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1.
Zhonghua Yan Ke Za Zhi ; 57(10): 796-800, 2021 Oct 11.
Artigo em Chinês | MEDLINE | ID: mdl-34619953

RESUMO

Artificial intelligence (AI) has made important progress in image recognition and disease prognosis prediction in recent years. Along with the development of computer technology, the application scope of AI in the field of ophthalmology is expanding. Keratoconus screening is an important means to determine the indication of refractive surgery and avoid postoperative corneal ectasia, but the accuracy of traditional diagnostic methods is low, especially for subclinical keratoconus. Machine learning, a method to realize artificial intelligence, makes it possible to improve the accuracy of keratoconus screening, and has become a hotspot in the field of refractive surgery recently. The review has clarified the algorithms commonly used in keratoconus screening for refractive surgery, the extraction of corneal features, and the accuracy of model prediction.(Chin J Ophthalmol, 2021, 57: 796-800).


Assuntos
Ceratocone , Oftalmologia , Procedimentos Cirúrgicos Refrativos , Inteligência Artificial , Humanos , Ceratocone/diagnóstico , Ceratocone/cirurgia , Aprendizado de Máquina
2.
BMC Ophthalmol ; 21(1): 357, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34625056

RESUMO

BACKGROUND: Keratoconus is a chronic degenerative disorder of the cornea characterized by thinning and cone-shaped protrusions. Although genetic factors play a key role in keratoconus development, the etiology is still under investigation. The occurrence of single-nucleotide polymorphisms (SNPs) associated with keratoconus in Russian patients is poorly studied. The purpose of this study was to validate whether three reported keratoconus-associated SNPs (rs1536482 near the COL5A1 gene, rs2721051 near the FOXO1 gene, rs1324183 near the MPDZ gene) are also actual for a Russian cohort of patients. Additionally, we investigated the COL5A1 promoter sequence for single-nucleotide variants (SNVs) in a subgroup of keratoconus patients with at least one rs1536482 minor allele (rs1536482+) to assess the role of these SNVs in keratoconus susceptibility associated with rs1536482. METHODS: This case-control study included 150 keratoconus patients and two control groups (main and additional, 205 and 474 participants, respectively). We performed PCR targeting regions flanking SNVs and the COL5A1 promoter, followed by Sanger sequencing of amplicons. The additional control group was genotyped using an SNP array. RESULTS: The minor allele frequency was significantly different between the keratoconus and control cohorts (main and combined) for rs1536482, rs2721051, and rs1324183 (p-value < 0.05). The rare variants rs1043208782 and rs569248712 were found in the COL5A1 promoter in two out of 94 rs1536482+ keratoconus patients. CONCLUSION: rs1536482, rs2721051, and rs1324183 were associated with keratoconus in a Russian cohort. SNVs in the COL5A1 promoter do not play a major role in keratoconus susceptibility associated with rs1536482.


Assuntos
Colágeno Tipo V , Ceratocone , Estudos de Casos e Controles , Colágeno Tipo V/genética , Predisposição Genética para Doença , Humanos , Ceratocone/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
3.
BMC Ophthalmol ; 21(1): 317, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465309

RESUMO

INTRODUCTION: We present seven cases of infectious keratitis after corneal crosslinking (CXL) to attenuate keratoconus progression. METHODS: Of 524 consecutive patients who underwent CXL, 7 cases (4 males and 3 females; 21.5 ± 7.1 years) developed postoperative infectious keratitis were retrospectively reviewed. CXL was performed using the Dresden protocol or an accelerated protocol involving epithelial removal. RESULTS: All cases appeared normal on the day after surgery, but subsequently developed eye pain, blurred vision, corneal infiltration, inflammation of the anterior chamber, and ciliary injection on day 2 or 3. Methicillin-resistant Staphylococcus aureus was cultured from two eyes, methicillin-sensitive Staphylococcus aureus from two eyes, and Streptococcus pneumoniae from one eye. All detected bacteria were resistant to levofloxacin (LVFX). Five of the seven cases, especially four of the five severe cases with hypopyon, had a history of atopic dermatitis. All cases were observed after 2015. CONCLUSIONS: Infectious keratitis after CXL caused by microbes resistant to LVFX is increasing. In addition to careful postoperative observation of the cornea, preoperative evaluation of bacteria within the conjunctival sac evident on nasal swab cultures may be useful to identify potentially problematic microbes and inform the selection of appropriate antibiotics.


