Peripheral Corneal Research Articles

Directed Differentiation of Human Embryonic Stem Cells to Neural Crest Stem Cells, Functional Peripheral Neurons, and Corneal Keratocytes.

Neural crest stem cells (NCSCs) are a transient and multipotent cell population giving rise to various cell types with clinical importance. Isolation of human NCSCs is extremely challenging that limits our knowledge about neural crest development and application. Here, a defined protocol to efficiently direct human embryonic stem cells (hESCs) to NCSCs and multiple neural crest lineages is presented. A unique combination of small molecule inhibitors and growth factors is employed to generate NCSCs from hESCs through a neuroectoderm stage. The self-renewal and multipotent capacities of hESC-derived NCSCs are assessed subsequently. In the feeder-free system, hESC-derived NCSCs (P75+ /HNK1+ /AP2α+ /PAX6- ) in high purity are efficiently generated following neuroectodermal restriction. They can be propagated and differentiated toward multiple neural crest lineages in vitro, such as functional peripheral neurons (β-tubulin III+ /peripherin+ ), mesenchymal stem cells (CD73+ CD90+ CD105+ ), and corneal keratocytes (keratocan+ ). The in vivo developmental potential of hESC-derived NCSCs is confirmed using zebrafish embryos. This report is the first demonstration of efficient differentiation of hESCs into corneal keratocytes as a monolayer in a feeder-free system. Considering the high efficacy of NCSC generation, this new method will be a useful tool for future clinical organ repair and regeneration, such as peripheral nerve regeneration and corneal repair.

Corneal stroma lenticule combined with amniotic membrane transplantation for fungal corneal ulcer

Objective To observe the clinical effect of corneal stroma lenticule combined with amniotic membrane transplantation for fungal corneal ulcer. Methods A retrospective study was performed. The data of 14 eyes of 14 patients with fungal corneal ulcer was collected from January 2015 to December 2015. All patients had histories of plant ocular trauma. Corneal stroma lenticule combined with amniotic membrane transplantation were performed for fungal corneal ulcer. Corneal stroma lenticules were taken from myopia patients who underwent femtosecond laser-assisted small incision lenticule extraction. For all these donors, informed consent was obtained and blood-borne diseases tests were performed. Extracted corneal stroma lenticules were placed into sterilized pure glycerin in a refrigerator at -80 ℃. Results Inflammation of fungal corneal ulcer disappeared and cornea ulcer well healed in all the 14 cases. Thirteen patients underwent 1 operation and 1 patient underwent 2 operations until corneal ulcers healed. Patients with peripheral corneal ulcer had better vision after ulcer healed. Conclusion Corneal stroma lenticule combined with amniotic membrane transplantation for fungal corneal ulcer is safe and effective. Key words: Corneal ulcer; Lenticule, corneal stroma; Transplantation, amniotic membrane

Toric Intraocular Lenses Versus Peripheral Corneal Relaxing Incisions for Astigmatism Between 0.75 and 2.5 Diopters During Cataract Surgery

To compare the outcomes after toric intraocular lens (tIOL) or peripheral corneal relaxing incisions (PCRI) for keratometric astigmatism (KA) between 0.75 and 2.5 diopters (D) during cataract surgery. Prospective randomized clinical trial. Eighty eyes (80 participants) received either tIOL or PCRI and were assessed preoperatively, 1, 3, 6, and 12months postoperatively. Uncorrected (UCDVA) and best-corrected distance logMAR visual acuity (BCDVA) at 12months. Uncorrected near visual acuity (UCNVA), manifest refraction, KA and mean keratometry (KM), corneal aberrometry, tIOL rotation, and quality-of-life questionnaire. Comparing tIOLs vs PCRIs, there was no significant difference in the UCDVA, BCDVA, and UCNVA. At 12months, 61% vs 53% had UDCVA of 20/25 or better, 100% vs 76% gained ≥1 lines, and 59% vs 43% were within ±0.13 D spherical equivalent. In the PCRI group, anterior KA decreased at 1month and remained stable thereafter; there was a nonsignificant trend toward a flatter posterior KA and steeper posterior KM and the total corneal Z2-2 was low at 1 and 12months. Over 12months, there were changes in posterior corneal tilt, coma, and hexafoil in the PCRI group. The mean rotation of the tIOLs at 12months was 1.8 ± 1.4 degrees. tIOL patients were happier and were glad to use the nonprescription sunglasses. There was no difference in visual acuity, although more tIOL patients gained ≥1 line and were within ±0.13 D. After PCRIs, the anterior KA decreased in the early postoperative period and remainedstable thereafter and posterior corneal aberrations changed constantly over 12months.

