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Vitreomacular traction (VMT) syndrome has only been surgically treated for a long time. Recently,enzymatic vitreolysis with ocriplasmin has emerged as a possible option to release VMT and, in some cases, close full thickness macular holes (FTMHs). Despite its clinical relevance, gathering information about the ocriplasmin-induced alterations of the Inner Limiting Membrane (ILM) of the retina in a clinical study is a complex task, mainly because of the inter-individual variability among patients. To obtain more insights into the mechanism underlying the drug action, we studied in-vitro the mechanical and morphological changes of the ILM using Atomic Force Microscopy (AFM). To this aim, we measured the ILM average Young’s modulus (YM), hysteresis (H) and adhesion work (A) over time under ocriplasmin treatment. Our data unveil a time-dependent increase in the 34 membrane YM of 19% of its initial value, along with changes in its adhesive and dissipative behavior. Such modifications well correlate with the morphological alterations detected in the AFM imaging mode. Taken all together, the results here presented provide more insights into the mechanism underlying the ocriplasmin action in-vivo, suggesting that it is only able to alter the top-most layer of the vitreal side of the membrane, not compromising the inner ILM structure.

PURPOSE: Recent studies show that patients with Usher syndrome type 2 (USH2) have abnormal cone structure and density in the central retina. This occurs in the presence of normal acuity, opening the quest for additional sensitive functional measures of central cone function in USH. We tested here whether focal macular cone electroretinogram (fERG) could be such a tool. METHODS: This retrospective study of central cone function loss was based on data from 47 patients with USH2 from the Ophthalmology Department of the Policlinico Gemelli/Catholic University in Rome. The analysis focused on the decrease of the fERG, obtained in response to a 41-Hz sinusoidal modulation of a uniform field presented to the central 18°, generated by red light-emitting diodes (LEDs) and superimposed on an equiluminant steady adapting background. fERG decrease was compared with the decrease of best-corrected visual acuity and Goldmann kinetic perimetry V4E field. RESULTS: fERG follow-up data document a severe and precocious loss of central cone function in USH2 patients, preceding losses in other measures of cone function. fERG is already reduced to 40% of control at the beginning of the second decade of life, and by 25 years of age, all USH2 patients have fERGs less than 30% of control values. CONCLUSIONS: fERG represents a sensitive tool to evaluate central cone function in USH2, anticipating the decline of other central cone function measures, such as visual acuity and Goldmann perimetry.

PURPOSE. Recent studies show that patients with Usher syndrome type 2 (USH2) have abnormal cone structure and density in the central retina. This occurs in the presence of normal acuity, opening the quest for additional sensitive functional measures of central cone function in USH. We tested here whether focal macular cone electroretinogram (fERG) could be such a tool. METHODS. This retrospective study of central cone function loss was based on data from 47 patients with USH2 from the Ophthalmology Department of the Policlinico Gemelli/Catholic University in Rome. The analysis focused on the decrease of the fERG, obtained in response to a 41-Hz sinusoidal modulation of a uniform field presented to the central 18°, generated by red light-emitting diodes (LEDs) and superimposed on an equiluminant steady adapting background. fERG decrease was compared with the decrease of best-corrected visual acuity and Goldmann kinetic perimetry V4E field. RESULTS. fERG follow-up data document a severe and precocious loss of central cone function in USH2 patients, preceding losses in other measures of cone function. fERG is already reduced to 40% of control at the beginning of the second decade of life, and by 25 years of age, all USH2 patients have fERGs less than 30% of control values. CONCLUSIONS. fERG represents a sensitive tool to evaluate central cone function in USH2, anticipating the decline of other central cone function measures, such as visual acuity and Goldmann perimetry.

Age-related macular degeneration (AMD) is a complex multifactorial disease and the primary cause of legal and irreversible blindness among individuals aged ≥65 years in developed countries. Globally, it affects 30−50 million individuals, with an estimated increase of approximately 200 million by 2020 and approximately 300 million by 2040. Currently, the neovascular form may be able to be treated with the use of anti-VEGF drugs, while no effective treatments are available for the dry form. Many studies, such as the randomized controlled trials (RCTs) Age-Related Eye Disease Study (AREDS) and AREDS 2, have shown a potential role of micronutrient supplementation in lowering the risk of progression of the early stages of AMD. Recently, low-grade inflammation, sustained by dysbiosis and a leaky gut, has been shown to contribute to the development of AMD. Given the ascertained influence of the gut microbiota in systemic low-grade inflammation and its potential modulation by macro- and micro-nutrients, a potential role of diet in AMD has been proposed. This review discusses the role of the gut microbiota in the development of AMD. Using PubMed, Web of Science and Scopus, we searched for recent scientific evidence discussing the impact of dietary habits (high-fat and high-glucose or -fructose diets), micronutrients (vitamins C, E, and D, zinc, beta-carotene, lutein and zeaxanthin) and omega-3 fatty acids on the modulation of the gut microbiota and their relationship with AMD risk and progression.

