RESUMO
PURPOSE: To compare corneal haze between active ulcer and healed scarring using a Scheimpflug densitometry. MATERIALS AND METHODS: A prospective longitudinal study enrolled 30 patients (30 eyes) with ulcerative keratitis (UK). Each subject's corneal optical density (COD) was measured with a Scheimpflug corneal densitometry, Pentacam® AXL (Oculus GmbH, Wetzlar, Germany), at the active ulcerative and complete scarring stage. The COD data were analyzed through distinct methods (inbuilt, sorted annular partitions, and ulcer-matching densitometric maps). We compared different CODs to select the better index for clinically monitoring the transition from corneal ulceration to healed scar. RESULTS: The CODs of the periphery (P = 0.0024) and outside of the active ulcer (P = 0.0002) significantly decreased after scarring. Partitioning the cornea into different depths and annular zones, the anterior layer, center layer, and the 2-6 mm annular zone had a more remarkable COD decrease after scar formation. The 3rd-sorted COD in the anterior layer revealed the highest area under the receiver-operating characteristic curves (0.709), in which 90% of subjects had COD reduction during the ulcer-to-scar transition. CONCLUSIONS: Aside from subjective judgment based on clinical signs, the Scheimpflug tomography-based densitometry could provide objective and efficient monitoring of the corneal opacity evolution in UK patients. Because the 3rd-sorted annular COD is a better index than the inbuilt or mapping CODs in differentiating active ulcers from healed scars, this COD could be a clinically promising parameter to monitor the progression of UK patients.
Assuntos
Córnea , Úlcera da Córnea , Densitometria , Humanos , Estudos Prospectivos , Feminino , Masculino , Densitometria/métodos , Pessoa de Meia-Idade , Úlcera da Córnea/diagnóstico , Córnea/patologia , Córnea/diagnóstico por imagem , Seguimentos , Adulto , Cicatrização , Cicatriz/diagnóstico , Cicatriz/etiologia , Idoso , Curva ROC , Acuidade Visual , Topografia da Córnea/métodos , Opacidade da Córnea/diagnóstico , Opacidade da Córnea/etiologia , Opacidade da Córnea/fisiopatologiaRESUMO
Excimer lasers induces significant changes to corneal structure and corneal biomechanics. The aim of this paper is to describe all laser-tissue interactions which are relevant for clinical practice, particularly, we will focus on laser ablations profiles, causes of regression and haze and prevention of those. At last the manuscript will describe the impact on corneal biomechanics of different Laser Vision Corrections techniques.
Assuntos
Córnea/fisiopatologia , Opacidade da Córnea/cirurgia , Lasers de Excimer/uso terapêutico , Ceratectomia Fotorrefrativa , Fenômenos Biomecânicos , Córnea/diagnóstico por imagem , Córnea/cirurgia , Opacidade da Córnea/diagnóstico , Opacidade da Córnea/fisiopatologia , Humanos , CicatrizaçãoRESUMO
Limbal Stem Cell Deficiency (LSCD), caused due to corneal injury, primarily by chemical/alkali burns, leads to compromised vision. Recently, several animal models of corneal alkali burn injury have become available. The majority of the studies with these animal models start interventions soon after the injury. However, in the clinical setting, there is a considerable delay before the intervention is initiated. Detailed knowledge of the molecular, histopathological, and clinical parameters associated with the progression of the injury leading to LSCD is highly desirable. In this context, we set out to investigate clinical, histopathological parameters of ocular surface alkali burn over a long period of time, post-injury. Limbal stem cell-deficient animal models of rabbits were created by alkali burn using sodium hydroxide, which was then assessed for their progression towards LSCD by grading the alkali burn, corneal haze, and vascularization. Additionally, cells present on the corneal surface after the burn was investigated by histology and immunophenotyping. Grading of rabbit eyes post-alkali burn had shown complete conjunctivalization in 80% (n = 12/15) of the rabbits with the alkali burn grade score of 3.88 ± 0.29 in three months and remained stable at four months (4.12 ± 0.24). However, ocular surface showed self-healing in 20% (n = 3/15) of the rabbits with a score of 1.67 ± 0.34 in four months irrespective of similar alkali injury. These self-healing corneas exhibited decreased opacity score from 2.51 ± 0.39 to 0.66 ± 0.22 (p = 0.002) and regressed vascularity from 1.66 ± 0.41 to 0.66 ± 0.33 in one to nine months, respectively. Restoration of the corneal phenotype (CK3+) was observed in central and mid-peripheral regions of the self-healing corneas, and histology revealed the localization of inflammatory cells to the peripheral cornea when compared to conjunctivalized and scarred LSCD eyes. Our study shows the essentiality to consider the time required for surgical intervention after the corneal alkali injury in rabbit models as evident from their tendency to self-heal and restore corneal phenotype without therapy. Such information on the possibility of self-healing should be useful in further studies as well as determining interventional timings and strategy during clinical presentation of corneal alkali burns.
