Manifestaciones corneales en las enfermedades sistémicas

Systemic diseases affecting the cornea have a wide range of manifestations. The detailed study of all pathologies that cause corneal alteration is unapproachable, so we have centered our interest in the most prevalent or characteristic of them. In this paper we have divided these pathologies in sections to facilitate their study. Pulmonar and conective tissue (like colagen, rheumatologic and idiopathic inflamatory diseases), dermatologic, cardiovascular, hematologic, digestive and hepatopancreatic diseases with corneal alteration are described. Endocrine and metabolic diseases, malnutrition and carential states are also studied, as well as some otorhinolaryngologic and genetic diseases that affect the cornea. Finally, a brie

Optical Coherence Tomography Features of Active and Inactive Retinal Neovascularization in Proliferative Diabetic Retinopathy

PURPOSE: To describe spectral domain-optical coherence tomography features of retinal neovascularization in proliferative diabetic retinopathy and thus to identify novel signs of new vessel activity. METHODS: Retrospective, cross-sectional study. Data were collected over a 9-month period. Spectral domain optical coherence tomography scans were performed over areas of new vessel complexes (NVC) in both the disk and elsewhere, and were qualitatively graded by two masked observers. New vessel complexes activity was determined using clinical and angiographic criteria and correlated with spectral domain optical coherence tomography features. RESULTS: Forty-three eyes of 30 patients with proliferative diabetic retinopathy were included. Sixty-one NVC lesions (neovascularization of the disk—37.7%, neovascularization elsewhere—62.3%) were captured by spectral domain-optical coherence tomography and analyzed. Among them, 63.9% were classified as active and 36.1% as quiescent. Five distinctive features were identified as significantly different between active and quiescent NVC: the presence of vitreous hyperreflective dots in active NVC (P = 0.002) and the presence of epiretinal membrane (P = 0.04), inner retinal tissue contracture (P = 0.03), vitreous invasion (P = 0.02), and protrusion towards vitreous (P = 0.002) in quiescent NVC. CONCLUSION: In this exploratory study, the presence of vitreous hyperreflective dots, epiretinal membrane, inner retinal tissue contracture, vitreous invasion, and vitreous protrusion were identified as distinct signs of disease activity. Such parameters may be useful as a noninvasive imaging modality in eyes undergoing treatment for proliferative diabetic retinopathy

Cirrus high-definition optical coherence tomography compared with Stratus optical coherence tomography in glaucoma diagnosis

To compare the retinal nerve fiber layer (RNFL) evaluation using Cirrus optical coherence tomography (OCT) and Stratus OCT in glaucoma diagnosis. METHODS: One hundred thirty normal and 86 patients with glaucoma were included in this prospective study. The signal strengths of the OCTs were evaluated. The sensitivities and specificities of global RNFL average thickness were compared in the four quadrants and in each clock hour sector. Receiver operating characteristic (ROC) curves, areas under the ROC (AUC), and the likelihood ratio (LR) were plotted for RNFL thickness. Agreement between the OCTs was calculated by using the Bland-Altman method and kappa (kappa) coefficient. RESULTS: Twenty-three percent of all cases examined with Stratus OCT and 1.9% examined with Cirrus OCT had a signal strength below 6 (P = 0.01). In cases with signal strengths > or =6, the mean signal strength was higher with Cirrus OCT than with Stratus OCT (P = 0.01). The RNFL measurements by Cirrus were thicker than those of Stratus OCT (P < 0.05). The AUCs were 0.829 for Stratus and 0.837 for Cirrus OCT (P = 0.706) for global RNFL average. LRs were similar in both OCTs in global RNFL classification but varied in quadrants. The widths of the limits of agreement varied between 42.16 and 97.79 microm. There was almost perfect agreement (kappa = 0.82) in the average RNFL classification. CONCLUSIONS: Cirrus OCT has better scan quality than Stratus OCT, especially in glaucomatous eyes. In cases with good-quality scans, the sensitivity and specificity, and AUCs were similar. The best agreement was in the global average RNFL classification. The widths of limits of agreements exceed the limits of resolution of the OCTs

OCT angiography: a technique for the assessment of retinal and optic nerve diseases in the pediatric population

Optical coherence tomography angiography (OCT-A) is a novel, rapidly evolving, non-invasive imaging technique that allows images of the retinal vasculature to be obtained in a few seconds. Blood vessels of different retinal vascular plexuses and the foveal avascular zone (FAZ) can be examined without the administration of any contrast or dye. Due to these characteristics, OCT-A could be an excellent complementary test to study retinal vascularization in children. Until now, most of the studies with OCT-A have been conducted in adults and only a few have been carried out in children. In this review, we describe the principles and advantages of OCT-A over traditional imaging methods and provide a summary of the OCT-A findings in retinopathy of prematurity and other retinal and optic disc pathologies in children. In view of the promising results from studies, the advantages of a relatively rapid and non-invasive method to assess the retinal vasculature makes OCT-A a tool of which applications in the field of pediatric ophthalmology will be expanded in the near future for patient diagnosis and follow-up in every day clinical practice

