網膜剥離の超音波診断に関する研究 第1報 網膜裂孔の検出

Ultrasonography in retinal detachment. Part 1. Detection of retinal tear

　硝子体出血などの眼底透見不能時に，網膜裂孔の存在の有無を知ることは，治療方針決定の際に重要である．そこで網膜裂孔の超音波所見を得るために，検眼鏡的に網膜裂孔を認め，かつ網膜剥離を生じていない34眼に超音波検査を施行した．馬蹄形裂孔22眼全例で，B-scanにてflapが一端で眼球壁と連続する短い膜様エコーとして認められ，もう一方の先端と後部硝子体膜との癒着も確認できた．Flapの反射率は全例100％を示し，△dBは15眼において15.1±5.1 dBだった．蓋付裂孔12眼全例で，B-scanにてoper-culumが後部硝子体膜上に存在する比較的高い反射率の短い膜様エコーとして認められた．Oper-culumの反射率は40％から100％で，△dBは6眼において31.2±2.7dBだった．これらの特徴的な所見から，眼底透見不能時においても網膜裂孔，特に馬蹄形裂孔の診断に超音波検査が有用であると結論した．

A consecutive series of 34 eyes, 29 patients, were evaluted by B-scan ultrasonography. All the eyes manifested retinal teras with clear media. The series included 22 eyes with horseshoe tear and 12 eyes with operculated tear, or operculum detached from the tear margin.

In all the eyes with horseshoe tear, the flap was identified as a single short membrane with high re-flectivity (100%). Echographically, the membrane was attached to the eyeglobe at one end and to the posterior vitreous face at the other. The mean standardized reflectivity (△dB) was 15.1 dB with 95% confidence level of 12.5 to 17.7 dB. In 12 eyes with operculated tears, the operculum was identified as a single short membrane, lying along the posterior vitreous face. The reflectivity ranged from 40% to 100%. The findings indicate that ultrasonography, par-ticulary B-scan technique, is a highly reliable means to detect and characterize the retinal tears even in eyes with opaque media.

Rinsho Ganka (Jpn J Clin Ophthalmol) 41(2) : 165-169, 1987