An immunohistochemical study of the ‘snowbank’ in a case of pars planitis

Purpose: To characterize the extracellular matrix and cellular components of a ‘snowbank’ removed during vitreous surgery for treatment of retinal detachment complicating pars planitis. Methods: The ‘snowbank’ was examined using immunohistochemical techniques and a panel of monoclonal and polyclonal antibodies directed against glial fibrillary acidic protein (GFAP), cytokeratin, alpha smooth muscle actin, tenascin, laminin, fibronectin, and collagen types I, II, and III. Results: The ‘snowbank’ was acellular except on the uveal side where there were cytokeratin-positive retinal pigment epithelial cells. There were no cells positive for the glial cell marker GFAP and the myofi- broblast cell marker alpha smooth muscle actin. The extracellular matrix of the ‘snowbank’ contained tenascin and collagen types I, II, and III. There was no immunoreactivity for laminin and fibronectin. Conclusion: These results on the immunohistochemical components of the ‘snowbank’ may be useful in clarifying the nature of the chronic inflammatory process in pars planitis. They indicate extensive tissue repair and remodeling, leading to major loss of function.     

The problem of trachoma within an onchocerciasis-endemic zone in Kaduna: need for a multilateral approach?

INTRODUCTION: Within the mesoendemic onchocerciasis belt of Kaduna State, Northern Nigeria, there were other causes of ocular morbidity as well. We investigated the contribution of trachoma. METHODS: A total of 6831 individuals were examined for eye disease, including signs of trachoma. RESULTS: The overall prevalence of trachoma was 4.5% (577 eyes of 310 individuals), making it the second most common cause (1 in 5) of ocular morbidity after cataracts. Of the 577 eyes, 405 (70.2%) had cicatrizing disease while the rest had active disease. Overall, the prevalence of TF was 1.1% (1.3% in those < 10 years of age), TI 0.2%, TS 3%, CO 0.5% and TT 1.1% (4.3% and 3.5% in subjects aged > 55 and > 40 years, respectively). The prevalence of trachoma increased with age. The overall prevalence of blindness in the whole population was 2.7%. Trachoma accounted for 11% of this. On the other hand, onchocerciasis accounted for 3.1% of the overall ocular morbidity (less than trachoma) and 39% of the blindness. CONCLUSIONS: There appears to be a clear need to retrain middle cadre ivermectin workers in trachoma rapid assessment and SAFE strategy intervention methods in order to further impact blindness prevention in these 'onchocerciasis-endemic' zones.     

Risk factors for exudative age-related macular degeneration in a large French case–control study

Purpose

The purpose of the CAP (Creteil AMD PHRC-funded) Study was to analyze risk factors of exudative age-related macular degeneration (AMD) in a large French case–control population.

Patients and methods

One thousand and twenty-four patients with exudative AMD and 275 controls were recruited. Information about lifestyle, medical history, and dietary intake were collected. Associations of risk factors were estimated using logistic regression.

Results

After multivariate adjustment, CFH Y402H and ARMS2 A69S polymorphisms were associated with very high risk for exudative AMD (OR?=?6.21 and OR?=?11.7, respectively, p?<?0.0001). Risk for exudative AMD was increased in current smokers (OR?=?3.79, p?=?0.0003) and former smokers having quitted since less than 20 years ago (OR?=?2.30, p?=?0.002), but not in former smokers having quitted since 20 years or more ago (OR?=?0.81, p?=?0.43). Heavy smokers (at least 25 pack-years) were particularly at risk (OR?=?3.61, p?<?0.0001). Use of cooking oils rich in omega 3 fatty acids was significantly associated with a reduced risk of exudative AMD (OR?=?0.55, 95 % CI: 0.36–0.84, p?=?0.006), as well as a high consumption of fruits (OR?=?0.60, 95 % CI: 0.37–0.98, p?=?0.04), but not the consumption of fish, vegetables or oils rich in omega 6. High waist circumference was associated with increased risk for exudative AMD (OR?=?2.53, p?<?0.0001), but not hypercholesterolemia, hypertension, or body mass index.

