AN EXAMPLE OF GLAUCOMA DETECTION IN INDIAN OPTOMETRY CLINIC

1. AN EXAMPLE OF GLAUCOMA DETECTION IN INDIAN OPTOMETRY CLINIC -Rajesh Wadhwa M.Optom B.Sc.Hons.(Ophth.Tech.)(AIIMS)B.Sc.Hons.(DU); FIACLE;PGDHRM

2. Thank you for educating us:It was just stated.. • Dr.Sudhamathi: • Glaucoma is a silent thief of sigh • Optoms can look for • VH grading • ACG more often In Hypermetropes • RubeosisIrides is a sign Rajesh Wadhwa

3. Thank you for educating us:It was just stated.. • Dr.Sood: • Loss due to glaucoma is irreversible • Classical symptoms of acute glaucoma are often missing • Talked about categories of high-risk patients • Important investigations are Tonometry, gonioscopy, document the state of optic disc & visual fields. • We primarily work towards lowering the IOP Rajesh Wadhwa

4. Glaucoma-India-Optometrist“link” • Without gonioscopy • With or Without a perimeter/OCT/ HRT • Is there a link ? • Yes ! Golden because of great out-reach at very low cost Rajesh Wadhwa

5. We found the link • We worked towards it • We succeeded in preventing several more eyes from blindness • What is the “Key to Success” Rajesh Wadhwa

6. Why did we look for the key to success: a confession • Way back in the year 2000 • We analyzed our available clinic data • Over 50,000 patients seen in 20 years (1979 to 1999 ) • Total positive glaucoma cases detected= • 6 Rajesh Wadhwa

7. Was that good enough?WHO score • Indian population has over 2% incidence of glaucoma • We should have detected at least 1000 positive glaucoma cases • We had missed many:Disheartening and added tothe feeling of guilt • Many clinics are making this mistake inadvertently all over the world Rajesh Wadhwa

8. This needed an immediate intervention: Identified the limitations How much is glaucoma detection dependent on these? Clinical attitude towards detection of glaucoma No tonometry Legislation Space & time Rajesh Wadhwa

9. How dependent is glaucoma detection on these? • Most important screening tests are: • IOP: for over a century • Optic Nerve head analysis • Visual fields • Need the trio together • Though today’s science is way beyond this--but doing this much can save several eyes (as it did for centuries). Rajesh Wadhwa 6

10. Why are we asking for trio together? • IOP: alone is not a stand alone indicator (over 40% of Px have normal IOP at the time of diagnosis) • Optic nerve cupping: it's common for some people to have optic nerve cups that are larger than “normal” • Visual fields: even the visual fields can change back and forth and can sometimes be influenced by medication. (may not be available) • We can add other details (to be discussed in later slides). 4 Rajesh Wadhwa

11. 2 instrumental limitations (1=Tonometry) • No S/L initially • Lack of space for Schiotz • Applanation after acquiringslit lamp • Sterilization of Appln. very difficult • Needs topical anesthetic. Rajesh Wadhwa 5

12. 2 instrumental limitations (2= gonioscopy) • Not practiced at optometry school • Also needs topical anaesthetic 2 Rajesh Wadhwa

13. With inward compulsion to save more eyesWe broke the barrier: tonometry & gonioscopy • Tonometry: We invested into an expensive non-contact tonometer • Gonioscopy: Fletcher in his book says:”The Van Hericks grading of peripheral AC depth is so accurate that I did not feel the need to learn the skills of gonioscopy” Rajesh Wadhwa

14. Limitation that remained was of “clinical attitude” • In routine-refraction, we became more attentive to following: • Symptoms • Family history • IOP assessment • Optic nerve head assessment • High-risk categories • Details……….(cont.). 7 Rajesh Wadhwa

15. Symptoms • Most often: Reported for routine refraction but rarely (On close probing) • Headache/ Eye-pain/Colored halos • Transient blackouts/ Heaviness in eyes • Nyctalopia • Frequent change of glasses . 5 Rajesh Wadhwa

16. Categories encouraged for tonometry: • Age above 40years • Diabetics /Hypertensives • Hypermetropes • Family history of glaucomaor Diabetes • H/o previous eye injury/ disease or surgery • Cataract / Iritis • Relevant drugs being taken (systemic/topical). 5 Rajesh Wadhwa

17. What tests do we perform in optometric set-up • VA assessment • Refraction • Cover-test • Direct ophthalmoscopy • S/L exam if needed • Tonometry (filter exists) • Among these what will hint towards “glaucoma suspect” ? . 7 Rajesh Wadhwa

18. Noteworthy findings that add to suspicion of glaucoma • Accepts for near an "Add" value higher than what usually corresponds with age • Frequent change in refractive error 2 Rajesh Wadhwa

