Angle detection system for crossing compression of retinal artery and vein

Author(s):  
Chunping Liao ◽  
Xuefang Chen ◽  
Bifu Li ◽  
Xiaofang Zhao ◽  
Li Yu

The crossing compression of retinal artery and vein is closely related to retinal vein occlusion, so detecting the contraction angle of the crossed vein blood vessel can assist to diagnose the retinal vein occlusion diseases. Through pretreating methods such as filtering, enhancement and edge extraction, the binary edge images can be extracted. The candidate feature points can be obtained by the corner point detection method based on chord-to-point distance accumulation (CPDA). The self-adaptive rectangular filter is used to screen out the crossing point of candidate angle, so as to fit the edge curves and figure out the contraction degree of vein. The experimental results show that this algorithm can better detect the contraction degree of crossed vein blood vessel, with an average error remaining at ± 1∘ under different resolutions.

Author(s):  
Shivcharan Lal Chandravanshi, Sunil Kumar Shrivastava, Priyanka Agnihotri, Smriti Gupta

Aims and Objective - The aim of the present study is to identify risk factors associated with different retinal vascular occlusive diseases (RVOD), such as central retinal artery occlusion (CRAO), hemi-retinal artery occlusion (HRAO), branch retinal artery occlusion (BRAO), cilioretinal artery occlusion (Cilio-RAO), central retinal vein occlusion (CRVO), branch retinal vein occlusion (BRVO), and hemi-retinal vein occlusion (HRVO). Patients and Method - A cross-sectional study on 114 consecutive subjects, aged 24-96 years who have attended at the outpatient department of ophthalmology at Shyam Shah Medical College, Rewa, MP, were included in the study. The Duration of study was January 2016 to December 2017. Only patients with CRAO, BRAO, HRAO, Cilio-RAO, CRVO, BRVO, and HRVO were included in the study. Other retinal vascular disorders such as diabetic vaso-occlusive disease, anterior and posterior ischemic and non-ischemic neuropathy, hypertensive retinopathy, sickle cell retinopathy, retinal telangiectasia, retinopathy of prematurity, were excluded from study. Results - We have included 114 patients, 64 cases (56.14%) males, 50 (43.85%) females, aged 56+/-8 years (range 24-96 years).  Bilateral retinal vascular occlusive disorders were seen in only 4 cases (3.5%). Two patients have bilateral CRVO followed by one case of bilateral BRVO and one case of bilateral CRAO.  Out of 114 patients, branch retinal vein occlusion was seen in 62 cases (54.38%), followed by central retinal vein occlusion in 36 cases (31.57%), CRAO in 8 cases (7.01%), and hemi- retinal vein occlusion in 4 cases (3.50%). Hypertension was the most common, (40 cases, 35.08%) risk factor identified for retinal vascular occlusive disorders followed by diabetes 24 cases (21.05%), combined diabetes and hypertension in 22 cases (19.29%), and atherosclerosis in 18 cases (15.78%). Conclusions - Retinal vascular occlusive diseases have systemic as well as ocular risk factors. Understanding of these risk factors is essential for proper treatment of RVOD. Timely identification of risk factors for RVOD may helpful in decreasing ocular and systemic morbidity in these patients.


2020 ◽  
pp. 112067212090918
Author(s):  
Alessandro Arrigo ◽  
Karl Anders Knutsson ◽  
Firuzeh Rajabjan ◽  
Victor A Augustin ◽  
Francesco Bandello ◽  
...  

Purpose: To report a case of combined central retinal vein occlusion and branch retinal artery occlusion in a 51-year-old male with a very good response to dexamethasone implant therapy. Methods: This is a descriptive case report based on data from clinical records, patient observation and follow-ups, and analysis of acquired diagnostic tests. Results: A 51-year-old man presented with sudden vision loss and best-corrected visual acuity of 20/40 in his left eye. A pale inferotemporal arterial branch course area along with increased vascular tortuosity, retinal hemorrhages, optic disk swelling, and macular edema were observed on slit lamp biomicroscopy examination. Right eye was normal. Diagnosis of combined central retinal vein occlusion and branch retinal artery occlusion in left eye was confirmed by fluorescein angiography and color fundoscopy, respectively. Optical coherence tomography confirmed subretinal fluid and intraretinal cysts with a prominent middle-limiting membrane in the inner synaptic portion of the outer plexiform layer, corresponding to areas of paracentral acute middle maculopathy. Intravitreal dexamethasone implant was administered to the patient. One month later, visual acuity was recovered with complete absorption of macular edema. Functional and anatomical stabilization were confirmed after 24 months. Conclusion: Combined central retinal vein occlusion and branch retinal artery occlusion represents a rare condition, with variable functional outcomes due to the long-term complications such as macular edema. We hypothesize that prompt diagnosis and immediate intravitreal corticosteroid implant therapy reduced macular edema, thus contributing to arterial perfusion improvement, which in this case lead to a full sustainable recovery with limited functional and anatomical damage.


2019 ◽  
Vol 30 (3) ◽  
pp. 544-553
Author(s):  
Keiko MIWA ◽  
Daisuke MATSUMURA ◽  
Mei SUMIMOTO ◽  
Tomohiro KAWAHARA ◽  
Yasuhiro MORIIZUMI ◽  
...  

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