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Purpose: To investigate the efficacy of corneal crosslinking (CXL) for pellucid marginal degeneration (PMD)., Setting: Medical University of Vienna., Design: Retrospective study., Methods: In eyes with a crab-claw pattern on corneal topography of a study cohort of 808 eyes, manual measurements of the cornea's thinnest point on the inferior vertical Scheimpflug image (mCTi) and on the superior vertical Scheimpflug image (mCTs) were conducted. Eyes with paralimbal thinning were supposed as having PMD and included. A ratio between mCTi and mCTs was calculated. CXL was performed by irradiation of the inferior periphery of the cornea. During the follow-up, the mCTi, the mean keratometry (K) values in a central zone of 5.0 mm and in a 2.5 mm zone of the inferior cornea and the topographical corneal astigmatism were measured. The corrected distance visual acuity (CDVA) was also evaluated. Patients were followed postoperatively for 12 months., Results: Forty-eight eyes showed a crab-claw pattern in corneal topography. Twenty-two eyes matched the inclusion criteria for PMD and 16 eyes underwent CXL. The mCTi increased during the 12-month follow-up. The K value in the 2.5 mm zone of the inferior cornea decreased after 1 year, whereas the K value in the central zone of 5.0 mm remained stable. The corneal astigmatism continuously decreased, and the CDVA improved after 1 year., Conclusion: Manual pachymetric measurements in Scheimpflug images showed the potential for screening for PMD and the evaluation of the efficacy of CXL in eyes with PMD in the study cohort. A thickening of the mCTi and a flattening in the inferior part of the cornea was observed., (Copyright © 2019 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate visual, refractive, topographic, and aberrometric outcomes of transepithelial phototherapeutic keratectomy (PTK) + corneal collagen crosslinking in the treatment of pellucid marginal degeneration., Methods: This retrospective study includes 20 eyes of 15 patients with pellucid marginal degeneration treated with transepithelial PTK + accelerated corneal collagen crosslinking. Visual acuity, refraction, topographic keratometry, pachymetry, and aberrations were recorded pretreatment and 6, 12, 24, and 36 months after treatment., Results: Stabilization in visual acuity was observed throughout the 36 months of follow-up (P > 0.05). The cylindrical value was significantly lower (P < 0.05) during the follow-up compared with the baseline (4.97 ± 2.00, 3.86 ± 2.01, 3.92 ± 2.27, 2.87 ± 1.70, and 3.28 ± 3.12 D at the baseline and postoperative 6th, 12th, 24th, and 36th month, respectively). Spherical equivalent was significantly lower at the 24th (P = 0.02) and 36th month (P = 0.01) follow-up intervals. A significant decrease (P < 0.05) in average keratometry readings was observed in all follow-up points (47.12 ± 4.66, 46.65 ± 4.38, 46.57 ± 4.57, 46.46 ± 4.81, and 46.27 ± 4.46 D, respectively). The maximum keratometry value remained stable (P > 0.05) in all visits (64.30 ± 10.70, 63.49 ± 10.05, 62.97 ± 9.50, 63.33 ± 10.06, and 62.27 ± 10.36 D, respectively). The Baiocchi Calossi Versaci index was significantly lower (P < 0.05) at all follow-up points compared with the baseline (3.21 ± 1.93, 2.99 ± 1.96, 2.96 ± 1.93, 2.82 ± 1.95, and 2.86 ± 1.99 μm, respectively). Central and minimum corneal thicknesses were significantly lower (P ≤ 0.01) compared with the baseline throughout the follow-up. Higher order aberration, trefoil, coma, and spherical aberration values remained stable during the follow-up compared with the baseline (P > 0.05)., Conclusions: The combination of transepithelial PTK with accelerated corneal collagen crosslinking seems to be an effective treatment in patients with pellucid marginal degeneration in the long-term.

