Search

PURPOSE To describe the histopathological characteristics of limbal stem cell deficiency (LSCD) due to chronic vernal keratoconjunctivitis (VKC). METHODS This retrospective study included 14 eyes of 13 patients who underwent simple limbal epithelial transplantation for total LSCD from 2017 to 2018. The histological characteristics of the excised fibrovascular pannus were compared between 2 groups of 7 eyes, each with LSCD due to VKC and chemical burns (CB). Histological characteristics and type of inflammation were studied using special stains and immunohistochemistry. Fisher exact test was used to detect the statistical significance of the histological differences between both groups. RESULTS Epithelial hypertrophy, epithelial downgrowth, and eosinophilic infiltration were noted in all eyes in the VKC group (7/7, 100%). Epithelial hypertrophy was noted in 3 of the 7 (42.8%) eyes in the CB group, whereas epithelial downgrowth and eosinophilic infiltrates were absent. The average chronic inflammatory score of the pannus (5.28) was higher in VKC than in CB (3.85; P = 0.1080). The presence of goblet cells was higher in the CB group (5/7, 1.4%) than in the VKC group (3/4, 2.8%), although not statistically significant. Other histological differences between the groups were not statistically significant. CONCLUSIONS The histopathological features of LSCD in VKC reveal some distinctive characteristics. These include the presence of epithelial downgrowth, eosinophilic infiltration, and epithelial solid and cystic implants. Although this information may be used to establish the diagnostic criteria for VKC as the cause of LSCD, further studies are needed to elucidate the reasons behind these unique findings.

Purpose To characterize the clinical presentation of limbal stem cell deficiency (LSCD) associated with glaucoma surgeries. Methods This is a retrospective cross-sectional study of patients with LSCD and glaucoma who presented to the Stein Eye Institute at the University of California, Los Angeles, between 2009 and 2018. Patients who underwent trabeculectomy and/or aqueous shunt surgery were included. The severity of LSCD was staged using global consensus guidelines and a clinical scoring system, and basal epithelial cell density was measured by in vivo confocal microscopy. Anatomic locations of glaucoma and non-glaucoma surgeries, locations of LSCD, and severity of LSCD were compared. Results Fifty-one eyes of 41 patients with LSCD associated with glaucoma surgery were included in this study. LSCD in these patients uniquely featured sectoral replacement of corneal epithelium by conjunctival epithelium, without corneal neovascularization or pannus. The sites of glaucoma surgery strongly correlated with the locations of LSCD (P = 0.002). There was a trend toward increased severity of LSCD in eyes with 2 or more glaucoma surgeries as compared to eyes with 1 glaucoma surgery, although the difference did not reach statistical significance (P = 0.3). Use of topical glaucoma medications correlated with LSCD severity, while the impact of antimetabolites did not reach statistical significance. The location of glaucoma drainage surgery is correlated with the location of LSCD. Conclusions LSCD associated with glaucoma surgery has clinical features distinct from LSCD resulting from other etiologies. Further study is required to delineate the full impact of glaucoma surgery on limbal stem cell function and survival.

Purpose To describe the efficacy of autologous serum (AS) eye drops to reverse severe contact lens (CL)-induced limbal stem cell (LSC) deficiency (LSCD). Methods This is a prospective, uncontrolled, interventional case series that enrolled 20 eyes of 14 consecutive patients diagnosed with severe CL-induced LSCD at presentation, based on clinical examination, at a tertiary referral center for the period December 2016 to December 2018. All eyes underwent AS treatment for at least 2 weeks with a follow-up for at least 2 months. Demographic data and treatment outcomes were collected and analyzed. Results The mean patient age at presentation was 30.5 years (range, 19-49 years). The mean duration of soft contact lens wear was 15.6 years (SD, 7.58 years; range, 5-31 years). All study eyes had pain and blurred vision at presentation. All eyes had recurrent or persistent corneal epithelial defect, stromal scarring and opacity, and superficial vascularization and peripheral pannus at presentation. Aggressive treatment with AS succeeded in all eyes. Signs and symptoms of LSCD stabilized in all eyes within 2 weeks and resolved in 6 eyes (30.0%) in 2 weeks, 9 eyes (45.0%) in 4 weeks, and 5 eyes (25.0%) in 8 weeks. The mean follow-up time was 9.45 ± 1.79 weeks (range, 8-24 weeks). Conclusions Early identification and aggressive treatment of the ocular surface disease with AS can medically reverse severe CL-induced LSCD and prevent the need for surgical intervention.

