Prospective Observation of Vascular Anastomoses Between the Retina and Choroid in Recurrent Toxoplasmosis

Retinal Angiomatous Proliferation in Age–related Macular Degeneration

“…4,6 Anastomotic connections between the retinal and choroidal circulation have been described in this subset of patients with neovascular ARMD. 4,6 A retinal choroidal anastomosis is known to occur in several different types of maculopathies, including infections with organisms such as toxoplasmosis, 13 photocoagulation, 14 trauma, 15 postradiation, 16,17 vaso- proliferative chorioretinal tumors, 18 idiopathic perifoveal telangiectasia, 19,20 and most prominently, neovascular ARMD. 1,2 Communications between proliferating retinal and choroidal vessels are extremely common in neovascular ARMD at the end stage of the disease or disciform scarring.…”

Anastomotic Vessels Remain Viable after Photodynamic Therapy in Primate Models of Choroidal Neovascularization

“…In previous work, investigators have demonstrated that it is not uncommon for more than one vascular direction (choroidal to retinal versus retinal to choroidal) as well as type (artery to vein, artery to artery, vein to vein) of anastomotic permutation to evolve. 11,19,32,51,52 Moreover, the larger-diameter anastomoses observed proximally may represent RCAs of retinal origin, rather than CRAs of choroidal origin. The enlarged diameters of the retinal feeder vessels and of certain proximal anastomoses suggest the possibility of a retinal arterial origin for these particular anastomoses, with colligation of these vessels and some of their smaller collateral tributaries within the FVT membrane.…”

“…A nastomotic vessels in the retina are commonly identified according to their presumed origin and termination points by terms that include chorioretinal (choroidal retinal) anastomoses (CRAs), which also can be labeled deep retinal vascular anomalous complexes [RVACs], 1,2 or alternatively, retinochoroidal (retinal choroidal) anastomoses (RCAs), which also can originate from retinal angiomatous proliferations (RAPs). 3 Regardless of their origin/termination or their flow direction, anastomoses occur as pathologic components of various retinopathic conditions that include age-related macular degeneration (AMD), 1,2,[3][4][5][6][7][8][9][10][11][12][13][14][15][16] proliferative diabetic retinopathy, 17 uveitis, 18 -22 congenital anomalies, 19,[23][24][25][26][27] idiopathic juxtafoveolar retinal telangiectasis, 28,29 idiopathic central retinal vein occlusion, 30 sickle cell disease, 31 histoplasmosis, 19 toxoplasmosis, 32 angioid streaks, 33 and physical trauma 34 -36 (for a general review, consult Kottow 37 ). CRAs in exudative age-related macular degeneration (AMD) with occult choroidal neovascularization (CNV) represent a serious clinical feature that appears to respond poorly to either photocoagulative therapy 1,10,22,38<...>…”

Chorioretinal Vascular Abnormalities Associated With Angioid Streaks and Pseudoxanthoma Elasticum

“…Various types of congenital and acquired vascular anastomoses involving the retina, the choroid, or both have been described previously. [17][18][19][20][21][22][23] Acquired retinoretinal arteriovenous communications are recognized manifestations of ischemic diseases such as diabetes, proliferative sickle cell retinopathy, and occlusive disease of the carotid artery. Following ischemic obstruction or destruction of physiologic vessels, these communications develop to allow blood to flow from obstructed arteries to patent veins.…”

“…Following ischemic obstruction or destruction of physiologic vessels, these communications develop to allow blood to flow from obstructed arteries to patent veins. 17 Acquired retinochoroidal arteriovenous communications have been described also in the late stages of age-related macular degeneration, 18 in vascularized retinal epithelial detachments in age-related macular degeneration, 19 in recurrent toxoplasmosis, 20 and subsequent to the development of disciform lesions secondary to traumatic choroidal ruptures. 21 These arteriovenous communications need to be differentiated from the opticociliary shunts that represent dilated venous collateral channels in cases of primary or secondary retinal venous obstruction.…”