Visual field defects and retinal nerve fiber imaging in patients with obstructive sleep apnea syndrome and in healthy controls.

BACKGROUND: To assess the retinal sensitivity in obstructive sleep apnea hypopnea syndrome (OSAHS) patients evaluated with standard automated perimetry (SAP). And to correlate the functional SAP results with structural parameters obtained with optical coherence tomography (OCT). METHODS: This prospective, observational, case-control study consisted of 63 eyes of 63 OSAHS patients (mean age 51.7 ± 12.7 years, best corrected visual acuity ≥20/25, refractive error less than three spherical or two cylindrical diopters, and intraocular pressure < 21 mmHg) who were enrolled and compared with 38 eyes of 38 age-matched controls. Peripapillary retinal nerve fiber layer (RNFL) thickness was measured by Stratus OCT and SAP sensitivities and indices were explored with Humphrey Field Analyzer perimeter. Correlations between functional and structural parameters were calculated, as well as the relationship between ophthalmologic and systemic indices in OSAHS patients. RESULTS: OSAHS patients showed a significant reduction of the sensitivity for superior visual field division (p = 0.034, t-student test). When dividing the OSAHS group in accordance with the severity of the disease, nasal peripapillary RNFL thickness was significantly lower in severe OSAHS than that in controls and mild-moderate cases (p = 0.031 and p = 0.016 respectively, Mann-Whitney U test). There were no differences between groups for SAP parameters. We found no correlation between structural and functional variables. The central visual field sensitivity of the SAP revealed a poor Pearson correlation with the apnea-hipopnea index (0.284, p = 0.024). CONCLUSIONS: Retinal sensitivity show minor differences between healthy subjects and OSAHS. Functional deterioration in OSAHS patients is not easy to demonstrate with visual field examination.

Calculation of iris-claw IOL power for correction of late in-the-bag IOL complex dislocation.

BACKGROUND: To assess the constants and formula for aphakia correction with iris-claw IOLs to achieve the best refractive status in cases of late in-the-bag IOL complex dislocation. METHODS: A literature search was performed. The following data were obtained: Iris-claw IOL model, Iridal or retroiridal enclavation, A-constant, ultrasound or optical biometry, formula employed and refractive outcomes. Acceptable emmetropia was considered if the resulting spherical equivalent (SE) was within ±1.00 D. RESULTS: The majority of the studies used SRK/T formula (66.6%). The 88.9% of the reports obtained a SE within ±1.00 D. Using A-115 for ultrasound biometry and A-115.7 for optical biometry and SRK/T formula, the emmetropia (±1.00 D) of SE, was able to get near 100% of reported cases over the pupil implantation. However, the emmetropia decreased to 80% when the enclavation is retropupilar using the same formula. The A-constant can vary from 116.7 to 117.5 for retropupilar enclavation. CONCLUSIONS: Using A-115 for ultrasound biometry and A-115.7 for optical biometry and SRK/T formula, ±1.00 D of SE, is able to get near 100% of cases. Nevertheless, ±1.00 D of SE decreased to 80% of the cases when the enclavation is retropupilar.

Noninvasive Continuous Monitoring of Tear Glucose Using Glucose-Sensing Contact Lenses.

: The incidence of diabetes mellitus is dramatically increasing in the developed countries. Tight control of blood glucose concentration is crucial to diabetic patients to prevent microvascular complications. Self-monitoring of blood glucose is widely used for controlling blood glucose levels and usually performed by an invasive test using a portable glucometer. Many technologies have been developed over the past decades with the purpose of obtaining a continuous physiological glycemic monitoring. A contact lens is the ideal vehicle for continuous tear glucose monitoring of glucose concentration in tear film. There are several research groups that are working in the development of contact lenses with embedded biosensors for continuously and noninvasively monitoring tear glucose levels. Although numerous aspects must be improved, contact lens technology is one step closer to helping diabetic subjects better manage their condition, and these contact lenses will be able to measure the level of glucose in the wearer's tears and communicate the information to a mobile phone or computer. This article reviews studies on ocular glucose and its monitoring methods as well as the attempts to continuously monitor the concentration of tear glucose by using contact lens-based sensors.