Assuntos
Queimaduras Químicas/fisiopatologia , Lesões da Córnea/fisiopatologia , Neovascularização da Córnea/fisiopatologia , Opacidade da Córnea/fisiopatologia , Queimaduras Oculares/induzido quimicamente , Recuperação de Função Fisiológica/fisiologia , Hidróxido de Sódio/toxicidade , Animais , Cáusticos/toxicidade , Túnica Conjuntiva/fisiopatologia , Córnea/fisiopatologia , Modelos Animais de Doenças , Queimaduras Oculares/fisiopatologia , Seguimentos , Limbo da Córnea/citologia , Coelhos , Transplante de Células-Tronco , Cicatrização/fisiologiaRESUMO
The lens and central cornea are avascular. It was assumed that the adult lens had no source of immune cells and that the basement membrane capsule surrounding the lens was a barrier to immune cell migration. Yet, microfibril-associated protein-1 (MAGP1)-rich ciliary zonules that originate from the vasculature-rich ciliary body and extend along the surface of the lens capsule, form a potential conduit for immune cells to the lens. In response to cornea debridement wounding, we find increased expression of MAGP1 throughout the central corneal stroma. The immune cells that populate this typically avascular region after wounding closely associate with this MAGP1-rich matrix. These results suggest that MAGP1-rich microfibrils support immune cell migration post-injury. Using this cornea wound model, we investigated whether there is an immune response to the lens following cornea injury involving the lens-associated MAGP1-rich ciliary zonules. Our results provide the first evidence that following corneal wounding immune cells are activated to travel along zonule fibers that extend anteriorly along the equatorial surface of the lens, from where they migrate across the anterior lens capsule. These results demonstrate that lens-associated ciliary zonules are directly involved in the lens immune response and suggest the ciliary body as a source of immune cells to the avascular lens.
Assuntos
Corpo Ciliar/imunologia , Lesões da Córnea/fisiopatologia , Opacidade da Córnea/fisiopatologia , Imunidade/imunologia , Cristalino/imunologia , Microfibrilas/imunologia , Proteínas dos Microfilamentos/metabolismo , Animais , Córnea/cirurgia , Lesões da Córnea/etiologia , Lesões da Córnea/metabolismo , Opacidade da Córnea/etiologia , Opacidade da Córnea/metabolismo , Substância Própria/imunologia , Citoesqueleto , Cristalino/metabolismo , Cristalino/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Winchester syndrome (WS, MIM #277950) is an extremely rare autosomal recessive skeletal dysplasia characterized by progressive joint destruction and osteolysis. To date, only one missense mutation in MMP14, encoding the membrane-bound matrix metalloprotease 14, has been reported in WS patients. Here, we report a novel hypomorphic MMP14 p.Arg111His (R111H) allele, associated with a mitigated form of WS. Functional analysis demonstrated that this mutation, in contrast to previously reported human and murine MMP14 mutations, does not affect MMP14's transport to the cell membrane. Instead, it partially impairs MMP14's proteolytic activity. This residual activity likely accounts for the mitigated phenotype observed in our patients. Based on our observations as well as previously published data, we hypothesize that MMP14's catalytic activity is the prime determinant of disease severity. Given the limitations of our in vitro assays in addressing the consequences of MMP14 dysfunction, we generated a novel mmp14a/b knockout zebrafish model. The fish accurately reflected key aspects of the WS phenotype including craniofacial malformations, kyphosis, short-stature and reduced bone density owing to defective collagen remodeling. Notably, the zebrafish model will be a valuable tool for developing novel therapeutic approaches to a devastating bone disorder.
