Risk Of Permanent Visual Impairment Research Articles

An Anatomical Feasibility Study for Revascularization of the Ophthalmic Artery. Part II: Intraorbital Segment

Distal ophthalmic artery (OpA) aneurysms are a rare subset of vascular lesions with lack of optimal treatment. The management of these aneurysms may require complete occlusion of the parent vessel, carrying a risk of permanent visual impairment due to individual variations of extracranial collateral flow to the intraorbital ophthalmic artery (iOpA). To test the feasibility of a superficial temporal artery (STA) to iOpA bypass to prevent acute ischemic retinal injury. Two different transorbital corridors (superomedial and posterolateral approaches) for this bypass were evaluated. Each approach was carried out in 10 specimens each (n= 20). The corridors were compared to achieve the optimal exposure of the iOpA until the central retinal artery origin was visualized. An end-to-end anastomosis was performed from STA-to-iOpA. The arterial caliber and length at the anastomotic sites, required donor artery length, and intraorbital surgical area were measured. STA-iOpA bypasses were performed in all specimens. For the posterolateral transorbital approach, the mean caliber of STA was 1.8 ± 0.2 mm, and that of iOpA was 1.7 ± 0.5 mm. The required STA graft length was 78.3 ± 1 mm with lateral iOpA transposition of 8.2 ± 1.1 mm. For the superomedial approach, the average STA length required for an intraorbital bypass was 130.8 ± 14.0 mm. The mean calibers of iOpA and STA were 1.5 ± 0.1 mm and 1.5 ± 0.1 mm, respectively. This study demonstrates the feasibility of a novel revascularization technique of the iOpA using 2 different transorbital approaches. These techniques can be used in the management of intraorbital lesions such as OpA aneurysms, tumoral infiltrations, or intraoperative injuries.

Antibiotic treatment for ocular toxoplasmosis: a systematic review and meta-analysis: study protocol

BackgroundOcular toxoplasmosis (OT) is the most common cause of posterior uveitis, leading to visual impairment in a high proportion of patients. Antibiotics and corticosteroids lower the risk of permanent visual impairment by reducing the size of the retinochoroidal scar, the risk of recurrence, and the severity and duration of acute symptoms. Although OT is a very common cause of infectious posterior uveitis, its treatment remains controversial. Through our systematic review and meta-analysis, we aim to provide the best possible evidence-based information on the safety and effectiveness of the different antibiotic regimes for OT.MethodsThis systematic review protocol has been developed based on PRISMA-P guidelines for reporting systematic reviews evaluating health care interventions. We will include all published and unpublished randomized controlled trials (RCTs) comparing different antibiotics used for the treatment of OT. We will consider changes in visual acuity, number of recurrences, improvement or worsening of ocular inflammation, size of lesion, and adverse effects as our outcomes. Screening, data extraction, and quality assessment will be undertaken by two reviewers with disagreements resolved through discussion. Studies that compared antibiotics with placebo will be excluded. The reviews will be assessed for quality and relevance. We will assess the risk of bias in five domains according to Cochrane group’s tool. The type of data will dictate measures of treatment effect. We will use a random-effects model to calculate our meta-analysis, as eligible studies represent clinically varied populations of participants.DiscussionThe strength of our study will lie in the exhaustive and systematic nature of the literature search, as well as in its methods for assessing quality and analyzing RCT data. Considering the controversial efficacy of the treatment for OT, our study will contribute to improving the existing evidence on the effectiveness of different antibiotics. Future studies may be conducted to increase physicians’ awareness of antibiotic therapies, improving the health of patients with OT.Systematic review registrationPROSPERO CRD42018085468.

Loss of pRB in Conjunctival Squamous Cell Carcinoma: A Predictor of Poor Prognosis.

Conjunctival squamous cell carcinoma (SCC) is the most common tumor of conjunctival epithelium. It is associated with risk of permanent visual impairment and has the capability to recur, metastasize, and cause death. Deregulation of cell cycle control has been reported in a number of malignancies. The aim of the present study was to assess expression of G1/S cell cycle regulatory proteins [retinoblastoma protein (pRb)/P16/cyclin D1] in conjunctival SCC. Forty-four prospective cases of conjunctival SCC from a tertiary eye care referral center in northern India were included in this study. American Joint Committee on Cancer (AJCC) staging was performed and patients were followed up for 46±3.2 months. pRb loss was seen in 87% and overexpression of p16 and cyclin D1 in 36% and 66%, respectively. Kaplan-Meier analysis revealed reduced disease-free survival in patients with pRb loss (P=0.006). On univariate analysis, pRb loss (P=0.02), orbital invasion (P=0.03), and AJCC stage ≥T3 (P=0.03) emerged as significant high-risk features. On multivariate analysis pRb loss emerged as the most significant poor prognostic indicator in conjunctival SCC cases. Our findings suggest pRb loss to be a useful indicator of aggressive behavior and is recommended for identifying high-risk conjunctival SCC patients.

