Multimodal Imaging of Macular Telangiectasia Type 2: Focus on Vascular Changes Using Optical Coherence Tomography Angiography

PURPOSE. To report morphologic features of idiopathic macular telangiectasia (MacTel) type 2 by means of optical coherence tomography angiography (OCTA) and to compare these findings to fundus fluorescein angiography (FFA), fundus autofluorescence (FAF), confocal blue reflectance (CBR), and spectral-domain OCT (SD-OCT). In addition, foveal vessel density and parafoveal vascular density (PFVD), and foveal retinal thickness and parafoveal retinal thickness (PFRT) were compared between MacTel 2 patients and normal aged-matched controls. METHODS. Eight patients (15 eyes) with MacTel 2 and 17 normal controls (17 eyes) underwent retinal multimodal imaging assessment and grading. Results from different imaging techniques were used to compare interimaging modalities. Objective quantification of retinal vessel density and macular thickness was evaluated in MacTel 2 patients (15 eyes). RESULTS. In MacTel 2 eyes a comparison of OCTA to the other imaging techniques showed that the strongest correlations were present with SD-OCT, early FFA, and late FFA. Moderate correlations were found between OCTA and CBR and FAF. Foveal vessel density was significantly lower in MacTel 2 eyes than control eyes both in the superficial plexus (23.74% vs. 33.14%; P = 0.003) and in the deep plexus (24.63% vs. 34.21%; P = 0.005). Superficial PFVD was significantly different in the two groups (47.06% vs. 51.40%; P = 0.005) but not the deep PFVD. Foveal retinal thickness was 214.13 mu m in MacTel 2 eyes and 258.18 mu m in normal controls, and PFRT was 279.60 and 323.29 mu m, respectively (P CONCLUSIONS. Optical coherence tomography angiography is useful for retinal vasculature characterization in MacTel type 2 patients and showed a high correlation with well-established imaging techniques

Correlation between Choriocapillaris Density and Retinal Sensitivity in Stargardt Disease

The aim of this work was to characterize the choriocapillaris (CC) in patients with Stargardt disease (STGD) using the swept source widefield optical coherence tomography angiography (SS WF OCTA) and to compare CC perfusion density to retinal sensitivity, analyzed using microperimetry (MP). This cross-sectional study included 9 patients (18 eyes) with STGD and central CC atrophy (stage 3 STGD). The CC was analyzed using SS WF OCTA and areas of different CC impairment were quantified and correlated with retinal sensitivity analyzed using MP. The main outcome measures were the percent perfused choriocapillaris area (PPCA), retinal sensitivity, and correlation between PPCA and retinal sensitivity. Seventeen eyes of 9 patients suffering from stage 3 STGD were analyzed. SS WF OCTA revealed a vascular rarefaction in central atrophic zones and a near atrophy halo of choriocapillaris impairment. In all eyes were noticed a central atrophy (CA) area with absolute absence of CC that corresponded to 0 dB points at MP, a near atrophy (NA) zone of PPCA impairment that included points with decreased sensitivity at MP and a distant from atrophy (DA) zone with higher PPCA and retinal sensitivity values. The mean difference of PPCA and retinal sensitivity between NA and CA and DA and CA was statistical significantly different (p < 0.01), the latter showing higher values. A direct relationship between PPCA and retinal sensitivity was found (p < 0.001). Choriocapillaris damage evaluated using SS WF OCTA correlates with MP, these data suggest that CC impairment may be a predictor of retinal function in patients with STGD

Early retinal flow changes after vitreoretinal surgery in idiopathic epiretinal membrane using swept source optical coherence tomography angiography

