Stromal demarcation line induced by corneal cross-linking in eyes with keratoconus and nonkeratoconic asymmetric topography.

PURPOSE: To evaluate stromal demarcation lines following corneal cross-linking (CXL) using anterior segment optical coherence tomography in patients with keratoconus and nonkeratoconic asymmetric topography. METHODS: Fifth-nine eyes of 59 patients were enrolled in a retrospective comparative case series, of which 19 eyes had keratoconus and 40 eyes had asymmetric topography. Eyes with asymmetric topography were treated in preparation for photorefractive keratectomy. One month after CXL, a stromal demarcation line was evaluated at 5 standardized corneal points using anterior segment optical coherence tomography. RESULTS: Mean stromal demarcation line depths were measured at 5 points on the cornea, namely, centrally, 3.0 mm temporally, 1.5 mm temporally, 3.0 mm nasally, and 1.5 mm nasally. For the keratoconus group, the values were 178 ± 47, 123 ± 15, 152 ± 47, 125 ± 23, and 160 ± 43 µm, respectively. For the asymmetric corneal topography group (without keratoconus), they were 305 ± 64, 235 ± 57, 294 ± 50, 214 ± 54, and 285 ± 58 µm, respectively. There was no correlation between central corneal pachymetry and stromal demarcation line depth in all 5 measured corneal points in both groups. CONCLUSIONS: CXL treatment profiles are similar in keratoconic and nonkeratoconic eyes with asymmetric topography.

Recurrent ectasia in corneal grafts and outcomes of repeat keratoplasty for keratoconus.

AIM: To analyse cases of recurrent ectasia in donor corneas after penetrating keratoplasty (PK) for keratoconus. METHODS: Data on 25 patients (36 eyes) with recurrent ectasia were retrospectively analysed in this study. The main outcome measures were time to development of recurrent ectasia after first PK for keratoconus, change in keratometric sphere and astigmatism between final suture removal and development of recurrent ectasia, status of regrafts for recurrent ectasia, and histopathology of grafts excised for recurrent ectasia. RESULTS: The age at first PK was 32.6 (SD 8.5) years, and ectasia developed 21.9 (7.0) years after PK. The mean keratometric sphere and cylinder increased by 4.2 D and 3.0 D, respectively, between final suture removal and diagnosis of recurrent ectasia. Ectasia was often preceded by thinning without bulging of the recipient stroma at the graft-host junction. Fifteen eyes (13 patients) were regrafted for recurrent ectasia, and histopathology of the excised grafts showed changes characteristic of keratoconus in the donor tissue in all cases. Two regrafts (two eyes of one patient) developed ectasia again, with one eye requiring a third PK to improve vision. CONCLUSIONS: Recurrent ectasia was diagnosed on average two decades after PK. Ectatic changes were often bilateral and occasionally recurred after regrafting, suggesting that host cellular and/or biochemical factors may be responsible. Repeat PK for recurrent ectasia is successful in the intermediate term.

Free floating cyst in anterior chamber after cataract surgery.

We describe a free-floating cyst in the anterior chamber after cataract surgery in a 73-year-old woman who underwent uneventful phacoemulsification in her right eye (OD). The best-corrected visual acuity one week after surgery was 20/20 OD; however, six weeks later, she noted the onset of intermittent "shadows" in this eye whenever she changed head position. Slit lamp examination showed a round, free-floating, clear cyst (3-4 mm in diameter) that traversed the central visual axis during eye movement. The cyst was removed through a limbal incision, by expressing it gently out of the eye with viscoelastic injection into the anterior chamber. On pathological examination the inner wall of the cyst was lined with non-keratinized squamous epithelium, typical of ocular surface cells.

Hereditary hemorrhagic telangiectasia diagnosed by the ophthalmologist.

PURPOSE: To show the clinical features of a case of hereditary hemorrhagic telangiectasia in which the diagnosis was prompted by ophthalmologic examination. METHODS: A retrospective case review of a 56-year-old East Indian woman whose presentation to the eye clinic with a history of bloody tears and conjunctival vascular malformations prompted a systemic evaluation that resulted in the diagnosis of hereditary hemorrhagic telangiectasia. RESULTS: The diagnosis of hereditary hemorrhagic telangiectasia was eventually confirmed by gastrointestinal endoscopy and otorhinolaryngologic examination. CONCLUSION: Although hereditary hemorrhagic telangiectasia is typically diagnosed on the basis of gastrointestinal and otorhinolaryngologic history and examination, the ophthalmologic features of this case were striking enough to arouse suspicion of this disease.