PURPOSE: Recent studies show that patients with Usher syndrome type 2 (USH2) have abnormal cone structure and density in the central retina. This occurs in the presence of normal acuity, opening the quest for additional sensitive functional measures of central cone function in USH. We tested here whether focal macular cone electroretinogram (fERG) could be such a tool. METHODS: This retrospective study of central cone function loss was based on data from 47 patients with USH2 from the Ophthalmology Department of the Policlinico Gemelli/Catholic University in Rome. The analysis focused on the decrease of the fERG, obtained in response to a 41-Hz sinusoidal modulation of a uniform field presented to the central 18°, generated by red light-emitting diodes (LEDs) and superimposed on an equiluminant steady adapting background. fERG decrease was compared with the decrease of best-corrected visual acuity and Goldmann kinetic perimetry V4E field. RESULTS: fERG follow-up data document a severe and precocious loss of central cone function in USH2 patients, preceding losses in other measures of cone function. fERG is already reduced to 40% of control at the beginning of the second decade of life, and by 25 years of age, all USH2 patients have fERGs less than 30% of control values. CONCLUSIONS: fERG represents a sensitive tool to evaluate central cone function in USH2, anticipating the decline of other central cone function measures, such as visual acuity and Goldmann perimetry.

BACKGROUND: To study the photopic negative response of the full-field photopic ERG in Stargardt patients with pathogenic variants in the ABCA4 gene. METHODS: A retrospective analysis of 35 Stargardt patients with ABCA4 gene pathogenic variants, compared to normal age matched controls. Patients were clinically followed at the Ophthalmology Department of Fondazione Policlinico Universitario A. Gemelli/Università Cattolica del Sacro Cuore - Rome, Italy. RESULTS: The photopic negative response of the full-field photopic ERG was compromised in most Stargardt patients. In the presence of a normal B-wave, the amplitude ratio between the photopic negative response and the B-wave displayed a 97% accuracy in detecting diseased eyes (ROC curves). CONCLUSIONS: In Stargardt patients with ABCA4 pathogenic mutations, the photopic negative response of the full-field photopic ERG is a very sensitive disease read-out. Its inclusion in standard ERG analysis would be a no-cost addition of practical consequence in the follow-up of Stargardt disease. The early impairment of the photopic negative response suggests that inner retinal function might be affected in Stargardt disease earlier than previously acknowledged.

Purpose: To assess short-term changes in macular function after transpupillary thermotherapy (TTT) in patients with occult subfoveal choroidal neovascularization (CNV) secondary to agerelated macular degeneration (AMD), using focal electroretinography (FERG). Methods: Twenty-five patients with occult subfoveal CNV due to AMD were treated with TTT delivered using an infrared (810 nm) diode laser (spot size 3.0 mm, laser power 400-600 mW, duration 60 seconds). All patients were clinically evaluated before, 1 and 6 weeks after treatment. Snellen visual acuity (VA) was measured at each visit. Fluorescein angiography (FA) was performed at baseline and 6 weeks after TTT. Focal ERGs were recorded in all patients immediately before and 1 week after TTT in response to an 18-degree diameter, 41 Hz flickering spot (630 nm) centred on the fovea, presented on a steady background in Maxwellian view. A subgroup of 12 patients was also re-tested by FERG at 6-weeks post-TTT. Results: No significant changes in mean FERG amplitude and phase were observed across the different recording sessions before and after TTT. One week after TTT, four patients had significant (>2 SD from baseline variability) increases in FERG amplitude and/or phase advances, one had a decrease in amplitude and four had phase delays, compared to baseline. The remaining 15 patients had stable FERGs. Six weeks after TTT, four patients had significant increases in FERG amplitude and/or phase advances, four had decreases in amplitude and/or phase delays, and four had stable FERGs, compared to baseline. Improvement in FERG parameters after TTT was always associated with an improvement in VA and a decrease in exudation. Patients with post-TTT FERG deterioration had stable or deteriorated clinical pictures. At either 1 or 6 weeks post-TTT, the FERG amplitude increase was inverselycorrelated (p < 0.05) with the baseline FERG amplitude and VA. Conclusions: Three major conclusions can be drawn: in a short-term follow

