysis (152 deaths). Results: 1993–2000, 672 women randomized, median follow-up 8.4 yrs. For T vs P, 5 yr OS 87% vs 82% [Hazard Ratio HR 0.81 (95% CI 0.58–1.12), p = 0.19] and 5 yr DFS 78% vs 71% [HR 0.79 (95% CI 0.61–1.03), p = 0.09]. HR for OS (0.87 vs 0.78, p = 0.71) and DFS (0.79 vs 0.77, p = 0.87) were not significantly different for H +ve and H -ve tumors respectively. Compliance with T/P was suboptimal, 29% women stopping treatment within 2 yrs, and only 53% completing 5 yrs. Conclusions: Current results show only a trend towards improved DFS for premenopausal women with EBC who receive T after adjuvant CT. Other studies of similar design have shown improved DFS, but not OS, and meta-analysis may be more informative. Issues affecting results (slow accrual, improved outcomes for EBC, poor compliance, additional therapies) will be discussed. [Table: see text] [Table: see text]

Gamma Knife surgery for cerebral arteriovenous malformations in children: a 13-year experience

2008 ◽  
Vol 1 (4) ◽  
pp. 296-304 ◽  
Author(s):  
David Hung-Chi Pan ◽  
Yu-Hung Kuo ◽  
Wan-Yuo Guo ◽  
Wen-Yuh Chung ◽  
Hsiu-Mei Wu ◽  
...  
Keyword(s):  
Gamma Knife ◽  
Pediatric Patients ◽  
Pediatric Population ◽  
Statistical Significance ◽  
Adult Population ◽  
Gamma Knife Surgery ◽  
Morbidity Rate ◽  
Obliteration Rate

Object Studies on the efficacy of arteriovenous malformation (AVM) radiosurgery have largely been conducted in the adult population. Clinically, the results may not always be applicable to pediatric patients. Moreover, studies involving the pediatric population have largely comprised small- (< 3 cm3) and medium-sized (3–10 cm3) AVMs. For large (> 10 cm3) AVMs in children, sparse radiosurgical results are available. The current study was conducted to further clarify the role of radiosurgery in the treatment of pediatric AVMs. Methods A retrospective analysis was performed of data obtained in 105 pediatric patients (< 18 years of age) with cerebral AVMs treated by Gamma Knife surgery (GKS) between 1993 and 2006. For statistical comparison the authors studied data acquired in 458 adult patients with AVMs treated during the same period. The patients underwent follow-up magnetic resonance imaging at 6-month intervals. Cerebral angiography was used to confirm the obliteration of the AVM. Results In pediatric patients, the AVM obliteration rate at 48 months after a primary GKS was 65%. Repeated GKS in those in whom primary treatments failed further ablated some AVMs, for an overall obliteration rate of 81%. The efficacy of GKS correlated with the size of the AVM: 91% for small, 86% for medium, and 64% for large AVMs. The treatments were associated with an 8% morbidity rate and < 1% mortality rate. Posttreatment hemorrhage occurred in 4 (4%) of 105 patients. Obliteration rates at 48 months of small and extremely large (> 20 cm3) AVMs were similar in the pediatric and adult groups, whereas AVMs between 3 and 10 cm3 responded less efficaciously in children (p = 0.042). The AVMs with volumes ranging from 10 to 20 cm3 were also associated with a lower obliteration rate in children at 48 months, but statistical significance was not reached (p = 0.279). Conclusions Gamma Knife surgery is an effective and safe treatment alternative for pediatric AVMs. The medium (3–10-cm3) and large (10–20-cm3) AVMs tend to respond less efficaciously than those of comparable size in adults.

scholarly journals Intrastromal Corneal Ring Segments for Astigmatism Correction after Deep Anterior Lamellar Keratoplasty

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Júlio C. D. Arantes ◽  
Sandro Coscarelli ◽  
Paulo Ferrara ◽  
Luana P. N. Araújo ◽  
Marcos Ávila ◽  
...  
Keyword(s):  
Contact Lenses ◽  
Corneal Astigmatism ◽  
Lamellar Keratoplasty ◽  
Deep Anterior Lamellar Keratoplasty ◽  
Spherical Equivalent ◽  
Astigmatism Correction ◽  
Intrastromal Corneal Ring ◽  
Anterior Lamellar Keratoplasty ◽  
Corrected Distance Visual Acuity ◽  
Ring Segment

Background. To evaluate the change in corneal astigmatism after intrastromal corneal ring segment (ICRS) implantation in keratoconus patients with previous deep anterior lamellar keratoplasty (DALK). Design was a longitudinal, retrospective, interventional study. The study included 25 eyes of 24 patients with keratoconus who had DALK performed at least two years prior to ICRS implantation. All patients had a clear corneal graft with up to 8.00 D of corneal astigmatism and intolerance to contact lenses. The studied parameters were age, sex, corrected distance visual acuity (CDVA), maximum keratometry (K1), minimum keratometry (K2), spherical equivalent, and astigmatism. There was a statistically significant decrease in the postintervention analysis as follows: 3.5 D reduction in K1 (p<0.001); 1.53 D in K2 (p=0.005); and 2.52 D (p<0.001) in the average K. The spherical equivalent reduced from −3.67 D (±2.74) to −0.71 D (±2.35) (p<0.001). The topographic astigmatism reduced from 3.87 D preoperatively to 1.90 D postoperatively (p<0.001). The CDVA improved from 0.33 (±0.10) to 0.20 (±0.09, p<0.001). ICRS implantation is a useful option for the correction of astigmatism after DALK as it yields significant visual, topographic, and refractive results.

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