Small, overlapping tectonic keratoplasty involving graft-host junction of penetrating keratoplasty.

PURPOSE: To report the indications for and postoperative course of small tectonic keratoplasties overlapping (and involving) the graft-host junction of preexisting penetrating keratoplasties. METHODS: A retrospective study of 15 consecutive eyes (15 patients) with small tectonic keratoplasties overlapping the graft-host junction of preexisting penetrating keratoplasties. RESULTS: After tectonic keratoplasty, follow-up times ranged from 5 months to 20 years (mean, 69 months). Clinical indications included sterile corneal ulceration (seven cases), bacterial keratitis (six cases), and fungal keratitis (two cases). In the six cases with bacterial keratitis, five were suture abscesses, with four resulting in wound dehiscence. Ten tectonic grafts were lamellar keratoplasties, and five were penetrating keratoplasties. Postoperative best-corrected visual acuities were unchanged from preoperative levels in every patient. After tectonic grafting, the mean +/- SD change in keratometric astigmatism in the parent penetrating keratoplasty was 1.75 +/- 1.50 diopters. The astigmatism increased in 10 cases, decreased in three, and remained unchanged in two. There was no case of recurrent ulceration or wound dehiscence in or around the tectonic grafts. The surgery did not result in new glaucoma or worsening of preexisting glaucoma. CONCLUSIONS: In the treatment of infectious or ulcerative foci at or near the graft-host junction of penetrating keratoplasties, a small extirpative, tectonic graft over the diseased junction appears to be a safe and effective alternative to either repeating the original penetrating keratoplasty or performing an oversize transplant.

Lamellar corneal patch grafts in the management of corneal melting.

PURPOSE: To evaluate the clinical indications and results of reconstructive (tectonic) lamellar keratoplasty in corneal melting. METHODS: A nonrandomized, uncontrolled retrospective case series of 64 consecutive patients (80 eyes) who underwent lamellar keratoplasty for corneal melting at our institution over a 17-year period. We reviewed the (a) clinical indications, (b) visual acuities, (c) postoperative corneal clarity, and (d) post-operative complications. Comparisons in visual acuity were made between central and peripheral corneal melts. The statistical influence of patient age, diagnosis, and corneal graft size on pre- and postoperative visual acuity values also was studied. RESULTS: Although reconstructive lamellar keratoplasty for active corneal melting was effective in saving the integrity of the globes in all but four patients, the postoperative visual acuity remained poor in the majority of cases because of the often devastating nature of the underlying ocular diseases. Only 14 patients had best postoperative visual acuities of 20/100 or better. Repeated lamellar keratoplasties were necessitated by corneal opacification, infection, or progressive postoperative corneal dissolution in 14 cases. Subsequent vision-restoring surgeries, consisting of penetrating keratoplasties or cataract extractions, were done in 11 eyes with modest improvement of visual acuity. Postoperative visual acuity was significantly better in peripheral corneal melts than in central melts (p = 0.004). CONCLUSION: Lamellar keratoplasty is an effective method of restoring the integrity of the eye ravaged by corneal melting. It is less invasive and consequently safer than penetrating keratoplasty in actively inflamed and unstable eyes. The primary purpose for this surgery is to salvage the integrity of the globe during the acute phase of disease and not so much to achieve visual improvement per se. It allows time for systemic immunosuppression to take effect and for the eye to quiet down before possible future vision-restoring surgery.

Conjunctival mucoepidermoid carcinoma in a young HIV-infected man.

PURPOSE: To report a case of conjunctival mucoepidermoid carcinoma occurring in a long-standing pterygium in a 33-year-old Cambodian man infected with the human immunodeficiency virus (HIV). METHODS: Review of clinical history and histopathologic findings. RESULTS: A pterygium that was present for 8 years suddenly became highly inflamed and underwent rapid growth. After the initial diagnostic conjunctival and corneal biopsy showed mucoepidermoid carcinoma, subsequent additional deep excisions of the adjacent sclera and cornea were necessary to completely excise the tumor. Cytokeratin and mucicarmine stains were used to confirm the pathologic diagnosis of mucoepidermoid carcinoma. CONCLUSIONS: Unique features of this case include the extremely young age of the patient (perhaps rendered susceptible by his HIV infection), the tumor masquerading as a pterygium, and the use of a hybrid lamellar and full-thickness corneoscleral resection requiring a complementary graft. Seventeen months after the resection, the patient is free of tumor; this was histopathologically confirmed with multiple random conjunctival biopsies.

Central lamellar keratoplasty for optical indications.

