Hydromassage of macular hole edges for large and persistent full-thickness macular holes

●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with MH.Inclusion criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous vitrectomy.Standard MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 closure.No significant differences were observed in the preoperative OCT variables between the two closure types.Eyes with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent MH.This technique may serve as an effective adjunctive maneuver during challenging MH surgery.

Endophthalmitis in silicone oil-filled eye: A case report

BACKGROUND Endophthalmitis occurring in silicone oil-filled eyes is a very rare occurrence,with reported incidence rates ranging between 0.07%and 0.039%.Traditional methods of management of infectious endophthalmitis include the removal of silicone oil,washout of the vitreous cavity,administration of intravitreal antibiotics,and reinjection of silicone oil.CASE SUMMARY Herein,we report the case of a 39-year-old man with unilateral endophthalmitis after pars plana vitrectomy and silicone oil tamponade.Intravitreal injections of full-dose antibiotics and anterior chamber washout were used to treat the patient.No signs of retinal toxicity were observed during the follow-up period.CONCLUSION Intravitreal full-dose antibiotic injections and anterior chamber washout are promising alternatives to traditional therapies for endophthalmitis in silicone oilfilled eyes.

Fluorescein angiography of retinal vascular involution after intravitreal injection of ranibizumab for retinopathy of prematurity

AIM: To describe the involution patterns of vessel growth of retina through fluorescein angiography(FA) of children, who had been under treatment up to 1 y previously intravitreal ranibizumab(IVR) as monotherapy for retinopathy of prematurity(ROP). METHODS: This is a retrospective study. The medical information and FA of 17 children(34 eyes) whose area of avascular retina from the ora serrata was more than two disc diameters(DD) were analyzed. RESULTS: Among 34 eyes, all were the presence of finger-shaped vessels and arteriolar-venular shunts(100%,34/34 eyes). Popcorn abnormalities were found in most of the eyes(94.1%, 32/34 eyes). Furthermore, in many cases(23.5%, 8/34 eyes), there were leakage persisting in the region of the junction between avascular and vascular retina. In contrast, just 2 eyes(5.9%) showed damage of retinal capillary bed and 3 eyes(8.8%) showed large area of retinal pigment epithelium(RPE) atrophy. CONCLUSION: Although IVR can be very effective in ROP, we should remain cautious as infants may remain avascular peripheral retinas and abnormal vessel. FA allows accurate visualization of vessel abnormalities in eyes with ROP, which will be helpful to affect assessment of disease activity and therapeutic effect.

Foveal structure changes in infants treated with anti-VEGF therapy or laser therapy guided by optical coherence tomography angiography for retinopathy of prematurity

AIM: To evaluate foveal vessel density(VD) and foveal thickness using optical coherence tomography angiography(OCTA) in retinopathy of prematurity(ROP) children treated with laser photocoagulation or anti-vascular endothelial growth factor(VEGF) injection. Additionally, we assessed the relationship between foveal microvascular anomalies and different therapies in ROP children.METHODS: This was a single-center, retrospective study of patients with a diagnosis of type 1 ROP. Twenty-three eyes(14 patients) treated with anti-VEGF injection and twentynine eyes(17 patients) treated with laser coagulation were included in this study. The foveal VD, inner thickness and full thickness were measured at the central 0°, 2° to 8°, and 8° of the retina(centered on the fovea) using OCTA and cross-sectional OCT, respectively.RESULTS: Foveal VD, inner thickness and full thickness were significantly smaller within the central 8° of the retina in ROP children treated with anti-VEGF injection than in those treated with laser photocoagulation(P=0.013, 0.009, 0.036, respectively). The full thickness was also smaller in the anti-VEGF group than in the laser group at the central 0° of the retina(P=0.010). The grade of foveal hypoplasia is lower in the anti-VEGF group than in the laser group(P=0.045). Multivariable analysis did not find any risk factors associated with visual acuity in our study.CONCLUSION: In children with type 1 ROP, the better structural development of fovea in those who were treated with anti-VEGF injection compared with laser photocoagulation are identified. However, visual acuity outcomes are similar 70 mo after the treatments.

The process of retinal vascularization in retinopathy of prematurity after ranibizumab treatment in China

AIM: To explore the process of retinal vascularization and risk factors for retinopathy of prematurity (ROP) treated with intravitreal ran ibizumab (IVR) as mono therapy.METHODS: Infants with type 1 ROP who received IVR as primary treatment from August 2014 to October 2016 at Peking University People's HospitaPs Ophthalmology Department were included in the study. All eyes received 0.25 mg ranibizumab at initial treatment. Retinal vascularization was evaluated clinically. Potential risk factors were also recorded and examined.RESULTS: Retinal vascularization was completed in 126 eyes (62.7%), and retinal vascularization terminated in zone Ⅱ and zone Ⅲ with 16 eyes (7.9%) and 44 eyes (21.9%), respectively, after more than 1-year follow-up. In multivariate regression analysis, lower birth weight (BW), severity of ROP and repeated injections were found to be risk factors for peripheral avascular area (P<0.05).CONCLUSION: In our retrospective study, 29.8% of the ROP eyes treated with ranibizumab have peripheral avascular area at the last follow-up. Lighter BW and the severity of ROP are risk factors. Furthermore, repeated injections also increase the risk of retinal peripheral avascular area remaining in ROP patients.

