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Diabetic Macular Oedema (diabetic + macular_oedema)
Selected AbstractsDiabetic macular oedema: physical, physiological and molecular factors contribute to this pathological processACTA OPHTHALMOLOGICA, Issue 3 2010Rita Ehrlich Abstract. Diabetic macular oedema (DMO) is an important cause of vision loss in patients with diabetes mellitus. The underlying mechanisms of DMO, on both macrocellular and microcellular levels, are discussed in this review. The pathophysiology of DMO can be described as a process whereby hyperglycaemia leads to overlapping and inter-related pathways that play a role not only in the initial vascular events, but also in the continued tissue insult that leads to chronic DMO. On a macrocellular level, DMO is believed to be in part caused by alterations in hydrostatic pressure, oxygen tension, oncotic pressure and shear stress. Three key components of the microvascular pathways include angiogenic factor expression, inflammation and oxidative stress. These molecular mediators, acting in conjunction with macrocellular factors, which are all stimulated in part by the hyperglycaemia and hypoxia, can have a direct endothelial effect leading to hyperpermeability, disruption of vascular endothelial cell junctions, and leukostasis. The interactions, signalling events and feedback loops between the various molecules are complicated and are not completely understood. However, by attempting to understand the pathways involved in DMO, we can help guide new treatment options targeted towards specific factors or mediators. [source] Diabetic macular oedema and visual loss: relationship to location, severity and durationACTA OPHTHALMOLOGICA, Issue 7 2009Thomas W. Gardner Abstract. Purpose:, To assess the relationship between visual acuity (VA) and diabetic macular oedema (DMO) in relation to the location of retinal thickening and the severity and duration of central macular thickening. Methods:, Data from 584 eyes in 340 placebo-treated patients in the 3-years-long Protein Kinase C Diabetic Retinopathy Study (PKC-DRS2) trial were used to investigate the relationship between VA and DMO. Eligible eyes had moderately severe to very severe non-proliferative diabetic retinopathy and VA of at least 45 letters on Early Treatment Diabetic Retinopathy Study (ETDRS) charts (Snellen equivalent = 20/125). Diabetic retinopathy and DMO status were assessed using stereo photographs. Results:, Nearly one third of study eyes had foveal centre-involving DMO at the start of the trial. Sustained moderate visual loss was found in 36 eyes, most commonly associated with DMO at the centre of the fovea in 73% of eyes. There was a strong relationship (p < 0.001) between foveal centre involvement with DMO and mean VA. Mean VA decreased with increasing retinal thickness at the centre (p < 0.001) and increasing duration of centre-involving DMO (p < 0.001). Conclusion:, This study documents the relationship between duration of DMO and progressive vision loss, and the key role of central foveal involvement in patients with diabetic retinopathy. These data will help to develop future strategies to prevent vision loss. [source] A comparative evaluation of digital imaging, retinal photography and optometrist examination in screening for diabetic retinopathyDIABETIC MEDICINE, Issue 7 2003J. A. Olson Abstract Aims To compare the respective performances of digital retinal imaging, fundus photography and slit-lamp biomicroscopy performed by trained optometrists, in screening for diabetic retinopathy. To assess the potential contribution of automated digital image analysis to a screening programme. Methods A group of 586 patients recruited from a diabetic clinic underwent three or four mydriatic screening methods for retinal examination. The respective performances of digital imaging (n = 586; graded manually), colour slides (n = 586; graded manually), and slit-lamp examination by specially trained optometrists (n = 485), were evaluated against a reference standard of slit-lamp biomicroscopy by ophthalmologists with a special interest in medical retina. The performance of automated grading of the digital images by computer was also assessed. Results Slit-lamp examination by optometrists for referable diabetic retinopathy achieved a sensitivity of 73% (52,88) and a specificity of 90% (87,93). Using two-field imaging, manual grading of red-free digital images achieved a sensitivity of 93% (82,98) and a specificity of 87% (84,90), and for colour slides, a sensitivity of 