VOLUME 82 - ISSUE 2

Purpose: To estimate the prevalence of blindness and visual impairment in older adults living in Guatemala.
Methods: Participants ≥50 years of age were selected using random cluster sampling and evaluated using the Rapid Assessment of Avoidable Blindness method. Visual acuity was measured, and the lens was examined. If presenting visual acuity was <20/60, it was also tested with a pinhole and fundoscopy was performed. Blindness and visual impairment were classified as moderate visual impairment (presenting visual acuity <20/60 to 20/200), severe visual impairment (presenting visual acuity <20/200 to 20/400), or blindness (presenting visual acuity <20/400). The primary cause of blindness or visual impairment in each eye was determined, and if the cause was cataracts, the barriers to treatment were assessed.
Results: The study included 3,850 people ≥50 years of age, of whom 3,760 (97.7%) were examined. The age- and sex-adjusted prevalence of blindness was 2.9% (95% confidence interval, 2.0%-3.8%), while 5.2% (4.0%-6.4%) presented with severe visual impairment, and 27.6% (23.3%-32.0%) presented with moderate visual impairment. Cataracts were the leading cause of blindness (77.6%), followed by other posterior segment diseases (6.0%). Cataracts caused 79.4% of cases of severe visual impairment, while uncorrected refractive errors caused 67.9% of cases of moderate visual impairment. Following cataract surgery, 75% of participants had a presenting visual acuity of 20/200 or better, and in 19.0% of participants, visual acuity was not better than 20/200 with correction. Cost was the main barrier to cataract surgery (56.7%).
Conclusions: The prevalence of blindness in older adults is higher in Guatemala than in most Central American countries. Most cases of blindness and visual impairment were either preventable or treatable. Increased availability of affordable, high-quality cataract treatment would have a substantial impact on blindness prevention.

Keywords: Blindness/epidemiology; Prevalence; Vision, low/epidemiology; Cataract extraction

Purpose: To evaluate the clinical and surgical impacts of phenomena that could occur in intermittent exotropia.
Methods: The medical records of intermittent exotropia cases from 1991 to 2014 were retrospectively reviewed. All patients underwent a series of measures, including a protocol to assess monocular occlusion based on the propedeutics proposed by Kushner.
Results: Outdoor sensitivity was observed in 31% of patients with an undercorrection rate of 44% vs. 18% of cases with no outdoor sensitivity. After 1 h of monocular occlusion, 41% of all patients achieved an increase in deviation with an undercorrection rate of 40%, whereas 25% did not.
Conclusion: The results show the importance of complete propedeutics, since there is a higher rate of late undercorrection in cases with outdoor sensitivity and increased deviation after occlusion.

Keywords: Exotropia; Strabismus; Oculomotor muscles; Sensory deprivation; Vision, monocular

Purpose: To report our initial experience in the treatment of Acanthamoeba keratitis with accelerated corneal collagen cross-linking.
Methods: Retrospective chart review of patients diagnosed with Acanthamoeba keratitis with progressive corneal melting who were treated with accelerated collagen cross-linking.
Results: A total of 6 eyes (5 patients) were reviewed. All the patients received adjuvant therapy with moxifloxacin and chlorhexidine. In 4 cases, the ulcer healed with a mean interval to epithelialization of 108.8 days (range 59-217). In 2 eyes, there was a persistent neurotrophic ulcer. The melting was not progressive in any case, nor did any eye required emergency penetrating keratoplasy.
Conclusion: This study suggests a beneficial effect of accelerated collagen cross-linking in cases of Acanthamoeba keratitis with corneal melting. Thus, collagen cross-linking may be considered as adjuvant treatment for Acanthamoeba keratitis.

Keywords: Cross-linking reagents; Acanthamoeba keratitis; Corneal ulcer; Collagen

Purpose: To evaluate the first three years of The Amazon Ocular Oncology Center, the first ocular cancer center in the North of Brazil.
Methods: Here, we report patient information including patients’ age, gender, diagnosis, treatment, and city of origin.
Results: Two hundred and twenty-one patients were included on this study: 160 (72%) patients came from the city of Manaus, 52 (24%) from other cities in Amazonas, and 9 (4%) from other states. Of the 221 patients, 150 (68%) were afflicted with benign lesions and the remaining 71 (32%) had malignant lesions. Benign diagnosis included pterygium, chalazium, conjunctival nevus, and papilloma, cataract, and retinal detachment. Of the malignant cases, squamous cell carcinoma (SCC) of the conjunctiva was the most frequent with 43 cases (60%). Other diagnoses included choroidal melanoma (8 cases, 11%), retinoblastoma (7 cases, 9%), lymphomas (5 cases, 7%), basal cell carcinomas of the eyelid (4 cases, 5%), conjunctival melanoma (2 cases, 2%), and Kaposi sarcomas (1 case, 1%). Of the 43 patients with SCC, the mean age was 62 years old, and 30 (69%) were male; 29 patients (67%) were treated with an excisional biopsy, and 14 (33%) were treated with neoadjuvant topic chemotherapy, followed by surgery.