19. Lens & Iris: • Lens intumescent intumescent cataract a mature cataract that progresses; the lens becomes swollen from the osmotic effect of degenerated lens protein, and this may lead to secondary angle closure (acute) glaucoma. Rajesh Wadhwa

20. Rubeosis iridis • (especially in diabetics) • New vessels appear on the iris.  When this occurs, careful inspection of the anterior chamber angle is essential, as growth of neovascularization in this location can obstruct aqueous fluid outflow and cause neovascular glaucoma. Rajesh Wadhwa

21. Peripheral anterior chamber depth: Eclipse test • Eclipse Test:Shadow of iris eclipses/ does not eclipse the other side . Rajesh Wadhwa

22. Peripheral anterior chamber depth:VH Grading • Van Herick's Grading under S/L • (Grade 1 is shallowest, Grade 4 is widest) Rajesh Wadhwa

23. Van Herick's Grading under S/L: • Corneal thickness:periph. AC ratio (60° illum. angle) • <1:1/4= Gr 1 • 1:1/4 = Gr 2 • 1:1/4 to 1:1/2= Gr 3 • = or > 1:1/2= Gr 4 Rajesh Wadhwa

24. Optic nerve head assessment Rajesh Wadhwa

25. ISNT criterion Oval disc S T N Round cup I Rajesh Wadhwa

26. A B Cup:Disc Ratio recorded in its widest axis • Diameter of Cupping can be =pallor or Cupping>Pallor • Pallor Ratio=Contour Ratio or not Rajesh Wadhwa

27. Considered as Glaucoma suspect • ISNT criterion not met • C:D ratio >/=0.5:1 • Interocular diff. of C:D=/>0.2 • IOP > 20mmHg • Interocular diff. Of IOP =>4mm Hg Rajesh Wadhwa

28. Other reasons for suspecting glaucoma • Cup: Oval along 6-12 o’clock axis • Asymmetry between discs of two eyes is present. • Asymmetry does occur normally but the possibility of pathological significance is there especially in the absence of marked axial anisometropia Rajesh Wadhwa

29. Other reasons for suspecting glaucoma • Site of cup: Superior/ Superior temporal/ Inferior/ Infero-temporal. • Inferior location of cup has higher index of suspicion due to the more frequent superior field defects seen in glaucoma • Focal disc damage: Pit near 6 o'clock Rajesh Wadhwa

30. Vessels Continuity: • The blood vessels do not appear continuous at the disc margin • Baring of circumlinear vessel • Splinter shaped hemorrhage on disc margin Rajesh Wadhwa

31. Other reasons for suspecting glaucoma • Vessels Pulsation: NO spontaneous arterial pulsation. • (A spontaneous arterial pulse is more likely to be seen if the IOP is high) 2 Rajesh Wadhwa

32. Basis of inference • All foregoing indicators are kept in mind for referral • Fields, WDT, diurnal variation, Gonioscopy ,OCT etc. are to be considered in suspected cases • Did we gain anything by doing all this?Results……. Rajesh Wadhwa

33. This is an amazingimprovement over our previous results6 in 20 years, 22 in 1 year Compared to previous 20 years Rajesh Wadhwa

34. …Just 3 minutes more

35. Limitation in statistics: • This is retrospective analysis • Population sample is from 1 clinic in north India • Extra charges were taken for this checkup (therefore filtered) • Actual incidence could be higher 4 Rajesh Wadhwa

36. Do we really need tonometry? • All said-and done, tonometery is important in detection of glaucoma • If an optometrist is permitted to use that one drop of topical anesthetic then many more eyes can be saved Rajesh Wadhwa

37. How clear is our knowledge about glaucoma • ONE EXTREME: elevated IOP is not glaucoma. Elevated IOP is only a risk factor and is not prognostic (no magic figure) • OTHER EXTREME: New research suggests that Glaucoma, what we know to be an ‘eye disease’, should instead be characterized as a neurologic disorder similar to what causes nerve cells in the brain to degenerate and die – like what occurs in Parkinson’s and Alzheimer’s diseases. The new research paradigm focuses on the damage that occurs in retinal ganglion cells (RGCs), which connect the eye to the brain through the optic nerve. Rajesh Wadhwa

38. Where do we stand • We have treatment “for” glaucoma • We do not have treatment “of” glaucoma Rajesh Wadhwa

39. Take home message • IOP measurement is important in detection of glaucoma • Optometrist is the first line of defense against blindness & optometrists are eagerly waiting for government’s permission to use diagnostic drugs like topical anesthetics to save more eyes. • Aspects other than IOP can also be indicators for “glaucoma suspect” • It is better to refer out one extra “glaucoma suspect” than one less Rajesh Wadhwa

40. Thank you! My contact: r_wadhwa@yahoo.com Let us plant a sapling of good practice today…. ..and enjoy the fruits tomorrow Rajesh Wadhwa