Internal jugular vein phlebectasia (IJVP) is a saccular or fusiform dilation of the internal jugular vein without tortuosity. In human patients, it causes an asymptomatic intermittent unilateral swelling in the lower part of the neck. Although the diagnosis can be suggested based on the clinical features, confirmation by imaging techniques is necessary. This report describes the first reported case of IJVP in a one-year-old Warmblood horse. The horse was admitted with a large, soft intermittent swelling in the right jugular groove, especially when lowering the head. Ultrasound showed an enlarged vein (10 cm diameter) draining normally towards the heart. Furthermore, contrast-enhanced CT (CECT) revealed a large distention of the deep venous system on the right side of the neck. Due to uncertain future athletic performance and both the extent and the complexity of the venous dilation, surgical intervention was declined and the horse was subjected to euthanasia. Post-mortem dissection revealed a small right external jugular vein but a markedly dilated right internal jugular vein (10 cm diameter), which is normally absent in horses. Based on the imaging and necropsy findings, diagnosis of IJVP was made.

中文翻译：

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一岁温血种马颈内静脉静脉扩张症

颈内静脉静脉扩张症 (IJVP) 是一种无迂曲的颈内静脉囊状或梭形扩张。在人类患者中，它会导致颈部下部无症状的间歇性单侧肿胀。虽然可以根据临床特征提出诊断，但仍需要影像学技术确认。本报告描述了第一例在一岁温血马中报告的 IJVP 病例。这匹马的右颈沟出现大而柔软的间歇性肿胀，特别是在降低头部时。超声显示扩大的静脉（直径 10 厘米）正常流向心脏。此外，对比增强 CT (CECT) 显示颈部右侧深静脉系统大量扩张。由于未来运动表现的不确定性以及静脉扩张的范围和复杂性，手术干预被拒绝，马被安乐死。尸体解剖显示右侧颈外静脉很小，但右侧颈内静脉显着扩张（直径 10 厘米），这在马中通常不存在。根据影像学和尸检结果，诊断为 IJVP。