1532hrs: Diabetic Retinopathy (Anthony Hall)

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1532_Hall

 

Huge range in prevalence of diabetes. The Masai women walking 10km or more per day to get water are not getting diabetes. Increasing urbanization of africa leading to rise in diabetes. Estimate 35% prevalence of retinopathy with most countries in Africa not having any laser. Free screening in Kilimanjaro yet still only 29% of DIABETICS had eye exam in previous year. Working to improve screening in different communities.

Laser training is needed. Residents in Nairobi learning, courses being given and innovation in the works. They are moving a laser between six different centres to deliver the care where it’s needed. What is the most dangerous component of the laser - the counter! Hung up on need to give 1500 burns but only about 260 burns on average actually are ones that take. Many patients therefore actually think they had adequate treatment. Better to give full and adequate treatment, even if leads to macular edema, then multiple under-treatments.

Gives case history, of young lady who had lost her vision more than one year prior to getting seen and was left with tractional retinal detachments. Other cases shown where patients have been seen too late considering they have known diabetes. 

Concludes talk showing a surgical video of patient with tractional retinal detachment. Talks about how the traction acts like a third hand so as long as cut upward, even if visualization not great, can cut upward.

abhall@kcco.net

 

1516hrs: Venous Occlusive Disease (David Albiani)

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Moved his talk to the end and skipped the pathophysiology in the interest of time. Quick run through of vascular conditions including malignant hypertension, ocular ischemia, etc. Classification based on ischmic or not and anatomic location. Then runs through some cases.

1516_Albiani

 

Case 1:

45 yo M, 6/120 vision with blood and thunder macula. Lots of blockage with late leakage on FA. Typical mountain on OCT. Ischemic.

Case 2:

41 yo M, less extensive heme, just a bit of leakage, milder macular edema. Non-ischemic.

Evaluation includes detailed eye exam, BP, glucose, HgA1C, etc

Complications can occur early or late.

Historically, much has been tried over many years. In past, COVS was basis of a lot of treatment and BVOS study. COVS suggested only treating ischemic and BVOS waiting 3 months for resolution before grid treatment.

Another historical failure was laser chorioretinal anastamosis. But kenalog and anti-VEGF began to appear.

Radial optic neurotomy, don’t do it! Published study 208.

Biggest advance was in 2009 with SCORE Reprot No 5. Intravtreal triamcinolone led to average 15 letter improvement on ETDRS chart.

Ozurdex also did an RCT comparing single Tx. Appearing in the April 2010 Ophthalmology.

CRUISE study looking at Lucentis for CRVO to observation in a RCT. Also did a sister study on BRVO. Both studies though excluded patients who had brisk afferent pupillary defects which may be a weakness of this study.

Another study looking at Avastin and grid laser combo, in Retina.

Study of VEFG Trap that Dr Albiani involved in showing 200X more biologic activity at 1 month post injection compared with Avastin. Presents a couple of case studies from this series. Bearing in mind potential bias as investigator cherry picking cases.

1500hrs: Age-related Macular Degeneration (Derek Godinho)

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Promises this to be a whirlwind tour in 15 minutes of macular degeneration. 

1500_Godinho

 

Incidence, prevention, and treatment of this condition. In developed countries, it’s the leading cause of irreversible legal blindness. A big problem that will increase as population increases.

Prevention: diet and vitamins

Treatment: Intravit Antif VEGF, Visudyne, steroids and variations thereof

Prevention

AREDS was the major study looking at prevention with Vits C, E beta-carotene, zinc and copper. AREDS-2 investigates dietary lipids omega-3 and lutein and zeaxanthin. Have also reduced Zn and omitting beta-carotene. Results expected in 2012.

Treatment

Anti VEGF: Macugen, Lucentis, Avantis

Macugen, although first out of the gate, isn’t used much as not proven to be effective.

Lucentis, penetrates all levels of the retina. A number of landmark studies related to this drug, such as the MARINA study. This is the study that showed an actual average gain of lines of vision. ANCHOR compared Lucentis to PDT and proved Lucentis to be better. FOCUS showed combination of Lucentis with PDT more effective than Lucentis alone.

Avastin, the full-length molecule, initially used systemically for GI carcinoma

Steroids, anti-inflammatory effect good, but high risk glaucoma from raising IOP

CATT Trail and others comparing the intravitreal drugs and await results.

Adverse event risk actually relatively low for the intravitreal injections.

PIER study looked at decreasing dosing by extending follow-up injections but found not good to delay the injections.

PrONTO study also looked at dosing.

SAILOR, EXCITE, SUSTAIN HORIZON all failed to maintain visual acuity, at least for lucentis, if less frequent than monthly (avastin is 6 wks).

Combination Therapy therefore looking to see if can prolong gap between visits

Combo as we know now is intravit Anti VEGF, PDT, Steroid. Benefits appears to be reduction in number/frequency of retreatments.

MONT BLANC and RADICAL studies looked at combination therapy

DENALI and EVEREST are current combo studies

Bottom line is that we will have more information on combination therapies; this is evolving.

Future treatments: VEGF-trap, Pazopaniib, Combrestastin, Bevasrianib, Complement inhibitors, PDGF inhibitors, Raditaion Thearpy, Alpha5beta-1 integrin agonists

Surgical treatments: subretinal removal of CNVM (not really being done)

Optical visual rehabilitation: cataract surgery does help these patients without worsening the macular degeneration, intraocular telescopic devices, low vision mag, vision training, and occupational training.