A Pathogenetic Classification of Diabetic Macular Edema.

PURPOSE: The aim of this study was to define a new pathogenetic classification of diabetic macular edema (DME) and to present the results of its application in common clinical practice. METHODS: One hundred and seventy-seven consecutive patients with center-involving DME, central retinal thickness (CRT) ≥250 µm, were prospectively enrolled. A complete ophthalmological examination included best-corrected visual acuity (BCVA) assessment, fundus photography, and spectral-domain optical coherence tomography (OCT). The DME classification was broken down into 4 categories, combining the presence of retinal thickening with the presence/absence of visible vascular dilations and OCT-detectable macular traction. The OCT parameters included were as follows: CRT, subretinal fluid, intraretinal cysts, and hyper- reflective foci (HF). RESULTS: Four subtypes of DME were identified: vasogenic (131 eyes, DME with vascular dilation), nonvasogenic (46 eyes, DME without vascular dilation), tractional (11 eyes), and mixed DME (13 eyes). Vasogenic DME was the pattern mainly represented in each subclass of CRT (< 300, 300-400, and > 400 µm), with tractional DME observed especially with CRT > 400 µm. Internal and external cysts and a greater presence of hard exudates were predominantly found in vasogenic DME, whereas HF was equally distributed in the 4 DME subgroups. CONCLUSION: The study offers a new pathogenetic classification able to detect significant differences among DME subtypes. A tailored therapeutic approach could take into consideration specific changes associated with the different DME subtypes.

Microperimetric assessment of the two optical coherence tomography subtypes of acute macular neuroretinopathy.

BACKGROUND: This study evaluates the morpho-functional alterations associated with acute macular neuroretinopathy (AMNR). DESIGN: Prospective observational case series study carried out at the University Vita-Salute, Scientific Institute San Raffaele. PARTICIPANTS: Five out of six eyes (three patients) showed the typical features of AMNR. METHODS: The patients underwent an ophthalmological examination, including best-corrected visual acuity (BCVA) measurement, electroretinogram and electroculogram (ERG/EOG), multifocal electroretinogram (mfERG), infrared reflectance, short wavelength and near-infrared-fundus autofluorescence (SW-FAF/NIR-FAF), spectral-domain optical coherence tomography (SD-OCT) and microperimetry. MAIN OUTCOME MEASURE: Microperimetric alterations in the two SD-OCT subtypes of AMNR. RESULTS: The BCVA was 20/20 in all patients. ERG and EOG were normal; mfERG revealed a generally reduced response with a more reduced signal in the areas corresponding to the macular lesions. SD-OCT demonstrated two different patterns of retinal alterations. In case 1, SD-OCT revealed a hyperreflective, plaque-like band at the junction of the outer plexiform layer (OPL) and the inner nuclear layer (INL), extending into the INL (type 1 lesion). In cases 2 and 3, SD-OCT disclosed a hyperreflectivity of the OPL associated with outer nuclear layer thinning and disruption of the outer segment/retinal pigment epithelium junction (type 2 lesion). Microperimetry revealed a wide scotoma involving the entire macular area in all eyes, including the unaffected eye of case 1. The reduction in retinal sensitivity was greatest in type 1. CONCLUSIONS: SD-OCT confirms that AMNR may occur in different patterns. Microperimetry demonstrated that functional alterations are also discernible in apparently uninvolved areas. Both examinations are extremely valuable in characterizing the changes associated with AMNR.

Intravitreal ranibizumab for pigment epithelium detachment with subfoveal occult choroidal neovascularization: a prospective 24-month case series.

