VOLUME 83 - ISSUE 2

Purpose: The present study’s aim was to compare the biomechanical properties of corneal tissue in patients who underwent deep anterior lamellar keratoplasty (DALK) surgery, with successful big bubble formation and manual lamellar dissection, during failed big bubble formation.
Methods: This retrospective comparative study included 60 eyes from 60 keratoconus patients who previously underwent DALK surgery. These patients were categorized as big bubble (+) or big bubble (-) based on the success or failure of big bubble formation during the surgery. The big bubble (+) group included 42 eyes, while the big bubble (-) group had 18 eyes. Moreover, the patients were regrouped as 0.25 mm and 0.50 mm to evaluate the effects of the disparity between donor and trephine punches on the biomechanical properties of the cornea. These biomechanical properties, characterized by corneal hysteresis and the corneal resistance factor, were measured using the Ocular Response Analyzer 12 months after the surgery.
Results: There was no statistically significant difference between the big bubble (+) and big bubble (-) groups in the biomechanical properties of the cornea (corneal hysteresis: 10.06, 10.25; p=0.716/corneal resistance factor: 10.15, 10.07; p=0.805, respectively). In addition, pachymetry results were not statistically different between the two groups. Multivariate regression analysis revealed that corneal hysteresis and corneal resistance factor were positively associated with central corneal thickness (p<0.001/r²=0.506; p<0.001/r²=0.561, respectively). However, the study did not demonstrate a relationship between any of the punch sizes and corneal hysteresis or between the punch sizes (p=0.673) and the corneal resistance factor (p=0.643).
Conclusions: The corneal hysteresis and corneal resistance factor values were similar in big bubble and manual lamellar dissection after DALK. Thus, manual lamellar dissection was not a disadvantage considering the cornea’s biomechanical properties.

Keywords: Cornea/physiopathology; Corneal transplantation/methods

Purpose: To analyze subclinical keratoconus topography indexes using Pentacam and Orbscan-II measurements to identify evidences for seeking sensitive indexes to screen and diagnose subclinical keratoconus.
Methods: Fifty healthy participants (50 eyes) and 40 patients with subclinical keratoconus (40 eyes) were included. Seven common parameters including corneal thickness at the thinnest point; minimum curvature of the front surface (minimum simulated keratometry value, SimK’s Min); maximum curvature of the front surface (maximum simulated keratometry value, SimK’s Max); the frontal corneal surface best-fit spherical radius of the curvature; the back corneal surface best-fit spherical radius of curvature; the anterior corneal surface height (anterior Diff value); and the posterior corneal surface height (posterior Diff value) measured by Pentacam and Orbscan-II between normal and subclinical keratoconus eyes were compared.
Results: Statistical differences between the healthy and subclinical keratoconus groups (p<0.01) were found in all corneal parameters measured using both devices. Differences in the minimum curvature of the front surface (SimK’s Min), thinnest point, anterior Diff value, and posterior Diff value were significant between Pentacam and Orbscan-II in the subclinical keratoconus group (p<0.05).
Conclusion: The findings of this study identify the differences between normal and subclinical keratoconus eyes at the minimum curvature of the front surface, maximum curvature of the front surface, frontal corneal surface best-fit spherical radius of curvature, back corneal surface best-fit spherical radius of curvature, Anterior Diff value, and Posterior Diff value measures using Orbscan II and Pentacam that can help eye care practitioners clinically diagnose subclinical keratoconus.

Keywords: Keratoconus/diagnosis; Corneal topography; Cornea/diagnostic imaging; Diagnostic imaging/methods; Comparative study

Purpose: To evaluate causes and management of congenital corneal opacities (CCO) diagnosed in a tertiary care eye center and to compare the data with a previous study at the same institution.
Methods: Computerized medical records in all patients with congenital corneal opacities diagnosed in the Cornea Service at Wills Eye Hospital (Philadelphia, PA) between January 1, 2007, and December 31, 2015, were retrospectively reviewed. Children aged 12 years and younger at the first visit were included in the study. Patients’ demographics, ocular diagnosis, laterality, associated ocular abnormalities, other ocular surgery performed prior or subsequent to the first visit, and their treatment were extracted from the medical records.
Results: A total of 77 eyes in 56 patients were examined. The mean age at presentation was 32.8 ± 44.2 months, with the mean follow-up period of 26.7 ± 30.1 months. The most frequent diagnosis was Peters anomaly (53.2%), followed by limbal dermoid (13.0%), aniridia with glaucoma and microphthalmos (6.5%), sclerocornea and congenital glaucoma (5.2%), idiopathic (3.9%), Axenfeld-Rieger anomaly and Hurler syndrome (2.6%), and microcornea (1.3%). Primary keratoplasty was performed in 26 eyes, with the outcome rate in the clear cornea of 76.0% during the follow-up.
Conclusion: Peters anomaly is the most common cause of congenital corneal opacities encountered at our institution. Penetrating keratoplasty is the most frequent choice of corneal surgery to treat congenital corneal opacities. Additional interventions during penetrating keratoplasty were moderately positively correlated with graft failure. This study also shows the rates of some etiologies of that changed over the recent decades in our tertiary care Cornea Service. Although Peters anomaly remains the most common presenting reason for congenital corneal opacities, its rate appears to be increasing over the recent decade. Congenital corneal opacities due to birth trauma, which is one of the preventable causes, were observed in a previous study in our clinic; however, no new cases were noted in this study.