PURPOSE: This study aims to evaluate the results of lamellar keratoplasty (LKP) for optical (nontectonic) indications over the past 19 years at our institution, noting the advantages and pitfalls of the procedure. METHODS: The study is a retrospective review of 52 central LKPs in 37 patients. Snellen visual acuity, preoperative clinical indications, and postoperative status of the cornea (donor graft, graft-host interface, and recipient cornea) were assessed. RESULTS: Postoperative follow-up ranged from 3 months to 18 years (median, 3 years). In descending order of frequency, corneal dystrophies, aniridic keratopathy, corneal scars, and keratoconus were the most common indications for surgery. After surgery, 38% of the eyes were able to achieve 20/50 or better visual acuity. The two most common causes of poor visual acuity were (1) opacification and/or blood vessel growth in the graft-host interface or on the graft surface and (2) high astigmatism. Persistent epithelial defects occurred in 21% of the eyes after LKP. CONCLUSION: Although LKP provides a safer alternative to penetrating keratoplasty, it is limited by vision-reducing graft-host interface problems, astigmatism, and difficult surgical technique. We postulate that the current results of LKP may be improved by (1) removing as much recipient corneal stroma as possible (e.g., dissecting down to Descemet's membrane) or, alternatively, using an automated microkeratome and (2) raising the currently used qualitative eyebank standards for accepting LKP donor tissue.

The utility of culturing corneal ulcers in a tertiary referral center versus a general ophthalmology clinic.

OBJECTIVE: The purpose of the study is to compare the utility of culturing corneal ulcers in a tertiary referral clinic and a general ophthalmology clinic. DESIGN: A retrospective review of medical and microbiologic records was performed. PARTICIPANTS: One hundred fifty-seven patients with corneal ulcers were included in the study. Eighty-two ulcers were treated in the referral clinic and 75 ulcers were treated in the general ophthalmology clinic. MAIN OUTCOME MEASURES: The authors determined the percentage of corneal ulcers in each clinical setting that failed to respond to empiric therapy and required a culture-directed change in treatment. RESULTS: One hundred fifty-seven ulcers were included. Eight (10%) of the 82 patients treated in the Cornea Clinic had treatment altered based on culture and sensitivity results. All 75 patients in the general clinic responded to empiric antibiotics, such that culture data never were required for modification of therapy (0%, P = 0.007). In contrast to patients treated in the Cornea Clinic, patients treated in the general clinic had smaller, more peripheral ulcers, shorter duration of symptoms, and fewer risk factors for corneal ulceration other than contact lens wear. CONCLUSIONS: Cornea specialists, who are referred the most severe cases, should consider culturing most corneal ulcers. However, it appears reasonable for general ophthalmologists to use culturing more judiciously. Patients with significant corneal ulcers should be cultured regardless of the clinic to which they present. However, small, peripheral ulcers respond extremely well to current, broad-spectrum antibiotics. Close follow-up is mandatory to discover the rare patient who will not respond to empiric therapy.

Non-tuberculous mycobacterial keratitis: a study of 22 cases.

AIM: To investigate causes and clinical findings of non-tuberculous mycobacterial keratitis, and to study its response to topical antibiotic therapy and surgical extirpative keratectomy. METHOD: A single centre, retrospective review of 22 patients with non-tuberculous mycobacterial keratitis seen in a 3 year period. Laboratory diagnoses were established with Ziehl-Nielsen acid fast staining and Löwenstein-Jensen cultures. RESULTS: In 20 patients (91%), there was an antecedent history of foreign body eye trauma (18 patients) or elective surgery (two patients). There were 19 cases of Mycobacterium chelonei, and three of M fortuitum. Clinical signs included epithelial defects, satellite or ring stromal infiltrates, crystalline keratopathy, and hypopyon. For topical antibiotic therapy, 20 patients received amikacin, while one patient received rifampin and another received ciprofloxacin, each in accordance with the results of the in vitro drug sensitivities. An extirpative keratectomy was performed in 15 cases; four of these cases additionally required a temporary conjunctival flap in order to finally eradicate the infection. At the end of the follow up period (median 18 months; range 3 months to 3 years) all eyes were stable and free of infection, with 19 (86%) having final visual acuities of 20/200 or better. CONCLUSION: Early clinical recognition and prompt laboratory diagnosis, together with aggressive topical antibiotic therapy and early keratectomy, may shorten morbidity and improve the clinical outcome of non-tuberculous mycobacterial keratitis.

Galvanotropic and galvanotaxic responses of corneal endothelial cells.

