Journal of Ophthalmic and Vision Research
Volume:10 Issue: 2, Apr-Jun 2015

To determine the prevalence of various types of conjunctival lesions, at a tertiary ophthalmic center in Fars Province, South of Iran. Histopathologic slides and medical records of conjunctival lesions submitted to the pathology department of Khalili Hospital, Shiraz, Iran were reviewed from April, 2009 to July, 2013. The histopathologic diagnoses were categorized into benign, pre-malignant, and malignant lesions. The prevalence of various types of conjunctival lesions was calculated. Histologic sections of 631 conjunctival lesions were reviewed. Benign lesions were most prevalent (81.8%), followed by premalignant (10.8%) and malignant (7.4%) lesions. Pterygia were the most common benign lesions (69.2%), intraepithelial dysplasia constituted most cases of premalignant lesions (94.1%), and squamous cell carcinoma was the most frequent malignant lesion (93.6%). Benign lesions were the most common type of lesions in all age groups, however the prevalence of malignant lesions increased significantly with age (P < 0.001). Benign lesions were the most common conjunctival lesions with pterygia on top of the list, while intraepithelial neoplasia and squamous cell carcinoma were the most common premalignant and malignant lesions, respectively. Conjunctival malignant lesions were more prevalent with older age.

To determine whether corneal sensitivity is different between the two genders. Corneal sensitivity of 130 normal volunteers, including 77 women and 53 men aged 20-35 years, with no history of previous ocular surgery was measured using the Cochet-Bonnet esthesiometer. Measurements were done on five corneal regions: central, nasal, inferior, temporal and superior. The findings were compared between men and women using the non-parametric Mann-Whitney U test. Mean age of male subjects was 28.0 years and that of female participants was 26.8 years (P = 0.063). There was a significant difference in corneal sensitivity between men and women in the superior (P = 0.013), temporal (P = 0.020) and inferior (P = 0.046) regions. There was no significant difference in corneal sensitivity in the central (P = 0.862) and nasal (P = 0.273) regions. Except for the central and nasal regions, corneal sensitivity is significantly higher in men as compared to women. The reason for this difference is not yet evident.

To assess the efficacy of chlorhexidine monotherapy for Acanthamoeba keratitis, and to determine the therapeutic outcomes of concomitant topical corticosteroids. In this prospective interventional case series, 31 eyes of 31 patients with Acanthamoeba keratitis (AK) were treated with chlorhexidine 0.02% as monotherapy, from April 2010 to April 2011. The diagnosis of AK was made based on clinical manifestations and positive confocal microscopic (confoscan 3.4, Nidek Co. Ltd., Gamagori, Japan) results. We report the percentage of a favorable clinical response within two weeks of initiating treatment, worsening of the infection while receiving chlorhexidine, recovery of visual acuity (VA), duration of treatment with chlorhexidine and corticosteroids, necessity for addition of other anti-Acanthamoeba agents, presence of corneal scar at the end of the treatment, and need for penetrating keratoplasty (PK). Two weeks after initiation of chlorhexidine, improvement in signs and symptoms was observed in 26 (83.9%) patients but 3 eyes required the addition of propamidine. After initial improvement in one patient, the infection worsened, necessitating the addition of Polyhexamethylene Biguanide (PHMB) and propamidine. A total of 26 (83.9%) patients received topical corticosteroids with mean duration of 65.8 ± 45.1 days. In 22 (71%) eyes, final visual acuity was≥0.80. Improved VA occurred in 29 eyes (93.5%). Optical PK was considered in 3 (9.7%) eyes and a corneal scar developed in 8 (25.8%) eyes. Chlorhexidine is effective for monotherapy in AK and could be a good choice for initiating treatment. After the initial response to anti-Acanthamoeba agents, corticosteroids can be used as adjunctive therapy depending on the clinical condition.

