OCANZ Quiz QUESTIONS WITH COMPLETE 100% VERIFIED SOLUTIONS 2024/2025, Exams of Nursing

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OCANZ Quiz QUESTIONS WITH

COMPLETE 100% VERIFIED

SOLUTIONS 2024/

How many Australians have diabetes? 1.7 million What % of diabetes is type 2? 90% 90% What is type 1 diabetes? Immune mediated destruction of B cells What is type 2 diabetes? B cell dysfunction and insulin resistance B cell dysfunction and insulin resistance Who is at risk of type 2 diabetes?

40, waistline >80cmF/>94cmM, south Asian or African descent, polycystic ovaries, gestational diabetes, mental illness medication How is type 2 diabetes diagnosed? Venous plasma glucose >11.1mmol/l, >7.0mmol/l fasting, HbA1c 48 mmol/mol (6.5%) Name diabetic meds types: Metformin, Thiazolidenediones (pioglitazone), suplhonylureas (gliclazide), meglitinides, DPP-4 inhibitors (sitagliptin), glucosidase inhibitors What is prevalence of DR after two decades? 100% type 1, 60% type 2 What are the consequences of microvascular occlusion in DR? Hypoxia - > IRMA and NV What are the consequences of microvascular leakage in DR? Haems, plasma leakage - > oedema and exudates Haems, plasma leakage - > oedema and exudates What is R1? Flame, dot haems, singular blot haem What is R2? CWS, exudates, IRMA, venous changes, x2 blot haems What is R3? NVD, NVW, Rubeosis iridis, pre-retinal haems What are the types of diabetic maculopathy? Focal, diffuse, ischaemic, mixed

What do you need to provide medicare treatment? A provider number Who is a green medicare card for? A permanent resident or citizen of Australia Whois a blue medicare card for? Someone waiting for permanent residence - a temporary medicare card What is a RHCA? A reciprocal health care agreement card for certified countries When can't medicare benefits be claimed? For dispensing and adjustments, rx copies, cosmetic surgery, refractive surgery, vocational tests or tests for sports, tests requested by an employer, driving license tests, when testing a spouse or dependant, post-op aftercare What is code 10905? Referred following examination 10910? Sight test for px < 65 10911? Sight test for px > 65 10912? Early test with significant change in visual function 10913? Early test with new signs or symptoms 10914? Early test progressive disorder 10915? Examination of diabetic px 10918? Second consultation 0921? CL consultation NOT VALID IF WEARING FOR COSMETIC, WORK, SOCIAL, SPORTING OR PSYCHOLOGICAL PURPOSES 10931 - 10933? Domiciliary 10940 and 10941? Visual fields testing 10942? Low Vision Assessment

10943?

Children's vision assessment aged 3- 14 10944? FB removal What is the standard for Australian / NZ sunglasses? AS/NZS 1067 What is the standard mark for welding protection? AS/NZS 1338. What is the standard mark for filters against UV? AS/NZS 1338. What is the standard mark for protection against IR radiation?

What is the minimum a px records should be kept for? 7 years or until the age of 25, whichever is the longest Which state quotes a minimum of 10 years? Western Australia What is the ocular marking HT? Heat tempered What is the ocular marking CT? Chemically tempered What letters would be on a medium impact device? I and F What letters would be on a high impact device? V and B What letter would be on an extra high impact device? A What letters would be on specs for molten metals or hot solids? M or 9 What are visual standards for cars and motorcycles? Uncorrected VA no worse than 6/12 better eye - license allowed if adequate correction with specs, Corrected VA no worse than 6/24. 110 degrees horizontally with 10 degrees above and below midline, scotoma within 20 degrees of fixation What are the visual standards for a HGV? Uncorrected VA is worse than 6/9 in better eye or 6/18 either eye - conditional license if correctable. Visual field 140 degrees within 10 degrees above and below the midline, no field loss/scotoma, hemianopia, quadrantanopia likely to impede driving What are the visual standards for a train driver?