Paracentral acute middle maculopathy after uneventful ocular surgery with local anaesthetic blocks

OBJECTIVE: To describe the role of local anaesthetic blocks as a potential cause of paracentral acute middle maculopathy (PAMM) after uneventful ocular surgery. METHODS: Retrospective, observational, international, multicentre case series. Nine cases of PAMM with associated visual loss following uneventful ocular surgery with local anaesthetic blocks were observed in a 9-year period (2011-2020). Demographic, ocular and systemic data, anaesthetic data and surgical details were collected. Visual acuity (VA), fundus photography, fluorescein angiography, optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) images were reviewed. RESULTS: All nine cases were associated with decreased VA at 24 h postoperative check (ranging from hand movement to 20/200). A hyperreflective band within the middle retinal layers was observed in the structural OCT in the acute phase, evolving to thinning and atrophy of the inner retinal layers in sequential follow-up scans performed. Fluorescein angiography showed delayed perfusion in early arterial phase with normal perfusion in late venous phases. OCTA showed decreased perfusion in the deep capillary plexus. Visual recovery was variable between cases during follow-up (ranging from count fingers to 20/20). CONCLUSIONS: A combination of a vasoconstrictive effect of the anaesthetic agent, an intraocular pressure spike and a mechanical effect of the volume of anaesthetic injected may result in decreased retinal artery perfusion and be evidenced as PAMM in OCT scans. PAMM may present as a potential complication of local anaesthetic blocks in cases of unexpected visual loss after uneventful ocular surgery

Acrysof® toric intraocular lens implantation in cataract surgery

Aim: To assess the medium term outcomes of Acrysof® toric intraocular lens implantation in 54 patients (54 eyes). Methods: Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), preoperative astigmatism, residual postoperative astigmatism, and global average and model-specific intraocular lens (IOL) rotation grade were analyzed. Results: At 2-months of follow-up,the mean UCVA was 0.83 (SD: 0.14) Snellen scale, with 73.9% of the patients ≥0.8, and 32.6% with 1.0. Mean BCVA achieved was 0.94 (SD: 0.10). Mean preoperatory astigmatism was –2.25 diopters (D) (SD: 0.78), and mean postoperative astigmatism was -0.32 D (SD: 0.56), with significant differences between both groups (p<0.001). Model-specific mean residual astigmatism was –0.1 D for T3, –0.27 D for T4 and –0.43 D for T5, without significant differences between the three models (p=0.483). Mean IOL-axis rotation grade was 3.87±3.25 degrees, with 91.6% of implanted lens within 10° of predicted axis. Discussion: T3, T4 and T5 Acrysof® Toric intraocular lenses can correct preoperative astigmatism with a high success rate in terms of UCVA, and residual postoperative astigmatism, with minimum IOL-rotation grade at 2 months follow-up period

Intravitreal bevacizumab associated with grid laser photocoagulation in macular edema secondary to branch retinal vein occlusion

To evaluate intravitreal bevacizumab (IVB) combined with grid laser photocoagulation in macular edema (ME) secondary to branch retinal vein occlusion (BRVO). METHODS: Eight eyes (8 patients) with ME associated with BRVO with at least 3 months of evolution since symptom onset were included. All subjects underwent measurement of best-corrected visual acuity (BCVA) and imaging with spectral domain optical coherence tomography (SD-OCT) at baseline and 1, 3, 6, and 12 months. Intravitreal bevacizumab was administered at baseline and macular grid laser photocoagulation 1 month later. During follow-up, additional IVB was administered based on physician discretion if persistent or recurrent intraretinal fluid (cysts) was observed on SD-OCT. The mean BCVA and SD-OCT central subfield thickness (CST) values were determined at each time point. Fisher exact test was performed to assess differences between baseline and post-treatment BCVA and SD-OCT measurements. RESULTS: The mean baseline BCVA was 0.28+/-0.14 (mean+/-SD), and the mean CST was 479+/-137 microm. The mean BCVAs at 1, 3, 6, and 12 months were 0.47+/-0.18 (p=0.031), 0.56+/-0.50 (p=0.031), 0.65+/-0.60 (p=0.008), and 0.66+/-0.65 (p=0.016), respectively. The mean CST values at 1, 3, 6, and 12 months were 295+/-60 microm (p=0.008), 333+/-114 microm (p=0.070), 339+/-80 microm (p=0.008), and 335+/-109 microm (p=0.008). A mean 2.13 injections were administered; the second injection was administered a mean of 2.71 months after baseline. CONCLUSIONS: Combined treatment with IVB and macular grid photocoagulation provided good results and may be considered as an alternative therapy for ME in BRVO. Further studies are needed to assess these preliminary results