To compare the clinical outcomes of deep anterior lamellar keratoplasty (DALK) for keratoconus in patients with vernal keratoconjunctivitis (VKC) versus those without VKC. In this retrospective comparative study, records of 262 eyes with keratoconus (Group 1) and 28 keratoconic eyes with VKC (Group 2) that had undergone DALK were compiled. Reviewed parameters included length of follow-up, best-corrected visual acuity (BCVA), refractive error, complications and cumulative graft survival. Mean duration of follow-up was 38.6 ± 20.2 and 34.4 ± 20.9 months in groups 1 and 2, respectively (P= 0.21). Mean post-operative BCVA was 0.19 ± 0.11 and 0.20 ± 0.15 logMAR, in groups 1 and 2 (P= 0.79). BCVA≥20/40 was achieved in 91.6 and 88.5% of eyes in groups 1 and 2, respectively (P = 0.48). Epithelial problems were encountered in 31.3 and 42.9% of operated eyes, respectively (P= 0.16). Vascularization of suture tracts and stitch abscesses were encountered more frequently in the eyes with VKC (P= 0.01 and <0.001, respectively). At the 33-month follow-up examination, rejection-free graft survival rates were 56.0% in group 1 and 33.3% in group 2, with mean durations of 41.0 and 32.1 months, respectively (P= 0.15). Graft survival rates were 98.1% in group 1 and 95.0% in group 2, with mean durations of 88.6 and 88.4 months, respectively (P= 0.74). Clinical outcomes of DALK in keratoconic eyes with VKC were comparable to those in eyes with keratoconus alone. However, complications such as suture tract vascularization and stitch abscesses were more common when VKC coexisted, necessitating closer monitoring.

To evaluate changes in crystalline lens densitometry following corneal cross-linking (CXL) in keratoconic patients. In a quasi-experimental study, three-dimensional lens densitometry was performed using the Pentacam Scheimpflug camera (Oculus Optikgerate GmbH, Wetzlar, Germany) at baseline and six months after CXL. Densitometry was performed in a fixed area of 2 inch × 1 inch of the anterior capsule and anterior lens cortex. The subject group included patients with progressive keratoconus who underwent CXL (n = 40) and the control group was comprised of aged-matched patients with non-progressive keratoconus (n = 36). Mean age of the case and control groups was 25.8 ± 4.0 and 25.0 ± 4.1 years, respectively (P = 0.392). Mean lens density in the CXL group was 6.68% ± 0.58% at baseline and 6.77% ± 0.53% at the last visit (P = 0.352). Corresponding figures in the control group were 6.53% ± 0.27% and 6.39% ± 0.31%, respectively (P = 0.213). There was no significant difference between the study groups at baseline or six months later (P = 0.96). In this short term study with six month's follow-up, we observed no significant impact on lens density following exposure of the crystalline lens to ultraviolet A and riboflavin free radicals in the CXL procedure.

To assess the association of LTBP2 mutations with primary angle closure glaucoma (PACG). We studied 54 unrelated patients with PACG and one individual with pseudoexfoliation accompanied with angle closure glaucoma; these consisted of 28 female and 27 male subjects aged 27 to 82 (mean, 63) years. The 36 exons and flanking intronic sequences of LTBP2 in all patients were amplified by PCR and sequenced by the Sanger protocol. The sequences were compared to LTBP2 reference sequences. A total of 100 to 400 controls aged at least 60 years old were screened for various variations. Out of 24 observed sequence variations, ten were in amino acid coding regions; of these four created synonymous codons while six caused amino acid changes. Based on allele frequencies, biochemical parameters, absence in control individuals, evolutionary conservation of affected amino acids, and bioinformatic predictions on the effects on protein function, it was concluded that only two mutations causing p. Gln1417Arg and p. Gly1660Trp may contribute to PACG. The p. Gly1660Trp mutation was observed in a patient with both PACG and PEX syndrome. P. Gln1417Arg had previously been reported only in a subject with POAG. LTBP2 may contribute to PACG. This finding emphasizes that there may be an overlap in the etiology of various forms of glaucoma and the overlaps likely contribute to common features in various forms of glaucoma.

To determine the prevalence of color vision deficiency (CVD) and its correlation with amblyopia and refractive errors among primary school children. In this population-based cross-sectional study, 2160 children were selected from 36 primary schools; 60 students were from each school (10 students in each grade), with equal sex distribution. A complete eye examination including refraction using a photorefractometer, determination of visual acuity (VA) and color vision using a Yang vision tester, and evaluation of ocular media opacity using a direct ophthalmoscope was performed. Children who could not answer at least 4 plates of the Ishihara color test were considered as color vision deficient subjects. Amblyopia was determined if pinhole VA was worse than 0.3 LogMAR (equal to 20/40). The prevalence of CVD was 2.2% (95% CI: 1.5% to 3%) which was higher in male subjects (37 [3.5%] boys vs. 11 [1.0%] girls, P < 0.001). Mean VA was lower among students with CVD as compared to normal color vision children (P = 0.035) and amblyopia was observed in 8.3% (95% CI: 0.2% to 16.4%) of patients with CVD versus 2.1% (95% CI: 1.5% to 2.08%) of children with normal color vision perception (P = 0.005). A statistically significant correlation between lower VA and CVD was observed (P = 0.023). Although CVD was correlated with lower VA and amblyopia, there was no relationship between CVD and the type of amblyopia, refractive error, anisometropia or strabismus.