Purpose To report the rare coexistence of keratoconus and Stevens-Johnson syndrome (SJS) managed with scleral contact lenses (ScCLs). Methods This is a retrospective case series. Five patients (9 eyes) who had coexisting SJS and corneal ectasia were identified from the database during the 2-year period. Diagnosis of SJS was based on a positive history of drug reactions, signs of ocular surface disease, and the presence of keratinization of lid margins. Keratoconus was diagnosed by slit-lamp biomicroscopy. Results Five eyes of 3 patients had coexisting SJS and keratoconus and were dispensed with ScCLs (PROSE, prosthetic replacement of the ocular surface ecosystem; Boston Foundation for Sight, Needham Heights, MA). All these patients had photophobia. Visual acuity improved in all these patients with ScCL wear. Two patients (4 eyes) were excluded from this study because they had SJS with generalized corneal thinning from limbus to limbus, corneal opacification, and pannus. One patient developed deep vessels in the cornea on prolonged ScCL wear. Reduction in the ScCL wear schedule and change of material with a higher Dk resulted in regression of vascularization. Case 3 developed conjunctival congestion and was uncomfortable wearing ScCLs, although visual acuity was 20/40. He discontinued using ScCL wear. Conclusions Keratoconus, a noninflammatory condition of the cornea coexisted with inflammatory SJS. Managing such patients with ScCLs may improve vision and comfort.

PURPOSE Typically, we observe an unintended hyperopic shift after phototherapeutic keratectomy (PTK). Despite a clear optical axis, elevations of the mid-peripheral cornea often lead to remarkable visual impairment in Salzmann nodular degeneration (SND). The aim of this study was to analyze the effect of mechanical pannus removal and PTK on the corneal curvature in SND. METHODS Fifteen eyes of 10 patients with visual impairment caused by SND were treated with combined pannus removal and PTK using a masking fluid. Mean age was 53 years. We analyzed best-corrected visual acuity, central corneal power (in diopters, D), spherical equivalent (in D), and irregularity of corneal topography (Index of Surface Variance, Pentacam). RESULTS Best corrected visual acuity before PTK was 0.64 (median) and improved to 0.85 (median) after the surgical procedure. Mean spherical equivalent was reduced by 1.82 ± 1.4 D from +2.53 D preoperatively to +0.75 D postoperatively (P = 0.001). Mean central corneal power increased by 3.18 ± 3.5 D from 39.8 ± 4.6 D preoperatively to 43 ± 1.7 D postoperatively (P = 0.013). Topographic irregularity normalized from 83.9 ± 53.7 (27-204) to 33.3 ± 14.3 (20-56; Index of Surface Variance) (P = 0.016). CONCLUSIONS In SND, asymmetric tear film pooling caused by nodules located in the mid-periphery of the cornea may lead to an "optical cornea plana," which results in a marked hyperopic shift accompanied with high irregular astigmatism. Pannus removal combined with excimer laser PTK may restore visual performance, at least in part, because of a myopic shift and regularization of the corneal curvature.

Purpose To describe the clinical features of patients affected with vernal keratoconjunctivitis (VKC) with associated limbal stem cell deficiency (LSCD). Methods In a retrospective observational case series, data relating to 49 eyes of 27 patients with VKC and features of LSCD seen from January 2000 to August 2005 at the Cornea Service of LV Prasad Eye Institute were reviewed. Detailed history, visual acuity at presentation,clinical findings, disease activity, duration of complaints, and extent of LSCD and management were noted. The presence of concurrent keratoconus and other ocular or systemic disorders if any were recorded. Results During this period, 2225 patients with VKC were seen at our institute. Of the 49 eyes, (1.2%) showed features of LSCD. The mean age was 21.37 6 10.14 years. The male to female ratio was 4 to 1. Twenty-two cases had bilateral disease, and 5 had unilateral affection. The visual acuity at presentation ranged from hand motions to 20/20. The duration of disease ranged from 1 to 25 years, with a mean of 10 6 6.66 years. Total LSCD was seen in 33 eyes (67.3%), and partial LSCD was seen in 16 (33%). Disease at the time of presentation was active in 15 cases (55.5%) and was quiescent in 12 cases (44.5%). Pannus resection with amniotic membrane graft was done in 5 eyes. Live-related allolimbal transplantation was done in 6 eyes of 3 patients. VKC patients with or without associated LSCD had similar characteristics, but the age of presentation was lower inpatients without LSCD (P = 0.0005, unpaired Student t test), and the duration of disease was shorter (P , 0.0001, unpaired Student t test). Conclusions LSCD seems to be one of the complications of long-standing VKC, contributing to severe visual impairment in young individuals. The chronic nature and prolonged duration of the disease may be responsible for this secondary ocular surface affection, leading to the clinical manifestation of LSCD.

