Background
Systemic therapeutics targeting the peroxisome proliferator-activated receptors have been found to be beneficial in the treatment of diabetic retinopathy. In this paper, we provide a rationale for the use of these therapeutics as intraocular agents. In addition, we introduce the peroxisome proliferator-activated receptors and describe their functions in response to the drugs.
Discussion
Based on the evidence of large-scale clinical studies investigating the systemic administration of fenofibrate, this ligand for peroxisome proliferator-activated receptor-α is potentially a good candidate for intraocular delivery. Here, we describe the mechanisms by which it might be acting to improve diabetic retinopathy, its relative safety and we speculate on how it could be developed for intraocular delivery.
Summary
In this paper, we provide a rationale for the further investigation of peroxisome proliferator-activated receptor-α agonists as intraocular agents for the treatment of diabetic retinopathy.
doi:10.1186/1471-2415-12-46
PMCID: PMC3532122
PMID: 22937835
Diabetes; Diabetic retinopathy; Intraocular; Fenofibrate; TZDs; PPARs
Background
Schwannomas are slow-growing typically encapsulated tumors composed of differentiated Schwann cells, the primary class of peripheral glial cells. Complete excision is the treatment of choice for orbital schwannomas that cause pain, disfigurement, diplopia, or optic neuropathy. The presence of multiple schwannomas in a single patient suggests possible association with neurofibromatosis type 2 (NF2) or schwannomatosis.
Case presentation
We present 2 patients who experienced recurrent orbital schwannoma without evidence for neurofibromatosis. The recurrence in one patient, a 59-year old man, occurred 6 years after complete excision of the initial tumor. This recurrence consisted of 2 independent tumors in the same orbit. The recurrence in the second patient, a 5 year-old girl, occurred multiple times within days to weeks of partial excisions until eventually
a complete excision was performed.
Conclusion
The clinical history, histopathologic features and particularly the intraoperative findings suggest that the 59 year old man suffers from orbital schwannomatosis, while the rapid recurrence in the second patient correlated with the cellular features of her plexiform schwannoma. Hence, the recurrence in each patient is linked to a different etiology, with implications for treatment and patient counseling given the difficulty in treating orbital schwannomatosis. To our knowledge, this is the first description of isolated orbital schwannomatosis.
doi:10.1186/1471-2415-12-44
PMCID: PMC3503695
PMID: 22937797
Background
Glaucoma has been shown to lead to disability in many daily tasks including visual search. This study aims to determine whether the saccadic eye movements of people with glaucoma differ from those of people with normal vision, and to investigate the association between eye movements and impaired visual search.
Methods
Forty patients (mean age: 67 [SD: 9] years) with a range of glaucomatous visual field (VF) defects in both eyes (mean best eye mean deviation [MD]: –5.9 (SD: 5.4) dB) and 40 age-related people with normal vision (mean age: 66 [SD: 10] years) were timed as they searched for a series of target objects in computer displayed photographs of real world scenes. Eye movements were simultaneously recorded using an eye tracker. Average number of saccades per second, average saccade amplitude and average search duration across trials were recorded. These response variables were compared with measurements of VF and contrast sensitivity.
Results
The average rate of saccades made by the patient group was significantly smaller than the number made by controls during the visual search task (P = 0.02; mean reduction of 5.6% (95% CI: 0.1 to 10.4%). There was no difference in average saccade amplitude between the patients and the controls (P = 0.09). Average number of saccades was weakly correlated with aspects of visual function, with patients with worse contrast sensitivity (PR logCS; Spearman’s rho: 0.42; P = 0.006) and more severe VF defects (best eye MD; Spearman’s rho: 0.34; P = 0.037) tending to make less eye movements during the task. Average detection time in the search task was associated with the average rate of saccades in the patient group (Spearman’s rho = −0.65; P < 0.001) but this was not apparent in the controls.
Conclusions
The average rate of saccades made during visual search by this group of patients was fewer than those made by people with normal vision of a similar average age. There was wide variability in saccade rate in the patients but there was an association between an increase in this measure and better performance in the search task. Assessment of eye movements in individuals with glaucoma might provide insight into the functional deficits of the disease.
doi:10.1186/1471-2415-12-45
PMCID: PMC3505163
PMID: 22937814
Glaucoma; Eye movements; Visual search; Visual disability
Background
Economic viability of treatments for primary open-angle glaucoma (POAG) should be assessed objectively to prioritise health care interventions. This study aims to identify the methods for eliciting utility values (UVs) most sensitive to differences in visual field and visual functioning in patients with POAG. As a secondary objective, the dimensions of generic health-related and vision-related quality of life most affected by progressive vision loss will be identified.
Methods
A total of 132 POAG patients were recruited. Three sets of utility values (EuroQoL EQ-5D, Short Form SF-6D, Time Trade Off) and a measure of perceived visual functioning from the National Eye Institute Visual Function Questionnaire (VFQ-25) were elicited during face-to-face interviews. The sensitivity of UVs to differences in the binocular visual field, visual acuity and visual functioning measures was analysed using non-parametric statistical methods.