Continuation of anticoagulant and antiplatelet therapy during phacoemulsification cataract surgery.

PURPOSE OF REVIEW: The objective of this review is to evaluate the result of cataract surgery in patients continuing antiplatelet and/or anticoagulant treatment. RECENT FINDINGS: The number of elderly patients using anticoagulant and antiplatelet treatment in prevention of venous thromboembolism has significantly increased in recent years. It was believed for many years that those patients might be at higher risk for complications during ocular surgery. Thus, different strategies were proposed to prevent these complications, including discontinuation of anticoagulants, dose reduction, or low-molecular-weight heparin replacement. We performed a PubMed search over a period of 7 years (2007-2013) about possible intraoperative and postoperative complications in patients receiving anticoagulant and/or antiplatelet therapy at the time of cataract surgery. No significant increase in intraoperative or postoperative complications has been identified. SUMMARY: Phacoemulsification of uncomplicated cataracts with intraocular lens implantation can be performed safely in high-risk patients, taking both anticoagulants and antiplatelet drugs when topical anesthesia is administered and cataract surgery is performed through a clear corneal incision by a skilled surgeon.

Development of a prediction formula of Parkinson disease severity by optical coherence tomography.

The aims of this study were to assess the peripapillary retinal nerve fiber layer (RNFL) thickness in patients with Parkinson's disease (PD), to determine its correlation with disease severity, and to define a simple biomarker for predicting clinical severity. One hundred two eyes from 52 patients affected by PD were compared with 97 eyes from 50 age-comparable controls. In all patients, peripapillary RNFL thickness was measured by optical coherence tomography (OCT). We used the Unified Parkinson's Disease Rating Scale (UPDRS) total score and measured responses in the on medication state. Eyes from patients with PD had a statistically significant decrease in average peripapillary RNFL thickness compared with control eyes (P < 0.001). This reduction was observed in every quadrant (inferior, superior, nasal [P < 0.001], and temporal [P = 0.017]) in patients with PD. Furthermore, a strong inverse correlation was found between the PD severity measured according to the UPDRS score and the average peripapillary RNFL thickness (r = -0.615; P < 0.001) and PD duration (r = -0.303; P = 0.002). From these results, we defined a regression equation that predicts the UPDRS score from the above-mentioned variables: UPDRS = 81.6 + 29.6 * log PD duration (years) - 0.6 * RFNL thickness (µm). We observed that, as the evolution and severity of PD progress, the peripapillary RNFL layer thickness, as evaluated by OCT, gradually diminishes. These results suggest that the average peripapillary RNFL thickness measured by OCT might be useful as a biomarker to detect the early onset and progression of PD.

Branch retinal vein occlusion and vitreovascular traction: a preliminary spectral domain OCT case-control study.

OBJECTIVE: Branch retinal vein occlusion (BRVO) typically occurs at an arteriovenous (AV) crossing site. Although the pathogenesis is unclear, vitreovascular traction might have a significant role in some BRVO cases. The purpose of present study was to determine the incidence of vitreoretinal traction at the obstruction site in patients diagnosed with BRVO. METHODS: In this prospective observational case­control study, 32 consecutive BRVO patients were studied with spectral-domain optical coherence tomography (SD-OCT) to detect the presence of vitreovascular traction or vitreous adherence at the occlusion site. RESULTS: SD-OCT directed to the occlusion site revealed a vitreovascular traction at this point in eight eyes (25 %). Fourteen eyes (43.75 %) were associated with an adherence of posterior hyaloids without signs of retinal traction, whereas ten eyes (31.25 %) had neither vitreoretinal adherence nor vitreous traction. Regarding either the same vessel segment of the fellow eye, none of the cases revealed vitreovascular traction in the correspondent AV crossing site; 12 cases (37.5 %) presented vitreoretinal adherence; and the remaining 20 cases (62.5 %) showed neither traction nor adhesion. Thus, vitreovascular traction in the occlusion site was significantly associated with BRVO (p = 0.024, chi-squared test). B-scan ultrasonography showed that the posterior vitreous cortex remains more frequently attached in eyes with BRVO compared to unaffected fellow eyes (p = 0.041, chi-squared test). CONCLUSIONS: A common firm vitreous adhesion at the obstruction site is reported herein, pointing out the possible role of vitreovascular traction in the etiology of some cases of BRVO. Likewise, although not all BRVO cases can be explained by this pathogenic mechanism, an attached posterior vitreous cortex might be a cofactor in the origin of this entity.