Conclusions

The CAP Study confirms major genetic risk factors for exudative AMD. It further documents the high risk in heavy smokers and the long persistence of risk after smoking cessation, and the associations with waist circumference and fruit consumption. Furthermore, we observed an inverse correlation between AMD and cooking oils harboring a beneficial omega-3 fatty acid profile.     

Objective structured clinical examination for undergraduates: Is it a feasible approach to standardized assessment in India?

Background:

There has been a growing concern among medical educators about the quality of medical graduates trained in various medical colleges in our country. Data based on the faculty and student perceptions of undergraduate curriculum indicate a need for laying more stress on practical skills during their training and assessment. The Objective Structured Clinical Examination (OSCE) is a reliable and an established and effective multistation test for the assessment of practical skills in an objective and a transparent manner. The aim of this article is to sensitize universities, examiners, organizers, faculty, and students across India to OSCE.

Materials and Methods:

We designed an assessment based on 22-station OSCE and administered it to 67 students during their final year, integrating all the domains of learning, that is higher order cognitive domain, psychomotor domain, and affective domain. Data analysis was done using SPSS version 15.

Results:

The OSCE was feasible to conduct and had high perceived construct validity. There was a significant correlation between the station score and total examination score for 19 stations. The reliability of this OSCE was 0.778. Both students and faculty members expressed a high degree of satisfaction with the format.

Conclusion:

Integrating a range of modalities into an OSCE in ophthalmology appears to represent a valid and reliable method of examination. The biggest limitation with this format was the direct expenditure of time and energy of those organizing an OSCE; therefore, sustaining the motivation of faculty might pose a challenge.     

Using a botuline toxin diagnostic test in a case of bilateral stilling--Türk--Duane (STD) syndrome found during preparation for cataract surgery

PURPOSE: The presentation of complex procedures in preoperative diagnosis, allowing the evaluation of reaction of a patient with bilateral STD syndrome, to a potential change in the long-lasting ocular motility disturbances and corrective head position. MATERIAL AND METHODS: The botuline toxin was injected into the medial rectus muscle of the eye with greater motility disturbance in convergent strabismus. It was discovered during preparation for cataract surgery in a 45 years old female with STD Syndrome I type. Due to reduced visual acuity the diagnosis of binocular vision were performed after bilateral cataract surgery. We were afraid that the fixed sensory status of the patient would change, and therefore we performed botuline injections. Strabismus angle, ocular motility and diplopia were assessed and compared. RESULTS: The reduction of strabismus angle was achieved with no diplopia. The patient no longer needed the corrective head position, with binocular vision present while looking straight ahead. Also, a slight improvement was obtained in the abduction motility of the eye to which botuline toxin was injected. CONCLUSION: Preoperative diagnostic botuline toxin injection into the rectus medial muscle of the eye with greater motility disturbance, gives an effect of strabismus reduction. This allows for further decisions of whether, and what type of surgical treatment should be performed.     

Is glaucoma blindness a disease of deprivation and ignorance? A case–control study for late presentation of glaucoma in India

Aim:

The aim was to identify the presenting symptoms and social risk factors for late presentation of primary glaucoma in newly diagnosed cases.

Materials and Methods:

It was a case-control study in a tertiary eye care center in Maharashtra, India. Newly diagnosed patients with primary glaucoma were classified as cases (late presenters) where there was no perception of light in one eye or severe visual field loss affecting an area within 20° of fixation or a cup–disc (C:D) ratio ≥0.8 and controls (early presenters), presenting relative scotoma within 20° of fixation or a C:D ratio <0.8, but >0.5. All patients underwent a comprehensive ocular examination including gonioscopy, perimetry, and detailed family and social history. Occupation, education, and socioeconomic status were graded. SPSS version 12.0 was used, and univariate and multivariate logistic regression analysis was performed.

Results:

Gradual progressive painless loss of vision was the commonest symptom (175, 87.5%). Primary angle closure glaucoma was more common in females (P = 0.001) and lower socioeconomic groups (P = 0.05). Patients who were less educated were more likely to have late presentation of glaucoma (P < 0.001, odds ratio = 0.07; 95% CI, 0.02–0.25). Knowledge of family history of glaucoma (P = 0.80, odds ratio = 1.16; 95% CI, 0.36–3.71) and eye clinic attendance in past 2 years still resulted in late presentation (P = 0.45, odds ratio = 1.34, 95% CI, 0.63–2.82).

