Page 104 - NAME OF CONDITION: REFRACTIVE ERRORS

*Situation 2: At Super Specialty Facility in Metro location where higher-end technology is
available

a) Clinical Diagnosis: Comprehensive ophthalmic evaluation including
 History special attention to factors including systemic diseases that influence
diagnosis, course and treatment of POAG.
 Evaluation of visual function: with respect to difficulties in night driving, near vision
and outdoor mobility.
o Visual acuity measurement
o Pupil examination: to detect Relative afferent pupillary defect, which is a
function of optic nerve
o Anterior segment examination by Slit lamp biomicroscopy
o Intraocular pressure measurement by Goldmann applanation tonometry
o Gonioscopy:
 Is pre-requisite for diagnosis of glaucoma to rule out secondary causes
like angle closure, angle recession, pseudoexfoliation, pigment
dispersion, peripheral anterior synechiae, new vessels, blood in
schlemm’s canal and inflammatory precipitates.

 Optic nerve head and retinal nerve fiber evaluation by 90D stereopscopic
examination:
 Disc size.
 Neuroretinal rim
 Disc haemorrhage
 Nerve fiber layer defect.
 Peripapillary atrophy.
 Vascular pattern.
 Central corneal thickness measurement (CCT)
Thicker CCT overestimates IOP readings and thinner CCT underestimates. There is no
generally accepted correction formula. Thinner CCT is independent risk factor for
conversion of ocular hypertensive to POAG as proven in Ocular Hypertensive Treatment
Study.
 Visual field evaluation: characteristics of glaucomatous visual field defects
 Asymmetrical across horizontal midline.
 Located in midperiphery.(5-25 degrees from fixation).
 Reproducible.
 Not attributable to other pathology.
 Clustered in neighbouring test points.
 Defect should correlate with the ONH damage.

 Optic nerve head and retinal nerve fiber layer analysis

 Slit lamp indirect ophthalmoscopy using 90 D and 78 D lenses.
 Fundus diagrams.
 Stereoscopic disc photographs.

 Red free fundus photography.

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