96% (87,100) and a specificity of 89% (86,91). Almost identical results were achieved for both methods with single macular field imaging. Digital imaging had a lower technical failure rate (4.4% of patients) than colour slide photography (11.9%). Applying an automated grading protocol to the digital images detected any retinopathy, with a sensitivity of 83% (77,89) and a specificity of 71% (66,75) and diabetic macular oedema with a sensitivity of 76% (53,92) and a specificity of 85% (82,88). Conclusions Both manual grading methods produced similar results whether using a one- or two-field protocol. Technical failures rates, and hence need for recall, were lower with digital imaging. One-field grading of fundus photographs appeared to be as effective as two-field. The optometrists achieved the lowest sensitivities but reported no technical failures. Automated grading of retinal images can improve efficiency of resource utilization in diabetic retinopathy screening. Diabet. Med. 20, 528,534 (2003) [source] Pathogenesis of diabetic retinopathy and the renin-angiotensin systemOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 6 2003Hideharu Funatsu Abstract Despite the beneficial effects of good glycaemic control, loss of vision because of diabetic retinopathy (DR) still occurs. Recent studies have suggested that hypertension is a risk factor for the development and progression of DR and that blood pressure reduction can delay the progression of retinopathy. The renin-angiotensin system is activated by chronic hyperglycaemia, and the vitreous fluid level of angiotensin II (AII) is elevated in patients with proliferative diabetic retinopathy and diabetic macular oedema. AII increases vascular permeability and promotes neovascularization. It has been suggested that an autocrine-paracrine relationship may exist between AII and vascular endothelial growth factor in the ocular tissues. Accordingly, angiotensin-converting enzyme inhibitors or AII Type 1 (AT1) receptor blockers may be useful therapeutic agents for preventing the progression of DR. [source] Macular function after intravitreal triamcinolone acetonide injection for diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 5 2010Murat Karacorlu Abstract. Purpose:, We aimed to evaluate the effect of intravitreal triamcinolone acetonide (IVTA) on macular function in patients with diabetic macular oedema (DMO). Methods:, Eleven eyes in 11 patients with DMO were enrolled. In each eye, at baseline and at 30 days after IVTA injection, logMAR visual acuity (VA), macular sensitivity, fixation stability and fixation location by MP-1 microperimetry and optical coherence tomography (OCT) foveal thickness were assessed. Results:, Thirty days after IVTA injection, eyes with DMO showed a significant (p < 0.001) reduction in foveal thickness and significant (p < 0.01) increases in logMAR VA and MP-1 retinal sensitivity (p < 0.001). There was also significant (p = 0.046) improvement in fixation location and some improvement in fixation stability, although the latter was not significant (p = 0.08). Conclusions:, In eyes with DMO, short-term improvement in retinal sensitivity and fixation properties can be achieved by IVTA injection. [source] Steroid injection in addition to macular laser grid photocoagulation in diabetic macular oedema: a systematic reviewACTA OPHTHALMOLOGICA, Issue 4 2010Daan Steijns Abstract. Objectives:, This study aimed to evaluate the evidence for the effects of steroid injection in addition to macular laser grid (MLG) photocoagulation versus those of MLG photocoagulation alone on visual acuity (VA) in patients with diabetic macular oedema (DMO). Methods:, An extensive literature search in Medline (PubMed), Experta Medica (EMBASE) and the Cochrane Library (CENTRAL) using synonyms for MLG photocoagulation, steroid injection and DMO found 181 articles. Of the articles that met selection criteria, three studies in which patients receiving MLG photocoagulation were randomized to additional pretreatment with steroids provided the best available evidence. In addition to VA, central foveal thickness (CFT) was measured at baseline and at 6 months in all three studies. Results:, Two studies, with total populations of 73 and 42 eyes, respectively, reported no additional effect of steroid injection on VA. One study, with a total of 41 eyes, reported a beneficial effect of pretreatment with steroids on VA of , 0.21 ETDRS logMAR units. All three studies reported larger reductions in CFT in eyes pretreated with steroids, the smallest of which