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The use of many drugs in dermatologic diseases may cause ocular side effects. Some may regress after discontinuation of the therapy, but others persist or progress even after the cessation of treatment. This review presents four groups of commonly prescribed drugs—antimalarial medicines, glucocorticoids, retinoids, and psoralens + ultraviolet A (UVA) therapy—and discusses their possible ocular side effects.The most significant complication of antimalarial drugs is retinopathy with the risk of permanent visual impairment. There are different recommendations for screening for this drug-related retinopathy. The most important ocular manifestations of steroid management are irreversible optic nerve damage in “steroid responders” (steroid glaucoma) and cataract. Some other side effects may disappear after discontinuation of the therapy. Retinoid-induced ocular side effects include ocular surface disease as well as retinal dysfunction. It is recommended to modify the therapy when night blindness occurs or after the decrease of color vision. Protective eyewear is sufficient to avoid ocular surface problems during psoralen + UVA therapy.The knowledge of screening schemes and closer cooperation between physicians may decrease the risk of serious or irreversible ocular side effects.

Ocular changes induced by drugs commonly used in dermatology

The use of many drugs in dermatologic diseases may cause ocular side effects. Some may regress after discontinuation of the therapy, but others persist or progress even after the cessation of treatment. This review presents four groups of commonly prescribed drugs—antimalarial medicines, glucocorticoids, retinoids, and psoralens + ultraviolet A (UVA) therapy—and discusses their possible ocular side effects.The most significant complication of antimalarial drugs is retinopathy with the risk of permanent visual impairment. There are different recommendations for screening for this drug-related retinopathy. The most important ocular manifestations of steroid management are irreversible optic nerve damage in “steroid responders” (steroid glaucoma) and cataract. Some other side effects may disappear after discontinuation of the therapy. Retinoid-induced ocular side effects include ocular surface disease as well as retinal dysfunction. It is recommended to modify the therapy when night blindness occurs or after the decrease of color vision. Protective eyewear is sufficient to avoid ocular surface problems during psoralen + UVA therapy.The knowledge of screening schemes and closer cooperation between physicians may decrease the risk of serious or irreversible ocular side effects.

The fast-track ultrasound clinic for early diagnosis of giant cell arteritis significantly reduces permanent visual impairment: towards a more effective strategy to improve clinical outcome in giant cell arteritis?

Permanent visual impairment has been reported to occur in up to 19% of GCA patients. The aim of this study was to examine whether implementation of a fast-track approach could reduce the rate of permanent visual impairment and inpatient days of care in GCA patients. A fast-track outpatient GCA clinic (FTC) was implemented in the Department of Rheumatology, Hospital of Southern Norway Trust Kristiansand, Norway in 2012. The patients included in this study were subsequently recruited between March 2010 and October 2014. Routine clinical and laboratory data and number of inpatient days of care were collected. During the observation period, 75 patients were diagnosed with GCA. Among the 75 GCA patients, 32 were evaluated conventionally and 43 in the FTC. In the conventionally approached group, six patients suffered from permanent visual impairment, while in the FTC group only one patient suffered from permanent visual impairment. The relative risk of permanent visual impairment in the GCA patients examined in the FTC was 88% lower compared with the conventionally evaluated group (relative risk 0.12, 95% CI: 0.01, 0.97, P = 0.01). The mean difference in inpatient days of care between patients evaluated conventionally and patients evaluated in the FTC was 3 days (3.6 vs 0.6 days, P < 0.0005). The implementation of the FTC in GCA care appears to significantly reduce the risk of permanent visual impairment and is more cost effective by reducing the need for inpatient care.