To determine the etiology, clinical features and outcomes of bilateral vitreous hemorrhage (VH) in children. This retrospective chart review was performed on patients with bilateral VH under the age of 18 at a tertiary eye care center in India. Data included demographics, details of history and ocular examination, reports of investigations, surgeries or other interventions performed, and final anatomical and visual outcomes. Patients were divided into two groups i.e., traumatic and non-traumatic (spontaneous). The traumatic group was comprised of 37 patients including 27 male and 10 female subjects with mean age of 13.47 ± 5.31 years, the most common complaint was decreased vision (96.45%) and the most prevalent etiology was firecracker injury in 16 (43.2%) patients. Mean baseline visual acuity (VA) was 2.34 ± 1.31 logMAR which was significantly improved to 1.08 ± 0.23 logMAR (P = 0.042). The mean number of surgeries was 2.72 ± 1.43 in the traumatic VH and mean follow up period was 23.14 ± 6.54 months. The spontaneous group included 48 subjects comprised of 27 male and 21 female cases with mean age of 14.48 ± 2.03 years. The most common cause was vasculitis in 21 (43.75%) subjects including four patients with tuberculosis. Mean baseline VA was 1.97 ± 1.13 logMAR which showed a significant improvement to 0.82 ± 0.24 logMAR (P = 0.012) after mean follow up of 34.2 ± 11.2 months. Eleven patients required at least one major surgery. Vasculitis was the most common cause of spontaneous bilateral VH; traumatic VH most prevalently occurred due to firecracker injury. Final VA was better in the spontaneous group.

To describe the effect of monocular deprivation on densities of neural retinal cells in rabbits. Thirty rabbits, comprised of 18 subject and 12 control animals, were included and monocular deprivation was achieved through unilateral lid suturing in all subject animals. The rabbits were observed for three weeks. At the end of each week, 6 experimental and 3 control animals were euthanized, their retinas was harvested and processed for light microscopy. Photomicrographs of the retina were taken and imported into FIJI software for analysis. Neural retinal cell densities of deprived eyes were reduced along with increasing period of deprivation. The percentage of reductions were 60.9% (P < 0.001), 41.6% (P = 0.003), and 18.9% (P = 0.326) for ganglion, inner nuclear, and outer nuclear cells, respectively. In non-deprived eyes, cell densities in contrast were increased by 116% (P < 0.001), 52% (P < 0.001) and 59.6% (P < 0.001) in ganglion, inner nuclear, and outer nuclear cells, respectively. In this rabbit model, monocular deprivation resulted in activity-dependent changes in cell densities of the neural retina in favour of the non-deprived eye along with reduced cell densities in the deprived eye.

To evaluate plasma levels of endothelin-1 (ET-1) and nitric oxide (NO) in patients with exudative age-related macular degeneration (AMD). In this study, ET-1 levels, as well as nitrite plus nitrate concentrations as an indicator of plasma NO level, were measured in the plasma of 20 subjects with exudative AMD and compared with 20 healthy age and sex matched controls. Mean plasma ET-1 level was significantly higher in exudative AMD patients as compared to control subjects (0.35 ± 0.06 fmol/ml versus 0.17 ± 0.03 fmol/ml, P = 0.015). Patients with exudative AMD also showed significantly lower mean plasma levels of nitrite plus nitrate as compared to the controls (58.9 ± 2.7 µmol/l versus 82.6 ± 5.9 µmol/l, P = 0.001). Increased concentrations of ET-1 and reduced levels of NO in the plasma may suggest an imbalance between vasoconstrictor and vasodilator agents, respectively, as a reflection of endothelial dysfunction in the pathogenesis of AMD. These findings may also imply the role of vasoconstriction in exudative AMD.