was 64 ,m. Conclusions:, Although there is a greater reduction in CFT in eyes pretreated with steroids, this does not consistently result in higher VA. The literature search does not provide sufficiently strong evidence to recommend steroid injection before MLG photocoagulation in DMO. [source] Vitrectomy may prevent the occurrence of diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 4 2010Audrey Navarro Abstract. Purpose:, This study aimed to demonstrate that vitrectomy may prevent the occurrence of diabetic macular oedema (DMO). Methods:, Three patients with diabetes type 1 underwent vitrectomy in one eye to treat complications of proliferative diabetic retinopathy. Results:, During follow-up, all patients suffered unilateral macular oedema in the non-vitrectomized eye as a result of general metabolic changes. In two of these patients, the DMO resolved with management of the underlying medical condition. Conclusions:, These case reports suggest the vitreous may play a role in the occurrence of DMO associated with general risk factors. Further studies are needed to increase understanding of the mechanisms involved in the development and progression of DMO. [source] Effect of acute postural variation on diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 2 2010Martin Vinten Abstract. Purpose:, This study aimed to study the pathophysiology of diabetic macular oedema (DMO) by analysis of concomitant changes in macular volume (MV), mean arterial blood pressure (MABP), intraocular pressure (IOP), and retinal artery and vein diameters in response to acute postural changes in patients with DMO and healthy subjects. Methods:, Thirteen patients with DMO (13 eyes) and five healthy subjects (five eyes) were examined after resting in a chair for 15 mins using optical coherence tomography to measure MV and fundus photography to assess retinal vessel diameters. The patients then lay down for 60 mins, during which they were examined repeatedly before they were reseated and examined again. Intraocular pressure was measured using pulse-air tonometry, arterial blood pressure by sphygomanometry and fluid columns using rulers and a spirit level. Results:, In healthy subjects, retinal artery (p = 0.02) and vein (p = 0.001) diameters decreased when subjects lay down, whereas MV remained stable. In patients with DMO, no orthostatic variation in retinal vessel diameters could be demonstrated, whereas MV had increased by 2.4 ± 0.6% (mean ± standard error of the mean; p = 0.006) 50 mins after assuming a recumbent position. In both healthy subjects and DMO patients, MABP decreased and IOP increased in a recumbent position, with no significant difference between the groups. Conclusions: The increase in MV that occurs in DMO when changing from a seated to a recumbent position is associated with a failure of retinal artery contraction, a response seen in healthy subjects that appears to counter-regulate the increase in ocular perfusion pressure caused by assuming a recumbent position. [source] Efficacy and safety of one intravitreal injection of bevacizumab in diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 2 2010Vinod Kumar No abstract is available for this article. [source] Efficacy and safety of one intravitreal injection of bevacizumab in diabetic macular oedema , authors' replyACTA OPHTHALMOLOGICA, Issue 2 2010Xiaoyun Fang No abstract is available for this article. [source] Diffuse diabetic macular oedema treated with intravitreal bevacizumab or triamcinolone acetonideACTA OPHTHALMOLOGICA, Issue 2 2010Florian Rensch No abstract is available for this article. [source] Diabetic macular oedema and visual loss: relationship to location, severity and durationACTA OPHTHALMOLOGICA, Issue 7 2009Thomas W. Gardner Abstract. Purpose:, To assess the relationship between visual acuity (VA) and diabetic macular oedema (DMO) in relation to the location of retinal thickening and the severity and duration of central macular thickening. Methods:, Data from 584 eyes in 340 placebo-treated patients in the 3-years-long Protein Kinase C Diabetic Retinopathy Study (PKC-DRS2) trial were used to investigate the relationship between VA and DMO. Eligible eyes had moderately severe to very severe non-proliferative diabetic retinopathy and VA of at least 45 letters on Early Treatment Diabetic Retinopathy Study (ETDRS) charts (Snellen equivalent = 20/125). Diabetic retinopathy and DMO status were assessed using stereo photographs. Results:, Nearly one third of study eyes had foveal centre-involving DMO at the start of the