Purpose. The aim of this study was to evaluate the function of the neurosensory retina in Best vitelliform macular dystrophy (BMD) by recording the focal electroretinogram (FERG) fundamental and 2nd harmonic components, which are known to be dominated by receptoral and postreceptoral activity, respectively. Methods. FERGs were recorded in response to a uniform field (9 x 9 deg) flickered sinusoidally at either 8 Hz or 32 Hz (peak frequencies for the 2nd and fundamental harmonic, respectively). The fundamental component of the response to the 32-Hz stimulus and the 2nd harmonic of the response to the 8-Hz stimulus were measured in their amplitudes and phases. The fundamental-2nd harmonic amplitude ratio was taken as an index of the relative changes in the FERG components. Eleven patients with BMD and vitelliform stage macular lesions were evaluated. Results were compared with those obtained from 13 patients with Type 2 Stargardt macular dystrophy (STD) according to the Noble and Carr classification, and 29 normal control subjects. Four BMD and four STD patients were also followed electrophysiologically over a 48 month period. Results. Compared to controls, BMD patients showed losses of both FERG fundamental and 2nd harmonic amplitudes, and an increase in the fundamental-2nd harmonic ratio. STD patients also showed losses of both fundamental and 2nd harmonic, but the fundamental-2nd harmonic ratio was normal. In BMD patients, but not in those with STD, the fundamental amplitude tended to decrease over the follow-up period. Conclusions. The results indicate that BMD involves neurosensory abnormalities early in the disease process. The increased fundamental-2nd harmonic ratio suggests that a postreceptoral dysfunction may be present in addition to that of photoreceptors. This differs from STD, where losses appear to affect primarily the receptoral retina. Receptoral losses in BMD may progress throughout the medium-term follow-up.

The Authors report a case of Terson's syndrome, surgically treated by vitrectomy via pars plana and discuss the etiopathogenetic features as well as the clinicopathologic aspects and the management of this syndrome.

Ophthalmological consultation in patients suffering from haematological diseases (neoplastic or not) is very important, as ocular involvement in hemopoietics disorders is frequent and often typical. Moreover, ocular changes are caused by different types of pharmacological and/or radiant therapy. The Authors consider ocular changes in haematological diseases and discuss ocular complications of antineoplastic treatment

Pneumoretinopexy, associated with laser photocoagulation, is a new technique for non-surgical treatment of reghmatogenous retinal detachment with retinal tears located superiorly or in the macular area. The Authors report three cases of patients treated with a new technique of pneumoretinopexy and oculorotation, which allows to treat also retinal detachments with retinal tears in the inferior quadrants

Tuberous sclerosis is a rare clinical entity, commonly considered as a phakomatosis, characterized by multiple tumors (hamartomas) of the brain, skin, eye and many organs as kidney, heart, spleen and•lung. It is inherited in an irregular authosomal dominant fashion. Ocular findings are multiple retinal astrocytic hamartomas and more rarely non retinal fibrous tumors. Authors consider clinical and diagnostic features of tuberous sclerosis and describe a case of vitreous hemorrhage complicating retinal astrocytic hamartomas

Steady-state macular (9° × 9°) electroretinograms in response to either sinusoidal flicker (focal electroretinogram) or counterphased sinusoidal gratings (pattern electroretinogram) were recorded in 14 patients with inner lamellar macular holes, in 4 patients with full-thickness macular holes and in 14 age-matched controls. Fourier analysis of focal and pattern electroretinograms yielded three main components: a first and a second harmonic to flicker, and a second harmonic to pattern. Recent evidence indicates that the first harmonic to flicker is of receptoral origin, whereas the flicker and pattern second harmonics represent, at least in part, the activity of different generators in the inner retina. When compared to controls, patients with inner lamellar holes showed significant amplitude reduction and phase delay for both flicker and pattern second harmonics, but not for the flicker first harmonic. Patients with full-thickness holes showed significant amplitude reduction also for the flicker first harmonic. These results indicate a prevalent functional involvement of the inner retina in lamellar macular holes, which can be clinically detected by evaluating focal and pattern electroretinogram second harmonics. © 1992 Kluwer Academic Publishers.

The authors discuss the clinical and histopathologic findings of macular holes, explaining the classification, the clinical features and the differential diagnosis. This could encourage a better knowledge of the ethiologic and prognostic factors of the macular holes, that remaining not well known yet

Laser photocoagulation in the treatment of diabetic retinopathy classified into non-proliferative, preproliferative and proliferative forms is reviewed. Clinical aspects and pathophysiological mechanisms are examined to explain the rationale of laser photocoagulation. Focal and grid techniques are described for macular edema in non-proliferative retinopathy giving treatment parameters and wavelength characteristics. PRP (panretinal photocoagulation) is described for proliferative diabetic retinopathy. Results and present trends are reported with indications and complications. Endophotocoagulation is then described as the technique utilized during pars plana vitrectomy in advanced diabetic retinopathy

The Authors describe the clinical features of choroidal metastasis, the most common in traocular malignancies, and discuss the clinical and differential-diagnostic aspects as well as the management and the therapy.