Assuntos
Ceratite , Ceratocone , Staphylococcus aureus Resistente à Meticilina , Córnea , Reagentes para Ligações Cruzadas , Feminino , Humanos , Ceratite/tratamento farmacológico , Ceratocone/tratamento farmacológico , Levofloxacino/uso terapêutico , Masculino , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico
4.
J Refract Surg ; 37(9): 623-630, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34506244

RESUMO

PURPOSE: To compare the clinical and tomographic properties of adult patients with keratoconus treated with accelerated corneal cross-linking (A-CXL) versus accelerated contact lens-assisted corneal cross-linking (A-CACXL). METHODS: Patients who underwent A-CXL and A-CACXL due to progressive keratoconus were enrolled from January 2015 to January 2018 in this retrospective case-control study. The treatment group (minimum corneal thickness of less than 400 µm after epithelium removal; 30 patients, 30 eyes) was treated with A-CACXL; the control group (minimum corneal thickness of 400 µm or greater, 32 patients, 32 eyes) was treated with A-CXL. Assessments occurred before treatment and 12 months postoperatively. Demographic, clinical, and tomographic data were obtained from outpatient clinic reports. RESULTS: Significant improvement in visual acuity was evident at 12-month follow-up for the control group in uncorrected distance visual acuity (0.62 ± 0.42 vs 0.43 ± 0.31 logMAR, P = .01) and the treatment group in corrected distance visual acuity (0.51 ± 0.30 vs 0.40 ± 0.49 logMAR, P = .03). Progression of keratoconus was halted at similar rates for both groups (76.7% treatment, 84.4% control, P = .21). Mean minimum corneal thickness showed minor but significant thinning at the 12-month follow-up visit compared to baseline (control group = 463 ± 31 vs 450 ± 35 µm, P > .01; treatment group = 398 ± 32 vs 388 ± 41 µm, P = .02). CONCLUSIONS: A-CACXL halted keratoconus progression in 76.7% of eyes and achieved regression in 33.3% of eyes, with rates comparable to A-CXL. Visual outcomes improved for both groups, with similar keratometry changes. A-CACXL is an effective and safe option for patients with keratoconus and thin corneas, with results similar to A-CXL treatment in patients with a minimum corneal thickness of 400 µm or greater. [J Refract Surg. 2021;37(9):623-630.].


Assuntos
Lentes de Contato , Ceratocone , Fotoquimioterapia , Adulto , Estudos de Casos e Controles , Colágeno/uso terapêutico , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Seguimentos , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico , Raios Ultravioleta
5.
Cesk Slov Oftalmol ; 77(4): 184-189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34507494

RESUMO

AIM: To evaluate the effect of crosslinking (CXL) therapy on the change in the quality of visual acuity and the change in the topographic properties of the cornea - curvature, pachymetry, and change of astigmatism, coma abberation and CLMIaa (Cone Localisation and Magnitude Index). METHODS: A retrospective analytical study included 29 eyes of 24 patients who had progressed in the last 12 months and were suitable candidates for CXL surgery. The monitored parameters were the steepest, flatest and mean anterior instantaneous curvature (AICS, AICF, AICM) and the steepest, flatest and mean posterior instantaneous curvature (PICS, PICF, PICM) of the cornea, corneal thickness in the centre of the cornea (PACHC) and in the thinnest point of the cornea (PACHT), corneal astigmatism (ASTIG). coma (COMA), Cone Localization and Magnitude Index (CLMIaa) and uncorrected distance visual acuity (UDVA) with corrected distance visual acuity (CDVA). Data were analysed before surgery and 12 months after surgery. The AIC, COMA, CLMIaa and ASTIG parameters were analysed by paired t test. As the parameters of UDVA, CDVA, PIC and PACH did not meet the conditions of normal distribution, the Wilcoxon test was used to investigate the change in these parameters after CXL. RESULTS: Twelve months after the procedure, we recorded an improvement in UDVA (p = 0.371) and CDVA (p = 0.825), an increase in PICS, PICF and PICM (p = 0.902; p = 0.87 and p = 0.555), a decrease in PACHCC (p = 0.294) and a decrease in CLMIaa (p = 0.113) that did not reach statistical significance. The decrease in PACHT (p = 0.027), decrease in COMA (p = 0.037) and decrease in anterior corneal curvature of AICS, AICF and AICM were statistically significant (p = 0.019; p = 0.010 and p = 0.005). The decrease in the value of astigmatism did not show statistical significance, as p = 0.297. CONCLUSION: CXL corneal therapy has been shown to be an effective method to stabilize the cornea in progressive keratoconus, and to improve the higher order of coma. This contributes to the possible improvement of UDVA and CDVA.