Age-related macular degeneration in the aspect of chronic low-grade inflammation (pathophysiological parainflammation).

The products of oxidative stress trigger chronic low-grade inflammation (pathophysiological parainflammation) process in AMD patients. In early AMD, soft drusen contain many mediators of chronic low-grade inflammation such as C-reactive protein, adducts of the carboxyethylpyrrole protein, immunoglobulins, and acute phase molecules, as well as the complement-related proteins C3a, C5a, C5, C5b-9, CFH, CD35, and CD46. The complement system, mainly alternative pathway, mediates chronic autologous pathophysiological parainflammation in dry and exudative AMD, especially in the Y402H gene polymorphism, which causes hypofunction/lack of the protective complement factor H (CFH) and facilitates chronic inflammation mediated by C-reactive protein (CRP). Microglial activation induces photoreceptor cells injury and leads to the development of dry AMD. Many autoantibodies (antibodies against alpha beta crystallin, alpha-actinin, amyloid, C1q, chondroitin, collagen I, collagen III, collagen IV, elastin, fibronectin, heparan sulfate, histone H2A, histone H2B, hyaluronic acid, laminin, proteoglycan, vimentin, vitronectin, and aldolase C and pyruvate kinase M2) and overexpression of Fcc receptors play role in immune-mediated inflammation in AMD patients and in animal model. Macrophages infiltration of retinal/choroidal interface acts as protective factor in early AMD (M2 phenotype macrophages); however it acts as proinflammatory and proangiogenic factor in advanced AMD (M1 and M2 phenotype macrophages).

The role of inflammation in the pathogenesis of macular edema secondary to retinal vascular diseases.

Macular edema (ME) is a nonspecific sign of numerous retinal vascular diseases. This paper is an updated overview about the role of inflammatory processes in the genesis of both diabetic macular edema (DME) and ME secondary to retinal vein occlusion (RVO). We focus on the inflammatory mediators implicated, the effect of the different intravitreal therapies, the recruitment of leukocytes mediated by adhesion molecules, and the role of retinal Müller glial (RMG) cells.

New MT-ND1 pathologic mutation for Leber hereditary optic neuropathy.

BACKGROUND: Mutations causing Leber hereditary optic neuropathy are usually homoplasmic, show incomplete penetrance, and many of the affected positions are not well conserved through evolution. A large percentage of patients harbouring these mutations have no family history of disease. Moreover, the transfer of the mutation in the cybrid model is frequently not accompanied by the transfer of the cellular, biochemical and molecular phenotype. All these features make difficult their classification as the etiologic factors for this disease. We report a patient who exhibits typical clinical features of Leber hereditary optic neuropathy but lacks all three of the most common mitochondrial DNA mutations. METHODS: The diagnosis was made based on clinical studies. The mitochondrial DNA was completely sequenced, and the candidate mutation was analysed in more than 18 000 individuals around the world, its conservation index was estimated in more than 3100 species from protists to mammals, its position was modelled in the crystal structure of a bacteria ortholog subunit, and its functional consequences were studied in a cybrid model. RESULTS: Genetic analysis revealed an m.3472T>C transition in the MT-ND1 gene that changes a phenylalanine to leucine at position 56. Bioinformatics, molecular-genetic analysis and functional studies suggest that this transition is the etiological factor for the disorder. CONCLUSIONS: This mutation expands the spectrum of deleterious changes in mitochondrial DNA-encoded complex I polypeptides associated with this pathology and highlights the difficulties in assigning pathogenicity to new homoplasmic mutations that show incomplete penetrance in sporadic Leber hereditary optic neuropathy patients.