OBJECTIVE - Psychophysical methods in patients with diabetes mellitus reveal deficits of central or foveal vision. Our aim was to evaluate the contrast-sensitivity thresholds in 24 insulin-dependent (type I) diabetic patients with a short disease duration and without retinopathy, taking into account metabolic control. RESEARCH DESIGN AND METHODS - The control group consisted of age-matched nondiabetic subjects. None had visual or systemic symptoms. Contrast sensitivity measured at eight different spatial frequencies to sinusoidal bar patterns of 0.6-12.2 cycles/deg can detect functional defects in the spatially sensitive retinal ganglion cells or in higher visual pathways. We performed two different temporal types of contrast-sensitivity testing, dynamic (8 Hz) and static (0 Hz). RESULTS - Significant losses with dynamic contrast-sensitivity test at all but the highest spatial frequencies (i.e., 12.2 cycles/deg) were shown, whereas there was significant attenuation of contrast sensitivity at five spatial frequencies (1.0, 1.4, 2.2, 7.1, and 9.6 cycles/deg) in the static mode. Grating losses (<2SD of control means) of contrast sensitivity were found in 33.3% (dynamic) and in 72.9% (static) of eyes of diabetic patients. HbA(1c) values were positively correlated at variable spatial frequencies (1.0, 1.4, and 2.2 cycles/deg for dynamic test and 0.6, 1.0, 1.4, 2.2, 4.8, and 7.1 cycles/deg for static test). CONCLUSIONS - Our results suggest an early, generally nonselective neuronal damage of visual pathways that occurs before the onset of clinically detectable retinopathy. The visual deficit may be related directly to the effects of diabetes; repetitive minor hypoglycemic insults may contribute more than a marked hyperglycemic condition to the mechanisms underlying physiological changes along the optic nerve.

The Authors after describing diagnostic problems regarding "angioid streaks retinopathy" evaluate the natural history of the disease and its complications

We report our experience with treatment of Cytomegalovirus (CMV) retinitis in AIDS patients; intravenous and/or intravitreal ganciclovir therapy seems to be quite safe and effective

The Authors describe the clinical and histopathologic features Of choroidal osteoma, a uncommon benign intraocular neoplasm, and discuss the clinical and differential-diagnostic aspects

Steady-state pattern electroretinogram (PERG) in response to sinusoidal gratings (1.7 c/deg spatial frequency; 9 × 9 deg field size) temporally modulated (sinusoidally) at 8 Hz were recorded in 40 insulin-dependent diabetics and 28 age-matched normal subjects. Visual acuity was ≥ 20/20 in all 40 patients; 31 (62 eyes) showed no sign of retinopathy and nine (18 eyes) showed a few microaneurysms on fluorescein angiography. Insulin-dependent diabetics showed a significant reduction in the PERG mean amplitude as compared with age-matched control subjects (one-way analysis of variance: p < 0.0001). Significant differences were observed between normals and diabetics without retinopathy (Scheffé test: p < 0.0001), normals and diabetics with early retinopathy (Scheffé test: p < 0.0001), no retinopathy and early retinopathy patients (Scheffé test: p < 0.05). In diabetics without retinopathy multi-factorial analysis of variance revealed a significant effect of age of onset of the disease (p < 0.01) and an interaction effect between age of onset and duration (p < 0.001) on PERG amplitude. These results suggest a possible use of the steady-state PERG to detect early macular dysfunction in insulin-dependent diabetics. © 1990 Kluwer Academic Publishers.

Experimental and clinical studies have demonstrated that the electroretinogram in response to periodical patterns alternating in contrast at constant mean luminance (pattern reversal ERG, P-ERG), is correlated with ganglion cell activity. Senile functional changes of these neurons might be therefore investigated by the P-ERG technique. Steady-state P-ERGs (8 Hz) in response to sinusoidal gratings of different spatial frequencies (0.6-6.8 c/d) were recorded in normal subjects ranging over 50 year age span. The P-ERG amplitude as a function of stimulus spatial frequency shows a maximum between 1.2-1.7 c/d and attenuation at higher and lower spatial frequencies (spatial tuning). The P-ERGs of the older subjects are reduced in amplitute, as compared to those of the younger ones, over the whole range of spatial frequency. This reduction is more marked at intermediate spatial frequencies resulting in a shallower tuning.