Assuntos
Ceratocone , Colágeno , Córnea , Substância Própria , Topografia da Córnea , Reagentes para Ligações Cruzadas , Humanos , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Riboflavina/uso terapêutico , Acuidade Visual
6.
BMC Ophthalmol ; 21(1): 339, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544392

RESUMO

BACKGROUND: In vivo corneal biomechanics evaluation has been used to help screen early keratoconus in recent years. This study is to evaluate the value of a Scheimpflug-based biomechanical analyser combined with tomography in detecting subclinical keratoconus by distinguishing normal eyes from frank keratoconus (KC) and forme frusta keratoconus (FFKC) eyes in Chinese patients. METHODS: Study design: diagnostic test. This study included 31 bilateral frank keratoconus patients, 27 unilateral clinically manifesting keratoconus patients with very asymmetric eyes, and 79 control subjects with normal corneas. Corneal morphological and biomechanical parameters were measured using a Pentacam HR and a Corvis ST (OCULUS, Wetzlar, Germany). The diagnostic ability of computed parameters reflecting corneal biomechanical and morphological traits [including the Belin-Ambrósio deviation index (BAD_D), the Corvis biomechanical index (CBI) and the tomographic and biomechanical index (TBI)] was determined using receiver operating characteristic (ROC) curve analysis and compared by the DeLong test. Additionally, the area under the curve (AUC), the best cut-off values, and the Youden index for each parameter were reported. A novel corneal stiffness parameter, the stress-strain index (SSI), was also compared between KC, FFKC and normal eyes. RESULTS: Every morphological and biomechanical index analysed in this study was significantly different among KC, FFKC and normal eyes (P = 0.000). The TBI was most valuable in detecting subclinical keratoconus (FFKC eyes), with an AUC of 0.928 (P = 0.000), and both forms of corneal ectasia (FFKC and frank KC eyes), with an AUC of 0.966 (P = 0.000). The sensitivity and specificity of the TBI was 97.5 and 77.8 % in detecting FFKC and 97.5 and 89.7 % in detecting any KC, respectively, with a cut-off value of 0.375. The morphological index BAD_D and the biomechanical index CBI were also very useful in distinguishing eyes with any KC from normal eyes, with AUCs of 0.965 and 0.934, respectively. The SSI was significantly different between KC, FFKC and normal eyes (P = 0.000), indicating an independent decrease in corneal stiffness in KC eyes. CONCLUSIONS: The combination of a Scheimpflug-based biomechanical analyser and tomography could increase the accuracy in detecting subclinical keratoconus in Chinese patients. The TBI was the most valuable index for detecting subclinical keratoconus, with a high sensitivity and specificity. Evaluation of corneal biomechanical properties in refractive surgery candidates could be helpful for recognizing potential keratoconic eyes and increasing surgical safety.


Assuntos
Ceratocone , Fenômenos Biomecânicos , China/epidemiologia , Córnea , Topografia da Córnea , Humanos , Ceratocone/diagnóstico , Curva ROC , Tomografia
7.
J Clin Ethics ; 32(3): 271-273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34548436

RESUMO

In pediatric cohort studies, disclosing findings and providing treatment counseling to parents, legal guardians, or other authorized representatives is an ethical imperative. Keratoconus (KC) is a corneal degenerative disease that can progress to severe vision impairment and need for corneal transplantation. This report concerns the disclosure of results to the parents of children who were diagnosed with KC in the Shahroud Schoolchildren Eye Cohort Study and received essential treatment in a timely manner.


