Page 105 - NAME OF CONDITION: REFRACTIVE ERRORS

 Confocal scanning laser ophthalmoscopy.(HRT)
 Scanning laser polarimetry (GDx)
 Optical coherence tomography.

POAG is chronic progressive optic neuropathy that is bilateral and asymmetric in
presentation
 Evidence of Optic Nerve Head damage
 Optic disc and retinal nerve fiber layer damage
- Diffuse thinning, focal narrowing or notching of neuroretinal rim (NRR)
especially at inferior or superior poles
- Progressive thinning of NRR with increased cupping
- Diffuse or focal peripapillary nerve fiber layer defects especially at poles
- Peripapillary splinter hemorrhages
 Reliable and reproducible visual field abnormality
- Visual field defects corresponding to retinal nerve fiber layer damage
(nasal step, arcuate scotoma, paracentral scotoma)
- Adult onset (more than 18yrs of age)
- Elevated Intraocular pressure > 22 mm Hg in majority of cases on two
successive occasions
- Diagnosis of exclusion (to exclude pigment dispersion, pseudoexfoliation
and other secondary open angle glaucomas)
Severity of glaucoma:
 HAP Visual Field Severity Score (Based on visual field damage)
Criteria for early defect
 Mean deviation no worse than −6 dB
 On pattern deviation plot, _25% of points depressed below the 5%
level and _15% of points depressed below the 1% level
 No point within central 5° with sensitivity _15 dB
Criteria for moderate defect
 Mean deviation worse than −6 dB but no worse than −12 dB
 On pattern deviation plot, _50% of points depressed below the 5%
level and _25% of points depressed below the 1% level
 No point within central 5° with sensitivity _0 dB
 Only 1 hemifield containing a point with sensitivity _15 dB within 5° of
fixation
Criteria for severe defect
 Mean deviation worse than −12 dB
 On pattern deviation plot, _50% of points depressed below the 5%
level or _25% of points depressed below the 1% level
 Any point within central 5° with sensitivity _0 dB

 Both hemifields containing point(s) with sensitivity _15 dB within 5° of
fixation

b) Investigations:
 Pachymetry

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