Abstract A03: Epigenetic alterations of stratifin in ocular surface squamous neoplasia: Pathogenesis and prognosis

Abstract Purpose: Ocular Surface Squamous neoplasia (OSSN) is the most common tumor of conjunctival epithelium associated with risk of permanent visual impairment. It includes conjunctival intraepithelial neoplasia (CIN) and squamous cell carcinoma (SCC).Of the multifactorial etiopathogenesis of OSSN, ultraviolet irradiation has been reported as a major risk factor in the pathogenesis of OSSN. Sunlight induced p53 mutations are known to contribute towards increased risk of OSSN. Stratifin (14-3-3σ)/HEM (human epithelial marker) is a p53 mediated inhibitor of cell cycle progression and has been shown to be a target of epigenetic deregulation in various carcinomas. In the present study, Stratifin expression, its promoter methylation status and expression of mutant p53 in OSSN was studied. The significance of Stratifin and p53 in the pathogenesis and prognosis of ocular surface squamous neoplasia (OSSN) patients was also evaluated. Methods: Sixty-four histopathologically confirmed OSSN cases (44 SCC and 20 CIN) were included in this study. AJCC TNM staging was performed and patients were followed up for 32 months. Immunohistochemical expression of Stratifin (clone-ab14123) and mutant p53 (clone-DO7) protein was evaluated; methylation status of Stratifin was determined by methylation specific PCR using specific primers. Kaplan–Meier survival and Cox regression analysis was done to assess the prognostic significance of Stratifin and p53. Results: Loss of Stratifin immunoexpression was observed in 75% (48/64) and 48% (31/64) cases showed mutant p53 expression. Hypermethylation of Stratifin promoter was seen in 63% (40/64) OSSN cases. Of the 48 cases with loss of Stratifin expression, promoter hypermethylation was seen in 35% (17/48), mutant p53 expression in 10% (5/48) and both promoter hypermethylation and mutant p53 expression in 58% (23/48) cases. These results indicate that both hypermethylation of Stratifin and mutant p53 expression are associated with loss of Stratifin in OSSN cases. On statistical analysis, Stratifin loss was significantly associated with tumor size &amp;gt;2cm, T3 and T4 category, poor histopathological differentiation of SCC and reduced disease free survival (P 0.05). Cox analysis showed Stratifin to be an independent prognostic marker for OSSN (p =0.03) patients. Mutant p53 expression was associated with history of longer sunlight exposure in 56% cases. No significant correlation was observed between mutant p53 expression and other clinicopathological feature or clinical outcome. Conclusions: Our results indicate that loss of Stratifin is a key event in the pathogenesis of OSSN. Presence of both aberrant methylation of Stratifin and mutant p53 expression implicates involvement of p53-Stratifin mediated signalling pathway in the pathogenesis of OSSN. Stratifin loss may also prove to be a useful biomarker for identifying high risk OSSN patients. Citation Format: Sheetal Chauhan, Seema Sen, Anjana Sharma, Shyam S. Chauhan, Seema Kashyap, Radhika Tandon, Neelam Pushker, M Vanathi. Epigenetic alterations of stratifin in ocular surface squamous neoplasia: Pathogenesis and prognosis. [abstract]. In: Proceedings of the Third AACR International Conference on Frontiers in Basic Cancer Research; Sep 18-22, 2013; National Harbor, MD. Philadelphia (PA): AACR; Cancer Res 2013;73(19 Suppl):Abstract nr A03.

Ultraviolet Radiation and the Role of Matrix Metalloproteinases in the Pathogenesis of Ocular Surface Squamous Neoplasia

Ocular surface squamous neoplasia (OSSN) is an uncommon tumor of the corneal and conjunctival epithelium associated with risk of permanent visual impairment. The purposes of this study were to (1) identify and localize potential mediators in tissue from patients with OSSN and (2) culture human dysplastic conjunctival epithelial cells (DCECs) to determine their responsiveness to ultraviolet (UV)-B radiation compared with normal conjunctival epithelial cells (NCECs). Immunohistochemical analysis was performed on OSSN (n = 23) and normal conjunctival (n = 17) tissue to identify matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Cell viability as well as basal and UVB-modulated levels of MMPs and TIMPs from DCECs and NCECs was determined by immunoassays, zymography, and RT-PCR. A higher proportion of diseased specimens stained for MMP-1 (83%), MMP-3 (86%), TIMP-2 (87%), and TIMP-3 (83%) compared with normal conjunctiva (41%, 41%, 47%, and 53%, respectively). UVB radiation induced cell death and apoptosis at doses >/= 50 mJ/cm(2). MMP-1 and -3 mRNA and protein expression in DCECs was induced by UV and was mitogen-activated protein kinase-dependent, although the same enzymes were upregulated in NCECs only at doses that induced apoptosis. TIMP-1 and -2 levels remained relatively unchanged, except for a dose-dependent suppression of TIMP-3. The results suggest that MMPs and TIMPs play a significant role in the pathogenesis of OSSN and that UVB initiates and perpetuates the development of this lesion on the ocular surface.

