Distrofia corneal granular / Granular corneal dystrophy

Las distrofias corneales constituyen un conjunto de enfermedades que presentan, en su mayoría, una baja incidencia y se caracterizan por acúmulo de material hialino o amiloide que disminuyen la transparencia corneal. La distrofia granular es una enfermedad autosómica dominante que presenta opacidades grises en el estroma superficial central de la córnea y se hacen visibles en la primera y segunda décadas de la vida, lo que provoca disminución de la visión más significativa cerca de los 40 años de edad. Presentamos dos casos clínicos de distrofia granular en pacientes hermanos de diferentes sexos, quienes acudieron a la consulta y refirieron visi¾n nublada. El estudio de la historia familiar nos ayuda en el correcto diagnóstico y la biomicroscopia constituye el elemento más importante(AU)

Corneal dystrophies are a group of diseases that mostly have low incidence rates and are characterized by accumulation of hyaline or amyloid material that reduces the corneal transparency. Granular dystrophy is a dominant autosomal disease with gray opacities in the central superficial stroma of cornea, which are visible in the first and second decades of life and leads to significantly reduced vision when going into the 40 years of age. Here are two clinical cases of granular dystrophy in a pair of siblings who went to the doctor's because of blurred vision. The study of the family history helps the physician to reach a right diagnosis and the most important element is biomicroscopy(AU)

Distrofia corneal granular / Granular corneal dystrophy

Las distrofias corneales constituyen un conjunto de enfermedades que presentan, en su mayoría, una baja incidencia y se caracterizan por acúmulo de material hialino o amiloide que disminuyen la transparencia corneal. La distrofia granular es una enfermedad autosómica dominante que presenta opacidades grises en el estroma superficial central de la córnea y se hacen visibles en la primera y segunda décadas de la vida, lo que provoca disminución de la visión más significativa cerca de los 40 años de edad. Presentamos dos casos clínicos de distrofia granular en pacientes hermanos de diferentes sexos, quienes acudieron a la consulta y refirieron visión nublada. El estudio de la historia familiar nos ayuda en el correcto diagnóstico y la biomicroscopia constituye el elemento más importante(AU)

Corneal dystrophies are a group of diseases that mostly have low incidence rates and are characterized by accumulation of hyaline or amyloid material that reduces the corneal transparency. Granular dystrophy is a dominant autosomal disease with gray opacities in the central superficial stroma of cornea, which are visible in the first and second decades of life and leads to significantly reduced vision when going into the 40 years of age. Here are two clinical cases of granular dystrophy in a pair of siblings who went to the doctor's because of blurred vision. The study of the family history helps the physician to reach a right diagnosis and the most important element is biomicroscopy(AU)

[Surgical intrastromal keratopigmentation using tattoo ink]. / Queratopigmentación quirúrgica intraestromal con tinta para tatuaje cutáneo.

CASE REPORT: A 31-year-old woman who had undergone surgery for a congenital cataract as a newborn developed bilateral malignant glaucoma, which was refractory to medical-surgical treatment. The patient currently has terminal glaucoma and severe band keratopathy. For aesthetic purposes, we performed intrastromal keratopigmentation surgery using ink for skin tattoos supplied in sterile single-dose vessels. No secondary effects or complications were observed. DISCUSSION: Keratopigmentation or corneal tattooing can now be used as a last resort in patients who are unable to tolerate cosmetic contact or intraocular lenses, or in whom corneal transplant is contraindicated.

Bullous keratopathy as a progressive disease: evidence from clinical and laboratory imaging studies.

Bullous keratopathy is categorized as a corneal endothelial disease. However, pathological changes, including subepithelial fibrosis and the accumulation of extracellular matrix, have been detected in the corneal stroma of individuals with this condition. In vivo confocal microscopy allows the visualization of human corneal cellular structures and has provided information regarding how eyes are affected by various diseases. However, the determination of disease pathogenesis on the basis of in vivo confocal microscopic observations is problematic. We evaluated the structural alterations in the corneal stroma of eyes affected by bullous keratopathy using second harmonic generation microscopy and laser confocal immunofluorescence microscopy of whole-mount preparations. Using these approaches, we detected the transdifferentiation of keratocytes into fibroblasts and myofibroblasts at the anterior and posterior stroma and the presence of subepithelial fibrosis at the anterior stroma and disorganized collagen lamellae at the posterior stroma of the bullous keratopathy cornea. These changes were only detected in specimens from eyes with stromal edema lasting at least 12 months. Similar time-dependent changes were apparent by using in vivo confocal microscopy in the corneal stroma of patients with bullous keratopathy after performing a Descemet stripping automated endothelial keratoplasty surgery and were associated with an unfavorable outcome with regard to postoperative visual acuity. Our observations suggest that pathological changes in the corneal stroma of patients with bullous keratopathy are progressive and affect postoperative visual acuity after a Descemet stripping automated endothelial keratoplasty surgery is performed.

Abnormalities of stromal structure in the bullous keratopathy cornea identified by second harmonic generation imaging microscopy.

