줌렌즈, 초고속카메라 장착 세극등현미경으로 결막미세혈관 내 혈류 속도를 측정하는 새로운 방법 = Novel Method Measuring Conjunctival Microvascular Blood Flow Velocity by Zoom-lens, Ultra-high-speed Camera Attached Slit-lamp Biomicroscope

국문 초록 (Abstract)

목적: 줌렌즈와 초고속 카메라를 장착한 세극등현미경으로 구결막을 촬영해 결막미세혈관 내 혈류 속도를 측정하는 직관적인 방법을소개하고자 한다.
대상과 방법: 2020년 8월 21일부터 2021년 6월 12일까지 가톨릭의대 여의도성모병원에 내원한 총 10명을 대상으로 사전에 동의서를받은 후, 줌렌즈와 초고속 카메라를 장착한 세극등현미경으로 환자들의 구결막미세혈관 내 혈류를 녹화하였다. 이렇게 촬영된 영상을ImageJ 소프트웨어로 분석하여 결막미세혈관 내 혈류 속도를 측정하였으며, 혈류 속도가 혈관 직경, 나이와 상관관계를 보이는지알아보았다.
결과: 본 연구에 참여한 총 10명에서 피험자들 나이의 중앙값은 49.0세였다. 성별은 남자 1명, 여자 9명이었다. 53개의 미세혈관 내혈류 속도의 평균은 0.786 ± 0.468 mm/s였다. 53개 결막미세혈관의 직경의 중앙값(median)은 7.06 μm였으며 사분위수 범위5.84-9.23 μm였다. 결막의 미세혈관 직경과 혈류 속도는 통계학적으로 유의한 상관관계를 보이지 않았고(Spearman correlation analysis, p=0.177), 피험자의 나이와 결막미세혈관 혈류 속도 또한 통계학적으로 유의한 상관관계를 보이지 않았다(Spearman correlation analysis test, p=0.669).
결론: 줌렌즈, 초고속 카메라를 장착한 세극등현미경을 이용하여 구결막미세혈관 내 혈류 속도를 영상 분석을 이용하여 쉽고 직관적으로 측정할 수 있었다. 이러한 방법은 미세혈관과 관련된 기초의학, 임상의학 연구에 활용될 수 있을 것으로 기대된다.

다국어 초록 (Multilingual Abstract)

Purpose: To introduce an intuitive method for measuring conjunctival microvascular blood flow velocity by imaging bulbar conjunctival microvessels using a slit-lamp biomicroscope equipped with a zoom lens and an ultra-high-speed camera.
Methods: After obtaining consent from 10 patients (1 male, 9 females) who visited Yeouido St. Mary’s Hospital from August 21, 2020, to June 12, 2021, the patients were examined under a slit lamp microscope equipped with an ultra-high-speed camera and zoom lens. The blood flow in the conjunctival microvessels was photographed. The captured images were analyzed with ImageJ software to measure the blood flow velocity in the conjunctival microvessels, and we investigated whether the blood flow velocity correlated with the vessel diameter and age.
Results: The median age of the subjects was 49.0 years. The mean conjunctival blood flow velocity in 53 microvessels was 0.786 ± 0.468 mm/s. The median conjunctival microvascular diameter was 7.06 μm (interquartile range 5.84 to 9.23 μm). The conjunctival microvascular diameter and blood flow velocity were not significantly correlated (Spearman’s p = 0.177), and the subjects’ age and conjunctival microvascular blood flow velocity were also not correlated (Spearman’s p = 0.669).
Conclusions: In this study, the blood flow velocity in the bulbar conjunctival microvessels could be measured easily by means of image analysis using a slit-lamp microscope equipped with an ultra-high-speed camera with a zoom lens.

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