Assuntos
Ceratocone , Saúde Pública , Criança , Estudos de Coortes , Córnea , Topografia da Córnea , Humanos
8.
Vestn Oftalmol ; 137(4): 90-97, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34410062

RESUMO

Optical correction of keratoconus (KC) is intended to simultaneously solve two tasks: elimination of myopic defocus and irregular astigmatism. In terms of the latter, hard contact lenses (HCL) should be considered as the first-choice method for optical correction of KC. HCL are currently the most effective means of optical correction of refractive errors induced by KC. Despite this, it should be noted that adherence of patients to this method of correction does not always correspond to results. Most often, limitations of HCL use in KC are associated with the so-called intolerance of correction. The term «correction intolerance¼ should be considered as a general complex of potential subjective symptoms and clinical manifestations that limit the possibility of using a particular method of optical correction. In this clinical observation, subjective discomfort when wearing lenses was practically eliminated by changing the design of the lens and switching from corneal to scleral HCL. The second problem was caused by clinical manifestations of corneal hypoxia (growth of newly formed vessels in the limbal region of the cornea) and attempts to solve it were associated with improved tear production and increased oxygen permeability of the material HCL are made of. The observed stabilization of the growth of newly formed vessels should be considered as a positive (although in need of dynamic evaluation) result of these therapeutic measures.


Assuntos
Astigmatismo , Lentes de Contato , Ceratocone , Erros de Refração , Lentes de Contato/efeitos adversos , Córnea , Humanos , Ceratocone/diagnóstico , Ceratocone/etiologia , Ceratocone/terapia
9.
Indian J Ophthalmol ; 69(9): 2430-2435, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34427237

RESUMO

Purpose: The keratoconus end-points assessment questionnaire (KEPAQ) is a disease-specific scale designed to evaluate the quality of life in keratoconus patients and provides the measurement of both functional and emotional compromise in keratoconus. It was previously developed, tested, and validated and now we want to evaluate the test-retest reliability of the KEPAQ, in an effort to contribute evidence on its internal consistency and capability of measuring clinical state with minimal inference of random chance. Methods: This is a prospective analytical study, designed to evaluate the test-retest reliability of the KEPAQ through the repeated application of the questionnaire to a group of clinically stable individuals. A number of patients with a confirmed diagnosis of keratoconus underwent double application of the KEPAQ, seven days apart. Mean KEPAQ score was obtained through Rasch analysis, while test-retest reliability was evaluated through Spearman rank-order correlation and intraclass correlation coefficient. Rasch analysis was performed in JMetrik version 4.1.1 (Psychomeasurement Systems LLC; Charlottesville, VA, USA) in a MacBook Air computer running macOS Catalina version 10.15.2 (Apple Inc.; Cupertino, CA, USA). Results: A total of 100 patients were included. For KEPAQ-E, Spearman correlation was R = 0.963 while ICC was 0.981 (95% confidence interval 0.972-0.987). For KEPAQ-F, Spearman correlation was R = 0.921 while ICC was 0.952 (95% confidence interval 0.929-0.968). Conclusion: The KEPAQ is a robust, well-developed, extremely reliable scale which can be confidently used for clinical and research endeavors.


Assuntos
Ceratocone , Qualidade de Vida , Humanos , Ceratocone/diagnóstico , Ceratocone/epidemiologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Inquéritos e Questionários
11.
J Refract Surg ; 37(8): 552-561, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34388067

RESUMO

PURPOSE: To compare the outcomes obtained with models of asymmetric and non-asymmetric intracorneal ring segments (ICRS) in keratoconic eyes with asymmetric topo-graphic patterns. METHODS: In this prospective observational study, ICRS were implanted alternately in patients with the same tomographic patterns of keratoconus assigned to four groups. Patients with the "duck" phenotype received one asymmetric or non-asymmetric ICRS and patients with the "snowman" pheno-type received two asymmetric or non-asymmetric ICRS. Visual, refractive, astigmatism, keratometric, and corneal aberrometry changes were evaluated over a 6-month follow-up period. RESULTS: Sixty-eight eyes were analyzed. No significant difference was observed between the use of one asymmetric and one non-asymmetric ICRS in duck phenotypes. In snowman keratoconus, the inferior-superior index decreased significantly (P = .03) with asymmetric but not with non-asymmetric ICRS implantation. Total corneal higher order aberrations and coma rates were lower, but not significantly so, after the implantation of two asymmetric ICRS in snowman phenotypes (2.85 ± 0.89 to 2.60 ± 0.91 µm, P = .20 and 2.64 ± 0.93 to 2.39 ± 0.98 µm, P = .21), and significantly higher after the implantation of two non-asymmetric ICRS (2.56 ± 1.28 to 3.08 ± 1.62 µm, P = .02 and 2.34 ± 1.27 to 2.84 ± 1.62 µm, P = .02). CONCLUSIONS: Asymmetric ICRS did not improve the outcomes of ICRS implantation in duck keratoconus. However, the implantation of two asymmetric ICRS was more effective than that of two non-asymmetric ICRS for decreasing vertical asymmetry and preventing increases in corneal aberration in the snowman phenotype of keratoconus. [J Refract Surg. 2021;37(8):552-561.].