Descemetorhexis Without Graft Placement for the Treatment of Fuchs Endothelial Dystrophy: Preliminary Results and Review of the Literature.

To report our preliminary experience with a central descemetorhexis without graft placement in Fuchs endothelial corneal dystrophy (FECD) and to review the existing literature on the topic. A 4-mm central descemetorhexis was performed in 5 patients (4 women, 1 man; mean age: 69.8 ± 8.6 yrs; range: 57-78 yrs) with FECD. All patients had central confluent guttae, undetectable central endothelial cell count, healthy peripheral corneal endothelium, no clinically evident bullous keratopathy, and no ocular comorbidities. In 3 patients, the procedure was combined with phacoemulsification and intraocular lens implantation. All patients completed at least 6 months of postoperative follow-up (mean follow-up 9 ± 2.5 mo; 7-13 mo). Endothelial repopulation of the central stroma was completed in all patients by the third month. Corneal clarity was achieved in 4 of 5 patients. The patient with persistent edema and haze had the highest preoperative central pachymetry. A final improvement in corrected visual acuity was achieved in 4/5 patients. A reduction in preoperative central pachymetry was observed in all cases. All patients developed deep stromal opacities around the margin of the descemetorhexis, which did not resolve over the follow-up time. Abnormal corneal topography and irregular astigmatism developed in 3 of 5 patients; these patients achieved 20/20 corrected distance visual acuity with rigid gas-permeable contact lens fitting. In partial concordance with previous studies, preliminary outcomes of a central descemetorhexis in FECD performed without endothelial graft placement seemed rather unpredictable. Baring of central stroma may trigger a variable wound-healing response with subsequent posterior stromal scarring and topographical irregularity.

Revisiting the Cornea and Trabecular Meshwork Junction With 2-Photon Excitation Fluorescence Microscopy.

To investigate the collagen and elastin architecture at the junction of the human cornea and trabecular meshwork (TM). The cornea, TM, and ciliary body (CB) tendons of unfixed human corneal buttons were imaged with an inverted 2-photon excited fluorescence microscope (FluoView FV-1000; Olympus, Central Valley, PA). The laser (Ti:sapphire) was tuned to 850 nm for 2-photon excitation. Backscatter signals of second harmonic generation and autofluorescence were collected through a 425/30-nm emission filter and a 525/45-nm emission filter, respectively. The second harmonic generation signal corresponds to collagen fibers, and the autofluorescence signal corresponds to elastin-containing tissue. Tissue structure representations were obtained through software-generated reconstructions of consecutive and overlapping (z-stack) images through a relevant sample depth. Collagen-rich CB tendons insert into the cornea between Descemet membrane (DM) and posterior stroma along with elastin fibers originating from the TM. The CB tendons directly abut DM, and their insertion narrows as they course centrally in the cornea, giving a wedge appearance to these parallel collagen fibers. Approximately 260 μm centrally from the edge of DM, the CB tendons fan out and merge with pre-DM collagen. As the CB tendons enter the cornea, they form a dense collagenous comb-like structure orthogonal to the edge of DM and supported by a delicate elastin network of interwoven fibers originating from the TM. Two-photon excited fluorescence microscopy has improved our understanding of the peripheral corneal architecture. CB tendon insertions in this region may contribute to the radial tears encountered when preparing DM endothelial keratoplasty grafts.