Conclusion:

Lack of education and awareness of glaucoma were major risk factors for late presentation.     

Abnormal systemic and ocular vascular response to temperature provocation in primary open-angle glaucoma patients: a case for autonomic failure?

PURPOSE: To assess systemic and ocular vascular reactivity in response to warm and cold provocation in untreated patients with primary open-angle glaucoma and normal control subjects. METHODS: Twenty-four patients with primary open-angle glaucoma and 22 normal control subjects were subjected to a modified cold pressor test involving immersion of the right hand in 40 degrees C warm water followed by 4 degrees C cold water exposure, and finger and ocular blood flow were assessed by means of peripheral laser Doppler flowmetry and retinal flowmetry, respectively. Finger and body temperature as well as intraocular pressure, systemic blood pressure, systemic pulse pressure, heart rate, and ocular perfusion pressure were also monitored. RESULTS: The patients with glaucoma demonstrated an increase in diastolic blood pressure (P = 0.023), heart rate (P = 0.010), and mean ocular perfusion pressure (P = 0.039) during immersion of the tested hand in 40 degrees C water. During cold provocation, the patients demonstrated a significant decrease in finger (P = 0.0003) and ocular blood flow (the parameter velocity measured at the temporal neuroretinal rim area; P = 0.021). Normal subjects did not demonstrate any blood flow or finger temperature changes during immersion of the tested hand in 40 degrees C water (P > 0.05); however, they exhibited increases in systolic blood pressure (P = 0.034) and pulse pressure (P = 0.0009) and a decrease in finger blood flow (P = 0.0001) during cold provocation. In normal subjects, the ocular blood flow was unchanged during high- and low-temperature challenge. CONCLUSIONS: Cold provocation elicits a different blood pressure, and ocular blood flow response in patients with primary open-angle glaucoma compared with control subjects. These findings suggest a systemic autonomic failure and ocular vascular dysregulation in POAG patients.     

Anti-vascular endothelial growth factor treatment for choroidal neovascularization secondary to angioid streaks in pseudoxanthoma elasticum：a case report and systemic review

The present study reports a case of a patient with choroidal neovascularization (CNV) associated with pseudoxanthoma elasticum (PXE). We observed the functional and anatomical improvement of the patient treated with intravitreal vascular endothelial growth factor (VEGF) inhibitor bevacizumab. The study also systematically searched the database for similar cases to provide a literature review. Data concerning the clinical features, treatment strategies and outcomes were extracted and analyzed. Retrospective interventional case report and systematic literature review. A 56-year-old healthy Chinese woman with CNV secondary to PXE was reported. Examinations included best corrected visual acuity (BCVA), biomicroscopy, optical coherence tomography (OCT), lfuorescein and indocyanine green angiography and digital fundus photography. The patient managed with intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections (bevacizumab 1.25 mg/0.05 mL). The Cochrane Library, PubMed, OVID, and UpToDate databases were searched using the term pseudoxanthoma elasticum or Gr?nblad-Strandberg syndrome with the limits English. Articles that predated the databases were gathered from current references. Fundus examination revealed angioid streaks bilaterally and CNV in left eye (LE). After the patient underwent three intravitreal injections of bevacizumab, the LE showed absorption of the subretinal lfuid and shrinkage of the CNV. Visual acuity (VA) was improved in her treated LE. Bevacizumab treatment was well tolerated with no adverse events reported. Approximately ten articles about 45 patients (49 eyes) describing CNV secondary to angioid streaks in PXE treated with anti-VEGF were found in the literature search. In the present case, bevacizumab of an initial three injection loading dose, achieved maintenance of visual function in the treatment of CNV associated with angioid streaks in PXE. Literature articles concluded that the intravitreal application of anti-VEGF is highly efifcient for improving and stabilizing the lesion as well as the eyesight. So we believe that anti-VEGF therapy can be a great choice of treatment for CNV secondary to angioid streaks related PXE.     