High-dose ruthenium-106 plaque therapy for circumscribed choroidal hemangioma: a retrospective study of 25 Chinese patients

AIM:To evaluate the efficacy and safety of ruthenium-106(106Ru)plaque radiotherapy at a dose(>50 Gy)higher than recommended(29-50 Gy)for treatment of circumscribed choroidal hemangioma(CCH)in Chinese patients.METHODS:This retrospective study included 25symptomatic CCH patients undergoing 106Ru plaque brachytherapy involving 25 eyes between January 2005and August 2016.Ophthalmic examination was performed at the baseline and at each post-treatment follow-up visit,using best-corrected visual acuity(BCVA),dilated fundus examination,and B-scan ultrasonography.The primary efficacy outcome measures included the changes in BCVA and hemangioma dimensions at the last followup visit from the baseline.RESULTS:The mean follow-up duration was 28.0±26.6(range,12-110)mo.All the hemangiomas were located in the posterior pole except for two involving the fovea.The mean apex dose of 106Ru plaque radiotherapy was84.4±19.7 Gy.The mean BCVA improved from 41.4±29.3(0-97)at the baseline to 53.0±33.8(0-97)ETDRS letters at the last visit(P=0.01).The mean hemangioma height declined from 3.98±0.88(2.40-5.50)mm to 0.84±1.63(0-6.47)mm(P≤0.001),and the greatest linear diameter(GLD)reduced from 9.36±2.23(6.80-15.00)to 7.40±2.45(0-13.00)mm(P≤0.001).Hemangioma size increased in one(4%)eye with a worsened vision,and subretinal fluid completely resolved in all but one patient(4%).Radiationrelated retinopathy was observed in two patients at posttreatment 9 and 11mo,respectively.CONCLUSION:106Ru plaque brachytherapy at a dose(>50 Gy)higher than recommended(29-50 Gy)is an effective treatment regimen for symptomatic CCH associated with significantly improved visual acuity and a favorable safety profile in Chinese patients.

Ruthenium-106 plaque brachytherapy for the treatment of diffuse choroidal hemangioma in Sturge-Weber syndrome

AIM:To evaluate the efficacy of ruthenium-106 plaque brachytherapy for the treatment of diffuse choroidal hemangioma(DCH)in Sturge-Weber syndrome(SWS).METHODS:A total of 8 patients with DCH in SWS managed with plaque brachytherapy were retrospectively included.Patients were treated with ruthenium-106 plaque therapy(median apex dose:83 Gy)at the thickest tumor region.On follow-up,we recorded the tumor thickness,the best-corrected visual acuity(BCVA),subretinal fluid(SRF)status,and complications following treatment.RESULTS:At a median follow-up of 43 mo,tumor regression was observed in all cases,with a complete resolution of SRF and reduction in tumor-thickness.No radiation complications were recorded during the follow up time.CONCLUSION:Ruthenium-106 plaque therapy to the thickest portion of the tumor seems to be a useful treatment in patients with DCH in SWS.

Rapid evaluation of arsenic contamination in paddy soils using field portable X-ray fluorescence spectrometry

Arsenic（As） in paddy fields is deteriorating food security and human health through rice ingestion. Rice is the dominant food source of arsenic exposure to half of the world’s population. Therefore, an in situ effective method for As risk evaluation in paddy soil is strongly needed to avoid As exposure through rice ingestion. Herein, we developed a rapid analytical methodology for determination of As in plant tissues using field portable X-ray fluorescence spectrometry（FP-XRF）. This method was applied to rice roots in order to evaluate the As contamination in paddy soils. The results showed that rice roots with iron plaques were superior to rhizosphere soils for generating FP-XRF signals, especially for field sites with As concentrations lower than the soil detection limit of FP-XRF（30.0 mg/kg）.Moreover, the strong linear relationships of As concentrations between the rice roots and corresponding leaves and grains proved that the rice root, rather than the soil, is a better predictor of As concentrations in rice grains. The research provides an efficient As monitoring method for As contaminated paddy fields by using wetland plant roots with iron plaques and XRF-based analytical techniques.

Multi-UAV collaborative system with a feature fast matching algorithm

We present a real-time monocular simultaneous localization and mapping(SLAM)system with a new distributed structure for multi-UAV collaboration tasks.The system is different from other general SLAM systems in two aspects:First,it does not aim to build a global map,but to estimate the latest relative position between nearby vehicles;Second,there is no centralized structure in the proposed system,and each vehicle owns an individual metric map and an ego-motion estimator to obtain the relative position between its own map and the neighboring vehicles'.To realize the above characteristics in real time,we demonstrate an innovative feature description and matching algorithm to avoid catastrophic expansion of feature point matching workload due to the increased number of UAVs.Based on the hash and principal component analysis,the matching time complexity of this algorithm can be reduced from 0(logN)to 0(1).To evaluate the performance,the algorithm is verified on the acknowledged multi-view stereo benchmark dataset,and excellent results are obtained.Finally,through the simulation and real flight experiments,this improved SLAM system with the proposed algorithm is validated.

Bearing-only Visual SLAM for Small Unmanned Aerial Vehicles in GPS-denied Environments

This paper presents a hierarchical simultaneous localization and mapping（SLAM） system for a small unmanned aerial vehicle（UAV） using the output of an inertial measurement unit（IMU） and the bearing-only observations from an onboard monocular camera.A homography based approach is used to calculate the motion of the vehicle in 6 degrees of freedom by image feature match.This visual measurement is fused with the inertial outputs by an indirect extended Kalman filter（EKF） for attitude and velocity estimation.Then,another EKF is employed to estimate the position of the vehicle and the locations of the features in the map.Both simulations and experiments are carried out to test the performance of the proposed system.The result of the comparison with the referential global positioning system/inertial navigation system（GPS/INS） navigation indicates that the proposed SLAM can provide reliable and stable state estimation for small UAVs in GPS-denied environments.