PURPOSE: To investigate the prognosis of paraquat-induced ocular surface injury and the therapeutic efficacy of amniotic membrane transplantation for the treatment of ocular surface damage. METHODS: Twenty patients (26 eyes) with ocular surface injury caused by paraquat were studied. Twelve patients (14 eyes) underwent amniotic membrane transplantation combined with medical treatment (group A), and 8 patients (12 eyes) received medical treatment only (group B). Visual acuity, time to epithelial defect closure, stromal haze, and complications were analyzed. RESULTS: The grade of the ocular surface injury was mild in 19 eyes (73.1%). Visual acuity improved in 20 eyes (76.9%). The epithelial defect healed completely in 25 eyes (96.2%), with a mean healing time of 16.04 +/- 6.22 days. At the final visit, 80.8% of cases had no stromal haze. The mean time to epithelial defect closure was 13.43 +/- 3.55 days in group A and 19.18 +/- 7.25 days in group B (P = 0.03). Complications included punctal stenosis (2 eyes) and pannus (1 eye) in group A and conjunctivalization (1 eye) and symblepharon (1 eye) in group B. CONCLUSIONS: Paraquat-induced ocular surface injury had a relatively good prognosis. Amniotic membrane transplantation was helpful in shortening the time to closure of the epithelial defect.

Purpose To evaluate the clinical use of optical coherence tomography (OCT) in optimizing surgical treatment strategies for conjunctivalized corneas secondary to ocular burns. Methods This noncomparative observational study included 25 patients with stable ocular burns and conjunctivalized corneas. OCT was performed on each eye. The thickness of corneal opacity or pseudopterygium and the underlying healthy stroma were measured. Individual surgical strategies were performed based on clinical examination and OCT images. Results Three types of conjunctivalized corneas were evaluated, including conjunctival pannus (4 of 25), pseudopterygium (10 of 25), and a white fibrovascular membrane (11 of 25). All 25 patients received a procedure of allograft limbal stem cell transplantation. In addition, with information provided in OCT images, 8 patients had combined lamellar keratoplasties; 3 patients had deep anterior lamellar keratoplasties, and 2 patients received penetrating keratoplasties. The remaining 12 patients received limbal stem cell transplantation alone. All fibrovascular tissues were successfully removed from the cornea in all patients. Conclusions OCT is a valuable method in the evaluation of conjunctivalized corneas. This is helpful in determining the surgical treatments for individual patients, allowing for less corneal graft rejection and making good use of corneal donors.

Salzmann's nodular degeneration is a rare, noninflammatory, slowly progressive, degenerative condition. Bluish-white nodules raised above the surface of the cornea characterize it. It has usually developed in corneas with a history of phlyctenulosis, trachoma, vernal keratoconjunctivitis, measles, scarlet fever, and various other viral diseases. However, today the majority of cases have been seen without recognized previous keratitis. It is composed of dense irregularly arranged collagen tissue with hyalinization between epithelium and Bowman's layer or beyond. Manual removal, phototherapeutic keratectomy (PTK) with or without the use of topical mitomycin-C, lamellar or penetrating keratoplasty have been used in the treatment of this disease. Salzmann's nodular degeneration does not seem to consist of one clinical entity. In some cases, elevated and pannus-like tissue can be separated easily from the corneal surface leaving Bowman's layer almost untouched. In these eyes, subsequent PTK may be necessary to smooth the surface. Recurrences are rare in these eyes. In contrast, some eyes (often with major peripheral vascularization) are left with deep defects in Bowman's layer and superficial stroma after difficult mechanical removal of nodules. In these eyes, multiple masking/laser ablation procedures are mandatory to acquire a homogenous surface. In our experience, the required laser ablation depth is significantly greater and the best-corrected visual acuity to be expected is reduced in contrast to the eyes with easy removal of the nodules. In these eyes recurrences seem to occur more frequently after treatment. Of 35 eyes documented to have Salzmann's nodular degeneration during the last 15 years in our department, 22 needed PTK treatment. Visual acuity increased from 0.4 to 0.7 on average. As a routine, laser ablation should be combined with previous conventional removal of nodules and excessive pannus tissue. By doing so, lamellar and penetrating keratoplasty techniques are hardly ever required in those eyes.

