branch retinal vein occlusion

網膜静脈分枝閉塞症 BRVO

WordNet

1. a part of a forked or branching shape; "he broke off one of the branches" (同)leg, ramification
2. divide into two or more branches so as to form a fork; "The road forks" (同)ramify, fork, furcate, separate
3. a division of a stem, or secondary stem arising from the main stem of a plant
4. a division of some larger or more complex organization; "a branch of Congress"; "botany is a branch of biology"; "the Germanic branch of Indo-European languages" (同)subdivision, arm
5. a stream or river connected to a larger one
6. make a veinlike pattern
7. any of the vascular bundles or ribs that form the branching framework of conducting and supporting tissues in a leaf or other plant organ (同)nervure
8. one of the horny ribs that stiffen and support the wing of an insect (同)nervure
9. a layer of ore between layers of rock (同)mineral vein
10. a blood vessel that carries blood from the capillaries toward the heart; "all veins except the pulmonary vein carry unaerated blood" (同)vena, venous blood vessel
11. a distinctive style or manner; "he continued in this vein for several minutes"
12. closure or blockage (as of a blood vessel)
13. (dentistry) the normal spatial relation of the teeth when the jaws are closed
14. broken husks of the seeds of cereal grains that are separated from the flour by sifting
15. food prepared from the husks of cereal grains
16. in or relating to the retina of the eye; "retinal cells"

PrepTutorEJDIC

1. 『枝』 / 『支流』,支脈,支線;分家 / 『支店』,『支部』,支局 / (学問の)『部門』,分科 / 枝を出す,枝を広げる / (川・道・鉄道などが)分岐する
2. 〈C〉『静脈』 / 〈C〉(植物の)葉脈;(昆虫の)翅脈;(石の)石理;(木の)木目 / 〈C〉岩脈,鉱脈 / 〈U〉《しばしば a vein》(…の)傾向,性質《+of+名》 / 〈U〉《the vein》(…に対する)気分,気持ち《+for+名(doing)》
3. ふすま,ぬか

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/02/08 09:18:05」(JST)

wiki en

[Wiki en表示]

Branch retinal vein occlusion

Branch retinal vein occlusion (BRVO) is a common retinal vascular disease of the elderly. It is caused by the occlusion of one of the branches of central retinal vein.

Epidemiology

• BRVO is 3 times more common than CRVO.

• Usual age of onset is 60–70 years.

• An analysis of population from several countries estimates that approximately 16 million people worldwide may have retinal vein occlusion.

Risk factors

Studies have identified the following abnormalities as risk factors for the development of BRVO:

• hypertension

• cardiovascular disease

• obesity

• glaucoma

Diabetes mellitus was not a major independent risk factor.

Manifestations

Patients with BRVO usually complain of sudden onset of blurred vision or a central visual field defect. The eye examination findings of acute BRVO include superficial hemorrhages, retinal edema, and often cotton-wool spots in a sector of retina drained by the affected vein.The obstructed vein is dilated and tortuous.

The quadrant most commonly affected is the superotemporal (63%).

Retinal neovascularization occurs in 20% of cases within the first 6–12 months of occlusion and depends on the area of retinal nonperfusion. Neovascularization is more likely to occur if more than five disc diameters of nonperfusion are present and vitreous hemorrhage can ensue.

Diagnosis and testing

The diagnosis of BRVO is made clinically by finding retinal hemorrhages in the distribution of an obstructed retinal vein.

• Fluorescein angiography is a helpful adjunct. Findings include delayed venous filling, hypofluorescence caused by hemorrhage and capillary nonperfusion, dilation and tortuosity of veins, leakage due to neovascularization and macular edema.

• Optical coherence tomography is an adjunctive test in BRVO. Macular edema is commonly seen in BRVO in OCT exams. Serial OCT is used as a rapid and noninvasive way of monitoring the macular edema.

Treatment

Several options exist for the treatment of BRVO. These treatments aim for the two of the most significant complications of BRVO, namely macular edema and neovascularization.

• Systemic treatment with oral Aspirin, subcutaneous Heparin, or intravenous thrombolysis have not been shown to be effective treatments for CRVO and for BRVO no reliable clinical trial has been published.