A systematic review on ‘Foveal Crowding’ in visually impaired children and perceptual learning as a method to reduce Crowding

Background

This systematic review gives an overview of foveal crowding (the inability to recognize objects due to surrounding nearby contours in foveal vision) and possible interventions. Foveal crowding can have a major effect on reading rate and deciphering small pieces of information from busy visual scenes. Three specific groups experience more foveal crowding than adults with normal vision (NV): 1) children with NV, 2) visually impaired (VI) children and adults and 3) children with cerebral visual impairment (CVI). The extent and magnitude of foveal crowding as well as interventions aimed at reducing crowding were investigated in this review. The twofold goal of this review is : [A] to compare foveal crowding in children with NV, VI children and adults and CVI children and [B] to compare interventions to reduce crowding.

Methods

Three electronic databases were used to conduct the literature search: PubMed, PsycINFO (Ovid), and Cochrane. Additional studies were identified by contacting experts. Search terms included visual perception, contour interaction, crowding, crowded, and contour interactions.

Results

Children with normal vision show an extent of contour interaction over an area 1.5?C3× as large as that seen in adults NV. The magnitude of contour interaction normally ranges between 1?C2 lines on an acuity chart and this magnitude is even larger when stimuli are arranged in a circular configuration. Adults with congenital nystagmus (CN) show interaction areas that are 2× larger than those seen adults with NV. The magnitude of the crowding effect is also 2× as large in individuals with CN as in individuals with NV. Finally, children with CVI experience a magnitude of the crowding effect that is 3× the size of that experienced by adults with NV.

Conclusions

The methodological heterogeneity, the diversity in paradigms used to measure crowding, made it impossible to conduct a meta-analysis. This is the first systematic review to compare crowding ratios and it shows that charts with 50% interoptotype spacing were most sensitive to capture crowding effects. The groups that showed the largest crowding effects were individuals with CN, VI adults with central scotomas and children with CVI. Perceptual Learning seems to be a promising technique to reduce excessive foveal crowding effects.     

Clinicopathological analysis of 719 pediatric and adolescents’ ocular tumors and tumor-like lesions: a retrospective study from 2000 to 2018 in China

AIM: To analyze the retinal proteomes with and without conbercept treatments in mice with oxygen-induced retinopathy (OIR) and identify proteins involved in the molecular mechanisms mediated by conbercept. METHODS: OIR was induced in fifty-six C57BL/6J mouse pups and randomly divided into four groups. Group 1: Normal17 (n=7), mice without OIR and treated with normal air. Group 2: OIR12/EXP1 (n=14), mice received 75% oxygen from postnatal day (P) 7 to 12. Group 3: OIR17/Control (n=14), mice received 75% oxygen from P7 to P12 and then normal air to P17. Group 4: Lang17/EXP2 (n=21), mice received 75% oxygen from P7 to P12 with intravitreal injection of 1 μL conbercept at the concentration of 10 mg/mL at P12, and then normal air from P12 to P17. Liquid Chromatography-Mass Spectrometry (LC-MS)/MS data were reviewed to find proteins that were up-regulated after the conbercept treatment. Gene ontology (GO) analysis was performed of conbercept-mediated changes in proteins involved in single-organism processes, biological regulation, cellular processes, immune responses, metabolic processes, locomotion and multiple-organism processes. RESULTS: Conbercept induced a reversal of hypoxia-inducible factor 1 signaling pathway as revealed by the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and also induced down-regulation of proteins involved in blood coagulation and fibrin clot formation as demonstrated by the Database for Annotation, Visualization and Integrated Discovery (DAVID) and the stimulation of interferon genes studies. These appear to be risk factors of retinal fibrosis. Additional conbercept-specific fibrosis risk factors were also identified and may serve as therapeutic targets for fibrosis. CONCLUSION: Our studies reveal that many novel proteins are differentially regulated by conbercept. The new insights may warrant a valuable resource for conbercept treatment.     