Retinal and optic nerve evaluation by optical coherence tomography in adults with obstructive sleep apnea-hypopnea syndrome (OSAHS).

OBJECTIVE: To assess the peripapillary retinal nerve fiber layer (RNFL) thickness, optic nerve head (ONH) morphologic parameters, and macular thickness and volume in patients affected by obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: This prospective, observational case-control study consisted of 96 eyes of 50 OSAHS patients (mean age of 50.9 ± 12.4 years, best-corrected visual acuity ≥ 20/20, refractive error less than 3 spherocylindrical diopters, and intraocular pressure <21 mmHg) who were enrolled and compared with 64 eyes of 33 age-matched controls. Peripapillary RNFL thickness, ONH parameters, macular thickness and volume were measured by optical coherence tomography (OCT). RESULTS: OSAHS patients showed a significant reduction of the nasal quadrant RNFL thickness (74.7 ± 15.8 µm) compared with those values observed in control patients (81.1 ± 16.6 µm, p=0.047, Student's t-test). No differences in peripapillary RNFL thickness were observed when dividing the OSAHS group in accordance with disease severity. Vertical integrated rim area (VIRA) (0.67 ± 0.41 mm(3) in OSAHS vs 0.55 ± 0.29 mm(3) in controls; p=0.043, Student's t-test), horizontal integrated rim width (HIRW) (1.87 ± 0.31 mm(2) in OSAHS vs 1.8 ± 0.25 mm(2) in controls; p=0.039, Student's t-test) and disc area (2.74 ± 0.62 mm(2) in OSAHS vs 2.48 ± 0.42 mm(2) in controls; p=0.002, Student's t-test) showed significant differences, all of them being higher in the OSAHS group. Severe OSAHS had significant higher disc area (2.8 ± 0.7 mm(2)) than controls (2.5 ± 0.4 mm(2); p=0.016, ANOVA test). Temporal inner macular thickness was significantly higher in mild-moderate OSAHS patients (270 ± 12 µm) than in severe OSAHS patients (260 ± 19 µm; p=0.021, ANOVA test). CONCLUSIONS: OSAHS patients showed decreased peripapillary nasal RNFL thickness, and increased ONH area and volume parameters when they were evaluated by OCT. These findings suggest that neuronal degeneration might be present in the retina of OSAHS patients, as previously observed in some neurodegenerative disorders.

Ocular surface frostbite secondary to ethyl chloride spray.

CONTEXT: Ethyl chloride (EC) is a fast-acting vapo-coolant spray that provides rapid, transient, local analgesia for minor invasive procedures. Although the application of EC has decreased, it can be used as a cryoanalgesic agent in minor surgical procedures. OBJECTIVE: Despite the widespread use of EC as a local anesthetic, there are few reported cases of serious adverse side effects. MATERIAL AND METHODS: We report a 67-year old otherwise healthy man who underwent excision of a papilloma on his superior right eyelid by a general practitioner at a primary care center. The lesion was removed by curettage after slight freezing with EC spray. This chemical agent was applied without the adequate eye protection, and eight hours later the patient presented an acute frost injury of ocular surface. RESULTS: Urgent treatment included copious irrigation of the affected eye, especially the conjunctival fornices, corticosteroid (prednisone) and antibiotic (neomycin) ointment. A week later, the eyelid lesion and keratoconjunctivitis had resolved but evidence of early cicatrization involving the inferior conjucntival fornix and symblepharon formation were present. DISCUSSION: To the best of our knowledge, this is the first reported case of an acute burn of the ocular surface following EC spray exposure. CONCLUSION: EC should be avoided for short-term local anesthesia in the periocular region to prevent this serious complication.

Unilateral tacrolimus-associated optic neuropathy after liver transplantation.