To investigate tumor necrosis factor (TNF)-α gene polymorphisms in advanced dry-type age-related macular degeneration (AMD) in a population from Northeastern Iran. In this case-control study, 50 patients with geographic macular atrophy and 73 gender-matched controls were enrolled. Genomic deoxyribonucleic acid (DNA) was extracted from the peripheral blood. Polymerase chain reaction was performed to analyze 2 candidate single nucleotide polymorphisms in the TNF-α gene, namely −1031 thymine (T)/cytosine (C) and −308 guanine (G)/adenine (A). The distribution of the - 1031 T/C genotype was TT, 62%; TC, 36%; CC, 2% in the patients and TT, 60%; TC, 36%; CC, 4% in the controls (P = 0.94). Genotype analysis of TNF-α −308 also revealed no significant difference in distribution between patients (G, 78%; GA, 22%; AA, 0%) and controls (GG, 74%; GA, 23%; AA, 3%) (P = 0.51). None of the haplotypes nor alleles of studied TNF-α polymorphisms were significantly associated with advanced dry-type AMD. The findings of this study show that polymorphisms in the TNF-α gene, do not play an important role in dry-type AMD in the studied population.

To evaluate retinal sensitivity over hard exudates in correlation with the spectral domain optical coherence tomography (SD-OCT) findings in eyes with diabetic retinopathy. Twelve eyes of 10 patients with hard exudates associated with diabetic retinopathy were enrolled in this study. All subjects underwent a complete ophthalmic examination including SD-OCT (Copernicus, Zawiercie, Poland) and microperimetry (MP1; Nidek Technologies, Padova, Italy). Retinal sensitivity was measured, over the areas with hard exudates and compared to corresponding locations devoid of hard exudates, using a semi-automatic program. The size of the hard exudate plaque was measured using the measurement software in the microperimeter. Retinal thickness in the area of the hard exudates and foveal thickness were measured using SD-OCT. Mean retinal sensitivity over hard exudates was 4.97 ± 4.17 dB which was significantly (P = 0.0001) reduced as compared to locations devoid of hard exudates. No significant correlation (r=-0.23, P = 0.45) was found between the size of the hard exudates and retinal sensitivity. A significant negative correlation was found between retinal sensitivity and retinal thickness at the area of the hard exudates (r=-0.65, P = 0.05), and between retinal sensitivity and foveal thickness (r=-0.91, P = 0.001). In eyes with diabetic retinopathy, retinal sensitivity was reduced due to the presence of hard exudates in the outer retinal layers and retinal thickening but this was not correlated with the size of the hard exudates.

To evaluate multifocal electroretinogram (mfERG) changes in eyes with diabetic macular edema (DME) and investigate any possible correlation with optical coherence tomography (OCT) features and visual acuity (VA). Twenty-nine right eyes of 29 subjects with DME due to non-proliferative diabetic retinopathy and 30 eyes of 30 normal subjects were evaluated. All patients underwent a complete ophthalmic examination. Sixty-one scaled hexagon mfERG responses were recorded. Components of thefirst order kernel of N1, N2, and P1 in five concentric rings centered on the fovea, were measured in both groups. Correlation and regression analyses were performed among VA, central macular thickness (CMT) based on OCT, mfERG amplitude, and latency of the N1, N2 and P1 waves. Significant differences were observed in all mfERG parameters in five-ring regions of the retina between eyes with DME versus controls (P < 0.05). There were significant correlations among VA with N2 (P = 0,001, b = 0.73) and P1 amplitudes (P = 0.001, b = −0.84) in the central macular area, and there was a borderline association between VA and CMT (P = 0.042, b = 0.392). Amplitudes of mfERG components (N1, P1, and N2) are significantly reduced and their latencies are delayed in eyes with DME indicating functional impairment in the outer retina. The mfERG total amplitude was significantly correlated with VA even more than CMT, therefore the combined use of OCT and mfERG for macular evaluation may better evaluate visual status in DME patients.

To evaluate foveal microstructural changes and to determine its association with visual outcomes after reattachment of rhegmatogenous retinal detachments (RRDs) by scleral buckling (SB) or pars plana vitrectomy (PPV). Using spectral domain optical coherence tomography (SD-OCT), foveal microstructure in eyes with macula-off RRD were studied 1, 3, 6, 9, 12 and 15 months after PPV or SB and correlated with visual outcomes. Forty-two eyes were included in the final analysis. Even with improved microstructural changes and normalization of retinal structures on OCT, final visual acuity was not correlated with microstructural changes in eyes undergoing PPV. In the SB group, final visual acuity was significantly correlated with an intact inner segment/outer segment (IS/OS) junction (P = 0.013). There was no significant correlation between final visual acuity and presence of subretinal fluid (SRF) in either group. After SB, eyes with an intact IS/OS junction had better final visual acuity. In the PPV group, there was no significant correlation between microstructural changes and visual acuity. The presence of SRF did not influence final visual acuity in both groups.