Can't be worse than 6/9 in best eye, can't be worse than 6/18 either eye. No visual field defect, not monocular, normal colour vision, no diplopia What are the visual standards for an electrician? Adequate colour vision - anomalous colour vision may be acceptable, D15 test. What are category A conditions for firefighters? BCVA less than 6/9 binocularly, less than 6/18 either eye, uncorrected distance less than 6/ binocularly, BC NVA less than N5, visual fields less than 120 degrees in the horizontal field each eye, protan defect, significant deutan defect, retinal detachment, diplopia, night blindness, corneal scarring, monocular vision What are category B conditions for firefighters? Mild deutan defect, cataracts, progressive or recurring eye disease What are visual standards for the police? May need good colour vision and no refractive surgery - needs referring to specialist if either of these criteria met If an occupational patient fails ishihara what is the next step? Occupational lantern test What are the visual standards for the armed forces? MRV1, MRV2, MRV 3 What are the standards in MRV1? Unaided 6/12, aided 6/6, no greater than 6PD horizontal, 1PD vertical What are the standards for MRV2? Unaided 6/24, aided 6/9, rx - 1.00 to +2.25 no greater than 1DC, no greater than 6PD horizontal or 1PD vertical What are the standards for MVR3? Unaided 3/60 Aided 6/12, up to +/- 7.00D What are the standards for a pilot? 6/9 corrected, 6/6 or better when tested with both eyes, no greater than +/-5D, N5 with correction, N without correction What level of amblyopia is significant? 0.1 or more logMAR, greater than 1 line snellen, What is the expected VA of a 2 year old? 6/12-6/9 with Cardiff Cards or SG What is the expected VA of a 1 year old? 6/18 Cardiff/Keeler What is the expected VA of a 6 month old? 6/36-6/30 Keeler or Cardiff What is the expected VA of a 3 month old?

6/90-6/

When would you prescribe the full rx to a child? Reduced likelihood of emmotropisation children with Down Syndrome / Cerebal Palsy. Strabismus. Previous spec wear chance to adjust to rx. What is the equation for back vertex distance? Fc = F/(1-dF) What bifocal seg is best for myopes and why? D segs as induce less jump What bifocal seg is for hypermetropes and why? Round segs, less prismatic effect at near What sizes are D segs available in? 25 ,28,35,40, What size are R segs available in? 22,24,25,28,30,38,40, What is the equation for calculating inset? Mono distance CD - mono near CD What is the equation for calculating different sized round segs? D1-D2 = 2xdp/add What is slab off? Removes base down prism from the lower part of the more negative lens. Name 7 types of eye protection. Eyecup goggles, eyeshield, faceshield, safety clip ons, spectacle eye protector, wide vision goggle, wide vision spectacles What is the LTF of grade 0 tinted specs? 80%-100% What is the LTF of grade 1 tinted specs? 43%-80% What is the LTF of grade 2 tinted specs? 18%-43% What is the LTF of grade 3 tinted specs? 8% - 18% What is the formula for calculating true surface power? Ftrue = Fnom x (ntrue-1)/(nnom-1) What is n for nominal index on lens measure?

What are the different plate designs in an Ishihara test? Demonstration, Transformation, Vanishing, Hidden, Diagnostic

What can the D15 test be used for? Classifying type of a defect What is the purpose of 100 hue test? Classifying type and severity What is Sheard's criterion? Fusional reserve must be at least 2 x demand. Prism needed = 2/3(phoria) - 1/3(BO to blur) What is the 1:1 Rule? Base in recovery should be at least equal to the amount of esophoria, base out prism needed = (esophoria - BI recovery)/ What is Percival's rule? Comfort zone is in the middle third of the width of clear single vision, prism needed = 1/3(Greater of lateral range blur limit BI or BO) - 2/3(less of lateral range blur limit) When will patients adopt a face turn? Horizontal deviation In a left lateral rectus palsy what head turn would be expected and why? Head will be turned to the left which deviates the eyes to the right away from muscle weakness When will a px adopt an elevation or depression? In A or V patterns What is a base out prism test? 20 base out prism in front of one eye, other eye should shift to take up fixation then first eye take up compensatory movement. Which intermittent esotropias require surgery? Near, distance, cyclic, non specific How would you manage a constant esotropia with an accommodative element? Order full rx, treat amblyopia, surgery if cosmetically poor What is a consecutive esotropia? Eso in a px who initially had an exo as a result of surgical over correction often intentional What are the types of esophoria? Convergence excess, divergence weakness, non-specific What are the types of exophoria? Convergence weakness, divergence excess, non-specific List 5 ways accommodation can be defective. 1 - Presbyopia, 2 - Accommodative insufficiency, 3 - accommodative fatigue, 4 - accommodative inertia, 5

• accommodative paralysis What is the normal range of AC/A ratio? 3 - 5 What can cause a limitation of movement?

