Retinal Vasculature and Imaging Techniques

<p>Prevent NaFl from invading the retina (A)</p> Signup and view all the answers

<p>NaFl appears in the central retinal artery within seconds. (C)</p> Signup and view all the answers

<p>Conditions affecting the circulation in the retina and RPE (D)</p> Signup and view all the answers

<p>It obscures fluorescein, leading to less fluorescence. (A)</p> Signup and view all the answers

<p>It enhances visualization of the borders associated with serous detachment. (B)</p> Signup and view all the answers

<p>It has poor image quality, making it hard to identify detailed capillaries. (B)</p> Signup and view all the answers

<p>Central Retinal Vein (D)</p> Signup and view all the answers

<p>Severe allergic reactions (B)</p> Signup and view all the answers

<p>Safety in pregnancy has not been established. (C)</p> Signup and view all the answers

<p>It may be used to accurately identify and ablate choroidal membranes. (D)</p> Signup and view all the answers

<p>Hyperfluorescence (B)</p> Signup and view all the answers

<p>It is a non-toxic dye for corneal endothelial cells (A)</p> Signup and view all the answers

<p>2% (B)</p> Signup and view all the answers

<p>ICG is primarily excreted by the liver (D)</p> Signup and view all the answers

<p>Geographic atrophy (B)</p> Signup and view all the answers

<p>Absorption and emission of infrared light (B)</p> Signup and view all the answers

<p>Allergy to iodine or shellfish (C)</p> Signup and view all the answers

<p>It retains most ICG in choroidal vessels (D)</p> Signup and view all the answers

<p>It can image through thin layers effectively (A)</p> Signup and view all the answers

<p>AV phase (C)</p> Signup and view all the answers

<p>To document disorders characterized by late leakage of dye (C)</p> Signup and view all the answers

<p>12 seconds (C)</p> Signup and view all the answers

<p>Ruptured blood vessels (A)</p> Signup and view all the answers

<p>Giving 50mg Promethazine before the injection (A)</p> Signup and view all the answers

<p>An emergency response system with defibrillators (B)</p> Signup and view all the answers

<p>Dye entering the choroidal circulation (B)</p> Signup and view all the answers

<p>Potential issues with dye injection or circulatory problems (C)</p> Signup and view all the answers

<p>Fluorescein angiography with barrier filters (D)</p> Signup and view all the answers

<p>To provide proper diagnostic clarity (B)</p> Signup and view all the answers

<p>Severe renal impairment (D)</p> Signup and view all the answers

<p>Capillaries and arteries are completely filled. (A)</p> Signup and view all the answers

<p>Venous Mid-Stage (B)</p> Signup and view all the answers

<p>Increased blood viscosity (B)</p> Signup and view all the answers

<p>Veins begin to empty while the arteries are still filled. (B)</p> Signup and view all the answers

<p>High concentration of RPE and xanthophyll. (C)</p> Signup and view all the answers

<p>Increased intensity due to a breakdown of barriers. (B)</p> Signup and view all the answers

<p>Increased fluorescein due to leakage. (D)</p> Signup and view all the answers

<p>Absence of retinal capillaries within a 500 micron space. (D)</p> Signup and view all the answers

<p>Early hyperfluorescence that fades without size change. (D)</p> Signup and view all the answers

<p>Prolonged retention of fluorescein. (A)</p> Signup and view all the answers

<p>ICGA is better for identifying borders in occult CNVM. (A)</p> Signup and view all the answers

<p>It requires an expensive imaging system. (A)</p> Signup and view all the answers

<p>Iodine sensitivity (D)</p> Signup and view all the answers

<p>Discoloration of urine (B)</p> Signup and view all the answers

<p>It remains protein bound and is rapidly metabolized by the liver. (D)</p> Signup and view all the answers

<p>Retinal capillary beds (B)</p> Signup and view all the answers

<p>Tight junctions (B)</p> Signup and view all the answers

<p>Fenestrated structure (B)</p> Signup and view all the answers

<p>Excitation of sodium fluorescein (B)</p> Signup and view all the answers

<p>It is metabolized into a fluorescent conjugate (B)</p> Signup and view all the answers

<p>RPE (D)</p> Signup and view all the answers

<p>Prevent NaFl from invading the retina (C)</p> Signup and view all the answers

<p>Arteries and capillaries are filled with fluorescein. (B)</p> Signup and view all the answers

<p>30 seconds (A)</p> Signup and view all the answers

<p>It appears as a dark spot due to high RPE concentration. (C)</p> Signup and view all the answers