Assuntos
Anormalidades Múltiplas/genética , Contratura/genética , Opacidade da Córnea/genética , Anormalidades Craniofaciais/genética , Transtornos do Crescimento/genética , Metaloproteinase 14 da Matriz/genética , Osteólise/genética , Osteoporose/genética , Anormalidades Múltiplas/fisiopatologia , Alelos , Animais , Domínio Catalítico/genética , Contratura/fisiopatologia , Opacidade da Córnea/fisiopatologia , Anormalidades Craniofaciais/fisiopatologia , Técnicas de Inativação de Genes , Transtornos do Crescimento/fisiopatologia , Humanos , Camundongos , Osteólise/fisiopatologia , Osteoporose/fisiopatologia , Fenótipo , Peixe-ZebraRESUMO
PURPOSE: To determine the incidence of spontaneous regression of congenital corneal opacity (CCO) and identify clinical factors associated with the regression. METHODS: Medical records and anterior segment photographs were reviewed of 57 eyes in 35 patients with CCO that were not related to congenital glaucoma, tumors, infection, trauma, or metabolic disorders and were followed up without corneal transplantation for longer than one year at Seoul National University Hospital. Spontaneous regression of corneal opacity was defined as a decrease in corneal opacity significant enough for visual axis clearance. Data on demographics, systemic, and ocular characteristics were collected and compared between patients who had spontaneous regression of CCO and those who did not. RESULTS: Spontaneous regression of corneal opacity developed in 32 eyes (22 patients, 56.1%) out of 57 CCO eyes (35 patients) at the mean 8.2 ± 5.4 months of age (the median 6.7 months). Absence of combined ocular anomalies such as iris anomaly, lens opacity, and peripheral corneal vascularization was significantly associated with the regression of opacity. CONCLUSIONS: Corneal opacity can spontaneously regress in 56.1% of eyes with CCO during the first year of life. Careful follow-up with amblyopia management can be one of treatment options for CCO.
Assuntos
Córnea/diagnóstico por imagem , Opacidade da Córnea/diagnóstico , Refração Ocular/fisiologia , Acuidade Visual , Adulto , Idoso , Idoso de 80 Anos ou mais , Opacidade da Córnea/congênito , Opacidade da Córnea/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Microscopia Acústica , Pessoa de Meia-Idade , Remissão Espontânea , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: To report three cases of congenital corneal opacity where intraocular pressure (IOP) readings were high despite the use of multiple anti-glaucoma eye drops and normalized after corneal transplantation. CASE PRESENTATION: Three Korean infants presented with bilateral dense stromal opacification which had been present since birth. IOPs measured by rebound tonometer were high despite administration of multiple anti-glaucoma medications. One eye of each patient underwent penetrating keratoplasty (PK) because corneal opacity impaired visual development. Immediately after PK, IOPs were normalized and maintained normal without medication, whereas they remained high in the contralateral unoperated eye. On histology, stromal fibrosis was observed in the removed corneal button, and molecular assays revealed increased levels of type 1 and 5 collagens. CONCLUSION: The IOP measurement using the conventional applanation-based tonometry can be inaccurate in congenital corneal opacity which is marked by corneal fibrosis. Therefore, IOP values should be interpreted with caution in these patients, and the possibility of false-positive diagnosis of glaucoma considered.
Assuntos
Opacidade da Córnea/fisiopatologia , Pressão Intraocular/fisiologia , Tonometria Ocular/normas , Anti-Hipertensivos/uso terapêutico , Opacidade da Córnea/patologia , Opacidade da Córnea/cirurgia , Substância Própria/patologia , Feminino , Humanos , Lactente , Ceratoplastia Penetrante , MasculinoRESUMO
PURPOSE: To characterize the corneal changes in peripheral hypertrophic subepithelial corneal opacification (PHSCO) considering elevation of the anterior and posterior corneal surface, corneal astigmatism, tear secretion, and endothelial cell density. METHODS: Thirty-eight eyes of 22 patients with PHSCO on at least 1 eye and 38 eyes of 22 age- and sex-matched healthy subjects were included in this retrospective cross-sectional study. Using the Pentacam system (Oculus, Wetzlar, Germany), measurement of the anterior and posterior corneal surface was performed. In addition, the Schirmer test was conducted, and endothelial cells were counted in the central cornea with a specular microscope (SP-3000P; Topcon, Tokyo, Japan). RESULTS: The mean age was 55.2±11.7 years in patients with PHSCO and 54.1±12.4 years in healthy subjects. The corneas of patients with PHSCO showed higher corneal astigmatism of both the corneal anterior and posterior surface (2.9/0.5 vs. 0.8/0.3 D, PHSCO vs. controls, P=<0.001/<0.01). The cornea was thickest in the peripheral 12-o'clock position and the peripheral superior nasal area. Remarkably, central endothelial cell density was markedly reduced in patients with PHSCO (2,372.6 cell/mm±328.1 vs. 2,673 cells/mm±287.6, P<0.01, PHSCO vs. controls). Also, the Schirmer test revealed lower tear secretion in patients with PHSCO (9.8±4.4 mm vs. 14.3±5.7 mm, P<0.001, PHSCO vs. controls). CONCLUSION: The astigmatism of both the anterior and posterior corneal surface is increased in patients with PHSCO. Intriguingly, tear secretion and central endothelial cell density are reduced in patients with PHSCO. These measurements may become useful to assess the impact of morphological changes on vision and to track disease progression in PHSCO.