Purpose: To describe and analyze the biomicroscopic features and in vivo confocal microscopy of the crystalline form of pre-Descemet corneal dystrophy (PDCD)., Methods: We examined two non-related families using biomicroscopy, in vivo confocal microscopy, and a genetic study using a gene panel test, looking for mutations in the PIKFYVE gene., Results: A slit-lamp examination of the first family revealed polychromatic crystalline punctiform opacities distributed all over the stroma in 8 of 11 family members in three generations with an autosomal dominant inheritance. The second family showed in three of four members in two generations the same opacities located in the pre-Descemet region. It was also a hint for autosomal dominant inheritance. The in vivo confocal microscopy identified numerous rounded and hyperreflective stromal particles measuring 10-15 μm in diameter, with the highest density in the posterior stroma and with normal keratocytes. No systemic disease was diagnosed. No variants or mutations were identified in PIKFYVE gene., Conclusions: Polychromatic deposits in patients with Punctiform and Polychromatic Pre-Descemet corneal dystrophy can be located not only in the deep stroma but also in the anterior and middle stroma. Our presentation reveals the possibility of considering this characteristic corneal disorder as a corneal dystrophy of its own and not as a subtype of pre-Descemet corneal dystrophy.

Purpose: Transforming growth factor beta-induced (TGFBI)-related dystrophies constitute the most common heritable forms of corneal dystrophy worldwide. However, other than the underlying genotypes of these conditions, a limited knowledge exists of the exact pathomechanisms of these disorders. This study expands on our previous research investigating dystrophic stromal aggregates, with the aim of better elucidating the pathomechanism of two conditions arising from the most common TGFBI mutations: granular corneal dystrophy type 1 (GCD1; R555W) and lattice corneal dystrophy type 1 (LCD1; R124C)., Methods: Patient corneas with GCD1 and LCD1 were stained with hematoxylin and eosin and Congo red to visualize stromal nonamyloid and amyloid deposits, respectively. Laser capture microdissection was used to isolate aggregates and extracted protein was analyzed by mass spectrometry. Proteins were identified and their approximate abundances were determined. Spectra of TGFBIp peptides were also recorded and quantified., Results: In total, three proteins were found within GCD1 aggregates that were absent in the healthy control corneal tissue. In comparison, an additional 18 and 24 proteins within stromal LCD1 and Bowman's LCD1 deposits, respectively, were identified. Variances surrounding the endogenous cleavage sites of TGFBIp were also noted. An increase in the number of residues experiencing cleavage was observed in both GCD1 aggregates and LCD1 deposits., Conclusions: The study reveals previously unknown differences between the protein composition of GCD1 and LCD1 aggregates, and confirms the presence of the HtrA1 protease in LCD1-amyloid aggregates. In addition, we find mutation-specific differences in the processing of mutant TGFBIp species, which may contribute to the variable phenotypes noted in TGFBI-related dystrophies.

Purpose: To report the long-term clinical outcome of a patient diagnosed as having Terrien marginal degeneration (TMD) who was subjected to corneal collagen cross-linking (CXL) with ultraviolet-A and riboflavin in both eyes., Methods: Topographical changes were assessed by high-resolution Scheimpflug imaging and anterior segment optical coherence tomography. Eccentric epithelium-off CXL was performed in both eyes while protecting the corneal limbus. Irradiation was performed with a fluence of 5.4 J/cm(2), using 3 mW/cm(2) for 30 minutes., Results: Five years of postoperative follow-up showed regression of the keratometric values, a local thickening of the corneal stroma, and bilateral improvement of corrected distance visual acuity., Conclusions: CXL may arrest progression in TMD and even reverse the catabolic process in the corneal stroma. CXL might represent an alternative therapeutic approach for the management of TMD., (Copyright 2014, SLACK Incorporated.)

