Hydrostatic pressure does not cause detectable changes to survival of human retinal ganglion

Purpose: Elevated intraocular pressure (IOP) is a major risk factor for glaucoma. One consequence of raised IOP is that ocular tissues are subjected to increased hydrostatic pressure (HP). The effect of raised HP on stress pathway signaling and retinal ganglion cell (RGC) survival in the human retina was investigated. Methods: A chamber was designed to expose cells to increased HP (constant and fluctuating). Accurate pressure control (10-100mmHg) was achieved using mass flow controllers. Human organotypic retinal cultures (HORCs) from donor eyes (<24h post mortem) were cultured in serum-free DMEM/HamF12. Increased HP was compared to simulated ischemia (oxygen glucose deprivation, OGD). Cell death and apoptosis were measured by LDH and TUNEL assays, RGC marker expression by qRT-PCR (THY-1) and RGC number by immunohistochemistry (NeuN). Activated p38 and JNK were detected by Western blot. Results: Exposure of HORCs to constant (60mmHg) or fluctuating (10-100mmHg; 1 cycle/min) pressure for 24 or 48h caused no loss of structural integrity, LDH release, decrease in RGC marker expression (THY-1) or loss of RGCs compared with controls. In addition, there was no increase in TUNEL-positive NeuN-labelled cells at either time-point indicating no increase in apoptosis of RGCs. OGD increased apoptosis, reduced RGC marker expression and RGC number and caused elevated LDH release at 24h. p38 and JNK phosphorylation remained unchanged in HORCs exposed to fluctuating pressure (10-100mmHg; 1 cycle/min) for 15, 30, 60 and 90min durations, whereas OGD (3h) increased activation of p38 and JNK, remaining elevated for 90min post-OGD. Conclusions: Directly applied HP had no detectable impact on RGC survival and stress-signalling in HORCs. Simulated ischemia, however, activated stress pathways and caused RGC death. These results show that direct HP does not cause degeneration of RGCs in the ex vivo human retina

Comparison of age-specific cataract prevalence in two population-based surveys 6 years apart

BACKGROUND: In this study, we aimed to compare age-specific cortical, nuclear and posterior subcapsular (PSC) cataract prevalence in two surveys 6 years apart. METHODS: The Blue Mountains Eye Study examined 3654 participants (82.4% of those eligible) in cross-section I (1992–4) and 3509 participants (75.1% of survivors and 85.2% of newly eligible) in cross-section II (1997–2000, 66.5% overlap with cross-section I). Cataract was assessed from lens photographs following the Wisconsin Cataract Grading System. Cortical cataract was defined if cortical opacity comprised ≥ 5% of lens area. Nuclear cataract was defined if nuclear opacity ≥ Wisconsin standard 4. PSC was defined if any present. Any cataract was defined to include persons who had previous cataract surgery. Weighted kappa for inter-grader reliability was 0.82, 0.55 and 0.82 for cortical, nuclear and PSC cataract, respectively. We assessed age-specific prevalence using an interval of 5 years, so that participants within each age group were independent between the two surveys. RESULTS: Age and gender distributions were similar between the two populations. The age-specific prevalence of cortical (23.8% in 1(st), 23.7% in 2(nd)) and PSC cataract (6.3%, 6.0%) was similar. The prevalence of nuclear cataract increased slightly from 18.7% to 23.9%. After age standardization, the similar prevalence of cortical (23.8%, 23.5%) and PSC cataract (6.3%, 5.9%), and the increased prevalence of nuclear cataract (18.7%, 24.2%) remained. CONCLUSION: In two surveys of two population-based samples with similar age and gender distributions, we found a relatively stable cortical and PSC cataract prevalence over a 6-year period. The increased prevalence of nuclear cataract deserves further study

Adapted motivational interviewing to improve the uptake of treatment for glaucoma in Nigeria: study protocol for a randomized controlled trial.

