Ophthalmology in the time of COVID-19: experience from Hong Kong Eye Hospital

AIM:To review international guidelines and to share our infection control experience during the coronavirus disease 2019(COVID-19)pandemic at a tertiary eye centre in Hong Kong.METHODS:Infection control guidelines and recommendations from international ophthalmological bodies are reviewed and discussed.The measures at our hospital were drawn up as per international and local health authorities’guidelines and implemented with the collaboration of doctors,nurses and administrative staff.RESULTS:The aims of our infection control measures are to 1)minimize cross-infection within the hospital;2)protect and support hospital staff;3)ensure environmental control.To minimize the risk of cross-infection,outpatient attendance and elective surgery have been reduced by 40%,and general anesthesia procedures were reduced by 90%.Patients entering the hospital are screened for fever,travel history,contact and cluster history,and COVID-19 related symptoms.To protect and support hospital staff,we ensure provision of adequate personal protective equipment(PPE)and provide clear guidelines on the level of PPE needed,depending on the clinical situation.Other protective measures include provision of work uniforms,easy access to alcohol-based hand rub,opening new lunch areas,implementation of self-monitoring and self-reporting systems,and communication via online education and updates.Finally,environmental control is achieved by ensuring regular disinfection of the hospital premise,enhancing ventilation,and usage of disposable ophthalmic instruments.CONCLUSION:Our multi-pronged approach to infection control is,so far,successful in minimizing infection risks,while allowing the maintenance of essential ophthalmic services.

息肉状脉络膜血管病和脉络膜新生血管患者房水中血管内皮生长因子和色素上皮衍生因子的表达水平

PURPOSE: To determine the aqueous levels of vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) in patients with active polypoidal choroidal vasculopathy (PCV) and choroidal neovascularization (CNV)-secondary to age-related macular degeneration (AMD) and pathologic myopia. DESIGN: Prospective,comparative control study. METHODS: Aqueous humors were collected from 32 eyes of 32 patients for either active PCV or CNV. Among them,11 eyes had active and symptomatic PCV,12 eyes had active CNV secondary to AMD,and nine eyes had active CNV of pathologic myopia. Levels of VEGF and PEDF were determined by commercially available enzyme-linked immunosorbent assay kits. A group of 10 aqueous samples from 10 patients who underwent cataract surgery without other ocular or systemic diseases comprised the controls. RESULTS: VEGF concentrations in aqueous humor were markedly increased in patients with PCV,CNV of AMD,and CNV of myopia when compared with the controls (analysis of variance ANOVA,P < .001). VEGF levels in eyes with PCV were,however,significantly lower than those of exudative AMD (P=.045)-. The PEDF levels were also significantly different among the groups (ANOVA,P=.001),and we observed increased levels in PCV,CNV of AMD,and CNV of myopia. CONCLUSIONS: VEGF and PEDF factors were coexpressed and increased with positive correlation in aqueous humor of eyes with active PCV. The different levels of both factors in eyes of PCV and AMD might suggest distinct clinical entities or different angiogenesis courses between PCV and AMD.

Commentary on effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE)

Background Relative pupil block is the most common mechanism of intraocular pressure(IOP)elevation in primary angle-closure glaucoma(PACG)and primary angle closure(PAC).The standard approach of treating PACG and PAC is laser peripheral iridotomy(LPI)with or without additional IOP-lowering agents.If IOP remains poorly controlled,lens removal could be considered,especially if the patient has co-existing symptomatic cataract.The efficacy of lowering IOP by lens extraction for patients with co-existing cataract and PACG or PAC is known(1-4).

维替泊芬光动力疗法治疗有症状的息肉状脉络膜血管病变:前瞻性病例1年的研究结果

Objective To determine the efficacy of photodynamic ther-apy(PDT)with verteporfin as a treatment for s ymptomatic polypoidal choroidal vasculopathy(PCV).Design Prospective consecutive,2-centered,noncomparative in-terventional case series.Particip ants Twenty-one Asian patients with 22eyes presenting with serosanguinous maculopathy due to PCV and an initial best-corrected vi-sual acuity(BCVA)of 20/40or worse were recruited prospectively.All patients had angiographic leakage seen on fluorescein angiograms (FAs )and features of PCVseen with indocyanine green(ICG)angiography.Methods In-travenous infusion of verteporfin a t a dose of 6mg /m 2 of body surface area over 10minutes was administered.Five minutes after the completion of infu sion,a 689-nm laser was applied for 83seconds,with a lig ht dose of 50J /cm 2 .The laser spot size was chosen to cover the polyps and the surrounding abnormally dilated choroidal vessels shown on ICG angiography plus an extra 1000-μm margin.Photo-dynamic therapy retreatment was performed if leakage from the polyps was found on both repeat FA s and ICG an-giography at regular 3-month follow-up intervals.Main outcome measures The proportion of e yes with stable or improved vision at a 1-year follow-u p.Secondary outcome measures included change in mean BCV A and the changes in clinical and angiographic featur es in FAs and ICG an-giography.The total number of PDT se ssions and any complications were also recorded.R esults Stable or im-proved vision was achieved in 21(95%)of the 22eyes at the 1-year follow-up.Ten(45%)eyes had a moderate gain in vision(improved by≥3lines),whereas 1(5%)eye suffered a moderate visual loss(decrease by≥3lines).The mean BCVA improved from a logarithm of the minimum angle of resolution(logMAR)of 0.73to 0.60,an equivalent of 1.3lines of improvement.The change in logMAR BCVA at 12months was statisti cally significant (Wilcoxon signed-ranks test,P=0.009).Complete ab-sence of leakage in FAs and total regression of the polyps in ICG angiography were observed in 20(91%)and 21(95%)eyes,respectively.Severe loss of v ision due to massive subretinal hemorrhage occu rred in 1eye;other-wise,there were no other serious tre atment-related adverse events.Conclusions The 1-year resu lts of PDT in treating PCV of the macular type with serosanguinous presentations are encouraging.Further studies wi th longer follow-up and randomized controlled trials are wa rranted to assess the long-term safety and efficacy of PDT relative to observation or other treatment modalities.