BACKGROUND: Tacrolimus has been associated with several ocular adverse effects, such as optic neuropathy. METHODOLOGY/PRINCIPAL FINDINGS: A 56-year-old woman noted sudden, severe, painless visual loss in her left eye. She had undergone liver transplantation for alcoholic related cirrhosis 6 months before. Her chronic immunosuppressive regimen consisted of prednisone and tacrolimus at dosage of 1.5 mg orally once daily. Consequently, the patient developed a left optic neuropathy. CONCLUSION/SIGNIFICANCE: We report the first case of unilateral optic neuropathy associated with oral tacrolimus medication. Surgeons and ophthalmologists must evaluate ocular symptoms in the post-transplantation period, and suspicion should be maintained even if unilaterality or asymmetry of symptoms against a toxic etiology.

José Morón was the first to introduce the retinal light photocoagulation.

Regarding the early history of laser, it is generally accepted that the technique of retinal light photocoagulation was first pioneered by Gerd Meyer-Schwickerath in 1949. The renowned German ophthalmologist developed the technique to obtain clinically useful results and is worldwide considered the father of retinal photocoagulation. Nevertheless, we believe that the Spanish ophthalmologist José Morón (Seville, 1918-2000) was really the author of the first known experience of therapeutic photocoagulation of the retina, because he had previously used a similar technique in rabbit and human eyes in 1945 and 1946, respectively. These experiences already appeared in his doctoral dissertation, which was defended in Madrid in 1946, almost three years before the pioneering presentation of Meyer-Schwickerath. Despite this, Morón was permanently forgotten in the history of retinal photocoagulation. We would like to highlight his earlier experimental studies and reclaim the figure of this Spanish ophthalmologist, which deserves international recognition. This case is an example of a common phenomenon that inventors of new ideas are often not cited appropriately.

Long-Term Follow-Up of Macular Perfusion Evaluated by Optical Coherence Tomography Angiography after Rhegmatogenous Retinal Detachment Surgery.

BACKGROUND: The goal of this study was to investigate macular microvascular changes using optical coherence tomography angiography (OCTA) at one year after successful rhegmatogenous retinal detachment (RRD) surgery. METHODS: We performed a cross-section study including RRD treated by pars plana vitrectomy (PPV) with or without scleral buckling and SF6 tamponade. After 12 months, DRI-Triton SS-OCTA was performed. Superficial and deep retinal capillary plexuses (SCP and DCP), choriocapillaris (CC) vessel density (VD), and foveal avascular zone (FAZ) morphology were analyzed. Results were compared with the unaffected contralateral eye. RESULTS: Sixty eyes were included. We observed an increase in VD in the central area of both the SCP and DCP in macula-off eyes treated with PPV + SB and in the SCP of macula-off eyes treated with PPV. Macula-off eyes had a diminished VD for both plexuses in the superior quadrant and in the SCP inferior quadrant in those treated with PPV + SB. The CC flow was diminished in the temporal quadrant of macular-off eyes treated with PPV + SB. Healthy eyes presented higher diameter values than macula-off eyes treated with PPV + SB. FAZ horizontal and vertical diameters were smaller in patients with macula-off RRD vs. macula-on RRD and control groups. CONCLUSION: Macular vascularity remains almost unchanged one year after successful RRD surgery, irrespective of the surgical technique or prior macular status.

Assessment of the Effectiveness of Obstructive Sleep Apnea Treatment Using Optical Coherence Tomography to Evaluate Retinal Findings.

Retinal findings may change in patients with obstructive sleep apnea syndrome (OSAS). The present study aims to evaluate several retinal findings, such as macula layer thickness, the peripapillary retinal nerve fiber layer, and the optic nerve head in patients with OSAS, using optical coherence tomography (OCT); it also aims to monitor the result of several types of treatment of OSAS with OCT. A prospective comparative study was designed. Patients were recruited at a Sleep Unit of a University Hospital and underwent comprehensive ophthalmological examinations. Following exclusion criteria, fifty-two patients with OSAS were finally included. Patients were examined by OCT twice: once before treatment, and again after six months of treatment. In mild-moderate patients, where retinal swelling had been demonstrated, retinal thicknesses decreased [fovea (p = 0.026), as did inner ring macula (p = 0.007), outer ring macula (p = 0.015), and macular volume (p = 0.015)]. In severe patients, where retinal atrophy had been observed, retinal thickness increased [fovea (p < 0.001)]. No statistically significant differences in efficacy between treatments were demonstrated. In conclusion, OCT can evaluate the retina in patients with OSAS and help to monitor results after treatment. In severe OSAS, retinal thickness increased six months after treatment.