PURPOSE: To identify structural alterations in collagen lamellae and the transdifferentiation of keratocytes into myofibroblasts in the corneal stroma of bullous keratopathy (BK) patients and to examine the relation of such changes to the duration of stromal edema or the underlying cause of BK. METHODS: Six normal human corneas and 16 BK corneas were subjected to second harmonic generation (SHG) imaging microscopy to allow three-dimensional (3-D) reconstruction of collagen lamellae. Expression of α-smooth muscle actin (αSMA) was examined by immunofluorescence analysis and conventional laser confocal microscopy. RESULTS: Collagen lamellae were interwoven at the anterior stroma and uniformly aligned at the posterior stroma, whereas αSMA was not detected throughout the entire stroma of the normal cornea. Nine (56%) and 7 (44%) of the 16 BK corneas showed abnormal collagen structure at the anterior and posterior stroma, respectively. Expression of αSMA was detected in the anterior or posterior stroma of 7 (44%) and 6 (38%) of the 16 BK corneas, respectively. Disorganization of collagen lamellae and myofibroblastic transdifferentiation were detected only in corneas with a duration of stromal edema of at least 12 months. Corneas with BK as a result of birth injury showed abnormal collagen structure at the posterior stroma, whereas those with BK resulting from laser iridotomy did not. CONCLUSIONS: Changes in the structure of the entire stroma were detected in BK corneas with a duration of stromal edema of at least 12 months, suggesting that such changes may be progressive. In addition, the underlying cause of BK may influence structural changes at the posterior stroma.

Effects of aberrant Pax6 gene dosage on mouse corneal pathophysiology and corneal epithelial homeostasis.

BACKGROUND: Altered dosage of the transcription factor PAX6 causes multiple human eye pathophysiologies. PAX6⁺/⁻ heterozygotes suffer from aniridia and aniridia-related keratopathy (ARK), a corneal deterioration that probably involves a limbal epithelial stem cell (LESC) deficiency. Heterozygous Pax6(+/Sey-Neu) (Pax6⁺/⁻) mice recapitulate the human disease and are a good model of ARK. Corneal pathologies also occur in other mouse Pax6 mutants and in PAX77(Tg/-) transgenics, which over-express Pax6 and model human PAX6 duplication. METHODOLOGY/PRINCIPAL FINDINGS: We used electron microscopy to investigate ocular defects in Pax6⁺/⁻ heterozygotes (low Pax6 levels) and PAX77(Tg/-) transgenics (high Pax6 levels). As well as the well-documented epithelial defects, aberrant Pax6 dosage had profound effects on the corneal stroma and endothelium in both genotypes, including cellular vacuolation, similar to that reported for human macular corneal dystrophy. We used mosaic expression of an X-linked LacZ transgene in X-inactivation mosaic female (XLacZ(Tg/-)) mice to investigate corneal epithelial maintenance by LESC clones in Pax6⁺/⁻ and PAX77(Tg/-) mosaic mice. PAX77(Tg/-) mosaics, over-expressing Pax6, produced normal corneal epithelial radial striped patterns (despite other corneal defects), suggesting that centripetal cell movement was unaffected. Moderately disrupted patterns in Pax6⁺/⁻ mosaics were corrected by introducing the PAX77 transgene (in Pax6⁺/⁻, PAX77(Tg/-) mosaics). Pax6(Leca4/+), XLacZ(Tg/-) mosaic mice (heterozygous for the Pax6(Leca4) missense mutation) showed more severely disrupted mosaic patterns. Corrected corneal epithelial stripe numbers (an indirect estimate of active LESC clone numbers) declined with age (between 15 and 30 weeks) in wild-type XLacZ(Tg/-) mosaics. In contrast, corrected stripe numbers were already low at 15 weeks in Pax6⁺/⁻ and PAX77(Tg/-) mosaic corneas, suggesting Pax6 under- and over-expression both affect LESC clones. CONCLUSIONS/SIGNIFICANCE: Pax6⁺/⁻ and PAX77(Tg/-) genotypes have only relatively minor effects on LESC clone numbers but cause more severe corneal endothelial and stromal defects. This should prompt further investigations of the pathophysiology underlying human aniridia and ARK.

[Diffuse stromal corneal opacity and alterations of the hands]. / Diffuse stromale Hornhauttrübungen und Veränderungen der Hände.

Bilateral stromal corneal opacity is a differential diagnostic challenge for ophthalmologists. In this article 2 female patients aged 30 and 36 years old, respectively, with different degrees of expression of stromal diffuse corneal opacity will be presented. Patient 1 was of short stature (114 cm) and patient 2 was 172 cm in size. Both patients exhibited altered joint structures of the hands and feet and diffuse stromal corneal opacity. Furthermore, patient 1 had both mitral and aortal insufficiencies and patient 2 an aorta insufficiency. The stromal diffuse corneal opacity was indicative of Schleie syndrome. For patients with reduced vision a lamellary keratoplasty is to be recommended.

Bilateral congenital stromal cyst of the cornea.

Stromal corneal cysts have not been documented in histological studies of congenital corneal leukoma. We describe a bilateral congenital case in which the cysts occupied posterior excavations of the cornea and the affected infant developed angle-closure glaucoma.