Purpose To report cultivated epithelial transplantation in 2 patients with vernal keratoconjunctivitis (VKC) with severe ocular surface disease. Methods Two patients initially diagnosed with burnt-out VKC presented with bilateral photophobia, decreased vision, and corneal neovascularization. The first patient underwent living-related conjunctival-limbal allograft in the left eye and cultivated limbal epithelial cell allotransplant in the right. The second patient underwent unsuccessful amniotic membrane transplantation (AMT) followed by autologous cultivated limbal epithelial cell transplantation in the worse eye. Results Both patients had onset of VKC in the first decade. Surgical intervention in both led to marked amelioration in symptoms and improvement in vision. In patient 1, vision improved from 20/800 (both eyes) to 20/30 in the right and 20/100 in the left eye at a follow-up of 34 months. In patient 2, it improved from 20/400 to 20/50 after the second procedure, 25 months postoperatively. Histopathology of the excised pannus revealed fibrosis and mononuclear cell infiltrates in all 3 eyes. Conclusions Severe ocular surface disease may occur in persistent VKC, leading to marked visual loss. AMT alone may be insufficient to restore the ocular surface, and limbal epithelial cell transplantation is warranted.

Purpose. To report the features of a syndrome of endothelial failure and band-shaped keratopathy in an infant with corpus callosum agenesis. Methods. The clinical and histopathologic features of an infant presenting with bilateral corneal clouding and corpus callosum agenesis are reported. The patient underwent bilateral penetrating keratoplasty at ages 28 months and 4 years. Light and electron microscopy were used to characterize the structural changes. Results. The epithelium was thin and degenerate. Bowman's membrane contained spherical aggregates that were present also within a connective tissue pannus. The midstroma was normal, but there were floral and rope-like aggregations of collagen in the pre-Descemet's membrane region. Under electron microscopy, the spherules formed target-shaped lesions with a central focus of alternating electron-dense and lucent material. Numerous microfilaments in the pannus and anterior stroma labeled with fibrillin-1 antibody. Microfilaments within fibroblasts were stained with vimentin antibody. Posteriorly, the endothelium was mainly absent and Descemet's membrane showed a fetal layer and a posterior collagenous layer. Conclusion. Corneal appearances in this patient were in keeping with those of congenital hereditary endothelial corneal dystrophy. However, there was no family history and neither parent showed a clinical endothelial abnormality. The presence of fetal, banded material in Descemet's membrane suggested that endothelial loss began at or near the time of birth. The band keratopathy was regarded as a secondary change. The association with corpus callosum agenesis does not appear to have been described previously.

Purpose. To report the unusual occurrence of bilateral, superficial, corneal fibrosis with pannus formation in a young woman with homocystinuria, and to describe the light and transmission electron microscopic findings ofthese deposits. Methods. Excision of the corneal lesion and amniotic membrane transplantation was performed in both eyes. The excised material was studied using light and transmission electron microscopy. Results. Whitish, elevated, irregular masses with superficial vascularization in the peripheral cornea were noted in both eyes. Histopathologic evaluation of the excised corneal tissue revealed variable epithelial thickness with melanin pigment in the basal layer. A fibrovascular pannus, fibrosis and disruption of the Bowman's layer, and fibrosis of anterior stroma were evident. Transmission electron microscopy revealed numerous empty intracytoplasmic vacuoles in the corneal epithelial cells and intracytoplasmic inclusions containing fibrillogranular material in the cytoplasm of keratocytes. Conclusion. We report the unusual association of corneal fibrosis and scarring in a young woman with homocystinuria. The deposits revealed the presence of membrane-bound inclusions containing fibrillogranular material in the corneal epithelium and keratocytes. Although the etiology of these deposits is not clear, the condition improved following excision of these lesions and amniotic membrane transplantation.