Rapid corneal thinning and perforated ulcerative keratitis in a patient with relapsing polychondritis

BackgroundTo report rapid corneal thinning and perforation in a case with relapsing polychondritis.Case presentationA 43 year-old male diagnosed with relapsing polychondritis suffered from bilateral scleritis, bilateral swelling of pinna, saddle nose and tracheal stenosis. The patient presented with right eye pain and redness for one month. Slit lamp examination of the right eye showed 80% peripheral corneal thinning between 3 and 7 o’clock. The best-corrected visual acuity (BCVA) was 1.0 bilaterally. The degree of corneal thinning worsened to 90% after one week of oral corticosteroid use. Subsequently, topical cyclosporine 2% eye drops four times a day, oral doxycycline 100 mg twice a day and oral vitamin C 2 g daily were added. The corneal thinning gradually improved to about 60%. However, the patient rapidly tapered oral prednisolone against medical advice and returned with an acute drop in vision in his right eye. Slit lamp examination of the right eye showed peripheral corneal perforation with iris prolapse. An emergency repair with cyanoacrylate glue was performed. Intravenous methylprednisolone 1 mg/kg body weight was administered for three days and 1 g/day intravenous immunoglobulin was administered every four weeks. At 3 months postoperatively, BCVA in the right eye was 0.6. Slit lamp examination showed a well-formed anterior chamber with glue in situ.ConclusionsRelapsing polychondritis may be associated with rapid corneal thinning. The clinicians should be aware of the possibility of corneal perforation in these cases. Cyanoacrylate glue is a viable temporary management option in such scenarios.

CLINICAL AND FUNCTIONAL OUTCOMES OF VARIOUS SURGICAL APPROACHES TO THE TREATMENT OF PROGRESSIVE KERATOKONUS

The article analyzes the results of surgical treatment of progressive early and late-stage keratoconus using a femtosecond laser. Three groups of patients (n = 80, 80 eyes) were operated on for progressive stages I-III keratoconus. Based on the Amsler-Krumeich classification, corneal collagen cross-linking with excimer-laser-assisted deepithelialization is considered to be the treatment of choice for progressive keratoconus (stages I-II) with central cornel thickness due to its efficacy and stability. Corneal collagen crosslinking with a femtosecond-assisted intrastromal pocket for administration of a photosensitizer and local ultraviolet irradiation is considered to be the treatment of choice for progressive keratoconus (stages I-II) with peripheral corneal thickness. Intralamellar keratoplasty with corneal segment implantation can effectively arrest the progression of stage III keratoconus and improve visual acuity both in the short and long term through improving anterior and posterior corneal surface regularity. All cases showed a statistically significant increase in visual acuity (NCD and IHEC), a decrease in keratometric corneal parameters, and a decrease in anterior and posterior corneal elevation.

Surgical amniotic membrane transplantation after conjunctival and limbal tumor excision.

To evaluate the clinical results of patients treated by amniotic membrane transplantation (AMT) following excision of conjunctival and limbal tumors. A total of 14 eyes of 14 patients who underwent AMT after total lesion-free tumor excision and perilesional cryotherapy were evaluated. The excised tumors comprised 7 conjunctival intraepithelial neoplasia, 5 conjunctival nevus, 1 primary acquired melanosis, and 1 squamous cell carcinoma. Limbus was involved in 10 cases, whereas cornea was involved in 6 cases. The average measurement of the tumor base was 14.8 mm (range 6-20 mm, SD 16 mm). The mean follow-up time period was 17.5 months (range 6 -60 months, SD 20 months). Complete healing occurred in eight eyes, but limbal cell deficiency developed in two eyes. Four cases had recurrence and were treated with the same surgical and medical procedures; during follow-up after recurrence, superficial peripheral vascularization and corneal scar were noted to have developed. AMT was effective for reconstruction of tissue defect after excision and cryotherapy of limbal and conjunctival tumors. In most of these cases, complete healing was achieved with a smooth, stable, and translucent surface.

Use of rituximab for granulomatosis with polyangiitis-associated peripheral ulcerative keratitis

Abstract A 31-year-old female, presented with polyarthralgia, asymmetrical polyarthritis, fever, vasculitis skin lesions, together with decreased visual acuity in the right eye with severe peripheral corneal melting, peripheral ulcerative keratitis, fibrin hypopyon and posterior synechiae. Given the clinical and paraclinical findings with positive C-ANCA (anti-neutrophil cytoplasmic antibodies), the patient was diagnosed with granulomatosis with polyangiitis with ocular (corneal melting, peripheral ulcerative keratitis and uveitis), and systemic involvement. Treatment was started with methylprednisolone and cyclophosphamide, but due to poor control, Rituximab was subsequently administered, with medical improvement.