Assuntos
Astigmatismo/fisiopatologia , Opacidade da Córnea/fisiopatologia , Endotélio Corneano/patologia , Epitélio Corneano/patologia , Lágrimas/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Estudos Transversais , Feminino , Humanos , Hipertrofia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acuidade Visual/fisiologiaRESUMO
BACKGROUND: To evaluate corneal biomechanical properties by the Ocular Response Analyzer (ORA) in non keratoconic patients underwent penetrating keratoplasty (PK). METHODS: Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann- correlated intraocular pressure (IOPg), cornea-compensated IOP (IOPcc) using the ORA, and central graft thickness (CGT) were measured in 30 eyes at least two years after penetrating keratoplasty for non keratoconic indications. IOP using the Goldmann applanation tonometer (GAT) was also obtained after compensation for graft thickness and astigmatism. RESULTS: The mean age of patients was 33.1 ± 10.13 years; indications for PK were herpetic corneal scar (53.3%), corneal stromal dystrophy (23.3%), traumatic corneal opacity (10%), chemical corneal opacity (6.7%), and Fuchs endothelial dystrophy (6.7%). Mean CH and CRF were 8.52 ± 1.81 mmHg, and 8.56 ± 1.59 mmHg, respectively. Mean CGT was 532.43 ± 30 µm. Mean IOP GAT, IOPg, and IOPcc were 11.88 ± 3.66, 14.64 ± 4.08, and 17.27 ± 4.60 mmHg, respectively (P < 0.001). No significant association was found between CGT and IOP readings obtained using either the ORA or GAT. There were significant negative association between CH with both IOP GAT and IOPcc, while CRF had significant positive association with IOPg. CONCLUSION: After penetrating keratoplasty for non keratoconic patients, graft biomechanics does not return to average values even 2 years after the operation; moreover, intraocular pressure measurement with ORA gives higher values than thickness compensated GAT.
Assuntos
Córnea/fisiopatologia , Opacidade da Córnea/cirurgia , Distrofia Endotelial de Fuchs/cirurgia , Pressão Intraocular/fisiologia , Ceratoplastia Penetrante/métodos , Adulto , Idoso , Córnea/cirurgia , Opacidade da Córnea/fisiopatologia , Estudos Transversais , Elasticidade , Feminino , Seguimentos , Distrofia Endotelial de Fuchs/fisiopatologia , Humanos , Ceratocone , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Tonometria Ocular/métodos , Acuidade Visual , Adulto JovemRESUMO
OBJECTIVES: To highlight the clinical characteristics, and visual and corneal tomographic outcomes of central toxic keratopathy (CTK) after contact lens (CL) wear and mechanical debridement. METHODS: A retrospective observational case series with literature review. RESULTS: Four patients (4 eyes) were included in this study; 3 (75%) females, mean age 29.3±8.1 years. The mean follow-up was 13.5±7.5 months. Early central or paracentral stromal opacification, assuming an inverse dome-shaped pattern observed under anterior-segment optical coherence tomography, with corneal flattening (Kmean 40.4±1.3 D) and thinning (mean thinnest pachymetry=404.8±29.4 microns) were observed in all cases. All patients had a recent use of CL wear, with three after mechanical debridement for recurrent corneal erosion syndrome. None of them had any previous laser refractive surgery (LRS). The mean corrected distance visual acuity improved from 20/40 (ranged 20/25-20/50) initially to 20/30 (ranged 20/20-20/40) at final follow-up, and the outcome was not influenced by the use of topical steroids. A mean improvement of corneal flattening (+Kmean 1.2±1.2 D), thinning (+123.5±23.8 microns), and astigmatism (-3.0±2.7 D), via epithelial and stromal remodeling, was observed up to 15 months after CTK. Persisting reduced corneal sensation was noted in all patients at the final follow-up. CONCLUSIONS: Central toxic keratopathy is not an exclusive complication of LRS, and it may occur after CL wear and mechanical debridement. Our findings are similar to those of LRS-related CTK and toxic peripheral keratopathy. Awareness of the clinical associations and understanding of the clinical course and tomographic characteristics of CTK helps obviate unnecessary investigation and overtreatment. Further studies are required to elucidate the underlying pathogenesis of this rare clinical entity.
