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Non-DR Retinal Vascular Diseases
Published in Ching-Yu Cheng, Tien Yin Wong, Ophthalmic Epidemiology, 2022
Sobha Sivaprasad, Luke Nicholson, Shruti Chandra
The retina has a dual circulation with the branches of ophthalmic artery supplying the inner retina. Retinal arterial obstruction is a retinal vascular disorder caused secondary to a thrombotic or embolic occlusion of the arteries supplying the retina. It can be central, branch, cilioretinal, or ophthalmic artery obstruction depending on the anatomical location of occlusion. Retinal arterial obstructions cause visual loss that tends to be severe and permanent. In a central retinal artery occlusion (CRAO) the obstruction generally lies posterior to the lamina cribrosa, is usually not visible on ophthalmoscopy, and a third of the central artery occlusions tend to be embolic in nature. In comparison, branch retinal artery occlusions (BRAOs) are mostly embolic, with the obstruction seen in the branches of the central retinal artery after it emerges from the optic nerve head. The embolus is invariably visible on ophthalmoscopy. More proximal occlusions in the ophthalmic artery and even in the internal carotid artery may also lead to visual symptoms; however the symptoms are more chronic in nature. An essential feature to be kept in mind when dealing with retinal arterial obstruction is their frequent association with systemic abnormalities and the need for detailed systemic evaluation.
Anatomy of the head and neck
Published in Helen Whitwell, Christopher Milroy, Daniel du Plessis, Forensic Neuropathology, 2021
The internal carotid artery has no branches within the neck and ascends deep to the styloid process of the skull and adjacent muscles, to enter the carotid canal of the petrous temporal bone. This canal passes forwards and medially to enter the internal cavity of the skull as the foramen lacerum. The internal carotid artery is now located to the lateral side of the sphenoid bone, enclosed within the cavernous sinus. Its path now proceeds anteriorly within the sinus and then it passes out of the sinus upwards to lie adjacent to the anterior clinoid process, where it enters the subarachnoid space by piercing the dura mater. This path is clearly seen on suitable radiographs and is known as the carotid siphon. At this point, the artery gives a branch called the ophthalmic artery, which passes through into the orbit, supplying the retina via the central artery of the retina and branches to the lacrimal gland and adjacent orbital structures.
Facial Layers
Published in Ali Pirayesh, Dario Bertossi, Izolda Heydenrych, Aesthetic Facial Anatomy Essentials for Injections, 2020
Eqram Rahman, Yves Saban, Giovanni Botti, Stan Monstrey, Shirong Li, Ali Pirayesh
The ophthalmic artery is the major artery supplying the orbit. Originating from the internal carotid artery in the middle cranial fossa, this artery traverses the optic foramen and subdivides into numerous branches inside the orbital cavity [7].
Imaging-based Assessment of Choriocapillaris: A Comprehensive Review
Published in Seminars in Ophthalmology, 2023
Rohan Bir Singh, Tatiana Perepelkina, Ilaria Testi, Benjamin K. Young, Tuba Mirza, Alessandro Invernizzi, Jyotirmay Biswas, Aniruddha Agarwal
The arterial blood supply to the choroid predominantly arises from the ophthalmic artery branches from the internal carotid artery.19 The ophthalmic artery branches into two posterior ciliary arteries (in 48% of eyes) or three posterior ciliary arteries (in 38% of eyes). The posterior ciliary branches into the medial and lateral posterior ciliary arteries, showing different anatomical variations. The long posterior ciliary arteries arise from the medial and lateral posterior ciliary arteries, whereas the short posterior ciliary arteries arise from other branches of the posterior ciliary arteries. These branches are further divided into choroidal arterioles, which ultimately branch and segmentally feed into the choriocapillaris lobule.17 The recurrent branches of the long posterior and anterior ciliary artery supply the anterior choriocapillaris, and the short posterior ciliary arteries primarily supply the posterior choriocapillaris.
Giant cell arteritis
Published in Postgraduate Medicine, 2023
The most serious complication of GCA remains permanent visual loss which can occur in up to 20% of patients before glucocorticoid therapy initiation [66]. In a study of patients with biopsy-proven GCA, patients with ocular involvement were older, with a lower ESR and were less likely to have a headache or other systemic symptoms of giant cell arteritis than those without ocular involvement [67]. Two proposed reason for this variability in ocular involvement are the lack of classic symptoms of GCA making patients less likely to be referred for temporal artery biopsy and treatment in a prompt fashion and that those with a highly inflammatory response (elevated inflammatory indices) had more circulating IL-6 which has angiogenic properties and could counteract the arteritic ischemia of GCA [66]. GCA has a predilection for the ophthalmic artery and its branches most importantly the posterior ciliary arteries and the central retinal artery. The posterior ciliary arteries perfuse the choroid which nourishes the photoreceptors in the outer third of the retina and the optic nerve head. The central retinal artery provides blood to the inner two third of the retina including the retinal ganglion cells – the axons forming the optic nerve. The ophthalmic artery in addition to these two branches, also provides blood to the extraocular muscles and the vasa nervorum of the ocular motor nerves [68]. Vision changes in GCA have been described as a result of each of these vessels, in addition, vessels in the vertebrobasilar circulation can become involved which supplies circulation to the occipital lobe.
A fungal epidemic amidst a viral pandemic: Risk factors for development of COVID-19 associated rhino-orbital-cerebral mucormycosis in India
Published in Orbit, 2023
Varshitha Hemanth Vasanthapuram, Roshmi Gupta, Namrata Adulkar, Akshay Gopinathan Nair, Renuka A Bradoo, Raghuraj Hegde, Usha Singh, Sameeksha Tadepalli, Bipasha Mukherjee, Saurabh Kamal, Md Shahid Alam, Raksha Rao, Sushma Ananthakrishna, Varsha Backiavathy, Ajay Krishna Murthy, Lynn D’Cunha, Gagan Dudeja, Annie Joji, Anjali Kiran, Kirti Koka, Moupia Goswami Mukhopadhyay, Sonam Poonam Nisar, Priyanka R. Rao, Chhaya A. Shinde
The mean duration of symptoms of CA-ROCM was 5.815 days (range 1–30, median: 5). Patients who presented early at an average of 4.3 days had a visual acuity better than 6/60 and those who presented later at a mean of 6.39 days had a visual acuity of 6/60 or worse (p = .0123, 95% CI −3.41 to −0.42). The most frequent clinical feature was blepharoptosis (84.74% 150/177) followed by ophthalmoplegia (82.85% 145/175), palatal eschar (66.72% 114/172), proptosis (65.53% 116/167), central retinal artery occlusion (43.11% 72/167) and nose bleed (28.11% 47/166). One patient had ophthalmic artery occlusion. Imaging (CT or MRI) was available in 174 cases at the time of presentation. Features suggestive of sinus disease was most common (98.84% 171/173) followed by orbital disease (84.88% 146/172). Intracranial extension based on imaging was seen 15.6% (27/173), cavernous sinus involvement in 14.61% (25/171) (Supplementary: Table s2).