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This review is intended to describe the therapeutic approaches for corneal blindness, detailing the steps and elements involved in corneal wound healing. It also presents the limitations of the actual surgical and pharmacological strategies used to restore and maintain corneal transparency in terms of long-term survival and geographic coverage. In addition, we critically review the perspectives of anabolic agents, including vitamin A, hormones, growth factors, and novel promitotic and anti-inflammatory modulators, to assist corneal wound healing. We discuss the studies involving nanotechnology, gene therapy, and tissue reengineering as potential future strategies to work solely or in combination with corneal surgery to prevent or revert corneal blindness.

The degree to which viral infection and the host’s immune reaction to viral particles participate in the inflammatory process across various forms of herpetic keratitis has remained controversial. This fact has created conflicts regarding the classification of and therapeutic planning for such morbidities. This review aims to stimulate reflection on the classifications’ adequacy, nomenclatures, and therapeutic approaches related to these entities. RESUMO O grau de participação da infecção viral e da reação imunológica do hospedeiro às partículas virais no processo infamatório das diferentes formas de ceratites herpéticas ainda é objeto de controvérsia. Esse fato gera conflitos de classificação e planejamento terapêutico relativos a essas morbidades. Esta revisão visa estimular a reflexão sobre a adequabilidade das classificações, nomenclaturas e abordagens terapêuticas dessas entidades.

There is limited information on functional low vision (FLV) in Latin America, especially in individuals under 50 years of age. In the present study, we retrospectively evaluated the medical records of 1393 consecutive subjects seen at a Brazilian tertiary rehabilitation service, from February 2009 to June 2016. We collected sociodemographic, clinical data, and information on optical aids and spectacle prescription. Subjects were divided into three age groups: 0 to 14 years old (children), 15 to 49 years old (young adults), and 50 years or older (older adults). The main etiologies leading to FLV in children were cerebral visual impairment (27.9%), ocular toxoplasmosis (8.2%), and retinopathy of prematurity (7.8%). In young adults, retinitis pigmentosa (7.4%) and cone/rod dystrophy (6.5%) were the most frequent, while in older adults, age-related macular degeneration (25.3%) and diabetic retinopathy (18.0%) were the leading causes. Our results indicate that preventable diseases are important causes of FLV in children in the area, and proper prenatal care could reduce their burden. The increasing life expectancy in Latin America and the diabetes epidemic are likely to increase the demand for affordable, people-centered rehabilitation centers, and their integration into health services should be planned accordingly.

PURPOSE Iris mammillations (IM) were previously described in patients with keratoconus, but the clinical implications of this finding have never been studied. Our aim was to investigate demographic, tomographic, and clinical characteristics potentially associated with the presence of IM among patients with keratoconus. METHODS This was a cross-sectional study performed among patients with keratoconus in a public-affiliated university hospital. All patients under follow-up were considered eligible to participate in the study. Participants were evaluated by 2 trained ophthalmologists and submitted to corneal tomography (Pentacam). Selected demographic, clinical, and tomographic characteristics were assessed and compared among participants with IM (IM group) and without IM (No-IM group) using the Wilcoxon test or 2-tailed Fisher exact test, as appropriate. RESULTS The study population consisted of 106 subjects and 19 (17.9%) presented with IM. The median age and interquartile range were 18 years old (14-24) in the IM group and 20 years old (17-24) in the No-IM group (P = 0.135). The female proportion was 47.3% in the IM group and 52.8% in the No-IM group (P = 0.801). Median (interquartile ranges) pachymetric values of the right eyes were 498 (466-525) for the IM group and 459 (421-482) for the No-IM group (P = 0.005). For the left eyes, the values were 490 (456-523) in the IM group and 450 (418-485) in the No-IM group (P = 0.024). CONCLUSIONS Subjects with keratoconus presenting with IM have thicker corneas than those without IM. Follow-up studies should be performed to evaluate the clinical implications of this finding.

Purpose: To describe the presence of iris mammillations (IM) in keratoconus. Design: Retrospective case series and literature review. Observations: This is a retrospective case series of eight patients presenting with keratoconus and IM, who were examined between January 2016 and December 2017 in the ophthalmology outpatient clinic. They had a median age of 14 (11–30), and all had bilateral keratoconus and diffusely distributed IM. The IM had similar presentations and similar iris colors. None had relevant medical or family diseases associated with IM. Three eyes previously had penetrating keratoplasty. Four (31%) out of 13 eyes had mean keratometry (Km) > 55D, and 4 (31%) had the thinnest pachymetry between 300 and 400μm. Conclusions and importance: To the best of our knowledge, this is the first time that IM was observed in association with keratoconus patients. The possibility that IM is an early finding in otherwise healthy patients may help to predict the future diagnosis of keratoconus. Future studies are needed to show the frequency and possible association between IM and a keratoconus prognosis. This may also demonstrate that there is a subgroup of patients with a distinct etiology of keratoconus. Keywords: Keratoconus, Cornea, Iris

Congenital cranial dysinnervation disorders are a group of complex strabismus syndromes that present as congenital and non-progressive ophthalmoplegia. The genetic defects are associated with aberrant axonal targeting onto the motoneurons, development of motoneurons, and axonal targeting onto the extraocular muscles. We describe here the surgical management of a 16-year-old boy who presented with complex strabismus secondary to hypoplasia of the third cranial nerve and aberrant innervation of the upper ipsilateral eyelid.