Three genetic corneal dystrophies [congenital hereditary endothelial dystrophy type 2 (CHED2), Harboyan syndrome and Fuchs endothelial corneal dystrophy] arise from mutations of the SLC4a11 gene, which cause blindness from fluid accumulation in the corneal stroma. Selective transmembrane water conductance controls cell size, renal fluid reabsorption and cell division. All known water-channelling proteins belong to the major intrinsic protein family, exemplified by aquaporins (AQPs). Here we identified SLC4A11, a member of the solute carrier family 4 of bicarbonate transporters, as an unexpected addition to known transmembrane water movement facilitators. The rate of osmotic-gradient driven cell-swelling was monitored in Xenopus laevis oocytes and HEK293 cells, expressing human AQP1, NIP5;1 (a water channel protein from plant), hCNT3 (a human nucleoside transporter) and human SLC4A11. hCNT3-expressing cells swelled no faster than control cells, whereas SLC4A11-mediated water permeation at a rate about half that of some AQP proteins. SLC4A11-mediated water movement was: (i) similar to some AQPs in rate; (ii) uncoupled from solute-flux; (iii) inhibited by stilbene disulfonates (classical SLC4 inhibitors); (iv) inactivated in one CHED2 mutant (R125H). Localization of AQP1 and SLC4A11 in human and murine corneal (apical and basolateral, respectively) suggests a cooperative role in mediating trans-endothelial water reabsorption. Slc4a11(-/-) mice manifest corneal oedema and distorted endothelial cells, consistent with loss of a water-flux. Observed water-flux through SLC4A11 extends the repertoire of known water movement pathways and call for a re-examination of explanations for water movement in human tissues.

Purpose: Types 1 and 2 granular corneal dystrophies (GCD) are primarily associated with accumulation of the R555W and R124H mutant transforming growth factor β-inducible proteins (TGFBIp) in corneal stroma, respectively. However, specific components of TGFBIp responsible for granular deposits have not been delineated. This study was undertaken to identify the mutant TGFBIp components potentially responsible for GCD., Methods: Recombinant TGFBIp of wild-type (WT) and three mutants, R124C, R124H, and R555W, were generated in HEK293FT cells. WT and TGFBIp mutants were collected from cell lysates. Immunoblot analyses were performed with five different antibodies directed against various regions of WT TGFBIp., Results: WT and TGFBIp mutants showed differential reactivities with these antibodies. In contrast to our prior observation in purified WT and TGFBIp mutants, TGFBIp from cell lysates were less prone to polymerize. A unique 35 kD fragment was detected in cell lysates of R555W and R124H, but not in those of WT or R124C, by a commercial antibody raised against amino acids (a.a.) 199-406 of TGFBIp., Conclusions: Monomeric and polymeric WT and TGFBIp mutants were observed in vitro. The 35 kD fragment found only in R555W and R124H, but not in WT and R124C cell lysates, is likely a degraded TGFBIp derived from the central domain of these mutants and this fragment may be contributory to the nonamyloid granular deposits observed in GCD 1 and 2.