PURPOSE To evaluate the histopathological features of corneal graft failures over time. METHODS A single-center retrospective analysis was performed on corneal specimens diagnosed as corneal graft failure retrieved from The Henry C. Witelson Ophthalmic Pathology Laboratory and Registry (Montreal, Canada) over a 9-year period. The corneal buttons were divided into 3 different groups according to the time between the diagnosis of corneal graft failure and regraft. Corneal specimens obtained during keratoplasty were subjected to hematoxylin and eosin and periodic acid-Schiff. Five different histopathological findings were evaluated in each specimen. RESULTS Overall, the most common histopathological finding was endothelial decompensation (97.2%). Subepithelial pannus (38.9%), vessels in the corneal stroma (11.1%), and anterior synechiae (2.8%) were the other present findings. The inflammatory reaction was considered discrete in 83.3% of the cases. The only significant histopathological finding correlated with time was the presence of vessels in the corneal stroma (P = 0.0092). CONCLUSIONS Corneal neovascularization, represented by the presence of vessels in the corneal stroma, was the only histopathological finding correlated with time. Because it is a known factor of poor prognosis, our findings strongly support that early regraft has higher chances of success.

PURPOSE To report 2 cases of severe keratopathy in patients with AIDS with delayed diagnosis of lagophthalmos. METHODS Observational case report. RESULTS The first patient presented with a corneal abscess attributed to old trauma. He responded poorly to topical treatment and suffered corneal penetration. Penetrating keratoplasty was performed, but persistent epithelial defects appeared. Finally, occult lagophthalmos was discovered. Topical ocular lubrication, eye occlusion, and lateral tarsorrhaphy were insufficient, and the graft became conjunctivalized. The second patient had corneal opacity and severe pannus in his right eye and mild punctate keratopathy in his left eye. The left cornea worsened despite treatment with lubricants. In an examination 2 weeks later, we detected a subtle lagophthalmos, which was complicated by upper eyelid retraction in the right eye. A bilateral upper blepharotomy improved the keratopathy. CONCLUSIONS Patients with AIDS with severe weight loss can present with lagophthalmos because of adipose and muscular atrophy in the so-called wasting syndrome. Lagophthalmos in patients with AIDS can be difficult to detect. Clinically significant lagophthalmos is associated with ocular surface lesions in patients with AIDS with wasting syndrome.

Purpose: To report the ultrastructure of superficial hypertrophic dendriform epitheliopathy (SHDE). Method: Two epithelial and two penetrating keratoplasty specimens from 1 patient were examined by electron microscopy. Tissue was processed for light and transmission microscopy. Results: Striking intraepithelial aggregates corresponded to zones affected clinically. These stained heavily with toluidine blue and were composed ultrastructurally of electron-dense, microfibillar aggregates. The thin and degenerate epithelium contained a dense cytoplasm, lucent spaces, numerous microfilaments, and glycogen granules. Basal cells showed infrequent hemidesmosomes. Basement membrane contained long-spacing collagen and Bowman's layer was replaced by a collagenous pannus, separated from the epithelium by large lucent spaces. Keratocytes within the pannus were degenerate, while collagen fibres were sparse and intermixed with microfilaments and long-spacing collagen. Large quantities of proteoglycans were present in pannus and stroma. Descemet's membrane was arranged in multiple lamellae containing basement membrane material, long-spacing collagen and microfilaments. Conclusions: SHDE is a distinct syndrome that occurs after keratoplasty in patients with tear dysfunction. It is speculated that it represents an aberrant form of keratinisation due to exposure and poor wetting in a denervated cornea. Chronic epithelial change leads to secondary reactive changes in the stroma.