Peripheral Ulcerative Keratitis Associated with HCV-Related Cryoglobulinemia

Purpose To describe a case of peripheral ulcerative keratitis associated with type II cryoglobulinemia in the context of Hepatitis C infection. Methods Case report and literature review. Results A 36-year-old male patient presented to our emergency department with unilateral moderate pain in his right eye, associated with redness and photophobia. Medical background elicited a history of Hepatitis C and IV illicit drug abuse. Ocular examination revealed a BCVA of 20/30 of the affected eye and slight discomfort with eye movement. Biomicroscopy revealed a ring shaped peripheral corneal ulcer, with a dense white stromal infiltrate sparing the limbus, plus an adjacent area of mild anterior diffuse nonnecrotizing scleritis. No intraocular inflammation was present. Posterior segment was normal. The patient was placed under oral prednisolone (1 mg/Kg/day) with gradual tapering. A dramatic clinical response occurred, with complete resolution of the clinical condition. Systemic analytic workup aiming at autoimmune and infectious diseases was negative, except for high HCV-viral load and the presence of type 2 cryoglobulins. Conclusion Albeit rare, cryoglobulinemia, even in the absence of systemic vasculitis, should be considered in the differential diagnosis of PUK, when systemic workout for autoimmune diseases is negative.

Peripheral Ulcerative Keratitis Associated with Autoimmune Disease: Pathogenesis and Treatment

Peripheral ulcerative keratitis (PUK) is type of crescent-shaped inflammatory damage that occurs in the limbal region of the cornea. PUK is always combined with an epithelial defect and the destruction of the peripheral corneal stroma. PUK may have a connection to systemic conditions, such as long-standing rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Wegener granulomatosis (WG), relapsing polychondritis, classic polyarteritis nodosa and its variants, microscopic polyangiitis, and Churg-Strauss syndrome. However, the most common connection is with RA, which is also the focus of this review. The pathogenesis of PUK is still unclear. It is thought that circulating immune complexes and cytokines exert an important influence on the progression of this syndrome. Treatment is applied to inhibit certain aspects of PUK pathogenesis.

Ophthalmology national normative database series (2): Gonioscopic character of the normal anterior chamber angle in sudanese adults

Background: The anterior chamber angle (ACA) is the anatomical angle bounded by the iris root and the peripheral corneal vault that comprises the aqueous outflow drains, namely the trabecular meshwork (TM) and the Schlemm's canal. The assessment of the ACA is used to classify glaucoma into open or narrow angle glaucoma's. Objective: The aim of this study is to determine the normal range values of the gonioscopic character of the ACA in adult Sudanese population and to define the effects of age, gender, and tribal ethnicity on these values. Materials and Methods: Three hundred ninety-eight eyes (n = 396); of 198 adults volunteers Sudanese healthy workers, from two factories in Khartoum, North district, were enrolled in this study; over a period of 3 months from January 1, 2009 to March 30, 2009. One hundred and sixty males 38 were females; aged ranged from 18 to 50 years. All participants underwent systematic static and dynamic gonioscopy by Posner Gonio lens in conjunction with Haag- Streit slit lamp. Then, the ACAs were graded according to Shaffer grading and classification system. The effect of age, gender and tribal ethnicity on ACA was analyzed. Then, the overall grading and TM Pigmentation analysis were done with special grading criteria specifically designed for this study (Manal–Saleem ACA Overall Grading System and Saleem-Manal TM Pigmentation Grading System). Results: In total, 198 (n = 198) Sudanese adults were recruited for the study with the mean age of the study group was 43 ± 16 years (range: 18–50 years). About 80.8% of males and 19.2% of females. 77.8% have open ACA and 19.2% narrow ACA, 0.5% closed ACA, and 2.5% with Creeping ACA. Open ACA is more in males (81.3%) than female (63.2%) while narrow ACA is more in female (34.2%) than male (15.6%). Closed and creeping ACA are similar in the two sexes. The effects of tribal ethnicity was not so profound as both the Arabs (84.1%) and Africans (87.5%) origin groups were showing minor differences in the high rate of open-angle (3.4% more in the African's) and narrow ACA (2.9% more in Arab's) apart from the Bejja groups, who recorded 100% narrow ACA while the Nubian groups of Far North recorded a lower percentage of the open ACA (78.6%) and higher of narrow ACA (17.9%). Narrow ACA was proved to be more with older age (25% as compared 10–12.5%). The TM Pigmentation in the younger age groups was found to be of lightly pigmented in 66.7% and heavily pigmented in 33.3%. A result which was affected by tribal ethnicity; 54.9% of Arab origin groups have lightly pigmented TM while 92.0% of African origin groups presented with heavily pigmented TM. In general, pigmentation was shown to be more heavily in the inferior quadrant rather than superior and horizontal quadrants. Conclusion: There is a higher rate of open ACA (77.8%) in Sudanese Adults with low rate (19.2%) of narrow ACA, followed by an even more lower rate of creeping ACA 2.5% and scarcely closed ACAs (0.5%). The average Sudanese ACA TM pigmentation is 35.4% being of light pigmentation and 64.6% of heavy pigmentation with highly significant tribal, age, and Quadrantic variations (P = 0.000).