Keywords: Eye/pathology; Eye neoplasms; Carcinoma; Melanoma; Medical oncology; Amazon

Purpose: To assess the efficacy of using a nonsteroidal anti-inflammatory drug preoperatively and of applying the re-dilation technique when necessary to minimize pupil size variation when comparing the degree of mydriasis before femtosecond laser pretreatment with that at the beginning of phacoemulsification.
Methods: This retrospective study included patients who underwent cataract surgery using the LenSx (Alcon Laboratories, Inc., Fort Worth, TX). Our routine dilating regimen with flurbiprofen, tropicamide, and phenylephrine was used. The re-dilation technique was applied on eyes that manifested with a pupillary diameter that was smaller than the programmed capsulotomy diameter after laser pretreatment. The technique consists of overcoming pupillary contraction by instilling tropicamide and phenylephrine before phacoemulsification. Pupil size was assessed before femtosecond laser application and at the beginning of phacoemulsification.
Results: Seventy-five eyes (70 patients) were included. Nine (12%) eyes underwent the re-dilation technique. There was no significant difference in mean pupillary diameter and mean pupillary area between the two studied surgical time points (p=0.412 and 0.437, respectively). The overall pupillary area constriction was 2.4 mm². Immediately before opening the wounds for phacoemulsification, none of the eyes presented with a pupillary diameter <5 mm, and 61 (85.3%) eyes had a pupillary diameter >6 mm.
Conclusion: Preoperative administration of nonsteroidal anti-inflammatory drug and the re-dilation technique resulted in no significant pupil size variation in eyes that were pretreated with the femtosecond laser, when comparing the measurements made before the laser application and at the beginning of phacoemulsification. This approach can avoid the need to proceed with cataract extraction with a constricted pupil.

Keywords: Cataract extraction; Preoperative period; Laser therapy; Intraoperative complications; Miosis; Nonsteroidal anti-inflammatory drugs

Purpose: To assess the compliance, efficacy, and safety of the long-term use of topical tacrolimus for the clinical management of vernal keratoconjunctivitis.
Methods: The medical records of patients with vernal keratoconjunctivitis undergoing long-term treatment with 0.03% topical tacrolimus were retrospectively reviewed. The duration of tacrolimus use and the causes for drug discontinuation were used to assess treatment compliance. To assess drug efficacy, the need for and the number of times that topical corticosteroids were used to control symptoms were registered. Side effects related to tacrolimus use were monitored to determine drug safety.
Results: The study cohort consisted of 21 patients who met the eligibility criteria. The mean duration of tacrolimus use was 41.3 ± 18.5 months. Fourteen patients (66.7%) continuously used tacrolimus, and three (14.3%) discontinued treatment following complete remission. Four patients (19%) did not use tacrolimus as prescribed or interrupted tacrolimus use on their own: two (9.5%) because of discomfort upon application and two (9.5%) because of the lack of improvement. Ten patients (47.6%) maintained disease control without the use of corticosteroids, whereas 11 (52.4%) required an average of 2.70 ± 1.35 corticosteroid cycles to control symptoms. The only reported side effect was discomfort upon application.
Conclusions: Despite the small sample size and study design limitations, these results support the long-term use of topical tacrolimus as an effective and safe option for the treatment of vernal keratoconjunctivitis, with good compliance of patients to the treatment.

Keywords: Cornea, Vernal keratoconjunctivitis, Tacrolimus, Allergic conjunctivitis, Antiallergic drugs

Purpose: To compare the choroidal thickness in active and stable phases of thyroid eye disease.
Methods: Forty-seven eyes of 47 patients with thyroid eye disease were prospectively studied. Patients were evaluated on the basis of their clinical activity scores, with scores ≥3 defined as active disease. Subfoveal, temporal macular, nasal macular, temporal peripapillary, and nasal peripapillary choroidal thickness measurements were performed with Cirrus enhanced depth imaging spectral-domain optical coherence tomography, and the results in the two groups were compared.
Results: Twenty-four patients were int he active group, whereas 23 patients were in the stable group. Choroidal thickness was significantly higher in the subfoveal and temporal macular regions in the active group. Although the nasal macular and peripapillary values were also higher in the active group, the difference was insignificant.
Conclusions: Subfoveal choroidal thickness was significantly higher in patients with thyroid eye disease in the active phase than in those with stable phase disease.