Results
Median utilities were similar across Integrated Visual Field score quartiles for EQ-5D (P = 0.08) whereas SF-6D and Time-Trade-Off UVs significantly decreased (p = 0.01 and p = 0.001, respectively). The VFQ-25 score varied across Integrated Visual Field and binocular visual acuity groups and was associated with all three UVs (P ≤ 0.001); most of its vision-specific sub-scales were associated with the vision markers. The most affected dimension was driving. A relationship with vision markers was found for the physical component of SF-36 and not for any dimension of EQ-5D.
Conclusions
The Time-Trade-Off was more sensitive than EQ-5D and SF-6D to changes in vision and visual functioning associated with glaucoma progression but could not measure quality of life changes in the mildest disease stages.
doi:10.1186/1471-2415-12-43
PMCID: PMC3552875
PMID: 22909264
Glaucoma; Quality of life; Utility values; Cost-utility analysis
Background
To evaluate the treatment with topical 0.05% cyclosporine A (CsA) in patients with subepithelial corneal infiltrates (SEI).
Methods
We reviewed 16 patients (22 eyes) before and after the treatment with 0.05% CsA eye drops. All patients had been treated previously with topical corticosteroids without any improvement and also they had to stop the medication secondary to intraocular pressure elevation. The objective data recorded included best-corrected visual acuity (BCVA), evaluation of corneal subepithelial infiltrate scores (CSIS), intraocular pressure (IOP) prior to treatment and the last follow-up visit.
Results
Six males (37.5%) and 10 females (62.5%), mean age of 35.2 ± 16.6 years, were included. The patients’ average topical CsA use duration was 5.1 ± 3.5 months (1 – 13 months). The average follow up time of the patients was 9.2 ± 4.7 months (4 – 22 months). One patient, although he didn’t have a 0 scale of SCIS, did not show up for follow up examinations after six months. The mean BCVA (logarithm of the minimum angle of resolution) before and after the treatment were 0.15 ± 0.15 and 0.07 ± 0.07 respectively, CSIS 1.68 ± 0.89 and 0.23 ± 0.53 respectively, IOP 18.50 ± 3.82 and 16.86 ± 2.76 mmHg respectively. There were statistically significant improvements in BCVA (p = 0.002), reduction of CSIS (p = 0.002) and reduction of IOP (p < 0.001) prior to treatment and the last follow-up visit. 18 eyes (81.9%) showed clinical improvement and 4 (18.1%) had decreased SEI which did not fully disappear during the treatment period. The eyes which reached CSIS score 0 (18 eyes) were treated with CsA for 1 – 13 months; while the eyes which had clinical improvement but had not CSIS score 0 (4 eyes) were decided to discontinue of CsA treatment in last follow-up visit. There were recurrences in 2 eyes 3 months after the treatment. Patients reported reduction in the severity of symptoms after the treatment. Most of the patients reported no foreign body sensation, glare, or other side effects with topical CsA treatment. Overall, patients noted an improvement in vision and satisfaction with topical 0.05% CsA treatment.
Conclusions
Topical 0.05% CsA is a safe and effective alternative treatment in patients with SEI who do not respond to other treatment modalities or have undesired side effects from topical steroids.
doi:10.1186/1471-2415-12-42
PMCID: PMC3504581
PMID: 22900547
Epidemic keratoconjunctivitis; Corneal subepithelial infiltrate; Topical 0.05% cyclosporine A
Background
Cataracts are a common and significant cause of visual impairment globally. We aimed to evaluate uncorrected distance visual acuity (UDVA) as an outcome in treating astigmatic cataract patients to assist clinicians or ophthalmologists in their decision making process regarding available interventions.
Methods
Medline, Embase and Evidence Based Reviews were systematically reviewed to identify relevant studies reporting changes in UDVA, UIVA and UNVA after cataract surgery in presbyopic patients. Strict inclusion/exclusion criteria were used to exclude any non-relevant studies. Relevant outcomes (UDVA, UIVA and UNVA) were identified from the studies retrieved through the systematic review process.
Results
The systematic review identified 11 studies which reported UCVA. All 11 studies reported UDVA. Four brands of toric intraocular lenses (IOLs) were reported in these studies. All studies identified in the literature search reported improvements in UDVA following surgical implant of a toric IOL. The largest improvements in VA were reported using the Human Optics MicroSil toric IOL (0.74 LogMAR, UDVA) and the smallest improvements were also reported using the Human Optics MicroSil toric IOL (0.23 LogMAR, UDVA) in a different study.
Conclusions
The results of this systematic review showed the aggregate of studies reporting a beneficial increase in UDVA with the use of toric IOLs in cataract patients with astigmatism.
doi:10.1186/1471-2415-12-41
PMCID: PMC3480885
PMID: 22894651
Astigmatism; Toric; Intraocular lenses; Uncorrected distance visual acuity; Uncorrected near visual acuity; Visual acuity; Systematic review; Cataracts
da Silva, Felipe T | Hirata, Carlos E | Sakata, Viviane M | Olivalves, Edilberto | Preti, Rony | Pimentel, Sergio LG | Gomes, Andre | Takahashi, Walter Y | Costa, Rogerio A | Yamamoto, Joyce H
Background
To investigate indocyanine green angiography (ICGA) findings in patients with long-standing Vogt-Koyanagi-Harada (VKH) disease and their correlation with disease activity on clinical examination as well as with systemic corticosteroid therapy.
