ANTERIOR SEGMENT EXAMINATION TECHNIQUES

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1 ANTERIOR SEGMENT EXAMINATION TECHNIQUES GERS October 2017 Amanda Harding - Principal Optometrist, MREH MSc., MCOptom, Dip Glauc., Dip TP (IP).

2 Anterior Segment Examination Depth of anterior chamber Central Peripheral Angle examination Cells Pseudoexfoliation material Pigment dispersion signs Heterochromia Trauma e.g. angle recession, iridodialysis, iris defects, hyphaema

3 Van Herick et al. Peripheral angle assessment - qualitative Angle illumination 60 degrees from microscope on temporal side illuminating beam approx. perpendicular to the limbus Obtain thin corneal section Use 10x to 16x magnification Focus the slit beam just in from the limbus Temporal angle assessment most accurate Compare width of the cornea with the peripheral angle (black space)

4 Original van Herick grading scale Van Herick s grading Ratio of gap to limbal corneal section Risk of angle closure Grade 4 1:1 or greater than 1:1 Angle closure very unlikely Grade 3 1:2 Angle closure unlikely Grade 2 1:4 Angle closure possible Grade 1 < 1:4 Angle closure likely Grade 0 Closed, no black space visible Angle closure

5 Van Herick technique Grade 4 Grade 1

6 Van Herick technique

7 Redmond Smith (1979) Central angle assessment - quantitative Angle illumination 60 degrees from microscope on temporal side Obtain thin corneal section of about 1mm Turn beam through 90 degrees until it is horizontal Reduce height of beam (width in horizontal plane) Focus slit beam on the cornea Second out of focus slit beam is on the lens iris diaphragm Adjust height (width) until the beams of light just touch

8 Redmond Smith technique

9 Redmond Smith technique Use right eye piece for right eye measurement Use left eye piece for left eye measurement Measurement in mm measured on slit lamp Multiplied by a constant 1.4mm (based on geometry) Normal adults (Northern Europeans) 3.6mm females, 3.7mm males < 2mm considered shallow and angle likely to be at risk of closure

10 Useful references Investigative Techniques and Ocular Examination by Sandip DOSHI & William HARVEY Butterworth-Heinemann/Optician 2002

11 Gonioscopy - Why? More clinically reliable than Van Herrick assessment Essential part of glaucoma assessment Anterior chamber angle not normally visible because of total internal reflection Contact lens necessary to overcome total internal reflection

12 Gonioscopy lenses

13 Techniques of Gonioscopy 1 Direct gonioscopy - (Koeppe lens) Indirect gonioscopy - (Goldmann lens) Advanced Technique - indentation gonioscopy

14 Techniques of Gonioscopy 2 Anaesthetise cornea Plenty of anaesthetic required Position at slit lamp with eye level at canthal marker Slit lamp column at slight angle Slit lamp beam small & narrow - not to constrict pupil Contact fluid on lens - lubricant gel

15 Techniques of Gonioscopy 3 Patient looks up Inferior edge of lens brought into contact with inferior sclera Lens tilted forwards until complete contact with globe Patient looks straight ahead Seal formed between cornea and lens with contact fluid excluding air bubbles

16 Techniques of Gonioscopy 4 Angle viewed is 180 o away from mirror used Varying width of beam from broad to narrow highlights different features of the angle If angle structures obscured by iris: angle lens towards angle being examined or angle patients gaze towards examining mirror

17 Gonioscopy - Angle Structures Schwalbe s Line - opaque line the limit of Descemet's membrane Trabecular Meshwork -nonpigmented & pigmented Scleral Spur - anterior projection of sclera Ciliary Body - depends on the position of iris insertion

18 Normal Angle Structures

19 Closed angle on gonioscopy

20 Identify the corneal wedge - Schwalbe s line

21 Gonioscopy Grading Systems 1 - Schaffer Grade 4 - (35-45 o ) ciliary body visible Grade 3 - (20-35 o ) scleral spur visible Grade 2 - (20 o ) pigmented trabeculum visible Grade 1 - (10 o ) Schwalbe s line visible Grade 0 - (0 o )

22 Gonioscopy grading Systems 2 - Spaeth Angular approach degrees Curvature of peripheral iris regular/steep/queer Position of iris insertion above or below Schwalbe's, scleral spur, deep

23 Indentation gonioscopy Dynamic examination Used in closed or occludable angles Distinguishes between appositional closure and Peripheral Anterior Synechiae (PAS)

24 Folds caused by indentation

25 Peripheral Anterior Synechiae (PAS)

26 Normal Iris Processes

27 Additional Gonioscopy Features Hyperpigmentation - PDS, PXF old age Sampolesi line - Pseudoexfoliation Peripheral Anterior Synechiae - Uveitis, chronic angle closure Angle Recession - Trauma Foreign body Trabeculectomy ostium

28 Iridodialysis

29 Ciliary Body Tumour

30 Primary Angle Closure Classification Primary Angle Closure Suspect (PACS) Narrow angles with irido-trabecular contact (ITC) without other pathology Primary Angle Closure (PAC) ITC with peripheral anterior synechiae (PAS) and/or raised IOP Primary Angle Closure Glaucoma The above with glaucomatous disc and field change