Different types of granular corneal dystrophy (GCD) and lattice corneal dystrophy (LCD) are associated with mutations in the transforming growth factor beta induced gene (TGFBI). These dystrophies are characterized by the formation of non-amyloid granular deposits (GCDs) and amyloid (LCD type 1 and its variants) in the cornea. Typical corneal non-amyloid deposits from GCD type 2 (R124H), amyloid from a variant of LCD type 1 (V624M) and disease-free tissue controls were procured by laser capture microdissection and analyzed by tandem mass spectrometry. Label-free quantitative comparisons of deposits and controls suggested that the non-amyloid sample (R124H) specifically accumulated transforming growth factor beta induced protein (TGFBIp/keratoepithelin/βig-h3), serum amyloid P-component, clusterin, type III collagen, keratin 3, and histone H3-like protein. The amyloid (V624M) similarly accumulated serum amyloid P-component and clusterin but also a C-terminal fragment of TGFBIp containing residues Y571-R588 derived from the fourth fasciclin-1 domain (FAS1-4), apolipoprotein E and apolipoprotein A-IV. Significantly, analyses of the amyloid sample also revealed the presence of the serine protease Htr (High-temperature requirement) A1 and a number of proteolytic cleavage sites in the FAS1-4 domain of TGFBIp. These cleavage sites were consistent with the ligand binding and proteolytic activity of HtrA1 suggesting that it plays a role in the proteolytic processing of the amyloidogenic FAS1-4 domain. Taken together, the data suggest that the amyloidogenic-prone region of the fourth FAS1 domain of TGFBIp encompasses the Y571-R588 peptide and that HtrA1 is involved in the proteolytic processing of TGFBIp-derived amyloid in vivo., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Purpose: Congenital stromal corneal dystrophy (CSCD) is characterized by stromal opacities that morphologically are seen as interlamellar layers of amorphous substance with small filaments, the nature of which has hitherto been unknown. CSCD is associated with truncating mutations in the decorin gene (DCN). To understand the molecular basis for the corneal opacities we analyzed the expression of decorin in this disease, both at the morphologic and the molecular level., Methods: Corneal specimens were examined after contrast enhancement with cuprolinic blue and by immunoelectron microscopy. Decorin protein from corneal tissue and keratocyte culture was studied by immunoblot analysis before and after O- and N-deglycosylation. The relative level of DCN mRNA expression was examined using Q-RT-PCR, and cDNA was sequenced. Recombinant wild-type and truncated decorin transiently expressed in HEK293 cells were analyzed by gel filtration and immunoblotting., Results: The areas of interlamellar filaments were stained by cuprolinic blue. Immunoelectron microscopy using decorin antibodies revealed intense labeling of these areas. Both wild-type and truncated decorin protein was expressed in corneal tissue and keratocytes of affected persons. When decorin expressed in HEK293 cells was examined by gel filtration, the truncated decorin eluted as high molecular weight aggregates., Conclusions: Accumulation of decorin was found in the interlamellar areas of amorphous substance. The truncated decorin is present in CSCD corneas, and there is evidence it may aggregate in vitro. Thus, decorin accumulation appears to contribute to the stromal opacities that are characteristic of CSCD.

Purpose: To report the results of corneal collagen cross-linking (CXL) with riboflavin and ultraviolet A irradiation in a patient affected by pellucid marginal degeneration (PMD)., Methods: A 43-year-old man with bilateral PMD underwent CXL in the left eye. The treatment was performed in standard fashion with the exception of slightly inferior decentration of the 9 mm-diameter irradiated area preserving an untreated surface area 1 mm from the limbus., Results: Epithelial regrowth was complete after 4 days' use of a bandage soft contact lens. No side effects or damage to the limbal region were observed during re-epithelialization or during follow-up. Corrected distance visual acuity improved from 20/200 to 20/63 at 3 months and was stable through the 12-month interval. Keratometric astigmatism showed a 1.40-diopter (D) reduction and the power of ectasia apex decreased from 82.00 D to 78.00 D., Conclusions: Corneal collagen CXL was a safe tool in the management of PMD, improving some parameters in advanced stages of the disease.

The aim of the present study was to investigate the expression pattern of different cell adhesion molecules in corneal stromal dystrophies. Fifteen corneal buttons from patients diagnosed with three different types of stromal corneal dystrophies and healthy corneas were investigated. Paraffin embedded sections were stained immunohistochemically with monoclonal antibodies against human intercellular adhesion molecule-1 (ICAM-1), endothelial selectin (E-selectin) and endothelial cadherin (E-cadherin) using the avidin-biotin-peroxidase-complex technique. The sections were compared to normal eye bank controls. In corneas from granular dystrophy patients ICAM-1 was expressed focally in epithelial cells and in keratocytes, and expressed diffusely in endothelial cells. In corneas from macular dystrophy patients diffuse epithelial staining was observed and the stromal and endothelial expression was found to be similar to that of granular dystrophy. In lattice dystrophy, only the epithelial cells and endothelium were intensively positive for ICAM-1. E-selectin was not present on any layer of the corneal specimens. E-cadherin was observed only in the epithelium of all three types of corneal dystrophies. Normal corneas did not express any of the investigated adhesion molecules. We found different expression patterns of adhesion molecules in corneas from stromal dystrophies. Our results suggest that adhesion molecules may be involved in the pathogenesis of corneal stromal dystrophies.