Methods
Twenty-eight patients (51 eyes) with long-standing (≥6 months from disease onset) VKH disease whose treatment was tapered based only in clinical features were prospectively included at a single center in Brazil. All patients underwent standardized clinical evaluation, which included fundus photography, fluorescein angiography and ICGA. Clinical disease activity was determined based in the Standardization in Uveitis Nomenclature Working Group. Fisher exact test and logistic regression models were used for statistical analysis.
Results
Disease-related choroidal inflammation on ICGA was observed in 72.5% (31 of 51 eyes). Angiographic findings suggestive of (choroidal and/or retinal) disease activity were not observed on FA. Clinically active disease based on clinical evaluation was observed in 41.2% (21 of 51 eyes). In these 21 eyes, disease-related choroidal inflammation on ICGA was observed in 76.2% (16 of 21 eyes); in the remaining eyes (without clinical active disease) disease-related choroidal inflammation on ICGA was observed in 70.0% (21 of 30 eyes). In respect to systemic corticosteroid therapy, 10 patients (18 of 51 eyes) were under treatment with prednisone. In these 10 (18 of 51 eyes) patients, disease-related choroidal inflammation on ICGA was observed in 83.3% (15 of 18 eyes); in the remaining patients (33 of 51 eyes) disease-related choroidal inflammation on ICGA was observed in 66.7% (22 of 33 eyes).
Conclusion
ICGA findings suggestive of disease-related choroidal inflammation were observed in a considerable proportion of patients with long-standing VKH disease, independent of the inflammatory status of the disease on clinical examination or current use of systemic corticosteroid. Therefore, the current study reinforces the crucial role of ICGA to assist the management and treatment of patients with long-standing VKH disease.
doi:10.1186/1471-2415-12-40
PMCID: PMC3480878
PMID: 22889440
Angiography; Indocyanine green; Choroid; Diagnosis; Inflammation; Vogt-Koyanagi-Harada
Background
The influence of serous retinal detachment (SRD) on visual acuity, macular sensitivity, and macular thickness is unclear after intravitreal injection of triamcinolone acetonide (IVTA) for macular edema with branch retinal vein occlusion (BRVO).
Methods
Twenty-one eyes of 21 BRVO patients with macular edema received IVTA. Patients were divided into two groups by optical coherence tomography findings: 11 patients who had cystoid macular edema (CME) with SRD (SRD (+) group) and 10 patients who had CME without SRD (SRD (−) group). Microperimetry was performed with a Micro Perimeter 1 before and at 3 and 6 months after IVTA. Macular thickness was measured by optical coherence tomography. We exchanged the superior and inferior regions to separate the regions into those with and without occlusion. As a result, the superior region was always the occluded region and the inferior region was non-occluded.
Results
In both the SRD (−) group and the SRD (+) group, the mean macular thickness within the central 4° field and the 10° and 20° fields of the occluded region decreased significantly from baseline to 3 and 6 months after IVTA (all P <0.01). Visual acuity also improved significantly in both groups from baseline to 3 and 6 months after IVTA (both P <0.05). In both groups, the mean macular sensitivity (measured with by microperimetry) within the central 4° field and the 10° and 20° fields of the occluded region showed a significant increase from baseline to 3 and 6 months after IVTA (all P <0.05). The trend profiles of macular thickness within the 10° and 20° fields of the occluded region showed significant differences, but there were no significant differences with respect to the trend profiles of visual acuity and macular sensitivity within the central 4° field and the 10° and 20° fields of the occluded region.
Conclusions
These results suggest that IVTA may achieve more marked improvement of macular morphology in BRVO patients with SRD than in those without SRD, while this therapy may have a similar effect on macular function in BRVO patients with or without SRD.
doi:10.1186/1471-2415-12-39
PMCID: PMC3532084
PMID: 22876931
Background
To evaluate the safety of pegaptanib sodium 0.3 mg intravitreal injection in the treatment of neovascular age-related macular degeneration in subjects with or without diabetes mellitus.
Methods
A pooled, retrospective, analysis was conducted of data from 9 sponsor-administered, randomized, open-label trials. Subjects who received pegaptanib by randomization or change in dose assignment, crossover design, or protocol amendment, were included. Reports of endophthalmitis, increased intraocular pressure, retinal injury, intraocular hemorrhage, traumatic cataract, hypersensitivity reactions, stroke, myocardial infarction, and other arterial thromboembolic events defined by the Antiplatelet Trialists’ Collaboration were identified by Medical Dictionary for Regulatory Activities preferred terms. Adverse events were summarized from the first injection to 42 days after the last injection. The incidence of adverse events was stratified by the presence/absence of diabetes.
Results
Of 1,586 subjects enrolled, 165 (10.4%) had a history of diabetes mellitus and 1,421 (89.6%) did not. The 2 populations were similar at baseline. Based on the comparison of prespecified ocular, hypersensitivity, and Antiplatelet Trialists’ Collaboration event terms, the safety review did not identify any notable differences between the 2 populations.