• Laser treatment of the macular area to reduce macular edema is indicated in patients who have 20/40 or worse vision and did not spontaneously improve for at least 3 months (to permit the maximum spontaneous resolution) after the development of the vein occlusion. It is typically administered with the argon laser and is focused on edematous retina within the arcades drained by the obstructed vein and avoiding the foveal avascular zone. Leaking microvascular abnormalities may be treated directly, but prominent collateral vessels should be avoided.

• The second indication of laser treatment is in case of neovascularization. Retinal photocoagulation is applied to the involved retina to cover the entire involved segment, extending from the arcade out to the periphery. Ischemia alone is not an indication for treatment provided that follow-up could be maintained.

• Preservative-free, nondispersive Triamcinolone acetonide in 1 or 4 mg dosage may be injected into the vitreous to treat macular edema but has complications including elevated intraocular pressure and development of cataract. Triamcinolone injection is shown to have similar effect on visual acuity when compared with standard care (Laser therapy), However, the rates of elevated intraocular pressure and cataract formation is much higher with the triamcinolone injection, especially the higher dosage. Intravitreal injection of Dexamethasone implant (Ozurdex; 700,350 μg) is being studied, its effect may last for 180 days. The injection may be repeated however with less pronounced effect. Although the implant was designed to cause less complications, pressure rise and cataract formation is noted with this treatment too.

• Anti-VEGF drugs such as Bevacizumab (Avastin; 1.25 -2.5 mg in 0.05ml) and Ranibizumab (lucentis) injections are being used and investigated. Intravitreal anti-VEGFs have a low incidence of adverse side effects compared with intravitreal corticosteroids, but are currently short acting requiring frequent injections. Anti-VEGF injection may be used for macular edema or neovascularization. The mechanism of action and duration of anti-VEGF effect on macular edema is currently unknown. The intraocular levels of VEGF are increased in eyes with macular edema secondary to BRVO and the elevated VEGF levels are correlated to the degree and severity of the areas of capillary nonperfusion and macular edema.

• Surgery is employed occasionally for longstanding vitreous hemorrhage and other serious complications such as epiretinal membrane and retinal detachment.

• Arteriovenous sheathotomy has been reported in small, uncontrolled series of patients with BRVO. BRVO typically occurs at arteriovenous crossings, where the artery and vein share a common adventitial sheath. In arteriovenous sheathotomy an incision is made in the adventitial sheath adjacent to the arteriovenous crossing and is extended along the membrane that holds the blood vessels in position to the point where they cross, the overlying artery is then separated from the vein.

Course and outcome

In general, BRVO has a good prognosis: after 1 year 50–60% of eyes have been reported to have a final VA of 20/40 or better even without any treatment. With time the dramatic picture of an acute BRVO becomes more subtle, hemorrhages fade so that the retina can look almost normal. Collateral vessels develop to help drain the affected area.

See also

• Central retinal vein occlusion
• Central retinal artery occlusion
• Branch retinal artery occlusion

References

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

• 1. 網膜静脈閉塞：疫学、臨床症状、および診断 retinal vein occlusion epidemiology clinical manifestations and diagnosis
• 2. 網膜静脈閉塞：治療 retinal vein occlusion treatment
• 3. 視覚変化が認められた小児患者に対するアプローチ approach to the pediatric patient with vision change
• 4. 全身性疾患および感染に関連した網膜血管炎 retinal vasculitis associated with systemic disorders and infections
• 5. イールズ病 eales disease

English Journal

• Retinal Vein Occlusion.

• Sawada O, Ohji M.
• Developments in ophthalmology.Dev Ophthalmol.2016;55:147-53. doi: 10.1159/000438971. Epub 2015 Oct 26.
• The primary treatment against macular edema with retinal vein occlusion (RVO) has changed from observation in central RVO (CRVO) and laser photocoagulation in branch RVO (BRVO) to administration of intravitreal agents based on anti-vascular endothelial growth factor (VEGF) or anti-inflammatory strat
• PMID 26501219

• Optical Coherence Tomography Angiography and En Face Optical Coherence Tomography Features of Paracentral Acute Middle Maculopathy.

