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Gyrate Atrophy of the Choroid and Retina
Published in Charles Theisler, Adjuvant Medical Care, 2023
Gyrate atrophy is an inherited disorder of protein metabolism characterized by progressive vision loss. Individuals with this disorder have an ongoing loss of cells (atrophy) in the retina of the eye and in a nearby tissue layer called the choroid.1 Symptoms such as myopia, night blindness, and loss of peripheral vision develop during childhood. Over time, the field of vision progressively narrows, resulting in tunnel vision. These vision changes may lead to blindness by about the age of 50. Most patients with gyrate atrophy have no symptoms other than vision loss.2
Comparative Anatomy and Physiology of the Mammalian Eye
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
The main purpose of the choroid is to serve the retina. In some species, such as the rabbit, horse, guinea pig, and chinchilla, the retina is almost totally dependent on the choroid for nutrition since the retinal vessels are distributed to only a small area or are totally absent. In higher animals with holangiotic retinal vasculature, the choroid supplies nutrition to the level of the middle limiting membrane. These animals include humans, primates, dogs, cats, rats, and mice. The choroid is also responsible for the majority of the nutrition supplied to the fovea.117
Adult Ocular and Orbital (Ocular Adnexa) Tumors
Published in Pat Price, Karol Sikora, Treatment of Cancer, 2020
P.N. Plowman, Rachel Lewis, J.L. Hungerford
Hemangiomas affecting the choroid are of cavernous type, though their histology and clinical behavior are different from those of cavernous hemangiomas occurring at other sites. They are of two types—circumscribed or diffuse. Most are circumscribed and first detected in adult life. Circumscribed choroidal hemangiomas are not associated with systemic abnormalities. A minority of hemangiomas are diffuse. Diffuse hemangiomas commonly present in children and young adults and are usually associated with vascular abnormalities of the skin and CNS, often as part of the Sturge–Weber syndrome. Choroidal hemangiomas grow slowly, if at all. Nevertheless, they may threaten vision by producing a localized or extensive serous retinal detachment. Serous exudation may be reduced by argon laser grid photocoagulation with retinal reattachment, but usually without destruction of the tumor. If detachment persists or recurs, sustained retinal reattachment and good tumor regression may be achieved by irradiating a circumscribed choroidal hemangioma to a dose of only 40 Gy to the apex of the lesion, using a radioactive scleral plaque.
Choroidal Lymphoma: Diagnostic Value of Combined Indocyanine Green Angiography and Optical Coherence Tomography
Published in Ocular Immunology and Inflammation, 2023
Marco Pellegrini, Chiara Preziosa, Antonio Yaghy, Megan Ruben, Alessandro Invernizzi, Adrian T. Fung, Giovanni Staurenghi, Carol L. Shields
This particular incongruent imaging feature differs from what is observed in choroidal tumors and stromal choroiditis where there is a direct correlation between the area of involvement on OCT and the width of the lesion on ICGA. Choroidal metastases on EDI-OCT present an undulated inner choroidal contour with margins perfectly matching the area of ICGA hypofluorescence. Choroidal melanoma typically presents as a dome shaped configuration with inner choroid and choriocapillaris compression with tumor size corresponding to ICGA. Similarly, inflammatory lesions also demonstrate agreement between EDI-OCT findings and ICGA. Hypo-fluorescence deriving from choriocapillaris non-perfusion corresponds to typical loss of the dotted appearance of the choriocapillaris on EDI-OCT while choroidal granulomas appear as hypo-fluorescent areas on ICGA corresponding to homogeneous hypo-reflective lesions in the choroidal stroma with similar size on EDI-OCT21−23 (Figure 4).
Multimodal Imaging of Annular Choroidal Detachment in a Patient with Vogt–Koyanagi–Harada Disease
Published in Ocular Immunology and Inflammation, 2021
Jae Hyuck Kwak, Jiwon Baek, Ho Ra
Nonetheless, pathophysiologic mechanisms that can cause choroidal detachments in uveal effusion syndrome can be applied to explain the phenomenon in the current case. Vortex vein compression was suggested as a possible mechanism of uveal effusion in nanophthalmic eyes following glaucoma filtration surgery by Schaffer in 1975.6 Choroidal detachment in uveal effusion syndrome is considered to be caused by relative obstruction of venous outflow which may cause congestion of the choriocapillaris and alter the transmural hydrostatic pressure gradient, favoring increased retention of fluid in the suprachoroidal space. Choroidal detachment in the current case may be explained as follows. First, choroidal inflammation that causes hyperpermeability of choriocapillaris in VKH may allow extravasation of fluid and albumin to the extravascular space and eventually to suprachoroidal space.3 Second, vortex vein compression might lead to increased extravascular fluid retention and choroidal detachment. Many vortex ampullae were not observed in the UWF ICGA in the current case. Mechanical compression of the vortex veins by the adjacent thickened choroid might have caused choroidal outflow obstruction. This was evidenced by dilated choroidal veins in the UWF ICGA in the current case. Hasegawa et al.4 previously reported a VKH case with choroidal detachment, and their ICGA also revealed dilated choroidal veins at inferotemporal and inferonasal quadrant.
Management of inflammatory choroidal neovascular membranes
Published in Expert Review of Ophthalmology, 2021
Rachael Niederer, Asaf Bar, Haya Al-Ani, Lazha Sharief, Shaul Sar, Adi Segal, Sue Lightman, Oren Tomkins-Netzer
Choroidal neovascularization is a significant vision-threatening complication of pathologies that affect the retina and choroid. It is most commonly associated with elderly patients with age-related macular degeneration, though it can also appear in younger patients in relation to high myopia, angioid streaks, or conditions that result in retinal atrophy or scarring [3]. Among patients with uveitis, it can occur either as an early or late complication, mainly of posterior or panuveitis, with a prevalence ranging between 0.11 and 2% [4]. Due to the propensity of CNV to appear in the macular region, it may have a profound and lasting effect on patients’ lives for many years, particularly in bilateral cases [5]. Inflammatory CNV (iCNV) accounts for up to 6% of patients developing moderate or severe vision loss [6].