Conclusions
This retrospective analysis found no increased safety risk resulting from treatment with pegaptanib 0.3 mg in individuals with neovascular age-related macular degeneration and concomitant diabetes mellitus.
doi:10.1186/1471-2415-12-37
PMCID: PMC3472216
PMID: 22871086
Background
To identify preoperative, perioperative and postoperative risk factors that influence the success of pterygium surgery.
Methods
This is a prospective study of thirty-six patients with primary or recurrent pterygia. A detailed anamnesis and an ophthalmological examination were performed looking for the following factors: age, race, latitude and altitude of the main place of residence, hours of exposure to the sun, use of protective measures against UV-radiation, classification of pterygium, width of the pterygium at limbus, surgical technique (conjunctival autograft plus suturing versus tissue glue), graft alterations (misapposition, granuloma, haemorrhage, oedema, retraction or necrosis), and postoperative symptoms (foreign-body sensation, pain). The examinations were performed 2 and 7 days and 2, 6 and 12 months after surgery. In addition, recurrence was defined as any growth of conjunctiva into the cornea.
Results
A logistic regression and a survival analysis have been used to perform data analysis. A total number of 36 patients completed a one year follow-up. A total of 13 patients were born and lived in Spain, and 26 came from other countries, mostly Latin America. A total number of 8 males (no women) presented a recurrence, mainly between 2 and 6 months. The hours of sun exposure through their life was independently related to surgical success. Pterygia of less than 5 mm of base width showed a weak positive correlation with recurrence. None of the other factors considered were significantly related to recurrence.
Conclusions
Male gender and high sun exposure are strongly and independently related to surgical success after the removal of pterygia.
doi:10.1186/1471-2415-12-38
PMCID: PMC3497872
PMID: 22873737
Risk factors; Sunlight exposure; Pterygium surgery; Conjunctival autograft
Background
The purpose of this study is to validate the use of visual evoked potential (VEP) to objectively quantify visual acuity in normal and amblyopic patients, and determine if it is possible to predict visual acuity in disability assessment to register visual pathway lesions.
Methods
A retrospective chart review was conducted of patients diagnosed with normal vision, unilateral amblyopia, optic neuritis, and visual disability who visited the university medical center for registration from March 2007 to October 2009. The study included 20 normal subjects (20 right eyes: 10 females, 10 males, ages 9–42 years), 18 unilateral amblyopic patients (18 amblyopic eyes, ages 19–36 years), 19 optic neuritis patients (19 eyes: ages 9–71 years), and 10 patients with visual disability having visual pathway lesions. Amplitude and latencies were analyzed and correlations with visual acuity (logMAR) were derived from 20 normal and 18 amblyopic subjects. Correlation of VEP amplitude and visual acuity (logMAR) of 19 optic neuritis patients confirmed relationships between visual acuity and amplitude. We calculated the objective visual acuity (logMAR) of 16 eyes from 10 patients to diagnose the presence or absence of visual disability using relations derived from 20 normal and 18 amblyopic eyes.
Results
Linear regression analyses between amplitude of pattern visual evoked potentials and visual acuity (logMAR) of 38 eyes from normal (right eyes) and amblyopic (amblyopic eyes) subjects were significant [y = −0.072x + 1.22, x: VEP amplitude, y: visual acuity (logMAR)]. There were no significant differences between visual acuity prediction values, which substituted amplitude values of 19 eyes with optic neuritis into function. We calculated the objective visual acuity of 16 eyes of 10 patients to diagnose the presence or absence of visual disability using relations of y = −0.072x + 1.22 (−0.072). This resulted in a prediction reference of visual acuity associated with malingering vs. real disability in a range >5.77 μV. The results could be useful, especially in cases of no obvious pale disc with trauma.
Conclusions
Visual acuity quantification using absolute value of amplitude in pattern visual evoked potentials was useful in confirming subjective visual acuity for cutoff values >5.77 μV in disability evaluation to discriminate the malingering from real disability.
doi:10.1186/1471-2415-12-36
PMCID: PMC3439363
PMID: 22866948
Pattern visual evoked potentials (VEP); Disability assessment; Objective visual acuity; Malingering
Background
The purpose of this study was to compare the monocular Humphrey Visual Field (HVF) with the binocular Humphrey Esterman Visual Field (HEVF) for determining whether subjects suffering from glaucoma fulfilled the new medical requirements for possession of a Swedish driver’s license.
Methods
HVF SITA Fast 24–2 full threshold (monocularly) and HEVF (binocularly) were performed consecutively on the same day on 40 subjects with glaucomatous damage of varying degrees in both eyes. Assessment of results was constituted as either “pass” or “fail”, according to the new medical requirements put into effect September 1, 2010 by the Swedish Transport Agency.
Results
Forty subjects were recruited and participated in the study. Sixteen subjects passed both tests, and sixteen subjects failed both tests. Eight subjects passed the HEFV but failed the HVF. There was a significant difference between HEVF and HVF (χ2, p = 0.004). There were no subjects who passed the HVF, but failed the HEVF.