The effects of weak electric fields (E-fields) on cultured rabbit corneal endothelial cells were studied. The cells responded to steady E-fields (2-6 V/cm) by elongating their somata 90 degrees to the field (galvanotropism) and by migrating (galvanotaxis) towards the anode. During these directional movements, pseudopodia and ruffled membranes formed preferentially on the anodal side of the cells, while they retracted on the cathodal side. Fluorescent labelling for actin showed many stress fibers aligned parallel to the long axes of the elongated cells and few aligned toward the anodal direction. Fluorescent labelling for vinculin showed the abundance of cell-to-substratum adhesion foci at the termini of the stress fibers. Galvanotropic and galvanotaxic cellular movements were inhibited by cytochalasin D (0.1-0.5 microgram/mL) and the calmodulin antagonist, W-7 (80 mumol/L). These results suggest that E-field induced directional movements of corneal endothelial cells constitute a calmodulin-dependent, active (not passive) process.

Immune-mediated subepithelial blistering diseases of mucous membranes. Pure ocular cicatricial pemphigoid is a unique clinical and immunopathological entity distinct from bullous pemphigoid and other subsets identified by antigenic specificity of autoantibodies.

BACKGROUND AND DESIGN: There is much confusion in the clinical classification of immune-mediated subepithelial blistering diseases of mucous membranes. We conducted a 6-year comprehensive study to better classify this heterogeneous disease group. Indirect immunofluorescence was performed on a salt-split-skin substrate to detect circulating antibasement membrane antibodies (n = 47). Serologic reactivity against cultured keratinocyte antigens was examined by immunoblots (n = 38) and immunoprecipitation (n = 15). The results were correlated with the clinical features and direct immunofluorescence data of the entire patient group (n = 87) without preassignment of clinical diagnoses. chi 2 Statistical analyses compared these results with those of the classic bullous pemphigoid group (n = 36). RESULTS: When compared with the bullous pemphigoid patients, a subset of patients with combined oral mucosal and skin lesions demonstrated marked similarity in direct and indirect immunofluorescence findings and in serologic reactivity to bullous pemphigoid antigens. By contrast, a subset of patients with only ocular lesions exhibited significantly lower in vivo deposits of IgG and C3, higher deposits of fibrin, virtual absence of circulating antibodies, and negative serologic reactivity to bullous pemphigoid antigens. CONCLUSIONS: Ocular patients without skin or mouth lesions, in particular those with negative indirect immunofluorescence, should be distinctively classified as ocular cicatricial pemphigoid, a unique clinical and immunopathologic entity. Patients with mucous membrane involvement who also demonstrate skin lesions and antibodies to the root of salt-split-skin substrate should be classified as anti-BP Ag mucosal pemphigoid, even though they may exhibit severe oral and/or ocular diseases. The remaining mucous membrane patients are heterogeneous. Some can be classified on the basis of autoantibodies to other basement membrane determinants, or if serum autoantibody negative, on the basis of clinical features (ie, pure oral mucosal pemphigoid or overlapping mucosal involvement).

Prognosis for penetrating keratoplasty in iridocorneal endothelial syndrome.

BACKGROUND: Iridocorneal endothelial syndrome is characterized by the proliferation and spreading of an abnormal corneal endothelial membrane across the iridocorneal angle and iris surface, resulting in iridocorneal adhesions, glaucoma, pupillary distortion, varying degrees of iris atrophy, and occasionally corneal decomposition with edema. These changes may possibly affect the long-term prognosis of penetrating keratoplasty in an adverse fashion. METHODS: We reviewed the clinical course of 12 consecutive eyes (12 patients) which underwent penetrating keratoplasty for corneal edema associated with the iridocorneal endothelial syndrome (mean postoperative follow up = 30 months). RESULTS: The grafts remained clear in 10 patients (83%) and the visual acuity was 20/40 or better in nine patients (75%). The endothelial cell losses averaged 13% at 6 months and 17% at 1 year after surgery. Simultaneous extracapsular cataract extraction and posterior chamber lens implantation at the time of keratoplasty posed no measurable compromise to the overall postoperative prognosis. Causes of poor visual acuity after surgery included glaucoma and graft failure (immune and nonimmune). CONCLUSIONS: The prognosis of penetrating keratoplasty in the iridocorneal endothelial syndrome appears to be very favorable in the majority of eyes.

Secondary localized amyloidosis in interstitial keratitis. Clinicopathologic findings.

Cases of secondary localized corneal amyloidosis have been described in various corneal and ocular inflammations but are believed to occur uncommonly. The authors examined histopathologic specimens from 33 consecutive patients with interstitial keratitis who underwent penetrating keratoplasty for visual rehabilitation. In 11 cases (33%), multiple fusiform deposits of amyloid were identified and confirmed in middle and deep corneal stroma using histochemical staining. Characteristic electron microscopic findings were present in two cases. These results indicate that secondary localized corneal amyloidosis occurs frequently in interstitial keratitis and displays a distinct pattern of deposition.