Ocular acne rosacea in tertiary eye center in Saudi Arabia.

To report the most common presenting signs and symptoms of ocular rosacea for timely diagnosis and management. A retrospective chart review of 23 patients with a diagnosis of acne rosacea or a non-specific diagnosis was performed at a tertiary eye hospital. Patients with lid changes such as recurrent blepharitis; meibomianitis; recurrent chalazia; facial skin change such as papules, telangiectatic blood vessels, and/or rhinophyma were included. Data were collected on patient demographics, presenting symptoms, visual acuity, dermatologic findings and treatment. There were 23 patients documented with acne rosacea with dermatologic facial findings associated with lid and/or corneal findings of peripheral thinning and vascularization. Two cases had a serious spontaneous peripheral corneal perforation. Most of the patients had no clinically significant change in visual acuity. The diagnosis of ocular acne rosacea was straightforward despite non-specific findings. Diagnostic delay can result in serious complications.

High-Resolution Optical Coherence Tomography in the Differentiation of Inflammatory Versus Noninflammatory Peripheral Corneal Thinning.

To evaluate whether high-resolution optical coherence tomography (HR-OCT) can aid in differentiation of inflammatory versus noninflammatory causes of peripheral corneal thinning. Retrospective chart review of 10 patients with peripheral corneal thinning and their respective slit-lamp photographs and HR-OCT images. Ten patients were identified who had peripheral corneal thinning and HR-OCT images. Five had a clinical history consistent with Terrien marginal degeneration (TMD), whereas 5 had thinning believed to be inflammatory in origin. In the eyes with presumed TMD, patients denied pain or inflammation. HR-OCT images demonstrated stromal thinning in the presence of an intact epithelium. The stroma underneath the epithelium in the area of thinning had a similar reflectivity pattern as the nonaffected cornea. There was epithelial marsupialization evident in 2 of the 5 images. In the 4 patients with a clinical history of inflammation (bulbar hyperemia and pain), and in the 1 patient with active inflammation at the time of HR-OCT imaging, HR-OCT also demonstrated thinning with an intact epithelium. In contrast to the TMD group, in the group with signs of inflammation, a dense hyperreflective band was noted in the stroma directly below the epithelium in the area of thinning, suggestive of scarring and/or cellular infiltration. In patients with a clinical history of inflammation and corneal thinning, HR-OCT revealed a hyperreflective band directly under the epithelium in the area of thinning, which was not seen in patients with presumed noninflammatory melts and thinning.

Relationship between Corneal Thickness and Radius to Body Height.

To investigate the possible association between body stature (height) and corneal thickness and radius in younger-adult Caucasians, especially within the context of previously published literature. Body height and weight were measured in 109 healthy subjects, with an average age of 24 ± 6 years (mean ± SD). Subjects underwent an ophthalmic assessment including anterior segment imaging by Scheimpflug topography and specular microscopy. Central and peripheral corneal thickness and corneal radius were analyzed. The relationship between body stature and corneal parameters was assessed using simple and multiple regression analysis. Effect size was determined by generating regression and correlation coefficients. Body height ranged from 1.54 to 1.86 m (mean ± SD 1.67 ± 0.08 m), central corneal thickness from 465 to 629 μm (554 ± 33 μm), whereas corneal radius measured between 7.16 and 8.49 mm (7.75 ± 0.24 mm). Body height was weakly associated with central corneal thickness and peripheral corneal thickness (r ≥ -0.180), and moderately with corneal radius (r = 0.351). Based on the regression equations, central corneal thickness decreases by 8 μm, whereas corneal radius increases by 0.11 mm for each 0.1-m difference in body height. No significant correlations were found for similar assessments using body weight or body mass index. Differences in corneal radius and corneal thickness can be linked to body stature. However, effect sizes were consistently small and no more than 13% of the variability in corneal curvature could be explained by variations in body stature.