Keywords: Cornea/abnormalites; Corneal opacity/congenital; Keratoplasty, penetrating; Peters anomaly; Tertiary healthcare

Purpose: To analyze whether inter-eye osmo larity differences were related to dry eye symptomatology.
Methods: A total of 135 participants were randomly recruited from those who visited in the Optometry Clinic of the Optometry Faculty (Universidade de Santiago de Compostela). In a single scheduled session after the recruitment, Ocular Surface Disease Index was filled out following the standard instructions and TearLab measurements were made in both the participants’ eyes (10-15 min lapse). Osmolarity values were compared between the right and left eyes and the absolute inter-ocular difference (|OD-OS|) correlated with the Ocular Surface Disease Index score for the whole sample. Based on the Ocular Surface Disease Index score, the sample was divided into four symptomatic subgroups, and differences in the |OD-OS| values were calculated.
Results: The whole sample showed a statistically significant inter-eye osmolarity difference (p=0.025; |OD-OS| = 9.2 ± 9.3 mOsm/l) and the correlation between Ocular Surface Disease Index and |OD-OS| (r=0.369; p<0.001). A statistically significant difference was found in the |OD-OS| value between symptomatic subgroups (Kruskal-Wallis, p=0.003). Mann-Whitney U test showed a significant difference between asymptomatic vs. moderate (p=0.006) vs. severe symp tomatic patients (p=0.001) and between mild vs. severe symptomatic patients (p=0.045), whereas no difference on |OD-OS| was found between participants with contiguous symptomatic subgroups (all p≥0.174).
Conclusion: Tear film inter-eye osmolarity differences are significantly higher in severe dry eye disease symptoms.

Keywords: Osmolar concentration; Dry eye syndromes; Lacrimal apparatus/chemistry; Tears/chemistry

Purpose: To compare the impact of ocular changes between systemic treatment with doxycycline and low-dose oral isotretinoin in patients with moderate-to-severe papulopustular rosacea.
Methods: Patients were randomized to receive either isotretinoin 0.3-0.4 mg/kg (group A) or doxycycline 100 mg/ day (group B) for 16 weeks. Ocular symptoms were searched and evaluated, including best-corrected visual acuity (BCVA), Schirmer test, breakup time, rose bengal staining score, and meibomian gland dysfunction grading. The patients were retested at the end of treatment.
Results: The present study included 39 patients (30 females and 9 males). Best-corrected visual acuity was > 20/30 in >90% of patients in both groups and did not change after treatment. After treatment, improvement in ocular symptoms and meibomian gland dysfunction was more pronounced in group B (p<0.05); the other parameters did not reach statistical significance.
Conclusion: Doxycycline improved meibomian gland dysfunction, ocular symptoms, and ocular surface in patients with rosacea. Even though some patients experienced worsening meibomian gland dysfunction and symptoms, no subject experienced any serious complications after administration of low-dose isotretinoin.

Keywords: Rosacea/drug therapy; Doxycycline/therapeutic use; Doxycycline/administration & dosage; Isotretinoin/therapeutic use; Isotretinoin/administration & dosage; Ocular surface; Blepharitis