Keywords: Graves ophthalmopathy; Choroid/anatomy & histology; Tomography, optical coherence

Purpose: To determine the reliability of swept-source optical coherence tomography in cases in which soft contact lenses cannot be removed when acquiring biometric measurements.
Methods: Eight subjects were included and only one eye per participant was analyzed. Each eye was measured six times by swept-source optical coherence tomography with the IOLMaster 700 instrument (Carl Zeiss Meditec, Jena, Germany). Axial length, central corneal thickness, anterior chamber depth, lens thickness, and keratometric measurements were evaluated for the naked eye and while wearing soft contact lenses of three different powers (-1.5, -3.0, and +2.0 D).
Results: There were statistically significant changes in axial length, central corneal thickness, anterior chamber depth, and keratometric measurements with soft contact lenses as compared to the naked eye (p<0.001). However, there were no significant differences in lens thickness outcomes between the naked eye and while wearing the three soft contact lenses (p>0.5). The changes in axial length, central corneal thickness, and anterior chamber depth were lens-specific and dependent on the thickness of the lens used.
Conclusions: Sept-source optical coherence tomography based lens thickness measurements while wearing soft contact lenses are comparable to those of the naked eye. However, the thickness and the optical design of the soft contact lens may lead to significant differences in the axial lengh, central corneal thickness, anterior chamber deph, and keratometric measurements.

Keywords: Tomography, optical coherence; Contact lenses; Biometry

Purpose: We aimed to compare the aqueous humor total oxidant status, total antioxidant capacity, and levels of interleukin-6 and vascular endothelial growth factor between patients with diabetic retinopathy and controls and to correlate these levels with the DR status.
Methods: Patients who underwent cataract surgery were enrolled. The first group (control group) comprised patients without diabetes; the second group comprised diabetic patients without retinopathy; the third group comprised patients with nonproliferative diabetic retinopathy; and the fourth group comprised patients with proliferative diabetic retinopathy. All patients underwent full ophthalmologic examination before cataract surgery. Prior to surgery, samples of aqueous humor sampling were obtained and stored at -80 °C. Total antioxidant capacity, total oxidant status, and levels interleukin-6 and vascular endothelial growth factor were investigated in these samples and correlated with diabetic retinopathy status.
Results: This study analyzed 86 pairs of eyes of 86 patients. All groups were statistically similar in age and sex, but the total antioxidant capacity was lowest in patients with proliferative diabetic retinopathy. Moreover, the total oxidant status and levels of vascular endothelial growth factor and interleukin-6 were found to slightly increase according to the retinopathy status.
Conclusion: Oxidative stress, interleukin-6, and vascular endothelial growth factor in the aqueous humor seem to play important roles in the pathogenesis of diabetic retinopathy, especially in the proliferative type.

Keywords: Diabetic retinopathy; Oxidative stress; Interleukin-6; Vascular endothelial growth factor A; Aqueous humor

Purpose: We aimed to compare the body mass index and vitamin and mineral status of children with and without amblyopia.
Methods: Amblyopic children aged between 5 and 18 years (n=46) and age-matched control children (n=32) were evaluated in terms of anthropometric parameters, including height, weight, body mass index and demographic features. Serum vitamin B₁₂ and folate were measured using an Advia Centaur XP (Siemens, Ireland) biochemistry analyzer. We evaluated the inorganic mineral elements from hair samples with inductively coupled plasma-mass spectrometry using a Thermo XSeries 2 analyzer (Thermo Fisher Scientific, Bremen, Germany).
Results: No significant difference was found between the two groups in terms of height, weight, and body mass index or serum B₁₂ and folate concentrations (p>0.05). Children with severe amblyopia had lower vitamin B₁₂ and folate and higher body mass index. The levels of phosphorus (p=0.012), selenium (p=0.002), molybdenum (p<0.001), iodine (p=0.002), chromium (p=0.022), boron (p<0.001), and beryllium (p=0.005) were all significantly lower in the amblyopia group compared to the control group. All of these minerals, except phosphorus, were also significantly lower in those with severe amblyopia compared to those with milder amblyopia and controls (p<0.05).
Conclusion: Amblyopic children are significantly deficient in some inorganic elements. Inorganic elements, vitamin B₁₂, and folate may play an important role in the visual development of amblyopic children.