Abstracts: European Society of Veterinary Ophthalmologists, Toulouse, France, October 6‐9, 2016

Purpose: To evaluate the effects of 2% Dorzolamide, 0.5% Timolol and 0.005% Latano- prost on the biometrics of the anterior segment in normotensive cats. Material/Methods: Three groups of 15 clinically healthy randomly selected cats received one single molecule on the right eye during 7 days (Group 1: 2% Dorzolamide BID, Group 2: 0.5% Timolol BID, Group 3: 0.005% Latanoprost SID). Left eyes received no treatment and were used as con- trols. Complete ophthalmic examination, IOP measurement and anterior segment assessment by Ultrasound Biomicroscopy (UBM) were performed in the same conditions at day 1 and day 7, on both eyes. Eight anatomical parameters of the anterior segment were evaluated: the geometric iridocorneal angle (ICA) – formed by the plane of the iris root and the inter- nal corneoscleral limbus – the width of the opening of the ciliary cleft (CC), the width of the mid-CC, the length of the CC, the anterior chamber (AC) depth (distance between the corneal endothelium and the anterior lens capsule), the central and peripheral corneal thick- nesses, then the distance between the anterior lens capsule and the internal corneoscleral limbus. Results: The use of the controlateral eye as control was statistically validated, as well as the representativeness of fifteen-cat cohorts. A significant decrease of IOP was observed only for dorzolamide (5.3%). None of the eight anatomical parameters were statistically modified by the topical instillation of the three drugs. Discussion: The use of the three first-line antiglaucomatous agents does not significantly alter the anterior segment architecture in normotensive cats.

Upregulation of NLRP3 inflammasome components in Mooren's ulcer.

Mooren's ulcer (MU) is a peripheral corneal ulceration of presumed autoimmune etiology. NLRP3 inflammasome has been shown to be involved in a variety of autoimmune and auto-inflammatory diseases. However, the role of NLRP3 inflammasome in MU has not been investigated. Here, we evaluate the expression of NLRP3 inflammasome and its downstream inflammatory factors in human MU. Conjunctival biopsy specimens were obtained from seven patients with MU and six healthy donors. The removed conjunctivas were histopathologically evaluated for NLRP3 inflammasome component expression using antibodies directed against NLRP3, Caspase-1 (CASP1), and Interleukin-1β (IL-1β). Quantitative real-time PCR was used to measure the mRNA expression of NLRP3 and IL-1β, and the protein expressions of NLRP3, pro-CASP1, CASP1, and IL-1β were detected by Western blotting. NLRP3 and IL-1β mRNA expression showed higher levels in the MU group than in healthy controls. Western-blot and immunofluorescence analysis also showed that basal expression of NLRP3 inflammasome components (NLRP3, CAPS1, and IL-1β) was elevated in patients with MU compared with healthy controls. Most importantly, we found that the cleavaged form of CASP1 and IL-1β was significantly increased in MU patients compared with healthy donors, which indicates that the upregulation of NLRP3 inflammasome was probably responsible for the enhanced IL-1β production in MU patients. This study demonstrated that the expression of the NLRP3-CASP1-IL-1β signaling pathway was markedly increased in the conjunctival lesions of patients with MU, suggesting the involvement of NLRP3 inflammasome in the onset and development of the inflammation in MU.