Purpose: To evaluate the characteristics of ocular injuries among elderly patients admitted to an urban level I trauma center because of major trauma from 2008 to 2015.
Methods: A retrospective chart review was conducted of patients aged >65 years admitted with ocular injuries that were identified with ICD-9 codes. Tabulated data were analyzed using the Student’s paired t-test, the chi-squared test, and regression analysis using STATA/MP-12 software. Significance was set at p<0.05.
Results: Of a total of 861 patients, 221 (25.7%) admitted for major trauma and ocular injuries were elderly. The mean age of these patients was 80.3 years (median =79.2 years; interquartile range=63.8-94.6 years). Of these patients, 40.7% were males and 59.3% were females. The males were younger than the females (mean age, 77.3 vs. 82.4 years, respectively, p<0.001). Race was documented as white (30.8%), black (13.6%), and “other” (54.3%), with 67.5% of the “other” group (36.7% overall) identified as Hispanic. The most frequent injuries were contusion of the eye/adnexa (68.2%), orbital wall fractures (22.2%), and an open wound of the ocular adnexa (18.1%). Males had a 2.64-fold greater risk of orbital wall fractures (95% confidence interval [CI]=1.38-5.05, p<0.003). Patients with orbital wall fractures had higher injury severity scores than those without (95% CI=14.1-20.9 vs. 6.8-8.6, respectively, p<0.001). The most common injuries were falls (77.8%) and pedestrian/motor vehicle accidents (6.8%). Falls occurred mostly at home (51.7%), on the street (13.9%), and in hospitals/nursing homes (12.2%). Those falling at home were older than those falling at other locations (95% CI=81.8-85.4 vs. 77.0-80.6 years, respectively, p<0.002).
Conclusions: Ocular injuries in elderly Bronx patients most commonly occurred in females due to falls in the home/nursing home setting. Public health measures addressing identifiable individual and environmental risks in these common locations would be most beneficial in reducing the incidence of ocular injuries in this population.

Keywords: Eye injuries; Epidemiology; Age; Accidental falls; Urban population

Purpose: To investigate retinal microvasculature changes in patients treated with anti-VEGF for macular edema secondary to branch retinal vein occlusion.
Methods: We examined 38 eyes of 19 patients for the study. We measured superficial and deep capillary plexus vessel densities (%), foveal avascular zone areas (mm²), and central macular thicknesses.
Results: Parafoveal superficial and deep capillary plexus values were significantly lower in eyes with branch retinal vein occlusion than in fellow eyes (p<0.001). We found a significant increase in parafoveal deep capillary plexus values after the anti-VEGF treatment (p=0.032). The mean foveal avascular zone was larger in eyes with branch retinal vein occlusion than in control eyes (p<0.001). The mean central macular thickness was significantly higher in eyes with branch retinal vein occlusion than in controls, and we observed a significant decrease in central macular thickness after anti-VEGF treatment (<0.001). In addition, the cystic structures in the deep capillary plexus regressed.
Conclusion: Optical coherence tomography angiography enables qualitative and quantitative evaluations during follow-up of patients treated for branch retinal vein occlusion.

Keywords: Retinal vein occlusion; Tomography, optical coherence; Endothelial growth factors/antagonists & inhibitors

Purpose: Inferior eyelid laxity is classically evaluated using “snap-back” and “distraction” tests. This study aimed to assess the reproducibility of the technique used to indirectly quantify the horizontal tension in the lower eyelids using digital image processing.
Methods: This longitudinal study was conducted to assess the reproducibility of a new technique that quantifies the horizontal tension in the lower eyelid. The study was conducted at the Hospital das Clínicas of Porto Alegre. The protocol was established by two trained ophthalmologist examiners, allowing intra- and interobserver agreement analyses. Image acquisition was done in two stages: the first image was captured with the eyelid in primary gaze position and the second with the eyelid in traction position. All images and measurements were processed using Image J 1.33µ software from the National Institute of Health. The Bland-Altman method, intraclass correlation coefficients, concordance correlation coefficients, and technical measurement error were used to evaluate reproducibility.
Results: The study participants comprised healthy individuals with no ophthalmologic pathologies. The measurements obtained in the neutral position showed a slightly higher agreement than those obtained in the traction position. The mean difference between the measurements performed in the traction position was 0.028 ± 0.7 mm and 0.014 ± 0.9 mm in the intra- and interobserver analyses, respectively. The Bland-Altman method demonstrated adequate confidence limits for both measurements. Correlation coefficients for measurements varied between 0.87 [95% confidence interval (CI) 0.68-0.95] and 0.91 (95% CI 0.77-0.97) in the neutral position and between 0.72 (95% CI 0.37-0.89) and 0.76 (95% CI 0.4-0.91) in the traction position.
Conclusion: A high intra- and interobserver concordance was observed in the studied method to quantify lower eyelid tension. The proposed method is simple and easily reproducible, and to the best our knowledge, this is the first method that quantifies lower eyelid horizontal tension on the basis of digital image processing. This modified distraction test might be useful in studies quantifying lower eyelid horizontal tension.

