EyeWorld Asia-Pacific September 2018 Issue

24 EWAP FEATURE September 2018 Views from Asia-Paci c Desmond QUEK, MD Consultant, Adjunct Assistant Professor, Singapore National Eye Centre 11 Third Hospital Avenue, Singapore 168751 Tel. no. +65-90882015 Desmond.quek.t.l@singhealth.com.sg I n my practice in Singapore, where the majority of my patients are Asian, some of the more challenging glaucoma cases have the common problem of conjunctival scarring. Patients with previous ocular surgery involving the superior conjunctiva (e.g. previous retinal surgery or extracapsular cataract surgery) have friable, scarred, conjunctival surfaces that are stuck down, resulting in difficult intraoperative dissection, inadvertent button-hole creation, inability to achieve adequate closure, higher incidence of postoperative needling with anti- metabolites, and increased risk of failure of IOP control. The use of glaucoma drainage devices is usually indicated in these cases, with adjuvants such as mitomycin C (to reduce scarring around the plate) and tutoplast patches (over the tube to prevent conjunctival erosion), relaxing conjunctival incisions (to mobilize more conjunctiva) and autologous conjunctival grafts from either the inferior fornix or contralateral eye (to achieve adequate closure) employed to produce a successful surgical outcome. Other alternatives of reducing intraocular pressure, such as the CyPass supracillary microstent that increases aqueous drainage via the uveoscleral pathway, or micropulse transscleral cyclophotocoagulation that reduces aqueous production in a more graded, controlled fashion (compared to conventional TCP), have the potential to be part of the treatment options for these patients with severe conjunctival scarring. “ The other major challenge in the treatment of glau- coma is noncompliance with topical medications... ” - Desmond Quek, MD The other major challenge in the treatment of glaucoma is noncompliance with topical medications due to a combination of ignorance, inconvenience, side effects, and cost. Trials on the safety and efficacy of sustained-release intraocular pressure lowering medications that can be delivered into the anterior chamber are currently underway, with the promise of providing effective, safe, comfortable, and consistent IOP lowering. This would hopefully reduce the problemof noncompliance and result in better IOP control, preventing disease progression and blindness. Editors’ note: Dr. Quek declared no relevant nancial interests. YAO Ke, MD Eye Institute of Zhejiang University Eye Center, Second Affiliated Hospital of Zhejiang University, College of Medicine 88 Jiefang Road, Hangzhou 310009, China Tel. no. +86-571-87783897 Fax no. +86-571-87783897 xlren@zju.edu.cn I n China, there is another kind of challenging case, who present as acute angle-closure glaucoma combined with white cataract, with IOPs over 60 mmHg though already on all available topical and general IOP-lowering medications. In fear of the difficulty to operate in the extremely shallow anterior chamber as well as the high risk of various complications including hemorrhage and malignant glaucoma, surgeons tend to implement conservative management till IOP is better controlled. However, in some cases, the quick shrinkage of visual field becomes inevitable due to the delay of surgery. Therefore, it is strongly suggested that patients undergo surgery immediately—to soften the eyeball by partial removal of vitreous body via 25-G pars plana vitrectomy, and to perform anterior chamber plasty using viscoelastics, followed by cataract surgery and goniosynechialysis. This procedure can maintain IOP and restore visual acuity in most cases. And for those with uncontrolled postop IOPs, further medication or trabeculectomy are still available. “ ...it is strongly suggested that patients undergo surgery immediately... ” - Yao Ke, MD Of course, it is very challenging when POAG patients are already on all anti- glaucoma medications yet present with uncontrolled IOPs and visual field loss. Some patients are quite young at first visit but suffer from IOPs over 30 mmHg and tubular visual field. For those patients, we should consider not only the efficacy of treatment but also the chance for further surgeries. During the last year, we have performed the new MIGS—ab interno canaloplasty (ABiC) (Ellex, Australia)—in combination with phacoemulsification in three such cases combined with mild cataract. ABiC targets the collapsed Schlemm’s canal as well as the herniation and adhesion of the collector channels so as to rebuild the aqueous humor outflow pathway. After nearly 1 year of follow-up, satisfying efficacy was found—IOPs were well-controlled without any medications in two patients and with merely two types of anti-glaucoma drops in one patient. The greatest advantage of ABiC is that the bulbar conjunctiva is well-persevered, which reserves the opportunities for trabeculectomy or other surgeries in the future. Editors’ note: Dr. Yao declared no relevant nancial interests. Challenging...refractive surgery - from page 23