Dimitrios Alonistiotis

Evaluation of successful macular hole surgery by optical coherence tomography and multifocal electroretinography.

PURPOSE To evaluate successful macular hole surgery using optical coherence tomography (OCT) and multifocal electroretinography (MFERG). DESIGN Interventional case series. METHODS In a prospective study, 20 eyes of 20 patients with successful surgery for stage II, III, or IV idiopathic macular hole were evaluated by best-corrected visual acuity (BCVA), ocular examination, OCT, and MFERG preoperatively and 1, 3, 6, and 12 months postoperatively. For statistical analysis, the paired t test and nonparametric methods were used, as well as the Spearman analysis. RESULTS Postoperatively, all 20 eyes of 20 patients had anatomic closure of the macular hole confirmed by OCT. The center of the fovea, measured by OCT from the retinal pigment epithelium to the inner retinal surface, had a mean +/- SD thickness of 116.5 +/- 30.9 microm (range, 68-175 microm) 1 year postoperatively. Best-corrected visual acuity significantly improved (preoperative mean +/- standard deviation [SD] value, 0.131 +/- 0.081 and 1 year postoperative mean +/- SD value, 0.407 +/- 0.193). Multifocal electroretinography values area 1 (0-2.8 degrees) and area 2 (2.8-9 degrees from the center of the fovea) significantly improved (preoperative mean +/- SD values 3.10 +/- 1.334 nV/deg(2) and 3.573 +/- 1.545 nV/deg(2), respectively, and 1 year postoperative +/- SD mean values, 5.53 +/- 1.208 nV/deg(2) and 4.748 +/- 1.404 nV/deg(2), respectively). The thickness of the fovea, measured by OCT, significantly correlated with the BCVA 1 year postoperatively. One year postoperative MFERG values areas 1 and 2 were not correlated with 12-month BCVA and OCT findings. CONCLUSIONS Twelve months postoperatively BCVA and MFERG values significantly improved in this series of eyes with successful macular hole surgery. Optical coherence tomography findings were correlated to BCVA, but MFERG values were not correlated to BCVA and OCT findings, 1 year postoperatively.

Comparison of the nerve fiber layer of type 2 diabetic patients without glaucoma with normal subjects of the same age and sex.

Background The retinal nerve fiber layer (RNFL) thickness in patients with diabetes mellitus type 2 was compared to normal subjects of similar age and sex, having first excluded any risk factors for glaucoma. The correlation between the RNFL thickness and the severity of diabetic retinopathy was investigated at its primary stages and with other ocular and diabetic parameters. Methods A prospective, case series study was carried out. Twenty-seven diabetic patients without diabetic retinopathy, 24 diabetic patients with mild retinopathy, and 25 normal, age-matched subjects underwent a complete ophthalmological examination and imaging with scanning laser polarimetry for the evaluation of the RNFL. Multivariate analysis was applied in order to investigate the correlation between RNFL and diabetic parameters, such as age, duration of diabetes, insulin therapy, levels of glycosylated hemoglobin; and ocular parameters, such as cup to disc ratio, levels of normal intraocular pressure, and central corneal thickness. Results The mean inferior average of RNFL and the temporal-superior-nasal-inferior-temporal standard deviation were statistically significantly lower in both diabetic groups, and the nerve fiber index was higher (P=0.04) compared to the normal group. There was no statistically significant difference between the diabetic groups. The factor analysis showed no significant correlation between the RNFL and the previously mentioned diabetic and ocular parameters. Conclusion The existence of diabetes should be seriously considered in evaluating the results of scanning laser polarimetry. Multivariate analysis for RNFL was used for the first time.

Video-to-Video for e-Health: Use Case, Concepts and Pilot Plan

Future Internet and smart cities are creating a very promising paradigm for providing advanced services to citizens. The paradigm of e-Health forms a valuable yet demanding use case for design, develop, deploy and provide related services. The aim of LiveCity project is to empower the citizens of a city to interact with each other in a more productive efficient and socially useful way by using high quality video-to-video (v2v); v2v can be used to improve medical services. This paper presents the related concepts, the scenario and the pilot set for the tele-monitoring service realization, deployment and provision.

New optical coherence tomography fundus findings in a case of beta-thalassemia

Patients with beta-thalassemia may present with an acquired diffuse elastic tissue defect due to degeneration of elastic tissue along with vaso-occlusive findings in the retinal microvasculature. Here we report the case of a patient with granular-like accumulation presenting as black sunburst lesions detected by optical coherence tomography (OCT). A 38-year-old man with beta-thalassemia intermedia associated with angioid streaks complained of deterioration of vision in both eyes. Funduscopic examination revealed small, round, hyperpigmented lesions bilaterally. During the early and late phases of fluorescein angiography, granular hyperfluoresence was present, associated with pigment decompensation and mottled-like hypofluorescence. The main OCT finding was the presence of granuloid-like accumulations at the retinal pigment epithelium level. Granule penetration was also noticed at the photoreceptor layer, while isolated granuloid-like accumulations were found in the inner layers of the macula and choroid. In this case, the new OCT finding was the granular-like hyperpigmented accumulations in the macula located at the level of the retinal pigment epithelium. To the best of our knowledge, our OCT findings show for the first time granuloid-like accumulations representing black sunburst lesions.