The role of retinal fluid location in atrophy and fibrosis evolution of patients with neovascular age-related macular degeneration long-term treated in real world.

PURPOSE: To assess the effect of clinical factors on the development and progression of atrophy and fibrosis in patients with neovascular age-related macular degeneration (nAMD) receiving long-term treatment in the real world. METHODS: An ambispective 36-month multicentre study, involving 359 nAMD patients from 17 Spanish hospitals treated according to the Spanish Vitreoretinal Society guidelines, was designed. The influence of demographic and clinical factors, including the presence and location of retinal fluid, on best-corrected visual acuity (BCVA) and progression to atrophy and/or fibrosis were analysed. RESULTS: After 36 months of follow-up and an average of 13.8 anti-VEGF intravitreal injections, the average BCVA gain was +1.5 letters, and atrophy and/or fibrosis were present in 54.8% of nAMD patients (OR = 8.54, 95% CI = 5.85-12.47, compared to baseline). Atrophy was associated with basal intraretinal fluid (IRF) (OR = 1.87, 95% CI = 1.09-3.20), whereas basal subretinal fluid (SRF) was associated with a lower rate of atrophy (OR = 0.40, 95% CI = 0.23-0.71) and its progression (OR = 0.44, 95% CI = 0.26-0.75), leading to a slow progression rate (OR = 0.34, 95% CI = 0.14-0.83). Fibrosis development and progression were related to IRF at any visit (p < 0.001). In contrast, 36-month SRF was related to a lower rate of fibrosis (OR = 0.49, 95% CI = 0.29-0.81) and its progression (OR = 0.50, 95% CI = 0.31-0.81). CONCLUSION: Atrophy and/or fibrosis were present in 1 of 2 nAMD patients treated for 3 years. Both, especially fibrosis, lead to vision loss. Subretinal fluid (SRF) was associated with good visual outcomes and lower rates of atrophy and fibrosis, whereas IRF yields worse visual results and a higher risk of atrophy and especially fibrosis in routine clinical practice.

Clinical characteristics of full thickness macular holes that closed without surgery.

PURPOSE: To ascertain the anatomic factors that help achieve non-surgical sealing in full thickness macular hole (FTMH). METHODS: Retrospective collaborative study of FTMH that closed without surgical intervention. RESULTS: A total of 78 patients (mean age 57.9 years) included 18 patients with blunt ocular trauma, 18 patients that received topical or intravitreal therapies and 42 patients with idiopathic FTMH. Mean±SD of the initial corrected visual acuity (VA) in logMAR improved from 0.65±0.54 to 0.34±0.45 (p<0.001) at a mean follow-up of 33.8±37.1 months. FTMH reopened in seven eyes (9.0%) after a mean of 8.6 months. Vitreomacular traction was noted in 12 eyes (15.8%), perifoveal posterior vitreous detachment in 42 (53.8%), foveal epiretinal membrane in 10 (12.8%), cystoid macular oedema (CME) in 49 (62.8%) and subretinal fluid (SRF) in 20 (25.6%). By multivariate analysis, initial VA correlated to the height (p<0.001) and narrowest diameter of the hole (p<0.001) while final VA correlated to the basal diameter (p<0.001). Time for closure of FTMH (median 2.8 months) correlated to the narrowest diameter (p<0.001) and the presence of SRF (p=0.001). Mean time for closure (in months) was 1.6 for eyes with trauma, 4.3 for eyes without trauma but with therapy for CME, 4.4 for eyes without trauma and without therapy in less than 200 µm in size and 24.7 for more than 200 µm. CONCLUSION: Our data suggest an observation period in new onset FTMH for non-surgical closure, in the setting of trauma, treatment of CME and size <200 µm.