Purpose. To report the clinical, histologic, ultrastructural, and immunohistochemical features of congenital hereditary endothelial dystrophy (CHED) associated with subepithelial amyloid deposits. Methods. The clinical features of seven patients and histologic characteristics of eight corneal buttons were evaluated. The corneal specimens included five cases with histologic features of CHED associated with subepithelial amyloid. The remaining three corneal buttons of CHED without amyloid were obtained from the fellow eye of an affected patient and from siblings of two affected patients. Light microscopic studies were performed on sections stained with hematoxylin and eosin, periodic acid Schiff stain, and Congo red stain with and without permanganate bleach. Immunohistochemistry with an antibody to the amyloid AA protein and lambda and kappa light chains was done on all specimens. Electron microscopy was performed on three corneal specimens. The cases were followed for 1-9 years. Results. The notable clinical findings included decreased vision, history of parental consanguinity (4/7 cases), and affected siblings (5/7 cases). Examination revealed nystagmus (5/7 cases) and bilateral ground-glass corneas in all patients. In addition, central subepithelial whitish opacities were noted in patients with CHED and amyloid. Three patients had associated congenital glaucoma. The patients underwent penetrating keratoplasty at a mean age of 10 years. Histologically, five corneal buttons of CHED revealed varying degrees of subepithelial amyloid deposits associated with a subepithelial fibrous pannus. Immunohistochemically, the deposits were nonreactive to anti-amyloid A antibody but were immunoreactive with an antibody to lambda light chains in two cases. Electron microscopy confirmed the presence of subepithelial amyloid. Thickening of Descemet's membrane and attenuation of corneal endothelial cells, noted in all cases, was consistent with features of CHED. The corneal buttons from the fellow eye and the siblings showed histologic features of CHED, with a subepithelial fibrous pannus without amyloid deposits. Spheroidal degeneration was noted in two corneal specimens. To date, no recurrence of the amyloid deposits has been seen in the grafts. Conclusions. This study demonstrates that subepithelial amyloidosis may be rarely associated with a recessive form of congenital hereditary endothelial dystrophy. The clinical, histologic, and immunohistochemical features suggest a secondary form of amyloidosis.

A 22-year-old female college student from the southwestern United States was first seen with progressive fluffy white growths over both corneas nasally and a history of chronic allergies and extensive sun, wind, and chlorine exposure as a competitive swimmer. The lesions were superficial, elevated, crescent-shaped, vascularized, and extended from the limbal conjunctiva onto the peripheral cornea nasally. The lesions were composed of an unencapsulated thick fibrovascular pannus with numerous fibrocytes, chronic inflammatory cells and mast cells, and abundant linear and wavy elastinophilic profiles, but no adipose tissue. Ultrastructurally, the elastinophilic structures were immature elastic fibers arranged in globules and bundles within a thick collagenous matrix. No mature elastic fibers were found. A few areas of elastotic degeneration were also found. This lesion resembled elastofibromas that have been reported more commonly in the subcapsular region and only once in the ocular region. Previous reports debated whether the elastic material in elastofibromas is derived from excessive production of elastic fibers by activated fibrocytes or from elastotic degeneration of collagen. In our case, both processes occur and are presumed to result from excessive ultraviolet radiation, wind and chlorine exposure, and perhaps, chronic inflammation; features that have been ascribed to the pathogenesis of pingueculae and pterygia.

Corneal lesions in aniridia include peripheral pannus and epithelial abnormalities that may advance centrally, resulting in the need for penetrating keratoplasty. Three patients with aniridia who underwent repeated corneal surgical procedures (one keratectomy and six penetrating keratoplasties) are described herein. A clinicopathological correlation was performed. In all three patients there was evidence of recurrent pannus and epitheliopathy on histopathological examination, which correlates with the clinical findings. These findings suggest that the pathophysiology of recurrent aniridia keratopathy may be related to a primary abnormality in the stem cells of the recipient corneal limbus. Aniridic pannus and epitheliopathy recur in grafts after penetrating keratoplasty and threaten the transplanted cornea. The risk of recurrent keratopathy should be considered when recommending a surgical procedure to patients with aniridia.

Fifteen eyes in 12 patients with Salzmann's nodular corneal degeneration developed symptoms of recurrent erosion, decreased vision, or both. A history or evidence of ocular surface disease was present in 14 of 15 eyes. Removal of the nodule and accompanying pannus or corneal epithelial basement membrane degeneration, provided symptomatic improvement in all patients.

To determine the diagnostic usefulness of routine staining of corneal buttons with alcian blue, we evaluated 150 consecutive corneal specimens with hematoxylin and eosin and alcian blue stains. Overall, 67% of specimens demonstrated deposition of acid mucopolysaccharide. More specifically, positive alcian blue staining was observed in 88% of specimens with pannus, 83% of specimens with stromal downgrowth, 71% of specimens with stromal scarring, and 67% of specimens with interstitial keratitis. In 80% of these cases, the positive alcian blue stain correlated to pathology noted on hematoxylin and eosin sections. In 20% of cases, we could not explain the reason for the presence of alcian blue staining. Except for macular dystrophy of the cornea, the presence, strength, and location of staining did not provide useful information in terms of making a specific clinical diagnosis. Consequently, alcian blue should be used only in those settings in which the pathologist needs to document or confirm the abnormal presence or absence of acid mucopolysaccharide deposition.