trial. Sustained moderate visual loss was found in 36 eyes, most commonly associated with DMO at the centre of the fovea in 73% of eyes. There was a strong relationship (p < 0.001) between foveal centre involvement with DMO and mean VA. Mean VA decreased with increasing retinal thickness at the centre (p < 0.001) and increasing duration of centre-involving DMO (p < 0.001). Conclusion:, This study documents the relationship between duration of DMO and progressive vision loss, and the key role of central foveal involvement in patients with diabetic retinopathy. These data will help to develop future strategies to prevent vision loss. [source] Intravitreal pegaptanib sodium (Macugen®) for diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 6 2009Giuseppe Querques Abstract. Purpose:, To report the functional and anatomical outcomes resulting from the use of intravitreal pegaptanib sodium (Macugen®) in patients with diabetic macular oedema (DMO). Methods:, We conducted a retrospective outcome analysis, by optical coherence tomography (OCT) and best-corrected visual acuity (BCVA), of eyes with DMO treated with intravitreal pegaptanib sodium. Moreover, we evaluated the foveal transverse photoreceptor (PR) band integrity in the OCT images at the time of the last follow-up visit. Results:, Sixty-three eyes of 48 patients with a minimum of 6 months of follow-up were included for analysis. Intravitreal pegaptanib was found to produce significant improvements in mean BCVA (p = 0.019) and reductions in mean central macular thickness (CMT) (p < 0.001) as soon as the 6-week follow-up. Most eyes (60/63) required a mean of 3.03 ± 0.9 repeated treatments, over a mean follow-up period of 6.7 ± 1.2 months, to achieve significant improvements in mean BCVA (p < 0.001) and mean CMT (p < 0.001). In our series, the lower visual acuities tended to congregate in the group with the less-defined PR band (p < 0.001) and the lower CMT tended to congregate in the group with the best-defined PR band (p = 0.04), even though the higher CMT did not tend to congregate in the group with the less-defined PR band. Conclusion:, Our findings demonstrate that selective inhibition by intravitreal pegaptanib sodium of vascular endothelial growth factor (VEGF)-165 may produce a clinically meaningful and statistically significant benefit in the treatment of DMO. [source] Rapid reduction of hard exudates in eyes with diabetic retinopathy after intravitreal triamcinolone: data from a randomized, placebo-controlled, clinical trialACTA OPHTHALMOLOGICA, Issue 3 2009Jörgen Larsson Abstract. Purpose:, To assess the effect of triamcinolone acetonide over 3 months on hard exudates in patients with diabetic macular oedema (DMO). Methods:, Thirty-two eyes of 16 patients with DMO and hard exudates were included in a randomized, placebo-controlled trial. Treated eyes received a single-dose (4 mg) intravitreal injection of triamcinolone acetonide. Control eyes received an injection of subconjunctival saline. Results:, The overall area of hard exudates decreased significantly between the baseline and 3-month visits in treated eyes, but not in control eyes. The mean change in level of hard exudates between the two visits was , 0.75 arbitrary units (AU) (95% confidence interval [CI] , 1.32 to , 0.18) in the central plus inner circle (1500 ,m) and , 0.81 AU (95% CI , 1.49 to , 0.13) over the whole grid (3000 ,m) in treated eyes, compared with 0.31 AU (95% CI , 0.19 to 0.82) and 0.31 AU (95% CI , 0.11 to 0.74), respectively, in control eyes (p < 0.001). Mean visual acuity improved by five letters in treated but not in control eyes (p = 0.01). Conclusions:, Intravitreal triamcinolone reduces hard exudates in the short-term in eyes with DMO. [source] Short wavelength automated perimetryACTA OPHTHALMOLOGICA, Issue 6 2001John M. Wild ABSTRACT. Short Wavelength Automated Perimetry (SWAP) utilizes a blue stimulus to preferentially stimulate the blue cones and a high luminance yellow background to adapt the green and red cones and to saturate, simultaneously, the activity of the rods. This review describes the theoretical aspects of SWAP, highlights current limitations associated with the technique and discusses potential clinical applications. Compared to white-on-white (W-W) perimetry, SWAP is limited clinically by: greater variability associated with the estimation of threshold, ocular media absorption, increased examination duration and an additional learning effect. Comparative studies of SWAP and W-W perimetry have generally been undertaken on small