Keywords: Eyelids; Eyelid diseases; Ectropion; Entropion; Digital image

Purpose: To investigate the relationships between (i) thickness of the retinal nerve fiber layer, optic nerve head topography, and visual field parameters and (ii) corneal biomechanical properties in normal controls and patients with ocular hypertension and primary open-angle glaucoma.
Methods: This observational, cross-sectional study included 68 eyes with primary open-angle glaucoma, 99 eyes with ocular hypertension and 133 control eyes. Corneal biomechanical properties, optic nerve head topographic features, retinal nerve fiber layer thickness, and visual fields were assessed in all cases. Corneal biomechanical properties, retinal nerve fiber layer thicknesses, and optic nerve head topographic features were compared among the groups. The associations between structural and functional measures of glaucomatous damage and corneal biomechanical factors were also evaluated.
Results: Significantly lower corneal hysteresis and corneal resistance factor values were observed in the primary open-angle glaucoma and ocular hypertension groups as compared with the control group, but there were no significant differences between the primary open-angle glaucoma and ocular hypertension groups. In the ocular hypertension group, no associations were observed between the corneal hysteresis and corneal resistance factor with values and the structural and functional parameters. In the primary open-angle glaucoma group, positive correlations were observed between the corneal hysteresis values and the global retinal nerve fiber layer thickness (p<0.01, r=0.27), mean retinal nerve fiber layer thickness (p<0.01, r=0.33), and mean deviation (p<0.01, r=0.26), and negative correlations were observed between the corneal resistance factor values, and the cup area (p<0.01, r=-0.39), cup-to-disk ratio (p=0.02, r=-0.28), linear cup-to-disk ratio (p=0.02, r=-0.28), and cup shape (p=0.03, r=-0.26). In the control group, weak correlations were detected between the corneal hysteresis and the cup area (p=0.03, r=0.19), cup-to-disk ratio (p=0.01, r=0.21), and linear cup-to-disk ratio (p=0.01, r=0.22).
Conclusions: Distinct correlations were identified between the corneal hysteresis and corneal resistance factor values and the functional and structural parameters in the primary open-angle glaucoma and control groups. Corneal hysteresis and corneal resistance factor may have different roles in the pathophysiology of glaucoma.

Keywords: Corneal pachymetry; Optic disk; Glaucoma; Tonometry, ocular; Nerve fibers; Retina; Visual field

Purpose: To compare the postoperative refractive predictability of IOLMaster 500 and Pentacam HR on the basis of keratometry and anterior chamber depth values in eyes with an indication for multifocal intraocular lens (IOL) implantation.
Methods: This was a retrospective study conducted on 118 eyes treated with phacoemulsification and multifocal intraocular lens implantation. Only the eyes that achieved emmetropia in the dynamic refraction performed on postoperative day 30 were included. Haigis’ formula was used in each case to calculate the intraocular lens power, and the intraocular lens with the target refraction closest to emmetropia was implanted. Four lens calculation scenarios were tested by combining keratometry and anterior chamber depth measurements obtained using the two devices.
Results: IOLMaster 500 and Pentacam HR differed with regard to mean keratometry (D 0.07 ± 0.03 D; p=0.0065) and anterior chamber depth (D 0.08 ± 0.01 mm; p<0.001). In the analysis of covariance, the following differences were obtained using the Haigis’ formula when confronted with the biometric values obtained by inserting keratometry and anterior chamber depth values, respectively: Penta/IOL x IOL/Penta (0.13 ± 0.03; p<0.0001); Penta/Penta × IOL/Penta (0.13 ± 0.03; p<0.0001); Penta/IOL × IOL/IOL (0.11 ± 0.03; p=0.001); Penta/Penta × IOL/IOL (0.11 ± 0.03; p=0.002); IOL/IOL × IOL/Penta (0.02 ± 0.03; p=0.865); and Penta/IOL × Penta/Penta (0.002 ± 0.03; p=0.99). The difference was smaller when measuring the anterior chamber depth using the IOLMaster 500, regardless of which device was used to measure keratometry.
Conclusions: Pentacam HR significantly differed from IOLMaster 500 when calculating keratometry. As regards the anterior chamber depth, the two devices were equally accurate.