Purpose To report a peculiar case of adult-onset buphthalmos. Methods Review of the medical record of a 24-year-old patient with Down syndrome who developed buphthalmos in the left eye after corneal transplantation for keratoconus. Results In the next 2 years after surgery, the operated eye evolved with chronic anterior uveitis that led to progressive peripheral synechiae, oscillating intraocular pressure, cataract, graft failure, and buphthalmos. Conclusions The finding of buphthalmos of adult-onset in Down syndrome raises important issues concerning the classification of this eye condition and the responsibility for detecting and monitoring eyes with glaucoma in individuals with chromosome 21 trisomy.

Purpose: To study visual acuity, refractive errors, eccentric fixation, and reading performance in patients with toxoplasmic macular retinochoroiditis. Methods: Twenty-three participants with bilateral toxoplasmic macular retinochoroiditis and 4 with toxoplasmic macular retinocho­roiditis in their unique eye were evaluated. Participants reported their eye dominance, confirmed by the Portus and Miles test. Best corrected visual acuity, spherical equivalent refraction, magnification need, and reading speed were measured. Microperimetry (MAIA, Centervue - Padova, Italy) recorded the preferred retinal locus and fixation stability by means of the bivariate contour ellipse area. Fourteen eyes from 14 normally sighted subjects served as controls. Results: Mean ± SD best corrected visual acuity was better in the dominant eye than in the nondominant eye: 0.9 ± 0.2 (logMAR 0.5 to 1.4) vs. 1.2 ± 0.3 (logMAR 0.6 to 1.7) (p

Purpose A group of keratoconus subjects (KG) and a control group (CG) were evaluated for sensory and motor status. We tried to clarify the factors (best-corrected visual acuity [BCVA]), heterophorias, fusional amplitude, anisometropia, astigmatism) that may be associated with a binocular disturbance. Methods BCVA (logMAR) was measured. Binocular vision was checked using cover tests, striate Maddox, and a 6Δ base-down prism (simultaneous perception), a prism bar (fusion and fusional convergence break point), and Titmus Fly Test (stereopsis). Results Fifty-four subjects of the KG, 27 men (median 16 years), and 29 of the CG, 15 men (median 20 years), were evaluated. In the KG, 8 (15%) subjects had strabismus. Those whose BCVA in the worse eye was logMAR ≥0.7 had a significantly higher frequency of strabismus and absence of simultaneous perception. Spherical equivalent anisometropia ≥ 1.0 diopter (D) was significantly different in both groups as was the frequency of gross stereopsis. In comparing fine and gross stereopsis in both the KG and the CG, there was a significant difference in the frontal astigmatism between eyes in the KG (P = 0.03) and CG (P = 0.01). Conclusions In our study, the KG presented a higher frequency of strabismus and impaired binocular vision. Frontal astigmatism was different between groups with gross and fine stereopsis, in both the CG and KG. Future studies are needed to elucidate or reinforce the factors associated with the loss of binocularity in keratoconus. Testing for stereopsis may be helpful to consider in the treatment guidelines for keratoconus.

OBJETIVOS: Determinar as variações no ângulo de posicionamento ocular pós-operatório em pacientes submetidos a cirurgias para correção de estrabismo e identificar possíveis fatores de risco associados a tal ocorrência. MÉTODOS: Foi realizado estudo retrospectivo de 819 pacientes portadores de estrabismo submetidos à cirurgia para correção do desvio ocular entre janeiro de 1995 e dezembro de 2005 no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo. Os pacientes foram divididos em quatro grupos quanto ao tipo de desvio pré-operatório (esotropia alternante, esotropia monocular, exotropia alternante e exotropia monocular) e as variações no posicionamento ocular foram quantificadas em cada grupo. RESULTADOS: A prevalência de variações no posicionamento ocular (pós-operatório) maiores que 10∆ entre o total de pacientes estudado foi de 33,5% (274 pacientes). Entre estes, foi verificada maior frequência de desvios no sentido exotrópico (178 pacientes ou 65,0%) do que no sentido esotrópico (96 pacientes ou 35,0%), diferença esta que foi estatisticamente significativa (teste do qui-quadrado; p

This article presents the experience of its authors regarding the basic principles that guide them in the surgical treatment of horizontal strabismus. It addresses subjects such as the surgical classification of strabismus, minimal conditions for surgical indication, ideal age for surgery, principles of operating on the extraocular musculature, muscle response to shortening and recession, and other aspects relevant to a successful treatment of this type of oculomotor disorders.