• Sridhar J1, Shahlaee A1, Rahimy E1, Hong BK1, Khan MA1, Maguire JI1, Dunn JP1, Mehta S1, Ho AC2.
• American journal of ophthalmology.Am J Ophthalmol.2015 Dec;160(6):1259-1268.e2. doi: 10.1016/j.ajo.2015.09.016. Epub 2015 Sep 18.
• PURPOSE: To characterize the optical coherence tomography (OCT) angiography, en face OCT, and microperimetry features of paracentral acute middle maculopathy in both the acute phase and after resolution, and to propose a classification of distinct subtypes of this entity.DESIGN: Retrospective observ
• PMID 26386158

• Treatment of Retinal Vein Occlusion with Ranibizumab in Clinical Practice: Longer-Term Results and Predictive Factors of Functional Outcome.

• Farinha C1, Marques JP, Almeida E, Baltar A, Santos AR, Melo P, Costa M, Figueira J, Cachulo ML, Pires I, Silva R.
• Ophthalmic research.Ophthalmic Res.2015 Dec;55(1):10-8. doi: 10.1159/000440848. Epub 2015 Nov 6.
• PURPOSE: To evaluate long-term results and predictors of efficacy in patients with macular edema due to retinal vein occlusion (RVO) treated with intravitreal ranibizumab in a clinical practice setting.METHODS: The clinical records of patients with a minimum follow-up of 3 years were retrospectively
• PMID 26540281

Japanese Journal

• 臨床研究 黄斑浮腫を伴う網膜静脈分枝閉塞症の保存的治療における視力改善指標

• 日本眼科学会雑誌 121(2), 130-137, 2017-02
• NAID 40021103360

• 臨床報告 網膜中心静脈閉塞症に網膜動脈分枝閉塞症と硝子体出血を合併した1例

• 臨床眼科 70(13), 1925-1929, 2016-12
• NAID 40021016315

• 網膜静脈分枝閉塞症に伴う黄斑浮腫に対するトリアムシノロン・テノン囊下注射の治療成績 (第69回日本臨床眼科学会講演集(7))

• 臨床眼科 70(9), 1407-1411, 2016-09
• NAID 40020947998

Related Links

• What Is Branch Retinal Vein Occlusion (BRVO)? - American ...

Arteries and veins carry blood throughout your body, including your eyes. The eye’s retina has one main artery and one main vein. When branches of the retinal vein become blocked, it is called branch retinal vein ...

• Retinal Vein Occlusion: Causes, Symptoms & Diagnosis

There are two types of retinal veins. There’s one central vein and many smaller branch veins. Likewise, there are two types of retinal vein occlusion. There’s central retinal vein occlusion and branch retinal vein occlusion.

Related Pictures

---

★リンクテーブル★

リンク元	「網膜静脈閉塞症」「網膜静脈分枝閉塞症」「網膜静脈分枝閉塞」
関連記事	「occlusion」「branch」「retinal」「branched」「branching」

「網膜静脈閉塞症」

　　[★]

英

retinal vein occlusion, obstruction of the retinal vein

分類

• 網膜中心静脈閉塞症 central retinal vein occlusion CRVO
• 網膜静脈分枝閉塞症 branch retinal vein occlusion BRVO

リスクファクター

参考1

• 年齢、高血圧、糖尿病、喫煙、肥満、凝固亢進状態(factor V Leiden, activated protein C resistance)、緑内障、網膜細血管異常(retinal arteriolar abnormality)