Keywords: Biometry; Cataract; Interferometry; Lenses, intraocular; Multifocal intraocular lenses

Lisch corneal dystrophy is a rare corneal disease characterized by the distinctive feature of highly vacuolated cells. Although this feature is important, the nature of these vacuoles within corneal cells remains unknown. Here, we sought to analyze corneal cells from a patient diagnosed with Lisch dystrophy to characterize the vacuoles within these cells. Analyses using histopathology examination, confocal microscopy, and transmission electron microscopy were all consistent with previous descriptions of Lisch cells. Importantly, the vacuoles within these cells appeared to be autophagosomes and autolysosomes, and could be stained with an anti-microtubule-associated protein 1A/1B-light chain 3 (LC3) antibody. Taken together, these findings indicate that the vacuoles we observed within superficial corneal cells of a patient with Lisch corneal dystrophy constituted autophagosomes and autolysosomes; this finding has not been previously reported and suggests a need for further analyses to define the role of autophagy in this ocular disease.

Keywords: Autophagy; Corneal dystrophies, hereditary; Corneal opacity; Vacuoles/pathology; Humans

Gyrate atrophy is a rare metabolic autosomal recessive disorder caused by ornithine aminotransferase enzyme deficiency that leads to characteristic progressive, degenerative chorioretinal findings. Patients complain mostly of low vision, night blindness, and peripheral vision loss. Posterior subcapsular cataract, myopia, choroid neovascularization, and intraretinal cysts may be accompanying factors related to vision loss. We encountered a patient with vision loss secondary to posterior subcapsular cataract and intraretinal cysts. After treatment with topical brinzolamide and nepafenac (and without any diet modification and/or supplementation), we observed 143- and 117-µm macular thickness resolutions with 2 and 1 Snellen lines of visual gain in his right and left eyes, respectively. Also, we detected a novel homozygous mutation in the ornithine aminotransferase gene: c.1253T>C (p.Leu418Pro). Carbonic anhydrase inhibitors and/or non-steroid anti-inflammatory drugs can control macular edema in patients with gyrate atrophy-associated intraretinal cysts. The genetic variants may also be a determinant in the responsiveness to the therapy type.

Keywords: Brinzolamide; Macular edema; Genes; Mutation; Nepafenac; Ornithine; Transaminases

A 45-year-old man presented with a 3-month history of a mass located in the caruncle of his right eye. An incisional biopsy had been performed one month prior by another specialist, and the histopathology report showed basal cell carcinoma. The mass was completely excised with a 2 mm safety margin, and the large conjunctival defect was reconstructed with one sheet of amniotic membrane allograft. A histological diagnosis of pilomatrix carcinoma was established. To prevent recurrence after surgery, we added bevacizumab (25 mg/mL, 1.25 mg/mL per drop) eye drops four times per day for three months. At the one-year follow-up, the patient showed no evidence of local recurrence or distant metastasis after initial excision and remains under close follow-up. Pilomatrix carcinoma should be considered in the differential diagnosis of a caruncular mass.

Keywords: Hair follicle; Hair diseases; Skin neoplasms; Pilomatrixoma; Carcinoma, basal cell; Lacrimal apparatus diseases; Bevacizumab/administration & dosage; Diagnosis, Differential; Humans

A 37-year-old woman complained of headaches following bilateral visual loss in the past two years. She was obese and had undergone bariatric surgery three months earlier, followed by a considerable weight loss. Neuro-ophthalmic exa mination revealed a bilateral swollen optic disk. After a computerized analysis of the visual fields and magnetic resonance imaging of the brain and orbits, a diagnosis of idiopathic intracranial hypertension was made. At six months after the bariatric surgery, the patient reported no further headaches and exhibited better findings on computerized analysis of visual fields. However, fundus examination revealed persistent mild papilledema in both eyes. Ocular B-scan ultrasonography showed bilateral optic disk drusen. This report highlights the coexistence of true papilledema and pseudopapilledema due to optic disk drusen, following remission of idiopathic intracranial hypertension after a bariatric surgery.

Keywords: Papilledema; Optic disk drusen; Intracranial hypertension; Magnetic resonance imaging; Bariatric surgery; Humans; Case reportsPapiledema; Drusas do disco óptico; Hipertensão intracraniana; Imagem por ressonância magnética; Cirurgia ba riátrica; Humanos; R

Degenerative retinal diseases such as retinitis pigmentosa, Stargardt’s macular dystrophy, and age-related macular degeneration are characterized by irreversible loss of vision due to direct or indirect photoreceptor damage. No effective treatments exist, but stem cell studies have shown promising results. Our aim with this review was to describe the types of stem cells that are under study, their effects, and the main clinical trials involving them.

Keywords: Stem cells; Retinal progenitor cells; Embryonic stem cells; Induced pluripotent stem cells; Bone marrow-derived stem cells