Objetive: Description of a clinical case of a child presenting Opitz syndrome, strabismus and other oculomotor disturbances. Case report: A 3-year-old child, with penoscrotal hypos-padia, bifid scrotum, micrognathy, high palate, proeminent forehead, low nasal bridge, hypertelorism, epicanthus, low-set ears, clinodactyly, bifid spine, delayed motor develop-ment and anteriorly placed anus as manifestations of the Opitz syndrome (OMIM *145410). He presented also an alternating esotropia with crossed fixation (Ciancia's syndrome), associated with manifestations of a bilateral Duane's syndrome and a vertical deviation (L/R), possibly due to dissociated actions between the RSR and the palpebral muscles of the right eye. The child died after a surgery for an anorectal reconstruction. Discussion: Although presenting ocular manifestations, there are no papers referring to the Opitz syndrome in ophthalmological publications. Those which mention strabismus have no proper descriptions of the ocular motility conditions. The present case showed important oculomotor dissociations, but their causes could not be clarified, due to the premature death of the child.

Objective To test the hypothesis that the extraocular muscles (EOMs) of patients with infantile nystagmus have muscular and innervational adaptations that may have a role in the involuntary oscillations of the eyes. Methods Specimens of EOMs from 10 patients with infantile nystagmus and postmortem specimens from 10 control subjects were prepared for histologic examination. The following variables were quantified: mean myofiber cross-sectional area, myofiber central nucleation, myelinated nerve density, nerve fiber density, and neuromuscular junction density. Results In contrast to control EOMs, infantile nystagmus EOMs had significantly more centrally nucleated myofibers, consistent with cycles of degeneration and regeneration. The EOMs of patients with nystagmus also had a greater degree of heterogeneity in myofiber size than did those of controls, with no difference in mean myofiber cross-sectional area. Mean myelinated nerve density, nerve fiber density, and neuromuscular junction density were also significantly decreased in infantile nystagmus EOMs. Conclusions The EOMs of patients with infantile nystagmus displayed a distinct hypoinnervated phenotype. This represents the first quantification of changes in central nucleation and myofiber size heterogeneity, as well as decreased myelinated nerve, nerve fiber, and neuromuscular junction density. These results suggest that deficits in motor innervation are a potential basis for the primary loss of motor control. Clinical Relevance Improved understanding of the etiology of nystagmus may direct future diagnostic and treatment strategies.

The authors report a case of a 56-year-old woman with high myopia and a very pronounced restrictive progressively developed eso- and hypotropia. The surgical access to the complete section of the medial rectus muscle was easily obtained by a transcaruncular orbitotomy, not only because of the impossibility of using conventional techniques but also because the scleral rupture becomes highly risky in such cases. The lateral rectus was resected and reinserted above its original path, after being found in the inferotemporal quadrant of the eye. The immediate surgical result (an exotropia of about 12D) was considered a very good outcome, since such deviations tend to recur.

Homem de 25 anos apresentou diplopia em todas as posições do olhar, associada à movimentação ocular dolorosa, após sofrer traumatismo contuso em região orbitária direita. Tomografia computadorizada revelou fratura isolada indireta de parede medial de órbita direita. A correção cirúrgica da fratura levou ao desaparecimento da queixa de diplopia e melhorou o campo de visão binocular.