(1) Background: The aim of this observational cross-sectional work was to investigate early retinal vascular changes in patients undergoing idiopathic epiretinal membrane (iERM) surgery using swept source optical coherence tomography angiography (SS-OCTA); (2) Methods: 24 eyes of 24 patients who underwent vitrectomy with internal limiting membrane (ILM) peeling were evaluated pre- and postoperatively using SS-OCTA system (PLEX Elite 9000, Carl Zeiss Meditec Inc., Dublin, CA, USA). For each eye, five 6x6-mm OCTA volume scans were acquired by two observers independently. The en face images of superficial capillary plexus (SCP) were then exported to imageJ and a semi-automated algorithm was used for subsequent quantitative analysis. Perfusion density (PD), vessel length density (VLD), vessel diameter index (VDI) and vessel tortuosity (VT) of SCP were evaluated in both the parafoveal (2.5 mm diameter) and perifoveal areas (5.5 mm diameter); (3) Results: At OCTA analysis statistically significant differences were found between controls and diseased eyes for all parameters in parafoveal and perifoveal regions (p < 0.001; p < 0.05) except for perifoveal VLD. During 6-month follow up, both anatomical/perfusion and functional parameters showed a statistically significant improvement if compared to preoperative values. In detail, at one-month post vitrectomy, VLD and VT significantly changed in parafoveal region (p = 0.043; p = 0.045), while PD and VDI showed a trend of increase in both parafoveal and perifoveal region. At 6 months after surgery, PD, VLD and VT of parafoveal region significantly improved (p = 0.021, p = 0.018, p = 0.047 respectively). (4) Conclusions: SS-OCTA provides a quantitative and qualitative analysis of the superficial capillary plexus allowing for early vascular changes assessment after vitrectomy with iERM and ILM peeling

How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

Comparison between RTW VCO and LC QVCO 12 GHz PLLs

This paper reports comparisons between RTWVCO and LC QVCO 12 GHz PLLs, designed in a 130 nmCMOS technology for satellite communication applications.The phase noise at 1 MHz offset from the carrier is-102 dBc/Hz for the RTW VCO PLL and -98 dBc/Hz forthe LC QVCO PLL, and the power consumption is 39 and17 mW, respectively

Comparison between RTW VCO and LC QVC 12 GHz PLLs

This paper reports comparisons between RTW VCO and LC QVCO 12 GHz PLLs, designed in a 130 nm CMOS technology. The phase noise at 1MHz offset from the carrier is -102 dBc/Hz for the RTW VCO PLL and -98 dBc/Hz for the LC QVCO PLL, and the power consumption is 39mW and 17 mW, respectively

Optical coherence tomography angiography assessment of vascular effects occurring after Aflibercept intravitreal injections in treatment-naive patients with wet AMD

PURPOSE: To investigate vessel changes occurring after aflibercept injections in treatment-naive exudative age-related macular degeneration patients. METHODS: Fifteen eyes of 15 patients affected by wet age-related macular degeneration were enrolled in the study. All the patients had a diagnosis of Type 1 choroidal neovascularization and were treated with 3 monthly aflibercept intravitreal injections (IVI). Subjects were evaluated by means of optical coherence tomography angiography at baseline, the day after the first injection and one month after both the first and the second IVI. At last, all the patients were followed up to 2 months after the third IVI. RESULTS: Foveal superficial vascular plexus flow density was 29.01% (21.13-37.32%) at baseline and was significantly reduced as soon as 1 month after the first IVI (median: 20.78%; interquartile range: 14.75-23.13%; P = 0.017). Parafoveal superficial vascular plexus flow density was 47.09% (44.91-51.72%) at baseline and significantly decreased as soon as 1 month after the second IVI (median: 44.40%; interquartile range: 41.59-49.29%; P = 0.034). Choroidal neovascularization lesion area remained stable throughout the follow-up. Nevertheless, interestingly, choroidal neovascularization flow area was significantly reduced as soon as the next day the first IVI (median: 0.37 mm and interquartile range: 0.27-0.72 mm at baseline; median: 0.30 mm and interquartile range: 0.24-0.64 mm at 1 day after the first IVI; P = 0.047). CONCLUSION: Intravitreal aflibercept injections are associated with a significant change in native retinal and choroidal vasculature. Moreover, the treatment did not cause a reduction in lesion area, but rather reduced the flow in the choroidal neovascularization

Comparison of Guided and Unguided Ocriplasmin Injection for the Treatment of Vitreomacular Traction: A Preliminary Study

This retrospective quality control study aimed at comparing resolution in patients treated with intravitreal ocriplasmin (IVO) using two injection techniques, classical injection procedure (unguided) and targeted injection using a surgical microscope with a 30-gauge 1-inch needle (guided) for the treatment of focal VMT without macular hole. The two groups presented a statistically significant difference in terms of resolution of VMT within the first month following treatment: 1/7 for the unguided group versus 6/7 for the guided group (p = 0.0291). The majority of the guided group presented an earlier resolution than the single resolved case in the unguided group. The results of this preliminary study indicate that the injection of ocriplasmin closer to the site of VMT results in the resolution in a higher number of cases and that this resolution occurs in a short time interval