Case‐finding for angle closure: the diagnostic value of simple tests for estimating limbal and central anterior chamber depth

PurposeTo evaluate the diagnostic accuracy of limbal and central anterior chamber depth measurement for detecting gonioscopically narrow anterior chamber angles (ACAs).MethodsA total of 78 subjects with narrow or open ACAs underwent an assessment of anterior chamber depth at the temporal limbus by estimating depth as a percentage of peripheral corneal thickness (van Herick test) by one examiner and just‐touching‐slit‐length measurements of the central anterior chamber depth (Smith's test) by a second examiner. Diagnostic performance was compared with (a) a gonioscopy reference standard, performed by a third examiner using the International Society of Geographical and Epidemiological Ophthalmology (ISGEO) definition of primary angle closure and (b) a classification based on clinical opinion of occludability. All examiners were masked regarding each subject's clinical status and other test results. Sensitivity, specificity, and partial area under the receiver operating characteristic curve (AUROC) were generated.ResultsThe van Herick grading cutoff of 25% or less and ISGEO gonioscopic classification achieved 80% (95% CI 65–89) sensitivity and 92% specificity (95% CI 80–97) for narrow angle detection, with specificity reaching 97% (95% CI 87–100) for a cutoff of less than or equal to 15%. Notably, with a gonioscopic classification based on clinical opinion of occludability, van Herick (≤25%) together with Smith's test (≤2.50 mm) detected 100% of narrow angle subjects.ConclusionsThe van Herick test provides good discrimination between narrow and open angles both alone, and in combination with the measurement of central anterior chamber depth. These tests show good potential for identifying individuals who may benefit from further gonioscopic assessment in a case‐finding or screening setting.

OCT spectralis for terrien marginal degeneration diagnosis

PurposeTerrien marginal degeneration is a rare idiopathic form of corneal degeneration that affects peripheral cornea, it occurs at any age and 75% of patients are males. This condition is most commonly bilateral and asymmetric.Patients are often asymptomatic but they may also complain of irritation of the eye and progressive loss of visual acuity due to oblique astigmatism. Rarely the disease may lead to corneal perforation but may also occur spontaneously or secondary to trauma.The most important corneal modifications in Terrien marginal degeneration, frequently located superonasaly, are observed in the stroma showing yellow – white opacities composed of lipids with associated vascularization.Spectral Domain OCT because of its capacities to describe corneal anatomy might be useful in the diagnosis of the Terrien marginal degeneration.MethodsWe present a case of a 75 year old male who was examined and followed during several months in the department of ophthalmology, Lozano Blesa University Clinic Hospital, Zaragoza, Spain, with slit lamp, corneal topographic maps and spectral domain‐ OCT.ResultsSD‐OCT confirmed the peripheral corneal thinning seen with corneal topographic map and slit lamp. It showed intact epithelial and endothelial layers surrounding the stromal cavity formation, and a perforation of the endothelium underneath this cavity.ConclusionsWe point out the utility of spectral domain optical coherence tomography in the diagnosis and follow‐up of cavity formation in the peripheral cornea in Terrien marginal degeneration.

Terrien marginal degeneration presenting with corneal perforation

PurposeTerrien marginal degeneration is a slow‐progressing, bilateral but asymmetric degeneration of the peripheral cornea. The spontaneous corneal perforation is rare. To report a imminent corneal perforation as a presenting sign Terrien marginal degeneration, treated with amniotic membrane implant.MethodsA 70‐year‐old man presented with complaints of pain, redness,and decreased visión in the left eye (LE). Examination revealed peripheral corneal thinning 360º with superficial vascularization and secondary lipid keratopathy. There was an area of more thinning at the 5 o′clok position. His best‐corrected visual acuities (BCVAs) were 90°−4 + 4: 0.8 on the RE and 80°−3.75 + 4: 0.6 on the LE. Corneal topography with Orbscan of the LE revealed high oblique astigmatism with Sim K values of 48.75D at 140° and 43.25D at 50°. AS‐OCT showed corneal thinning and cavity formation with intact epithelial layer and affected endothelium in the thinned área.ResultsDue to the imminet corneal perforation was selected to make an amniotic membrane implant. Several circular layers of amniotic membrane rolled up on themselves and placed in the thinned área, fixing them with nylon 10‐0 suturing it to perilesional healthy cornea. The post‐operative AS‐ OCT reveals good adhesion of the amniotic membrane and corneal thickness recovery.ConclusionsTerrien marginal degeneration is an unusual cause for a spontaneous corneal perforation. Patients with this disorder should be warned about this possibility. Surgery (lamellar graft, amniotic membrabe implant) can preserve corneal integrity and is indicated when conventional options fail to maintain vision or if perforation is imminent.