Strabismus is a common disorder of ocular alignment occurring in 2% to 5% of the children in the United States.1,2 Many patients can be managed medically with eye patching and glasses, but a large percentage require surgical intervention over the course of their lifetimes. Strabismus surgery attempts to restore binocular alignment by altering relative extraocular muscle (EOM) length and mechanical advantage. For example, resection surgery involves removal of a portion of what is considered an underacting muscle, and the shortened muscle is sutured to its original site of insertion. By contrast, recession surgery involves moving the insertion of what is considered an overacting muscle to a position posterior to its original site of attachment to the sclera. A large proportion of strabismus surgeries fail. In companion studies of long-term follow-up of surgical outcomes in patients with either congenital esotropia or exotropia, more than 50% of both cohorts ultimately developed a misalignment of 10 prism diopters or more after the first surgery.3,4 In another study of surgical treatment for childhood esotropia, of the group that had been successfully aligned to within 10 prism diopters, 21% developed consecutive exotropia.5 In those patients who required multiple surgeries for successful alignment, the incidence of developing consecutive exotropia increased to 62%. The surgical failure rate is not surgeon or procedure based.6 One of the complexities in treating strabismus is that its etiology is not understood. Although risk factors associated with increased incidence of strabismus have been described,7 and several genes have been identified that cause rare forms of congenital cranial dysinnervation disorders,8 the underlying causes of the most common forms of strabismus are unknown. Recent studies examining muscles from patients with inferior oblique overaction, as defined by eye position in adduction, showed that the muscles had distinct histologic phenotypes. This finding suggests that there are likely to be multiple underlying causes of EOM dysfunction that are quite distinct from one another.9 Other studies demonstrate that the EOMs from strabismus patients appear to adapt to cues received from the ocular motor system in the brain that control their motor behavior,10,11 as their satellite cell populations are in a constant state of flux. These studies suggest that the EOMs react to surgical interventions and that these adaptations could be assessed and potentially manipulated with a goal of improved surgical outcomes. In a recent study, we examined the effect of resection surgery on adult rabbit EOMs.12 We found that this muscle-shortening procedure resulted in a significant increase in satellite cell activation and their rapid fusion into existing myofibers. This result was present in both the actively stretched, resected muscle and in its passively stretched, antagonist muscle. In the present study, two muscle adaptations to surgery were examined in detail: the expression patterns of the myosin heavy chain (MyHC) isoforms and the reactions of the muscle regenerative cells, the myogenic precursor cells. Changes in MyHC isoforms were examined in both treatment arms (recession versus tenotomy), as these changes are associated with control of muscle shortening velocity and fatigability. In addition, as a means of assessing the rate of myofiber remodeling, both Pax7-positive muscle precursor cells and dividing cells in the satellite cell position were quantified; these are standard methods used to identify this muscle-regenerating population.10–12 An understanding of how a surgically altered EOM adapts may suggest potential interventions that could prolong the positive effects of surgery or alternatively could suggest ways that these changes may be prevented or magnified in an effort to maximize surgical effectiveness.

Strabismus is a disorder of ocular alignment of unknown etiology.1,2 The lack of knowledge about its cause may explain, in part, why surgical correction of strabismus and the maintenance of adequate alignment and binocularity are so difficult.3,4 Although recent genetic analyses of incomitant strabismus disorders demonstrated that the genetic causes that underlie specific congenital cranial dysinnervation disorders, such as CFEOM1 and -2, are due to mutations in genes critical to development of ocular motor neurons and their axonal connections,5,6 we are still a long way from understanding the possible genetic factors that underlie the various forms of complex strabismus that occur in the absence of known structural brain anomalies. Recent evidence suggests that comitant horizontal strabismus, such as congenital or infantile esotropias and exotropias, can be found in distantly related members of the same family.7 The exotropias are oculomotor disorders in which there is an imbalance between an underactive medial rectus (MR) muscle and an overactive lateral rectus (LR) muscle. The surgical treatment can be achieved by a recession–resection procedure: the LR is recessed while the MR is resected. Congenital or infantile esotropias are convergent deviations, which usually need surgical procedures if angles of deviation are greater than 30 prism diopters. The realignment is obtained by weakening an “overactive” MR (recess procedure) associated or not with strengthening of an “underactive” LR (resection procedure), depending on the size of the deviation. In some cases, when the deviation is very big, even big recess procedures are not enough to realign the eyes. In these situations, resections or marginal tenotomies are alternative techniques.8 The difficulty in producing a successful surgical outcome supports the idea that changes in the muscles themselves before, during, and after strabismus surgical corrections are performed are not well understood. Adult mammalian extraocular muscles (EOMs) express several characteristics that are not normally expressed in adult nonocular skeletal muscles. For example, myofibers of adult EOMs continue to express molecules such as the neonatal and developmental myosin heavy-chain isoforms,9 neural cell adhesion molecule,10 and a variety of muscle mitogens and growth factors.11,12 These molecules are normally downregulated in mature limb skeletal muscle, where they are usually associated only with skeletal muscle development or regeneration. Normal adult EOMs, unlike limb skeletal muscle, continuously remodel individual myofibers throughout life.13,14 In the unperturbed EOMs of adult humans, there is also a small percentage of activated satellite cells, the regenerative cell population found in skeletal muscle, positive for the myogenic lineage-specific marker MyoD.15 This suggests that this process of myofiber remodeling occurs in human EOMs as well. MyoD is expressed in both activated satellite cells and myoblasts but not in myotubes, mature myofibers,16,17 or quiescent satellite cells.18 Based on these data, our objectives were to determine whether the MR muscles of patients with a history of MR underaction or overaction show alterations in the process of satellite cell activation when compared to normal age-matched control muscles.