PURPOSE: To assess the effects of intravitreal ranibizumab injection in patients affected by pigment epithelial detachment associated with occult subfoveal choroidal neovascularization. DESIGN: Prospective, interventional case series. PARTICIPANTS: Forty eyes of 40 patients were considered for the purpose of the study. Consecutive patients were recruited for a 24-month study. All patients underwent a complete ophthalmic examination, including best-corrected visual acuity on Early Treatment Diabetic Retinopathy Study (ETDRS) charts. After a 3-monthly loading phase, further intravitreal ranibizumab injections were administered on the basis of detection of any type of fluid on optical coherence tomography. PRIMARY OUTCOME MEASURES: Changes in mean best-corrected visual acuity at 12 and 24 months and the proportion of eyes losing fewer than 15 letters (corresponding to 3 ETDRS lines) from baseline visual acuity. SECONDARY OUTCOME MEASURES: Changes in central macular thickness on optical coherence tomography and variation in mean area of the entire lesion. RESULTS: Forty patients were included. Mean best-corrected visual acuity decreased from 20/66 (58 ETDRS letters) to 20/83 (53 letters) at 12 months and 20/112 (489 ETDRS letters) at 24 months (P = .003). Eighty percent and 67.5% of eyes lost fewer than 3 lines at 12 and 24 months, respectively. Mean central macular thickness passed from 545 µm to 428 µm at 12 months and 426 µm at 24 months. Mean lesion area changed from 6826 µm(2) to 6312 µm(2) at 12 months and 6010 µm(2) at 24 months. CONCLUSIONS: The treatment of pigment epithelial detachment associated with occult subfoveal choroidal neovascularization with intravitreal ranibizumab injection after a 3-monthly loading phase and pro re nata strategy can lead to partial results over a 24-month follow-up. Further investigations are warranted to establish the best therapeutic approach to this disease.

Rebound effect after intravitreal dexamethasone implant for the treatment of macular edema secondary to central retinal vein occlusion.

AIM: To report on the rebound macular edema (ME) effect following dexamethasone implant for the treatment of nonischemic central retinal vein occlusion (CRVO). METHODS: Twenty-one patients affected by ME secondary to central retinal vein occlusion (CRVO) underwent an implant of dexamethasone (700 µg) in a compassionate use program. The patients were followed up monthly. The Early Treatment Diabetic Retinopathy Study (ETDRS) best corrected visual acuity (BCVA), central retinal thickness (CRT) on optical coherence tomography (OCT), and intraocular pressure were registered at monthly intervals. Retreatments were carried out on a pro-re-nata (PRN) basis starting from the third month. RESULTS: Both BCVA and CRT improved in all cases. A rebound effect, characterized by a recurrence of ME in excess of the baseline value, occurred in 3 cases (13%) at months 3 and 4. Visual acuity accordingly dropped at the higher CRT values in the 3 cases displaying the rebound effect. Additional treatment with dexamethasone implant led to both a recovery in visual acuity and reduction in CRT. CONCLUSIONS: A rebound effect can occur after dexamethasone implant for the treatment of ME related to CRVO, but does not affect functional or anatomical recovery when retreatment is provided. The retreatment rate with dexamethasone implant should be adapted to suit the patient's response.

Intravitreal bevacizumab for subfoveal choroidal neovascularization associated with pattern dystrophy.

PURPOSE: To assess the effects of intravitreal bevacizumab injections in the treatment of subfoveal choroidal neovascularization (CNV) associated with pattern dystrophy (PD) of the retinal pigment epithelium. METHODS: The study was a prospective, nonrandomized, open-label, interventional clinical trial in which 12 patients were prospectively enrolled. Patients with a diagnosis of PD complicated by subfoveal CNV were considered for the study. All patients underwent a complete ophthalmic examination, including ETDRS visual acuity measurement, electroretinogram, electrooculogram, optical coherence tomography, and fluorescein angiography. The treatment protocol began with a loading dose of three consecutive injections at 1-month intervals, followed by injections administered as needed, according to OCT parameters and angiographic features observed during a 24-month follow-up period. The number of eyes with a visual acuity loss of fewer than 15 letters (<3 ETDRS lines), compared with baseline measures, was recorded at the 6-, 12-, and 24-month examinations. RESULTS: Twelve patients completed the planned visits and were included in the study. A visual acuity loss of fewer than 15 letters was not registered in any case at the 6- and 12-month examinations and was found in only one (8%) patient at the 24-month examination. The mean best corrected visual acuity (BCVA) and the mean central macular thickness (CMT) at baseline were 0.73+/-0.34 (logMAR+/-SD) and 276+/-95 microm (SD), respectively. At the 3-month examination, the mean BCVA significantly improved to 0.48+/-0.27, whereas the mean CMT decreased to 220+/-71 microm. At the 12-month examination, the mean BCVA was 0.45+/-0.24, and the mean CMT was 209+/-53 microm. At the 24-month (last) follow-up, the BCVA showed substantial stabilization and the CMT decreased to 199+/-34 microm. No side effects or complications were registered. CONCLUSIONS: Intravitreal bevacizumab injection is a beneficial treatment for subfoveal CNV associated with PD. Further studies are warranted to confirm these initial results and to analyze the morphofunctional changes during the follow-up. (ClinicalTrials.gov number, NCT00391144.).