1. neurogenic, 2) mechanical 3) myogenic What muscles cause an A eso? LR and IO What muscles cause an A exo? IR and MR What causes V eso? SO What causes V exo? SR What muscles are affected by a IIIrd nerve palsy? Medial, inderior and superior recti, inferior oblique, sphincter pupillae, ciliary muscle, levator What muscle is affected by a IVth nerve palsy? Superior oblique What muscle is affected by a VIth nerve palsy? Lateral Recturs What is the most common congenital muscle palsy? 4th nerve What will be the appearance of a 4th palsy? Eye hypertropic and esotropic What is the hallmark of a convergence excess esophoria? Greater at near than distance What is the hallmark of divergence weakness esophoria? Greater at distance than near What is the hallmark of a convergence weakeness exo? Greater at near with convergence insufficiency What is the hallmark of divergence excess exo? Greater at distance than near What are typical fusional reserves for base out near fixation? 30 - 35D What are typical fusional reserves for base in near fixation? 12 - 14D What are typical fusional reserves for base out distance fixation? 20 - 25D What are typical fusional reserves for base in distance fixation? 6 - 8D What are typical fusional reserves for vertical base? 2 - 4D

How do you perform fusional reserves? Introduce prism gradually, record blur / break / recovery What are exercises to improve esophoria and what is the aim? Aim to improve negative relative convergence - stereograms, bar reading and fusional reserve exercises What are the exercises to improve exophoria and what is the aim? Aim to improce positive relative convergence with stereograms, fusional exercises What causes a high AC/A ratio? Accommodative esotropia What causes a low AC/A ration? More exotropic at near What is the relationship between Ks and corneal astigmatism? 0.1mm = 0.50 astigmatism What can be done to amend an RGP with high decentration? Reduce lens thickness, reduce total diameter, may have excessive amounts WTR astigmatism - back surface toric How can lens movement be increased? Increase BOZR, Decrease BOZD, Decrease TD A px presents with irritated lens, mucus and excessive lens movements as well as lens deposits, investigation shows papillae and follicles on both upper lids and superior corneal staining. What is the cause and management? CLIPC - Cease lens wear, change lens material to lower modulus and more frequent replacement plan, cold compress, reduce WT, improve hygiene, sodium cromglycate What is the management for neovascularisation? Reduce lens wear, cease lens wear for few days, stop EW, increase oxygen permeability, SiH, decrease mechanical stimulation What are successful rxs for OrthoKs?

• 1.00DS to - 4.50DS, up to - 1.50DC and possible up to - 6.00DS What are the 4 key features of an orthoK lens? Flat central zone, reverse curve zone, peripheral aspheric zone, bevel Describe a typical reverse geometry fit. Central touch, mid peripheral clearance, peripheral alignment, edge lift What should the ideal fitting profile of an ortho Ks be? 4 - 5mm diameter centrally flattened zone, concentric regular steep zone, peripheral cornea with unchanged geometry How is Horner's pupil diagnosed? 4% cocaine - no dilation with Horner's. Hydroxyamphetamine 1% preganglionic lesion both pupils will dilate, post ganglionic lesion the Horner's pupil won't dilate