Conclusions
The monocular visual field test (HVF) gave more specific information about the location and depth of the defects, and therefore is the overwhelming method of choice for use in diagnostics. The binocular visual field test (HEVF) seems not be as efficient as the HVF in finding visual field defects in glaucoma subjects, and is therefore doubtful in evaluating visual capabilities in traffic situations.
doi:10.1186/1471-2415-12-35
PMCID: PMC3479058
PMID: 22856469
Visual fields; Glaucoma; Driving fitness
Bakground
To evaluate objectively the anatomical and functional changes of optic nerve in eyes with primary open angle glaucoma (POAG) by the joint use of optical coherence tomography (OCT) and multifocal visual evoked potentials (mfVEP).
Methods
29 eyes with open angle glaucoma and visual field defects, as well as 20 eyes of 10 age-matched control normal subjects were tested. All participants underwent a complete ophthalmological examination. Moreover, Humphrey visual field test, OCT examination and recording of mfVEP were performed. Amplitude and implicit time of mfVEP, as well as RNFL thickness were measured. Differences in density components of mfVEP and in RNFL thickness among POAG eyes and control eyes were examined using Student’s t-test.
Results
In glaucomatous eyes the mean Retinal Response Density (RRD) was lower than normal in ring 1, 2 and 3 of mfVEP (p < 0.0001). Specifically the mean amplitude of mfVEP in POAG eyes was estimated at 34.2 ± 17.6 nV/deg2, 6.9 ± 4.8 nV/deg2 and 2.6 ± 1.6 nV/deg2 in rings 1, 2 and 3 respectively. In contrast the mean implicit time was similar to control eyes. In addition, the mean RNFL thickness in POAG eyes was estimated at 76.8 ± 26.6 μm in the superior area, 52.1 ± 16.3 μm in the temporal area, 75.9 ± 32.5 μm in the inferior area and 58.6 ± 19.4 μm in the nasal area. There was a statistically significant difference in RNFL thickness in all peripapillary areas (p < 0.0001) between POAG eyes and controls, with superior and inferior area to present the highest decrease.
Conclusions
Our study shows that, although Standard Automatic Perimetry is the gold standard to evaluate glaucomatous neuropathy, the joint use of mfVEP and OCT could be useful in better monitoring glaucoma progression.
doi:10.1186/1471-2415-12-34
PMCID: PMC3549724
PMID: 22856337
Background
Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) allows selective replacement of the endothelium. Post-operative haze and particles can affect the interface quality and, ultimately, visual outcome. In this study, we evaluated DSAEK interface with in vivo laser confocal microscopy (LCM) in order to: (i) correlate interface status with best corrected visual acuity, and (ii) with time from surgery; (iii) correlate interface particle number with best corrected visual acuity. Host-donor interface was imaged and graded using a published reflectivity scale. Particles at the interface were counted.
Methods
18 eyes of 16 patients (6 males and 10 females); mean age: 74 ± 8.3 years which underwent DSAEK were examined by means of in vivo laser confocal microscopy between 1 and 24 months after surgery. Host-donor interface was imaged and graded using a published reflectivity scale. Particles present at the interface were counted.
Results
Interface reflectivity was 2.17 ± 1.2 and significantly correlated with visual acuity (Spearman correlation coefficient −0.83; P < 0.001), and with time after surgery (Spearman correlation coefficient −0.87; P < 0.001). Visual acuity was 0.67 ± 0.27. The number of particles was 205 ± 117.8; no correlation was found between this number and visual acuity (Spearman correlation coefficient −0.41; P = 0.15).
Conclusion
DSAEK interface imaged with LCM is helpful in diagnosing poor host-donor interface quality in DSAEK surgery. A good quality interface is related to a better visual acuity. Moreover, the quality of the interface appears to improve as time passes from the surgery. Interface quality is related with visual acuity and improves with time from surgery. LCM should be considered as an added tool in post-DSAEK follow-up of patients. Finally, our study shows that the presence of particles does not influence visual outcome.
doi:10.1186/1471-2415-12-32
PMCID: PMC3441224
PMID: 22853313
DSAEK; Interface; Laser corneal confocal microscopy
Background
To assess which of three methods, namely, optical coherence tomography (OCT), pattern electroretinogram (PERG) or frequency-doubling technology (FDT), is the most sensitive and specific for detecting early glaucomatous damage in ocular hypertension (OH).
Methods
Fifty-two patients with OH (24 men and 28 women, mean age of 56 ± 9.6 years) with an intraocular pressure (IOP) > 21 mmHg and fifty-two control patients (25 men and 27 women, mean age of 54.8 ± 10.4 years) with IOP < 21 mmHg, were assessed. All the patients had normal visual acuity, normal optic disk and normal perimetric indices.
All subjects underwent OCT, FDT and PERG. Data were analyzed with unpaired t-tests, Chi-square test and Receiver Operating Characteristic (ROC) curve analyses.
