The Education Committee carefully selects presentations from the WGC-2019 for your benefit. This month Tanuj Dada introduces the sessions: Beyond IOP: Are there other modifiable risk factors in glaucoma? and Glaucoma and lens extraction: where are we?.
Beyond IOP: Are there other modifiable risk factors in glaucoma?
Iatrogenic glaucoma: the story of blood pressure treatment
Dr. Fotis Topouzis
Dr. Topouzis said that our understanding about the complexity of relationship between blood pressure, anti-hypertensive treatment and glaucoma is limited. He said low blood pressure on treatment might be considered a modifiable risk factor in glaucoma. He also suggested setting a target blood pressure similar to target IOP in these patients.
Are other diseases playing a role in my patient’s glaucoma?
Dr. Mitchell Lawlor
Dr. Lawlor highlighted the importance of ruling out non-glaucomatous pathologies in a case of suspected or established glaucoma. He emphasized that if disc changes and visual field defects do no corroborate, neuroimaging should be done.
Can dietary changes help prevent glaucoma progression?
Dr. Birt discussed available evidence in literature. She quoted a few studies, which suggested increased intake of fruits and vegetables, vitamin A and C and Gingko Biloba might offer some protection against glaucoma. She also mentioned that increased intake of caffeine causes elevation in IOP. She concluded by saying that there is little evidence to suggest that adhering to a particular diet or dietary supplement has specific benefits in the prevention or modulation of POAG.
Can physical activity prevent glaucoma?
Dr. Chrysostomou presented the results of their study on aged mice where acute retinal injury was induced by raising the intraocular pressure to 50mmHg for 30mins. Mice were made to exercise before or after inducing the injury. She mentioned that exercise offered benefits like improved RGC functional recovery, reduced astrocytic gliosis and microglia activation etc. in mice. She concluded by saying that they still need to determine whether similar interventions offer protection in chronic animal glaucoma models.
Going beyond the eye: does visual perception help us understand brain function?
Allison M McKendrick
Dr. McKendrick discussed how glaucoma impacts the daily visual experience. She mentioned that there is impaired object perception, motion processing and depth analysis in patients even with intact central visual fields.
Glaucoma and lens extraction: where are we?
Phaco considerations in the pseudo exfoliation eye
Dr. Haripriya started by enumerating intraoperative challenges during phacoemulsification in a pseudo exfoliation eye. She presented the results of Aravind Pseudoexfoliation study (APEX). She highlighted that the rates of intraoperative complications and IOL decentration at 5 years were not higher in PEX group (without phacodenesis and pupil >4mm) compared to controls. They observed significantly higher rates of PCO and increased incidence of cardiac illness in PEX group. She also emphasized on longer follow up needed in PEX group due to higher incidence of developing glaucoma with age.
Refractive and IOL issues in glaucoma patients
Dr. Coote discussed points one must remember while planning a cataract surgery in a patient with glaucoma. He said it is important to rule out other ocular pathologies, which may be attributing to loss of vision. He suggested that cataract surgery should preferably be done before or with glaucoma surgery and not after. He advocated use of hydrophobic and toric (when needed) IOLs and condemned the use of hydrophilic and multifocal IOLs in glaucoma patients. He cautioned against possible intraoperative (poorly dilating pupil, capsular instability) and postoperative (IOP spike, bleb failure) complications of cataract surgery in these patients.
What did we learn from the EAGLE trial?
Dr. Foster quoted studies to show how with increase in rates of cataract extraction and laser iridotomy, the incidence of acute primary angle closure has decreased significantly. He discussed in detail the design and results of EAGLE study. He showed that after 3 years, phaco clear lens extraction resulted in better quality of life, lower pressures on less medication and was more cost effective than laser PI. He concluded by saying that clear-lens extraction should be considered as an option for first-line treatment of PAC & PACG.
What is the added value of MIGS to phacoemulsification?
Dr. Kerr emphasized on benefits of combining MIGS with cataract surgery. He said the combination achieves lower intraocular pressures with fewer anti glaucoma medications, improves ocular surface disease and quality of life as well. It is also believed to reduce the rate of glaucoma progression and the total cost of treatment.
When is phaco alone the best procedure with open angles?
Dr. Jinapriya did an elaborate review of literature and suggested that higher the preoperative IOP, higher is the postoperative IOP reduction after cataract surgery. This IOP lowering effect was seen to last between 2-4years. He concluded by enumerating the scenarios where phaco alone is the best procedure in open angle glaucoma: medically controlled, preoperative IOP and postoperative target IOP in mid teens, optic nerve could sustain IOP spike after cataract surgery and compliance with medications is not a problem.
When is phaco trab the best procedure with open angles?
Dr. Costa compared the surgical options available for open angle glaucoma: Phaco alone/Phaco+MIGS/Phaco+Trab. He said while Phaco and MIGS bring about only a modest IOP reduction, Phaco+Trab may be preferred in cases with advanced glaucoma where target IOP is in low teens or the patient is non-compliant to anti-glaucoma medications.