Download - GLAUCOMA داء الزرقاء
GLAUCOMA LOOK OUT One of the leading causes of blindness
Visual loss is irreversible Early diagnosis and proper management
is important Not A Single Disease A group of disorders
characterized by:
A progressive optic neuropathy resulting in a characteristic
appearance of the optic disc, and a specific pattern of
irreversible visual field defects, that are associated frequently
but not invariably with raised IOP. {NTG ; OHT} Classification Open
Angle Glaucoma: A- Primary (POAG)
B- Secondary(SOAG) Angle Closure Glaucoma: A- Primary (PACG) B-
Secondary(SACG) 3. Congenital & Developmental Glaucoma: A-
Primary Congenital Glaucoma B- Developmental Glaucoma (with
associated anomalies) Pathogenesis of Glaucomatous Ocular
Damage
Retinal ganglion cell death with loss of retinal nerve fibers due
to: Raised IOP (mechanical theory) Pressure independent factors
(vascular insufficiency theory) Chronic glaucoma: what is
happening
Or poor blood supply here Either: the drain blocks here Damages the
optic nerve..looks caved in, called cupped POAG Chronic Simple
Glaucoma
Triad (Criteria of diagnosis) RISK FACTORS: Heredity. Age (5th-7th
decade) Race (Black) Myopia. Retinal disease e.g. RP, CRVO DM
Hypertension Central corneal thickness PATHOGENESIS OF IOP
RISE
Impaired aqueous flow after the level of the angle e.g. Trabecular
sclerosis. CLINICAL FAETURES SYMPTOMS : ASYMPTOMATIC UNTILL TOO
LATE
PERIODIC CHECK UP after middle age. Mild headache, eye ache,
frequent change of reading glasses, delayed dark adaptation. SIGNS
: Raised IOP: Normal value Diurnal variation NTG ,OHT
Tonometry: {Digital, Indentation,Applanation, pneumatic
tonometer,tonopen} Normal central corneal thickness: 545 550
u
Add or subtract 2.5 mmHg for each 50 u change in central corneal
thickness Glaucoma tonometry (pressure test) Signs (Cont.) 2. Optic
disc changes: Cupping ( normally up to 0.4)
Large Asymmetry Progressive Vertical Notching Pallor Splinter
hemorrhage Nerve fiber layer atrophy Marked cupping, nasal shift of
blood vessels and CRA pulsation. Glaucomatous optic atrophy
Glaucoma damage SIGNS (Cont.) 3. Specific Visual Field
Changes:(Perimetry)
Initially observed in Bjerrum area (10 30 degrees from the fixation
point ) Small paracentral scotoma. Siedel scotoma (paracentral
scotoma join the blind spot to form a sickle shaped scotoma)
Arcuate scotoma (Siedel S. extend either above or below the
fixation point) Ring (double arcuate) scotoma. SIGNS (Cont.) 5.
Roenne central nasal step.
Roenne peripheral nasal step. Temporal wedge Tubular vision
Temporal island of vision. PERIMETRY HUMPHRY VFA FREDQUENCY
DOUBLING PERIMETER SHORT WAVE AUTOMATED PERIMETER (SWAP) GOLDMANN
PERIMETER SIGNS (Cont.) 4-. Wide open angle on Gonioscopy.
NB.
Slit lamp examination to rule out causes of SOAG. Documentation of
optic disc changes is very important. Recent tests e.g. Nerve fiber
layer analyzer (NFLA) Optical coherence tomography(OCT) MANAGEMENT
EVALUATION & ASSESSMENT TARGET PRESSURE TEHRAPEUTIC
CHOICE
MEDICAL ALT or DLT FILTRATION SURGERY MONITORING & FOLLOW UP
MEDICAL THERAPY TERATMENT IS ESSENTIALLY MEDICAL
TOPICAL DROPS (ORAL IS UNSUITABLE FOR LONG TERM TREATMENT) SINGLE
OR COMBINATION Aim is to lower IOP Decrease aqueous production
Increase aqueous drainage. MEDICAL (Cont.) Topical beta blockers:
decrease Aq. production
Timolol maleate (0.25, 0.5% BD) Betaxolol (0.25% BD) in asthma.
Levobunolol (0.25, 0.5% once daily) Carteolol (1% BD) low effect on
lipoprotiens . SE & Contraindications? Pilocarpine (1- -4%,
QDS): increase Aq. Outflow Ocular SE ? Systemic SE ? 3)Latanoprost
(PG F2alpha analogue 0.005%, once daily) Increase uveoscleral aq.
Outflow Expensive MEDICAL (Cont.) 4) Dorzolamide (2% TDS ,carbonic
anhydrase inhibitor), decrease Aq. Production 5) Adrenergic drugs:
Epinephrine hydrochloride & Dipivefrine hydrochloride ,
increase outflow. Brimonidine (0.2%, BD), decrease Aq. production.
ALT Laser shots at the ant. part of TM will lead to stretching of
adjacent area of TM Indication Failure of maximal tolerated medical
therapy. Non compliance to medical therapy Filtration surgery
TARBECULECTOMY
To create a fistula between AC & subconjunctival space thus
provide a new channel for Aq. outflow Indication: Failure of
medical & ALT Non compliance Non availability