Establishment of a new classification and diagnostic method for hyperalgesic dry eye using functional MRI.

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K18370
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56060:Ophthalmology-related
• Research Institution: Hokkaido University
• Principal Investigator: Tagawa Yoshiaki 北海道大学, 大学病院, 特任助教 (50632494)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ドライアイ / 慢性眼痛 / 痛覚過敏

Outline of Final Research Achievements

In this study, we investigated the central nervous system network of patients with chronic eye pain, who have disproportionately strong subjective symptoms in comparison with other eye pain patients, using functional MRI to compare the central network with that of normal subjects. The results were compared with those of healthy subjects. The results showed that the bilateral dorsal anterior and posterior cingulate gyrus connections were significantly weakened in patients with chronic eye pain compared to healthy subjects. Since the anterior cingulate gyrus, the pain suppression center, is thought to be active in coordination with the posterior cingulate gyrus, the hub of the default mode network, at rest and plays a role in suppressing spontaneous pain, the results suggest that dysfunction of this network causes chronic eye pain.

Free Research Field

ドライアイ

Academic Significance and Societal Importance of the Research Achievements

エアコンのつく快適な室内環境でコンタクトレンズをしてパソコンやスマホで業務をこなす、そんな便利な現代人の生活は眼にとっては過酷な環境で、ドライアイ患者が急増しています。乾燥感や異物感、痛みや頭痛までもが生じますが、なかには眼の痛みが慢性的に持続する慢性眼痛に至ってしまう方もいます。慢性眼痛患者さんは眼の神経が過敏になって、眼の「痛がり屋さん」になっています。この研究では、脳の血流を測定できるMRIという機械を用いて、眼の痛みが末梢にあたる眼の神経だけではなく、脳つまり中枢神経も変化させてしまうことで、持続してしまうことを発見しました。この成果は今後慢性眼痛の治療に役立つかもしれません。