Assuntos
Ceratocone , Substância Própria/diagnóstico por imagem , Substância Própria/cirurgia , Topografia da Córnea , Humanos , Ceratocone/cirurgia , Próteses e Implantes , Implantação de Prótese , Refração Ocular , Estudos Retrospectivos , Acuidade Visual
12.
J Refract Surg ; 37(8): 562-569, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34388071

RESUMO

PURPOSE: To compare 1-year visual and tomographic outcomes of topography-guided photorefractive keratectomy (TGPRK) and topography-assisted phototherapeutic keratectomy (TPTK) with corneal cross-linking (CXL). METHODS: TGPRK and TPTK were performed in 72 eyes (68 patients) and 74 eyes (71 patients), respectively. Based on the TGPRK ablation plan, the eyes underwent TPTK where the theoretical minimum corneal thickness (MCT) after surgery was less than 400 µm. In the TGPRK group, the theoretical maximum ablation depth was 50 µm after epithelium removal. In TPTK, a decentered single-step PTK was performed only in the steepest anterior curvature zone and the stromal ablation depth was limited to 25 µm. After ablation, accelerated CXL was performed in the central 8-mm zone (9 mW/cm2 for 10 minutes in "epithelium-off" mode) in both TGPRK and TPTK. The visual acuity and tomography were assessed. RESULTS: Improvement in uncorrected (P = .73) and corrected (P = .66) distance visual acuity was similar between the two groups. However, TGPRK eyes had a greater decrease in keratometry, anterior defocus, and spherical aberration (P < .001) at the cost of greater ablation of tissue (P < .001). The median MCT decreased by 27 and 52.5 µm in the TPTK and TGPRK eyes, respectively. Both groups had similar decreases in anterior root mean square of lower (P = .10) and higher (P = .12) order aberrations. CONCLUSIONS: Both TGPRK and TPTK improved visual acuity in the keratoconic eyes at 1 year of follow-up. However, TPTK removed less volume of tissue. Further, it could be an alternative to TGPRK if the theoretical stromal ablation exceeds 50 µm in thin keratoconic corneas. [J Refract Surg. 2021;37(8):562-569.].


Assuntos
Ceratocone , Fotoquimioterapia , Ceratectomia Fotorrefrativa , Substância Própria/cirurgia , Topografia da Córnea , Reagentes para Ligações Cruzadas/uso terapêutico , Humanos , Ceratocone/tratamento farmacológico , Ceratocone/cirurgia , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Prospectivos , Riboflavina/uso terapêutico , Raios Ultravioleta
13.
Exp Eye Res ; 210: 108722, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34370978

RESUMO

Keratoconus (KC), a progressive, degenerative corneal disease, represents the second leading indication for corneal transplantation globally. We have previously demonstrated that components of the Integrated Stress Response (ISR) are upregulated in human keratoconic donor tissue, and treatment of normal tissue with ISR agonists attenuates collagen production. With no consistently accepted animal models available for translational KC research, we sought to establish an in vivo model based on ISR activation to elucidate its role in the development of the KC phenotype. Four-week-old female SD rats were treated with topical SAL003 formulated as a nanosuspension or vehicle every 48 h for four doses. Animals were subject to monitoring for ocular inflammation and discomfort before being euthanized at 1, 14, or 28 days after treatment was withdrawn. Schirmer's tear test, intraocular pressure, and body weight measurements were obtained at baseline and prior to euthanasia. Globes were subject to routine histopathology, immunohistochemistry for ATF4, and qPCR for Col1a1 expression. ANOVAs and Student's t tests were used to assess statistical significance (α = 0.05). SAL003 treatment did not produce any adverse ocular or systemic phenotype but did result in decreased keratocyte density. Col1a1 transcripts were reduced, corresponding to nuclear ATF4 expression within the axial cornea. In vivo topical treatment with a gel-formulated ISR agonist recapitulates key features of the activated ISR including nuclear ATF4 expression and decreased extracellular matrix (ECM) production. Exogenous ISR agonists may present one approach to establishing a rodent model for keratoconus, a charge essential for future evaluations of pathogenesis and therapeutic interventions.