Assuntos
Lentes de Contato Hidrofílicas/efeitos adversos , Opacidade da Córnea/etiologia , Substância Própria/patologia , Desbridamento , Acuidade Visual/fisiologia , Adulto , Opacidade da Córnea/fisiopatologia , Opacidade da Córnea/cirurgia , Paquimetria Corneana , Substância Própria/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Microscopia com Lâmpada de Fenda , Tomografia de Coerência Óptica , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia , Transtornos da Visão/cirurgia , Adulto JovemRESUMO
PURPOSE: Optical iridectomy creates a defect in the iris to allow an alternative clear visual axis in cases of central corneal opacities occluding the pupillary axis. The purpose of this study is to evaluate the outcomes of optical sector iridectomy in children with Peters anomaly. METHODS: Retrospective case series. The medical records of all patients diagnosed with Peters anomaly who underwent optical iridectomy during the years 2002-2014 were reviewed. Data collection included surgical and visual acuity outcomes. RESULTS: Twenty-nine eyes (22 patients) were included in the study. Mean age at the time of surgery was 15.6 ± 26.3 months. Eighteen (81.8%) patients had bilateral disease. No intraoperative complications occurred. A red reflex was obtained in 28 (96.6%) eyes after surgery. Mean visual acuity improved from 2.5 ± 0.3 to 1.8 ± 0.6 in logMAR (p < 0.001). Vision improved in 21 (72.4%) eyes, remained stable in 5 (17.2%) eyes, and deteriorated in 3 (10.3%) eyes. Postoperatively visual acuity improved significantly in the patients with the bilateral disease (p < 0.05), but not in the unilateral group (p = 0.056). Mean follow-up time was 41.6 ± 43.8 months. During the follow-up period, five (17.2%) eyes were diagnosed with glaucoma, two (6.9%) eyes underwent PK, one (3.4%) eye underwent an additional sector iridectomy, and one (3.4%) eye underwent keratoprosthesis. CONCLUSIONS: In this largest series published of optical iridectomy for Peters anomaly, it was found to be a safe procedure. Improvement in visual acuity is expected, particularly in bilateral cases. The utility of optical iridectomy in unilateral cases necessitates further studies.
Assuntos
Segmento Anterior do Olho/anormalidades , Opacidade da Córnea/cirurgia , Anormalidades do Olho/cirurgia , Iridectomia/métodos , Iris/cirurgia , Acuidade Visual , Segmento Anterior do Olho/fisiopatologia , Segmento Anterior do Olho/cirurgia , Pré-Escolar , Opacidade da Córnea/fisiopatologia , Anormalidades do Olho/fisiopatologia , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Resultado do TratamentoRESUMO
PURPOSE: To report a case of wavelike interface opacities in a patient who underwent Descemet-stripping automated endothelial keratoplasty (DSAEK) and was managed conservatively over the course of 7 years. METHODS: A 65-year-old woman underwent DSAEK for pseudophakic bullous keratopathy. Textural wavelike opacities were noted in the graft-host interface 6 days postoperatively without evidence of anterior segment inflammation. The patient's vision was also initially limited by the presence of cystoid macular edema (CME). Six months postoperatively, CME had resolved but the patient's vision failed to improve better than 20/80 because of the persistent dense interface opacities. The patient refused to undergo graft exchange despite a suboptimal visual result and she therefore was observed over time. RESULTS: The interface opacities started to regress and her visual acuity improved to 20/30 by 9 months postoperatively. The opacities became gradually less prominent over the next few years, and at 7 years postoperatively, her best-corrected vision was 20/25. CONCLUSION: In this case, observation of this post-DSAEK complication rather than surgical intervention resulted in a favorable long-term visual outcome.