Dementia and glaucoma are both neurodegenerative conditions characterized by neuronal loss leading to cognitive and visual dysfunction, respectively. A variety of evidence exists linking the two diseases including structural signs, specifically degenerative changes within ganglion cells. Both diseases become more prevalent with increased age, but that alone is unlikely to account for the increased co-prevalence of the diseases found in various studies. Neurotoxic substances including abnormal hyperphosphorylated tau and amyloid-β have been found in both disease processes suggesting possible pathophysiologic links between the diseases. The exact mechanism of apoptosis, whether by direct toxicity or potentiation, still needs to be established, but could prove important for both diseases. Another potential link relates to low intracranial pressure in patients with both diseases causing a high translaminar pressure gradient and optic nerve damage in certain patients. While this alone may not account for direct optic nerve damage, it could lead to cerebrospinal fluid (CSF) circulatory failure causing increased neurotoxins along the optic nerves with resultant damage. All of this evidence suggests the need to further study links between the two diseases, as this could prove instrumental in understanding their overlapping pathophysiology and developing directed therapies for both diseases. While this is more thoroughly investigated, it may be prudent to have a lower threshold for a glaucoma work-up in patients with pre-existing dementia.

To report a case of herpes simplex virus (HSV) endotheliitis following simultaneous phacoemulsification, intraocular lens (IOL) implantation and descemet‘s membrane endothelial keratoplasty (DMEK). Case Report: A;45 year-old female with corneal endothelial decompensation and a mature cataract, and history of anterior uveitis underwent simultaneous phacoemulsification, IOL implantation and DMEK. Increased corneal edema and descemet‘s membrane (DM) detachment occurred on postoperative day 3 and 5, respectively. One week after surgery, active keratic precipitates (KPs) appeared. Polymerase chain reaction (PCR) analysis was performed on an aqueous sample which was positive for herpes simplex virus (HSV). After initiating oral acyclovir and frequent topical corticosteroids, the corneal edema resolved and the donor tissue became spontaneously reattached to the recipient corneal stroma. HSV endotheliitis may occur in the early postoperative period after DMEK and manifest as endothelial dysfunction leading to donor detachment. Anti-viral medication may help treat the acute phase and reduce the risk of recurrence.

To report three cases of optic nerve aplasia (ONA). Case Report: Herein three subjects with ONA are described, two subjects had unilateral involvement. In one of these cases, the fellow eye had an associated persistent hyperplastic primary vitreous (PHPV). The third patient had bilateral ONA with multiple intracranial anomalies. Previous reports are reviewed and reported findings are summarized. Orbital and brain magnetic resonance imaging (MRI) were normal in two of our cases and loss of corpus callosum in the third case. Narrow optic nerve was observed on the right side and normal appearance in other two patients. The diagnosis of optic nerve abnormalities in children requires a thorough ophthalmic examination and proper ancillary testing. Although MRI is valuable in the diagnosis of associated central nervous system anomalies, the optic nerve may appear in normal size and course on MRI images and thus one may not be able to diagnose ONA in eyes with opaque media.

To report three cases of optic nerve aplasia (ONA). Case Report: Herein three subjects with ONA are described, two subjects had unilateral involvement. In one of these cases, the fellow eye had an associated persistent hyperplastic primary vitreous (PHPV). The third patient had bilateral ONA with multiple intracranial anomalies. Previous reports are reviewed and reported findings are summarized. Orbital and brain magnetic resonance imaging (MRI) were normal in two of our cases and loss of corpus callosum in the third case. Narrow optic nerve was observed on the right side and normal appearance in other two patients. The diagnosis of optic nerve abnormalities in children requires a thorough ophthalmic examination and proper ancillary testing. Although MRI is valuable in the diagnosis of associated central nervous system anomalies, the optic nerve may appear in normal size and course on MRI images and thus one may not be able to diagnose ONA in eyes with opaque media.