What are causes of Horner's pupil? Brainstem disease, spinal cord tumour, Pancoast tumour, carotid and aortic aneurysms, neck lesions, cluster headaches, otitis media, cavernous sinus mass, nasopharyngeal tumour How is Adie's pupil diagnosed? Pilocarpine causes abnormal pupil to contract vigorously What is the appearance of Adie's pupil? Larger pupil initially and may be irregular, smaller over time 'Little Old Adie' What drops are often prescribed post cataract? Maxitrol - (dexamethasone, polymyxin, neomycin) and predforte !% What is the incidence of post-cat CMO? 1 - 2% What is the incidence of post-cat endophthalmitis? 0.1% What is the incidence of retinal detachment post-cat? 0.7-3.6% What is the incidence of raised IOP post-cats? 8% What % of men are deuteranomolous? 5% What is the incidence of PSCLO post-cats? 8% What are type 1 R-G defects? Associated with reduced VA and central field defect. Caused by cone and RPE dystrophies - Stargardts, Chloroquine dystrophy What are type 2 R-G defects? Acquired retinal ganglion cell disease, optic neuropathy What are type 3 defects? Blue-yellow, reduced sensitivity or peripheral field defects - rod dystrophies, retinal vascular disorders, peripheral retinal lesions, retinal nerve fibre defects, macula oedema, What are causes of Roth spots? Endocarditis, leukaemia, anaemia, anoxia, CO poisoning, hypertensive retinopathy, pre-eclampsia, diabetic retinopathy, neonatal birth trauma, shaken baby syndrome What are side effects of cocaine? ACG, reduced vision, CV defects, visual hallucinations, photosensitivity, reduced pupil reactions to light and mydriasis, paralysis of accommodation, exophthalmos, optic neuritis, madarosis, iritis, retinal haems, CRAO How is CMO treated?

CAI and steroids, ketorolac (NSAID) What are non-optometric treatment options for keratoconus? Keratoplasty (penetrating or deep lamellar), collagen cross linking What are the advantages and disadvantages of DALK? Advantages - no risk of endothelial rejection, less astigmatism and a structurally stronger, increased availability of graft material Disadvantages: difficult and time consuming, high risk of perforated cornea, interface haze What are the advantages and disadvantages of collagen cross linking? Can be used in early to moderate keratoconus, helps to prevent keratoconus worsening, side effects include: punctate keratitis, corneal epithelium defect, haziness, dry eye, photophobia What are the advantages and disadvantages of penetrating keratoplasty? Advantages: simpler technique, faster Disadvantages: higher rate of rejection.high astigmatism, more sutures, neovasc, longer visual rehabilitation What are the stages of treatment for a chemical injury? EMERGENCY: Irrigate eye for 15-30 minutes, double eversion of lids, debridement of necrotic areas of epithelium, MEDICAL TREATMENT: mild (grade 1 and 2) treated with short course of topical steroids, cycloplegic and prophylactic antibiotics for 7 days: steroids, ascorbic acid, citric acid, tetracyclines. SURGERY: Early surgery to revascularise limbus, Late surgery depend on damage What are the causes of diplopia in a blow out fracture? Haemorrhage and oedema, mechanical entrapment, direct injury to an extraocular muscle What are possible complications of blunt trauma? Corneal abrasion, acute corneal oedema, tears in Descemet's membrane, hyphaema, miosis, pigment imprinting, iridodialysis, ciliary shock, cataract, lens subluxation, lens dislocation, globe rupture, PVD, retinal detachment, choroidal rupture, commotion retina, optic neuropathy, optic nerve avulsion How is hyphaema treated? Tranexamic acid 25mg/kg t.i.d, mydriasis with atropine, monitor IOP How are foreign bodies managed? Removed with a sterile needle, magnetic removal for matellic bodies, a burr to treat rust rings, antibiotic, cycloplegie and ketorolac What medication can cause a vortex keratopathy? Hydroxychloroquine, amiodarone What are side effects of chlorpromazine? Granular deposits in the endothelium and deep stroma, lens capsule deposits, retinopathy What drugs can cause cataracts? Steroids, chlorpromazine, busulphan, gold, allopurinol What are the side effects of phenothiazines? Salt and pepper RPE disturbances, plaque like pigmentation and choriocapillaris