Effects of steady electric fields on human retinal pigment epithelial cell orientation and migration in culture.

Low-level, steady electric fields of 6-10 volts/cm stimulated directional orientation and translocation of cultured human retinal pigment epithelial cells. The orientative movements (galvanotropism) consisted of somatic elongation of the cells into spindle shapes, followed by pivotal alignment orthogonal to the field. The anodal edges of the cells underwent retraction of their plasmalemmal extensions, while the cathode edges and the longitudinal ends developed lamellipodia and ruffled membranes. These tropic movements were followed by a translocational movement (galvanotaxis) of the cells towards the cathode. Staining of these migrating cells for actin showed the accumulation of stress fibers at the leading (cathodal) edge, as well as at the longitudinal ends of the elongated somata. These results suggest that endogenous, biologically-generated electric fields (eg., injury currents) may play a role in the guidance and migration of retinal pigment epithelial cells after retinal injury.

FGF promotes corneal stromal fibroblast motility.

It is well-known that growth factors accelerate wound healing by stimulating mitosis. Growth factors may also directly stimulate the motility of individual cells. We employed two different experimental methods to determine if fibroblast growth factor (FGF) enhances the individual motility of corneal stromal fibroblasts (independent of mitogenic effects). The effects of FGF on the motility of tissue-cultured rabbit corneal stromal fibroblasts were investigated in a modified Boyden chamber and by the agarose drop motility assay. Both assays showed a significant enhancement of stromal fibroblast motility by FGF at 100 ng/ml. It appears, therefore, that FGF may promote corneal stromal wound healing not only by increased cellular proliferation, but also by increased cellular motility.

Ocular cicatricial pemphigoid occurring as a sequela of Stevens-Johnson syndrome.

Ocular cicatricial pemphigoid is a chronic scarring inflammation of the ocular mucosae that can lead to blindness. Although cicatricial pemphigoid has been classified clinically, histopathologically, and immunopathologically, no definite initiating factor or precipitating factor has been identified. In this report, we describe five cases of ocular cicatricial pemphigoid that developed following an acute episode of severe ocular inflammatory injury secondary to Stevens-Johnson syndrome. The time lag between the onset of Stevens-Johnson syndrome and cicatricial pemphigoid ranged from a few months to 31 years. All five patients had linear immune deposits characteristic of cicatricial pemphigoid along the basement membrane zone of mucosal biopsy specimens as detected by either direct immunofluorescence microscopy or direct immunoperoxidase staining. In two patients whose serum was tested, a Western blot assay taken of keratinocyte antigens that had undergone electrophoresis reacted with the serum and identified a 120-kd epidermal antigen detected by the IgG class antibodies. All five patients were treated with systemic immunosuppressive therapy for cicatricial pemphigoid, and we obtained objective responses. Severe ocular mucosal injury such as that which occurs in Stevens-Johnson syndrome may be a precipitating factor in the development of ocular cicatricial pemphigoid.

Implantation of Kelman-style, open-loop anterior chamber lenses during keratoplasty for aphakic and pseudophakic bullous keratopathy. A comparison with iris-sutured posterior chamber lenses.

The clinical and specular microscopic results of 40 cases (39 patients) of penetrating keratoplasty during which a Kelman-style anterior chamber intraocular lens was implanted were reviewed retrospectively. Thirty-one pseudophakic eyes received an intraocular lens exchange and nine aphakic eyes received a secondary intraocular lens. Postoperative follow-up averaged 24.5 months (range, 3 to 51 months). At 1, 2, and 3 years after keratoplasty, 39.3%, 63.2%, and 63.6% of eyes, respectively, had visual acuities of 20/40 or better. Ninety-five percent of the grafts remained clear. Causes of poor postoperative visual acuity included cystoid macular edema (32.5%), new glaucoma (22.5%), and age-related macular degeneration (10.0%). Other causes were endothelial rejection leading to graft failure, corneal ulceration, and retinal detachment. Corneal endothelial cell loss by specular microscopy was 11.5% at 1 years, 21.3% at 2 years, and 25.0% at 3 years. These results were compared with cell loss associated with iris-sutured posterior chamber lenses in penetrating keratoplasty. Visual outcomes and complication rates were similar between these two methods; however, the endothelial attrition at 1 and 2 years for the sutured posterior chamber lens was greater than that of the Kelman anterior chamber lens.