Assuntos
Opacidade da Córnea/etiologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/efeitos adversos , Transtornos da Visão/etiologia , Idoso , Opacidade da Córnea/fisiopatologia , Opacidade da Córnea/terapia , Feminino , Seguimentos , Humanos , Transtornos da Visão/fisiopatologia , Transtornos da Visão/terapia , Acuidade Visual/fisiologiaAssuntos
Segmento Anterior do Olho/anormalidades , Opacidade da Córnea/fisiopatologia , Substância Própria/fisiopatologia , Lâmina Limitante Posterior/fisiopatologia , Anormalidades do Olho/fisiopatologia , Adolescente , Segmento Anterior do Olho/diagnóstico por imagem , Segmento Anterior do Olho/fisiopatologia , Opacidade da Córnea/diagnóstico por imagem , Substância Própria/diagnóstico por imagem , Lâmina Limitante Posterior/diagnóstico por imagem , Anormalidades do Olho/diagnóstico por imagem , Feminino , Seguimentos , Glaucoma/diagnóstico , Glaucoma/fisiopatologia , Glaucoma/cirurgia , Humanos , Pressão Intraocular/fisiologia , Microscopia Acústica , TrabeculectomiaRESUMO
The corneal wound healing response, including the development of stromal opacity in some eyes, is a process that often leads to scarring that occurs after injury, surgery or infection to the cornea. Immediately after epithelial and stromal injury, a complex sequence of processes contributes to wound repair and regeneration of normal corneal structure and function. In some corneas, however, often depending on the type and extent of injury, the response may also lead to the development of mature vimentin+ α-smooth muscle actin+ desmin+ myofibroblasts. Myofibroblasts are specialized fibroblastic cells generated in the cornea from keratocyte-derived or bone marrow-derived precursor cells. The disorganized extracellular matrix components secreted by myofibroblasts, in addition to decreased expression of corneal crystallins in these cells, are central biological processes that result in corneal stromal fibrosis associated with opacity or "haze". Several factors are associated with myofibroblast generation and haze development after PRK surgery in rabbits, a reproducible model of scarring, including the amount of tissue ablated, which may relate to the extent of keratocyte apoptosis in the early response to injury, irregularity of stromal surface after surgery, and changes in corneal stromal proteoglycans, but normal regeneration of the epithelial basement membrane (EBM) appears to be a critical factor determining whether a cornea heals with relative transparency or vision-limiting stromal opacity. Structural and functional abnormalities of the regenerated EBM facilitate prolonged entry of epithelium-derived growth factors such as transforming growth factor ß (TGF-ß) and platelet-derived growth factor (PDGF) into the stroma that both drive development of mature myofibroblasts from precursor cells and lead to persistence of the cells in the anterior stroma. A major discovery that has contributed to our understanding of haze development is that keratocytes and corneal fibroblasts produce critical EBM components, such as nidogen-1, nidogen-2 and perlecan, that are essential for complete regeneration of a normal EBM once laminin secreted by epithelial cells self-polymerizes into a nascent EBM. Mature myofibroblasts that become established in the anterior stroma are a barrier to keratocyte/corneal fibroblast contributions to the nascent EBM. These myofibroblasts, and the opacity they produce, often persist for months or years after the injury. Transparency is subsequently restored when the EBM is completely regenerated, myofibroblasts are deprived of TGFß and undergo apoptosis, and the keratocytes re-occupy the anterior stroma and reabsorb disordered extracellular matrix. The aim of this review is to highlight factors involved in the generation of stromal haze and its subsequent removal.
Assuntos
Lesões da Córnea/patologia , Opacidade da Córnea/patologia , Substância Própria/patologia , Epitélio Corneano/patologia , Animais , Apoptose/fisiologia , Membrana Basal/patologia , Lesões da Córnea/metabolismo , Ceratócitos da Córnea/metabolismo , Opacidade da Córnea/metabolismo , Opacidade da Córnea/fisiopatologia , Proteínas da Matriz Extracelular/metabolismo , Humanos , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Cicatrização/fisiologiaRESUMO
Anophthalmia and microphthalmia are the most severe malformations of the eye, referring to a congenital absence, and a reduced size of the eyeball respectively. More than 20 genes have been shown to be mutated in patients with syndromic and non-syndromic forms of anophthalmia-microphthalmia. In a recent study combining autozygome and exome analysis, a homozygous loss of function mutation in TENM3 (previously named ODZ3) was reported in two siblings with isolated bilateral colobomatous microphthalmia from a consanguineous Saudi family. Herein, we report a third patient (not related to the previously reported family) with bilateral colobomatous microphthalmia and developmental delay in whom genetic studies identified a homozygous TENM3 splicing mutation c.2968-2A>T (p.Val990Cysfs*13). This report supports the association of TENM3 mutations with colobomatous microphthalmia and expands the phenotypic spectrum associated with mutations in this gene. © 2016 Wiley Periodicals, Inc.