What medication can cause crystalline maculopathies? Tamoxifen, canthaxanthin, methoxyflurane, nitrofurantoin, nicotinic acid, interferon alpha, desferrioxamine mesylate, gentamicin What drugs are cause of optic neuropathy? Ethambutol, amiodarone, vigabatrin How is demyelinating optic neuritis treated? Intravenous methylprednisolone sodium succinate 1g daily for 3 days, oral prednisolone 1mg/kg/day for 11 days and tapered for 3 days, Intramuscular interferon beta-1a What is the presentation of NAION? Sudden painless loss of vision usually on waking, VA moderate to severe reduction, dyschromatopsia, visual field defect inferiorly, disc pallor What are predisposing factors for NAION? Hypertension, Diabetes, High cholesterol, sleep apnea, post cataract, use of Viagra What is the presentation of AION? Sudden profound unilateral visual loss, periocular pain, preceeded with visual obscuration, flashing lights. What is the treatment for AION? Intravenous methylprednisole sodium succinate 1g daily for 3 days and oral prednisolone 80mg daily, then reduced to 60mg, then 50mg. Maintenance at 10mg. What is the prognosis for CRVO? Non-ischaemic good prognosis, 50% return to near normal vision. Ischaemic is very poor due to macula damage. What is treatment for CRVO? Cannulation, IV triamcinolone for chronic macula oedema, optic nerve sheathotomy to decompress the central retinal vein. What are the three types of emboli and their appearance? Cholesterol - golden crystals usually at arteriolar bifurcations. Calcific - aorta or carotid artery plaques, white, non-scintillating close to the disc. Fibrin-platelet - dull grey elongated particles may fill lumen, associated with TIA. What medical investigation is required with patients with emboli? Pulse (to detect AF), blood pressure, carotid elevation, ECG, Blood - ESR and full blood count, fasting glucose, lipids In a BRAO would you expect hypo or hyper fluorescence of the affected area? Hypofluorescnce What is the prognosis of a CRAO? Very poor. What are the treatments options for CRAO? Ocular massage, anterior chamber paracentesis, intravenous acetazolamide.

What are differential diagnosis of retinal flecks: ARMD, Stargardt, Fundus Flavimaculatus, Alport Syndrome, Familial Dominant Drusen, Benign flecked retina What are the associations of CSR? Young, M>F, type A personality, stress, hypertension, alcohol, steroid use, lupus, organ transplantation, gastro-oesphagael reflux What are common causes of uveitis? Spondylitis, Psoriatic arthiritis, Juvenile arthiritis, rheumatid arthititis, ulcerative colitis, Crohn's disease, sarcoidosis, kidney disease, Behcet syndrome, VKH, toxoplasmosis, toxocariasis, CMV, HIV, Herpes simplex, congenital rubella, herpes varicella zoster, What are treatment options for uveitis? Mydriatics - tropicamide, cyclopentolate, phenylephrine, homatropine, atropine, topical steroids, periocular steroids, systemic steroids if non-responsive to topical treatment. Antimetabolites- methotrexate Immune modulators - cyclosporine (Behcet), Differentiate AAION and NAAION AAION and NAAION are very simular in there ocular presentations. ON involvment, haemorrhages, vessesl tortuous, RAPD AAION is often more sever symptoms NAAION associated with transient loss of vision AAION associated with GCA AAION accounts for 5-10% (10) of anterior ischemic optic neuropathies (AION) and is caused by inflammation and subsequent thrombosis of the short posterior ciliary arteries (SPCA's) Differentiate BRVO AND CRVO CRVO - thrombus of central retinal vein near lamina cribosa BRVO - thrombus at arterioveinous crossing point from atherosclerosis Risk Factors for CRVO? Hypertension, open angle glaucoma, diabetes mellitus Risk Factors for BRVO? Hypertension, cardiovascular disease, open angle glaucoma, and high body mass index (not diabetes mellitus What is often the presentation of BRVO CRVO?

variable degrees of intraretinal hemorrhage, cotton wool spots, macular edema, subretinal fluid, collateral vessels (chronic), iris and retinal neovascularization, dilated and tortuous veins, and ghost vessels. What are treatments for BRVO/CRVO, medical and surgical? Anti Veg F panretinal photocoagulation Describe how you would apply Sheards Criteroius Best for EXO Best for EXO patients The fusional reserve must be at least 2 times the demand Prism Needed = 2/3(Demand) - 1/3(Reserve) ex) @40cm = 10xp || BO: 12/20/ So Demand = 10 || Reserve = 12 Describe how you would apply the 1:1 rule? Best for ESO patients The base in recovery should be at least as great as the amount of the esophoria Base-Out Prism Needed = (Esophoria - BI Recovery) / 2 ex) @40cm = 12ep || BI: 12/18/ 12ep - 8 / 2 = 2BO needed What are fusional reserves? Fusional reserves - represents the horizontal vergence and vertical range required to overcome a heterophoria. Describe how you would apply percivals criterous 1/3 of the largest of BI BO reserves - 2/3 of the smallest Describe EBMD Anterior corneal disease causing RCE ( map-dot-fingerprint, Cogan's microcystic dystrophy, or anterior basement membrane dystrophy) FOH and LASIK are common risk factors Describe the difference between LASIK and LASEK LASIK stands for laser-assisted in-situ keratomileusis LASIK surgeon has cut a flap in it using either a laser or microkeratome