Purpose: To analyze components of the deposits in the corneal flap interface of granular corneal dystrophy type II (GCD II) patients after laser in situ keratomileusis (LASIK)., Methods: Four corneal GCD II specimens displaying disease exacerbation after LASIK were analyzed. Three of these specimens included the recipient corneal button after penetrating keratoplasty or deep lamellar keratoplasty for advanced GCD II after LASIK. The fourth specimen, a similar case of GCD II after LASIK, included the amputated corneal flap. Specimens were processed for histopathologic and immunohistochemical analyses., Results: Corneal stromal deposits in the LASIK flaps of all specimens were stained with 3 anti-transforming growth factor-beta-induced protein (TGFBIp) antibodies. The deposits displayed bright red color staining with Masson trichrome; however, negative staining was seen with Congo red, suggesting that hyaline is the main component localizing to the TGFBIp deposits rather than amyloid., Conclusions: Amorphous granular material deposited along the interface of the LASIK flap in GCD II corneas is composed mainly of hyaline deposits.

Purpose: To report the clinical and histopathologic features of accelerated TGFBI protein (TGFBIp) deposition after lamellar keratorefractive surgery in a patient with combined granular-lattice corneal dystrophy (CGLCD) who underwent bilateral corneal transplantation., Design: Interventional case report., Methods: A 28-year-old woman with a presumed TGFBI corneal dystrophy, but who retained best corrected visual acuity of 20/20 in each eye, underwent myopic laser-assisted in-situ keratomileusis (LASIK) both eyes (OU). For definitive diagnosis of the corneal dystrophy, buccal epithelial cells were collected as a source of genomic DNA and screening of TGFBI exons 4 and 12 was performed., Results: Four months after the performance of an uncomplicated LASIK procedure, the patient's uncorrected visual acuity was 20/15 OU. Over the following two years, the appearance of confluent white stromal deposits at the LASIK flap interface resulted in disabling glare and a reduced best-corrected visual acuity of 20/40 OU. Corneal transplantation was performed in each eye, and histopathologic examination of the excised corneal buttons was performed. Eosinophilic material that stained positively with the Masson trichrome stain was present in the LASIK flap interface, as well as in the stroma of the flap and the anterior portion of the stromal bed. No amyloid deposits were identified with the Congo red stain. Screening of TGFBI exons 4 and 12 revealed the Arg124His mutation associated with CGLCD., Conclusions: Accelerated deposition of TGFBIp may occur after lamellar corneal surgery in patients with CGLCD. Therefore, LASIK surgery should be avoided in patients with any of the TGFBI dystrophies, and surgeons should be aware of the potential for rapid interface TGFBIp deposition after lamellar corneal surgery.

Purpose: To identify the genetic defect in a Belgian family with congenital stromal corneal dystrophy., Design: Case report and result of deoxyribonucleic acid (DNA) analyses., Methods: DNA sequencing of polymerase chain reaction (PCR) products generated from amplification of exons and adjacent introns of the decorin gene., Results: The family consisted of a mother and her son, both suffering from congenital stromal corneal dystrophy. In both individuals, a single base pair deletion (c.941delC) in the coding sequence of the decorin gene was demonstrated, predicting a C-terminal truncation of the decorin protein (p.Pro314fsX14)., Conclusion: This is the second family with congenital stromal corneal dystrophy of the cornea in which a frame shift mutation in the decorin gene has been detected. Both in this family and in a previously reported Norwegian family, a decorin protein missing the 33 C-terminal amino acids is predicted. This observation strongly supports a role for decorin in the pathogenesis of this disorder.