出典不明

• 動脈硬化

比較

SOP.134

	網膜静脈分枝閉塞症	網膜中心静脈閉塞症	網膜中心動脈閉塞症
	BRVO	CRVO	CRAO
概念	網膜動静脈交差部で静脈が閉鎖	網膜中心静脈の閉塞	網膜中心動脈の閉塞
疫学	CRVOより遙かに頻度が高い	50歳以上の中高年で高血圧症のある人に好発	(1)血栓塞栓子、(2)乳頭内での粥状硬化、あるいは動脈炎による血管攣縮による動脈の閉塞、(3)緑内障や外力による高眼圧
病型		静脈うっ滞網膜症　venous stasis retinopathy：静脈拡張、出血など静脈閉塞のみを主症状とする。 出血性網膜症　hemorrhagic retinopathy：高度の血管床閉塞など動脈の循環障害を併発
症状	黄斑部を支配する静脈が閉塞すれば視力低下を痔核。	無痛性の片眼性の急激な視力低下	無痛性の高度視力障害
眼底	閉塞した静脈域で静脈の拡張し、透過性亢進による出血、浮腫、綿花白斑を生じる。数ヶ月の経過で出血は吸収され、静脈は白線化し、硬性白斑が残る。	視神経乳頭から放射状の火炎状出血、(重症例)暗赤色の出血斑。乳頭の充血、浮腫、網膜静脈の拡張蛇行、綿花様白斑、黄斑浮腫から嚢胞様黄斑浮腫	網膜は混濁、白濁。cherry-red spot
合併症	新生血管形成と硝子体出血。再発性硝子体出血と牽引性網膜剥離症(閉塞した静脈域の毛細血管の閉塞によりその領域周辺の網膜や視神経乳頭での血管新生をきたす)。	新生血管緑内障：予後不良。発症から3ヶ月が好発時期。前房隅角や虹彩に新生血管が生じ眼圧上昇をきたす。
治療	光凝固術：黄斑浮腫、新生血管に対して。 硝子体手術：硝子体手術、牽引性網膜剥離	原疾患の治療 新生血管緑内障予防：汎光凝固術	眼球圧迫マッサージ 亜硝酸アミル (高眼圧の場合)前房穿刺
予後			1時間以内に血行が改善しないと網膜機能の回復は期待できない。

参考

• 1. [charged] Retinal vein occlusion: Epidemiology, clinical manifestations, and diagnosis - uptodate [1]

「網膜静脈分枝閉塞症」

　　[★]

英

branch retinal vein occlusion BRVO

関

網膜静脈閉塞症、網膜静脈分枝閉塞

概念

• 網膜動静脈交差部で静脈が閉鎖

疫学

• 網膜静脈分枝閉塞症 CRVOより遙かに頻度が高い

症状

• 黄斑部を支配する静脈が閉塞すれば視力低下を痔核。

検査

• 眼底検査：閉塞した静脈域で静脈の拡張し、透過性亢進による出血、浮腫、綿花白斑を生じる。数ヶ月の経過で出血は吸収され、静脈は白線化し、硬性白斑が残る。

合併症

• 新生血管形成と硝子体出血。再発性硝子体出血と牽引性網膜剥離症(閉塞した静脈域の毛細血管の閉塞によりその領域周辺の網膜や視神経乳頭での血管新生をきたす)。

治療

• 光凝固術：黄斑浮腫、新生血管に対して。
• 硝子体手術：硝子体手術、牽引性網膜剥離

「網膜静脈分枝閉塞」

　　[★]

英

branch retinal vein occlusion

関

網膜静脈分枝閉塞症

「occlusion」

　　[★]

• n.

• 閉塞、閉鎖

関

occlude

関

atresia、close、closure、dental articulation、disturb、disturbance、hamper、hindrance、impede、impediment、intercept、interception、interfere、interrupt、interruption、obliteration、obstruct、obstruction、occlude、preclusion

　 　

「branch」

　　[★]

• n.

• 枝分れ、枝、分岐部、部門、ブランチ

• v.

• 枝分れする、分枝する

関

arbor、arborization、branched、branched chain、branching、class、department、division、ramification、ramus、section、sector

　 　 　 　 　 　

「retinal」

　　[★]

• 網膜の、(βカロチン誘導体の視物質アルデヒド帯)レチナール

関

11-cis-retinal、retina、retinae、retinaldehyde, retinol

　

「branched」

　　[★]

• adj.

• 分枝の

関

arbor、arborization、branch、branched chain、branching、ramification

　

「branching」

　　[★]

• n.

• 分岐、枝分かれ、分枝