Glaucoma drainage device implantation and cyclophotocoagulation in the management of refractory glaucoma after Descemet-stripping automated endothelial keratoplasty

AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated endothelial keratoplasty(DSAEK).METHODS:This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery(15 with GDI and 14 with CPC).The main outcome measures were intraocular pressure(IOP),glaucoma surgery success rate(defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation),number of glaucoma medications,endothelial graft status,and best-corrected visual acuity(BCVA).RESULTS:The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries,both for the GDI and CPC groups.Both groups showed significant IOP reduction after glaucoma surgery.The GDI group presented a significantly higher success rate in IOP control than the CPC group(60%vs 21.4%,P=0.03).Both procedures significantly decreased the number of glaucoma medications(P=0.03).Forty percent and 57%of cases in the GDI and the CPC group,respectively,experienced endothelial graft failure during follow-up(P=0.36).Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI group.CONCLUSION:Both GDI and CPC significantly decrease IOP in eyes with glaucoma after DSAEK.GDI is preferable to CPC in refractory glaucoma cases after DSAEK,as it manifests a significantly higher success rate for IOP control,similar endothelial graft failure rate,and relatively preserves BCVA than CPC.

A feasibility study of using biodegradable magnesium alloy in glaucoma drainage device

Technological advances in glaucoma have challenged the traditional treatment paradigm. Historically incisional surgery has been used in cases of advanced disease and/or uncontrolled intraocular pressures resistant to medical or laser interventions. More recently, perhaps due to advancements in imaging, surgery has been suggested to be beneficial earlier in the treatment paradigm. Despite these trends, surgical manipulation of the tissues and unpredictability of wound healing continue to result in surgical failure. Magnesium is an essential element for human body and plays a critically important role in maintaining the functional and structural integrity of several tissues, including the eye. Due to several of its advantageous properties such as non-toxicity, biodegradability, and high biological compatibility, magnesium alloy has attracted great attention as a novel biomaterial. Biodegradable cardiovascular stents made of magnesium alloy have already been introduced into clinical practice. The purpose of this review is to determine if bioabsorbable magnesium alloys can be utilized as a promising candidate for the development of a new generation of glaucoma surgical assistive devices.

Comparison of the efficacy and safety of ultrasonic cycloplasty vs valve implantation and anti-VEGF for the treatment of fundus disease-related neovascular glaucoma

·AIM: To compare the clinical efficacy and safety of ultrasonic cycloplasty(UCP) vs Ahmed glaucoma drainage valve implantation(ADV) in addition to intravitreal antivascular endothelial growth factor(VEGF) for treatment of fundus disease-related neovascular glaucoma(NVG).·METHODS: A total of 43 patients(45 eyes) with NVG secondary to fundus diseases underwent anti-VEGF combined with UCP or ADV from August 2020 to March 2022 were enrolled in this retrospective cohort study. Of them, 14 patients(15 eyes) were treated with both UCP and anti-VEGF as the UCP group and 29 patients(30 eyes) treated with both ADV and anti-VEGF as the ADV group. The success of the treatment was defined as intraocular pressure(IOP) between 11-20 mm Hg with or without using IOP-lowering drugs. IOP measurement, IOP lowering drugs at baseline and follow-ups period and complications were recorded.·RESULTS: The average age was 63.03±9.95 and 52.27±12.89y in ADV and UCP groups, respectively(P=1.947). The fundus pathology included proliferative diabetic retinopathy in 42 eyes and retinal vein occlusion in 3 eyes. All eyes in both groups achieved successful treatment at 3mo. While the success rate was 90.0%(27/30) in the ADV group and 86.7%(13/15) in the UCP group at the last follow-up of 6mo(P>0.05). IOP was significantly lower with reduction of drug use than the baseline in both groups(both P<0.05). And the ADV group needed fewer anti-glaucoma drops than the UCP group from 1d to 3mo. The comfort scores of patients in the ADV group were significantly lower than those in the UCP group in the first week after the operation(P<0.05).·CONCLUSION: UCP is an alternative to the ADV with the same efficacy but non-invasive for the treatment of NVG.