LASEK (laser epithelial keratomileusis) - trephine to make a cut in the epithelium which is then peeled back to expose the Bowman's layer of the cornea. Who would LASEK be more suitable for? People who may experience trauma (Boxer, fighter pilots) as it can be done again Who would LASIK be more suitable for? Higher Rx's and shorter recovery 3 types of laser surgery? Wavefront LASIK. Computer imaging provides the surgeon with a three dimensional map of the patients eye. This allows more accuracy with the procedure and a higher chance of the patient obtaining 20/2 0 vision post-operation. Standard LASIK. This involves reshaping the tissue of the cornea using a laser. Access to the cornea is obtained by cuttinga flap in the outer layer to allow the laser entry. Epi-LASIK. Here the surgeon cuts a thin layer from the cornea to allow him or her to reshape it using the laser. Sometimes the layer is replaced or it may be removed completely. The patient is provided with a soft contact lense to allow the cornea to heal unharmed. Describe Nafl permeates into the intercellular space associated with any epithelial cellular disruption. Wratten #12 yellow filter contact lens related - mechanical, exposure, metabolic, toxic, allergic and infections Describe Lissamine Green Lissamine green is an acidic, synthetically produced, organic dye that has been historically used in food products. Lissamine green stains dead and degenerate cells, yet does not stain healthy epithelial cells Describe Rose bengal stains dead and devitalized cells, as well as mucus, and should be observed using a white light source What is a normal amount of hyperopia for a 0-3 month year old? +2.00 D What is a normal amount of hyperopia for a 3-12 month year old? +1.38 D How much astigmatism do infants loose between 9-12 months? 2/ How much anisometropia may not cause amblyopia?

<2.00D

There less <50 % change of emetropisation if there is how much myopia at 3 months old?

Younger eyes usually show what type of astigamatism? WTR OLder eyes tend to show what type of astigmatism? ATR WTR has the steepest meridian horizontal or vertical? Vertical (- cyl @ 180) Hyperopic less likely to emetropise if there is what astigmatism? ATR How often should you review a newly prescribed young high hyperope? 4 - 6 weeks If >3.50 of hyperopia then how much you should you presribe (unless in school) 1.00 D less than lowest meridian If more than 2.50 astig how much should you prescribe? 1/ If < - 5.00 in first year how much should you undercorrect the child to allow for emetropisation? 2.00D If > 3.50 D and <1 year , how much shoudl you reduce Rx by? 1.00D If > 2.50 D in > 4 year old (pre school) you should correct by what

• 1.50D If > 1.50 D and in school correct how? Full If > 2.00 DC at 15 months you should? Reduce cyl by 1.50DC IF >2.00 DC at 2 years you should? Give partial if > 1.50D of cyl at 4 years you should? Give full Cyll If > 1D of oblique cyl you should? Correct 3/4 up to the age of 4, then correct full as oblique cyl is a risk factor for astigmatism How do you prescribe for a child with aphakia or pseudophakia? Over plus by 2-3 D to allow close world up until 2-3 years at which a bifocal would be appropiate Describe how to interpret the Ishihara

Fail 3 or 4 errors probable CVD ≥5 errors certain CVD Failure to see the red numeral indicates protan and failure to see the red-purple numeral indicates deuta Describe how you would interpret the Medmont C- 100 Average of 5 settings is minus (having failed the Ishihara test) Has a protan (red) deficiency. Distinguishes protan or deutan abnormal colour vision with high sensitivity and specificity. Test only those who have failed the Ishihara Medmont C100 should not be used to detect CVD or judge its severity. Describe how you would interpret the Farnsworth D Pass: no errors arranging the, colours, or only minor, transpositions or only 1 diametrical crossing. Fail: two or more diametrical crossings Categorises those with abnormal colour vision as either 'mild' or 'moderate/severe'. May differentiate protan, deutan and tritan defects. What is a Retinal Detachment? The separation of neurosensory retina (NSR) from the retinal pigment epithelium (RPE) by subretinal fluid (SRF)