Purpose: To investigate corneal deposits associated with kerato-epithelin (KE) in three corneal dystrophies harboring mutations at Arg-124 in the BIGH3 gene., Methods: Six patients with Avellino corneal dystrophy (ACD) associated with R124H, one patient with superficial granular corneal dystrophy (SGCD) associated with R124L, and seven patients with lattice corneal dystrophy type 1 (CDL1) associated with R124C were examined. Corneal buttons obtained during keratoplasties were stained with Masson's trichrome and with Congo red, and immunostained with antibodies specific for N-terminal and C-terminal portions of KE (KE-15 and KE-2, respectively)., Results: In all corneas with ACD, subepithelial to midstromal deposits of granular material stained with KE-2 and KE-15. However, deep stromal deposits containing amyloid reacted with KE-2, but not KE-15. Granular deposits in the subepithelial layer observed in SGCD stained intensely with KE-2 and KE-15. In all corneas with CDL1, subepithelial and midstromal amyloid deposits stained with KE-2; these deposits did not stain with KE-15. Deposits between the epithelial layer and Bowman's layer stained with Masson's trichrome but not with Congo red in five of the seven corneas; these deposits were stained with both KE-2 and KE-15., Conclusions: Deposits in corneal buttons involved by ACD, SGCD, and CDL1 included forms of the BIGH3 gene product, KE. An N-terminal sequence of KE may be related to formation of amyloid associated with R124 mutations.

Granular-lattice (Avellino) corneal dystrophy has rarely been reported in the literature. It consists of a combination of granular and lattice dystrophy. We describe the histopathologic examination of the corneal button of one Japanese patient who had undergone unilateral keratoplasty because of severely decreased vision caused by what had been diagnosed clinically as granular dystrophy. However, on pathologic examination, lesions characteristic of both granular dystrophy and lattice dystrophy were found. We also describe 2 Japanese patients who had a clinical appearance characteristic of both granular and lattice dystrophy. Granular-lattice corneal dystrophy was found in a wider geographic distribution than previously proposed and should not be named after the geographic area.

Purpose: To report the presence of abnormal endothelium that extruded into the posterior corneal stroma in a patient with posterior polymorphous dystrophy., Methods: The corneal button of a man who underwent penetrating keratoplasty for posterior polymorphous dystrophy was examined by light and electron microscopy. Immunoperoxidase staining for cytokeratins, vimentin, and the endothelial antigen recognized by monoclonal antibody 2B4.14.1 antigen was performed. Two-color immunofluorescence staining for simultaneous detection of cytokeratins and 2B4.14.1 antigen was also done., Results: Much of the endothelium had characteristic features of epithelium-like cells, and abnormalities in Descemet's membrane were present. Curious oval and slit-like spaces in the posterior stroma were lined by epithelium-like endothelial cells and were continuous with the anterior chamber through defects in Descemet's membrane., Conclusion: These abnormalities in the posterior stroma have not previously been described in histopathologic reports of posterior polymorphous corneal dystrophy and are likely an unusual variation in the spectrum of this hereditary disorder.

Purpose: Synchrotron x-ray diffraction experiments indicate that corneas with macular corneal dystrophy (MCD) contain unusual 4.6-A periodic repeats thought to reside in proteoglycans or glycosaminoglycans. Recently the 4.6-A x-ray reflection was found to be significantly diminished after incubation of MCD specimens in buffer containing chondroitinase ABC or N-glycanase. We examined the sulfated proteoglycans in these glycosidase-digested MCD corneas., Methods: Transmission electron microscopy was used in conjunction with cuprolinic blue-staining for sulfated proteoglycans., Results: Incubation of an MCD specimen in enzyme buffer left both small and large proteoglycan filaments in the stromal matrix, whereas incubation in the presence of chondroitinase ABC removed these molecules from the tissue. Incubation in buffer containing N-glycanase, on the other hand, removed the large proteoglycan filaments from the MCD stroma but left unaffected the small collagen-associated proteoglycans., Conclusion: These results are consistent with the interpretation that 4.6-A periodic repeats in MCD corneas reside in large sulfated proteoglycan filaments (or aggregates thereof) that may contain chondroitin/dermatan sulfate and keratan sulfate or keratan components.