Assuntos
Encefalopatias Metabólicas Congênitas/genética , Coloboma/genética , Opacidade da Córnea/genética , Deficiências do Desenvolvimento/genética , Predisposição Genética para Doença , Deficiência Intelectual/genética , Proteínas de Membrana/genética , Microcefalia/genética , Microftalmia/genética , Proteínas do Tecido Nervoso/genética , Processamento Alternativo/genética , Encefalopatias Metabólicas Congênitas/fisiopatologia , Criança , Coloboma/fisiopatologia , Opacidade da Córnea/fisiopatologia , Deficiências do Desenvolvimento/fisiopatologia , Homozigoto , Humanos , Deficiência Intelectual/fisiopatologia , Masculino , Microcefalia/fisiopatologia , Microftalmia/fisiopatologia , MutaçãoRESUMO
Bosma arhinia microphthalmia syndrome (Bosma syndrome)(OMIM 603457) is a congenital condition characterized by microphthalmia with coloboma, arhinia and endocrine findings in the setting of normal intelligence and brain structure. This condition is quite rare with fewer than 50 case reports and series. Although pathogenesis is presumed to be genetic, the cause remains unknown. We report an individual with Bosma syndrome who had bilateral colobomatous microphthalmia, arhinia, high arched palate, mild ear malformations, and hypogonadotropic hypogonadism requiring growth hormone treatment in childhood, and normal intelligence. Clinical evaluation was significant for a geometrically abnormal aorta with effacement of the sinotubular ridge, a finding not previously reported in this condition. An MRI revealed absent olfactory bulbs. Suggested criteria for diagnosis of Bosma should include arhinia, hypoplastic maxilla, normal cognition, and hypogonadotropic hypogonadism in males.
Assuntos
Anormalidades Múltiplas/fisiopatologia , Atresia das Cóanas/fisiopatologia , Coloboma/fisiopatologia , Microftalmia/fisiopatologia , Nariz/anormalidades , Anormalidades Múltiplas/genética , Adulto , Encefalopatias Metabólicas Congênitas/diagnóstico por imagem , Encefalopatias Metabólicas Congênitas/genética , Encefalopatias Metabólicas Congênitas/fisiopatologia , Atresia das Cóanas/diagnóstico por imagem , Atresia das Cóanas/genética , Coloboma/diagnóstico por imagem , Coloboma/genética , Opacidade da Córnea/diagnóstico por imagem , Opacidade da Córnea/genética , Opacidade da Córnea/fisiopatologia , Ossos Faciais/anormalidades , Ossos Faciais/diagnóstico por imagem , Ossos Faciais/patologia , Humanos , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/genética , Deficiência Intelectual/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Microcefalia/diagnóstico por imagem , Microcefalia/genética , Microcefalia/fisiopatologia , Microftalmia/diagnóstico por imagem , Microftalmia/genética , Nariz/diagnóstico por imagem , Nariz/fisiopatologia , Bulbo Olfatório/diagnóstico por imagem , Bulbo Olfatório/patologiaRESUMO
The human cornea is rich in extracellular matrix. The stroma constitutes the main thickness of the cornea, which consists of collagens and proteoglycans mainly. The epithelial-stromal and stromal dystrophies of the cornea are either autosomal dominant or recessive inherited disorders, which are unrelated to inflammation or trauma. The diseases can manifest in each layer of the cornea, but in most cases the corneal stroma is affected. Generally, they develop in childhood or young adulthood but the diagnosis is only possible when clinical signs (epithelial erosions, decreased visual acuity, photophobia) develop. The different protein aggregates (hyaline, amyloid, crystalline) deposited in the corneal layers result in mild or advanced corneal opacity and loss of the corneal transparency due to disorganisation of the extracellular matrix. In some of the corneal dystrophies the keratane sulphate proteoglycan looses its function which results in a loss of the regular interfibrillar spacing. Due to the severe corneal opacity patients may need corneal transplantation. Orv. Hetil., 2016, 157(33), 1299-1303.
Assuntos
Córnea/patologia , Distrofias Hereditárias da Córnea/diagnóstico , Distrofias Hereditárias da Córnea/metabolismo , Opacidade da Córnea/diagnóstico , Opacidade da Córnea/metabolismo , Matriz Extracelular/patologia , Acuidade Visual , Amiloide/metabolismo , Colágeno/metabolismo , Córnea/metabolismo , Distrofias Hereditárias da Córnea/patologia , Distrofias Hereditárias da Córnea/fisiopatologia , Opacidade da Córnea/patologia , Opacidade da Córnea/fisiopatologia , Cristalinas/metabolismo , Diagnóstico Tardio , Diagnóstico Diferencial , Matriz Extracelular/metabolismo , Humanos , Hialina/metabolismo , Fotofobia/etiologia , Proteoglicanas/metabolismoRESUMO
PURPOSE: To evaluate the efficacy of mesenchymal stem cells (MSCs) to ameliorate the consequences of corneal alkali injuries. METHODS: Corneal alkali injuries were created in 30 rabbit eyes. The MSC group (n = 15) were treated with intrastromal and subconjunctival injections of phosphate-buffered saline (PBS) containing 2 × 10(6) MSCs and topical application. The control group (n = 15) was treated with PBS by the same applications forms. Drops of standard treatment (ascorbate 10 %, citrate 10 %, tobramycin, dexamethasone, Cyclogyl) were instilled for 2 weeks. Rabbits underwent slit-lamp examination, fluorescein staining, photography, and were evaluated for corneal neovascularization, opacification, and epithelial defects. Tear secretion and IOP were also evaluated. Furthermore, the concentration of Serumglutamic-pyruvic transaminase (SGPT) and vascular endothelial factor (VEGF) were measured. Immunohistochemistry was also performed for a-SMA and Ki-67. RESULTS: Eyes treated with MSCs showed better recovery. The mean neovascularized area was significantly smaller in the MSC group (p < 0.05). A significant difference in the degree of corneal opacification and re-epithelialization was also observed, as well as the IOP at 21 and 28 posttraumatic days (p < 0.05). Histology showed that MSCs resulted in almost normal architecture of eye tissues. After the MSCs infusion, SGPT and VEGF levels in cornea were significantly reduced. Immunohistochemistry demonstrated a reduction of a-SMA in the MSC group with higher mitotic-regenerative activity with the presence of Ki67. CONCLUSIONS: Our study represents a first step in understanding the possibilities of the MSC approach to treatment of alkali injuries of the cornea and shows that such an approach improves clinical outcomes and leads to better prognosis.