应用于虹膜缺失和白化病患者的黑色隔膜无虹膜型人工晶体

Background: Our aim was to assess the safety and efficacy of primary and secon dary implantation of a black diaphragm aniridia intraocular lens (IOL) in patien ts that lacked a complete iris diaphragm. Methods: This was a retrospective non -comparative study of six eyes in five patients with iris defects. The causes o f such defects included congenital aniridia, traumatic aniridia, and oculocutane ous albinism. Three eyes underwent primary implantations of a black diaphragm IO L, and three eyes were given secondary implantations. The visual acuity, subject ive severity of glare, postoperative anatomical outcome and any intraoperative o r postoperative complications were reviewed. Results: The mean follow-up period was 20.6 months (range 3-29 months. All patients showed stable or improvement in best-corrected visual acuity postoperatively. Glare and photophobia had impr oved subjectively in all patients after implantation of the black diaphragm IOL. Intraoperative complication included one case of hyphaema and iris damage durin g insertion of the IOL. Postoperative complications included intraocular inflamm ation with choroidal detachment, secondary glaucoma, and persistent epithelial d efect after surgery. None of the patients developed decentration of IOL after su rgery. Conclusion: The black diaphragm aniridia IOL is useful in the management of the condition in patients with iris deficiency including oculocutaneous albin ism. Intraoperative and postoperative complications are not uncommon, and patients should be monitored carefully in the perioperative period.

先天性上睑下垂患儿行自身掌长肌额肌悬吊术的长期疗效

Purpose: To investigate the long-term outcome of using autogenous palmaris longus tendon (PLT) sling for correcting congenital ptosis in children. Methods: This is an observational case series involving 15 eyelids of 14 consecutive children with congenital ptosis who underwent frontalis suspension surgery using PLT in a university teaching hospital. Results: One child had bilateral ptosis and the other children had unilateral ptosis. The age of patients at the time of surgery ranged from 2 to 7 years, with an average of 4.7 years. At a mean follow-up of 92 months (range, 80-104 months), all eyelids were successfully corrected with good lid height. No recurrence or other postoperative complications were encountered except one patient who developed a small skin fold over the PLT harvest site. Conclusion: Long-term lid position is remarkably stable after surgical correction using PLT. PLT sling appears to be a safe and effective treatment for children with congenital ptosis requiring frontalis sling operation. It could be a good alternative to autogenous fascia lata, and further studies, to compare these two sling materials seem warranted.

球周麻醉在中国流动眼站7～15岁儿童白内障手术中的应用

Aim:To evaluate the feasibility and acceptability of the use of peribulbar anaesthesia(PA)in paediatric cataract surgery in rural areas in China,where there are limitations in expertise and equipment for general anaesthesia(GA).Methods:We prospectively evaluated the feasibility and acceptability of carrying out paediatric cataract surgery under PA in children aged 7-15 years.Informed consent was obtained from the subjects and their parents.Children were assessed for their suitability for PA.Peribulbar anaesthesia was given as a peribulbar block using a 2% lidocaine,0.5% bupivacaine-hyaluronidase mixture administered before lens aspiration with intraocular lens implantation.The acceptability of the PA was evaluated by questionnaire.Results:A total of 19 patients were recruited.Their mean age was 12± 2 years(range 7-15 years).None required conversion to GA.All subjects regarded PA as either totally acceptable(63.2%)or acceptable(36.8%).The mean pain scores(from 0 to 100)during the injection and surgery were 28± 26 and 6± 8,respectively.Seventeen patients(89.5%)said they would prefer PA if choices in anaesthesia were offered again.Conclusions:Peribulbar anaesthesia can be considered as a viable option in selected children undergoing cataract surgery when facilities for safe and optimal general anaesthesia are unavailable.