[Corneal anomalies in murine trisomy 16]. / Minoranomalien der Hornhaut bei der murinen Trisomie 16.

BACKGROUND: The prevalence of human Down's syndrome is about 1:700. Investigations using animal models are therefore of clinical relevance for understanding its etiopathogenesis. No corneal changes have been reported with transgenic murine trisomy 16. METHODS: A total of 20 fetal mice (n=40 eyes) with experimentally induced trisomy 16 were investigated from day 18 of pregnancy in order to determine whether visible developmental disorders of the cornea occur. All specimen were investigated microscopically in serial sections. RESULTS: In addition to disturbances in systemic development, the transgenic mouse fetuses showed high rates of malformation of the eyes. Developmental and differentiation disorders of the corneal epithelial cell layers and structural disturbances of the corneal parenchyma were found. Our findings are the first demonstration of developmental disorders of the cornea in mouse fetuses with trisomy 16. These minor anomalies of the cornea could well have resulted in keratoconus if the animals had survived. CONCLUSIONS: Our findings in transgenic mouse fetuses with trisomy 16 correspond to the clinical pattern of Down's syndrome in humans. Disturbed development of lids and lenses have a high prevalence, whereas corneal hypoplasia is found less often.

Clinicopathological report of cerebroocular myopathy syndrome.

PURPOSE: To report a case of cerebroocular myopathy syndrome with a focal absence of the Descemet membrane. DESIGN: Clinicopathological case report. METHODS: A clinical and histopathologic examination of eye, brain, and viscera of a white male newborn of normal term, who died at 11 days of age with the diagnosis of cerebroocular myopathy syndrome. RESULTS: The autopsy revealed hazy left cornea, hypoplasia of the cerebellum, and corpus collusum with mild microcephaly. Microscopy of the left eye showed the additional findings of a central focal defect of the Descemet membrane with an absence of the posterior third of central corneal stroma and delicate fibrous strands connected to the iris. CONCLUSION: The absence of the Descemet membrane and the missing posterior corneal keratocytes as well as the fibrous strands connecting the iris are findings to be added to the previously reported signs of cerebro-ocular myopathy.

Efecto en el patrón topográfico postoperatorio con y sin secado transoperatorio del lecho estromal en Lasik / Effect of \"in site\" stromal transoperative drines in postoperative topographic patterns after Lasik

Se estudiaron un total de 60 ojos con diagnóstico de miopía con equivalente esférico mayor o igual a 8 DP y menor o igual a 11 DP, los cuales fueron sometidos a queratectomía fotorrefractiva con técnica de Lasik utilizando el equipo láser excimer Technolas 217 de Chiron y el microqueratomo automatizado Hansatome de Chiron, dividiéndose en dos grupos, a uno de los cuales se le efectuó secado transoperatorio del lecho estromal al 50 por ciento del tratamiento con esponja de merocel, y al segundo grupo no. Se practicaron estudios topográficos de elevación (Orbsacan) preoperatoria, a las 24 horas y 7 días de postoperatorio, se empleó como parámetro de evaluación del patrón de irregularidades el mapa de mejor adaptación a una esfera, tomando como referencia la esfera preoperatoria de base

Terrien's marginal degeneration associated with posterior polymorphous dystrophy.

PURPOSE: To document an association between Terrien's marginal degeneration and posterior polymorphous dystrophy. METHODS: A 23-year-old Saudi man presented with decreased vision, peripheral corneal thinning with vascularization and scarring, and abnormalities of the posterior stroma and Descemet's membrane. RESULTS: Clinical examination, corneal topography, and specular microscopy were consistent with a diagnosis of Terrien's marginal degeneration and posterior polymorphous dystrophy. CONCLUSION: We report the first case, to our knowledge, of the simultaneous occurrence of Terrien's marginal degeneration with posterior polymorphous dystrophy.

Radiating folds of descemet's membrane associated with deep stromal infiltrates

Dobras radiais da membrana de Descemet já foram descritas em associaçäo com olhos atróficos e também como sinal de perfuraçäo iminente. Os autores descrevem três casos onde essa alteraçäo foi encontrada em associaçäo com infiltrados profundos do estroma corneano, sendo dois deles devidos a infecçäo por Herpes Zoster e um por Haemophilus influenza. A pressäo intra-ocular era normal quando do surgimento das dobras e näo havia perfuraçäo ocular. Os autores acreditam que as dobras säo devidas a alteraçöes cicatriciais ao nível da membrana de Descemet

[Congenital corneal opacity caused by thickening of Bowman's membrane]. / Angeborene Hornhauttrübung durch Verdickung der Bowmanschen Membran.

Congenital corneal opacifications are rare, yet their causes are manifold. Only a few cases have been described in which the most striking histopathological feature is a thickening of Bowman's membrane. The authors found an isolated thickening of this membrane in the corneas of a baby who, shortly after birth, presented with corneal opacifications in both eyes. Only a few months after penetrating keratoplasty was performed the condition recurred. Bowman's membrane was found to be thickened in the graft as well.