Assuntos
Cinamatos/farmacologia , Córnea/efeitos dos fármacos , Modelos Animais de Doenças , Ceratocone/induzido quimicamente , Tioureia/análogos & derivados , Fator 4 Ativador da Transcrição/metabolismo , Animais , Colágeno Tipo I/metabolismo , Córnea/metabolismo , Córnea/patologia , Ceratócitos da Córnea/patologia , Proteínas da Matriz Extracelular/metabolismo , Feminino , Ceratocone/metabolismo , Ceratocone/patologia , Ratos , Ratos Sprague-Dawley , Tioureia/farmacologia
14.
Invest Ophthalmol Vis Sci ; 62(10): 30, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34431975

RESUMO

Purpose: To elucidate dysregulated proteins in keratoconus (KC) to provide a better understanding of the molecular mechanisms that lead to the development of the disease using sequential window acquisition of all theoretical mass spectra (SWATH-MS) as a protein quantification tool of the tear proteomic profile. Methods: Prospective cross-sectional study that includes 25 keratoconic eyes and 25 healthy eyes. All participants underwent a clinical, tomographic, and aberrometric exam. Tear sample was collected using Schirmer strips and analyzed by liquid chromatography with tandem mass spectrometry. SWATH-MS was used as a quantification tool of the tear proteomic profile. The expression of the quantified proteins was compared between groups, and the biological and molecular functions of the dysregulated proteins as well as their functional relationships were studied by in silico analysis. Results: A total of 203 proteins were quantified in tear samples of patients with KC and control participants, of which 18 showed differential expression between groups (P < 0.05). An increase in the expression of 7 proteins and a decrease in the expression of 11 proteins were observed. Protein-protein interactions and gene ontology analysis showed the involvement of these dysregulated proteins in structural, inflammatory-immune, iron homeostasis, oxidative stress, and extracellular matrix proteolysis processes. Conclusions: Tear protein quantification has revealed the dysregulation of proteins involved in biological processes previously associated with KC. Among them, iron homeostasis should be highlighted as a relevant pathway in the KC pathophysiology, and it should be taken into account in the development of therapeutic targets to cope with tissue damage derived from iron accumulation and toxicity.


Assuntos
Proteínas do Olho/metabolismo , Ceratocone/metabolismo , Proteômica/instrumentação , Espectrometria de Massas em Tandem/métodos , Lágrimas/química , Adulto , Biomarcadores/análise , Cromatografia Líquida , Estudos Transversais , Feminino , Humanos , Ceratocone/diagnóstico , Masculino , Estudos Prospectivos , Proteômica/métodos
15.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(8): 438-441, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34340783

RESUMO

CLINICAL CASE: A 16-year-old man presented at our institute with progressive reduction of vision acuity in both eyes. This patient presented to our corneal service with clinical and topographical features of bilateral superior keratoconus. The clinical features, topographical, Scheimpflug and photographs images findings of a asymmetric bilateral superior keratoconus are presented.