Clinicopathological analysis of 719 pediatric and adolescents’ ocular tumors and tumor-like lesions: a retrospective study from 2000 to 2018 in China

AIM: To introduce a new surgical technique, air-bubble technique for the management of posterior capsule rupture (PCR) and to evaluate the safety and efficacy of the technique. METHODS: A retrospective case series analysis of 24 eyes of 24 patients, in which the air bubble technique was used for the management of PCR, was performed. Once PCR occured, a dispersive ophthalmic viscosurgical device (OVD) was injected into the tear. And small volumes (0.2-0.3 mL) of air bubbles were injected beneath the OVD. The air bubble served as a physical barrier and supported the posterior capsule. RESULTS: After surgery, none of the patients had serious complications during the follow-up period of 1y. Extension of the PCR size occured in only 2 cases, and additional OVD injection was required only in 3 cases. Air bubbles imparted great stability to the nuclear pieces and the posterior capsule. CONCLUSION: The air-bubble technique may be considered a safe and effective procedure for managing a PCR. It may be of value to the inexperienced cataract surgeon.     

An open-label,prospective, single-arm study of switching from infliximab to cyclosporine for refractory uveitis in patients with Behçet’s disease in long-term remission

Purpose

Although infliximab (IFX) decreases the risk of blindness due to refractory uveitis in patients with Behçet's disease (BD), there are no standard criteria for IFX switching or withdrawal. To evaluate the effect of IFX switching in patients with BD in long-term remission, a prospective, single-arm intervention trial was conducted, switching from IFX to cyclosporine A (CYA).

Study design

A prospective open-label study.

Methods

Eligible patients met the following criteria: administration of IFX without concomitant immunosuppressants for more than 5 years with no episodes of ocular attacks, no retinal vasculitis on fluorescein fundus angiography, negative C-reactive protein in serum, and no extraocular lesions at the time of IFX withdrawal. CYA 5 mg/kg/day was administered from 6 weeks after IFX withdrawal. The primary outcome was the rate of readministration of tumor necrosis factor inhibitors at 1 year after IFX withdrawal.

Results

Three of 45 BD patients treated with IFX for refractory uveitis were included in the study. At 1 year after withdrawal of IFX, no patient had experienced any ocular attacks or needed readministation of IFX. However, extraocular lesions, such as recurrent oral ulcers, folliculitis, and recurrent fevers, occurred in all patients. Liver or renal dysfunction, which may have been caused by CYA, was also observed in all patients.

Conclusions

Although no ocular attacks were observed for at least 1 year after IFX withdrawal, this prospective study indicates that IFX withdrawal should be considered carefully, even for patients in long term remission of ocular and extraocular lesions.

     

Prevalence of buried probe in complex congenital nasolacrimal duct obstruction and evaluation of its success rate post ‘probing and irrigation’: a single-centre retrospective study

Introduction: The aim of this study was to determine the prevalence of buried probe variant of complex congenital nasolacrimal duct obstruction (CNLDO) and to evaluate the outcome of probing and irrigation in such cases. Institutional review board approval was taken.

Material & Methods: A total of 309 eyes (258 patients) were diagnosed with CNLDO during the study period of January 2014–March 2017. A retrospective file review of 25 lacrimal systems of 20 patients diagnosed as buried probe variant of complex CNLDO was carried out during the study period.

Result: Buried probe variant of complex CNLDO was found to be 8% of the total CNLDO cases during the study period. Mean age at presentation was 1.7 years (range 8–48 months). Discharge and matting of eyelashes were the presenting symptoms in 22 out of 25 (88%) cases, whereas the only epiphora was the presenting symptom in three (12%) cases. Regurgitation of mucopurulent discharge on pressure over lacrimal sac area was positive in 16 out of 25 (64%) eyes. Associated lacrimal and nasal pathologies were seen in six out of 25 cases (24%).

Success rate in buried probe variant cases of CNLDO in our study at 3-month follow-up was 88% (22 of 25 cases).

Conclusion: A high period prevalence of 8% out of all CNLDO cases in our study suggests that the buried probe should be considered in selective cases of CNLDO and earlier unsuccessful probing.