31 When to do laser peripheral iridotomy? When there is irido-trabecular contact > 180/270 degrees With or without increased IOP Symptoms/ PAS determine speed of treatment

32 Gonioscopy useful resources A fantastic resource with videos of gonioscopy Colour atlas of gonioscopy by Alward & Finkel

33 Pigment Dispersion Syndrome

34 Pigment Dispersion Syndrome - Signs Iris transillumination in the mid-periphery must dim room lights Krukenberg Spindle pigment deposits on endothelium following aqueous currents

35 Pigment Dispersion Syndrome - signs Very deep A/C Cause open-angle glaucoma Iris bowing concave Increased pigmentation of trabecular meshwork Scheie s stripe at lens edge only if v dilated

36 PDS - Epidemiology Males > Females Myopic Caucasian Often seen in CL exam Cause pressure spikes Exercise Can be aggressive open angle glaucoma

37 Pseudoexfoliation

38 Pseudoexfoliation

39 Pseudoexfoliation Signs Exfoliation material at pupil margin and on lens surface often clear zone seen where pupil margin Pigment in anterior chamber on iris/angle/cornea Gonioscopy brown granular pigment: Sampaolesi s line

40 Pseudoexfoliation More prevalent in elderly females Bilateral in 75% cases but often asymmetric Increased incidence in Scandinavian populaitons Can cause open and closed angle glaucoma Weakness of iris zonules Makes cataract surgery more tricky Often dilate poorly Prone to IOP spikes PXF can be present without glaucoma

41 Uveitis Ciliary injection Flare Cells Keratic precipitates Posterior synechiae Iris transillumination (Herpes Zoster) Can cause secondary open and closed angle glaucoma

42 Fuchs Heterochromic cyclitis

43 Fuchs Heterochromic Cyclitis Iris heterochromia Stellate KPs without flare and cells Some mild inflammation PSC Neovasc angle/iris

44 Rubeosis Rubeosis iridis due to neovascular stimulus secondary to ischaemia of retina Diabetic retinopathy Central retinal vein occlusion

45 Anterior segment dysgenesis - congenital Posterior embryotoxon: Axenfeld s (anterior displaced Schwalbe s line) ~ 8-15% population

46 Axenfeld-Rieger s Gonioscopy: tissue bridges across angle Iris atrophy, corectopia, ectropian uveae Systemic anomalies : teeth

47 Iris bombe with an A/C IOL

48 CASE MANAGEMENT 1

49 Presentation New referral to MREH triaged to New OLGA Optometrist referral not GERS Female aged 85 years old VA 6/9 R & L IOP (NCT) R 22 L 23 mmhg No comment on fields No comment on discs Noted to have van Herick Grade 2 R & L Routine referral due to IOP and angles Would you refer/do you think referral appropriate at this point? Discuss

50 New OLGA examination Unable to do fields it was attempted VA LogMAR R & L GH & History attended with daughter who reported early Alzheimer s on Memantine BP medication (Amlodipine) No reported sight problems or concerns by patient or daughter No previous ocular history of note GAT R 18 L am CCT 560 microns R & L Anterior segment normal accept for van Herick Grade 1 R & L Gonioscopy PTM visible in just 180 degrees of angle in both eyes Lenses nuclear sclerosis + R & L Discs healthy with CDR 0.2 R & L, no other ocular pathology

51 Possible Management Monitor Peripheral iridotomies Cataract surgery Discuss

52 Our management Monitor yearly in OLGA (optometrist led clinic) as patient comfortable and asymptomatic Daughter warned of symptoms of possible angle closure or reduced VA due to cataract If IOP increase, angles become narrower or VA decrease refer for best interest case discussion for cataract surgery MREH has specific best interest clinic

53 CASE MANAGEMENT 2

54 Presentation New referral to MREH triaged to New OLGA Optometrist referral for narrow angles only Male aged 62 years old VA R 6/7.5- R, L 6/ DS Rx R&L IOP Pulsair R 15mmHg L 13mmHg No comment on fields No comment on discs Reported as being asymptomatic Noted to have van Herick Grade <1 R & L Routine referral due to angles only

55 New OLGA examination HFA 24-2 SITA Standard normal in both eyes VA LogMAR R & L GH & History Prostrate cancer since 2010 in remission but regular check ups Medication solifenacin, fexofenadine, chlorphenamine, omeprazole No ACG symptoms No previous ocular history of note GAT R 10 L CCT 570 microns R & L Lenses clear lenses Discs healthy with CDR 0.4 R & L, no other ocular pathology seen

56 Angle Examination Anterior segment normal accept for van Herick Grade 1 R & L Smith measurement R 1.5 x 1.4 = 2.1mm L 1.4 x 1.4 = 1.96mm Gonioscopy (modified Schaffer) R 0 temp, 1 inf & nasal, 2 sup L 0 temp, 1 for others PAS infer and pigment superior

57 Systemic Medication Solifenacin - muscarinic receptor antagonist Decrease urination problems from overactive bladder Fexofenadine - antihistamine Chlorphenamine - antihistamine Omeprazole - proton pump inhibitors

58 Management Diagnosis - PAC PAS and pigment L eye suspicious Listed for L YAG PI < 4/52 Listed for R YAG PI 6/52

59 Acknowledgements Fiona Spencer Robert Harper Patrick Gunn Greg Harding Photography

60 Thank You