SCIENTIFIC POSTER_Elena Kozina

OCT-criteria for a potential risk of pigment epithelium (PE) tear development, PE reattaching and PED resistance at A-VEGF therapy of patients with wet AMD, accompanied by high PE detachment are determined retrosprctively for predicting the possible treatment outcome and determination of the optimal mode of A-VEGF injection.

General Considerations:

In clinical practice the different morphological forms of pigment epithelium detachments (PED) for the AMD wet form (WF) may respond differently to the relief of exudative macular process under the action of blocker of human vascular endothelium growth factor. Morphofunctional dynamics (PED) for A-VEGF therapy proceeds in three main ways: 1) PED reattaching with the improvement of visual acuity, 2) lack of dynamics, 3) pigment epithelium tear (PET) formation with a reduction of visual functions. It is known that the PE tear is caused by tangential traction on the border between detached and undetached PE. According to some authors, the frequency of such changes on the background of A-VEGF therapy ranges from 0.6% to 35 % (Smith B.T. et all, 2009; Panos GD. et all, 2013; Clemens CR. et all, 2013). Optical coherence tomography (OCT) of the retina is a highly informative method of patient examination with AMD WF, which allows to carry out qualitative (signal morphology and reflectivity) and quantitative (retinal thickness and its volume in the scanning area) analyses of the retina.

Purpose:

To determine retrospectively OCT-criteria for a potential development of PE morphological changes at A-VEGF therapy of patients with wet AMD, which is accompanied by high pigment epithelium (PE) detachment, for predicting of possible treatment outcome and determination of the optimal mode of A-VEGF injection.

Materials and methods:

The retrospective analysis of OCT data and functional results of treatment of 300 eyes with AMD wet form by intravitreal A-VEGF injection was performed. Diagnosis is confirmed by OCT, fluorescein angiography (FAG) and ophthalmoscopy data. The qualitative analysis of the original OCT in group I with no changes in the PED after A-VEGF therapy (11 eyes), in group II with PE tear after A-VEGF therapy (6 eyes) and in group III – with PE high detachment reattaching (7 eyes), was carried out. The patients’ ages ranged from 70 to 83 years. OCT of retinal macular zone was performed with SOCT CIRRUS HD (Carl Zeiss) with a resolution of 5 microns, before the treatment and 1 month after the injection. FAG was carried out as required according to the standard procedure. Results and discussion. In general group of patients the high PE detachment was detected in 24 people, which was 8%. One month after intravitreal A-VEGF injection 6 PE tears were defined, which was 2%. In 7 eyes PE was reattached (2.5%). In other cases, the PED morphology did not change – 11 eyes (4%). The comparative characteristic of macular zone OCT data Table 1 OCT-criteria Group I Group II Group III Number of eyes (%) The prevalence of serous neuroepithelium detachment Less than 100 microns Less than 300 microns More than 1000 microns (average diameter, micron) 11 eyes (100%) 6 eyes (100%) 7 eyes (100%) The presence of the pigment epithelium defect 1 eye (9%) 1 eye (16%) 7 eyes (100%) Bruch’s membrane shielding 1 eye (9%) 6 eyes (100%) Wrinkled PED 6 eyes (100%) Cystic PED 11 eye (100%) – 6 eyes (86%) Height of PED To 1 000 microns To 500 microns To 800 microns 7 eyes (65%) 6 eyes (100%) 6 eyes (86%) Budding zone of choroidal neovascularization (CNV) in PE Less than 700 microns More than 1000microns 6 eyes (100%) 5 eyes (72%) From the data presented in Table 1, it is seen that in all studied eyes of the first group in the macular zone according primary OCT data there were high cystic pigment epithelium detachment without defects, budding zones of choroidal neovascularization (CNV) and subretinal exudative activity. The patients of the second group in the macular zone according primary OCT had Bruch’s membrane shielding and wrinkled form of PE elevation not more than 500 microns. Pigment epithelium defect was identified only in 1 case, exudative neuroepithelium detachments in all cases were local. OCT data in the third group of patients were characterized by the presence of common neuroepithelium detachments, high cystic PE detachments (up to 800 microns), defect visualization in PE and budding zones of choroidal neovascularization (CNV) in PE, prevalence rate of more than 1000 microns. Visual acuity dynamics in the examined patients Table 2 Examination period Group I (11 eyes) Group II (6 eyes) Group III (7 eyes) Average visual acuity with correction Before treatment 0.4 0.5 0.3 After treatment 0.4 0.1 0.45.

The patients’ visual acuity in group I after treatment did not change, after the treatment of group II the patients’ visual acuity decreased to 0.1. Functional results of group III patients – visual acuity increased by an average of 0.15.

Conclusions:

OCT-criteria of PE tear risk, leading to a permanent visual acuity reduction in A-VEGF therapy of patients with wet AMD are: 1. The intensity of subretinal exudation: neuroepithelium local detachment with prevalence of not more than 300 microns; Bruch’s membrane shielding. 2. The PE detachment form: wrinkling; height up to 500 microns. 3. PE status: absence of defects in the PE; budding zone of CNV in the PE with prevalence of less than 700 microns. The absence of defects in the PE, Bruch’s membrane shielding, exudative subretinal activity, is prognostic criteria of wet AMD resistant to the A-VEGF therapy. The presence of OCT risk components of PE tear in patient requires increased caution in planning A-VEGF therapy, as well as the choice of repeated injections individual mode. The presence of OCT resistance signs to A-VEGF therapy raises the question of advisability of intravitreal injections treatment refusing. Retrospectively OCT-criteria for a potential risk of pigment epithelium (PE) tear development, PE reattaching and PED resistance at A-VEGF therapy of patients with wet AMD, accompanied by high PE detachment are determined for the predicting of possible treatment outcome and determination of the optimal mode of A-VEGF injection.