Background: The pathogenesis of Schnyder dystrophy is thought to be a primary abnormality of corneal lipid metabolism resulting in opacification secondary to lipid accumulation. Histochemical investigations have suggested the accumulated lipid includes unesterified cholesterol; however, quantitative analysis has not been done., Methods: Quantitative biochemical analysis was performed on a corneal button obtained from a patient with clinically and pathologically proven Schnyder dystrophy. Results were compared with four age-, sex-, and size-matched corneal buttons obtained from cadaveric eyes., Results: Corneal lipid accumulated in Schnyder dystrophy predominantly is composed of phospholipid, free cholesterol, and cholesterol ester. These constituents were markedly elevated in the Schnyder cornea when compared with cadaveric control corneas as follows: (1) phospholipid, 23.6 versus 4.05 mg/g; (2) unesterified cholesterol, 6.99 versus 0.52 mg/g; and (3) cholesterol ester, 3.16 versus 0.26 mg/g., Conclusion: Phospholipid, unesterified cholesterol and cholesterol ester are the predominant lipids in Schnyder dystrophy. The pathogenesis may be a primary disorder of corneal lipid metabolism.

Keratocytes are differentiated mesenchymal fibroblast which are specialized in the production and maintenance of the transparent corneal stroma. These elongated cells with large nuclei and scant cytoplasm produce the collages, proteoglycans, and glycoproteins which make up the stroma, as well as the enzymes involved in post-translation modifications and catabolism of these macromolecules. The characteristic morphological features and specific metabolic activity of keratocytes undergo significant changes during tissue repair and in several corneal diseases. Alterations in keratocyte biosynthetic activity, regardless of their cause, ultimately lead to fibrillar alterations responsible for a loss of corneal transparency.

Fuchs' endothelial dystrophy is commonly regarded as an endothelial cell disorder. In the present study we compared glycoconjugates of Fuchs' and normal corneas using FITC conjugated lectins [peanut agglutinin (PNA), castor bean agglutinin (RCA120), soybean agglutinin (SBA), and wheat germ agglutinin (WGA)]. Our results showed increased staining with RCA120 and PNA in the posterior region of the Fuchs' corneas, indicating an accumulation of terminal beta-galactose and B-D-galactose (1-3)-D-N-acetylgalactosamine residues. The stromal and epithelial regions of normal and Fuchs' corneas exhibited similar staining patterns with all lectins tested. Our collagen studies showed an increased extractability and abnormal amino acid analyses of collagen from Fuchs' corneas as compared with normals. The purified collagens did have similar banding patterns by sodium dodecyl sulfate gels. However, further characterization by 125(1) two-dimensional peptide mapping revealed that Fuchs' alpha 1-sized chains contained fingerprints that were distinctly different from normal cornea stromal collagen. These data suggest that in addition to abnormal accumulation of RCA120- and PNA-specific glycoconjugates in the posterior cornea, Fuchs' corneas contained stromal collagens with altered biochemical properties. We postulate that the characteristic deterioration of endothelial function in Fuchs' dystrophy may compromise the microenvironment of the stroma and its keratocytes, and thereby lead to an altered collagenous extracellular matrix.

Corneal dystrophies are distinctive clinically and histopathologically; however, variations do occur. We present two cases of stromal amyloidosis from one family masquerading other corneal dystrophy. The two cases are from a six-generation family with an autosomal dominant corneal dystrophy resembling Reis-Bucklers' dystrophy. In these cases, neither the propositus nor other family members showed typical lattice lines. Light and electron microscopy of the obtained corneal buttons disclosed amyloid stromal deposits. The clinicopathologic correlation of these cases suggests that this family represents a variant of stromal amyloid dystrophies.