GLAUCOMA

Question 1

1. How posterior segment of the eye is entered through?
2. What are components of anterior chamber angle?
3. Glaucoma definition?
4. Two routes of aqueous humor drainage?

Answer 1

1. The posterior segment of the eye is entered through pars plana Incision 3 to 4mm behind the limbus.
2. Schwalbe’s line
   Trabecular meshwork
   Scleral spur
   Ant surface of ciliary body
3. Trabecular meshwork route 90%… pressure dependent
   Schlem canal➡️aqueous veins➡️Episcleral veins
   Uveoscleral route 10%… pressure independent
   Ciliary body surface➡️ Suprachoroidal space➡️ venous circulation of ciliary body,choroid and sclera

3.Raised intraocular pressure characterized by optic disc cupping and characteristic visual field changes.

Question 2

1. What are dx procedures for glaucoma?

2.Name two tonometers?

3.Different Grades of gonioscopy?

4. What are glaucomatous optic disc changes?
5. Types of retinal ganglionic cells?

Answer 2

1. Tonometry
   Gonioscopy
   Fundoscopy
   Perimetry
   OCT
   Pachymetry
2. Schiotz tonometer
   Goldmann applanation tonometer
3. Grade 4….widest angle
   All for ant angle structures are visible
   Grade 3
   Only ciliary body is not visible
   Grade 2
   Ciliary body and scleral spur not visible
   Grade 1
   Ciliary body,scleral spur and trabecular meshwork not visible.
   Only schwalbe’s line visible.
   Grade 0
   Nothing is visible.
4. 🎟️Nerve fibre layer defect…earliest change
   🎟️Neuroretinal rim changes its color from orange to pale
   🎟️Cup to disc ratio becomes greater than 0.7 and a difference of 0.2 bw two eyes is pathological.
   🎟️Nasalization of blood vessels on optic disc.
   🎟️Splinter hemorrhages
   🎟️Peripapillary atrophy

5.parvocellular ganglionic cells…detect colour and visual aquity
Magnocellular…detect flicker and motion
Koniocellular … transmit short blue wavelength
magnocellular and koniocellular are damaged earlier than parvocellular ones in glaucoma

Question 3

1. Glaucoma visual field defects appear when ____% of axons have been damaged!
2. Which type of glaucoma is the most common?
3. Sign and Symptoms of glaucoma?
4. Medical TTT of glaucoma?
5. Which drug is not used in secondary glaucoma?

Answer 3

1. 40%
2. Primary open angle glaucoma.
3. Painless slowly progressive loss of vision.
   Night blindness
   Raised IOP.
   Glaucomatous visual field defects. Optic disc changes
   Angle is open .
   Diurnal Fluctuations in IOP if greater than 8mm of Hg is diagnostic of glaucoma.
4. 🎟️PG analogues…
   latanoprost,bimatoprost
   🎟️B blockers
   🎟️Alpha agonist …apraclonidone
   🎟️CA inhibitors…dorzolamide
   🎟️Miotics…. pilocarpine
   🎟️Adrenergics… epinephrine, dipivefrine
5. Pilocarpine raises capillary permeability which caused further rise in IOP such as in neovascular glaucoma and Inflammatory glaucoma.

Question 4

Primary angle closure glaucoma stages?

Answer 4

A. PAC Suspect
Normal IOP
Gonioscopy shows grade 1 to 2.
Anterior chamber depth is less.
Positive provocative tests.
TTT…laser peripheral iridotomy
Iredectomy

Subacute angle closure glaucoma
Episodes of blurred vision,halos and mild pain caused by raised IOP.
Pupil dilation ➡️ Relative pupillary block➡️Rise in IOP
TTT… pilocarpine
Prophylactic peripheral iridotomy.

Acute primary angle closure glaucoma
Conjunctiva is red and congested
Hazy cornea
Pupil is mid dilated
Optic disc swelling
Goniosshows narrow angle
Decreased vision.
TTT… systemic acetazolamide to lower IOP less than 40mm Hg
Or IV Mannitol and glycerol
Pilocarpine is started when IOP falls below 40mm Hg.
For preventing future attacks we do laser iridotomy (when less than 50% of angle is closed)
Trabeculetomy (when more than 50% of angle is closed)

Chronic angle closure glaucoma
Persistently elevated IOP.
Anterior synechiae is formed .
Narrow angle
TTT…Anti glaucoma drugs
Laser iridotomy
Trabeculetomy

Absolute glaucoma
Painful/painless blind eye
IOP is raised
Ciliary congestion is there
optic disc shows optic atrophy.
TTT…anti glaucoma drugs
Retrobulbar alcohol injection
Cyclocryotherapy
Diode laser ablation
Enucleation

Question 5

What is the age of
1.True congenital glaucoma
2.primary infantile glaucoma
3.juvenile glaucoma

4. What is the triad of congenital glaucoma?
5. What is the TTT of congenital glaucoma?

Answer 5

1. IOP elevation occurs at birth
2. Occurs within 3 years of age
3. Bw 3 to 16 years of age
4. Lacrimation, photophosphorylation and blepharospasm occurs in congenital glaucoma. In addition corneal haze and bupthalmos (corneal diameter greater than 13mm)
   **Haab striae ** are healed breaks on Descemet’s membrane that appear as lines.

5.Treatment
Miotics are not used bcoz of congenital angle anomaly.
PG,Beta blockers and acetazolamide are used.

Goniotomy….done when cornea is clear.
A communication is made bw anterior chamber and Schlemm canal.
Trabeculotomy…done when cornea is hazy
trabeculectomy and at end artificial drainage shunt when above procedures fail.