Assuntos
Ceratocone , Adolescente , Córnea , Topografia da Córnea , Humanos , Ceratocone/diagnóstico , Masculino , Acuidade Visual
16.
Eye Contact Lens ; 47(9): 511-514, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424224

RESUMO

PURPOSE: To characterize very asymmetric keratoconus (KC) in terms of clinical demographics and risk factors in the Japanese population. METHODS: We retrospectively reviewed the clinical records of patients with very asymmetric KC attending a university hospital. Patients with very asymmetric KC had defined clinical KC in one eye and normal topography in the fellow eye. All patients completed a questionnaire on potential risk factors (family history of KC, atopy, asthma, allergy, heart disease, sleep apnea, Down syndrome, eye rubbing, prone sleep position, and dominant hand). These data were compared with those of patients with clinical or topographic KC in both eyes. Subgroup analysis of very asymmetric KC eyes were performed based on the KC status: mild and severe. RESULTS: We retrospectively investigated 66 patients with very asymmetric KC and 505 patients with KC. Patients reported eye rubbing (53%-56%), allergy (62%-63%), and atopy (28%-29%) in both groups. There was no significant difference in terms of risk factors between the two groups. Approximately half of the 66 patients with very asymmetric KC had KC eyes ipsilateral to the dominant hand. Subgroup analysis of very asymmetric KC showed that atopy and asthma were more frequent in the mild KC group than in the severe KC group. Forty-four of 60 patients (73.3%) were using corneal, rigid, gas-permeable contact lenses (corneal GPs) for the KC eye, of which 30 patients (68.2%) were also using a corneal GP for the fellow eye. CONCLUSIONS: The patient-reported frequency of eye rubbing, allergy, and atopy were similar between KC and very asymmetric KC. Furthermore, we found no association between hand dominance and KC laterality.


Assuntos
Ceratocone , Córnea , Topografia da Córnea , Humanos , Ceratocone/epidemiologia , Ceratocone/etiologia , Estudos Retrospectivos , Fatores de Risco
17.
Eye Contact Lens ; 47(9): 515-519, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424225

RESUMO

OBJECTIVES: To assess dry eye symptoms associated with different contact lens modalities in patients with keratoconus using a dry eye questionnaire. METHODS: An online survey was distributed by the National Keratoconus Foundation. The survey asked participants to report demographic characteristics, current optical correction, age at the time of diagnosis of keratoconus, and contact lens history. The 12-item Ocular Surface Disease Index (OSDI) questionnaire was also completed. Data from participants wearing the same contact lens modality bilaterally were analyzed. RESULTS: The survey was completed by 197 individuals wearing the same contact lens modality bilaterally. The average age of participants at the time of the survey was 47.2±14.8 years (range: 15-87 years), and the average age at which keratoconus was diagnosed was 26.1±9.9 years (range: 8-55 years). The mean overall OSDI score of all participants was 40.2±22.8 (range: 0-100). There was no difference in the mean OSDI scores based on current contact lens modality type (F=1.79; n=187; P=0.13). Based on an OSDI score of 33 or higher, 90% of participants reported symptoms indicative of dry eye disease. Scleral lens wearers reported less discomfort on the individual items related to windy and low-humidity conditions. CONCLUSIONS: Individuals with keratoconus, irrespective of contact lens modality, report a high incidence of dry eye symptoms.


Assuntos
Lentes de Contato , Síndromes do Olho Seco , Ceratocone , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lentes de Contato/efeitos adversos , Síndromes do Olho Seco/epidemiologia , Síndromes do Olho Seco/etiologia , Humanos , Ceratocone/terapia , Pessoa de Meia-Idade , Esclera , Inquéritos e Questionários , Adulto Jovem
18.
Eye Contact Lens ; 47(9): 526-532, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424226

RESUMO

OBJECTIVE: To evaluate the content, quality, and reliability of keratoconus-related YouTube videos as sources for patient education. METHODS: YouTube was queried using the keywords "keratoconus," "contact lenses for keratoconus," "corneal cross-linking," and "corneal transplant surgery for keratoconus." Two ophthalmologists independently classified videos as useful, misleading, or patient testimonials and rated them using the DISCERN score (range, 16-75), Journal of the American Medical Association score (JAMAS; range, 0-4), Global Quality Score (GQS; range, 1-5), and Keratoconus-Specific Score (KSS; range, 0-32). Interrater agreement was analyzed using intraclass correlation coefficients. Multivariate linear regression models were fitted to identify factors associated with quality and popularity indices. RESULTS: Of the 300 videos screened, 201 were included in the study, 58% were classified as useful, 13% as misleading, and 29% as patient views. Overall video quality was poor, with an average DISCERN score of 22, JAMAS of 1.2, GQS of 1.8, and KSS of 4.5. Misleading videos scored significantly lower than average but had higher popularity compared with useful videos. Video length inversely correlated with popularity index. Television shows were more likely to share misleading information than other uploaders, whereas all videos uploaded by university channels provided useful information but constituted only 12% of all videos. CONCLUSIONS: Videos rated the best source of information were not the ones most popular. YouTube has great potential to change the attitude of individuals both for and against the right choice. Therefore, health professionals should act to use this potential in favor of effective and reliable health communication.


