Central retinal artery occlusion crao fig initial stages

602

Fig.1: Severe NPDR- with ischemic
maculopathy. Extensive CNP areas are seen.
Hypofluorescence of non-perfusion areas is outlined by capillaries unlike hypofluorescence
because of blocked type. FAZ is grossly broken indicating severe macular ischemia.
iii) CNP areas (involvement of more than 5 disc diameter


v)	Dye usually stains and leaks from the venous wall in	i)	Active vasculitis- Narrowed vascular lumens.
late phases. Macula may show perifoveal capillary leakage (edema) or breakdown (broken FAZ i.e.
		ii)

9. Non-ischemic Central retinal venous occlusion (CRVO) - FFA advisable only after hemorrhages resolve significantly i.e. after 3-4 months.

i) Delayed central retinal venous filling (normally in 20- 25 seconds) and also delayed emptying.

ii) Engorged and tortuous retinal veins FFA picture depends on whether retina, choroid or

iii) Retinal hges (superficial) block both retinal & choroidal optic nerve is involved.

vii) Macula may show diffuse leaking from perifoveal

capillaries (may by cystoid with typically petalloid

ii) Extensive CNP areas all over the fundus.

ii) Cotton wool spots are seen as CNP areas (central hypofluorescence bordered by dilated capillaries).

	v)
iv) In older cases, extensive leakage from NVD or NVE		In disc edema because of malignant hypertension, no

13. Central Retinal Artery Occlusion (CRAO) (Fig.4)

characteristics. Retinal hemorrhages tend to be in mid		i)	In initial stages, poor choroidal flush (generalized
	561		February, 2006

sec)

(Box-carring) 17. Purtscher’s retinopathy-

edema and non filling. into vitreous. Blocked fluorescence

ii) Markedly delayed arm retinal may even mask the macroaneurysm.

vi) After about 2 weeks although dye is broken (Box-carring). involved segments.

flow starts in vessels but their

iii) Hypofluorescent areas also occur due to blocked

vii) In combined CRVO & CRAO, filling of arteries by dye

14. Branch retinal arterial occlusion (BRAO)-

Picture on FFA is similar to CRAO except that it is confined to the affected segment.

i) Hard drusen show as early hyperfluorescent dots increasing in AV phase but fading in later phases.

It includes Coats’ disease (multiple telangiectatic and	ii)
	ii)

iii) Focal hyperpigmentation and RPE atrophy- Mottled hyperfluorescence i.e. blocked background choroidal fluorescence interspersed with window defects.

i)	Telangiectatic and aneurysmal vessels are well made

iv) Vascular abnormalities as seen on FFA are much more than that seen on fundus examination.

16. Retinal arterial macroaneurysm-

� Early window defects

� Hypofluorescent areas due to choriocapillaris dropouts.

i) Classical CNVM- is well outlined even in early phases as hyperfluorescent patch of lacy pattern with increase in intensity and size in mid and later phases.

ii) Occult CNVM shows 2 patterns on FFA -

	562	DOS Times - Vol. 11, No. 8