Macular hole formation following phacoemulsification cataract surgery

Idiopathic full-thickness macular holes develop as a result of antero-posterior and tangential traction exerted by the posterior vitreous cortex at the fovea. Although full-thickness macular holes (FTMH) were originally described in the last century, in relation to trauma, inflammation and myopia, more recent clinical studies have shown that the vast majority is idiopathic. Macular holes are more common in women and have been classified in four stages: 1. Stage 1 is also termed an impending hole and is characterised by progressive loss of the foveal depression. The visual acuity at this stage is reasonably good. 2. When further traction results in the formation of a foveal hole or dehiscence associated with a cuff of subretinal fluid, the hole is characterised as stage 2 and the visual acuity usually deteriorates to a level of 6/12 to 6/30. 3. In stage 3, the macular hole is fully developed and there is no posterior vitreous detachment (PVD). Stage 3 holes are usually associated with acuity levels of 6/18 to 6/60. 4. When posterior vitreous detachment occurs the hole is characterised as stage 4. Macular hole as a complication of phacoemulsification is a rare entity. The implicated pathophysiology is not yet completely understood and it appears to be multifactorial. Here, we report two cases of macular hole formation following phacoemulsification, each one following a different path in the pathophysiological pathway.

Follow-up of the retinal nerve fiber layer thickness of diabetic patients type 2, as a predisposing factor for glaucoma compared to normal subjects

Purpose To evaluate and follow-up the retinal nerve fiber layer (RNFL) thickness in patients with diabetes mellitus type 2 compared to a group of healthy individuals with similar demographic characteristics. Patients and methods This is a prospective, noninvasive, observational case series study. For the purposes of the study, 27 eyes of diabetic patients without diabetic retinopathy, 24 eyes of patients with mild retinopathy, and 25 normal age-matched subjects (control group [CG]) were examined. All participants underwent complete ophthalmological examination and imaging with GDx variable corneal compensation scanning laser polarimetry. Follow-up was 2 years for all three groups. Results The mean inferior average was statistically significantly lower in both diabetic groups compared to CG at baseline examination and during follow-up. The nerve fiber indicator (NFI) was higher in both diabetic groups compared to CG, both at baseline examination and during follow-up. The NFI was 21.7±11.9 and 22.0±11.8 for the diabetic group without retinopathy, 20.8±9.6 and 21.9±9.8 for the group with mild retinopathy, and 15.3±5.4 and 15.9±5.5 for the normal subjects, at baseline and 24 months, respectively. There was no statistically significant reduction of the RNFL thickness in all three groups compared to baseline examination. Conclusion This is the first long-term study documenting the RNFL thickness in diabetic patients in comparison with normal controls. Although the lower RNFL was found thinner in diabetics, the 2-year follow-up showed no significant reduction of RNFL thickness in all groups, indicating that RNFL damage may occur early in diabetic patients.

Long-term anatomical and functional results in patients undergoing observation for idiopathic nontractional epiretinal membrane.

Purpose To evaluate the anatomical and functional course without surgical intervention in patients with nontractional epiretinal membrane (ERM) using spectral-domain optical coherence tomography (SD-OCT) in a long-term follow-up of 38.2 ± 30.6 months. Methods Participants were 58 patients with nontractional ERM, which was defined as a tear or rip of the ERM in at least one line of OCT scan. All patients were observed without any surgical intervention. All patients underwent ophthalmologic examination, including best-corrected visual acuity (BCVA) measurement, funduscopy, and SD-OCT. Routine follow-up visits were performed every 6 months or earlier at the discretion of the investigator. Results There was no statistically significant difference in BCVA or central foveal thickness (CFT) at all time points of the follow-up. About 84.4% of patients presented improvement or stabilization in BCVA at the end of the follow-up, while 53.4% of patients had a decrease in CFT. All patients had intact ellipsoid zone and none of them needed surgical intervention at the end of the follow-up of 38.2 ± 30.6 months. Conclusions In patients with nontractional ERM, BCVA and CFT may remain stable in a long-term follow-up. Therefore, if ellipsoid zone is intact and there is a tear or rip of ERM in at least one OCT scan, patients can be monitored and surgery may be deferred because of high percentage of structural and functional stability.

Remote Video-to-Video Eye Telemonitoring Use Case for Glaucoma Patients

Glaucoma is the second leading cause of blindness globally and the second most common cause of avoidable visual impairment. It also holds a record in noncompliance to therapy from the patients in up to 50% of the subjects treated with anti-glaucoma eye drops. LiveCity e-Health is a European research program, which aims to provide better treatment and follow up of glaucoma patients at their home, through telemonitoring with high definition video-to-video (v2v) communication from the University Hospital. Secondly, it aims to reduce the cost of health and improve the city environment by decreasing the number of visits to the Hospital. For this purpose, a software application has been developed; the latter is easy to use for elderly people at home, and capable of keeping the medical history and digital records of every patient in the Glaucoma Department. In addition, a specific web camera with snapshot ability of high quality photo of the eye has utilised. Two patients have been initially enrolled in the study and the preliminary results are so presented.