BACKGROUND: Glaucoma is a chronic eye disease associated with irreversible visual loss. In Africa, glaucoma patients often present late, with very advanced disease. One-off procedures, such as laser or surgery, are recommended in Africa because of lack of or poor adherence to medical treatment. However, acceptance of surgery is usually extremely low. To prevent blindness, adherence to treatment needs to improve, using acceptable, replicable and cost-effective interventions. After reviewing the literature and interviewing patients in Bauchi (Nigeria) motivational interviewing (MI) was selected as the intervention for this trial, with adaptation for glaucoma (MIG). MI is designed to strengthen personal motivation for, and commitment to a specific goal by eliciting and exploring a person's reasons for change within an atmosphere of acceptance and compassion. The aim of this study is to assess whether MIG increases the uptake of laser or surgery amongst glaucoma patients where this is the recommended treatment. The hypothesis is that MIG increases the uptake of treatment. This will be the first trial of MI in Africa. METHODS: This is a hospital based, single centre, randomized controlled trial of MIG plus an information sheet on glaucoma and its treatment (the latter being "standard care") compared with standard care alone for glaucoma patients where the treatment recommended is surgery or laser.Those eligible for the trial are adults aged 17 years and above who live within 200 km of Bauchi with advanced glaucoma where the examining ophthalmologist recommends surgery or laser. After obtaining written informed consent, participants will be randomly allocated to MIG plus standard care, or standard care alone. Motivational interviewing will be delivered in Hausa or English by one of two MIG trained personnel. One hundred and fifty participants will be recruited to each arm. The primary outcome is the proportion of participants undergoing laser or surgery within two months of the date given to re attend for the procedure. MIG quality will be assessed using the validated MI treatment integrity scale. DISCUSSION: Motivational interviewing may be an important tool to increase the acceptance of treatment for glaucoma. The approach is potentially scalable and may be useful for other chronic conditions in Africa. TRIAL REGISTRATION: ISRCTN79330571 (Controlled-Trials.com)

The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE) : study protocol for a randomized controlled trial

Peer reviewedPublisher PD

Twenty-four-hour intraocular pressure and ocular perfusion pressure characteristics in newly diagnosed patients with normal tension glaucoma

PurposeTo determine the mean 24-h intraocular pressure (IOP) and mean ocular perfusion pressure (MOPP) characteristics of newly diagnosed, previously untreated, Caucasian, normal tension glaucoma (NTG) patients and to identify relationships between these features and visual field (VF) loss at diagnosis.MethodsConsecutive newly diagnosed NTG patients underwent 24-h habitual IOP and blood pressure (BP) monitoring. Parameters from pooled measurements obtained in the sitting (0800-2200 hours) and supine (1200-0600 hours) positions were compared and associations were sought with VF mean deviation (MD) and pattern standard deviation (PSD).ResultsSixty-two Caucasian NTG patients (24 men and 38 women) successfully completed circadian IOP and BP monitoring. In habitual position, 8 subjects (12.9%) exhibited a diurnal acrophase, 42 subjects (67.7%) demonstrated a nocturnal acrophase, one subject (1.6%) showed a flat rhythm and 11 patients (17.7%) revealed a biphasic/polyphasic rhythm. Nighttime MOPP values (supine position) were significantly greater than diurnal values (sitting position); (P<0.001). No association could be demonstrated between glaucomatous damage, as indicated by VF parameters, and either mean habitual 24-h IOP (P=0.20 and P=0.12 for MD and PSD, respectively), or habitual 24-h MOPP (P=0.96 and 0.29, for MD and PSD, respectively).ConclusionsIn this cohort of Caucasian NTG patients, most patients exhibited a nocturnal IOP acrophase when evaluated in a habitual position. No association was found between 24-h IOP or MOPP and VF damage.Eye advance online publication, 29 July 2016; doi:10.1038/eye.2016.168

Long-term remission of myopic choroidal neovascular membrane after treatment with ranibizumab: a case report

<p>Abstract</p> <p>Introduction</p> <p>Myopia has become a big public health problem in certain parts of the world. Sight-threatening complications like choroidal neovascularisation membranes occur in up to 10% of pathological myopia, and natural history studies show a trend towards progressive visual loss. There are long-term financial and quality-of-life implications in this group of patients, and treatment strategies should aim for long-term preservation of vision.</p> <p>Case presentation</p> <p>A 56-year-old Caucasian woman presented with a best-corrected visual acuity of 6/6-1 in her right eye and 6/24 in her left. Fundal examination revealed pathological myopia in both eyes and an elevated lesion associated with pre-retinal haemorrhage in the left macula. Ocular coherence tomography and fundus fluorescein angiogram confirmed a subfoveal classic choroidal neovascularisation membrane. The patient decided to proceed with intravitreal ranibizumab (0.5 mg) therapy. One month after treatment, best-corrected visual acuity improved to 6/12 in her left eye, with complete resolution subretinal fluid on ocular coherence tomography. After three months, best-corrected visual acuity further improved to 6/9, which was maintained up to 16 months post-treatment.</p> <p>Conclusion</p> <p>We suggest intravitreal ranibizumab as an alternative treatment for long-term remission of myopic choroidal neovascular membrane. It also suggests that myopic choroidal neovascularisation membranes may require fewer treatments to achieve sustained remission. Furthermore, this could serve as a feasible long-term management option if used in conjunction with ocular coherence tomography.</p