The effects of macular ischemia on visual acuity in diabetic retinopathy

PURPOSE: To investigate the impact of diabetic macular ischemia (DMI) on visual acuity (VA), through the analysis of novel fluorescein angiography (FA) parameters. METHODS: Data were retrospectively collected over a 6-month period. DMI severity was graded using Early Treatment Diabetic Retinopathy Study (ETDRS) protocols. Custom software was used to quantify areas of the foveal avascular zone (FAZ), and of capillary nonperfusion over the papillo-macular nerve fiber layer bundle, and temporal macula, and associations tested with VA. RESULTS: A total of 488 patients with type 2 diabetes mellitus and FAs of sufficient quality to allow detailed quantitative analyses were included. ETDRS-DMI SEVerity was graded as: none, 39.7%; questionable, 18.4%; mild, 25.2%; moderate, 11.0%; and severe, 5.6%. Median FAZ areas were 0.19 mm(2) (interquartile range [IQR], 0.13-0.25); 0.25 mm(2) (IQR, 0.18-0.32); 0.27 mm(2) (IQR, 0.19-0.38); 0.32 mm(2) (IQR, 0.25-0.54); and 0.78 mm(2) (IQR, 0.60-1.32), respectively, and were significantly different between all grades (P < 0.002), apart from "questionable" versus "mild" grades. Significant association of VA to FAZ area was observed only in the moderate (β = 0.406, SE = 0.101, P = 0.001) and severe (β = 0.299, SE = 0.108, P = 0.006) subgroups, but not in milder ETDRS-DMI grades. A strong association with VA was observed in cases with papillomacular ischemia (β = 1.123, SE = 0.355, P = 0.005), independent of FAZ size or the presence of macular edema. CONCLUSIONS: Diabetic macular ischemia is associated with reduced VA in eyes with moderate to severe ETDRS-DMI grades of ischemia but preserved in milder grades. In addition, we describe the independent association of papillomacular nerve fiber bundle ischemia with reduced VA

Novel association of high C-reactive protein levels and A69S at risk alleles in wet age-related macular degeneration women

Purpose: To explore the relationship between plasma C-reactive protein (CRP) levels, the main ARMS2 gene single nucleotide polymorphism (SNP), and gender in patients with neovascular age-related macular degeneration (wet AMD). Methods: Our study included 131 patients with wetAMD [age-related eye disease study (AREDS) category 4] and 153 control participants (AREDS category 1) from two Spanish retinal units. CRP levels were determined on blood samples by high-sensitivity ELISA assay. According to their CRP level, subjects were categorized into three well-established CRP categories: low (3.00 mg/L, H-CRP). Genomic DNA was extracted from oral swabs using QIAcube (Qiagen, Hilden, Germany) and the A69S; rs10490924 of ARMS2 gene was genotyped by allelic discrimination with validated TaqMan assays (Applied Biosystems, Foster City, CA, USA). Univariate and multivariate logistic regression adjusted for age was used to analyze the genomic frequencies and to calculate odds ratio (OR) using SNPStats software. Results: Considering CRP risk categories, H-CRP group showed a significant [OR 4.0 (1.9-8.3)] association with wetAMD compared to L-CRP group. The risk genotypes of A69S (TT) SNPs showed an association with wetAMD risk [OR 14.0 (4.8-40.8)]. Interestingly, the gender stratification of the CRP categories showed a significant increase in CRP levels in wetAMD women compared with control women [OR 6.9 (2.2-22.3)] and with wetAMD men [OR 4.6 (1.3-16.9)]. In addition, the subgroup analysis of CRP within A69S genotype and gender showed a link in women between the A69S and CRP levels in the AMD group compared to controls [OR 4.2 (1.4-12.6)]. Conclusion: Our study shows, for the first time, that a different genetic association related with gender could contribute to AMD risk. As a consequence, the risk of female gender in the different CRP levels and A69S SNP frequencies could be taken into consideration to the established risk relationship of high levels of CRP and its association with risk A69S genotype

Optimizing OCT acquisition parameters for assessments of vitreous haze for application in uveitis

Detection and evaluation of inflammatory activity in uveitis is essential to the management of the condition, and yet continues to be largely dependent on subjective clinical measures. Optical coherence tomography (OCT) measurement of vitreous activity is an alternative to clinical vitreous haze scoring and has passed a number of early validation studies. In this study we aimed to evaluate the impact of ‘operator factors’ on the variability of the technique as part of the validation process, and to help evaluate its suitability for ‘real world’ use. Vitreous haze index was calculated as a ratio between the reflectivity of the vitreous and of the outer retina in each scan. Different scanning conditions were tested and their effect on the measurement is reported. Our results show that the ‘quantitative imaging’ technique of OCT-measured vitreous activity had good reliability in normal subjects under a range of ‘real world’ conditions, such as when the operator changes the averaging value. The technique was however vulnerable to highly inaccurate focussing or abnormal downward displacement of the image. OCT-based quantification of vitreous activity is a promising alternative to current subjective clinical estimates, with sufficient ‘tolerance’ to be used in routine clinical practice as well as clinical trials