QuizWise 16

1. All of the following are risk factors for the development of RAP except?
   a. Female gender
   b. Thin choroid
   c. Pseudodrusen
   d. Fellow eye affected by RAP
   e. Low dietary intake of vitamins A, C, D and E, and lutein and omega-3 fatty acids
   
2. Which of the following causes a RAP lesion?
   a. Neovascular AMD
   b. Trauma
   c. Postradiation
   d. Vaso-proliferative chorioretinal tumours
   e. Idiopathic perifoveal telangiectasia
   f. All of the above
   
3. Which of the following is the diagnostic feature of RAP?
   a. ICGA showing branching choroidal vessels
   b. ICGA showing  “hot spot” at PED center in intraretinal/subretinal layers
   c. OCT showing  subretinal or RPE lesions; drusen usually present
   d. FA showing subretinal  or sub RPE  leakage
   
4. Which of the following is not a stage of progression of RAP?
   a. Preretinal neovascularization
   b. Intraretinal neovascularization
   c. Subretinal neovascularization
   d. Choroidal neovascularization
   
5. All of the following are the differential diagnosis of RAP except?
   a. Diabetic macular edema
   b. Macular retinal vein occlusion
   c. PCV
   d. CNVM
   e. All of the above

Answers:-

1. e.
   Possible risk factors for a RAP lesion are

• Fellow eye affected by RAP
• Female gender
• Pseudodrusen
• Thin choroid
  Low dietary intake of vitamins A, C, E and E, and lutein and omega-3 fatty acids are the risk factors for development of CNVM

Reference: Tsai A, Cheung N.,  Gan A, Jaffe G., Sivaprasad S.,Wong T.,Gemmy Cheung C.: Retinal angiomatous proliferation. Survey of Ophthalmology 62  (2017)  462 -492. DOI: https://doi.org/10.1016/j.survophthal.2017.01.008

2. f.
Causes of RAP lesion are-

• Neovascular AMD
• Trauma
• Postradiation
• Vaso-proliferative chorioretinal tumours
• Idiopathic perifoveal telangiectasia
• Toxoplasmosis
• Photocoagulation

Reference: Yannuzzi L, , Negrão S, Iida T, Carvalho, Rodriguez–coleman H., Slakter J., Freund B., Sorenson J., Orlock D.: Retinal Angiomatous Proliferation In Age–related Macular Degeneration. RETINA 21:416–434, 2001. DOI: 10.1097/00006982-200110000-00003

3. b
Comparison of key characteristics between CNV, RAP, and PCV

	CNVM	RAP	PCV
FFA	Subretinal (classic) or sub-RPE (occult) leakage	Intraretinal/subretinal leakage with indistinct margins (i.e. minimally classic or occult pattern);  vascularized PED; vascular anastomosis, RPE tear	Branching choroidal vessels
ICG	Used mainly to identify RAP or PCV	“Hot spot” at PED center in intraretinal/subretinal layers	“Hot spot” at PED margin in choroidal layer; pulsatile polypoidal vessels
OCT	Subretinal or RPE lesions; drusen usually present	focal hyperreflective lesion (exudation) in intraretinal layers; intraretinal fluid subretinal fluid; PED common; drusen	Sub-RPE lesions; drusen usually absent

Reference: Tsai A, Cheung N.,  Gan A, Jaffe G., Sivaprasad S.,Wong T.,Gemmy Cheung C.: Retinal angiomatous proliferation. Survey of Ophthalmology 62  (2017)  462 -492. DOI: https://doi.org/10.1016/j.survophthal.2017.01.008

4. a.
Stages of progression of RAP  are categorized by the extent of retinal and choroidal involvement:-
Stage I- Intraretinal neovascularization
Stage II- Subretinal neovascularization
Stage III- Choroidal neovascularization

Reference: Bottoni F, Massacesi A, Cigada M, Viola F, Musicco I, Staurenghi G: Treatment of Retinal Angiomatous Proliferation in Age-Related Macular Degeneration. Arch Ophthalmol/Vol 123, Dec 2005.
DOI:10.1001/archopht.123.12.1644

5. e.
The differential diagnoses RAP include-

• Parafoveal telangiectasia
• Exudative maculopathy such as diabetic macula edema or macular branch retinal vein occlusion
• CNVM
• PED

Reference: Tsai A, Cheung N.,  Gan A, Jaffe G., Sivaprasad S.,Wong T.,Gemmy Cheung C.: Retinal angiomatous proliferation. Survey of Ophthalmology 62  (2017)  462 -492. DOI: https://doi.org/10.1016/j.survophthal.2017.01.008