<p>High blood viscosity (D)</p> Signup and view all the answers

<p>Arteries are completely empty, and veins are filled. (C), Dye is excreted by the kidneys. (D)</p> Signup and view all the answers

<p>Decreased or absent fluorescein due to optical obstruction. (A)</p> Signup and view all the answers

<p>Absence of the retinal pigment epithelium (RPE). (B)</p> Signup and view all the answers

<p>Central serous chorioretinopathy (CSCR) (D)</p> Signup and view all the answers

<p>It slowly diminishes after reaching maximum brightness. (B)</p> Signup and view all the answers

<p>ICG absorbs and emits light in the infrared range. (C)</p> Signup and view all the answers

<p>Late phase hyperfluorescence (C)</p> Signup and view all the answers

<p>ICG is not excreted effectively due to compromised liver function. (A)</p> Signup and view all the answers

<p>There is a loss of choriocapillaris perfusion. (C)</p> Signup and view all the answers

<p>They could develop a serious allergic reaction. (A)</p> Signup and view all the answers

<p>Albumin (B)</p> Signup and view all the answers

<p>Due to the impermeability of fenestration in choriocapillaris. (B)</p> Signup and view all the answers

<p>It can penetrate deeper than visible light due to infrared absorption. (C)</p> Signup and view all the answers

<p>To assess vascularity of the choroid. (B)</p> Signup and view all the answers

<p>Potential for renal impairment. (D)</p> Signup and view all the answers

<p>Approximately 12 seconds (C)</p> Signup and view all the answers

<p>Nausea (C)</p> Signup and view all the answers

<p>Choroidal circulation is filled (D)</p> Signup and view all the answers

<p>Potential circulatory problems (C)</p> Signup and view all the answers

<p>Mild allergies to food (A)</p> Signup and view all the answers

<p>The dye is injected into the antecubital vein. (A)</p> Signup and view all the answers

<p>Increased permeability in vasculature (C)</p> Signup and view all the answers

<p>It reduces the incidence of post-injection nausea. (C)</p> Signup and view all the answers

<p>Cystoid macular edema (A)</p> Signup and view all the answers

Blood vessels supplying the inner two-thirds of the retina. They have tight junctions, preventing leakage.

Blood vessels supplying the outer one-third of the retina, beneath the RPE. They have gaps (fenestrations), allowing substances like fluorescein to pass.

A layer of cells that forms a barrier between the choroid and the retina, preventing fluorescein from reaching the inner retina.

A technique using injected fluorescein dye to visualize blood flow in the retina and choroid. Used to diagnose eye diseases.

The artery supplying blood to the central retina.

Major retinal veins that drain blood from the retina.

Dye used in fluorescein angiography to visualize blood vessels.

The structures preventing leakage of substances from the blood vessels into the retina. Includes the retinal capillaries and RPE.

A diagnostic procedure using fluorescein dye to visualize the retinal and choroidal blood vessels.

The amount of fluorescein dye in a solution, usually measured in a percentage (e.g., 10% or 25%).

The antecubital vein (inside of elbow).

The time it takes for the dye to travel from the injection site to the retina, typically around 12 seconds.

A condition where a person has a severe allergic reaction to the dye or any components of the procedure.

The initial phase of the procedure when dye fills the choroidal circulation before reaching the retinal arteries.

The phase following the pre-arterial phase, where the dye reaches the retinal arteries.

A condition characterized by fluid buildup in the macular area of the retina, visualized with FAN.

Nausea, sometimes with vomiting.

To study and document eye disorders showing delayed dye leakage.

Complete filling of arteries and capillaries, showing retinal capillaries, especially around the optic nerve head and foveal avascular zone.

Subdivided into early, mid, and late stages of venous filling and arterial emptying during fluorescein angiography.

Increased fluorescence in an area, often caused by leakage, pooling, or transmission.

Decreased fluorescence, possibly caused by blockage, masking, or inadequate perfusion in certain areas.

Background choroidal fluorescence, visible around 10 seconds after fluorescein injection.

Area in the macula with no retinal capillaries.

A filtering layer that separates the choroid and the retinal pigment epithelium (RPE) that allows for the glow of the choroid to be seen partially.

Stage of fluorescein angiography where retinal veins start filling and arteries are still prominently visualized.

Abnormal new blood vessel growth in the choroid, causing leakage and hyperfluorescence.

Dense pigmentation of the retina causing hypofluorescence due to blockage of background choroidal fluorescence.

Indocyanine Green Angiography, a technique using Indocyanine Green dye to visualize blood flow in the retina and choroid. Used to diagnose eye diseases, particularly those affecting the choroid.