Efficacy and safety of intravitreal ranibizumab with panretinal photocoagulation followed by trabeculectomy compared with Ahmed glaucoma valve implantation in neovascular glaucoma

AIM：To evaluate the efficacy and safety of intravitreal ranibizumab（IVR）with panretinal photocoagulation（PRP）followed by trabeculectomy compared with Ahmed glaucoma valve（AGV）implantation in neovascular glaucoma（NVG）.METHODS：This was a retrospective comparative study.We reviewed the cases of a total of 45 eyes from 45 NVG patients among which 23 eyes underwent AGV implantation and the other 22 underwent trabeculectomy. The causes of neovascular glaucoma included：diabetic retinopathy（25 eyes）,and retinal vein occlusion（20 eyes）.All patients received preoperative IVR combined with postoperative PRP. The mean best-corrected visual acuities（BCVA）were converted to the logarithms of the minimum angle of resolution（log MAR）for the statisitical analyses.Intraocular pressure（IOP）,the log MAR BCVA and surgical complications were evaluated before and after surgery.The follow-up period was 12 mo.RESULTS：A total of 39 cases showed complete regression of iris neovascularization at 7d after injection,and 6 cases showed a small amount of residual iris neovascularization. The success rates were 81.8% and 82.6% at 12 mo after trabeculectomy and AGV implantation,respectively. In the trabeculectomy group,the log MAR BCVA improved at the last follow-up in 14 eyes,remained stable in 6 eyes and decreased in 2 eyes. In 4 cases,slight hyphemas developed after trabeculectomy. A shallow anterior chamber developed in 2 cases and 2 vitreous hemorrhages. In the AGV group,the log MAR BCVA improved in 14 eyes,remained stable in 5 eyes and decreased in 4 eyes. Slight hyphemas developed in 3 cases,and a shallow anterior chamber in 3 cases. The mean postoperative IOP was significantly lower in both groups after surgery（F=545.468,P〈0.05）,and the mean postoperative log MAR BCVA was also significantly improved（F=10.964,P〈0.05）with no significant difference between two groups.CONCLUSION：It is safe and effective to treat NVG with this combined procedure,and we found similar results after IVR＋AGV implantation＋PRP and IVR＋trabeculectomy＋PRP in eyes with NVG.

Review of the Ahmed versus Baerveldt study-5-year treatment outcomes

The results from the tube versus trabeculectomy(TVT)study provided the evidence to support the use of aqueous shunt surgery and its increasing popularity in the world.The Ahmed versus Baerveldt(AVB)study,a randomized controlled study,compared the efficacy and safety between two of the most commonly used glaucoma drainage implants.A significant proportion of the participants had failed trabeculectomy,neovascular or uveitic glaucoma.The 5-year results showed that the cumulative probability for failure is significantly lower for Baerveldt compared to Ahmed group(52.3%vs.40.0%,P=0.039).The most common reason for failure was high intraocular pressure(IOP)but 4%of the Baerveldt group has refractory hypotony.Both surgeries were also effective in reducing dependency on intra-ocular pressure lowering medications but the Baerveldt group is superior in this aspect(median of 1 medication compared to 2 medications for Ahmed group).Both surgeries experienced 60-70%rate of complications but most were self-limiting.The most common long-term complication was corneal decompensation(10%).Overall,the results of the AVB study mirrored the results from the Ahmed Baerveldt Comparison(ABC)study.In conclusion,the 5-year report from the AVB study suggested that the Baerveldt tube is more appropriate for eyes which require much lower IOP such as eyes with advanced glaucoma or in young patients.The Ahmed tube would be more suitable for patients who are at risk of hypotony(such as uveitic and neovascular glaucoma)and those who require immediate IOP lowering after surgery.