Papilledema Associated with Dialysis Disequilibrium Syndrome

The purpose of this paper is to report a case of dialysis disequilibrium syndrome as an unusual cause of papilledema. A 38-year-old woman with type 1 diabetes mellitus presented with decreased visual acuity and bilateral optic nerve swelling associated with systemic signs and symptoms of dialysis disequilibrium syndrome. Repeated lumbar punctures revealed elevated intracranial pressures. She was placed on acetazolamide with some improvement in symptoms. After renal transplantation, the patient had complete resolution of headaches, nausea and the papilledema. Our conclusion is that patients with visual disturbance and focal neurological symptoms during and after hemodialysis should be suspected of having dialysis disequilibrium syndrome (DDS). DDS is thought to occur as a result of a rapid reduction in plasma osmolality during dialysis. As the shift of urea from cerebral spinal fluid (CSF) is delayed, the relative increase in CSF osmolality draws fluid into the brain. The ensuing cerebral edema is responsible for the characteristic neurological symptoms. We report the association of papilledema with this syndrome, and caution as to the possible concurrent risk of permanent visual impairment.

Quinolones in dermatology

The use of many drugs in dermatologic diseases may cause ocular side effects. Some may regress after discontinuation of the therapy, but others persist or progress even after the cessation of treatment. This review presents four groups of commonly prescribed drugs—antimalarial medicines, glucocorticoids, retinoids, and psoralens + ultraviolet A (UVA) therapy—and discusses their possible ocular side effects.The most significant complication of antimalarial drugs is retinopathy with the risk of permanent visual impairment. There are different recommendations for screening for this drug-related retinopathy. The most important ocular manifestations of steroid management are irreversible optic nerve damage in “steroid responders” (steroid glaucoma) and cataract. Some other side effects may disappear after discontinuation of the therapy. Retinoid-induced ocular side effects include ocular surface disease as well as retinal dysfunction. It is recommended to modify the therapy when night blindness occurs or after the decrease of color vision. Protective eyewear is sufficient to avoid ocular surface problems during psoralen + UVA therapy.The knowledge of screening schemes and closer cooperation between physicians may decrease the risk of serious or irreversible ocular side effects.

Risk, causes, and outcomes of visual impairment after loss of vision in the non-amblyopic eye: a population-based study

Screening for amblyopia in early childhood is done in many countries to ensure that affected children are detected and treated within the critical period, and achieve a level of vision in their amblyopic eye that would be useful should they lose vision in their non-amblyopic eye later in life. We aimed to investigate the risk, causes, and outcomes of visual impairment attributable to loss of vision in the non-amblyopic eye. For 24 months from July, 1997, national surveillance was done to identify all individuals in the UK with unilateral amblyopia (acuity worse than 6/12) who had newly acquired vision loss in the non-amblyopic eye, resulting in acuity of worse than 6/12 or visual-field restriction precluding driving. Information about participants was obtained at presentation and 1 year later. Participants were categorised as having socially significant visual impairment, or visual impairment, severe visual impairment, or blindness, in accordance with WHO taxonomy. Of 370 eligible individuals, at presentation 104 (28%) had socially significant visual impairment, 180 (49%) visual impairment, and 86 (23%) severe visual impairment or blindness. The minimum risk of permanent visual impairment by age 95 years was 32.9 (95% CI 29.1-36.9) per 100,000 total population. The projected lifetime risk of vision loss for an individual with amblyopia was at least 1.2% (95% CI 1.1-1.4). Only 36 (35%) of 102 people previously in paid employment were able to continue. In the UK, where screening for amblyopia is under review, risk of serious vision loss affecting the non-amblyopic eye and its results are greater than that previously assumed. Thus, in addition to the benefits of improved vision in the amblyopic eye, treatment of amblyopia during childhood is a potentially valuable strategy to prevent incapacitating vision loss later in life.