ICGA is particularly useful for identifying occult (hidden) Choroidal Neovascular Membranes (CNVM), especially those associated with serous detachment.

ICGA can be better than FAN (Fluorescein Angiography) for identifying CNVM borders, making it easier to determine the extent of the disease.

ICGA requires specialized and expensive imaging equipment, the quality of images can be poor, and detailed capillaries are difficult to visualize.

ICGA is generally considered safe with side effects similar to FAN, but severe allergic reactions have been reported in rare cases.

A condition where fluid builds up in the macula, causing swelling and blurry vision. It often happens due to inflammation or blockage of blood vessels.

CME shows up as hyperfluorescence in the late phase of the fluorescein angiography, indicating leakage of the dye into the swollen area.

A very serious type of eye cancer that can spread to other parts of the body if not treated promptly.

Geographic atrophy appears as a complete lack of fluorescence, signifying a loss of healthy retinal tissue.

A technique using a dye called ICG to visualize blood flow in the choroid, a layer beneath the retina.

ICG is preferentially bound to proteins, so it mainly stays in choroidal vessels, allowing for better visualization of choroidal blood flow.

Patients with liver disease, kidney problems, or allergy to iodine or shellfish must avoid ICG angiography as the dye is processed by these organs.

The small gaps (fenestrations) in the choriocapillaries allow small molecules to pass, but larger molecules like ICG are retained within the choroidal vessels.

ICG emits near-infrared light, which penetrates the retinal pigment epithelium (RPE) better than visible light, allowing for better viewing of choroidal structures.

Near-infrared light is scattered less than visible light, which improves the clarity of images obtained during ICG angiography.

A technique using fluorescein dye administered orally to visualize blood flow in the retina and choroid, particularly useful for studying disorders with late dye leakage.

The time it takes for the fluorescein dye to travel from the injection site to the retinal arteries, typically around 12 seconds in healthy individuals.

Common side effects of FAN include nausea, vomiting, allergic reactions, and temporary skin discoloration.

Conditions that make FAN unsafe, including hypersensitivity to ingredients, severe renal impairment, recent heart events, and pregnancy.

A condition characterized by fluid buildup in the macular region of the retina, causing blurry vision. It is visible as hyperfluorescence in late FAN.

The phase during fluorescein angiography where the injected dye reaches the retinal arteries, making them visible.

The final phase of fluorescein angiography, where the dye is gradually removed from the eye, allowing for the evaluation of leakage or dye retention.

A type of hyperfluorescence caused by a breakdown of the outer blood-retinal barrier, accumulating dye in the subretinal space.

Indocyanine Green Angiography (ICGA) is often preferred over Fluorescein Angiography (FAN) for detecting hidden Choroidal Neovascular Membranes (CNVM), especially those associated with serous detachment. This is because ICGA highlights choroidal blood flow, making it easier to visualize these lesions.

While ICGA offers advantages, it also has limitations. The imaging equipment is expensive, image quality might be poorer compared to FAN, and detailed capillary visualization is challenging.

ICGA is generally considered safe, with side effects similar to FAN. However, rare instances of severe allergic reactions have been reported. Common side effects include nausea and vomiting.

ICGA is particularly helpful for diagnosing occult CNVM, which are hidden beneath the retinal pigment epithelium (RPE). This is because ICGA's near-infrared light penetrates the RPE better than the visible light used in FAN.

Patients with iodine sensitivity or shellfish allergy, liver problems, and pregnant women should not undergo ICGA. The dye is processed by these organs, and its safety during pregnancy hasn't been established.

A build-up of fluorescein dye in a specific area of the retina, indicating leakage or fluid accumulation. This is often seen in conditions like cystoid macular edema.

Increased fluorescence in certain areas of the retina during the later stages of fluorescein angiography. This often indicates leakage of dye from blood vessels, signifying abnormalities.

A condition where the retina loses its function in a pattern that resembles a map, leading to permanent vision loss. This is due to the death of the tissue.

A complete absence of fluorescence in a particular area, suggesting a blockage of blood flow or lack of tissue in that region.

A diagnostic technique using Indocyanine Green dye to visualize the vasculature (blood vessels) of the choroid, the layer beneath the retina.

ICG dye is primarily excreted by the liver (80-90%), with a small portion excreted by the kidneys.

ICG is retained in the choroidal vessels due to its size, as the choriocapillaries have gaps that only allow smaller molecules to pass through.

ICG emits near-infrared light, which penetrates the RPE better than visible light, providing clearer images of deep choroidal structures.