Results
In patients with OH, OCT showed retinal nerve fiber layer (RNFL) thinner than in control group in the superior quadrant (130.16 ± 10.02 vs 135.18 ± 9.27 μm, respectively; p < 0.011) and inferior quadrant (120.14 ± 11.0 vs 132.68 ± 8.03 μm; p < 0.001). FDT showed a significantly higher pattern standard deviation (PSD) (3.46 ± 1.48 vs 1.89 ± 0.7 dB; p < 0.001). With respect to PERG, only the amplitude showed significant differences (p < 0.044) between the two groups. ROC curve analysis revealed a sensitivity and specificity of 92% and 86%, respectively, for FDT-PSD (with an area under the ROC curve of 0.940), whereas with OCT, a sensitivity of 82% and a specificity of 74% was recorded in the inferior RNFL quadrant (with an area under the ROC curve of 0.806) finally with PERG amplitude we found a sensitivity of 52% and specificity of 77% (with an area under the ROC curve of 0.595).
Conclusions
FDT is the most sensitive and specific method for detecting early glaucomatous damage in eyes with OH, and together with OCT, can be useful in identifying those patients who may develop glaucoma.
Trial registration
ISRCT number: ISRCTN70295497
doi:10.1186/1471-2415-12-33
PMCID: PMC3444883
PMID: 22853436
Frequency-doubling technology; Ocular hypertension; Optical coherence tomography; Pattern electroretinogram; Retinal ganglion cells; Retinal nerve fiber layer
Background
Low vision is an important public health problem; however, very few low vision clinics are available to address the needs of low vision patients in most developing countries. The purpose of this study was to describe the characteristics of patients attending the low vision clinic of a Nigerian tertiary hospital.
Methods
This was a prospective cross sectional study of all new patients seen at the low vision clinic over a 36 month period. Patients were administered with a structured questionnaire, and were examined and tested with low vision devices by the attending low vision specialist. Information on the demographic and clinical characteristics of the patients was recorded.
Results
A total of 193 new patients seen during the period were studied. The mean age was 41.4 years, and their ages ranged between 6 and 90 years with a male to female ratio of 1.9:1. Majority (58%) were aged below 50 years, 23.3% were children (≤15 years), while 21.8% were elderly patients (≥65 years). The commonest cause of low vision was retinitis pigmentosa (16.6%); 14.5% had age related macular degeneration (ARMD); 9.8% had albinism; while only 1% had diabetic retinopathy. ARMD (45.2%) was the commonest cause in the elderly patients, while albinism (24.4%) and optic atrophy (24.4%) were the commonest in children.
Conclusion
The demographic and clinical characteristics of low vision patients seen in this clinic are similar to that of patients in other developing countries, but different from those in developed countries. Elderly patients and females may be under-utilising low vision services. There is a need for further research into the determinants of low vision service utilisation in developing countries. This would further aid the planning and delivery of services to low vision patients in these countries.
doi:10.1186/1471-2415-12-31
PMCID: PMC3466151
PMID: 22846399
Low vision; Patient characteristics; Developing countries
Background
Macular thickening (MT) without clinically recognized macular edema has been described in anterior uveitis (AU). Although fellow-eyes of patients have been used as controls in several studies, little is known about macular thickness in these eyes. We studied the rate and extent of MT in both AU-affected and quiescent fellow-eyes of phakic AU patients with good visual acuity (VA). We also assessed macular thickness related to HLA-B27 presence and to recurrence, since these issues have been almost unexplored by previous optical coherence tomography (OCT) studies.
Methods
Patients with AU were prospectively included and macular thickness was measured with OCT initially and on follow up. Macular thickness in patients’ affected eyes (n = 30) as well as in their quiet fellow-eyes (n = 28) was compared with eyes of age- and gender matched controls. Inter-ocular differences in macular thickness between AU affected eyes and their fellow-eyes were assessed in patients (n = 28), also in a subgroup with visual acuity ≥ 0.8 (n = 23) by one-sample Student’s t-tests. Inter-ocular differences were also assessed related to HLA-B27 presence and related to the status of current AU episode (initial or relapse).
Results
Subclinical MT is present in both quiet fellow-eyes and AU-affected eyes of patients. MT was found in most cases of AU, even in phakic eyes with good VA. There was a larger increase in macular thickness in HLA-B27-positive than in HLA-B27-negative patients. No differences in macular thickness were found between patients with their first AU episode and patients with recurrent episodes.
Conclusions
MT probably reflects systemic immune-mediated response to the inflammatory disorder in AU, and it is possible that HLA-B27-related factors are involved in the pathogenesis of AU. These observations are in line with and extend the current understanding of the mechanisms behind MT in AU.
doi:10.1186/1471-2415-12-30
PMCID: PMC3479004
PMID: 22839430
Background
Carotid cavernous fistulas are abnormal communications between the cavernous sinus and the external or internal carotid arteries. Although rare, closure of carotid cavernous fistulas can lead to immediate ocular complications. To our knowledge, our case represents the first report of worsening angle closure glaucoma and choroidal detachments over an extended period of two months subsequent to closure of a carotid cavernous fistula.