Keywords: Amblyopia; Body mass index; Vitamin B₁₂; Folate; Humans; Child; Adolescent

Capsular block syndrome is a rare complication of phacoemulsification surgery with continuous curvilinear capsulorhexis and intraocular lens implantation. Here, we report a case of very late-onset capsular block syndrome that developed 13 years after cataract extraction and present the surgical approach used for its successful treatment.

Keywords: Phacoemulsification/adverse effects; Lens implantation, intraocular/adverse effects; Cataract extraction/adverse effects; Lens, capsule; Capsulorhexis

We describe here a case of a 21-year-old woman who presented with low visual acuity, pain, and hyperemia in the left eye for 45 days. Her eye had extensive corneal infiltrate, with melting and a central perforation that was glued with cyanoacrylate, but with Seidel (+). She underwent tectonic corneal transplantation, and anterior chamber lavage with subconjunctival infiltration with voriconazole, as well as intracameral injections of amphotericin B. Laboratory tests revealed Paecilomyces lilacinus as the infectious agent. The patient was then maintained with oral voriconazole and eye drops for three months, after which the infection was considered cured. However, in the sixth postoperative month she presented with endothelial rejection, and two weeks later signs of recurrence of the fungal infection. She was treated with two further washes of the anterior chamber and subconjunctival injection of voriconazole, followed by intravenous voriconazole that was replaced with drops after ten days. The infection initially worsened, but then regressed, and at last follow-up, the patient was still infection-free.

Keywords: Keratitis/drug therapy; Eye infections, fungal/drug therapy; Paecilomyces lilacinus; Anterior chamber; Therapeutic irrigation; Voriconazole/therapeutic use

Numerous studies have reported on structural vascular anomalies and ischemia associated with neurofibromatosis type 1 that are thought to stem from dysfunction of neurofibromin, the neurofibromatosis type 1 protein. Documented cases of associated antiphospholipid syndrome fulfilling the accepted diagnostic criteria are exceptionally rare, with only three cases reported in the literature. Here, we report on a patient with neurofibromatosis type 1 and a history of spontaneous abortions presenting with sudden vision loss in the right eye and swelling of the optic nerve head. Fluorescein angiography indicated anterior ischemic optic neuropathy. Brain magnetic resonance imaging revealed findings consistent with left cavernous sinus meningioma. Serologic testing demonstrated persistently elevated anti-β₂-glycoprotein antibodies. Her findings suggested antiphospholipid syndrome with concomitant clinical and laboratory evidence of antiphospholipid syndrome: frequent abortions, a vaso-occlusive episode, and persistently elevated antiphospholipid syndrome antibodies. To our knowledge, this case represents the first neuro-ophthalmic manifestation of antiphospholipid syndrome associated with neurofibromatosis type 1.

Keywords: Neurofibromatosis type 1; NF1; Antiphospholipid syndrome; Fluorescein angiography; Case report

This report presents three patients diagnosed with macular dystrophies with variants in PRPH2. Peripherin-2, the protein of this gene, is important in the morphogenesis and stabilization of the photoreceptor outer segment. Peripherin-2 deficiencies cause cellular apoptosis. Moreover, pathogenic variants in PRPH2 are associated with various diseases, such as pattern, butterfly-shaped pattern, central areolar, adult-onset vitelliform macular, and cone-rod dystrophies as well as retinitis pigmentosa, retinitis punctata albescens, Leber congenital amaurosis, fundus flavimaculatus, and Stargardt disease.

Keywords: Retinal degeneration; Genotyping techniques; Vitelliform macular dystrophy; Retinitis pigmentosa; Genetics

This review aims to caution ophthalmologists about the ocular consequences leading to the diagnosis of hepatitis C virus infection. In addition, in this context, the effects of old and new drugs are discussed in the ophthalmological setting. The importance of early diagnosis and the curative treatment of the disease has been reported in the national and international literature, demonstrating that its progression has important implications for daily clinical and surgical ophthalmological practice. Despite the scarcity of studies on new direct-acting antiviral drugs, fewer side effects of these drugs have been shown when compared with conventional interferon treatment with or without ribavirin. The ophthalmologist’s risk of becoming infected, as demonstrated by the presence of the virus in ocular structures, and the possibility of contamination, is also discussed.

Keywords: Hepatitis C/ complications; Hepatitis C/drug therapy; Interferon/therapeutic use; Direct-acting antiviral drugs