ICGA fluorescence can penetrate blood, fluid and retinal pigment epithelium to reveal underlying abnormalities of the inner choroidal vasculature and is essential for making a definitive diagnosis of PCV. |
Extremely motion sensitive, requiring a patient to fixate on precise point for several seconds. Patient compliance required, which is often difficult, particularly for older patients. |
Excellent visualisation within minutes, of the medium & large choroidal vessels.
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OCTA takes more time than structural scans and requires trade-offs in flow resolution, scan quality and speed.
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ICGA is beneficial in the differential diagnosis of PCV, Chronic CSC, and RAP.
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Limited field of view leading to a greater likelihood that lesions may be missed. |
ICGA has been shown to optimise detection of capillary macro aneurysms in longstanding diabetic macular edema (DME) or retinal vein occlusion (RVO). |
Failure to recognise OCTA Projection Artifact (blood vessels seem at erroneous location), may lead to inaccurate clinical assessment. |
A recent study demonstrated that late leakage in ICGA occurred in all RAP cases*. |
Image processing for OCTA can alter blood vessel appearance through egmentation defects, and image display software can lead to false impressions of vessel location and density |
Duration of ICGA procedure only 15 20mins, very quick analysis. |
The analysis of these images is time-consuming – may involve many hours of post hoc manual segmentation work, which may be difficult to accommodate during daily medical work routines.
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