Journal of the Korean Society of Radiology (대한영상의학회지)

The Korean Society of Radiology (대한영상의학회)
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An Enlarged Perivascular Space: Clinical Relevance and the Role of Imaging in Aging and Neurologic Disorders

늘어난 혈관주위공간: 노화와 신경계질환에서의 임상적의의와 영상의 역할

  • Younghee Yim (Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine) ;
  • Won-Jin Moon (Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine)
  • 임영희 (중앙대학교 의과대학 중앙대병원 영상의학과) ;
  • 문원진 (건국대학교 의학전문대학원 건국대학교병원 영상의학과)
  • Received : 2022.04.11
  • Accepted : 2022.05.05
  • Published : 2022.05.01
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Abstract

The perivascular space (PVS) of the brain, also known as Virchow-Robin space, consists of cerebrospinal fluid and connective tissues bordered by astrocyte endfeet. The PVS, in a word, is the route over the arterioles, capillaries, and venules where the substances can move. Although the PVS was identified and described first in the literature approximately over 150 years ago, its importance has been highlighted recently after the function of the waste clearing system of the interstitial fluid and wastes was revealed. The PVS is known to be a microscopic structure detected using T2-weighted brain MRI as dot-like hyperintensity lesions when enlarged. Although until recently regarded as normal with no clinical consequence and ignored in many circumstances, several studies have argued the association of an enlarged PVS with neurodegenerative or other diseases. Many questions and unknown facts about this structure still exist; we can only assume that the normal PVS functions are crucial in keeping the brain healthy. In this review, we covered the history, anatomy, pathophysiology, and MRI findings of the PVS; finally, we briefly touched upon the recent trials to better visualize the PVS by providing a glimpse of the brain fluid dynamics and clinical importance of the PVS.

혈관주위공간(perivascular space; 이하 PVS)는 뇌 실질을 관통하는 세동맥 둘러싸고 있는 공간으로, 최근에는 별아교세포의 종족(astrocyte endfoot)에 의해 가장 바깥쪽이 경계지워지는, 체액, 세포, 결합조직으로 구성된 혈관벽내, 혈관벽 주위의 구획을 모두 아우르는 개념으로 이해하고 있다. 정상적으로는 현미경적 해부학 구조물이지만 이 구조물이 늘어나게 되면 MRI T1 혹은 T2 이미지에서 확인할 수 있게 된다. PVS의 명확한 실체나 임상적인 의의에 대해서는 아직 분명치 않은 부분이 많이 있지만 PVS의 확장(enlarged PVS; 이하 EPVS)은 다양한 퇴행성 뇌질환 뿐만 아니라 뇌출혈 및 외상성 뇌손상, 당뇨성 신질환 같은 다양한 질병과의 연관성이 있다는 연구 결과들이 발표되고 있다. 이번 종설에서는 PVS와 EPVS가 가지는 임상적 의의와 병태 생리에 대한 최근 문헌을 고찰하고, MRI를 이용한 정성적 평가 및 최적화에 대해 논의해 보고자 한다.

Keywords

Acknowledgement

This study was supported by the Korea Health Technology R&D Project through the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (Grant number HI21C0222).

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