Assuntos
Ceratocone , Mídias Sociais , Humanos , Ceratocone/terapia , Educação de Pacientes como Assunto , Reprodutibilidade dos Testes , Estados Unidos
19.
Transl Vis Sci Technol ; 10(9): 15, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34388236

RESUMO

Purpose: To theoretically compare corneal displacement and the von Mises (VM) stress distribution of deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) for keratoconus (KC) and to evaluate the effects of residual stromal thickness (RST) and intraocular pressure (IOP) on postoperative corneal biomechanics. Methods: We performed DALK and PK simulations using Ansys by employing anisotropic nonlinear hyperelastic corneal material properties. We analyzed corneal displacement and VM stress in DALK and PK models under IOPs of 10, 15, 20, and 25 mmHg. We established two DALK models: The ideal-type DALK ensured that postoperative central corneal thickness was constant at 560 µm and the corneal graft thickness varied with RST. The clinical-type DALK ensured that corneal grafts had the same thickness (500 µm) regardless of RST. Then we analyzed the effects of RST and IOP on postoperative corneal displacement and VM stress. Results: Corneal displacement and VM stress were lower in the DALK than in the PK model. In the ideal-type DALK model, an increase in RST was associated with increased deformation and decreased VM stress in the healing zone, except for a RST of 0 µm. In the clinical-type DALK model, deformation and VM stress in the healing zone decreased with an increase in RST, except for a RST of 0 µm. Conclusions: DALK showed more stability than PK. For the ideal-type DALK model, an increase in RST resulted in decreased postoperative corneal biomechanics in the healing zone. For the clinical-type DALK model, corneal deformation and VM stress decreased with an increase in RST, which provides numerical evidence for the design of corneal transplantation for patients with KC. Translational Relevance: In this computational modeling study, we first theoretically compared corneal biomechanics between DALK and PK for KC. Then, the effects of RST and IOP on postoperative corneal biomechanics were investigated. Our findings provide novel insights into the optimal design for corneal transplantation for patients with KC.


Assuntos
Transplante de Córnea , Ceratocone , Córnea/cirurgia , Análise de Elementos Finitos , Humanos , Ceratocone/cirurgia , Ceratoplastia Penetrante/efeitos adversos
20.
Transl Vis Sci Technol ; 10(9): 32, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34436543

RESUMO

Purpose: To enhance the current standards of subclinical keratoconus screening based on the statistical modeling of the pixel intensity distribution of Scheimpflug images. Methods: Scheimpflug corneal tomographies corresponding to 25 corneal meridians of 60 participants were retrospectively collected and divided into three groups: controls (20 eyes), subclinical keratoconus (20 eyes), and clinical keratoconus (20 eyes). Only right eyes were selected. After corneal segmentation, pixel intensities of the stromal tissue were statistically modeled using a Weibull probability density function from which parameter α (pixel brightness) was derived. Further, data were transformed to polar coordinates, smoothed, and interpolated to build a map of the corneal α parameter. The discriminative power of the method was analyzed using receiver operating characteristic curves. Results: The proposed platform-independent method achieved a higher performance in discriminating subclinical keratoconus from control eyes (90.0% sensitivity, 95.0% specificity, 0.97 area under the curve [AUC]) than the standard method (Belin-Ambrósio enhanced ectasia display), which uses only corneal morphometry (85.0% sensitivity, 85.0% specificity, 0.80 AUC). Conclusions: Analysis of light backscatter at the cornea successfully discriminates subclinical keratoconus from control eyes, upgrading the results previously reported in the literature. Translational Relevance: The proposed methodology has the potential to support clinicians in the detection of keratoconus before showing clinical signs.


Assuntos
Ceratocone , Córnea/diagnóstico por imagem , Paquimetria Corneana , Topografia da Córnea , Densitometria , Humanos , Ceratocone/diagnóstico , Estudos Retrospectivos , Sensibilidade e Especificidade
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