Retinal microvascular changes in unilateral functional amblyopia detected by oct-angiography and follow-up during treatment.

OBJECTIVE: To evaluate the macular microvascular changes using optical coherence tomographic angiography (OCT-A) in children with unilateral amblyopia and their reversibility during treatment. METHODS: Patients with unilateral strabismic or anisometropic amblyopia or residual amblyopia from early congenital cataract surgery, examined between October 2019 and March 2021, were included. Vessel density and perfusion density in the superficial capillary plexus and area, perimeter and circularity of the foveal avascular zone (FAZ) were analysed using OCT-A in amblyopic eyes, contralateral eyes and control group healthy eyes. Correlation analyses between the microvascular parameters and the visual acuity were performed. In a pilot study on a few patients from the amblyopic cohort, longitudinal follow-up during treatment was also performed. RESULTS: A total of 128 eyes of 64 patients were included: 32 amblyopic eyes compared with 32 contralateral eyes and 64 control eyes. Vessel density and perfusion density in the superficial capillary plexus were significantly lower in amblyopic eyes compared to control eyes in 6 × 6 mm (p < 0.02) and 3 × 3 mm (p < 0.01) scans. Correlation analyses showed a linear decrease in vessel density and perfusion density with decreasing visual acuity. The microvascular changes observed were reversible with the occlusion treatment of amblyopia (p < 0.001). CONCLUSIONS: The study found a decrease in vessel density and perfusion density in the macula of children with unilateral functional amblyopia. These microvascular changes were correlated with visual acuity and appeared to be reversible with treatment of amblyopia. On the whole, OCT-A appears to be a relevant complementary examination when it comes to diagnosing and monitoring functional amblyopia.

Human amniotic membrane application in oral surgery-An ex vivo pilot study.

Objectives: The purpose of this pilot porcine study was to explore and illustrate the surgical application of human amniotic membrane (hAM) in an ex vivo model of medication-related osteonecrosis of the jaw (MRONJ). Material and methods: Five oral and maxillofacial surgeons participated to this study. MRONJ was simulated on porcine mandible specimens. hAM was applied using four different techniques: implantation with complete coverage, implantation with partial coverage, apposition and covering graft material. At the same time, the surgeons evaluated how well the hAM handled and its physical properties during the surgery. Results: Surgeons found that hAM had suitable mechanical properties, as it was easy to detach from the support, handle, bind to the defect and bury. hAM was also found to be strong and stable. The "implantation with complete coverage" and "implantation with partial coverage" techniques were the preferred choices for the MRONJ indication. Conclusion: This study shows that hAM is a graft material with suitable properties for oral surgery. It is preferable to use it buried under the gingiva with sutures above it, which increases its stability. This technical note aims to educate surgeons and provide them with details about the handling of hAM in oral surgery. Clinical relevance: Two surgical techniques for hAM application in MRONJ were identified and illustrated. hAM handling and physical properties during surgery were reported.

Questions about Residual Cell Viability in Cryopreserved Human Amniotic Membrane and Its Impact on Clinical Applications.

We questioned the relevance of evaluating residual cell viability in human amniotic membrane (hAM) after its cryopreservation since cell survival is controversial and its ability to act as a matrix (including the presence of growth factors and cytokines) appears to be most important for tissue regeneration purposes. We also discussed the usefulness of osteodifferentiating amniotic cells in whole hAM for bone repair applications. We have evidence that determining residual cell viability after cryopreservation and hAM osteodifferentiation is not justified.

Predictive factors for exudation of quiescent choroidal neovessels detected by OCT angiography in the fellow eyes of eyes treated for a neovascular age-related macular degeneration.

BACKGROUND: To identify predictive factors for exudation for quiescent choroidal neovessels (qCNV) in the fellow eyes of eyes treated for a neovascular age-related macular degeneration (AMD). METHODS: Prospective observational study. One hundred and forty-four contralateral eyes of 144 patients treated for wet AMD were analysed. At a baseline visit, multimodal imaging including dye angiographies and optical coherence tomography angiography (OCT-A) was performed in order to detect qCNV. Patients were followed up for 12 months with a monthly assessment. The manifestation of any type of exudation (either intra- or subretinal fluid or hyperreflective subretinal material) was monitored. RESULTS: The prevalence of qCNV in the treatment-naive eyes was 15.9% with an incidence over a 12-month period of 2.8%. In total, 40.7% of the overall neovessels remained stable with no sign of exudation, while 59.3% presented some fluid during the follow-up. A statistically significant relationship was established for the following variables preceding the exudation: increase in central macular thickness (OR = 116; 95% CI [4.74; 50530] p = 0.038), increase in pigment epithelial detachment height (OR = 1.76; 95% CI [1.17; 3.18] p = 0.021) and width (OR = 1.53; 95% CI [1.12; 2.62] p = 0.042), increase in neovessels' surface on OCT-A (OR = 6.32; 95% CI [1.62; 51.0] p = 0.033), emergence of a branching pattern (OR = 7.50; 95% CI[1.37; 61.5] p = 0.032) and appearance of a hypointense halo surrounding the lesion (OR = 10.00; 95% CI [1.41; 206] p = 0.048). CONCLUSIONS: The risk of exudation in the treatment-naive fellow eyes of eyes treated for neovascular AMD was notably increased in the presence of qCNV. The biomarkers identified will help to detect their activation in order to ensure prompt antiangiogenic therapy.