Assuntos
Queimaduras Químicas/terapia , Neovascularização da Córnea/terapia , Opacidade da Córnea/terapia , Queimaduras Oculares/induzido quimicamente , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Cicatrização/fisiologia , Actinas/metabolismo , Alanina Transaminase/sangue , Animais , Biomarcadores/metabolismo , Queimaduras Químicas/fisiopatologia , Neovascularização da Córnea/induzido quimicamente , Neovascularização da Córnea/fisiopatologia , Opacidade da Córnea/induzido quimicamente , Opacidade da Córnea/fisiopatologia , Modelos Animais de Doenças , Queimaduras Oculares/fisiopatologia , Citometria de Fluxo , Antígeno Ki-67/metabolismo , Coelhos , Reepitelização/fisiologia , Hidróxido de Sódio , Fator A de Crescimento do Endotélio Vascular/sangueRESUMO
PURPOSE: Ultrasound biomicroscopy (UBM) can be used to investigate the appearance of the anterior chamber in infants with congenital corneal opacity. This study investigated the association between the UBM-obtained clinical imaging of anterior chamber morphology and the clinical diagnosis in infants with congenital corneal opacity. SUBJECTS AND METHODS: This study involved 19 eyes of 10 consecutive infants with congenital corneal opacity, 13 eyes with Peters anomaly (PA, 7 cases) and 6 eye with sclerocornea (SC, 3 cases), recruited at the Kyoto Prefectural University of Medicine, Kyoto, Japan between September 2001 and January 2009. In each subject eye, UBM findings were compared with the clinical diagnosis based on slit-lamp findings and intraocular pressure (IOP). RESULTS: UBM findings revealed partial angle closure in 10 PA eyes and in 5 SC eyes, absence of Descemet's membrane in 13 eyes and 6 eyes, and funicular fiber from the iris in 12 eyes and 6 eyes. All 6 eyes with SC showed normal IOP, while 9 eyes with PA were diagnosed as glaucoma. CONCLUSION: Similarities in UBM appearance were observed between PA and SC. PA had a higher incidence of glaucoma; however, there was no relation between IOP and the UBM images.
Assuntos
Opacidade da Córnea/diagnóstico por imagem , Opacidade da Córnea/fisiopatologia , Pressão Intraocular , Pré-Escolar , Opacidade da Córnea/congênito , Feminino , Humanos , Lactente , Masculino , UltrassonografiaRESUMO
Omental cells (OCs) are shown to help wound healing. The purpose of this study is to investigate if OCs improve cornea repair after alkali injury by subconjunctival injection of activated OCs in rats. Forty eight hours after limbal corneal alkali injury, fresh isolated OCs were injected subconjunctivally into the recipient rat's eye. Prior to the injury and at 0, 4 and 8 days after injury, the eyes were examined using slit lamp biomicroscopy. Corneal opacification and corneal neovascularization were graded in a masked fashion. The inflammatory response to the injury was evaluated by counting neutrophil cell numbers in the cornea under microscope. There was no significant difference in corneal opacification between the control and OCs treatment groups; however, the corneal neovascularization was significantly less in the eyes treated with OCs as compared to the controls. Also OCs treatment markedly decreased neutrophil infiltration after corneal-limbal alkali injury. Our results suggest that OCs may have a beneficial role in corneal healing after limbal corneal alkali injury by suppressing inflammatory cell infiltrates and corneal neovascularization.