白内障伴糖尿病性黄斑水肿的患者行超声乳化联合曲安西龙玻璃体腔注射:6个月的前瞻性先导研究

Aims: To assess the safety and efficacy of phacoemulsification with intravitreal triamcinolone (ivTA) injection in diabetics with cataract and clinically significant macular oedema (CSMO). Methods: A total of 19 eyes of 15 consecutive diabetic patients with cataract and CSMO were prospectively recruited. Patients underwent phacoemulsification and intraocular lens implantation with 4 mg ivTA injection at completion of surgery. Patients were followed up on day 1, then weekly for 1 month, and thereafter monthly until 6 months postoperatively. Best corrected visual acuity (BCVA), central macular thickness (CMT) measured by optical coherence tomography, and adverse events were recorded. Results: In total, 17 eyes completed 6 months of follow-up. In all, 58.8% showed improvement in BCVA of ≥ 2 lines, with statistically significant improvement in mean Snellen BCVA of 2.4 lines at 6 months. The peak BCVA was achieved at 4 months. The mean CMT decreased from a baseline of 449 pm to a minimum of 321 ± 148 μ m (28.5% reduction) achieved at 2 months, with statistically significant reduction at all postoperative time intervals until 6 months. Of 17 eyes, 4 (23.5% ) developed transiently elevated intraocular pressure that normalised by 6 months in all but one patient. No injection or surgery-related complications were encountered. Conclusions: Phacoemulsification with concurrent 4 mg ivTA injection appears to be a safe option for managing diabetics with cataract and CSMO. However, large-scaled randomised controlled trials are necessary for delineating the relative contributions of cataract removal and CMT reduction to visual improvement. Moreover, the transient effect on CMT may warrant further studies to determine optimal timing and dosage of further ivTA injections.

Clinically relevant factors associated with quantitative optical coherence tomography angiography metrics in deep capillary plexus in patients with diabetes

Background:To test clinically relevant factors associated with quantitative artifact-free deep capillary plexus(DCP)metrics in patients with diabetes mellitus(DM).Methods:563 eligible eyes(221 with no diabetic retinopathy[DR],135 with mild DR,130 with moderate DR,and 77 with severe DR)from 334 subjects underwent optical coherence tomography-angiography(OCT-A)with a swept-source OCT(Triton DRI-OCT,Topcon,Inc.,Tokyo,Japan).Strict criteria were applied to exclude from analysis those DCP images with artifacts and of poor quality,including projection artifacts,motion artifacts,blurriness,signal loss,B-scan segmentation error,or low-quality score.A customized MATLAB program was then used to quantify DCP morphology from the artifact-free DCP images by calculating three metrics:foveal avascular zone(FAZ),vessel density(VD),and fractal dimension(FD).Results:166(29.5%)eyes were excluded after quality control,leaving in the analysis 397 eyes(170 with no DR,101 with mild DR,90 with moderate DR,36 with severe DR)from 250 subjects.In the multiple regression models,larger FAZ area was associated with more severe DR(β=0.687;p=0.037),shorter axial length(AL)(β=−0.171;p=0.003),thinner subfoveal choroid thickness(β=−0.122;p=0.031),and lower body mass index(BMI)(β=−0.090;p=0.047).Lower VD was associated with more severe DR(β=−0.842;p=0.001),shorter AL(β=0.107;p=0.039),and poorer visual acuity(VA)(β=−0.133;p=0.021).Lower FD was associated with more severe DR(β=−0.891;p<0.001)and with older age(β=−0.142;p=0.004).Conclusions:Quantitative artifact-free DCP metrics are associated with VA,DR severity,AL,subfoveal choroidal thickness,age,and BMI in diabetic patients.The effects of ocular and systemic factors should be considered for meaningful interpretations of DCP changes in DM patients.

Clinical features of retinal diseases masquerading as retrobulbar optic neuritis

Background Managements of optic neuritis （ON） included high-dose corticosteroids or combined with systemic immunomodulatory agents. It was important to make a correct diagnosis of ON before initiation of treatment. The purpose of the study was to report and analyze the clinical features of retinal diseases in patients who were misdiagnosed as having retrobulbar ON. Methods Retrospective review of 26 patients （38 eyes） initially diagnosed with retrobulbar ON but were ultimately diagnosed with retinal or macular diseases. Data obtained from fundus examination, fluorescence fundus angiography （FFA）, automated static perimetry, full-field electroretinogram （ffERG）, multifocal electroretinogram （mfERG）, and optical coherence tomography （OCT） were evaluated. Results Thirty-eight eyes of 26 patients were found to have misdiagnosis of retrobulbar ON, based on normal or slight abnormal fundus findings and abnormal visual evoked potentials （VEP）. The mean age of the patients was 34 years and the correct diagnosis of the patients included acute zonal occult outer retinopathy （AZOOR, 15 eyes, 14 patients）, occult macular dystrophy （OMD, 8 eyes, 4 patients）, cone or cone-rod dystrophy （10 eyes, 5 patients）, acute macular neuroretinopathy （AMNR, 3 eyes, 2 patients）, and cancer-associated retinopathy （CAR, 2 eyes, 1 patient）. Conclusion When attempting to diagnose retrobulbar ON in clinical practice, it is crucial to carry out necessary examinations of the retinal function and morphology to decrease misdiagnosis.