Case presentation
A 70-year-old female with a history of primary angle closure glaucoma presented with 4 mm of proptosis, resistance to retropulsion, tortuous corkscrew blood vessels and an orbital bruit of the right eye. Diagnostic cerebral angiogram showed a small indirect Barrow type D right carotid cavernous fistula. Transarterial embolization was planned but repeat cerebral angiography prior to the procedure demonstrated spontaneous partial closure of the carotid cavernous fistula and the procedure was aborted. One month later, our patient was noted to have worsening vision and choroidal detachments of the right eye. She declined further testing and was thus started on self-administered manual carotid jugular compressions. One month later, she developed progressive worsening of her choroidal detachments and angle closure. She eventually opted for surgical intervention but repeat cerebral angiography showed significant thrombosis of the carotid cavernous fistula and no intervention was warranted. Examination two months later showed complete resolution of the choroidal detachments and open angles of both eyes.
Conclusions
Our patient demonstrated worsening angle closure glaucoma and choroidal detachments after spontaneous closure of her carotid cavernous fistula had been noted. Ocular complications, including acute angle closure, have been reported to occur immediately after closure of carotid cavernous fistulas, but not over months as in our patient. It is imperative that individuals who have undergone apparent closure of a carotid cavernous fistula be carefully monitored for worsening ocular complications.
doi:10.1186/1471-2415-12-28
PMCID: PMC3412712
PMID: 22839357
Background
To compare peripapillary choroidal thickness measurements between normal and normal-tension glaucoma eyes.
Methods
Cross-sectional comparative study. 50 normal and 52 normal-tension glaucoma subjects were enrolled in the study. Peripapillary choroidal thickness was measured with spectral-domain optical coherence tomography and enhanced depth imaging. After obtaining circular B-scans around the disc, choroidal thicknesses were calculated based on the exported segmentation values. Visual fields were measured using automated perimetry. Difference in peripapillary choroidal thickness between the normal subjects and the patients with normal-tension glaucoma was analyzed.
Results
There were no significant differences in age, axial length, or refraction between the two groups. Peripapillary choroidal thickness was inversely correlated with age in both the normal (r = −0.287, P = 0.04) and normal and normal-tension glaucoma (r = −0.322, P = 0.02) groups. Peripapillary choroidal thickness of inferonasal (125 vs 148 μm, P < 0.05), inferior (101 vs 122 μm, P < 0.05), or inferotemporal (100 vs 127 μm, P < 0.05) regions were significantly thinner in the normal-tension glaucoma group as compared to normal subjects. Superior visual hemifield defect was significantly worse than inferior visual hemifield defect in normal and normal-tension glaucoma patients.
Conclusion
As compared to normal subjects, peripapillary choroidal thickness was significantly thinner in the normal and normal-tension glaucoma patients, at least in some locations.
doi:10.1186/1471-2415-12-29
PMCID: PMC3479055
PMID: 22839368
Peripapillary choroidal thickness; Enhanced depth imaging optical coherence tomography; Normal-tension glaucoma
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 1.5–3× as large as that seen in adults NV. The magnitude of contour interaction normally ranges between 1–2 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.
doi:10.1186/1471-2415-12-27
PMCID: PMC3416571
PMID: 22824242
Background
Dust exposure is a well-known occupational hazard for terrestrial workers and astronauts alike and will continue to be a concern as humankind pursues exploration and habitation of objects beyond Earth. Humankind’s limited exploration experience with the Apollo Program indicates that exposure to dust will be unavoidable. Therefore, NASA must assess potential toxicity and recommend appropriate mitigation measures to ensure that explorers are adequately protected. Visual acuity is critical during exploration activities and operations aboard spacecraft. Therefore, the present research was performed to ascertain the ocular toxicity of authentic lunar dust.
Methods
Small (mean particle diameter = 2.9 ± 1.0 μm), reactive lunar dust particles were produced by grinding bulk dust under ultrapure nitrogen conditions. Chemical reactivity and cytotoxicity testing were performed using the commercially available EpiOcularTM assay. Subsequent in vivo Draize testing utilized a larger size fraction of unground lunar dust that is more relevant to ocular exposures (particles <120 μm; median particle diameter = 50.9 ± 19.8 μm).
Results
In vitro testing indicated minimal irritancy potential based on the time required to reduce cell viability by 50% (ET50). Follow-up testing using the Draize standard protocol confirmed that the lunar dust was minimally irritating. Minor irritation of the upper eyelids was noted at the 1-hour observation point, but these effects resolved within 24 hours. In addition, no corneal scratching was observed using fluorescein stain.
Conclusions
Low-titanium mare lunar dust is minimally irritating to the eyes and is considered a nuisance dust for ocular exposure. No special precautions are recommended to protect against ocular exposures, but fully shielded goggles may be used if dust becomes a nuisance.
doi:10.1186/1471-2415-12-26
PMCID: PMC3484112
PMID: 22817808
Background
To report two cases of atypical vitelliform macular dystrophy misdiagnosed as chronic central serous chorioretinopathy.
Case presentation
Two patients with incidentally discovered abnormalities of the retina without specific symptoms were referred to our hospital for consultation. Bilateral macula atrophic lesions were observed and optical coherence tomography revealed serous retinal detachment in the macula. Fluorescein angiography showed multiple leakages around the central hypofluorescent area and indocyanine green angiography showed partially dilated choroidal vessels. Fundus autofluorescence (FAF) showed a decreasing pattern of autofluorescence in the subretinal fluid area, and increasing autofluorescence at the border of the serous retinal detachment. Both patients were diagnosed with chronic central serous chorioretinopathy. Photodynamic therapy and intravitreal bevacizumab injection were administered for engorged choroidal vessels during follow-up, but neither patient showed improvement in symptoms or ophthalmologic findings. Based on re-evaluation by fundus photography, optical coherence tomography, fluorescein angiography, and comparison of the results of FAF with the first visit, vitelliform macular dystrophy was suspected and a definite diagnosis was made by electrooculography and genetic testing.