First-line latanoprost therapy in ocular hypertension or open-angle glaucoma patients: a 3-month efficacy analysis stratified by initial intraocular pressure

<p>Abstract</p> <p>Background</p> <p>Prospective, multicenter, randomized, double-masked trials have shown latanoprost instilled once daily to be at least as effective as and generally superior to timolol administered twice daily and to be as effective as other frequently prescribed prostaglandin analogues. This study prospectively assessed the efficacy of latanoprost monotherapy in a large cohort of treatment-naive patients with a broad range of baseline intraocular pressure (IOP) levels treated in actual clinical practice settings.</p> <p>Methods</p> <p>This prospective, open-label, multicenter, uncontrolled, phase IV study included treatment-naive ocular hypertension or open-angle glaucoma subjects initiating latanoprost once daily (evening). IOP levels were measured at baseline and after 1 and 3 months. The primary efficacy outcome was mean change in IOP from baseline to month 3. Analyses were stratified by baseline IOP: ≥ 20 and <24 mmHg <it>vs </it>≥ 24 mmHg.</p> <p>Results</p> <p>Efficacy analyses (intent to treat) included 572 subjects: 20 to <24 mmHg group, N = 252; ≥ 24 mmHg group, N = 320. Mean baseline IOP levels were 22.2 ± 0.9 mmHg and 26.7 ± 2.8 mmHg, respectively. At month 3, significant IOP reductions were seen in both groups (p < 0.0001, within-group differences); reductions were smaller in the 20 to <24 mmHg group (-6.3 ± 2.4 <it>vs </it>-9.2 ± 3.7 mmHg, respectively; -28.0 ± 10.6% <it>vs </it>-34.1 ± 11.9%, respectively). An IOP reduction of ≥ 30% from baseline to month 3 was noted in 48.4% and 65.6% of subjects, respectively (p < 0.0001). At month 3, targets IOPs of ≤ 18 mmHg were achieved by ≥ 70% of subjects in both groups. Latanoprost was well tolerated with an adverse event profile similar to that reported in the literature.</p> <p>Conclusions</p> <p>This "real world" study found once-daily latanoprost to be effective and safe in treatment-naive ocular hypertension or open-angle glaucoma patients. Patients with baseline IOP levels of 20 to <24 mmHg as well as ≥ 24 mmHg benefitted from initial latanoprost therapy.</p> <p>Trial Registration</p> <p>Trial Registration Number: NCT00647101</p

Ethnic Variation in the Prevalence of Visual Impairment in People Attending Diabetic Retinopathy Screening in the United Kingdom (DRIVE UK)

PURPOSE: To provide estimates of visual impairment in people with diabetes attending screening in a multi-ethnic population in England (United Kingdom). METHODS: The Diabetic Retinopathy In Various Ethnic groups in UK (DRIVE UK) Study is a cross-sectional study on the ethnic variations of the prevalence of DR and visual impairment in two multi-racial cohorts in the UK. People on the diabetes register in West Yorkshire and South East London who were screened, treated or monitored between April 2008 to July 2009 (London) or August 2009 (West Yorkshire) were included in the study. Data on age, gender, ethnic group, visual acuity and diabetic retinopathy were collected. Ethnic group was defined according to the 2011 census classification. The two main ethnic minority groups represented here are Blacks ("Black/African/Caribbean/Black British") and South Asians ("Asians originating from the Indian subcontinent"). We examined the prevalence of visual impairment in the better eye using three cut-off points (a) loss of vision sufficient for driving (approximately <6/9) (b) visual impairment (<6/12) and (c) severe visual impairment (<6/60), standardising the prevalence of visual impairment in the minority ethnic groups to the age-structure of the white population. RESULTS: Data on visual acuity and were available on 50,331 individuals 3.4% of people diagnosed with diabetes and attending screening were visually impaired (95% confidence intervals (CI) 3.2% to 3.5%) and 0.39% severely visually impaired (0.33% to 0.44%). Blacks and South Asians had a higher prevalence of visual impairment (directly age standardised prevalence 4.6%, 95% CI 4.0% to 5.1% and 6.9%, 95% CI 5.8% to 8.0% respectively) compared to white people (3.3%, 95% CI 3.1% to 3.5%). Visual loss was also more prevalent with increasing age, type 1 diabetes and in people living in Yorkshire. CONCLUSIONS: Visual impairment remains an important public health problem in people with diabetes, and is more prevalent in the minority ethnic groups in the UK