Flu Angiography #2: Abnormalities

Abnormalities can either involve hypofluorescence or hyperfluorescence. Defects are sub-classified according to

• type of defect (leakage, blockage etc)
• Location (retina, choroid, optic nerve)
• depth
• whether in inner retina (sharp focus) or outer retina/choroid (blurred cos you're looking through retina)

Also timing of defect. Autoflu before injection can occur if there are drusen. Drusen fluoresce a bit even without NaF. Sclera and gliomas can too. Then you have early arterial filling defects, later arterio-venous leaks and late phase abnormal staining and leaks (lack of staining indicates non-perfusion).

HYPOFLU - FILLING DEFECTS

• Indicate not enough circ. Occlusion or insufficiency of artery/vein
• @Retina - central or branch occlusion of art/vein OR hypoflu showing optic nerve atrophy
• @ON - normally there's a bright flush @ arterial phase and venous phase & late staining. In cases of ON atrophy you get hypoflu and only late staining present. This could happen in glaucoma
• Choroidal

HYPOFLU - BLOCKED TRANSMISSION

• Retinal vessels not visible eg pre-retinal haemorrhage - blockage in media or anterior retina
• Choroidal vessels not visible indicates deep retinal/subret haemorrhage

HYPERFLU - ABNORMAL VESSELS

• Dilated and or tortuous, wide & bright
• Neovascular vessels - wide, leaky, high density
• Tumour Vessels
• Aneurysms/leaks

HYPERFLU - LEAKS

• Microaneurysms - initially contained, then hazy leaks. EG Background DR
• Inflammation causing leakage like ischaemic optic neuropathy
• Choroidal Pooling - breaks in the RPE and NaF pooling in subret space eg central serous retinop.

HYPERFLU - PRE-INJECTION FLU

• Autoflu - drusen
• Pseudoflu - not really fluorescing, just bright reflective surfaces - hard exudates, coloboma

HYPERFLU - TRANSMITTED FLU

• lack of pigment, retinal atrophy
• choroidal background brighter 'window defect'