Conclusion
In patients with continuous serous retinal detachment without response to photodynamic therapy or intravitreal bevacizumab injection, careful fundus exam and FAF can be used to diagnose atypical vitelliform macular dystrophy.
doi:10.1186/1471-2415-12-25
PMCID: PMC3549736
PMID: 22817759
Background
To determine the agreement between intraocular pressure and the ‘Wuerzburg bleb classification score’, as well as between single items of the score and intraocular pressure. Interobserver variability was analyzed.
Methods
57 post-trabeculectomy eyes were included. Colour photographs were used to score the filtering bleb in accordance to the Wuerzburg bleb classification score by two different examiners. At the same visit, clinical data such as intraocular pressure, best corrected visual acuity, slit lamp biomicroscopy and medical history were obtained by another examiner.
Results
After trabeculectomy, 42 out of 57 eyes (73.7%) reached the target pressure (≤21mmHg, and intraocular pressure reduction of at least 20%, without antiglaucoma medication, and without any additional intervention). Fair agreement was found between intraocular pressure and Wuerzburg bleb classification score ≥8 points and ≥7 points (kappa 0.24 and 0.27, respectively). Analyzing the subgroups of the morphological criteria, best agreement was found between occurrence of microcysts and target intraocular pressure (к 0.22 – 0.34).
Conclusions
Evaluating filtering blebs after trabeculectomy by using the Wuerzburg bleb classification score is a good technique for predicting intraocular pressure control in eyes attaining a minimum score of seven points. The presence of microcysts on the filtering bleb predicts that the eye is likely to attain target pressure.
doi:10.1186/1471-2415-12-24
PMCID: PMC3439283
PMID: 22805056
Filtering bleb; Glaucoma; Filtration surgery; Bleb grading; Trabeculectomy
Background
To establish clinical expectations when using the Lenstar LS 900® dual-zone automated keratometer for surgery planning of toric intraocular lenses.
Methods
Fifty eyes were measured with the Lenstar LS 900® dual-zone automated keratometer . Surgical planning was performed with the data from this device and the known surgically induced astigmatism of the surgeon. Post-operative refractions and visual acuity were measured at 1 month and 3 months.
Results
Clinical outcomes from 43 uncomplicated surgeries showed an average post-operative refractive astigmatism of 0.44D ±0.25D. Over 70% of eyes had 0.50D or less of refractive astigmatism and no eye had more than 1.0D of refractive astigmatism. Uncorrected visual acuity was 20/32 or better in all eyes at 3 months, with 70% of eyes 20/20 or better. A significantly higher number of eyes had 0.75D or more of post-operative refractive astigmatism when the standard deviation of the pre-operative calculated corneal astigmatism angle, reported by the keratometer, was > 5 degrees.
Conclusions
In this single-site study investigating the use of the keratometry from the Lenstar LS 900® for toric IOL surgical planning, clinical outcomes appear equivalent to those reported in the literature for manual keratometry and somewhat better than has been reported for some previous automated instruments. A high standard deviation in the pre-operative calculated astigmatism angle, as reported by the keratometer, appears to increase the likelihood of higher post-operative refractive astigmatism.
doi:10.1186/1471-2415-12-21
PMCID: PMC3409075
PMID: 22800184
Toric IOL; Astigmatism; Cataract surgery; Cataract surgery planning; Keratometer; Lenstar LS 900®
Background
To determine the efficacy of high-dose antioxidants in the acute stage of central serous chorioretinopathy (CSC).
Methods
This was a randomized placebo-controlled study. The patients with acute CSC (onset within 6 weeks) were randomized to receive either high-dose antioxidant tablets (study group A) or placebo tablets (control group B) for 3 months or until the complete resolution of subretinal fluid. After 3 months, additional treatment with laser or photodynamic therapy (PDT) was considered if any fluorescein leakage persisted. The outcomes measured were the changes in visual acuity (VA) and central macular thickness (CMT), the number of patients with subretinal fluid at each follow-up time, the number of patients with fluorescein leakage at the end of the 3rd month and patients who received additional treatments.
Results
Fifty-one of 58 patients (88%) completed the follow-up criteria. The baseline demographic data were comparable in both groups. At the end of the 3rd month, the VA and CMT showed no statistical difference between the groups but the patients in group A has less fluorescein leakage and additional treatments than in group B (p = 0.027 and 0.03).
Conclusion
The high-dose antioxidants for acute CSC did not show any benefits in VA and CMT. However, the drugs might decrease the chance for fluorescein leakage and additional treatments at the end of the 3rd month.
doi:10.1186/1471-2415-12-20
PMCID: PMC3410804
PMID: 22800086
Antioxidants; Central serous chorioretinopathy