cohorts of patients. The conclusions are frequently unconvincing due to limitations for SWAP in the delineation of abnormality and of progressive field loss. SWAP is almost certainly able to identify glaucomatous visual field loss in advance of that by W-W perimetry although the incidence of progressive field loss is similar between the two techniques. Increasing evidence suggests that functional abnormality with SWAP is preceded by structural abnormality of the optic nerve head and/or the retinal nerve fibre layer. SWAP appears to be beneficial in the detection of diabetic macular oedema and possibly in some neuro-ophthalmic disorders. [source] Triamcinolone-induced cataract in eyes with diabetic macular oedema: 3-year prospective data from a randomized clinical trialCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 6 2010Mark C Gillies FRANZCO PhD Abstract Purpose:, To describe the 3-year risk of cataract after intravitreal triamcinolone (IVTA) injections for diabetic macular oedema and the outcomes of cataract surgery. Methods:, Prospective data from a randomized clinical trial were analysed. At baseline, 27 phakic eyes with diabetic macular oedema were randomized to receive IVTA and 25 to receive sham injection. After 2 years, initial sham-treated eyes were eligible to receive IVTA as the study became open label for the third year. The cumulative incidence of cataract surgery was the primary outcome of the study. Other outcomes assessed included progression of cataract, best-corrected logarithm of the minimal angle of resolution visual acuity before and after surgery and central macular thickness. Results:, Over the 3 years of the study, 15/27 (56%) phakic eyes in the IVTA treated group underwent cataract surgery as compared with 2/25 (8%) initial sham-treated eyes (P < 0.001). Mean visual acuity 6 months after cataract surgery was better than at entry into the trial. Two (15%) of the eyes in the IVTA-treated group undergoing cataract surgery had a loss of >15 letters. In the IVTA-treated group, 10/15 (67%) eyes that had three or more injections had progression of posterior subcapsular cataract by ,2 grades as compared with only 2/12 (17%) eyes that had fewer than three injections (P = 0.009). Conclusions:, Over half of the eyes receiving IVTA injections for diabetic macular oedema required cataract surgery within 3 years. In eyes with three or more IVTA injections, two-thirds had progression of posterior subcapsular cataract. Visual outcomes after cataract surgery were generally good, although a small proportion of eyes lost greater than 15 letters over the course of the study. [source] Factors associated with variability in response of diabetic macular oedema after intravitreal triamcinoloneCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 6 2009MRCOphth, Shaheeda Mohamed MPH Abstract Purpose:, To identify factors associated with variability in anatomical and functional response of diabetic macular oedema (DMO) after 4 mg of intravitreal triamcinolone acetonide (ivTA), and for recurrence of macular oedema. Design:, Pooled analysis of individual data from two randomized controlled trials. Methods:, This was a multicentre study involving 107 eyes with DMO administered 4 mg ivTA. Predictive factors for response to treatment were evaluated with linear regression analysis. Factors associated with time to recurrence of oedema were studied with Cox proportional hazards modelling. Main outcome measures were maximum improvement in optical coherence tomography (OCT)-measured central foveal thickness (CFT) and best-corrected visual acuity (BCVA), final CFT and BCVA at 12 months and time to oedema recurrence. Results:, Greater reduction of retinal thickening occurred in eyes with worse baseline thickening (P < 0.001). There was also greater improvement of visual acuity in eyes with poorer preoperative BCVA levels (P < 0.001). Age, duration of oedema and previous macular laser treatment had no significant effect on maximal BCVA or CFT improvement. Eyes given 4 mg triamcinolone alone were more likely to develop recurrence of oedema at 12 months than those given a combination of 4 mg triamcinolone plus sequential laser (hazard ratio 2.60 [95% confidence interval: 1.45,4.67]). Conclusion:, Baseline OCT-measured retinal thickening and BCVA are important predictors of maximal anatomical and functional response of DMO to ivTA, respectively. Combination treatment strategy using sequential laser therapy may have a role in delaying recurrence of oedema after triamcinolone. [source] | ||||||||||